JP2002107709A - Color liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the opening ratio, reflectance and transmittance, to improve the luminance, to enhance the contrast and thereby, to improve the total display performance. SOLUTION: In a color liquid crystal display device 15 to be used in a reflection mode, a reflection film 17a, color filter 18, protective film 20, transparent electrode 21 and alignment film 23 are successively formed on a transparent substrate 16. In the color filter 18, three color layers of red(R), green(G) and blue(B) form one pixel 28, and each pixel 28 is surrounded by a light shielding film 19 to form a lattice form. The pixel groups are arranged in such a manner that the vertical lines are aligned into the respective color layers of red(R), green(G) and blue(B) and that the lateral lines shows the sequence of red(R), green(G) and blue(B) which are repeated. In each pixel group, no light shielding film 19 is formed in the gap between the red(R) and green(G) or the gap between the green(G) and blue(B).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color liquid crystal display device having a color filter in which pixels each having a different color layer arranged individually on a substrate are arranged in a matrix, and colorized by the color filter. Things.

[0002]

2. Description of the Related Art A conventional color liquid crystal display device having a color filter will be described with reference to FIGS.
No. 90342).

FIG. 6 is a schematic sectional view of a color liquid crystal display device 1, and FIG. 7 is a schematic plan view of a color filter.

The color liquid crystal display device 1 will be described as a reflection type simple matrix type color liquid crystal display device or as a transflective type simple matrix type color liquid crystal display device.

[0005] Reference numerals 2 and 9 denote transparent substrates such as glass substrates. A reflective film 3a having light reflectivity is formed on one of the transparent substrates 2, or both have a light transmittance and a light reflectivity. The semi-permeable film 3b is provided.

When the reflection film 3a is used, a reflection type color liquid crystal display device is obtained, and when the semi-transmission film 3b is used, a semi-transmission type color liquid crystal display device is obtained.

Then, the reflection film 3a or the semi-transmission film 3b
A color filter 4 consisting of three colors is formed by applying a colored layer of, for example, red (R), green (G), or blue (B) thereon.

In the color filter 4, FIG.
As shown in (1), the colored layers are arranged in a matrix, and a light-shielding film 5 made of a black resin or a light-shielding metal is provided between the individual colored layers.

In practice, a light-shielding film 5 is formed in advance on the reflection film 3a or the semi-transmissive film 3b of the transparent substrate 2 in order to provide a lattice-shaped opening 14, and each colored layer is formed in the opening 14 with red ( R) → green (G) → blue (B).

Next, the color filter 4 and the light shielding film 5
In order to protect the protective film 6, a protective film 6 made of a silica material or a synthetic resin is provided, and a transparent conductive film (for example, IT
A transparent electrode 7 made of O) is formed in a stripe shape, and subsequently, an alignment film 8 for aligning liquid crystal is formed.

On the other transparent substrate 9, a transparent electrode 10 made of a transparent conductive film (for example, ITO) is formed in a stripe shape, and an alignment film 11 is formed thereon.

The two transparent substrates 2 and 9 are opposed to each other so that the transparent electrodes 7 and 10 are orthogonal to each other and the orthogonal portions are arranged in a matrix.

At this time, a spherical spacer 13 is provided to provide a predetermined space between the transparent substrates 2 and 9, and the liquid crystal 12 is filled and sealed. This enclosure is sealed with a sealant.

[0014]

As described above, in the color liquid crystal display device 1 having the above structure, two transparent substrates 2 and
When the spacer 13 and the liquid crystal 12 are interposed between the transparent substrates 2 and 9, the two transparent substrates 2 and 9 are bonded to each other via a sealant. And the opening 14 of the light-shielding film 5.

Therefore, the width of the light-shielding film 5 is set large in advance so as not to cause this shift, thereby eliminating the bonding error of the substrates. However, on the other hand, the area of the light-shielding film 5 becomes large. The aperture ratio decreases.

With respect to a reflection type color liquid crystal display device,
As the aperture ratio is reduced, the reflectance is reduced and the luminance is reduced. Therefore, a liquid crystal display device without the light-shielding film 5 for increasing the aperture ratio to solve the problem is proposed.

However, in a reflective type color liquid crystal display device in which the light-shielding film 5 is not provided, since the voltage is also applied to the periphery of the electrode to which the voltage is applied, the liquid crystal in the portion between the electrodes becomes unstable and the contrast is reduced. I was

[0018] Even in a transflective color liquid crystal display device, there is a problem similar to that of such a reflection type color liquid crystal display device when used in a reflection mode.

