Optical film

Optical film

OPTICAL FILM

The present invention relates to an optical film, and particularly relates to an optical film with better quality and higher tunability.

With the advancement of semiconductor technology, today's light-emitting diodes have been equipped with high-brightness output. In addition, light-emitting diodes have the advantages of power saving, small size, low-voltage drive, and no mercury. Therefore, light-emitting diodes have been It is widely used in the fields of display and lighting. Due to the continuous expansion of the application level, the demand for the color of the light source generated by the light-emitting diode is gradually diversified. In addition, the quality requirements for the color temperature (Correlated Color Temperature, CCT) and color rending index (CRI) shown by the light-emitting diodes are also getting higher and higher.

In the patent certificate No. M318797, a method of forming an optical film is proposed. 1 is a schematic diagram of a conventional light emitting diode package structure with optical film. The light emitting diode package structure 100 includes a substrate 110, a light emitting diode chip 120, a lens 130, and an optical film 140. The substrate 110 has a groove 112 and a circuit layer 114. The light emitting diode chip 120 is disposed on the substrate 110 and is electrically connected to the circuit layer 114 on the substrate 110 by wire bonding. The optical film 140 is disposed above the groove 112 of the substrate 110, and the lens 130 is disposed on the optical film 140. Among them, the optical film 140 is made of transparent glue or transparent plastic material and phosphor powder according to an appropriate ratio and mixed uniformly to form a film. The shape is formed.

The phosphor contained in the optical film 140 is excited by the light emitted by the light-emitting diode chip 120 to generate secondary light. The secondary light and the light emitted by the light-emitting diode chip 120 can be mixed to form light of other specific wavelengths. Therefore, the light emitted by the light emitting diode package structure 100 is more diverse. However, during the manufacturing process of the optical film 140, since the uniformity is not easy to control, it is easy to cause phosphor precipitation or uneven mixing. As a result, the poor quality of the optical film 140 will affect the color temperature and color rendering performance of the light emitted by the light emitting diode package structure 100. In other words, the optical film plays an important key role in the performance of the light source of the light emitting diode package structure.

The present invention provides an optical film having multiple fluorescent layers stacked on each other.

The present invention provides another optical film, which has a plurality of patterned phosphor layers arranged in an array.

The present invention provides an optical film including multiple fluorescent layers stacked on top of each other. Each phosphor layer will be separately excited under the illumination of the excitation light source to emit secondary rays of different wavelength ranges.

In an embodiment of the present invention, the optical film further includes a first substrate, and the above-mentioned phosphor layer is stacked on the first substrate.

In an embodiment of the present invention, the wavelength of the excitation light source is smaller than the wavelength of each secondary light.

In an embodiment of the present invention, the first substrate is a transparent substrate. Other In addition, in other embodiments of the present invention, the first substrate is a reflective substrate.

In an embodiment of the present invention, the fluorescent layer includes at least two of a red fluorescent layer, a green fluorescent layer, and a yellow fluorescent layer.

In an embodiment of the present invention, the phosphor layer at the bottom of the phosphor layer covers the surface of the first substrate completely.

In an embodiment of the present invention, the optical film further includes a second substrate, wherein the second substrate covers the topmost phosphor layer in the phosphor layer, so that the phosphor layer is located on the first substrate and Between the second substrate.

In an embodiment of the present invention, when the first substrate is a transparent substrate, the second substrate may be a transparent substrate or a reflective substrate. In other embodiments of the present invention, when the first substrate is a reflective substrate, the second substrate may be a transparent substrate.

The present invention provides another optical film, which includes a plurality of patterned phosphor layers arranged in an array. Each of the patterned phosphor layers emits secondary light in different wavelength ranges under the illumination of the excitation light source.

In an embodiment of the present invention, the optical film further includes a first substrate, and the patterned phosphor layer is stacked on the first substrate.

In an embodiment of the present invention, the wavelength of the excitation light source is smaller than the wavelength of each secondary light.

