JPS60244924A - Multi-layered liquid crystal panel - Google Patents

Abstract

PURPOSE:To output information made of high-density picture elements to a multi-layered liquid crystal panel by using a composite transparent substrate having two sheets of extra-thin glass or plastic films to form the intermediate transparent substrate of the multi-layered liquid crystal panel consisting of >=2 layers. CONSTITUTION:The intermediate transparent substrate 30 is constituted with the composite glass substrate formed by adhering extra-thin glass 15 and 19 by an adhesive agent 110 and disposing transparent electrodes 16, 14. Transparent electrodes 12, 17 are further provided via a liquid crystal 13 and the transparent substrates 11, 18 are laminated on the outside thereof. The product which is made stabler than the product having the same thickness by the resilience of the resin and permits easy working is thus manufactured and the higher density is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a high-density pixel liquid crystal panel, and more particularly to a high-density pixel liquid crystal panel having multiple liquid crystal layers.

[Background of the invention]

In recent years, the development of liquid crystal display panels from black and white display to multicolor and even full color display is progressing. Compared to CRTs, liquid crystal panels are expected to have characteristics such as being smaller, thinner, lower power consumption, and easier to connect with ICs. Efforts have been made to improve the information density of information output terminals.

One is high-duty dynamic drive using a voltage averaging method, and the other is active drive using nonlinear elements such as transistor switching, MIM elements, and diodes. As a result, concrete development of full-color liquid crystal panels began at the same time as increasing pixel density.

There is a very strong demand for higher pixel density, and efforts have been made to create three-dimensional multilayers.

[Conventional technology and problems]

Multilayering of liquid crystal panels has been studied for the purpose of increasing information density, and FIG. 4 is a cross-sectional view of a two-layered liquid crystal panel as a representative example of a multilayer structure. 41.48
is a transparent substrate, 42, 44, 46, 47 are transparent electrodes, 46 is a liquid crystal, and 45 is an intermediate transparent substrate. Figure 2 shows
1 is a cross-sectional view of a color filter-type color liquid crystal panel that utilizes high resolution. 21.28 is a transparent substrate, 2
2.24.26.27 is transparent electrode, 26 is liquid crystal, 29 is color filter, 210 is adhesive layer, 211 is complete separation of color filter and liquid crystal, flatness, projective property and stability of transparent electrode, alignment force It is an ultra-thin glass or plastic film that can have the stability of
Regarding 1, patent application Sho P-8248, 58, 3, 31
).

Further, 25 is an intermediate transparent substrate related to the present invention. As a result of various experiments on the structures shown in FIGS. 4 and 2, there was a problem with the intermediate transparent substrate. If the intermediate transparent substrate that separates the upper liquid crystal layer and the lower liquid crystal layer is thick, it is not practical because of the disadvantage that interference between pixels occurs due to steps between pixels and parallax.

As a way to solve this problem, instead of providing each pixel with an upper liquid crystal layer and an upper liquid crystal layer, the screen was divided into two and divided into one liquid crystal layer and an upper liquid crystal layer. The resolution of the difference in level was not sufficient. The solution is simple and consists in reducing the thickness of the intermediate transparent substrate. However, ultra-thin glass is used for assembly of liquid crystal panels (pressure firing).
It was extremely easy to break during the process and was impractical. In addition, the completed panel always remains unstable in terms of impact resistance, making it impractical, and especially when it becomes large (for example, 50 x 50- or more), it becomes easy to break corresponding to its area.

Next, as a process problem, forming a high-density fine pattern on both sides of a single substrate has the following problems. After forming a fine pattern on one side (hereinafter referred to as A side), the other side (hereinafter referred to as side A) is
When forming a fine pattern on side B), it is necessary to cover side A with a protective film to prevent etching. Forming fine patterns on both the A side and the B side has a very poor yield compared to patterning only one side.

[Purpose of the invention]

It is an object of the present invention to provide a multilayer liquid crystal panel that eliminates the above-mentioned drawbacks, and to form a screen as an information output terminal with high pixel density.

[Embodiments of the invention]

The present invention will be explained below with reference to the drawings.

