JPH11149070A - Liquid crystal element - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent the occurrence of switching failure of liquid crystal when the definition is increased and to prevent the color balance from being lost. SOLUTION: In a simple matrix type liquid crystal panel for performing color display, four bits adjacent to each other are constituted by two bits having a large area and two narrow bits having a half area as shown in the figure. The two wider bits include color filters 6R and 6 of two of the three colors RGB.
G is arranged, and the remaining one color filter 6B, 6B is arranged in the narrower two bits. Thus, even when the definition is increased to about 282 dpi, the minimum width of the bit can be made larger than 20 μm, and the occurrence of switching failure of the liquid crystal can be prevented. Also a wide bit
By setting the area ratio between the bit and the narrow bit to 2: 1, the areas of the three color filters 6R, 6G, and 6B can be made equal, and the color balance can be prevented from being lost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal device for displaying information using liquid crystal, and more particularly, to a liquid crystal device for performing color display.

[0002]

2. Description of the Related Art Hitherto, various types of liquid crystal elements for performing color display (hereinafter referred to as "liquid crystal panels") have been proposed.

[0003] Figure 1 is a cross-sectional view showing an example of a structure of a conventional simple matrix liquid crystal panel, the liquid crystal panel P _1, the pair of substrates arranged to face each other 1
a, 1b, these substrates 1a, 1b are bonded together by a sealing material (not shown), and a liquid crystal 3 is sandwiched in the internal gap.

[0004] On the surface of one substrate 1b, a large number of scanning electrodes 9b in the form of stripes are formed, and these scanning electrodes 9b are covered with an insulating film or alignment film (not shown).

On the surface of the other substrate 1a, R (R
ed) color, G (Green) color, B (Blue) color
A color filter 6 of color is arranged (hereinafter, a color filter of R color is referred to as “color filter 6R”,
The color filter of G color is referred to as “color filter 6G”, and the color filter of B color is referred to as “color filter 6G”.
B ", and if no particular color is specified, it is simply referred to as" color filter 6 "), and a light-shielding pattern 5 is formed between these color filters 6. Further, these color filters 6 are flattened. A large number of stripe-shaped information electrodes 9a are formed on the surface of the planarizing film 7. These information electrodes 9a are covered with an insulating film or an alignment film (not shown). .

FIG. 2 shows a light shielding pattern 5, a scanning electrode 9b,
FIG. 3 is a schematic diagram showing the shapes and positional relationships of information electrodes 9a and color filters 6, where a light-shielding pattern 5 is formed in a lattice shape, and three adjacent window-like portions (portions where no light-shielding pattern 5 is formed). , And hereinafter referred to as “bit”) includes three color filters 6R,
6G and 6B are arranged respectively, and these three bi
One pixel is constituted by t.

The scanning electrodes 9b are arranged in the horizontal direction in the drawing so as to cover each bit, and the information electrodes 9a are arranged in the vertical direction in the drawing so as to cover each bit. That is, these electrodes 9a and 9b are arranged so as to form a matrix electrode at right angles.

[0008]

[SUMMARY OF THE INVENTION Incidentally, although a rubbing treatment is performed on the alignment film at the stage of manufacturing the liquid crystal panel P ₁ described above, for example, facilities rubbed in a direction indicated by reference numeral 10 in FIG. 2 when the switching failure were to occur in the region shown by reference numeral a in driving the liquid crystal panel P _1. The switching failure region is caused by the relationship between the step of the electrode and the rubbing process, and also occurs in the color filters 6R and 6G (not shown).

On the other hand, in recent years, it has been desired that the liquid crystal panel having the above structure be improved in definition to enhance display quality. However, when the definition is increased to 250 dpi or more, each bit is reduced.
Is too small (about 12 μm as will be described later), and the proportion of the switching failure area A increases, resulting in a problem that the display quality of the entire screen deteriorates.

Here, when the definition is 282 dpi, the width of the bit (the size indicated by the symbol i in FIG. 2) is calculated.

When the definition is 282 dpi, the pitch of one pixel (that is, the width of one pixel, which is indicated by a ₁ in the drawing) is:

[0012]

(Equation 1) Becomes Now, assuming that a strip-shaped portion formed in the illustrated vertical direction in the light-shielding pattern 5 is “vertical lattice 5a”, the pitch of the vertical lattice 5a (the pitch of the center line of the adjacent vertical lattice 5a, dimension indicated by the symbol "a _1/3" in)
Is 90 μm ÷ 3 = 30 μm. And vertical lattice 5
and the width b ₁ of a and 18 [mu] m, the width dimension i of the bit 3
0 μm−18 μm = 12 μm. In addition, assuming that the strip-shaped portion formed in the horizontal direction in the drawing is “horizontal lattice element 5b”,
The pitch of the transverse grating element 5b (a pitch of the center line of the adjacent transverse lattice element 5b, the dimensions indicated by the symbol a _2), upon 90μm, and the width b ₂ of the horizontal grating element 5b and 18 [mu] m, bit
Is 90 μm−18 μm = 72 μm.

