JPH06230349A - Color liquid crystal display element - Google Patents

Abstract

PURPOSE:To uniformize the thickness of a liquid crystal layer by specifying the size of spacers and arranging the constituting materials equiv. to the constituting materials of a display part in and out of a sealing part. CONSTITUTION:The constituting materials equiv. to the constituting materials of the display part 11 are arranged in and out of the sealing part 17 and the size of the spacers 16 to be dispersed in the sealing part 17 is set at the size obtd. by adding the size of the spacers 15 to be dispersed into the display part 11 to the total film thickness of the constituting materials, such as color filters 6 in order to control the thickness of the liquid crystal layer arranged between a pair of transparent electrode substrates 1 and 2 with high accuracy. As a result, the color liquid crystal display device which has uniform color tones, is free from unequal display and has a high contrast is attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a super word processor used in a small word processor or personal computer.
The present invention relates to a twisted nematic type color liquid crystal display device (hereinafter referred to as STN type color liquid crystal display device).

[0002]

2. Description of the Related Art STN type liquid crystal display devices are widely used in office automation equipment such as personal computers and word processors. The mainstream products are notebook type and have an outer shape of 296.
It is just A4 size of mm × 210 mm. These O
The outer shape of the liquid crystal display device that can be mounted on the A device is 250 to 26.
It must be 0 mm x 180 to 190 mm or less. However, if the display area is made small, the display becomes difficult to see, so the display area should be made as large as possible.
For example, in VGA 640 × 480 pixel display, 1
If the pixel size is 0.3mm x 0.3mm, the display area is 1
The size is 92 mm x 144 mm, and it is possible to achieve a display that is easy to see even with a notebook type.

In the STN type liquid crystal display device, minute variations in the thickness of the liquid crystal layer between the electrode substrates cause display unevenness and color unevenness, and are particularly likely to occur around the display portion where the liquid crystal thickness changes. In color display, color unevenness is more noticeable due to the thickness of the color filter, etc., compared to black and white display.
The thickness of the liquid crystal layer must be controlled more tightly.

[0004]

The gap between the electrode substrates in the STN type color liquid crystal display device is the thickness of the liquid crystal layer.
However, in a color liquid crystal display device, since a color filter, a smoothing film, and the like are arranged in the pixel display portion on the inner surface of the facing electrode substrate, a step is formed on the electrode substrate due to their shape. Due to the step, the distance between the electrode substrates drastically fluctuates, and due to the effect, the distance between the electrode substrates fluctuates widely to the periphery, which causes color unevenness, and uniform display cannot be obtained. An object of the present invention is to provide a simple matrix STN type color liquid crystal display device which solves the above-mentioned problems of the prior art and suppresses display unevenness in the display portion and its peripheral portion and makes the color tone uniform. did.

[0005]

In order to achieve the above object, in the present invention, a black stripe, a color filter, a smoothing film, an alignment film and a transparent electrode which do not contribute to the display are provided around the pixel display area and outside the seal portion. Deploy. Further, the size of the spacers dispersed in the seal portion is determined in consideration of the thickness of the black stripe, the color filter, the smoothing film, the alignment film and the transparent electrode in order to obtain the desired liquid crystal layer thickness.

[0006]

As described above, so-called dummy black stripes, color filters, smoothing films, alignment films and transparent electrodes, which do not contribute to the display, are arranged inside and outside the seal portion, and the thickness of the liquid crystal layer can be made uniform. In addition, in order to obtain the desired liquid crystal layer thickness, the size of the spacers dispersed in the seal part should be determined in consideration of the film thicknesses of the black stripe, color filter, smoothing film, alignment film and transparent electrode. Thereby, the thickness of the liquid crystal layer can be made more uniform. By such means, it is possible to obtain a highly accurate liquid crystal thickness, and thus it is possible to achieve color display without color unevenness.

