Color filter board and display device

Abstract

To provide a color filter board capable of easily changing dimensions of a white sub-pixel without affecting an area ratio of an RGB sub-pixel.SOLUTION: In a color filter board in which multiple pixel regions Px are formed, the pixel regions are divided into multiple sub-regions by a black matrix Bm. The multiple sub-regions include a polygonal center region 51 functioning as a white sub-pixel, and multiple polygonal peripheral regions 52, 53, 54, 55, 56, 57 positioned around the center region. The peripheral regions have at least each one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel. The center of the pixel regions matches the center of the center region. The black matrix for dividing an adjacent peripheral region extends from the contour of the pixel regions to the center of the pixel regions. Angles of the center region and all the peripheral regions are equal to the number of integer multiples of 30.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a color filter substrate and a display device including the color filter substrate. [Background technology]

[0002] A known color filter for use in a display device is one in which one pixel is composed of four subpixels: red, green, and blue colored subpixels and a white subpixel. This type of color filter is also called an RGBW color filter, using the initial letters of the respective colors.

[0003] Regarding RGBW color filters, Patent Document 1 discloses a layout in which subpixels of four colors, R (red), G (green), B (blue), and W (white), are arranged in two rows and two columns. Each subpixel is square, and a pixel made up of four subpixels is also square. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-129504 A Summary of the Invention [Problem to be solved by the invention]

[0005] In an RGBW color filter, the W subpixel affects the brightness of the screen, so there may be a demand to adjust the size of the W subpixel to achieve a desired brightness. However, when the W subpixel is changed in the configuration described in Patent Document 1, the size changes of the remaining three subpixels tend to be non-uniform. Therefore, even if the desired brightness is achieved, there is a possibility that the color development (color reproducibility) will be adversely affected. Furthermore, in display devices, the size of a pixel is typically determined based on the screen dimensions, resolution, etc., so it is typically not possible to change the shape or size of a pixel in order to keep the ratio of the remaining three sub-pixels constant.

[0006] In view of the above circumstances, an object of the present invention is to provide a color filter substrate that allows the size of a white sub-pixel to be easily changed without affecting the area ratio of RGB sub-pixels. [Means for solving the problem]

[0007] A first aspect of the present invention is a color filter substrate having a plurality of pixel regions defined by a black matrix formed on a substrate. The pixel area is divided into a plurality of sub-areas by the black matrix. The plurality of sub-regions includes a polygonal center region that functions as a white sub-pixel, and a plurality of polygonal peripheral regions positioned around the center region. The peripheral region has at least one red subpixel with a red filter, one green subpixel with a green filter, and one blue subpixel with a blue filter. The center of the pixel region and the center of the central region coincide with each other, and the black matrix that separates the adjacent peripheral regions extends from the outline of the pixel region toward the center of the pixel region. The angles of the corners of the center region and all of the peripheral regions are integer multiples of 30.

[0008] A second aspect of the present invention is a display device including the color filter substrate according to the first aspect and a light source that emits light toward the color filter substrate. Effect of the Invention

[0009] The color filter substrate according to the present invention makes it easy to change the size of the white sub-pixel without affecting the area ratio of the RGB sub-pixels. [Brief description of the drawings]

[0010] [Figure 1] 1 is a partial plan view showing a color filter substrate according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of the color filter substrate. [Diagram 3] FIG. 2 is an enlarged plan view showing a pixel region of the color filter substrate. [Figure 4] FIG. 2A is a partial plan view showing a process during the manufacture of the color filter substrate, and FIG. 2B is a cross-sectional view of the substrate during the process. [Diagram 5] 13(a) and 13(b) are diagrams showing examples of pixel regions having center regions with different areas. [Figure 6] FIG. 4 is a cross-sectional view showing another example of the color filter substrate. [Figure 7] 1 is a cross-sectional view showing an example of a display device to which the color filter substrate is applied. [Figure 8] 1 is a cross-sectional view showing an example of a display device to which the color filter substrate is applied. [Figure 9] 1 is a cross-sectional view showing an example of a display device to which the color filter substrate is applied. [Figure 10] FIG. 4 is an enlarged plan view showing a pixel region of a color filter substrate according to a second embodiment of the present invention. [Figure 11] 13(a) and 13(b) are enlarged plan views showing pixel regions of a color filter substrate according to a modified example of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A first embodiment of the present invention will be described with reference to FIGS. Fig. 1 is a partial plan view showing a color filter substrate 1 according to this embodiment, and Fig. 2 is a cross-sectional view of the color filter substrate 1. The color filter substrate 1 includes a substrate 10, a black matrix Bm formed on the substrate 10, and four types of color filters: a red filter R, a green filter G, a blue filter B, and a white filter W.