When the transflective color liquid crystal display device is used in the transmission mode, a backlight is provided on the back surface of the glass substrate 2 in the color liquid crystal display device 1 shown in FIG. Although the light is passed through the substrate 2 and further through the semi-transmissive film 3b, the presence of the light-shielding film 5 lowers the aperture ratio and at the same time lowers the transmittance.
This reduced the brightness and darkened the display. On the other hand, when the light shielding film 5 was not provided, the contrast was reduced.

Accordingly, the present invention has been devised in view of the above circumstances, and an object of the present invention is to increase the aperture ratio in a reflective color liquid crystal display device or a transflective color liquid crystal display device in a reflective mode. It is another object of the present invention to provide a color liquid crystal display device in which the reflectivity is increased, the luminance is improved, and the contrast is also increased.

Another object of the present invention is to provide a transflective color liquid crystal display device in a transmissive mode in which the aperture ratio is increased, the transmissivity is increased, the luminance is improved, and the contrast is also increased. It is an object of the present invention to provide a color liquid crystal display device in which the display quality is well balanced by enhancing the performance comprehensively.

[0022]

In the color liquid crystal display device of the present invention, pixels formed by individually arranging different colored layers on a substrate are arranged in a matrix, and only pixels between the pixels of the matrix pixel group are arranged. A light-shielding film is provided on the substrate, and a plurality of transparent electrodes are arranged in a stripe pattern on a matrix-like pixel group. A twisted nematic liquid crystal is formed on the other substrate in which the other transparent electrode group and the alignment film, which are arranged in a stripe pattern, are sequentially laminated so that both the transparent electrodes of the one transparent electrode group and the other transparent electrode group are orthogonal to each other. It is characterized by being arranged via.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A color liquid crystal display device of the present invention will be described with reference to FIGS. FIG. 1 shows a color liquid crystal display device 1
5 is a schematic cross-sectional view of FIG. 5, and FIG. 2 to FIG. 5 show arrangement patterns of colored layers of a color filter.

(Example 1) A color liquid crystal display device 1 shown in FIG.
Reference numeral 5 denotes a structure applied to a reflection type or a semi-transmission type.

Reference numeral 16 denotes a transparent substrate made of a glass substrate or the like, which is one of the substrates, on which a reflective film 17a or a semi-transmissive film 17b is provided.

When the reflection film 17a is provided, Al, C
r with a metal film of 300 mm or more,
For example, the reflective color liquid crystal display device 15 has a thickness of 800 mm.

When the semi-permeable film 17b is provided, Al,
A metal film made of Ag, Ti (TiOx), an Al alloy, an Ag alloy, or a dielectric film of a low refractive index layer and a high refractive index layer has a thickness of 200 to 300 (or more).
To form a transflective color liquid crystal display device 15.

The reflection film 17a or the semi-transmission film 17
On b, for example, three of red (R), green (G), and blue (B)
The color filters 18 of three colors are formed by applying the respective colored layers. Further, a light-shielding film 19 made of black resin or light-shielding metal is provided at a predetermined portion between the colored layers.

On the color filter 18 and the light shielding film 19,
To protect them, a protective film 20 made of a silica material, a synthetic resin, or the like is provided, and a transparent electrode 21 made of a transparent conductive film (for example, ITO) is formed thereon in a stripe shape to form the one-side transparent electrode group. Then, an alignment film 23 made of a polyimide resin or the like is formed thereon.

On the other hand, on the transparent substrate 24, a transparent electrode 25 made of a transparent conductive film (for example, ITO) is formed in a stripe shape to form the other transparent electrode group, and an orientation made of a polyimide resin or the like is formed thereon. A film 26 is formed.

Then, the transparent substrate 16 and the transparent substrate 24 are opposed to each other so that the transparent electrode 21 and the transparent electrode 24 are orthogonal to each other, and the orthogonal portions are arranged in a matrix.
Make them face each other. At this time, a spherical spacer 27 is provided to provide a predetermined space between the transparent substrates 16 and 24, and the liquid crystal 22 is filled and sealed. This enclosure is sealed with a sealant.

In this embodiment, each pixel 28 is formed of three colored layers of red (R), green (G), and blue (B) as one pixel 28 as in a color filter 18 shown in FIG. By surrounding it with 19, it has a lattice shape.