Further, as described above, in the liquid crystal panel having the structure in which the three color filters 6 are arranged in a line, the center bi
When the bits on both sides excluding t were turned on, there was also a problem that the resolution seemed to be slightly inferior because these bits were far apart.

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal element which reduces the influence of liquid crystal switching failure when the definition is increased.

Another object of the present invention is to provide a liquid crystal element which prevents the resolution from appearing inferior.

Another object of the present invention is to provide a liquid crystal element which prevents color balance from being lost.

[0017]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and includes a pair of substrates arranged to face each other, a liquid crystal sandwiched between the pair of substrates, A plurality of scan electrodes formed on one of the base materials, a plurality of information electrodes formed on the other base so as to intersect with the plurality of scan electrodes, and a crossing portion of these electrodes. In a liquid crystal element having a plurality of color filters on one base material side so as to be arranged and a plurality of pixels capable of multicolor display with a predetermined number of intersections as a set, two adjacent scans are provided. It is characterized in that three color filters of RGB are arranged at four intersections formed by electrodes and two adjacent information electrodes, and one pixel is constituted by these four intersections.

In this case, the four intersections are approximately 2:
The color filters are configured with an area ratio of 2: 1: 1. Two color filters of three colors are arranged at two intersections having a large area, and the remaining one is arranged at the other two intersections. Preferably, a color filter of a color is arranged.

[0019]

Embodiments of the present invention will be described below with reference to FIG. Note that the same parts as those shown in FIG.

As shown in FIG. 3, a liquid crystal element P _{2 according} to the present invention comprises a pair of base materials 1a,
1b, the liquid crystal 3 sandwiched between the pair of substrates 1a, 1b, a plurality of information electrodes 9a formed on one of the pair of substrates 1a, and a plurality of the information electrodes 9a.
A plurality of scanning electrodes 9b formed on the other substrate 1b so as to intersect, and a plurality of color filters 6 arranged at the intersections of these electrodes 9a and 9b. Further, two adjacent information electrodes 9a and two adjacent information electrodes 9a
A color filter 6 of three colors RGB is arranged at four intersections constituted by the scanning electrodes 9b, and one pixel capable of multicolor display is formed by setting these four intersections as one set. Have been.

In this case, two of the four intersections have a color filter 6 of two of the three colors.
Are arranged respectively, and the other two intersections have the remaining 1
It is preferable that a color filter 6 of a color is arranged.

Also, the four intersections are substantially 2: 2:
Two color filters 6 of three colors are arranged at two intersections having a large area, respectively, and the other two intersections have one remaining color at two intersections having a large area. Is preferably arranged.

The pair of substrates 1a and 1b and the electrodes 9a and 9b are made of a transparent material so that the liquid crystal element P
₂ may be a transmissive type. In this case, if the area ratio of the light transmitting region in the four color filters 6 arranged at the four intersections is approximately 2: 2: 1: 1. good.

Further, color filters 6R and 6G of two colors RG are arranged at the two intersections having the large area, and color filters 6B and 6B of the B color are arranged at the other two intersections. You may do so.

Next, effects of the present embodiment will be described.

According to the present embodiment, one pixel is constituted by a set of four intersections formed by two adjacent information electrodes 9a and two adjacent scan electrodes 9b. Even if the definition is increased to about 250 dpi or more, the minimum width of the intersection (1 bit) becomes larger than before.
Therefore, when the rubbing direction is set to the direction indicated by reference numeral 10 for such a pixel, one of the regions where switching failure occurs (corresponding to 6G and 6R) as shown by the region A in FIG. The ratio of the area occupied by one color (bit) is reduced, and the influence of the switching failure of the liquid crystal on the display quality can be reduced.

Further, according to the present embodiment, as described above, one pixel is configured by setting four adjacent intersections as a set. Therefore, the three color filters 6 are arranged adjacent to each other, and it does not appear that the resolution is inferior even when any of the intersections is turned on.

In addition, the four intersections are approximately 2: 2:
Two color filters 6 of three colors are arranged at two intersections having a large area, respectively, and the other two intersections have one remaining color at two intersections having a large area. When the color filters 6 are arranged, the color filters 6 of three colors have the same area, and the color balance can be prevented from being lost.