[0007]

EXAMPLE In this example, the display scale is 640 (× 3) × 48.
Suitable for carrying out the present invention mainly on a display device of 0 dots (pixel pitch: 0.3 mm × 0.3 mm, pixel size: 0.27 mm × 0.27 mm, screen diagonal size: 9.4 inches) The color liquid crystal display device will be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing the structure of the color liquid crystal display device of the present invention. The color liquid crystal display element shown in the figure includes signal side and scanning side electrode substrates (material: soda lime glass, thickness: 0.7 mm) 1, 2, liquid crystal 10, scanning side electrode substrate 2 with black stripes 5, color filters 6 The smoothing film 7, the scanning side transparent electrode 4, and the alignment film 9 were formed on the display portion 11 and the peripheral portion. On the other hand, on the signal side electrode substrate 1, the signal side transparent electrode 3, the insulating film 8 and the alignment film 9 are formed on the display portion 11, and the peripheral portion 12 other than the display portion 11 and the seal portion 17 do not contribute to the display. The transparent electrodes 3, 4, the insulating film 8 and the alignment film 9 were formed. In addition, the liquid crystal 10 in the panel
In order to make the layer thickness uniform, the size of the spacers 16 dispersed in the seal portion 17 is such that the desired thickness of the liquid crystal layer 10 is the color filter 6, the smoothing film 7, the transparent electrode 3, the alignment film 9 and the insulating film 8. The size was set to be the sum of the film thicknesses of the same. With such a configuration, stress concentration does not occur in a specific portion of the electrode substrates 1 and 2 when the panel is formed, and the entire thickness of the electrode substrates 1 and 2 can be made uniform. Further, in the present invention, the color filter 6, the smoothing film 7, the alignment film 9, the insulating film 8 and the like are not formed below the seal portion 17 so as not to impair the reliability of the panel.

After forming the panel so that the gap between the electrode substrates 1 and 2 is uniform with the entire size of the electrode substrates 1 and 2 as described above, it is cut into a desired shape. As the panel becomes thinner and lighter, the thickness of the electrode substrates 1 and 2 becomes thinner and it becomes more difficult to control the thickness of the liquid crystal layer. Therefore, it is important to form the constituent film material and the sealing material at a low temperature.

FIG. 2 is a layout view of the dummy electrodes 3, 4, the color filters 6, the black stripes 5, the smoothing film 7, the insulating film 8 and the alignment film 9 of the scanning-side electrode substrate 2. As shown in the figure, a color filter 6, a black stripe 5, a smoothing film 7, a scanning side transparent electrode 4, and an alignment film 9 are arranged on the display portion 11 at the substantially center of the scanning side electrode substrate 2. Similarly, a dummy color filter 6, a dummy black stripe 5, a dummy smoothing film 7, a dummy scanning side transparent electrode 4, and a dummy alignment film 9 are arranged in the peripheral portion 12 so as to surround the display portion 11. Further, a dummy color filter 6, a dummy black stripe 5, a dummy smoothing film 7, a dummy scanning side transparent electrode 4, and a dummy alignment film 9 are arranged outside the seal portion 17 so as to surround the liquid crystal display element.

In the color liquid crystal display device of the present invention, the thickness of the liquid crystal layer and its uniformity are important factors that influence the display characteristics of brightness, contrast and color range.
In order to make the thickness of the liquid crystal layer uniform, it is desirable to form the color filter with the same smoothness as the upper and lower electrode substrates.

FIG. 3 shows the relationship between the width of the dummy area arranged inside and outside the liquid crystal display element area and the variation in the thickness of the liquid crystal layer. As shown in the figure, it was confirmed by experiments that when the liquid crystal layer thickness variation was suppressed to ± 1% or less, display unevenness did not occur and good color display was obtained. Further, as shown in the same figure, it was also confirmed that if the width of the dummy region to be arranged inside and outside the liquid crystal display element region is 3 mm or more, the liquid crystal layer thickness variation does not cause display unevenness.