[0012] The color filter substrate 1 has a plurality of pixel regions. The pixel regions Px according to this embodiment have a regular hexagonal outer shape and are arranged in a honeycomb pattern without gaps on the substrate 10. Each pixel region Px is partitioned from adjacent pixel regions by a black matrix Bm.

[0013] 3 is an enlarged plan view of one pixel region Px. The pixel region Px according to this embodiment is divided into seven sub-regions by a black matrix Bm. The sub-regions are made up of a central region 51 that is a polygon located in the center, and six peripheral polygonal regions 52 , 53 , 54 , 55 , 56 , and 57 that are located around the central region 51 .

[0014] The outer shape of the center region 51 is a regular hexagon that is smaller than the pixel region Px. The center of the pixel region Px and the center of the center region 51 coincide with each other, and the phases of the six corners are also the same. The area around the center region 51 is divided into six peripheral regions 52 to 57, which are congruent isosceles trapezoids, by a partition matrix Pm that constitutes part of the black matrix. The partition matrix Pm according to this embodiment is a straight line connecting the vertices of the pixel region Px and the corners of the center region 51 in the same phase. That is, each partition matrix Pm extends from the black matrix that forms the outline of the pixel region Px toward the center of the pixel region Px, and the center of the pixel region Px and the center of the center region 51 are located at the position where the extension lines intersect.

[0015] A white filter W is disposed in the center region 51. Two red filters R, two green filters G, and two blue filters B are disposed in each of the six peripheral regions 52, 53, 54, 55, 56, and 57. Although Fig. 1 and Fig. 3 show an example in which the three color filters are disposed in order around the center of the pixel region, this is not essential. Therefore, two of each of the three color filters may be disposed side by side, or only one or two of the three may be disposed side by side. The peripheral region in which the red filters R are arranged functions as red subpixels, the peripheral region in which the green filters G are arranged functions as green subpixels, and the peripheral region in which the blue filters B are arranged functions as blue subpixels.

[0016] An example of a manufacturing procedure for the color filter substrate 1 will be described. First, prepare the substrate 10. The substrate 10 is a light-transmitting member, and is typically made of transparent resin or glass.

[0017] 4(a) and 4(b), a black matrix Bm corresponding to Px in all pixel regions including the partition matrix Pm is formed on the first surface 10a of the substrate 10. The black matrix Bm can be formed by a known technique such as photolithography. 4(a) and (b) are shown at different magnifications to make the structure easier to understand, and as a result, the dimensions of the black matrix Bm are different between (a) and (b).

[0018] Next, color filters corresponding to each sub-region partitioned by the black matrix Bm are arranged. The color filters can be formed by known techniques, such as applying a filter material by printing and patterning it using photolithography. Each color filter is formed so as to fill each sub-region without gaps and to overlap a part of the black matrix. Therefore, depending on the order of forming the color filters, the overlapping order of the color filters on the black matrix varies in various ways. However, when the color filter substrate 1 is viewed from the second surface 10b side of the substrate 10, this overlapping part is hidden by the black matrix Bm and cannot be seen, so it does not affect the performance of the color filter substrate 1. Therefore, there is no particular restriction on the order of forming the color filters, and it can be determined appropriately. When all the color filters are arranged and cured, the color filter substrate 1 according to this embodiment is completed.

[0019] The effects of the color filter substrate 1 according to this embodiment will be described. In the color filter substrate 1, the center region 51 in which the white filter W is arranged affects the luminance of each pixel region Px and, ultimately, the brightness of the entire display screen. Therefore, by increasing or decreasing the area of ​​the center region, the luminance of the pixel region Px can be adjusted to a desired value within a certain range.