FIG. 3 is a cross-sectional view of an intermediate transparent substrate of a multilayer black-and-white liquid crystal panel according to the present invention, and FIG. 1 is a cross-sectional view showing an embodiment of a multilayer black-and-white liquid crystal panel assembled using the intermediate transparent substrate of FIG. be. The intermediate transparent substrate in FIG. 3 is an ultra-thin glass plate 61.
．． 62 is bonded with an adhesive 65, and transparent electrodes 66 and 64 are arranged on the composite glass substrate.

In FIG. 1, ultra-thin glass 15.19, adhesive layer 11
0. The transparent electrodes 14 and 16 are the same as the intermediate transparent substrate shown in FIG.
．． This is an adhesive layer on which 19 is adhered. Similarly, FIG. 5 is a sectional view of an intermediate transparent color substrate of a multilayer color I-LCD panel according to another embodiment of the invention, and FIG. FIG. 3 is a cross-sectional view of a liquid crystal panel.

The intermediate transparent color substrate in Figure 5 is ultra-thin glass 5L 52
A color filter 55 is arranged between the ultra-thin glass 5
2 and a color filter 55 are glued together, and a transparent electrode 56.5 is attached.
This is a composite glass substrate on which 4 is arranged. Of the color filters 55, 55-a is red, 55-b is green, 55-c is blue, and 56 is an adhesive layer. In FIG. 6, ultra-thin glass 65.611, adhesive 610, color filter 69, and transparent electrodes 64.66 are the same as the intermediate transparent color substrate in FIG. 5, 61.68 is a transparent substrate, and 62.67 is A transparent electrode, 66 a liquid crystal, and 610 an adhesive.

Although not shown as a color liquid crystal panel structure, basically the structure of the multilayer color liquid crystal panel shown in FIG. 2 is used, only the intermediate transparent substrate is changed, and a third transparent substrate is used as the intermediate transparent substrate.
The intermediate transparent substrate shown in the figure may also be used.

Next, we will describe each component used and the manufacturing method. The lower limit of the thickness of ultra-thin glass (for example, #0211 manufactured by Corning Co., Ltd.) is 50 μm. Since the physical properties of the glass surface do not depend on the thickness, electrode formation can be performed under exactly the same conditions as in the past, and there is no need to specially select low-temperature conditions. The adhesive is photosensitive adhesive,
It can be widely used as thermosetting adhesives, heat-sensitive adhesives, pressure-sensitive adhesives, etc. Considering the simplicity of the lamination method, it is preferable that the lamination can be carried out without bubbles under normal pressure.

Further, in order to achieve the uneven shape of the color filter surface and the flatness of the ultra-thin glass laminate (intermediate transparent substrate), a liquid adhesive such as a photosensitive adhesive or a thermosetting adhesive is preferable.

There are two methods: pressure method and rotation method. The pressure method is a method in which the coating is spread over the entire surface using pressure and then cured using light or thermal energy.The rotation method is a method in which a droplet placed between both substrates is spread over the entire surface using centrifugal force and then cured using light or thermal energy. This is a method of curing using thermal energy. Color filters are printed using printing methods.
Photolithography method, pigment vapor deposition method, pigment adsorption method, dye transfer method, etc.
There are various manufacturing methods, but there are no particular limitations.

There are no particular problems in assembling the liquid crystal panel (just apply alignment agent, rub, print sealant, lamination, inject liquid crystal, and seal the holes in the same way as before).

Next, we will talk about the parallax depending on the thickness of the intermediate transparent substrate.This parallax can be accurately calculated theoretically.

Model diagrams for theoretical calculations are shown in FIGS. 7 and 8.

In FIGS. 7 and 8, X: parallax (displacement) d: distance between CF and LC θ: angle of incidence n: refractive index of panel (substrate)! = Width of panel p, e = viewing distance ゛ql: Distance from the perpendicular to the origin, then the theoretical formula is as follows. The refractive index of the panel is set to 151 of the substrate (soda lime glass), the viewing distance is changed from 2 times to 4 times the panel screen width, and d and q, which indicate the distance between the color filter and the liquid crystal and the degree of oblique light, are changed. The calculated results are shown in the table.

n=1.51 p=2 Q 20 50 80 100 120 150 20
0 '300 d(μ)i1=lJl 1)=2.5 q20 50 80 100 120 150 200
300 d(μ) 4, 13 33 54 67 8
1 101 135 203n =1.51 p=3 Q 20 50 80 100 120 150 20
0 300 d(μ) o ooo o o o o o.

