JPS5837619A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To provide a titled element which is produced in higher yields, is thin, does not form any double images and is suited for indicating scales, display plates, etc. of various measuring instruments by sandwiching liquid crystals between an electrode plates having electrodes on a polarizing plate and an electrode plate having a counter electrode. CONSTITUTION:For example, transparent electrodes 2 and an electrochromic storage layer 3 are provided successively on a glass substrate 1, and after a transparent photoconductive material layer 4 such as polyvinyl carbazole, CdS or the like is laminated on the layer 2, transparent electrodes 2' are formed on the layer 4. A polarizing plate (insulation plate) 5 is formed on the layer 4 and transparent electrodes 2'' is formed thereon. A spacer 6 is provided. On the other hand, a polarizing plate 5' is provided on the substrate 1' and the substrate laminated with transparent electrodes 2''' on the plate 5' is superposed via the spacer 6. A liquid crystal compsn. 7 is sealed between such substrates. In such a way the plates 5, 5' are provided under the inner electrodes 2'', 2''' without providing the same on the outer side of the substrates. Thus the yield of production is improved, and the liquid crystal element which is thin, does not form any double images and is suited for displaying of information in camera finders and displaying for power meters is obtained in high yields.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid crystal display element, and more particularly to a liquid crystal display element equipped with an electrode plate in which electrodes are formed directly on a polarizing plate.

Conventional liquid crystal display elements use a liquid crystal cell with a structure in which liquid crystal is placed in a gap formed by a pair of glass electrode plates, and one or a pair of biased plates are placed outside the liquid crystal cell. . However, when attaching such a liquid crystal display element to various devices for use in displaying information in a camera's viewfinder or power meter display, for example, the polarizing plate in the liquid crystal display element must be attached to the outside of the glass electrode plate using an adhesive. Therefore, it is necessary to attach a pair of glass electrode plates between a pair of polarizing plates in a reflective liquid crystal display element. Therefore, the distance between the two polarizing plates is large, and the thickness of the display element is correspondingly thick, and double images are generated.

An object of the present invention is to provide a liquid crystal display element with improved manufacturing yield.

Another object of the present invention is to provide a thin and double-image generation "/I".
``Our goal is to provide a high quality liquid crystal display element.

This object of the present invention is achieved by a liquid crystal display element in which a liquid crystal is sandwiched between an electrode plate having an electrode on a polarizing plate and an electrode plate having an electrode facing the polarizing plate.

The function of the display element according to the present invention can be effectively used in the indicator scale 9 display board 2 display element of various measuring instruments. It is particularly useful when it has translucency and color display is effective, such as information display in the finder of a camera or the like.

In addition, the liquid crystal display cell used in the present invention has the following functions among various liquid crystal display cells, and when combined with one that indicates operation, it is especially possible to display linear position and store it, so it is suitable for measuring instruments. By using a similar display element, it is useful as a composite liquid crystal display element.

The display method of a liquid crystal cell according to the present invention includes a first resistive layer provided on the surface of one of two opposing substrates, at least one of which is transparent, and a liquid crystal cell between a first resistive layer provided on the surface of one of the substrates and the resistive layer of the other substrate. are sandwiched, and among the layers, at least a layer provided on the surface of the transparent substrate applies a potential distribution in the surface direction of the first resistance layer of the liquid crystal cell, and the layer provided on the surface of the conductive layer or the second layer is transparent. By setting the potential at at least one point on the surface of the resistive layer to a potential within the potential distribution, a potential difference distribution is provided between the first resistive layer and the conductive layer or the second resistive layer, and the potential difference within the potential difference distribution is set. Display is performed in a potential difference region that does not exceed the electro-optical threshold of the liquid crystal.

be able to.

According to such a liquid crystal display method, the desired commercial contrast can be easily obtained, the display of negative and positive examples can be arbitrarily selected, color display is essentially possible, and the boundary area of the display area can be easily obtained. Can be distinguished by clear contrast. Display including analog calculation functions can be performed by using two or more control voltages. Practical use of the threshold temperature dependence of liquid crystals - Ignore it. Since it is essentially an electric field operation, it has many advantages in terms of the life span of the liquid crystal cell and the structure of the electrodes compared to current operation of 1til+.The basic structure of the liquid crystal cell is that the electrodes are formed on the substrate surface in a planar shape. It is extremely easy to do (alignment of upper and lower electrodes, 1) 1
Did it differentiate? This method has many advantages over conventional liquid crystal display methods, such as the need for a mask to form the I'C pole'x, and shows remarkable effects.

