Display device

The present invention relates to a display device, and more particularly to a foldable display device in which a joint between two or more interconnected display panels is invisible.

Recently, mobile multimedia broadcasting services such as DMB (Digital Multimedia Broadcasting) have begun to be provided, and small mobile devices such as mobile phones and portable display devices such as Portable Multimedia Player (PMP). There is an increasing need to increase the size of the display panel as much as possible. However, as the size of the display panel increases, there is a problem that the portability is greatly reduced.

As a result, as shown in FIG. 1, a foldable display device (foldable display) in which two display panels 10a and 10b are joined to each other so as to be foldable when carried. device) has been proposed. However, in such a foldable display device, the distance between the pixels 12a and 12b arranged on the joint side of the two display panels is about 1 mm, so that the images displayed on the two display panels are displayed. There is a problem that the black stripe B can be seen in between. In order to minimize the black stripe B, it is necessary to minimize the distance between the pixels 12a and 12b arranged on the joint side of the two display panels, respectively. However, due to the thickness of the partition walls 11a and 11b for completely sealing the pixels inside the display panel from the outside, the distance between the pixels 12a and 12b arranged on the joint side of the two display panels, respectively, has been conventionally increased. I couldn't reduce it enough. Such a problem occurs not only in a folder-type display device having portability but also in a case where a plurality of relatively small display panels are connected to form a large display device having a large screen.

In order to improve such a problem, a technology capable of removing black stripes and providing a continuous image without reducing the distance between pixels 12a and 12b arranged on the joint side of two display panels, respectively, is available. was suggested. FIG. 2 illustrates an exemplary display device in which the seams between two display panels are hidden. Referring to FIG. 2, two display panels 20a and 20b are interconnected through a junction 21. Here, in order to optically compensate for the seam between the two display panels 20a and 20b, the electrode 25 near the joint portion 21 is formed smaller than the electrode 24 in the other portion. Then, in order to enlarge the image on the electrode (hereinafter, referred to as reducing electrode) 25 side, a convex optical lens 23 is arranged on the reducing electrode 25. On the other hand, the flat glass 22 is arranged on the electrode 24 in the other portion that is not reduced. On the other hand, the backlight units 26a and 26b for illuminating the two display panels 20a and 20b, respectively, can be designed to provide brighter light on the reduction electrode 25 side.

However, in the case of the conventional display device shown in FIG. 2, since a separate optical lens is required, the manufacturing time and cost increase due to the increase in the total number of parts. Further, if the curvature of the optical lens is not designed very precisely, the image may be distorted due to the influence of aberration or the like. Further, in order to elaborately design an optical lens, the manufacturing cost has to be greatly increased. It is also difficult to design the backlight unit to provide brighter light to a particular area, which at an additional cost. Further, as a backlight unit, it is almost difficult to precisely control the brightness in a specific region.

<p> An object of the present invention is to use a simpler and lower cost method than before so that no additional components are required and the joint between two or more interconnected display panels is not visible. It is to provide a foldable display device.</p>

<p> According to the present invention, in a display device in which a plurality of display panels are interconnected to display one image, the pixels on the junction side of each display panel with other display panels are smaller in size than the other pixels. The pixel on the joint portion side of each display panel is characterized in that the brightness is higher than that of the other pixels.</p><p> According to one embodiment of the present invention, the junction-side pixels of the display panel independently serve as one pixel.</p><p> Further, when one pixel line obtained by extending the corresponding two pixel lines of two display panels adjacent to each other is divided into continuous areas having the same width, one pixel may be arranged in each area.</p><p> Further, the size of the pixels can be gradually increased from the joint portion side of the display panel toward the central portion over at least two pixel rows.</p><p> In this case, the luminous intensity emitted from each pixel of the display panel is the same.</p><p> On the other hand, according to another embodiment of the present invention, the corresponding two pixels on both sides of the junction between two adjacent display panels can jointly serve as one pixel.</p><p> Further, when one pixel line extending from the corresponding two pixel lines of two adjacent display panels is divided into continuous regions having the same width, the two pixels on both sides of the joint portion are contained in one region. They are arranged together and the remaining pixels can be arranged one by one in one area.</p><p> In this case, the sum of the luminosities emitted from the two pixels on both sides of the joint is the same as the luminosities emitted from the other pixel.</p><p> According to the present invention, the display panel is a self-luminous display panel.</p><p> For example, the display panel may be any of an organic light emitting element (OLED: Organic Electroluminescent Light Emitting Device), an electroluminescent element (FED: Field Emission Display), a plasma display panel (PDP: Plasma Display Panel), and an inorganic EL (Electroluminsecence). Can be one.</p><p> Further, according to the present invention, the joint portion between the two displays can be provided with a hinge member so that the two display panels adjacent to each other are mutually folded.</p><p> Further, it is appropriate that the distance between the two pixels on both sides of the joint between the two display panels adjacent to each other is within the range of 0.1 mm to 1 mm.</p><p> On the other hand, it is desirable that the pixels representing the colors of red (R), green (G), and blue (B) are repeatedly arranged along the joint.</p>