In an embodiment of the present invention, the first substrate is a transparent substrate. In other embodiments of the present invention, the first substrate is a reflective substrate.

In an embodiment of the present invention, the patterned fluorescent layer includes at least two of a patterned red fluorescent layer, a patterned green fluorescent layer, and a patterned yellow fluorescent layer.

In an embodiment of the present invention, the patterned phosphor layer covers the first substrate Different areas on the surface of the substrate, and the patterned phosphor layer will fully cover the surface of the first substrate.

In an embodiment of the present invention, the optical film further includes a second substrate. The second substrate covers the patterned fluorescent layer, so that the patterned fluorescent layer is located between the first substrate and the second substrate.

In an embodiment of the present invention, when the first substrate is a transparent substrate, the second substrate may be a transparent substrate or a reflective substrate. Conversely, when the first substrate is a reflective substrate, the second substrate is a transparent substrate.

In an embodiment of the present invention, the patterned phosphor layer is in a matrix arrangement.

In an embodiment of the present invention, the patterned phosphor layer is in a delta arrangement.

In an embodiment of the present invention, the patterned phosphor layer is in a honeycomb arrangement.

Based on the above, the optical film of the present invention has multiple fluorescent layers stacked on top of each other or patterned fluorescent layers arranged in an array, and each fluorescent layer emits secondary rays of different wavelength ranges when irradiated by excitation light. The secondary light of different wavelength ranges is mixed to form light of a specific wavelength range. In addition, the optical film has multiple or multiple fluorescent layers, so the tunability is high, and the wavelength range of the light that can be formed is also more diverse.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

2A to 2E are the manufacturing of an optical film according to an embodiment of the present invention Schematic diagram of the process. Please refer to FIG. 2A. First, a first substrate 210 is provided. In this embodiment, the first substrate 210 may be a transparent substrate or a reflective substrate. In addition, the first substrate 210 may be a rigid substrate or a flexible substrate.

Please refer to FIG. 2B, then the phosphor and the volatile solvent are mixed uniformly, and the mixed substance is coated on the first substrate 210. In this embodiment, the phosphor coating method is, for example, by printing to uniformly distribute the mixture of phosphor and solvent on the first substrate 210, as shown in FIG. 2B.

Next, as shown in FIG. 2C, after the solvent evaporates, the remaining phosphor forms a phosphor layer 200a. According to the requirements at the time of implementation, the steps of FIG. 2B to FIG. 2C can be repeated to form a multi-layered phosphor layer such as 200a, 200b, 200c. In particular, the order in which the phosphor layers 200a, 200b, and 200c are formed and the thickness of the phosphor layers 200a, 200b, and 200c are not limited, and can be changed depending on the needs of the implementation. In FIG. 2D of the present embodiment, only three phosphor layers 200a, 200b, and 200c are shown as a representative description. In this embodiment, the thickness of the phosphor layers 200a, 200b, and 200c is preferably in the range of 0.5 micrometers (μm) to 1 millimeter (mm).

2E, after the above steps are completed, the second substrate 220 can be selectively covered on the topmost phosphor layer 200c, so that all the phosphor layers 200a, 200b, 200c are located on the first substrate 210 and Between the second substrate 220. The function of the second substrate 220 is to protect the fluorescent layers 200a, 200b, and 200c, so as to reduce the possibility of damage to the fluorescent layers 200a, 200b, and 200c. The second substrate 220 of this embodiment is, for example, a reflective substrate or a transparent substrate. In addition, the second substrate 220 can be a rigid substate or a flexible substrate. Substrate (flexible substrate). It should be noted that when the first substrate 210 is a transparent substrate, the second substrate 220 can be a reflective substrate or a transparent substrate. However, when the first substrate 210 is a reflective substrate, the second substrate 220 may be a transparent substrate.

