Display device and electronic apparatus using the device

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a display device, and more specifically, to a display device using a liquid crystal as a means for changing the transmission optical axis. In particular, the present invention relates to a so-called semi-transmissive liquid crystal display device that functions as a transmissive liquid crystal display device when the light source is turned on and as a reflective liquid crystal display device when the light source is turned off. Further, the present invention relates to an electronic device such as a clock, an electronic organizer or a personal computer provided with this display device as a display unit.

【0002】

[Conventional technology]

As shown in FIG. 26, a liquid crystal display device using a transmission polarization axis variable optical element 2605 having a variable polarization axis such as a conventional TN (Twisted Nematic) liquid crystal or STN (Super-Twisted Nematic) liquid crystal has a variable transmission polarization axis. Since the structure in which the optical element 2605 was sandwiched between two polarizing plates 2601 and 2606 was adopted, the light utilization efficiency was poor, and especially when the reflective type was used, the display became dark, which was a problem.

【0003】

[Problems to be Solved by the Invention]

Therefore, an object of the present invention is to provide a display device that can obtain a bright display in a display device that uses a transmission polarization axis variable optical element.

【0004】

Further, in the conventional semi-transmissive reflective liquid crystal display device, since the Al reflector is thinly formed or an opening is provided, the reflectance at the time of reflection display is lowered. In other words, by making it a semi-transparent type, the brightness at the time of reflection display was sacrificed.

【0005】

Therefore, another object of the present invention is a semi-transmissive type in which a light source is provided on the back surface side of the reflective liquid crystal display device, and not only the reflection display by external light but also the display by the transmitted light from the light source on the back surface side can be performed. The purpose is to provide a bright reflective liquid crystal element.

【0006】

Further, in the semi-transmissive reflection type liquid crystal display device, the display may be difficult to see if external light is incident on the display device when the light source is lit due to so-called positive / negative inversion.

【0007】

Therefore, an object of the present invention is to provide a display device that does not obscure the display even if positive / negative inversion occurs.

【0008】

[Means for solving problems]

The present invention relates to a transmission polarization axis variable means having a variable transmission polarization axis and a transmission polarization axis variable means having a variable transmission polarization axis in a display device that performs a reflection type display using external light and a transmission type display using light from a light source. Between the polarizing means and the polarization separating means arranged so as to sandwich the polarization means, the light source arranged on the side opposite to the transmission polarization axis variable means with respect to the polarization separating means, and the light source and the polarization separating means. The polarization means is a polarization separation means for emitting light of a predetermined linear polarization component among the incident external light and the light from the light source, and the polarization means. The separating means is a polarized light separating means that transmits and reflects the external light and the light from the light source according to its linear polarization component.

【0009】

In the display device of the present invention, in the case of the reflection type display, the first is a bright display state in which the outside light is reflected by the polarization separating means according to the state of the transmission polarization axis of the transmission polarization axis variable means. A second display state can be obtained in the display state of the above, or in a dark display state in which external light is transmitted through the polarization separating means.

【0010】

Further, in the case of the transmission type display, depending on the state of the transmission polarization axis of the transmission polarization axis variable means, a third display state in which the light from the light source is transmitted through the polarization separation means, or the polarization means is displayed. A fourth display state, which is a dark display in which the light from the light source does not pass through, can be obtained.

【0011】

By the way, when external light is incident in the presence of light from a light source, the above-mentioned bright first display state and dark fourth display state are obtained at the same time, and further, a dark second display state and a bright third display state are obtained. The display state can be obtained at the same time.

【0012】

Therefore, if the light from the light source is white light, the display becomes gray regardless of whether the state of the transmission polarization axis of the transmission polarization axis variable means is on or off, and the display becomes very difficult to see.

【0013】

In the present invention, in order to solve this problem, a colored layer is arranged between the light source and the polarization separating means.

【0014】

Here, the colored layer is a layer capable of transmitting or reflecting light in a predetermined wavelength range and absorbing light having a wavelength other than the predetermined wavelength range.

【0015】

With such a configuration, the light from the light source is colored by passing through the colored layer, so that the above-mentioned third display state becomes a colored color, and thus the above-mentioned third state is colored. Since the color is changed, even if the outside light is incident when the light from the light source is present, the color is displayed on a gray background and the display becomes easy to see.

【0016】

Since the light from the light source is colored by the colored layer, a white light source such as a cold cathode tube may be used as the light source, or an LED or an EL element may be used.

【0017】

Further, in the display device of the present invention, it is preferable to arrange a semi-transmissive reflector between the colored layer and the light source.

【0018】

Here, the semi-transmissive reflector is capable of transmitting light from a light source to the colored layer side, incident on the colored layer from the polarization separating means side, reflecting the light transmitted through the colored layer, and emitting light to the colored layer side. Point to the board.

【0019】

By doing so, the external light once transmitted through the colored layer is reflected by the semitransparent reflector and is transmitted through the colored layer again, so that the degree of coloring in the second display state is increased.

【0020】

As a specific example of the semi-transmissive reflector, a specular reflector provided with an opening can be used.

【0021】

Further, in the present invention, the polarization separating means transmits and reflects light in a substantially entire wavelength range in the visible wavelength region according to its linearly polarized light component.

【0022】

By doing so, a first display state can be obtained for light in the entire visible wavelength range, so that a bright display device can be obtained.

【0023】

Further, according to the display device of the present invention, it is preferable that the polarizing means adopts a polarizing plate that transmits and absorbs incident light according to its linearly polarized light component.

【0024】

Further, according to the display device of the present invention, the polarization separating means is a multilayer film in which a plurality of layers are laminated, and the refractive indexes of the plurality of layers are substantially equal to each other in a predetermined direction between adjacent layers. A different polarization separating means can be used in the direction orthogonal to the predetermined direction.

【0025】

Alternatively, the polarization separating means may have a structure in which a cholesteric layer and a (1/4) λ plate are laminated.

【0026】

A liquid crystal panel can be used as the transmission polarization axis variable means used in the display device of the present invention, and more specifically, a TN liquid crystal panel, an STN liquid crystal panel, an FS TN liquid crystal panel, or an ECB liquid crystal panel is used. be able to.

【0027】

Further, the display device of the present invention is arranged so as to sandwich the liquid crystal panel and the liquid crystal panel in a display device that performs a reflection type display using external light and a transmissive type display using light from a light source. A polarizing plate and a polarizing separator, a light source arranged on the side opposite to the liquid crystal panel with respect to the polarizing separator, and a colored layer arranged between the light source and the polarizing separator are provided. Therefore, the polarizing separator is characterized in that it is a polarizing separator that transmits and reflects the external light and the light from the light source according to its linearly polarized light component.

【0028】

As the liquid crystal panel, it is preferable to use a liquid crystal panel selected from a TN liquid crystal panel, an STN liquid crystal panel, and an ECB liquid crystal panel.

【0029】

Further, the electronic device of the present invention is characterized in that any of the above-mentioned display devices is provided as a display unit.

【0030】

【0031】

【0032】

【0033】

【0034】

【0035】

【0036】

【0037】

【0038】

【0039】

【0040】

【0041】

【0042】

BEST MODE FOR CARRYING OUT THE INVENTION

Next, reference examples and embodiments of the present invention will be described with reference to the drawings.

【0043】

(1st reference example) <Basic structure> FIG. 1 is a cross-sectional view of the display device in the first reference example of the present invention, and FIG. 2 is a schematic cross-sectional view for explaining the display principle of the display device in the first reference example of the present invention.

【0044】

This display device 100 can perform a reflection type display using the reflection of the external light in a place where there is external light, and also performs a transmissive type display by light from a light source even in a place where there is no external light. It is a reflective display device having a so-called transflective function.

【0045】

First, the structure of the display device of this reference example will be described with reference to FIG. In this display device 100, a TN liquid crystal panel 10 is used as a transmission polarization axis variable optical element. In the TN liquid crystal panel 10, the TN liquid crystal 13 is supported between the two glass plates 11 and 12, and a plurality of character display units (not shown) are provided so that the characters can be displayed. A polarizing plate 14 is provided on the upper side of the TN liquid crystal panel 10. A light scatterer 15, a polarizing separator 16, and a light source 17 are provided in this order on the lower side of the TN liquid crystal panel 10. Further, a TAB board (not shown) on which a driver IC for driving the TN liquid crystal 10 is mounted is connected to the TN liquid crystal panel 10 to form a display device.

【0046】

<Polarizing separator> Next, the polarizing separator used in this reference example will be described with reference to FIGS. 3 and 4. FIG. 3 is a schematic configuration diagram of the polarizing separator 16 used in this embodiment, and FIG. 4 is a diagram illustrating the operation of the polarizing separator 16 shown in FIG. The polarization separator 16 has a structure in which two different layers 41 (A layer) and 42 (B layer) are alternately laminated in a plurality of layers. In this polarizing separator 16, the refractive index (nAX) of the A layer 41 in the X-axis direction and the refractive index of the B layer 42 in the X-axis direction (n BX) are different, but the refraction of the A layer 41 in the Y-axis direction. The rate (nAY) and the refractive index (nBY) of layer B 42 in the Y-axis direction are substantially equal. Of the light incident on the polarizing separator 16, linearly polarized light in the Y-axis direction is transmitted through the polarizing separator 16 because the refractive indexes of the A layer 41 and the B layer 42 of the polarizing separator 16 are substantially the same. To do. On the other hand, assuming that the thickness of the polarizing separator 16 in the A layer 41 in the Z-axis direction is tA and the thickness of the B layer 41 is tB. tA nAX + tB nBX = λ / 2 (1) Of the light having a wavelength of λ and incident on the polarizing separator 16, the linearly polarized light in the X-axis direction is reflected by the polarizing separator 16. Since the thickness of the A layer 41 in the Z-axis direction and the thickness of the B layer 42 in the Z-axis direction are variously changed, the polarizing separator 16 is incident on the polarizing separator 16 over a wide range of the visible wavelength region. Of the light, it reflects linearly polarized light in the X-axis direction.