The columns in the figure are aligned with the respective colored layers of red (R), green (G), and blue (B).

In the row, pixels arranged in the order of red (R) → green (G) → blue (B) are arranged, and then the pixels arranged in that order are repeatedly arranged. At this time, for each pixel group, the light shielding film 19 is not formed in the gap between red (R) and green (G) and the gap between green (G) and blue (B).

By not forming the light shielding film 19 in this manner, the aperture ratio per pixel 28 is increased.

For example, a 10.4 inch type 800 × 6
In the 00 (SVGA) reflective and transflective color liquid crystal display device 15, the pixel pitch is 264 μm and the width of the light shielding film 19 is 20 μm. A gap having a width of 10 μm is formed between the red (R) and green (G) and between the green (G) and the blue (B) of the colored layer where the light shielding film 19 is not formed.

In this configuration, the aperture ratio per pixel ｛opening area ÷ (color filter pitch × pixel pitch)
× 100｝ is (224 × 244) / (264 × 264) × 100 = 7
It is 8.4%.

The aperture ratio differs depending on each colored layer.

Red (R) and blue (B) are (73 × 244) / (88 × 264) × 100 = 76.
6%, and for green (G), (78 × 244) / (88 × 264) × 100 = 81.
9%, and the average of these three colors is 78.4%. The light-shielding portion in one pixel is narrowed, and a large amount of light is projected on the reflection film 17a, so that the reflectance is also substantially proportional to the aperture ratio, and the reflectance in the case of a reflective color liquid crystal display device is 1
1.8%.

The light-shielding film 19 has a line width of, for example, 10 μm.
m and the gap between the red (R) and green (G) and the gap between the green (G) and blue (B) of the colored layer are each reduced to 10 μm. Determined by

The aperture ratios of red (R) and blue (B) are (78 × 254) / (88 × 264) × 100 = 85.
2%, and for green (G), (83 × 254) / (88 × 264) × 100 = 90.
7%, or 87.0% on average. The reflectance is 13.1% per pixel.

Thus, in the use of the reflective color liquid crystal display device 15 or the transflective color liquid crystal display device 15 of the present invention in the reflection mode, the reflectance is increased and the luminance is improved by increasing the aperture ratio. I was able to. Moreover, the light-shielding film is surrounded by each pixel unit, whereby the factor of instability of the liquid crystal due to the voltage applied to the adjacent pixel is reduced or eliminated, and as a result, the contrast is improved.

Also in the transmissive mode of the transflective color liquid crystal display device 15 of the present invention, the transmissivity was increased and the luminance was improved by increasing the aperture ratio. Moreover, since the light-shielding film is surrounded by each pixel unit, the cause of the instability of the liquid crystal due to the voltage applied to the adjacent pixel is reduced or eliminated.
Improved contrast.

Comparative Example Next, a comparative example will be described. 10.4 inch 800 × 600 (SVG
In the color liquid crystal display device of the reflection type or the transflective type A), the above-mentioned color filter 18 is changed to the conventional color filter 4 and the other configuration is the same.

When the pixel pitch is 264 μm and the width of the light shielding film is set to 20 μm in each of the vertical and horizontal directions, the size of the color filter 4 is 68 × 244 (μm). In contrast, the aperture ratio {opening area} (color filter pitch × pixel pitch) × 100} is (68 × 244) / (88 × 264) × 100 = 71.
4%.

In addition, the substrate is 3 μm in each of the vertical and horizontal directions.
m, the aperture ratio becomes (65 × 241) / (88 × 264) × 100 = 67.
This is as low as 4%, which reduces the brightness and darkens the display.

In this case, in a reflection type color liquid crystal display device, the reflectance is 10 when the reflection film is a mirror (flat) specification of Al.
%.

When the width of the light shielding film is set to 10 μm in order to increase the aperture ratio and the reflectance, the aperture ratio is (78 × 254) / (88 × 264) × 100 = 85.
2%, the aperture ratio increases, and the reflectance increases to 12%.

In particular, in the reflection mode of the reflection type liquid crystal display device and the transflective type liquid crystal display device, the reflectance changes with the aperture ratio, and the brightness of the display is determined. is there.

(Example 2) In (Example 1), the columns are aligned with the respective colored layers of red (R), green (G) and blue (B), and the rows are red (R) → green (G) → blue (B)
, And the pixel groups arranged in that order are repeatedly arranged.