In this embodiment, after the above steps are completed, the fluorescent layers 200a, 200b, and 200c can be selectively peeled off or released from the first substrate 210 to form an optical film 200 having multiple fluorescent layers 200a, 200b, and 200c. . In more detail, the optical film 200 composed of the phosphor layers 200a, 200b, and 200c alone has advantages in thickness, weight, and volume without the first substrate 210 and the second substrate 220.

FIG. 3 is a schematic diagram of another method of coating phosphors in this embodiment. 3, in addition to the printing method shown in FIG. 2B, the method of coating the phosphor on the first substrate 210 can also be sprayed. It is worth noting that the thickness of the phosphor layer formed can be changed according to the needs of the actual situation, regardless of whether it is printed or sprayed. In this embodiment, the preferred range of the thickness of the phosphor layer is medium Between 0.5 microns (μm) and 1 millimeter (mm).

Please continue to refer to FIG. 2E, the optical film formed by the above-mentioned manufacturing process includes a plurality of phosphor layers 200a, 200b, and 200c stacked on each other. The phosphor layers 200a, 200b, and 200c are respectively excited by the excitation light source to emit secondary light in different wavelength ranges. Generally speaking, the wavelength of the excitation light source is smaller than the wavelength of each secondary light. In this embodiment, the fluorescent layer 200a is, for example, a red fluorescent layer, the fluorescent layer 200b is, for example, a green fluorescent layer, and the fluorescent layer 200c is, for example, a yellow fluorescent layer. Each fluorescent layer 200a, There are different phosphors in 200b and 200c respectively. In this embodiment, the wavelength band in which the phosphor layers 200a, 200b, and 200c can be excited is, for example, between 380 nanometers (nm) and 700 nanometers.

Because the thickness of the multilayer phosphor layers 200a, 200b, and 200c included in the optical film 200 will affect the optical properties of the optical film 200. Therefore, by controlling the thickness of the phosphor layers 200a, 200b, and 200c, the optical properties of the optical film 200 can be changed.

In order to facilitate the access of the optical film 200, the optical film 200 of this embodiment may include a first substrate 210 to enhance the structural strength of the optical film 200 itself. The phosphor layer 200a at the bottom layer will fully cover the surface of the first substrate 210. In addition to the first substrate 210, in order to make the optical film 200 less susceptible to damage, the optical film 200 may further include a second substrate 220. Wherein, the second substrate 200 covers the topmost phosphor layer 200c, so that the phosphor layers 200a, 200b, and 200c are located between the first substrate 210 and the second substrate 220. Regarding the selection of materials that can be used for the first substrate 210 and the second substrate 220 and the conditions that need to be paid attention to when matching, refer to the relevant description above, and the description will not be repeated here.

4A to 4D are schematic diagrams of a manufacturing method of an optical film according to another embodiment of the present invention. Please refer to FIG. 4A, the manufacturing method of the optical film in this embodiment is similar to the manufacturing method shown in FIGS. 2A to 2D, but the main difference between the two is that the phosphor is coated on the first substrate in this embodiment Before 210, a patterned mask layer 310 is first disposed on the first substrate 210 to expose part of the surface 212 of the first substrate 210.

Please refer to FIG. 4B, and then apply phosphor to the unmasked layer 310 A patterned phosphor layer 300a is formed on the shielded first substrate 210, and the portion of the first substrate 210 that is shielded by the mask layer 310 will not have phosphor.

Referring to FIG. 4C, the mask layer 310 is moved to expose other parts of the surface of the first substrate 210. It is worth noting that the portion of the first substrate 210 where the patterned phosphor layer 300 a has been formed will be covered by the mask layer 310.

Then repeat the steps of FIG. 4B to coat another different phosphor on the first substrate 210 to form another patterned phosphor layer 300b. In this embodiment, the steps of FIG. 4B to FIG. 4C may be repeated for an unlimited number of times to form a plurality of patterned phosphor layers 300a, 300b, and 300c arranged in an array as shown in FIG. 4D. FIG. 4D only shows three different patterned phosphor layers 300a, 300b, and 300c as representative for illustration.