(Embodiment 1) The electrode substrates 1 and 2 are 0.7 m thick soda lime glass, the signal side electrode 3 and the scanning side electrode 4
Is ITO by sputtering (sheet resistance 8Ω / □, film thickness
3000 Å), black stripe 5 is formed by photolithography method (base material: acrylic resin, dispersion material: carbon, film thickness: 1.3 μm), color filter 6 is a pigment type by printing method (film thickness: 2.2 μm) , The smoothing film 7 is formed by a single coating with a spinner (epoxy resin, film thickness:
1.0 μm), the alignment film 9 is formed by a printing method (polyimide resin, film thickness: 1000Å), the insulating film 8 is formed by a sputtering method (silicon oxide, film thickness: 1000Å), and the spacers 15 dispersed in the display portion are Polymer beads (diameter:
6.2 μm 2) and the spacers 16 dispersed in the seal portion 17 were glass fibers (diameter: 10.5 μm 2).

(Embodiment 2) The electrode substrates 1 and 2 are soda lime glass having a thickness of 0.7 m, the signal side electrode 3 and the scanning side electrode 4 are formed.
Is ITO by sputtering (sheet resistance 8Ω / □, film thickness
3000 Å), black stripe 5 is formed by photolithography (base material: acrylic resin, dispersion material: carbon, film thickness: 1.3 μm), color filter 6 is a pigment type by printing method (film thickness: 2.2 μm) , The smoothing film 7 is formed by applying twice with a spinner (epoxy resin, film thickness:
1.4 μm), the alignment film 9 is formed by a printing method (polyimide resin, film thickness: 1000Å), the insulating film 8 is formed by a sputtering method (silicon oxide, film thickness: 1000Å), and the spacers 15 dispersed in the display area are Polymer beads (diameter:
6.2 μm 2) and the spacers 16 dispersed in the seal portion 17 were glass fibers (diameter: 10.9 μm 2).

[0015]

EFFECT OF THE INVENTION The size of the spacer dispersed in the seal portion is approximately the total thickness of the constituent materials such as the color filter plus the size of the spacer dispersed in the display portion, and the size of the spacer inside and outside the seal portion is increased. A high contrast color liquid crystal display device having a uniform color tone and no display unevenness can be achieved by arranging the same constituent material as the display section.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a liquid crystal display element of the present invention.

FIG. 2 is a plan view showing a conventional liquid crystal display device.

FIG. 3 is a diagram showing the relationship between the variation of the dummy region width and the thickness of the liquid crystal layer.

[Explanation of symbols]

1 ... Signal side electrode substrate, 2 ... Scanning side electrode substrate, 3 ... Signal side transparent electrode, 4 ... Scanning side transparent electrode, 5 ... Black stripe, 6 ... Color filter, 7 ... Smoothing film, 8 ... Insulating film,
9 ... Alignment film, 10 ... Liquid crystal, 11 ... Display part, 12 ... Peripheral part, 13 ... Terminal part, 14 ... Dummy part outside liquid crystal display element, 1
5 ... Display spacer, 16 ... Seal spacer, 17 ...
adhesive.

Claims (3)

[Claims] 1. A liquid crystal display device, wherein a nematic liquid crystal sandwiched between electrode substrates has a twisted spiral structure within a range of 180 ° to 270 ° in the thickness direction, and the liquid crystal device is sandwiched. A pair of polarizing plates, and a color liquid crystal display device including a backlight and a super twisted nematic liquid crystal display device in which one or more birefringent films are arranged on at least one of the polarizing plate and the liquid crystal device. The black stripe, color filter, smoothing film, transparent electrode, alignment film, and insulating film that do not contribute to the display are arranged inside and outside the liquid crystal display element area by the electrode substrate that is larger than the liquid crystal display element and dispersed in the seal part. The diameter of the spacer to be distributed is roughly the same as the diameter of the spacer, and the black stripe, color filter, smoothing film, transparent Electrode, an alignment film and a color liquid crystal display device which is characterized in that the size obtained by adding the thickness of such insulating film. 2. The color liquid crystal display element according to claim 1, wherein in the liquid crystal display element, a dummy area in the liquid crystal display element area is arranged by 3 mm or more. 3. The color liquid crystal display element according to claim 1, wherein in the liquid crystal display element, a dummy area outside the liquid crystal display element area is arranged by 3 mm or more.