According to such an arrangement, as described above, the aperture ratio differs for each colored layer, and red (R) and blue (B) are 76.6%, whereas green (G) is Has a high aperture ratio of 81.9%, so that when viewed over the entire screen, green is strongly displayed, and the color tone tends to be green.

In this embodiment, furthermore, such distortion of the color tone bunras is eliminated, and the display quality is improved.

FIG. 3 shows the color filter 18a of this embodiment. According to the figure, three colors of red (R), green (G) and blue (B) are used.
Each pixel 28a, 28b, 28c is formed into a lattice by surrounding each pixel 28a, 28b, 28c with a light-shielding film 19 with one colored layer.

The columns are aligned with the respective colored layers of red (R), green (G), and blue (B).
Pixels 28 arranged in the order of red (R) → green (G) → blue (B)
a, a pixel 28b arranged in the order of blue (B) → red (R) → green (G), and a pixel 28c arranged in the order of green (G) → blue (B) → red (R). The pixels 28a, the pixels 28b, and the pixels 28c are arranged in a row repeatedly.

For the pixels 28a arranged in the order of red (R) → green (G) → blue (B), the gap between red (R) and green (G) and the gap between green (G) and blue (B) The light-shielding film 19 is not formed in the gaps, thereby increasing the aperture ratio per pixel 28a.

Similarly, the pixels 28b arranged in the order of blue (B) → red (R) → green (G) also have blue (B) and red (R).
And the gap between red (R) and green (G)
, The aperture ratio is increased, and green (G) →
The pixel 28c arranged in the order of blue (B) → red (R) also has a gap between green (G) and blue (B), blue (B) and red (R).
The aperture ratio is increased by not forming the light-shielding film 19 in the gap between the two.

By not forming the light-shielding film 19 between each colored layer in this way, the gap between both becomes 10 μm.

Then, in the pixel 28a arranged in the order of red (R) → green (G) → blue (B), red (R) and blue (B)
Are (73 × 244) / (88 × 264) × 100 = 76.
6%, and for green (G), (78 × 244) / (88 × 264) × 100 = 81.
9%, which is 78.4% on average.

For the pixel 28b arranged in the order of blue (B) → red (R) → green (G), the aperture ratios of blue (B) and green (G) are 76.6%, and red ( The aperture ratio of R) is 81.9.
%, Which is 78.4% on average.

For the pixel 28c arranged in the order of green (G) → blue (B) → red (R), the aperture ratios of green (G) and red (R) are 76.6%, and blue ( The aperture ratio of B) is 81.9.
%, Which is 78.4% on average.

As described above, each pixel 28a, 28b, 2
8c have the same average aperture ratio, so that a specific color is not emphasized. The reflectance is 1 per pixel.
1.8%.

Thus, in the use of the reflection mode of the reflective color liquid crystal display device 15 or the transflective color liquid crystal display device 15 of the present invention, by increasing the aperture ratio, the reflectance is increased and the luminance is improved. I was able to. Moreover, the light-shielding film is surrounded by each pixel unit, whereby the factor of instability of the liquid crystal due to the voltage applied to the adjacent pixel is reduced or eliminated, and as a result, the contrast is improved.

Also in the transmissive mode of the transflective color liquid crystal display device 15 of the present invention, the transmissivity was increased and the luminance was improved by increasing the aperture ratio. In addition, since the light-shielding film is surrounded by each pixel unit, the cause of the instability of the liquid crystal due to the voltage applied to the adjacent pixel is reduced or eliminated.
Improved contrast.

In addition, the average aperture ratio of each of the pixels 28a, 28b, and 28c was the same, whereby a specific color was not emphasized, the color tone balance was improved, and excellent display quality was obtained.

According to the present invention, in the color filter 18a, when the line width of the light-shielding film 19 is reduced to, for example, 10 μm, and the gap where the light-shielding film 19 is not formed is also reduced to 10 μm, the red ( Each of the aperture ratios of R) and blue (B) is (78 × 254) / (88 × 264) × 100 = 85.
2%, and for green (G), (83 × 254) / (88 × 264) × 100 = 90.
7%, or 87.0% on average. Pixel 28b or Pixel 2
8c also has an average aperture ratio of 87.0% and a reflectance of 13.1% per pixel.