【0047】

For example, a stretched polyethylene naphthalate (PEN) is used for the A layer 41 of the polarization separator 16, and a copolyester (coPEN) of naphthalene dicarponic acid and terephthalic acid is used for the B layer 42. ; Copolyester of napthalene dicarboxylic acid and terephthallic or isothalic acid) can be used.

【0048】

Of course, the material of the polarizing separator 16 used in the present invention is not limited to this, and the material can be appropriately selected. The details of such a polarizing separator are disclosed as a reflective pollizer in an internationally published international application (international application numbers: WO95 / 27819 and WO95 / 17692).

【0049】

In this reference example, the above-mentioned polarizing separator is used, but in addition to this polarizing separator, for example, a cholesteric liquid crystal layer sandwiched between λ / 4 plates and a Brewster angle (SID 92 DIGEST). (Pages 427 to 429), those using holograms, etc. have the same functions as the above-mentioned polarizing separator, and they may be used in the display device of this reference example.

【0050】

<Display Principle> Next, the principle of display by the display device 100 will be described with reference to FIG. 2 with the right half of the display device 100 as the voltage application section and the left half as the voltage non-application section. First, a reflective display when external light is incident on the display device 100 will be described.

【0051】

In the voltage-free portion on the left side, when external light enters the display device 100, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then the polarization direction is twisted by 90 ° by the TN liquid crystal 13. It becomes linearly polarized light in the direction perpendicular to the paper surface, is reflected by the polarizing separator 16 as linearly polarized light in the direction perpendicular to the paper surface, and the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to be a straight line in the direction parallel to the paper surface. It becomes polarized light and is emitted from the polarizing plate 14 as linearly polarized light in a direction parallel to the paper surface. As described above, when no voltage is applied, the incident external light is reflected instead of being absorbed by the polarizing separator 16, so that a bright reflection type display can be obtained. Since the light scatterer 15 is provided between the polarizing separator 16 and the TN liquid crystal panel 10, the reflected light from the polarizing separator 16 changes from a mirror surface to a white shape.

【0052】

In the Denjo application section on the right side, when external light enters the display device 100, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then the TN liquid crystal 13 is polarized without changing the polarization direction. It transmits, and the polarizing separator 16 also transmits without changing the polarization direction and reaches the light source 17. Most of the light that reaches the light source 17 is transmitted through the light source or absorbed by the light source, resulting in a dark display.

【0053】

As described above, regarding the reflection type display when the external light is incident on the display device 100, the light reflected by the polarizing separator 16 is transmitted through the light scattering body 15 and becomes a bright display in the voltage-free portion. In the voltage application section, most of the light transmitted through the polarizing separator 16 is transmitted through the light source 17 or is absorbed by the light source 17, resulting in a dark display.

【0054】

Then, in the voltage-free portion, the external light incident on the display device 100 is reflected without being absorbed by the polarizing separator 16, so that a bright display can be obtained.

【0055】

Next, a transmission type display by light from the light source 17 will be described.

【0056】

In the no-voltage section on the left side, the light from the light source 17 enters the polarizing separator 16, and the polarizing separator 16 makes linearly polarized light in the direction parallel to the paper surface, and then the TN liquid crystal 13 twists the polarization direction by 90 °. It becomes linearly polarized light in the direction perpendicular to the paper surface, and is absorbed by the polarizing plate 14 to produce a dark display.

【0057】

In the voltage application section on the right side, the light from the light source 17 is incident on the polarizing separator 16, linearly polarized light in the direction parallel to the paper surface by the polarizing separator 16, scattered light by the light scatterer 15, and then the TN liquid crystal 13 Is transmitted without changing the polarization direction, and the polarizing plate 14 is also transmitted to obtain a bright display.

【0058】

As described above, regarding the transmission type display by the light from the light source 17, the light from the light source 17 is absorbed by the polarizing plate 14 in the voltage-unapplied portion and becomes a dark display, and the polarizing plate 14 is displayed in the voltage-applied portion. The display is transparent and bright.

【0059】

Therefore, the display device 100 can display a bright reflection type by utilizing the reflection of the external light in a place where there is external light, and is a transmissive type by the light from the light source 17 even in a place where there is no external light. It is a reflection type display device having a so-called transflective type function capable of displaying.

【0060】

<Scattering plate> As the scattering plate used for the display device in this reference example, a scattering plate capable of emitting the incident light without eliminating the polarization state as much as possible is used. Since this scattering plate has a function of scattering and clouding the light emitted from the scattering plate, a display device having a cloudy display (white display) can be obtained. On the other hand, when the scattering plate 15 is removed from the configuration, the display device can obtain a glossy color display. Therefore, it is advisable to dispose of the scattering plate according to the application of the display device.

【0061】

<Light source> 6 to 9 show the display device of this reference example when various light sources are used. In this reference example, any of the light sources shown in FIGS. 6 to 9 can be used. The liquid crystal device using the light source shown in FIG. 5 is a display device of a comparative example.

【0062】

Light source is used in the display device shown in FIG. 5, not include the cold cathode tubes 50 and the light guide plate 51 is a light source that. A light guide plate 51 having a light absorption function is used when the cold cathode tube 50 is turned off.

【0063】

When the light source shown in FIG. 5 is used for the display device of this reference example, the display when external light containing visible wavelength components of multiple colors is incident, that is, the reflection type display is displayed in black at the voltage application part, and the voltage is displayed. White is displayed in the non-applied part. On the other hand, regarding the transmission type display by the light from the light source, the output light color of the cold cathode tube is displayed in white in the voltage application section, and black is displayed in the voltage non-application section.

【0064】

The light source used in the display device shown in FIG. 6 employs an LED 60 that emits light having a red wavelength as a light source, and further includes a light guide sheet 61. When the light source shown in FIG. 6 is used in the display device of the present embodiment, the reflection type display is displayed in black in the voltage application section and white in the voltage non-application section. On the other hand, regarding the transmission type display by the light from the light source, the output light color from the LE D60 is displayed in the voltage application section, that is, the red display is displayed, and the black display is displayed in the voltage non-application section.

【0065】

By the way, when the light source shown in FIG. 5 is used, as described above, for the light from the light source 17, a dark display is obtained in the voltage non-applied portion and a bright display is obtained in the voltage applied portion. However, when external light is incident from the front side of the display device, the external light causes a bright display in the voltage-unapplied group and a dark display in the voltage-applied part. It becomes. As a result, in both the voltage non-applied part and the voltage applied part, for example, when the display by the transmitted light from the light source 17 is bright, the dark display of the reflection type by the external light is added and the display becomes gray, and the light source becomes a light source. Even if the display due to the transmitted light from 17 is dark, a bright display that is reflected by external light is added, and the display is also gray, which causes a so-called positive / negative inversion phenomenon, which may make the display difficult to see. is there.

【0066】

When the light source shown in FIG. 6 is turned on when the external light is incident, the light emitted from the LE D can be seen in the voltage application part, so that the display becomes grayish red, and in the voltage non-application part, the polarizing separator 16 is used. Since the reflected external light can be seen, the display is gray, which makes it much easier to see than a simple black-and-white display.

【0067】

In FIG. 6, the LED 60 that emits light having a red wavelength is used, but of course, an LED that emits light having a wavelength other than red may be used.

【0068】

The light source used in the display device shown in FIG. 7 employs an EL element 70 that emits light having a green wavelength as a light source. When the light source shown in FIG. 7 is used in the display device of the present embodiment, the reflection type display is displayed in black in the voltage application section and white in the voltage non-application section. On the other hand, regarding the transmission type display by the light from the light source, the output light color from the EL element 70 is displayed in the voltage application section, that is, the green display is displayed, and the black display is displayed in the voltage non-application section. When the light source shown in FIG. 7 is turned on when the external light is incident, the light emitted from the EL element 70 can be seen in the voltage application part, so that the display becomes grayish green, and in the voltage non-application part, the polarizing separator Since the outside light reflected by is visible, it is displayed in gray. In FIG. 7, the EL element 70 that emits light having a linear color wavelength is used, but of course, an EL element that emits light having a wavelength other than green may be used.

【0069】

As the light source used in the display device shown in FIG. 8, a LE D81 that emits light having a red wavelength and a LE D82 that emits light having a blue wavelength are arranged on the side surface of the light guide plate 83 as light sources. The light guide plate is partitioned by a reflector 84 for each area corresponding to each LED so that the light of each wavelength emitted from the light guide plate is not mixed. Further, each LE D is arranged so that its emitted light corresponds to a plurality of character display units 85 and 86 formed on the liquid crystal panel. When the light source shown in FIG. 8 is used in the display device of the present embodiment, the reflection type display is displayed in black in the voltage application section and white in the voltage non-application section. On the other hand, regarding the transmission type display by the light from the light source, in the voltage application part, each character display part displays the emission light color from each corresponding LED, that is, red or blue display, and in the voltage non-application part, it displays black. Become. When the light source shown in FIG. 8 is used to turn on the light source when external light is incident, each LE is applied to the voltage application unit. Since the light emitted from D can be seen, each character display unit has a grayish red or blue display, and in the no-voltage portion, the external light reflected by the polarizing separator can be seen, so that the display is gray. In FIG. 8, an LED that emits light having a red wavelength and an LED that emits light having a blue wavelength are used, but of course, an LED that emits light having a wavelength other than these colors may be used, and a combination thereof is also used. Can be selected as appropriate.