Similar to the manufacturing method of the optical film in the previous embodiment, the steps of the manufacturing method of this embodiment may also include selectively forming a second substrate 220 to cover the patterned phosphor layers 300a, 300b, 300c Above, the patterned phosphor layers 300a, 300b, and 300c are located between the first substrate 210 and the second substrate 220. In other embodiments, the patterned phosphor layers 300a, 300b, and 300c can also be selectively peeled or released from the first substrate 210 to form a patterned phosphor layer 300a with a plurality of arrays. 300b, 300c optical film 300.

Referring to FIG. 4D, the optical film 300 formed by the above-mentioned manufacturing method includes a plurality of patterned phosphor layers 300a, 300b, and 300c arranged in an array. Each of the patterned phosphor layers 300a, 300b, and 300c will respectively emit secondary light in different wavelength ranges when illuminated by the excitation light source. Excitation light of this embodiment The wavelength of the source is smaller than the wavelength of each secondary light. The patterned fluorescent layer 300a in this embodiment is, for example, a patterned red fluorescent layer, the fluorescent layer 300b is, for example, a patterned green fluorescent layer, and the fluorescent layer 300c is, for example, a patterned yellow fluorescent layer. The thickness, coverage area, and coverage position of the phosphor layer are not limited, and can be changed according to the needs of the actual situation at the time of implementation. However, only three patterned phosphor layers 300a, 300b, and 300c are shown in FIG. 4D as a representation.

Please continue to refer to FIG. 4D, the optical film 300 of this embodiment may include a first substrate 210, and the patterned phosphor layers 300a, 300b, and 300c are stacked on the first substrate 210. In this embodiment, the patterned phosphor layers 300a, 300b, and 300c cover different areas on the surface 212 of the first substrate 210.

5A and 5B are top views of the patterns of two patterned phosphor layers in an embodiment of the present invention. Referring to FIGS. 5A and 5B at the same time, according to the patterns on the mask layer 310, the formed patterned phosphor layers 300a, 300b, and 300c have different patterns, such as a matrix arrangement as shown in FIG. 5A. ), the honeycomb arrangement or delta arrangement as shown in FIG. 5B.

In the above-mentioned embodiments, the structures of the two optical films and the manufacturing methods of the two optical films are respectively introduced. In the following embodiments, the implementation of the above-mentioned optical film applied to the light-emitting diode package structure will be illustrated in detail.

FIG. 6 is a schematic diagram of a light emitting diode package structure according to another embodiment of the present invention. Referring to FIG. 6, the light emitting diode package structure 400a of this embodiment includes a substrate 410, a light emitting diode chip 420, and an optical film 430a. The substrate 410 has a cavity 412 and a circuit layer 414, The groove 412 exposes part of the circuit layer 414. The light emitting diode chip 420 is disposed at the bottom of the groove 412 and is electrically connected to the circuit layer 414. The electrical connection between the light emitting diode chip 420 and the circuit layer 414 is, for example, wire bonding or flip chip.

In this embodiment, the optical film 430a is, for example, the optical film 200 of the above-mentioned embodiment. The optical film 430a includes multiple stacked fluorescent layers, and the fluorescent layers emit different wavelength ranges after being excited. Therefore, light of a specific wavelength range can be formed by mixing light.

In FIG. 6 of this embodiment, only one light-emitting diode chip 420 is shown as a representation. However, the present invention is not limited to this. The number of light-emitting diode chips 420 and the wavelength emitted by the light-emitting diode chips can be adjusted according to the actual situation at the time of implementation. Whats more noteworthy is that the combination of the wavelength emitted by the light-emitting diode chip 420 and the characteristics that different phosphor layers in the optical film 430a can be excited to produce different wavelength ranges will make the light emitted by the light-emitting diode package structure 400a The tunability is increased. In addition, due to the high tunability of the optical film 430a, the color temperature and color rendering of the light emitted by the light emitting diode package structure 400a can be adjusted to increase the margin.