By the way, although the B color is originally a color lacking in visibility, this B color filter 6B is arranged at the intersection of a small area (the two intersections of a large area are RG2).
In the case where the color filters 6R and 6G of colors are disposed), even if a switching failure occurs at the intersection of the narrow area, the influence on the image quality of the entire liquid crystal element can be reduced. That is, the width dimension i (that is, the width dimension i)
The width j (that is, the width of the bit on which the color filter 6B is disposed) is smaller than the width of the bit on which the color filters 6R and 6G are disposed, and the rubbing direction 10 in FIG. At first glance, the area ratio of the region where such a switching failure may occur becomes large, but the influence on the image quality is small due to the low visibility of B.

As shown in FIGS. 5 and 6, the same configuration can be applied to a case where auxiliary electrodes (20a, 20b) are attached to the scanning electrodes or the information electrodes.

Further, in the configurations shown in FIGS. 3 to 6, the arrangement of the RGB color filters is changed (for example,
Although a small color filter can be arranged above one pixel in FIG. 4), it is preferable to adjust the relationship between the arrangement of the color filters and the direction of the rubbing process so that the area of the switching failure is most inconspicuous.

[0032]

The present invention will be described below in more detail with reference to examples.

[0033] Example 1 In this Example, was prepared a liquid crystal panel P ₂ shown in FIG.

Note that glass substrates were used for the substrates 1a and 1b. Further, R (Red) color, G (Green) color, B
The three color filters (Blue) 6 are formed on the surface of one glass substrate 1a and have a thickness of 1.5 μm.
And Further, a light-shielding pattern 15 made of MoTa alloy and having a thickness of 1000 ° was formed between the color filters 6. Furthermore, color filter 6
Is coated with a flattening film 7 (PSBK-31, manufactured by Toray Industries, Inc., thickness (maximum thickness on the light-shielding pattern) 2.0 μm).

On the other hand, the scanning electrode 9b and the information electrode 9a
Both were formed of ITO (indium tin oxide), the thickness was 3000 mm, and the shape was a stripe. Of these, the scanning electrode 9b was formed on the surface of one glass substrate 1b, and the information electrode 9a was formed on the surface of the flattening film 7.
These scanning electrodes 9b and information electrodes 9a are formed of insulating films (90
(Ta ₂ O ₅ ) having a thickness of 0 ° and an orientation film (a polyimide film having a thickness of 500 °).

Further, the light shielding pattern 15, the scanning electrode 9b,
The shape and positional relationship of the information electrode 9a and the color filter 6 were as shown in FIG.

The light-shielding pattern 15 was formed in a lattice. In the present specification, a band-shaped portion formed in the illustrated vertical direction in the light-shielding pattern 15 is referred to as a "vertical lattice 15a", and a band-shaped portion formed in the illustrated horizontal direction is referred to as a "horizontal lattice 15b".
However, these vertical lattice elements 15a and horizontal lattice elements 15b
Are all unified at 18 μm. Also, the horizontal lattice 15
The pitch b (the pitch of the center line of the adjacent horizontal lattice elements 15b, the dimension indicated by the symbol e) was 45 μm and uniform. Further, the pitch of the vertical lattice elements 15a (the pitch of the center line of the adjacent vertical lattice elements 15a) is a wide pitch (54 μm) indicated by the symbol f and a narrow pitch (36 μm) indicated by the symbol g in the drawing.
μm), and these wide and narrow pitches f and g are alternately arranged. Thereby, the vertical lattice 15a
And a window-like portion (hereinafter, referred to as “bit”) defined by the horizontal lattice 15b has a wide bit and a narrow bit.
And the area of a wide bit (h × i = 27 μm × 36
μm) and the area of a narrow bit (h × j = 27 μm × 18μ)
m) is approximately 2: 1.

The two wider bits include color filters 6R and 6R of two of the three colors (R and G).
G, and color filters 6B, 6B of the remaining one color (B color) are arranged in the two narrower bits.
Color filters 6R, 6R arranged in these 4 bits
The area ratio of G, 6B, 6B was set to be approximately 2: 2: 1: 1. That is, the three color filters 6R, 6R
G, 6B (the total area of the two color filters 6B) is made equal, and these four bi
A single pixel capable of multi-color display was constructed using t as a set.