【0070】

As the light source used in the display device shown in FIG. 9, a plurality of LEDs 91 that emit light having a red wavelength and a plurality of LEDs 92 that emit light having a blue wavelength are arranged as an aggregate for each color. There is. The light source in FIG. 9 is not provided with a light guide plate. Further, each LED group is arranged so that the emitted light corresponds to a plurality of character display units 93 and 94 formed on the liquid crystal panel. When the light source shown in FIG. 9 is used in the display device of the present embodiment, the reflection type display is displayed in black in the voltage application section and white in the voltage non-application section. On the other hand, regarding the transmission type display by the light from the light source, in the voltage application part, each character display part displays the emission light color from each LED group corresponding to each, that is, red or blue display, and in the voltage non-application part, black. It becomes a display. When the light source shown in FIG. 9 is used to turn on the light source when external light is incident, each LE is applied to the voltage application unit. Since the emitted light from the D group can be seen, each character display unit has a grayish red or blue display, and in the no-voltage portion, the external light reflected by the polarizing separator can be seen, so that the display is gray. In FIG. 9, an LED 91 that emits light having a red wavelength and an LED 92 that emits light having a blue wavelength are used, but of course, an LED that emits light having a wavelength other than these colors may be used, and the combination thereof is also appropriate. You can choose.

【0071】

(Second reference example) FIG. 10 is a cross-sectional view of the display device according to the second embodiment of the present invention, and FIG. 11 is a schematic cross-sectional view for explaining the display principle of the display device of the second reference example of the present invention.

【0072】

This display device 1000 can perform a reflection type display utilizing the reflection of the external light in a place where there is external light, and also performs a transmissive type display by light from a light source even in a place where there is no external light. It is a reflective display device having a so-called transflective function.

【0073】

<Basic structure> First, the structure of the display device of this reference example will be described with reference to FIG. In this display device 1000, a TN liquid crystal panel 10 is used as a transmission polarization axis variable optical element. In the TN liquid crystal panel 10, the TN liquid crystal 13 is sandwiched between two glass plates 11 and 12, and a plurality of character display units (not shown) are provided so that characters can be displayed. A polarizing plate 14 is provided on the upper side of the TN liquid crystal panel 10. A light scatterer 15, a polarizing separator 101, a light absorber 102, and a light source 17 are provided in this order on the lower side of the TN liquid crystal panel 10. The light absorber 102 is black, and a plurality of openings 103 are provided with a predetermined area density. Further, a TAB board (not shown) on which a driver IC for driving the TN liquid crystal 13 is mounted is connected to the TN liquid crystal panel 10 to form a display device.

【0074】

<Polarizing Separator> The polarizing separator 101 includes a (1/4) λ plate 104 and a cholesteric liquid crystal layer 105. The cholesteric liquid crystal 105 has a property of light having the same wavelength as the pitch of the liquid crystal, reflecting circularly polarized light in the same rotation direction as the liquid crystal, and transmitting other light. Therefore, for example, when a cholesteric liquid crystal having a pitch of 5000 angstroms and rotating counterclockwise is used for the cholesteric liquid crystal layer 105, the left circularly polarized light having a wavelength of 5000 angstroms is reflected, and the right circularly polarized light and the left circularly polarized light of other wavelengths are transmitted. Is obtained. Furthermore, by using a counterclockwise rotating cholesteric liquid crystal and changing its pitch within the cholesteric liquid crystal over the entire wavelength range of visible light, left circularly polarized light is reflected not only in a single color but also in all bright colored light, and right circularly polarized light is transmitted. The element to be used is obtained. In the present embodiment, as the cholesteric liquid crystal layer 105, a counterclockwise cholesteric liquid crystal is used, and the pitch thereof is changed in the cholesteric liquid crystal over the entire wavelength range of visible light.

【0075】

In the polarizing separator 101 in which the cholesteric liquid crystal layer 105 and the (1/4) λ plate 104 are combined, when linearly polarized light in a predetermined first direction is incident from the side of the (1/4) λ plate 104. It becomes left circularly polarized light by the (1/4) λ plate 104, is reflected by the cholesteric liquid crystal layer 105, and is emitted again as linearly polarized light in a predetermined first direction by the (1/4) λ plate 104. Further, when linearly polarized light in the second direction orthogonal to the first direction is incident, it becomes right-handed circularly polarized light by the (1/4) λ plate 104 and passes through the cholesteric liquid crystal layer 105. Further, with respect to the light incident from the lower side of the cholesteric liquid crystal layer 105, linearly polarized light in the second direction is emitted above the (1/4) λ plate 104.

【0076】

In this way, the polarizing separator 101 in which the cholesteric liquid crystal layer 105 and the (1/4) λ plate 104 are combined is a straight line in a predetermined second direction of the light incident from the (1/4) λ plate 104 side. The polarization component is transmitted, the linear polarization component in the first direction orthogonal to the predetermined second direction is reflected, and the light incident from the cholesteric liquid crystal layer 105 side is (1/4) on the λ plate 104 side. It is a polarization separating means capable of emitting linearly polarized light in the second direction. As a polarizing separator having this function, in addition to the polarizing separator 101 in which the cholesteric liquid crystal layer 105 and the (1/4) λ plate 104 are combined, a film in which a multilayer film is laminated is used (USP 4,974,219). ), Those that separate reflected polarized light and transmitted polarized light using the angle of the viewer (SID 92DIGEST pages 427 to 429), those that use holograms, and those described above using FIGS. 3 and 4. Some of the polarizing separators described in the first reference example are disclosed in internationally published international applications (international application numbers: WO95 / 27819 and WO95 / 17692).

【0077】

<Display Principle> Next, the display by the display device 1000 will be described with the right half of the display device 1000 as the voltage application section and the left half as the voltage non-application section.

【0078】

First, a reflective display when external light is incident on the display device 1000 will be described.

【0079】

In the voltage-free portion on the left side, when external light enters the display device 1000, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then the polarization direction is twisted by 90 ° by the TN liquid crystal 13. It becomes linearly polarized light in the direction perpendicular to the paper surface, becomes left circularly polarized light by the (1/4) λ plate 104, is reflected by the cholesteric liquid crystal layer 105, and is reflected on the (1/4) λ plate 104 again, and (1/4) 4) The λ plate 104 produces linearly polarized light in the direction perpendicular to the paper surface, and the TN liquid crystal 13 twists the polarization direction by 90 ° to produce linearly polarized light in the direction parallel to the paper surface. It emits as. As described above, in the voltage-free portion, the incident external light is reflected rather than absorbed by the polarizing separator 101, so that a bright reflection type display can be obtained. Since the light scatterer 15 is provided between the (1/4) λ plate 104 and the TN liquid crystal panel 10, the reflected light from the polarizing separator 101 changes from a mirror surface to a bright color.

【0080】

In the voltage application section on the right side, when external light enters the display device 1000, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then transmitted through the TN liquid crystal 13 without changing the polarization direction. Then, it becomes right-handed circularly polarized light by the (1/4) λ plate 104 and passes through the cholesteric liquid crystal layer 105. The right circularly polarized light transmitted through the cholesteric liquid crystal layer 105 is absorbed by the black light absorber 102, resulting in a dark display.

【0081】

As described above, regarding the reflection type display when the external light is incident on the liquid crystal display device 1000, the light reflected by the polarizing separator 101 is transmitted through the light scatterer 15 and becomes a bright display in the voltage-free portion. In the voltage application section, the light transmitted through the polarizing separator 101 is absorbed by the black light absorber 102, resulting in a dark display.

【0082】

Then, in the voltage-free portion, the external light incident on the display device 1000 is reflected without being absorbed by the polarizing separator 101, so that a bright display can be obtained.

【0083】

Next, a transmission type display by light from the light source 17 will be described.

【0084】

In the no-voltage portion on the left side, the light from the light source 17 is incident on the cholesteric liquid crystal layer 105 of the polarizing separator 101 through the opening 103 provided in the black light absorber 102, and the cholesteric liquid crystal layer 105 is on the right side. Only circularly polarized light is transmitted, and the (1/4) λ plate 104 produces linearly polarized light in the direction parallel to the paper surface, and then the TN liquid crystal 13 twists the polarization direction by 90 ° to produce linearly polarized light in the direction perpendicular to the paper surface. , It is absorbed by the polarizing plate 14 and the display becomes dark.

【0085】

In the voltage application section on the right side, the light from the light source 17 is incident on the polarizing separator 101 and the cholesteric liquid crystal layer 105 through the opening 103 provided in the black light absorber 102, and the cholesteric liquid crystal layer 105 is formed in the right circle. Only polarized light is transmitted, and the (1/4) λ plate 104 becomes linearly polarized light in the direction parallel to the paper surface, passes through the light scatterer 15, and then transmits the TN liquid crystal 13 without changing the polarization direction, and is polarized. The board 14 is also transparent and becomes a bright display.

【0086】

As described above, regarding the transmission type display by the light from the light source 17, the light from the light source 17 is absorbed by the polarizing sheet 14 in the voltage-unapplied portion and becomes a dark display, and the polarization slope 14 is displayed in the voltage-applied portion. The display is transparent and bright.

【0087】

Therefore, the display device 1000 can display a bright reflection type by utilizing the reflection of the external light in a place where there is external light, and is a transmissive type by the light from the light source 17 even in a place where there is no external light. It is a reflection type display device having a so-called transflective type function capable of displaying.

【0088】

<Scattering plate> As the scattering plate 15 used in the display device in this reference example, a scattering plate capable of emitting light without eliminating the polarization state of the incident light is used. Since the scattering plate 15 has a function of scattering and clouding the light emitted from the scattering plate, a display device having a cloudy display (white display) can be obtained. On the other hand, when the scattering plate 15 is removed from the configuration, the display device can obtain a glossy color display. Therefore, it is advisable to dispose of the scattering plate according to the application of the display device.