O,52581013162132 1410172125324264 1,56152431374662932719313
9475978118 2592337465670931403102642
52637910515841231496274'
93 124 187n=1.51 1)=35 q20 50 so 100 120 150 200
300 d(μ) o ooo o o o o o.

1.5 5 13 21 27 32 40 54 8
13 9 23 38 47 57 71 95 14
33.5 10 26 42 52 63 79 10
5 1584 11 28 45 57 68 86
114 172n==1.5] p24 q 20 50 80 100 120 150 20
0 300 d(μ) The image of a liquid crystal panel is limited to a viewing angle. In particular, this tendency is most pronounced in the TN type passive type system. In general, the viewing distance is considered to be three times the screen, so p = 3, and as a specific example, the number of scanning lines,
Aperture ratio (important element for image brightness and contrast),
As a result of studying large-screen fine pattern formation (particularly the occurrence of wire breaks), we decided to increase the pixel spacing of the double system to 60μ (fine line width: 15μ).
, the electrode wiring spacing was 15 μm). LCD panel,
In particular, TN type passive panels are generally used one-on-one by a machine and a human, and are used in accordance with the preferred viewing angle direction, so it is not necessary to set q to 3.4 or a large value.

For these reasons, when q is 1, the thickness of the ultra-thin glass needs to be 300 μm or less.

This was particularly important for color shifts in color images.

〔Effect of the invention〕

As is clear from the above embodiments, according to the present invention, (1) The formation of fine patterns on ultra-thin glass can be performed only on one side, which is very advantageous in terms of yield.

■ By installing a resin layer (adhesive layer) between the layers of ultra-thin glass, the resin becomes more flexible and is more stable than thin glass of the same thickness.

This composite glass structure was very effective in the pressurizing process of LCD panel assembly and in the impact test of the completed product.

■ In a color liquid crystal panel, the color filter layer and liquid crystal layer can be completely separated, preventing discoloration of the color filter due to chemical interaction and preventing impurities from diffusing into the liquid crystal.

As described above, by using a substrate with a composite glass structure of ultra-thin glass as the intermediate transparent substrate of a multilayer liquid crystal panel,
We were able to achieve high density, which is the goal of information terminal equipment. Note that the counter substrate is a passive substrate or an active substrate (TPT).

MIM, diode, etc.) may be used, and is not particularly limited. The liquid crystal display method uses a pair of polarizing plates.
There are no particular limitations, such as N-type, GHW in which dye is dissolved in liquid crystal, etc. (although they may be used in combination.

Furthermore, the electrodes may not only be transparent electrodes, but may also include metal wiring in order to lower the resistance. Further, although the explanation has been given using a two-layer liquid crystal panel as an example, a panel having three or more layers may be used.

[Brief explanation of the drawing]

4 and 2 are cross-sectional views showing the prior art, in which FIG. 4 shows a multilayer black and white liquid crystal panel, FIG. 2 shows a multilayer color liquid crystal panel, and FIGS. 3 and 1 show an embodiment of the present invention. 3 is a sectional view of a composite glass substrate, FIG. 1 is a multilayer black and white liquid crystal panel using the composite glass substrate of FIG. 3, and FIGS. 5 and 6 are sectional views of other embodiments of the present invention. Figure 5 shows a composite glass substrate containing a color filter, Figure 6 shows a multilayer color liquid crystal panel using the composite glass substrate shown in Figure 5, and Figures 7 and 8 are model diagrams for theoretical calculations. be. 11.18.61.68...Transparent substrate, 16.
66...LCD, 15.19.61.32.51.52.65.611.
...Ultra-thin glass, 12.14.16.17.66.34.53.54.6
2.64.66.67...Transparent electrode, 35.6
10...Adhesive, 55.69...Color filter, 56.11
0...Adhesive layer. Patent applicant Citizen Watch Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 4vR Figure 6

Claims (3)

[Claims] (1) In a multilayer liquid crystal panel with two or more liquid crystal layers,
A multilayer liquid crystal panel characterized in that the intermediate transparent substrate is composed of a composite transparent substrate having two ultra-thin glass or plastic films. (2) The multilayer liquid crystal panel according to claim 1, wherein the total thickness of the composite transparent substrate is 300 μm or less. (3) The multilayer liquid crystal panel according to claim 1, wherein a color filter layer is provided between the composite transparent substrates.