<p> According to the present invention, in a display device in which a plurality of display panels are joined to each other to display one image, the joint between two adjacent display panels can be made invisible by a simple method. That is, unlike the conventional case, a separate optical lens is not required. Further, since the display device according to the present invention uses a self-luminous display panel, it is easy to control the brightness of a specific pixel to a desired size. Therefore, the reduction in pixel size can be easily compensated, and the backlight unit does not need to be complicatedly redesigned. Further, according to the present invention, the size of the junction between the two display devices can be reduced, so that the distance between the corresponding two pixels on both sides of the junction can be reduced. Therefore, as compared with the conventional case, the discontinuity of the image due to the joint portion hardly appears.</p>

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

FIG. 3 is a drawing showing a pixel configuration for making seams invisible in a display device according to an embodiment of the present invention in which a plurality of display panels are interconnected to display one image.

As shown in FIG. 3, the display device according to the embodiment of the present invention includes a plurality of interconnected display panels 30a and 30b. In FIG. 3, only two display panels 30a and 30b are exemplified. However, it is also possible to additionally join more display panels, and even in this case, the principles according to the present invention can be applied in the same manner. According to a good embodiment of the present invention, among the pixels arranged in a matrix on each display panel 30a, 30b, the pixels 34a, 34b adjacent to the junction 31 side between the two display panels 30a, 30b are The size is smaller than the other pixels 33a and 33b. Then, the pixels 34a and 34b on the joint portion 31 side are controlled to have higher brightness than the other pixels 33a and 33b, thereby compensating for the decrease in size. Further, in the drawing of FIG. 3, when the pixels representing the colors of red (R), green (G), and blue (B) are repeatedly arranged in the horizontal direction, only the pixels of a specific color can be reduced. In order to prevent this, it is desirable that the pixels representing the RGB colors are repeatedly arranged along the direction of the junction 31, that is, in FIG. 3, along the vertical direction.

The joint 31 can also be formed from an adhesive material that simply joins the two display panels 30a, 30b. However, for example, a hinge member can be used to design two display panels 30a and 30b that are adjacent to each other so that they can be folded into each other. In this case, the display device according to the present invention can be used as a portable foldable display device in which two display panels can be folded and carried.

According to a preferred embodiment of the present invention, the display panels 30a and 30b are self-luminous display panels that do not use a backlight unit. For example, a PLED, FED, PDP or inorganic EL element can be used as the display panel. According to the present invention, since the self-luminous display panel is used as the display panels 30a and 30b, it is easily desired to obtain the brightness of only a specific pixel by simply extending the duration of the applied voltage or increasing the size. Can be improved accurately to the extent of.

On the other hand, as shown in FIG. 3, by reducing the size of the pixels 34a, 34b adjacent to the junction 31 side between the two display panels 30a, 30b, the junction side of the two display panels 30a, 30b The distance between pixels 34a and 34b can be reduced. As shown in FIG. 4A, in the edge structure of the display panel when pixels of general length are used, the junction 31 of FIG. 3 must be formed on the outside of the partition wall 36 to protect the pixels 33. .. Here, the distance between the pixel 33 and the partition wall 36, the thickness of the partition wall 36, and the structure and thickness of the joint portion 31 determine the distance between the pixels 34a and 34b on both sides of the joint portion 31. As shown in FIG. 4B, when the pixels on the edge side of the display panel are shortened, the shorter the pixels, the shorter the distance between the pixels 34 and the partition wall 36 can be. Further, according to the present invention, it is possible to reduce the overall thickness of the partition wall 36 and the joint portion 31 by integrally forming the partition wall 36 and the joint portion 31.

In this case, the distance between the pixels 34a, 34b on the joint side of the two display panels 30a, 30b can be in the range of, for example, about 0.1 mm to 1 mm. Generally, when the distance between two points is 0.1 mm, the two points appear to be one point at a distance of 40 cm or more. Therefore, if the distance between the pixels 34a and 34b on the junction side is within the range of about 0.1 mm to 1 mm, black stripes are hardly visible between the images displayed on the two display panels 30a and 30b, respectively.

5A and 5B are display devices according to the present invention, in which black stripes are further hidden between two display panels 30a and 30b, and two images displayed on the two display panels 30a and 30b are mutually displayed. The arrangement of pixels for natural connection is shown.