【0089】

<Light absorber> In this reference example, in the reflection type display when external light is incident on the display device 1000, as described above, the bright display by the light reflected from the polarizing separator 101 and the light transmitted through the polarizing separator 101 are transmitted. Two display states are obtained: a dark display in which light is absorbed by the light absorber 102. However, the light absorber 102 is a black light absorber that absorbs light from the polarization separator 101 and has a plurality of openings 103 so that light can be transmitted through the openings 103. Therefore, in the dark display state, not all the light is absorbed by the light absorber 103, but a certain amount of light is transmitted through the light absorber 102 through the opening 103, and the light source 17 and the like. It is reflected by the light absorber 102, passes through the light absorber 102 through the opening 103, and returns to the TN liquid crystal panel 10 side, which lowers the contrast.

【0090】

Therefore, preferably, by limiting the ratio of the opening 103 to the light absorber 102, light is transmitted through the opening 103, reflected by the light source 17 or the like, and absorbed again. The amount of light returned through the opening 103 of the body 102 can be reduced, and the decrease in contrast can be suppressed.

【0091】

In this reference example, as the light absorber 102, a black light absorber having a plurality of openings 103 is used, but a gray transflective light absorber can also be used, which is also a polarization separator. The light from the 101 side can be absorbed and the light from the light source 17 can be transmitted to the polarizing separator 101 side. Since the light absorber in this case is in a gray semi-transmissive state, it is not necessary to provide an opening. As the gray transflective light absorber, a light diffusing film D202 (Tsujimoto Electric Mfg. Co., Ltd.) or the like can be used.

【0092】

Alternatively, as the light absorber 102, a black light absorber having a plurality of openings 103 is used, but instead of the light absorber 102, a polarizing plate whose absorption axis is deviated from that of the polarizing separator 101 is used. You can also. In this way, the polarizing separator 101 and the polarizing plate with the absorption axis shifted can absorb the light from the TN liquid crystal panel 10 side and transmit the light from the light source 17 to the TN liquid crystal panel 10 side. ..

【0093】

<Light source> As the display device in this reference example, various light sources shown in FIGS. 6 to 9 and described in the first reference example can be used. Since the action and effect are the same as those of the first reference example, the description thereof is omitted here.

【0094】

(Third reference example) <Basic structure> FIG. 12 is a schematic cross-sectional view for explaining a display device of a third reference example of the present invention.

【0095】

In the second reference example described above, the polarizing separator 101 including the (1/4) λ plate 104 and the cholesteric liquid crystal layer 105 was used, but in this reference example, the polarizing separator 101 is replaced with the polarizing separator 101. It differs from the second reference example in that a polarizing separator 121 having a (1/4) λ plate 104, a cholesteric liquid crystal layer 105, and a (1/4) λ plate 120 is used, but the other points are the same.

【0096】

<Polarizing Separator> In such a polarizing separator 121 in which (104) λ plates 104 and 120 are provided on both sides of the cholesteric liquid crystal layer 105, a predetermined first direction is performed from the side of the (1/4) λ slope 104. When the linearly polarized light of (1/4) is incident, it becomes left circularly polarized light by the (1/4) λ plate 104, is reflected by the cholesteric liquid crystal layer 105, and becomes linearly polarized light in the predetermined first direction again by the (1/4) λ plate 104. Exit. In addition, when linearly polarized light in the second direction orthogonal to the first direction is incident, it becomes right-handed circularly polarized light by the (1/4) λ plate 104, passes through the cholesteric liquid crystal layer 105, and passes through the (1/4) λ plate 120. Is emitted again as linearly polarized light in the second direction. Further, for the light incident from the lower side of the (1/4) λ plate 146, linearly polarized light in the second direction is emitted above the (1/4) λ plate 104.

【0097】

In this way, the polarizing separator 121 in which the cholesteric liquid crystal layer 105 and the (1/4) λ plates 104 and 120 are combined has a predetermined second direction of the light incident from the (1/4) λ plate 104 side. The linearly polarized light component of is transmitted as linearly polarized light in the second direction, the linearly polarized light component in the first direction orthogonal to the predetermined second direction is reflected, and the light incident from the (1/4) λ plate 120 side. On the other hand, it is a polarization separating means capable of emitting linearly polarized light in the second direction on the (1/4) λ plate 104 side. As the polarization separating means having this function, in addition to the polarization separator 121 which is a combination of the cholesteric liquid crystal layer 105 and the (1/4) λ plates 104 and 120, a film in which a multilayer film is laminated is used (USP4). , 974,219), using the angle of the brewer to separate reflected polarized light and transmitted polarized light (SID 92 DIGEST pages 427 to 429), using holograms, and using Fig. 3 and Fig. 4. The polarizing separator described in the first reference example, that is, an internationally published international application (international application numbers: WO95 / 27819 and WO / 17692), is disclosed as a reflective polrizer.

【0098】

<Display Principle> Next, the display by the display device 1200 will be described with the right half of the display device 1200 as the voltage application section and the left half as the voltage non-application section.

【0099】

First, a reflective display when external light is incident on the display device 1200 will be described.

【0100】

The function of the voltage non-applied part on the left side is the same as the function of the voltage non-applied part of the first reference example described above. That is, when the outside light enters the display device 1200, the outside light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to be the direction perpendicular to the paper surface. It becomes linearly polarized light of (1/4) λ sheet 104 and becomes left circularly polarized light, is reflected by the cholesteritter liquid crystal layer 105 and is incident on the (1/4) λ plate 104 again, and is reflected by the (1/4) λ plate 104. It becomes linearly polarized light in the direction perpendicular to the paper surface, and the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to become linearly polarized light in the direction parallel to the paper surface, and is emitted from the polarizing sheet 14 as linearly polarized light in the direction parallel to the paper surface. As described above, in the voltage-free portion, the incident external light is reflected rather than absorbed by the polarizing separator 121, so that a bright reflection type display can be obtained. Since the light scatterer 15 is provided between the (1/4) λ sheet 104 and the TN liquid crystal panel 10, the reflected light from the polarizing separator 121 changes from a mirror surface to a white color.

【0101】

In the voltage application section on the right side, when external light enters the display device 1200, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing sheet 14, and then transmitted through the TN liquid crystal 13 without changing the polarization direction. Then, the (1/4) λ plate 104 makes it right-handed circularly polarized light, which is transmitted through the cholesteric liquid crystal layer 105, and the right-handed circularly polarized light that is transmitted through the cholesteric liquid crystal layer 105 is in the direction parallel to the paper surface by the (1/4) λ plate 120. It becomes linearly polarized light, and then it is absorbed by the black light absorber 102, resulting in a dark display.

【0102】

As described above, regarding the reflection type display when the external light is incident on the display device 1200, the polarization separator 121 is reflected by the polarization separator 121 in the voltage non-applied portion, and the polarization separator 121 is displayed in the voltage application portion. The transmitted light is absorbed by the black light absorber 102, resulting in a dark display.

【0103】

Then, in the voltage-free portion, the external light incident on the display device 1200 is reflected without being absorbed by the polarizing separator 121, so that a bright display can be obtained.

【0104】

Next, a transmission type display by light from the light source 17 will be described.

【0105】

In the no-voltage portion on the left side, the light from the light source 17 is incident on the (1/4) λ plate 120 of the polarizing separator 121 through the opening 103 provided in the black light absorber 102, and (1). / 4) After passing through the λ plate 120, it enters the cholesteric liquid crystal layer 105, and the right circularly polarized light is transmitted and the left circularly polarized light is reflected by the cholesteric liquid crystal layer 105. The transmitted circularly polarized light is linearly polarized in the direction parallel to the paper surface by the (1/4) λ plate 104, and then the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to become linearly polarized light in the direction perpendicular to the paper surface. It is absorbed by 14 and becomes a dark display.

【0106】

In the voltage application section on the right side, the light from the light source 17 enters the (1/4) λ plate 120 of the polarizing separator 121 through the opening 103 provided in the black light absorber 102, and then the cholesteric. Of the light incident on the liquid crystal layer 105, only the right circularly polarized light is transmitted, and the (1/4) λ plate 104 becomes linearly polarized light in the direction parallel to the paper surface, passes through the light scatterer 15, and then transmits the TN liquid crystal 13. It transmits without changing the polarization direction, and also transmits the polarizing plate 14, resulting in a bright display.

【0107】

As described above, regarding the transmission type display by the light from the light source 17, the light from the light source 17 is absorbed by the polarizing sheet 14 in the voltage-unapplied portion and becomes a dark display, and the polarizing plate 14 is displayed in the voltage-applied portion. The display is transparent and bright.

【0108】

Therefore, this display device 1200 can display a bright reflection type by utilizing the reflection of the external light in a place where there is external light, and is a transmissive type by the light from the light source 17 even in a place where there is no external light. It is a reflection type display device having a so-called transflective type function capable of displaying.

【0109】

<Scattering plate> As the scattering plate used for the display device in this reference example, a scattering plate capable of emitting the incident light without eliminating the polarization state as much as possible is used. Since this scattering plate has a function of scattering and clouding the light emitted from the scattering plate, a display device having a cloudy display (white display) can be obtained. On the other hand, when the scattering plate 15 is removed from the configuration, the display device can obtain a glossy color display. Therefore, it is advisable to dispose of the scattering plate according to the application of the display device.

【0110】

<Light absorber> As the light absorber used in this reference example, the same one as that used in the second reference example can be used. As in the second reference example, the decrease in contrast can be suppressed by limiting the ratio of the opening 103 to the light absorber 102. Of course, as in the second reference example, a semi-transmissive light absorber or a polarizing plate whose absorption axis is deviated from that of the polarizing separator 121 can also be used.

【0111】

<Light source> As the display device in this reference example, various light sources described in FIGS. 6 to 9 and the first reference example can be used. Since the action and effect are the same as those of the first reference example, the description thereof is omitted here.