On the other hand, all the information electrodes 9a have a width of 37 μm.
m, and arranged along the horizontal lattice 15b so as to cover each bit. The scanning electrodes 9b are such that scanning electrodes 9b having a narrow width (28 μm) and scanning electrodes 9b having a wide width (46 μm) are alternately arranged, and are arranged along the vertical lattice 15a so as to cover each bit. Thereby, the information electrode 9a and the scanning electrode 9b
Are arranged so as to be orthogonal to each other, and the intersection of these electrodes 9a and 9b coincides with the above-mentioned bit. In addition, the color filters 6 for the three colors RGB are
It is arranged at four intersections constituted by two adjacent scanning electrodes 9b and two adjacent information electrodes 9a.

The width of the scanning electrode 9b and the information electrode 9
Since the width a is the above-mentioned size, each electrode 9a, 9b and each lattice element 15a, 15b overlap with a width of 5 μm (refer to the symbol d in the figure), and as a result, fabrication within that range is performed. An error will be tolerated. Also, the scanning electrode 9b
The gap c between the information electrodes 9a and the gap c between the information electrodes 9a are both 8 μm. Further, the dimension indicated by the symbol a (dimension corresponding to the width of one pixel) is 90 μm, and the definition is

[0041]

(Equation 2) Becomes

Next, a method for manufacturing the liquid crystal panel P _2.

First, a MoTa alloy film was formed to a thickness of 1000 ° on the entire surface of one glass substrate 1a by sputtering. The power was set to 2.2 kW and the pressure was set to 5 mTorr. Then, a resist is applied to the surface of the MoTa alloy film, pre-baked, and further exposed to light.
By performing development and etching, the MoTa alloy film was patterned in a lattice shape, and the light-shielding pattern 15 having the above-described shape was formed. Thereafter, the remaining resist was removed.

Next, a resin in which an R color pigment is dispersed is applied to the entire surface of the glass substrate 1a, and thereafter, patterning and post-baking are performed by a photolithography method to obtain
At time t, an R color filter 6R was formed to a thickness of 1.5 μm. Note that the photolithography method was performed by applying a resist on the surface of the resin, performing prebaking, and then performing exposure, development, and postbaking. G and B color filters 6G and 6B were also formed in the same manner.

The surface of the color filter 6 thus formed is spin-coated with a transparent resin (1000).
rpm, 15 sec), and further post-bake,
A flattening film 7 was formed.

Further, the surface of the flattening film 7 is coated with ITO.
A transparent conductive film made of (indium tin oxide) was formed to a thickness of 3000 ° by sputtering, and then patterned by photolithographic etching to form an information electrode 9a. Then, an insulating film was formed by a sputtering method, and an alignment film was formed by a printing method.

Also, the surface of the other glass substrate 1b is
The scanning electrode 9b was formed in the same manner as the information electrode 9a.
Then, similarly, an insulating film was formed by a sputtering method, and an alignment film was formed by a printing method.

Further, one of the glass substrates 1a,
A sealing material was applied to 1b along the edge, and a pair of glass substrates 1a and 1b were bonded via a spacer (particle diameter: 1.2 μm) such that the information electrode 9a and the scanning electrode 9b were orthogonal to each other.

[0049] Thereafter, the glass substrate 1a, the inside gap 1b is injected smectic C liquid crystal 3 to prepare a liquid crystal panel P _2.

The inventor of the present invention has actually driven the produced liquid crystal panel, and was able to display a high-definition and high-quality image. Further, the same effects as those described in the embodiment of the present invention were obtained.

In the above embodiment, the R and G color filters 6R and 6G are arranged in the two wider bits, respectively, and the B color filter 6B is arranged in the two narrower bits. Although they were arranged, the same effect was obtained even if the combination of these colors was changed.

(Embodiment 2) In this embodiment, FIGS.
We have created a liquid crystal panel P ₃ shown in.

The auxiliary electrodes 20b and 2b are arranged on the surfaces of the scanning electrode 9b and the information electrode 9a along the longer edge.
0a was arranged. These auxiliary electrodes 20b, 20a
Aluminum alloy (Al: Si: Cr = 98.5: 1.0:
1.5), with a thickness of 1000 mm and a width (FIG. 6).
(Reference sign k)) was set to 6 μm. In addition, light shielding pattern 1
5, the width b of the vertical lattice 15a and the horizontal lattice 15b
Is larger than that of the first embodiment by the width k of the auxiliary electrodes 20b and 20a, and is set to 24 μm. Among the pitches of the vertical lattice, the wider (f) is set to 52 μm and the narrower (g) is set to 38 μm. This was the same as in Example 1 (see FIG. 6). Therefore, in this embodiment, the size of the wider bit is h × i
= 21 μm × 28 μm, and the dimension of the narrower bit is h
× j = 21 μm × 14 μm.