[0020] 5(a) and 5(b) show pixel regions Px1 and Px2 in which the area of ​​center region 51 has been reduced and increased, respectively, with respect to FIG. 4. Center regions 51a and 51b of pixel regions Px1 and Px2 maintain the same regular hexagonal shape as center region 51, but only the size is changed. As a result, peripheral regions 52a to 57a of pixel region Px1 and peripheral regions 52b to 57b of pixel region Px2 all maintain a mutually congruent trapezoidal shape, but only the areas are increased or decreased relative to peripheral regions 52 to 57 of pixel region Px. That is, the area ratio of the red filters R, green filters G, and blue filters B is the same and unchanged between the pixel region Px shown in FIG. 3 and the pixel regions Px1 and Px2 shown in FIG.

[0021] In this way, in the color filter substrate 1 according to this embodiment, the area of ​​the center region 51 functioning as a white subpixel can be easily increased or decreased by changing the layout of the subregions in the pixel region without changing the area ratio of the color filter region. As a result, the color filter substrate 1 can be easily applied to display devices with various specifications and has extremely high versatility.

[0022] The color filter substrate according to this embodiment can be applied to various display devices. When each sub-region is controlled by liquid crystal, a configuration like that of a color filter substrate 1A shown in Fig. 6 is suitable. In the color filter substrate 1A, a black matrix Bm and color filters formed on a substrate 10 are covered with a transparent planarization layer 20. Furthermore, partition walls 30 are formed on the planarization layer 20. The partition walls 30 are formed so as to overlap with the black matrix Bm in a plan view of the color filter substrate 1A, and divide the planarization layer 20 into regions corresponding to each sub-region.

[0023] 7 shows a display device 100 to which the color filter substrate 1A is applied. In the display device 100, a liquid crystal layer 111 is disposed in a space partitioned by partition walls 30. In the display device 100, light from a fluorescent tube 120, which is a light source, passes through a liquid crystal layer 111 controlled by a driving substrate 112, enters the color filter substrate 1A, and is then emitted from the screen. This allows the on / off and brightness of the light in each sub-region to be adjusted, enabling a desired display.

[0024] 8 uses a plurality of white LEDs (light emitting diodes) 121 as a light source instead of fluorescent tubes 120. The operation of display device 101 is generally similar to that of display device 100, except for the difference in the light source. The light source is not limited to the above-mentioned fluorescent tube and white LED. For example, a light source in which a blue LED or a purple LED is appropriately combined with a resin mold containing a fluorescent material or an ND (Natural Density) filter to provide three light sources, a red light source, a green light source, and a blue light source, and further combined with a diffusion plate, can be used.

[0025] 9 is an example of a display device that does not use liquid crystal. The color filter substrate 1B used has the same structure as the color filter substrate 1A, except that it does not have the partition walls 30. The substrate on the light source side is provided with partition walls 130 corresponding to each sub-region, and white LEDs 121 are arranged in each of the regions defined by the partition walls 130. In the display device 102, the white LEDs 121 in each region are independently controlled, thereby enabling a desired display without using a liquid crystal layer. As the white LEDs used in the display device 102, minute LEDs also known as micro LEDs are suitable.

[0026] As described above, the color filter substrate of this embodiment has excellent properties in that it can be suitably applied to display devices of various configurations, and that layout changes for adjusting the area of ​​the white subpixel in accordance with various specifications including the type of light source can be easily performed without affecting the area ratios of the other color filters.

[0027] A second embodiment of the present invention will be described with reference to Fig. 10. In the following description, configurations common to those already described will be given the same reference numerals and duplicated description will be omitted.

[0028] FIG. 10 is an enlarged plan view showing a pixel region PxA of the color filter substrate of the present embodiment. The pixel region PxA has a configuration generally similar to that of the pixel region Px according to the first embodiment, but is different in that the center region 51c is a hexagon whose center coincides with that of the pixel region PxA, but is rotated by 30° with respect to the pixel region PxA. Since each partition matrix Pm extends toward the center of the pixel region PxA as in the first embodiment, the partition matrix Pm is connected to the vicinity of the midpoint of each side of the black matrix Bm, which is a hexagon in a plan view and divides the center region 51c.

[0029] In this embodiment, the peripheral regions 52c to 57c are not trapezoidal but are pentagonal with reflex angles of 240° corresponding to the corners of the center region 51c, but the shapes are generally congruent.