【0112】

(4th reference example) <Basic structure> FIG. 13 is a schematic cross-sectional view for explaining the display device of the fourth reference example of the present invention.

【0113】

In the second reference example described above, the polarizing separator 101 including the (1/4) λ plate 104 and the cholesteric liquid crystal layer 105 is used, and in the third reference example, the (1/4) λ plate 104 A polarizing separator 121 having a cholesteric liquid crystal layer 105 (1/4) λ plate 120 was used, but in the present embodiment, FIGS. 3 and 4 are used instead of these polarizing separators 101 and 121. The polarization separator described in the first reference example, that is, the polarization separator disclosed in the internationally published international application (international application numbers: WO95 / 27819 and WO95 / 17692) is used as the polarization separator 16. The points are different from those of the second and third embodiments, but the other points are the same as those of the second reference example and the third reference example.

【0114】

<Polarizing separator> In this reference example, the same one as described in the first reference example with reference to FIGS. 3 and 4 is used. The detailed description thereof will be omitted here. Of course, in addition to this polarizing separator, for example, a cholesteric liquid crystal layer sandwiched between λ / 4 plates, one that uses the angle of Brewster (SID 92DIGEST pages 427 to 429), one that uses holograms, etc. It has the same functions as the above-mentioned polarization separator, and they may be used in the display device of this reference example.

【0115】

<Display Principle> Next, the display by the display device 11300 will be described with the right half of the display device 1300 as the voltage application section and the left half as the voltage non-application section.

【0116】

First, a reflective display when external light is incident on the display device 1300 will be described.

【0117】

In the voltage-free portion on the left side, when external light enters the display device 1300, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then the polarization direction is twisted by 90 ° by the TN liquid crystal 13. It becomes linearly polarized light in the direction perpendicular to the paper surface, is reflected by the polarizing separator 16 as linearly polarized light in the direction perpendicular to the paper surface, and the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to be a straight line in the direction parallel to the paper surface. It becomes polarized light and is emitted from the polarizing plate 14 as linearly polarized light in a direction parallel to the paper surface. As described above, in the voltage-free portion, the incident external light is reflected instead of being absorbed by the polarizing separator 16, so that a bright reflection type display can be obtained. Since the light scatterer 15 is provided between the polarizing separator 16 and the TN liquid crystal panel 10, the reflected light from the polarizing separator 16 changes from a mirror surface to a bright color.

【0118】

In the voltage application section on the right side, when external light enters the display device 1300, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then transmitted through the TN liquid crystal 13 without changing the polarization direction. However, the polarizing separator 16 also transmits the polarized light without changing the polarization direction, and then is absorbed by the black light absorber 102, resulting in a dark display.

【0119】

As described above, regarding the reflection type display when the external light is incident on the display device 1300, the light reflected by the polarizing separator 16 is transmitted through the light scatterer 15 and becomes a bright display in the voltage-free portion. In the voltage application section, the light transmitted through the polarizing separator 16 is absorbed by the black light absorber 102, resulting in a dark display.

【0120】

When no voltage is applied, the external light incident on the display device 1300 is reflected without being absorbed by the polarizing separator 16, so that a bright display can be obtained.

【0121】

Next, a transmission type display by light from the light source 17 will be described.

【0122】

In the no-voltage portion on the left side, the light from the light source 17 enters the polarizing separator 16 through the opening 103 provided in the black light absorber 102, and the polarizing separator 16 makes a direction parallel to the paper surface. After that, the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to become linearly polarized light in the direction perpendicular to the paper surface, which is absorbed by the polarizing plate 14 to produce a dark display.

【0123】

In the voltage application section on the right side, the light from the light source 17 enters the polarizing separator 16 through the opening 103 provided in the black light absorber 102, and is a straight line in the direction parallel to the paper surface by the polarizing separator 16. It becomes polarized light, becomes scattered light by the light scatterer 15, and then transmits the TN liquid crystal 10 without changing the polarization direction, and also transmits the polarizing plate 14 to obtain a bright display.

【0124】

As described above, regarding the transmission type display by the light from the light source 17, the light from the light source 17 is absorbed by the polarizing plate 14 in the voltage-unapplied portion and becomes a dark display, and the polarizing plate 14 is displayed in the voltage-applied portion. The display is transparent and bright.

【0125】

Therefore, this display device 1300 can display a bright reflection type by utilizing the reflection of the external light in a place where there is external light, and is a transmissive type by the light from the light source 17 even in a place where there is no external light. It is a reflection type display device having a so-called transflective type function capable of displaying.

【0126】

<Scattering plate> As the scattering plate used for the display device in this reference example, a scattering plate capable of emitting the incident light without eliminating the polarization state as much as possible is used. Since this scattering plate has a function of scattering and clouding the light emitted from the scattering plate, a display device having a cloudy display (white display) can be obtained. On the other hand, when the scattering plate 5 is removed from the configuration, it becomes a display device that can obtain a glossy color display. Therefore, it is advisable to dispose of the scattering plate according to the application of the display device.

【0127】

<Light absorber> As the light absorber used in this reference example, the same one as that used in the second reference example can be used. As in the second reference example, the decrease in contrast can be suppressed by limiting the ratio of the opening 103 to the light absorber 102. Of course, as in the second reference example, a semi-transmissive light absorber or a polarizing plate whose absorption axis is deviated from that of the polarizing separators 101 and 121 can also be used.

【0128】

<Light source> As the display device in this reference example, various light sources described in FIGS. 6 to 9 and the first reference example can be used.

【0129】

Since the action and effect are the same as those of the first reference example, the description thereof is omitted here.

【0130】

(Fifth reference example) FIG. 14 is a cross-sectional view of the display device in the fifth reference example of the present invention, and FIG. 15 is a schematic cross-sectional view for explaining the display principle of the display device in the fifth reference example of the present invention.

【0131】

This display device 100 can perform a reflection type display using the reflection of the external light in a place where there is external light, and also performs a transmissive type display by light from a light source even in a place where there is no external light. It is a reflective display device having a so-called transflective function.

【0132】

<Basic structure> First, the structure of the display device of this reference example will be described with reference to FIG. In this display device 1400, a TN liquid crystal panel 10 is used as a transmission polarization axis variable optical element. In the TN liquid crystal panel 10, the TN liquid crystal 13 is sandwiched between the two glass plates 11 and 12, and a plurality of character display units (not shown) are provided so that the characters can be displayed. A shining plate 14 is provided on the upper side of the TN liquid crystal panel 10. A light scatterer 15, a polarizing separator 16, a diffuser 140, and a light source 17 are provided in this order on the lower side of the TN liquid crystal panel 10. The diffuser plate 140 uses a scattering plate capable of changing the polarization state of the incident light and emitting the light. Further, a TAB board (not shown) on which a driver IC for driving the TN liquid crystal 13 is mounted is connected to the TN liquid crystal panel 10 to form a display device.

【0133】

<Polarizing separator> In this reference example, the same one as described in the first reference example with reference to FIGS. 3 and 4 is used. The detailed description thereof will be omitted here. Of course, in addition to this polarizing separator, for example, a cholesteric liquid crystal layer sandwiched between λ / 4 plates, one that uses the angle of Brewster (SID 92DIGEST pages 427 to 429), one that uses holograms, etc. It has the same functions as the above-mentioned polarization separator, and they may be used in the display device of this reference example.

【0134】

<Display Principle> Next, the display by the display device 1400 will be described with reference to FIG. 15, with the right half of the display device 1400 as the voltage application section and the left half as the voltage non-application section.

【0135】

First, a reflective display when external light is incident on the display device 1400 will be described.

【0136】

In the voltage-free portion on the left side, when external light enters the display device 1400, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then the polarization direction is twisted by 90 ° by the TN liquid crystal 13. It becomes linearly polarized light in the direction perpendicular to the paper surface, is reflected by the polarizing separator 16 as linearly polarized light in the direction perpendicular to the paper surface, and the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to be a straight line in the direction parallel to the paper surface. It becomes polarized light and is emitted from the polarizing plate 14 as linearly polarized light in a direction parallel to the paper surface. As described above, in the voltage-free portion, the incident external light is reflected instead of being absorbed by the polarizing separator 16, so that a bright reflection type display can be obtained. Since the light scatterer 15 is provided between the polarizing separator 16 and the TN liquid crystal panel 10, the reflected light from the polarizing separator 16 changes from a mirror surface to a white shape.

【0137】

In the voltage application section on the right side, when external light enters the display device 1400, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then transmitted through the TN liquid crystal 13 without changing the polarization direction. Then, the polarizing separator 16 also transmits without changing the polarization direction, and then the polarization state is changed by the scattering plate 140 to scatter. Most of the light scattered on the polarizing separator side by the scattering sheet 140 cannot pass through the polarizing separator because the polarization state is eliminated, resulting in a dark display.

【0138】

As described above, regarding the reflection type display when the external light is incident on the display device 1400, the light reflected by the polarizing separator 16 is transmitted through the light scatterer 15 and becomes a bright display in the voltage-free portion. In the voltage application section, the light transmitted through the polarizing separator 16 is scattered by the scattering plate 140 after changing the polarization state, resulting in a dark display.

【0139】

Then, in the voltage-free portion, the external light incident on the display device 1400 is reflected without being absorbed by the polarizing separator 16, so that a bright display can be obtained.

【0140】

Next, a transmission type display by light from the light source 17 will be described.

【0141】

In the no-voltage portion on the left side, the light from the light source 17 enters the polarizing separator 16 via the scattering plate 140, becomes linearly polarized light in the direction parallel to the paper surface by the polarizing separator 16, and then by the TN liquid crystal 13. The polarization direction is twisted by 90 ° to become linearly polarized light in the direction perpendicular to the paper surface, which is absorbed by the polarizing plate 14 to produce a dark display.