However, the pixel 28a-pixel 28b-
By adopting an array configuration that repeats in the order of pixels 28c,
When regularity is generated and the pixel pitch is large, 1
Even if all of the red (R), green (G), and blue (B) coloring layers in the pixel are turned on, white may not tend to look white.

Therefore, in order to eliminate such color periodicity, it is preferable to reduce the pixel pitch (the pitch of the color filter 18).
A high-definition display panel having a size of 0 μm or less is preferable.

The present invention is not limited to the color filter 18a having the arrangement of the colored layers as described above, but may have another arrangement.

For example, the color filter 18 shown in FIG.
As shown by b, each pixel 28d, 28e, 28f is surrounded by a light shielding film 19 as one pixel 28d, 28e, 28f with three colored layers of red (R), green (G), and blue (B). It has a lattice shape.

The columns are aligned with the respective colored layers of red (R), green (G), and blue (B).
Pixels 28 arranged in the order of red (R) → blue (B) → green (G)
d, a pixel 28e arranged in the order of green (G) → red (R) → blue (B), and a pixel 28f arranged in the order of blue (B) → green (G) → red (R). The pixels 28d, the pixels 28e, and the pixels 28f are arranged in a row repeatedly.

Further, as shown in a color filter 18c shown in FIG. 5, each pixel 28g, 28h, 28i is formed by three colored layers of red (R), green (G), and blue (B). By surrounding 28 h and 28 i with the light shielding film 19,
It has a lattice shape.

Similarly, the columns are aligned with the respective colored layers of red (R), green (G) and blue (B), while the rows are aligned with blue (B) → red (R) → green (G). , A pixel 28h arranged in the order of blue (B) → green (G) → red (R), and a pixel 28h arranged in the order of green (G) → blue (B) → red (R). The pixels 28i are sequentially arranged, and are successively arranged in rows in the order of the pixels 28g, the pixels 28h, and the pixels 28i.

With respect to each of the above color filters 18b and 18c, each pixel has the same average aperture ratio, whereby a specific color is not emphasized, the color tone balance is improved, and excellent display quality is obtained. .

[0074]

As described above, in the color liquid crystal display device of the present invention, pixels each having a differently arranged colored layer arranged on a substrate are arranged in a matrix, and the pixels of this matrix-shaped pixel group are arranged in a matrix. The use of a color filter with a light-shielding film provided only in the reflective mode makes it possible to increase the aperture ratio and increase the reflectance in the reflective mode of a reflective color liquid crystal display device or a transflective color liquid crystal display device. The display quality was improved in a well-balanced manner by enhancing the overall performance.

Further, in the present invention, when the transmissive mode of the transflective color liquid crystal display device is used, the aperture ratio is increased, the transmissivity is increased, the luminance is improved, and the contrast is also increased. By improving the performance, the display quality could be improved in a well-balanced manner.

[Brief description of the drawings]

FIG. 1 is a sectional view of a liquid crystal display device of the present invention.

FIG. 2 is a plan view showing a colored layer arrangement pattern of the color filter according to the present invention.

FIG. 3 is a plan view showing a color layer arrangement pattern of another color filter according to the present invention.

FIG. 4 is a plan view showing a color layer arrangement pattern of another color filter according to the present invention.

FIG. 5 is a plan view showing a color layer arrangement pattern of another color filter according to the present invention.

FIG. 6 is a sectional view of a conventional liquid crystal display device.

FIG. 7 is a plan view showing a coloring layer arrangement pattern of a conventional color filter.

[Explanation of symbols]

 Reference Signs List 15: Color liquid crystal display device 16, 24: Transparent substrate 17a: Reflective film 17b: Semi-transmissive film 18: Color filter 19: Light-shielding film 21, 25: Transparent electrode 23, 26 ... Alignment film 22: Liquid crystal 28: Pixel R: Red Colored layer G: green colored layer B: blue colored layer

Claims (1)

[Claims] 1. A matrix comprising pixels in which different colored layers are individually arranged on a substrate, and a light-shielding film is provided only between each pixel of the matrix-shaped pixel group. On the other hand, a plurality of transparent electrodes are arranged in a stripe pattern, one substrate on which a transparent electrode group and an alignment film are sequentially laminated, and the other transparent electrode group on which a plurality of transparent electrodes are arranged in a stripe pattern. A color liquid crystal display device in which the other substrate on which an alignment film is sequentially laminated is disposed via a twisted nematic liquid crystal such that both transparent electrodes of one transparent electrode group and the other transparent electrode group are orthogonal to each other.