In forming the auxiliary electrode, an aluminum alloy film was formed by sputtering, and was patterned by photolithographic etching.
The power was set to 2.6 kW and the sputtering temperature was set to 150 ° C.

The other configurations and the manufacturing method were the same as those in the first embodiment.

According to this embodiment, the same effects as those of the first embodiment were obtained.

Generally, the switching failure area (see reference numeral A in FIG. 2) extends from the edge of the scanning electrode 9b (the edge on the upstream side in the rubbing direction) toward the downstream side in the rubbing direction (10). However, in the present embodiment, the width b of the light-shielding pattern 15 is larger than that in the first embodiment, so that even if a switching failure occurs, most of the defective area is hidden by the light-shielding pattern 15. Therefore, the effect of the switching failure on the image quality can be further reduced as compared with the first embodiment.

Further, the resistance value of the electrode was reduced to one fifth of that without the auxiliary electrode (Example 1), and the delay of the driving waveform was eliminated.

[0059]

As described above, according to the present invention,
Since one pixel is composed of four intersections formed by two adjacent scanning electrodes and two adjacent information electrodes, even if the definition is increased to about 250 dpi or more, the intersection is obtained. Is greater than 12 μm. Therefore, the influence of the switching failure of the liquid crystal on the display quality can be reduced.

In addition, the three color filters are arranged adjacent to each other, and it does not appear that the resolution is inferior when any of the intersections is turned on.

In addition, the four intersections are substantially 2: 2:
The color filters are configured with an area ratio of 1: 1. Two color filters of three colors are respectively arranged at two intersections having a large area, and the other two intersections have the remaining one color filter. When the color filters are arranged, the three color filters have the same area, and the color balance can be prevented from being lost.

Furthermore, although the B color is originally a color lacking in visibility, this B color filter is arranged at the intersection of a small area (two color filters of RG are arranged at two intersections of a large area). In this case, even if a switching failure occurs at the intersection of the narrow area,
The influence on the image quality of the entire liquid crystal element can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of the structure of a conventional simple matrix type liquid crystal panel.

FIG. 2 is a schematic diagram showing shapes and positional relationships of a light-shielding pattern 5, an information electrode 9a, a scanning electrode 9b, and a color filter 6 in a conventional liquid crystal panel.

FIG. 3 is a cross-sectional view illustrating an example of a structure of a liquid crystal panel according to the present invention.

FIG. 4 is a schematic diagram showing the shapes and positional relationships of a light-shielding pattern 15, information electrodes 9a, scanning electrodes 9b, and color filters 6 in a liquid crystal panel according to the present invention.

FIG. 5 is a sectional view showing another example of the structure of the liquid crystal panel according to the present invention.

FIG. 6 is a schematic diagram showing the shape and positional relationship of a light-shielding pattern 15, information electrodes 9a, scanning electrodes 9b, and color filters 6 in a liquid crystal panel according to the present invention.

[Explanation of symbols]

1a, 1b glass substrate (substrate) 3 crystal 6 color filters 9a Information electrode 9b scan electrodes P ₂ (liquid crystal element)

Claims (5)

[Claims] A pair of base materials disposed so as to face each other, a liquid crystal sandwiched between the pair of base materials, a plurality of scanning electrodes formed on one of the pair of base materials, A plurality of information electrodes formed on the other base material so as to intersect with the plurality of scan electrodes, and a plurality of color filters on one base material side to be arranged at the intersections of these electrodes, In a liquid crystal element having a plurality of pixels capable of multicolor display with a predetermined number of intersections as a set, four intersections formed by two adjacent scanning electrodes and two adjacent information electrodes are provided. A liquid crystal device comprising: a color filter for three colors of RGB; and a pixel formed by these four intersections. 2. A color filter for two of three colors is disposed at two of the four intersections, and a color filter of the other one is provided at the other two intersections. The liquid crystal device according to claim 1, wherein a filter is arranged. 3. The method according to claim 1, wherein the four intersections are approximately 2: 2: 1: 1.
And the intersection of two large areas is 3
The liquid crystal device according to claim 1, wherein two color filters of the colors are respectively disposed, and a remaining one color filter is disposed at the other two intersections. 4. 4. A color filter for two colors of RG is arranged at two intersections having a large area, and a color filter of B color is arranged at the other two intersections. 3. The liquid crystal element according to 3. 5. An R electrode on a side of the substrate on which the information electrodes are formed.
The liquid crystal device according to claim 1, wherein a color filter for three colors of GB is provided.