【0142】

In the voltage application section on the right side, the light from the light source 17 enters the polarizing separator 16 via the scattering plate 40, becomes linearly polarized light in the direction parallel to the paper surface by the polarizing separator 16, and is scattered by the light scattering body 15. After that, the TN liquid crystal 13 is transmitted without changing the polarization direction, and the polarizing plate 14 is also transmitted to obtain a bright display.

【0143】

As described above, regarding the transmission type display by the light from the light source 17, the light from the light source 17 is absorbed by the polarizing plate 14 in the voltage-unapplied portion and becomes a dark display, and the polarizing plate 14 is displayed in the voltage-applied portion. The display is transparent and bright.

【0144】

Therefore, this display device 1400 can display a bright reflection type by utilizing the reflection of the external light in a place where there is external light, and is a transmissive type by the light from the light source 17 even in a place where there is no external light. It is a reflection type display device having a so-called transflective type function capable of displaying.

【0145】

<Scattering plate> As the scattering plate used for the display device in this reference example, a scattering plate capable of emitting the incident light without eliminating the polarization state as much as possible is used. Since this scattering plate has a function of scattering and clouding the light emitted from the scattering plate, a display device having a cloudy display (white display) can be obtained. On the other hand, when the scattering plate 15 is removed from the configuration, the display device can obtain a glossy color display. Therefore, it is advisable to dispose of the scattering plate according to the application of the display device.

【0146】

<Light source> As the display device in this reference example, various light sources described in FIGS. 6 to 9 and the first reference example can be used. Since the action and effect are the same as those of the first reference example, the description thereof is omitted here.

【0147】

(First Embodiment) FIG. 16 is a cross-sectional view of the display device according to the first embodiment of the present invention, and FIG. 17 is a schematic cross-sectional view for explaining the display principle of the display device according to the first embodiment of the present invention.

【0148】

This display device 1600 can perform a reflection type display using the reflection of the external light in a place where there is external light, and also performs a transmissive type display by the light from the light source even in a place where there is no external light. It is a reflective display device having a so-called transflective function.

【0149】

<Basic structure> First, the structure of the display device of the present embodiment will be described with reference to FIG. In this display device 1600, a TN liquid crystal panel 10 is used as a transmission polarization axis variable optical element. In the TN liquid crystal panel 10, the TN liquid crystal 13 is sandwiched between the two glass plates 11 and 12, and a plurality of character display units (not shown) are provided so that the characters can be displayed. A polarizing sheet 14 is provided on the upper side of the TN liquid crystal panel 10. A light scatterer 15, a polarizing separator 16, a colored film 160 as a colored layer, and a light source 17 are provided in this order on the lower side of the TN liquid crystal panel 10. The colored film can be emitted by changing the polarization state of the incident light having a predetermined wavelength, and a transflective film capable of absorbing light having a wavelength other than the predetermined wavelength is used, and a white light source is used as the light source. A cold cathode tube was used. Further, a TAB board (not shown) on which a driver IC for driving the TN liquid crystal 13 is mounted is connected to the TN liquid crystal panel 10 to form a display device.

【0150】

<Polarizing separator> In this embodiment, the same one as described in the first reference example with reference to FIGS. 3 and 4 is used. The detailed description thereof will be omitted here. Of course, in addition to this polarizing separator, for example, a cholesteric liquid crystal layer sandwiched between λ / 4 plates, one that uses the angle of the brewer (SID 92DIGEST pages 427 to 429), one that uses holograms, etc. Has the same functions as the above-mentioned polarization separator, and they may be used in the display device of the present embodiment.

【0151】

<Display Principle> Next, with reference to FIG. 17, the display by the display device 1600 will be described with the right half of the display device 1600 as the voltage application section and the left half as the voltage non-application section.

【0152】

First, a reflective display when external light is incident on the display device 1600 will be described.

【0153】

In the voltage-free portion on the left side, when external light enters the display device 1600, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then the polarization direction is twisted by 90 ° by the TN liquid crystal 13. It becomes linearly polarized light in the direction perpendicular to the paper surface, is reflected by the polarizing separator 16 as linearly polarized light in the direction perpendicular to the paper surface, and the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to be a straight line in the direction parallel to the paper surface. It becomes polarized light and is emitted from the polarizing plate 14 as linearly polarized light in a direction parallel to the paper surface. As described above, in the voltage-free portion, the incident external light is reflected instead of being absorbed by the polarizing separator 16, so that a bright reflection type display can be obtained. Since the light scattering body 15 is provided in the question between the polarizing separator 16 and the TN liquid crystal panel 10, the reflected light from the polarizing separator 16 changes from a mirror surface shape to a white shape.

【0154】

In the voltage application section on the right side, when external light enters the display device 1600, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then transmitted through the TN liquid crystal 13 without changing the polarization direction. However, the polarizing separator 16 also transmits light without changing the polarization direction, and then the colored film 160 absorbs light within a predetermined wavelength range. Since the colored film absorbs light in a predetermined wavelength range, the display becomes dark.

【0155】

As described above, regarding the reflection type display when the external light is incident on the display device 1600, the light reflected by the polarizing separator 16 is transmitted through the light scattering body 15 and becomes a bright display in the voltage non-applied portion. In the voltage application section, the light transmitted through the polarizing separator 16 is absorbed by the coloring film 50, resulting in a dark display.

【0156】

Then, in the voltage-free portion, the external light incident on the display device 1600 is reflected without being absorbed by the polarizing separator 16, so that a bright display can be obtained.

【0157】

Next, a transmission type display by light from the light source 17 will be described.

【0158】

In the no-voltage portion on the left side, the light from the light source 17 enters the polarizing separator 16 via the colored film 160, becomes linearly polarized light in the direction parallel to the paper surface by the polarizing separator 16, and then by the TN liquid crystal 13. The polarization direction is twisted by 90 ° to become linearly polarized light in the direction perpendicular to the paper surface, which is absorbed by the polarizing plate 14 to produce a dark display.

【0159】

In the voltage application section on the right side, the light from the light source 17 is colored by passing through the colored film 160 and is incident on the polarizing separator 16, and the polarizing separator 16 becomes linearly polarized light in the direction parallel to the paper surface and scatters the light. It becomes scattered light by the body 15, and then transmits the TN liquid crystal 13 without changing the polarization direction, and also transmits the polarizing plate 14 to obtain a bright display.

【0160】

As described above, regarding the transmission type display by the light from the light source 17, the light from the light source 17 is absorbed by the polarizing plate 14 in the voltage-unapplied portion and becomes a dark display, and the polarizing plate 14 is displayed in the voltage-applied portion. The display is transparent and bright.

【0161】

Therefore, this display device 1600 can display a bright reflection type by utilizing the reflection of the external light in a place where there is external light, and is a transmissive type by the light from the light source 17 even in a place where there is no external light. It is a reflection type display device having a so-called transflective type function capable of displaying.

【0162】

<Scattering plate> As the scattering plate used in the display device of the present embodiment, a scattering plate capable of emitting light without eliminating the polarization state of the incident light is used. Since this scattering plate has a function of scattering and clouding the light emitted from the scattering plate, a display device having a cloudy display (white display) can be obtained. On the other hand, when the scattering plate 15 is removed from the configuration, the display device can obtain a glossy color display. Therefore, it is advisable to dispose of the scattering plate according to the application of the display device.

【0163】

<Colored layer> 18 and 19 show the display device of the present embodiment when various colored films are used as the colored layer. In this embodiment, any of the colored films shown in FIGS. 18 and 19 can be used. In the display device shown in FIG. 18, a colored film that transmits and reflects light having a red wavelength is used. In the display device shown in FIG. 18, the reflection type display has a blackish red display in the voltage application section and a white display in the voltage non-application section. On the other hand, regarding the transmission type display by the light from the light source, the light color of the light source colored by the colored film is displayed in the voltage application portion, that is, the display is red, and the display is black in the voltage non-application portion.

【0164】

By the way, when a colored film is not used and a light source that emits white light is used, as described above, the light from the light source 17 is displayed dark in the voltage-free portion and in the voltage-applied portion. A bright display can be obtained and a transmissive display can be obtained. At this time, when external light is incident from the front side of the display device, the external light causes a bright display in the voltage-unapplied portion, and the voltage is increased. The display is dark at the application part. As a result, in both the voltage non-applied part and the voltage applied part, for example, when the display by the transmitted light from the light source 17 is bright, the dark display of the reflection type by the external light is added and the display becomes gray, and the light source becomes a light source. Even if the display due to the transmitted light from 17 is dark, a bright display that is reflected by external light is added, and the display is also gray, which causes a so-called positive / negative inversion phenomenon, which may make the display difficult to see. is there.

【0165】

When the light source is turned on when the colored film shown in FIG. 18 is incident on external light, the light emitted from the light source 17 transmitted through the colored film 160 can be seen at the voltage application part, so that the display becomes grayish red and no voltage is marked. Since the external light reflected by the polarizing separator can be seen in the additional part, the display is gray, which is much easier to see than the simple black-and-white display.

【0166】

In FIG. 18, a colored film that reflects or transmits light having a red wavelength is used, but of course, light having a wavelength other than red may be used.