First, in the case of FIG. 5A, the corresponding two pixels 34a and 34b on both sides of the joint portion 31 of the two display panels 30a and 30b jointly play the role of one pixel. That is, the two pixels 34a and 34b on both sides of the joint portion 31 are controlled so as to always display the same image data. At this time, as shown in FIG. 5A, when one pixel line obtained by extending the corresponding two pixel lines of two display panels 30a and 30b adjacent to each other is divided into continuous regions A having the same width, the joint portion The two pixels 34a and 34b on both sides of 31 are arranged together in one area, and the remaining pixels 33a and 33b are arranged one by one in one area. In this case, the sum of the total luminosity emitted from the two pixels 34a, 34b on both sides of the joint portion 31 is controlled to be the same as the total luminous intensity emitted from the other one pixel 33a, 33b. For example, if the sum of the areas of the two pixels 34a and 34b on both sides of the junction 31 is 2/3 of the area of the other pixel, the brightness of the two pixels 34a and 34b is 3 of the brightness of the other pixels, respectively. / It is controlled to be doubled. By doing so, since the pixels of the two display panels 30a and 30b appear to be continuously arranged at the same interval, the occurrence of black stripes by the joint portion 31 is minimized, and the images on both sides of the joint portion 31 are imaged. Can be connected naturally.

Further, in the case of FIG. 5B, the corresponding two pixels 34a and 34b on both sides of the joint portion 31 of the two display panels 30a and 30b each play the role of one pixel independently. That is, the two pixels 34a and 34b on both sides of the joint portion 31 are controlled so as to display image data independently. At this time, as shown in FIG. 5B, when one pixel line obtained by extending the corresponding two pixel lines of the two display panels 30a and 30b adjacent to each other is divided into continuous regions A having the same width, one One pixel is arranged for each area A. Therefore, the pixels 34a and 34b on both sides of the joint portion 31 having a size smaller than the other pixels 33a and 33b are also arranged one by one in one region A like the other pixels 33a and 33b. In this case, the luminous intensity emitted from one pixel 34a, 34b on the junction 31 side of the display panels 30a, 30b is controlled to be the same as the luminous intensity emitted from the other pixels 33a, 33b. For example, if the area of one pixel 34a, 34b adjacent to the junction 31 is 1/2 of the area of the other pixel, the brightness of the pixels 34a, 34b is twice the brightness of the other pixel. Is controlled. By doing so, since the pixels of the two display panels 30a and 30b appear to be continuously arranged at the same interval, the occurrence of black stripes by the joint portion 31 is minimized, and the images on both sides of the joint portion 31 are imaged. Can be connected naturally.

On the other hand, in the above-described embodiment, only the sizes of the pixels 34a and 34b adjacent to the joint portion 31 are reduced. However, as in the embodiment shown in FIG. 6, pixels 34a', 34a'', 34a''', 34b', 34b' span a plurality of rows from the junction 31 of the display panels 30a, 30b toward the center. It is also possible to gradually increase the size of', 34b'''. Also in this case, as shown in FIG. 5B, all the pixels can independently play the role of one pixel regardless of the pixel size. Also, when one pixel line that extends the corresponding two pixel lines of two adjacent display panels 30a and 30b is divided into continuous areas A of the same width, pixels are generated for each area A regardless of size. Each can be placed one by one. The luminous intensity emitted from each pixel is also controlled to be constant in all pixels regardless of the size.

The present invention has been described with reference to the embodiments shown in the drawings, which are merely exemplary, and those skilled in the art will appreciate a variety of modifications and equivalent other embodiments. You will see that. Therefore, the true technical protection scope of the present invention must be determined by the technical idea of the claims.

The present invention is applicable to technical fields related to portable display devices such as mobile phones and PMPs.

<figref num="1">It is a drawing which briefly shows the concept of a general foldable display device.</figref><figref num="2">FIG. 5 is a drawing showing a conventional structure for making a seam invisible in a foldable display device.</figref><figref num="3">FIG. 5 is a drawing showing a pixel configuration for making a seam invisible in a foldable display device according to an embodiment of the present invention.</figref><figref num="4A">It is a drawing which shows the edge structure of the display panel when the pixel of a general length is used.</figref><figref num="4B">It is a drawing which shows the edge structure of a display panel when a pixel with a short length is used.</figref><figref num="5A">It is a drawing which shows the pixel arrangement in the foldable display apparatus by this invention.</figref><figref num="5B">It is a drawing which shows the pixel arrangement in the foldable display apparatus by this invention.</figref><figref num="6">FIG. 5 is a drawing showing a pixel configuration for making seams invisible in a foldable display device according to another embodiment of the present invention.</figref>

Code description

30a, 30b display panel, 31 junctions, 33a, 33b, 34a, 34b pixels.