[0030] In this embodiment, the luminance of the pixel region Px can be adjusted to a desired value without changing the area ratio of the color filters by changing the size of the center region 51c while maintaining the center position, thus providing substantially the same effects as the first embodiment. The color filter substrate according to this embodiment can be produced in a manner generally similar to that of the first embodiment, except that the shape of the black matrix formed on the first surface of the substrate 10 is changed.

[0031] Although each embodiment of the present invention has been described above, the specific configuration is not limited to this embodiment, and configuration changes and combinations that do not depart from the gist of the present invention are also included.

[0032] For example, the shape of the pixel region in a plan view is not limited to the regular hexagon described above. Fig. 11 shows examples of pixel regions having different shapes in a plan view.

[0033] 11(a), a pixel region Px3 of a modified example has an equilateral triangular shape in a plan view. An equilateral triangular center region 61 is disposed in the center of the pixel region Px3, and red filters R, green filters G, and blue filters B are disposed in three peripheral regions 62, 63, and 64 around the center region 61, respectively.

[0034] A pixel region Px4 of a modified example shown in FIG. 11(b) also has a regular triangular shape in a plan view, but has a regular hexagonal center region 51c disposed in the center.

[0035] Similar to the above-described embodiments, the color filter substrate having the pixel region shown in FIG. 11 also has the excellent characteristic that the luminance of the pixel region Px can be adjusted to a desired value without changing the area ratio of each color filter. In addition, in the pixel region having a hexagonal shape in plan view shown in the embodiment, the center region may be an equilateral triangle. In all of the above-mentioned embodiments and modifications, the angles of the corners in the center region and all of the sub-regions are integer multiples of 30, such as 30°, 60°, 120°, 150°, and 240°.

[0036] The pixel regions of the regular hexagon shown in the embodiment and the equilateral triangle and square shown in the modified example are advantageous in that they can be easily arranged without gaps in the display area, but the pixel regions according to the present invention can also be of other shapes. In this case, the pixel regions can be made to have an outer shape that makes it easy to arrange them without gaps by, for example, changing the shape of a part of the black matrix.

[0037] In the above example, a white filter is disposed in the center region, but this is not essential to the present invention. For example, when the present invention is applied to a display device in which the light source emits white light, the center region may transmit the light from the light source as it is without disposing a white filter.

[0038] In the present invention, the "pixel region" means a region that can function as one pixel by itself, and is not necessarily treated as one pixel in the display device to which it is applied. For example, in an embodiment having a pixel region of an equilateral triangle in plan view as shown in Fig. 11, the display device can treat two adjacent pixel regions as one pixel, thereby making it possible to make all pixels have the same shape and orientation, and stabilizing the display quality. [Explanation of symbols]

[0039] 1, 1A, 1B Color filter substrate 10 Substrate 51, 51a, 51b, 51c, 61 Center area 52, 53, 54, 55, 56, 57, 62, 63, 64 Surrounding Areas 100, 101, 102 display device 120 Fluorescent tube (light source) 121 White LED (light source) B Blue filter Bm Black Matrix G Green filter Px, Px1, Px2, Px3, Px4, PxA pixel area R Red filter W White Filter

Claims

1. A color filter substrate having a plurality of pixel regions formed on a substrate, the pixel regions being partitioned by a black matrix, The pixel region is divided into a plurality of sub-regions by the black matrix, The plurality of sub-regions include: a center region of the polygon that functions as a white subpixel; a plurality of polygonal peripheral regions located around the central region; the peripheral region includes at least one red subpixel having a red filter, at least one green subpixel having a green filter, and at least one blue subpixel having a blue filter; The center of the pixel region and the center of the center region are aligned with each other, the black matrix that divides the adjacent peripheral regions extends from the outline of the pixel region toward the center of the pixel region, The angles of the corners of the center region and all of the peripheral regions are an integer multiple of 30. Color filter substrate.

2. the pixel region and the center region have the same polygonal shape; The color filter substrate according to claim 1 .

3. The phase of the outline of the pixel region and the phase of the outline of the center region are the same. The color filter substrate according to claim 2 .

4. The peripheral regions are all the same polygon. The color filter substrate according to claim 1 .

5. The pixel region has an outer shape of a regular hexagon or a regular triangle. The color filter substrate according to claim 1 .

6. A color filter substrate according to claim 1 , a light source that emits light toward the color filter substrate; Equipped with Display device.

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