【0167】

In the display device shown in FIG. 19, a colored film having a region for reflecting and transmitting light having a red wavelength and a region for reflecting and transmitting light having a blue wavelength is arranged as a colored layer. Each region is arranged so that the emitted light corresponds to each character display unit formed on the liquid crystal panel. When the colored film shown in FIG. 19 is used in the display device of the present embodiment, the reflection type display is displayed in black in the voltage application section and white in the voltage non-application section. On the other hand, regarding the transmission type display by the light from the light source, in the voltage application section, each character display section displays the emission light color from each region of the corresponding colored film, that is, red or blue display, and in the voltage non-application section, It is displayed in black. When the light source shown in FIG. 19 is used to turn on the light source when external light is incident, each LE is applied to the voltage application unit. Since the emitted light from the D group can be seen, each character display unit has a grayish red or blue display, and in the no-voltage portion, the external light reflected by the polarizing separator can be seen, so that the display is gray. In FIG. 19, a colored film that transmits or reflects light of red wavelength and a colored film that reflects or transmits light of blue wavelength are used, but of course, a colored film that reflects or transmits light of wavelengths other than these colors is used. It does not matter, and the combination can be appropriately selected.

【0168】

(Second embodiment) FIG. 20 is a cross-sectional view of the display device according to the second embodiment of the present invention, and FIG. 21 is a schematic cross-sectional view for explaining the display principle of the display device according to the second embodiment of the present invention.

【0169】

This display device 2000 can perform a reflection type display using the reflection of the external light in a place where there is external light, and also performs a transmissive type display by light from a light source even in a place where there is no external light. It is a reflective display device having a so-called transflective function.

【0170】

<Basic Structure> First, the structure of the display device of the present embodiment will be described with reference to FIG. In this display device 2000, the TN liquid crystal panel 10 is used as the transmission polarization axis variable optical element. In the TN liquid crystal panel 10, the TN liquid crystal is sandwiched between two glass plates, and a plurality of character display units 201 and 202 are provided so that a character display can be performed. A polarizing plate 14 is provided on the upper side of the TN liquid crystal panel 10. On the lower side of the TN liquid crystal panel 10, a light scatterer 15, a polarizing separator 16, a gray transflective light absorber 200, a colored film 160 as a colored layer, and a light source 17 are provided in this order. Furthermore, a TAB board (not shown) on which a driver IC for driving the TN liquid crystal is mounted is frozen on the TN liquid crystal panel 10 to form a display device.

【0171】

<Polarizing separator> In this embodiment, the same one as described in the first reference example with reference to FIGS. 3 and 4 is used. The detailed description thereof will be omitted here. Of course, in addition to this polarizing separator, for example, a cholesteric liquid crystal layer sandwiched between λ / 4 plates, a worm that uses the angle of the brewer (SID 92DIGEST pp. 427-429), a hologram, etc. Has the same functions as the above-mentioned polarization separator, and they may be used in the display device of the present embodiment.

【0172】

<Display Principle> Next, the display by the display device 2000 will be described with reference to FIG. 21, with the right half of the display device 2000 as the voltage application section and the left half as the voltage non-application section.

【0173】

First, a reflective display when external light is incident on the display device 2000 will be described.

【0174】

In the voltage-free portion on the left side, when external light enters the display device 2000, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then the polarization direction is twisted by 90 ° by the TN liquid crystal 13. It becomes linearly polarized light in the direction perpendicular to the paper surface, is reflected by the polarization separator 16 as linearly polarized light in the direction perpendicular to the paper surface, and the polarization direction is twisted by 90 ° by TN Liquid Chang 13 in the direction parallel to the paper surface. It becomes linearly polarized light and is emitted from the polarizing plate 14 as linearly polarized light in a direction parallel to the paper surface. As described above, in the voltage-free portion, the incident external light is reflected instead of being absorbed by the polarizing separator 16, so that a bright reflection type display can be obtained. Since the light scatterer 15 is provided between the polarizing separator 16 and the TN liquid crystal panel 10, the reflected light from the polarizing separator 16 changes from a mirror surface to a white shape.

【0175】

In the voltage application section on the right side, when external light enters the display device 2000, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then transmitted through the TN liquid crystal 13 without changing the polarization direction. However, the polarizing separator 16 also transmits the light without changing the polarization direction, and then is absorbed by the light absorber 200 in the semi-transmissive state, resulting in a dark display.

【0176】

As described above, regarding the reflection type display when the external light is incident on the display device 2000, the light reflected by the polarizing separator 16 is transmitted through the light scatterer 15 and becomes a bright display in the voltage-free portion. In the voltage application section, the light transmitted through the polarizing separator 16 is absorbed by the light absorber 160 in the semitransmissive state, resulting in a dark display.

【0177】

Then, in the voltage-free portion, the external light incident on the display device 2000 is reflected without being absorbed by the polarizing separator 16, so that a bright display can be obtained.

【0178】

Next, a transmission type display by light from the light source 17 will be described.

【0179】

In the no-voltage portion on the left side, the light from the light source 17 is colored by passing through the coloring film 160, passes through the light absorber 200 in the semitransmissive state, enters the polarizing separator 16, and is incident on the polarizing separator 16 by the polarizing separator 16. It becomes linearly polarized light in the direction parallel to the paper surface, and then the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to become linearly polarized light in the direction perpendicular to the paper surface, which is absorbed by the polarizing plate 14 to produce a dark display.

【0180】

In the voltage application section on the right side, the light from the light source 17 passes through the coloring film 160 and is colored, passes through the light absorber 200 in the semitransparent state, enters the polarizing separator 16, and is incident on the polarizing separator 16 by the polarizing separator 16. It becomes linearly polarized light in the direction parallel to the paper surface, becomes scattered light by the light scattering body 15, and then transmits the TN liquid crystal 13 without changing the polarization direction, and also transmits the polarizing plate 14 to obtain a bright display.

【0181】

As described above, regarding the transmission type display by the light from the light source 17, the light from the light source 17 is absorbed by the polarizing plate 14 in the voltage-unapplied portion and becomes a dark display, and the polarizing plate 14 is displayed in the voltage-applied portion. The display is transparent and bright.

【0182】

Therefore, this display device 2000 can display a bright reflection type by utilizing the reflection of the external light in a place where there is external light, and is a transmissive type by the light from the light source 17 even in a place where there is no external light. It is a reflection type display device having a so-called transflective type function capable of displaying.

【0183】

<Light Absorber> In the light absorber 200 in the present embodiment, in addition to the light absorber in the semitransmissive state, the same one as that used in the second embodiment, that is, a black light absorber. It is also possible to use the one provided with an opening. Then, by limiting the ratio of the opening to the light absorber, the decrease in contrast can be suppressed as in the second embodiment. Of course, as in the second embodiment, a polarizing plate having a different absorption axis from the polarizing separator 16 can also be used.

【0184】

<Colored layer> In the display device of the present embodiment, various colored films described in FIGS. 18 and 19 and the first embodiment can be used as the colored layer. Since the action and effect are the same as in the first implementation, the description thereof is omitted here.

【0185】

(Third embodiment) FIG. 22 is a cross-sectional view of the display device according to the third embodiment of the present invention, and FIG. 23 is a schematic cross-sectional view for explaining the display principle of the display device according to the third embodiment of the present invention.

【0186】

This display device 2200 can perform a reflective display using the reflection of the external light in a place where there is external light, and also performs a transmissive display by the light from the light source even in a place where there is no external light. It is a reflective display device having a so-called transflective function.

【0187】

<Basic structure> First, the structure of the display device of the present embodiment will be described with reference to FIG. In this display device 2200, a TN liquid crystal panel 10 is used as a transmission polarization axis variable optical element. In the TN liquid crystal panel 10, the TN liquid crystal is sandwiched between two glass plates, and a plurality of character display units 201 and 202 are provided so that character display is possible. A polarizing plate 14 is provided on the upper side of the TN liquid crystal panel 10. On the lower side of the TN liquid crystal panel 10, a polarizing separator 16, a colored film 160 as a coloring layer, a reflector 220 having an opening, and a light source 17 are provided in this order. The reflector 220 is provided with a plurality of openings 221 having a predetermined area density. Furthermore, a TAB board (not shown) on which a driver IC for driving the TN liquid crystal is mounted is connected to the TN liquid crystal panel 10 to form a display device.

【0188】

<Polarizing separator> In this embodiment, the same one as described in the first reference example with reference to FIGS. 3 and 4 is used. The detailed description thereof will be omitted here. Of course, in addition to this polarizing separator, for example, a cholesteric liquid crystal layer sandwiched between λ / 4 plates, one that uses the angle of the brewer (SID 92DIGEST pages 427 to 429), one that uses holograms, etc. Has the same functions as the above-mentioned polarization separator, and they may be used in the display device of the present embodiment.

【0189】

<Display Principle> Next, the display by the display device 2200 will be described with reference to FIG. 23, with the right half of the display device 2200 as the voltage application section and the left half as the voltage non-application section.

【0190】

First, a reflective display when external light is incident on the display device 2200 will be described.

【0191】

In the voltage-free portion on the left side, when external light enters the display device 2200, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then the polarization direction is 90 ° by the TN liquid crystal 13. It becomes linearly polarized light in the direction perpendicular to the paper surface, is reflected by the polarizing separator 16 as linearly polarized light in the direction perpendicular to the paper surface, and the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to be a straight line in the direction parallel to the paper surface. It becomes polarized light and is emitted from the polarizing plate 14 as linearly polarized light in a direction parallel to the paper surface. As described above, in the voltage-free portion, the incident external light is reflected instead of being absorbed by the polarizing separator 16, so that a bright reflection type display can be obtained.

【0192】

In the voltage application section on the right side, when external light enters the display device 2200, the external light is linearly polarized in the direction parallel to the paper surface by the polarizing plate 14, and then transmitted through the TN liquid crystal 13 without changing the polarization direction. However, the polarizing separator 16 also transmits without changing the polarization direction, and a part of it is reflected by the colored layer 160 and passes through the polarizing separator 160 again, and the TN liquid crystal remains linearly polarized in the direction parallel to the paper surface. 140 is transmitted without changing the polarization direction, is absorbed by the colored layer 160 and is transmitted through the colored layer 160, is reflected by the reflector 220, and then is absorbed by the colored layer 160 again and is transmitted through the colored layer 160, and is polarized. The separator 16 is transmitted again, the TN liquid crystal 13 is transmitted as linearly polarized light in the direction parallel to the paper surface without changing the polarization direction, and is emitted from the polarizing plate 14 as linearly polarized light in the direction parallel to the paper surface, resulting in a colored display. ..