FIG. 7 is a schematic diagram of a light-emitting diode package structure according to another embodiment of the present invention. Referring to FIG. 7, the light emitting diode package structure 400b of this embodiment is similar to the light emitting diode package structure 400a of the previous embodiment. The biggest difference between the two is that the optical film 430b of this embodiment further includes a first substrate 432a.

FIG. 8 is a light-emitting diode package structure according to another embodiment of the present invention Schematic diagram. Please refer to FIG. 8, the light-emitting diode package structure 400c of this embodiment is similar to the above-mentioned light-emitting diode package structure 400a. However, the optical film 430c of the light emitting diode package structure 400c of this embodiment is, for example, an optical film 300 having a plurality of patterned fluorescent layers arranged in an array.

In FIG. 8 of this embodiment, only one light-emitting diode chip 420 is shown as an expression. However, the present invention is not limited to this. In a preferred embodiment, the configuration of the light-emitting diode chip 420 can correspond to the patterning on the optical film 430c to form a plurality of sub-regions, and the sub-regions can each mix light. Forms light of different wavelengths.

FIG. 9 is a schematic diagram of another light emitting diode package structure according to another embodiment of the present invention. Please refer to FIG. 9, the light emitting diode package structure 400d of this embodiment is similar to the light emitting diode package structure 400c of the previous embodiment. The only difference is that the optical film 430d of this embodiment further includes a first substrate 432a and a second substrate 432b. The first substrate 432a and the second substrate 432b can provide a protective effect and reduce the probability of damage to the optical film 430d during the manufacturing process or when used by consumers.

In the above embodiments of FIGS. 6 to 9, the light emitting diode chip 420 is taken as an example for description. However, the present invention is not limited to this, and what is disposed in the groove 412 can also be, for example, a light emitting diode package structure including a lens to form a package in package (PiP) structure. In addition, the light-emitting diode chip 420 can also be replaced with other suitable light-emitting elements.

In summary, the optical film of the present invention has multiple phosphor layers, and each phosphor layer emits secondary light in different wavelength ranges when irradiated by excitation light. Wire. The secondary light of different wavelength ranges is mixed to form light of a specific wavelength range. Due to the high tunability of the optical film, the wavelength range of the light that can be formed is also more diversified. In addition, in some embodiments of the present invention, when the optical film is applied to the light emitting diode packaging structure, the light emitted by the light emitting diode packaging structure can have different color temperatures and better color rendering properties.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, The protection scope of the present invention shall be subject to those defined by the attached patent application scope.

<p>100, 400a, 400b, 400c, 400dLight-emitting diode package structure</p><p>110,410Substrate</p><p>112, 412 groove</p><p>114, 414Circuit layer</p><p>120, 420LED chip</p><p>130Lens</p><p>140, 200, 300, 430a, 430b, 430c, 430dOptical film</p><p>200a, 200b, 200c, 300a, 300b, 300cFluorescent layer</p><p>210,432aFirst substrate</p><p>220,432bSecond base material</p><p>310Curtain layer</p>

FIG. 1 is a schematic diagram of a conventional light emitting diode package structure with optical film.

2A to 2E are schematic diagrams of a manufacturing process of an optical film according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of another method of coating phosphors in this embodiment.

4A to 4D are schematic diagrams of a manufacturing method of an optical film according to another embodiment of the present invention.

5A and 5B are top views of the patterns of two patterned phosphor layers in an embodiment of the present invention.

FIG. 6 is a schematic diagram of a light emitting diode package structure according to another embodiment of the present invention.

FIG. 7 is a schematic diagram of a light-emitting diode package structure according to another embodiment of the present invention.

FIG. 8 is a schematic diagram of a light emitting diode package structure according to another embodiment of the present invention.

FIG. 9 is a schematic diagram of another light emitting diode package structure according to another embodiment of the present invention.