【0193】

Next, a transmission type display by light from the light source 17 will be described.

【0194】

In the no-voltage portion on the left side, the light from the light source 17 enters the polarizing separator 16 while being colored by the colored film through the opening 221 provided in the reflector 220, and is parallel to the paper surface by the polarizing separator 16. After that, the polarization direction is twisted by 90 ° by the TN liquid crystal 13 to become linearly polarized light in the direction perpendicular to the paper surface, which is absorbed by the polarizing plate 14 to produce a dark display.

【0195】

In the voltage application section on the right side, the light from the light source 17 passes through the opening 221 provided in the reflector 200, enters the polarizing separator 16 while being colored by the colored layer 160, and is placed on the paper surface by the polarizing separator 16. Linearly polarized light in the parallel direction is obtained, and then the TN liquid crystal 13 is transmitted without changing the polarization direction, and the polarizing plate 14 is also transmitted to obtain a colored and bright display.

【0196】

As described above, regarding the transmission type display by the light from the light source 17, the light from the light source 17 is absorbed by the polarizing plate 14 in the voltage-unapplied portion and becomes a dark display, and the polarizing plate 14 is displayed in the voltage-applied portion. The display is transparent and bright.

【0197】

Therefore, this display device 2200 can display a bright reflection type by utilizing the reflection of the external light in a place where there is external light, and is a transmissive type by the light from the light source 17 even in a place where there is no external light. It is a reflection type display device having a so-called transflective type function capable of displaying.

【0198】

<Reflector> An Al reflector or the like can be used as the display device in the present embodiment. Further, in addition to the reflector provided with the opening, a half mirror or the like may be used.

【0199】

<Colored layer> As the display device in the present embodiment, various colored films described in FIGS. 18, 19 and the first embodiment can be used. Since both the action and the effect are the same as those in the first embodiment, the description thereof will be omitted here.

【0200】

(Fourth Embodiment) FIG. 25 is a perspective view of a mobile phone using the display devices introduced in the first to fifth reference examples of the present invention and the first to third embodiments as its display unit. Is. In the figure, (a) shows a mobile phone and (b) shows a wristwatch.

【0201】

In the present embodiment, a mobile phone and a wristwatch are shown, but the display device of the present invention can be used for various electronic devices such as a personal computer, a car navigation system, and an electronic organizer.

【0202】

In the first to fifth reference examples and the first to fourth embodiments described above, only the dark display, the bright display, and the color display have been described, but the display devices of the respective embodiments have halftones. It is natural that the display can be performed.

【0203】

Further, in the first to fifth reference examples and the first to fourth embodiments, the TN liquid crystal panel 10 has been described as an example of the transmission polarization axis variable means, but the STN liquid crystal element and the ECB liquid crystal element have been described. Etc. can also be used. As the STN liquid crystal element, an STN liquid crystal element using an optically anisotropic substance for color compensation such as an F-STN liquid crystal element is preferably used.

【0204】

Further, in the first to fifth reference examples and the first to fourth embodiments, preferably, by increasing the distance between the polarizing separator and the light source, the light is reflected by the light source and returned again. The amount of light coming can be reduced, and the decrease in contrast can be suppressed. [0205]

Further, in the second to fifth reference examples and the second and third embodiments, the light transmitted through the light absorber is also obtained by increasing the distance between the light absorber or the scattering plate and the light source. The amount of light reflected by the light source and returned again can be reduced, and the decrease in contrast can be suppressed.

【0206】

Further, in the first to fifth reference examples and the first to third embodiments, by darkening the surface color of the light source, the reflection on the surface of the light source can be suppressed, and as a result, light absorption can be suppressed. The amount of light that has passed through the body is reflected by the light source and returned again can be reduced, and a decrease in contrast can be suppressed.

【0207】

In the second to fifth reference examples and the second embodiment, the bright display by the light reflected by the polarizing separator side is the display by the light reflected by the polarizing separator side. It is not affected by the structure of the light absorber located behind this polarizing separator.

【0208】

Further, in the display devices shown in the first to fifth reference examples, a means for concentrating the light from the light source toward the front surface of the display device may be further provided.

【0209】

Normally, when viewing a reflection type display by external light, the display is performed at a position inclined by a certain angle from the normal line to the front of the display device. This is because if viewed from the normal direction to the front of the display device, the observer himself blocks the external light incident on the display device, so that the reflection type display by the external light becomes dark. On the other hand, when viewing the display by the transmitted light from the light source, it is usually viewed from the normal direction to the front of the display device, so a means for condensing the light from the light source toward the front of the display device is provided. By providing, the display by the transmitted light from the light source can be brightened, and as a result, the transmitted display by the light from the light source becomes easy to see in the normal direction to the front of the display device. As a means for condensing the light from the light source toward the front of the display device, for example, a prism sheet is preferably used. Regarding the position where the prism sheet is arranged, it is preferable to provide the light source and the polarizing separator in the first to fifth reference examples, and in the first to third embodiments, the light source is as shown in FIG. 24. It is preferable to provide the prism sheet 230 between the and the colored film.

【0210】

In the display device of the present invention, light incident from the outside of the first polarization separating means is reflected from the second polarization separating means according to the state of the transmission polarization axis of the transmission polarization axis variable means. Two display states, a first display state due to the generated light and a second display state in which the light transmitted through the second polarization separating means is absorbed by the optical element, are obtained, and are of a reflective type. It becomes a display device. The first display state is a display state due to the light reflected from the second polarization separating means, so that the display is bright.

【0211】

Further, with respect to the light from the light source, the third display state and the first polarization separation by the light transmitted through the first polarization separation means are obtained according to the state of the transmission polarization axis of the transmission polarization axis variable means. Two display states, that is, a fourth display state in which light does not pass through the means, can be obtained, and a transmission type display can be obtained.

【0212】

As described above, in the display device of the present invention, a bright reflection type display utilizing the reflection of the external light can be performed in a place where there is external light, and even in a place where there is no external light, the display can be transmitted from the light source. It is possible to display a transmissive type by light.

【0213】

Then, the second polarization separating means uses the linearly polarized light component in the third predetermined direction of the light incident from the transmission polarization axis variable means side with respect to the light in almost the entire wavelength range of the visible light region. It is transmitted to the optical element side, and the linearly polarized light component in the fourth predetermined direction orthogonal to the third predetermined direction is reflected to the transmitted polarization axis variable means side, and has almost the entire wavelength range of the visible light region. By providing a polarizing separation means capable of emitting linearly polarized light in the third predetermined direction to the transmission polarization axis variable means side with respect to the light incident from the optical element side, the entire visible light region can be obtained. The first to fourth display states can be obtained for light in the wavelength range, and transparent or bright display can be obtained in the first and third display states.

【0214】

Further, by using the optical element as an optical element that absorbs light in almost the entire wavelength range of the visible light region, and particularly using a black light absorber, it is possible to obtain a dark display in the second and fourth display states. it can.

[Simple explanation of drawings]

[Figure 1]

It is sectional drawing of the display device in the 1st reference example of this invention.

[Figure 2]

It is schematic cross-sectional view for demonstrating the display principle of the display device of the 1st reference example of this invention.

[Fig. 3]

It is a schematic block diagram of the polarization separator 16 used in this invention.

[Fig. 4]

It is a figure explaining the operation of the polarization separator 16 shown in FIG.

[Fig. 5]

It is a figure which shows the example of the light source used in this invention.

[Fig. 6]

It is a figure which shows another example of the light source used in this invention.

[Fig. 7]

It is a figure which shows another example of the light source used in this invention.

[Fig. 8]

It is a figure which shows another example of the light source used in this invention.

[Fig. 9]

It is a figure which shows another example of the light source used in this invention.

[Fig. 10]

It is sectional drawing of the display device in the 2nd reference example of this invention.

[Fig. 11]

It is schematic cross-sectional view for demonstrating the display principle of the display device of the 2nd reference example of this invention.

[Fig. 12]

It is the schematic sectional drawing for demonstrating the display device of the 3rd reference example of this invention.

[Fig. 13]

It is the schematic sectional drawing for demonstrating the display device of the 4th reference example of this invention.

[Fig. 14]

It is sectional drawing of the display device in 5th reference example of this invention.

[Fig. 15]

It is schematic cross-sectional view for demonstrating the display principle of the display device of the 1st reference example of this invention.

[Fig. 16]

It is sectional drawing of the display device in 1st Embodiment of this invention.

[Fig. 17]

It is schematic cross-sectional view for demonstrating the display principle of the display device of 1st Embodiment of this invention.

[Fig. 18]

It is a figure which shows the example of the colored layer used in this invention.

[Fig. 19]

It is a figure which shows another example of the colored layer used in this invention.

[Fig. 20]

It is sectional drawing of the display device in 2nd Embodiment of this invention.

[Fig. 21]

It is schematic cross-sectional view for demonstrating the display principle of the display device of the 2nd Embodiment of this invention.

[Fig. 22]

It is sectional drawing of the display device in 3rd Embodiment of this invention.

[Fig. 23]

It is schematic cross-sectional view for demonstrating the display principle of the display device of the 3rd Embodiment of this invention.

[Fig. 24]

It is a figure which shows the example which combined the prism sheet with the display device of this invention.

[Fig. 25]

It is a figure which shows the example of the electronic device which includes the display device of this invention as a display part.

[Fig. 26]

It is a figure which shows the example of the conventional display device.