On the other hand, the present invention can be used in conjunction with a display/memory method based on laminated formation of memory materials.

Chalcogenide glass, photochromy, and electrochromy are examples of memory materials that have optical transparency and reversibility.

However, although chalcogenide glass exhibits good optical transparency, it has drawbacks such as low memory pattern contrast and inability to operate effectively at low voltage, and photochromy also has good optical transparency. However, there are problems with memory pattern contrast and longevity, and the biggest drawback is that the response characteristics are not good.

Electrochromy exhibits characteristics that improve each of the above-mentioned drawbacks. High light transmittance, pattern sieve contrast,
It has many features such as multicolor display, long life, high responsiveness, and low ↑IL flow operation.

The electrochromic color-forming layer used in the present invention develops or changes color when energized, maintains this state for a long time even when the energization is turned off, and is reversibly decolored or discolored by energization with the polarity opposite to that of the energization. It has the property of returning to its original color.In particular, the electrochromic color-forming substance used in the present invention is composed of a transition metal compound, a transition metal compound and a metal, and also contains alloys and other 5n02-F.
eCl2. An organic compound that exhibits electron donating or accepting properties to quaternary alloys such as Ti02-MoCe2.

It is a mixture of electrolyte substances. A specific example is Cd
O, Ag2O, 111VO2, H2MOO4, Na2M
oO4, Sn02-Mo, etc.

Furthermore, in order for the light that has passed through the liquid crystal layer to be stored in the electrochromic layer, it is necessary to generate color in response to the light. If a highly transparent photoconductive material is used, electrochromy can be effectively colored and observed.

Hereinafter, based on an embodiment, a detailed explanation will be given using the drawings together with the basic operation method.

FIGS. 1 and 2 are diagrams for explaining an example of electro-optical characteristics of a liquid crystal cell used in a liquid crystal display element of the present invention.

In Figure 2, the horizontal axis shows voltage and the vertical axis shows the amount of transmitted light. Figure 1 shows the characteristics of a field effect torsionally aligned liquid crystal (hereinafter abbreviated as TN effect), and Figure 2 shows the characteristics of a field effect vertically aligned liquid crystal (hereinafter abbreviated as TN effect).
This is a characteristic of the Fu effect (hereinafter abbreviated as the Fu effect). The characteristics of the TN effect are white light, and those due to the DAP effect are λ1. λ2. Measurements were made using monochromatic light using three wavelengths of λ3. The voltage at which electro-optic modulation begins to occur is defined as the threshold voltage, and vth
It is shown by . The TN effect has a Vtb of about 1 to 3 volts, and the low (1) AP effect has a threshold value of 6 to 6 volts, which are both sufficiently lower than the DAM effect of 8 to 15 volts.

In addition, TN is an electric field effect that exhibits low tone characteristics.

There are modifications to the DAP effect, and these have been achieved by modifying the alignment of liquid crystals or modifying display detection methods using polarizing plates or the like. There is also a method in which a dichroic dye is added to the liquid crystal layer so that color changes due to alignment changes can be directly identified without using a polarizing plate.

Although all of the liquid crystal display cells having these threshold characteristics can be applied to the liquid crystal display element of the present invention, the liquid crystal display cell having the lowest threshold value among currently known liquid crystal display cells is applicable to the liquid crystal display element of the present invention.
Liquid crystal display cells are particularly effective.

FIG. 6(a) shows the potential distribution generated by the resistive layer 3' with a uniform voltage across the lines ``AB'' in FIG. 4A.

On the other hand, if 5" in FIG. 4 is composed of a low resistance layer or a conductive layer that has a resistance sufficiently lower than that of the resistance layer 6/, the applied voltage does not change depending on the position of l, so the horizontal level of Cc The voltage distribution generated in the liquid crystal cell 1 is represented by a straight line AB and a straight line CC/, and is shown by several arrows in FIG. 6, but in reality, The voltage distribution is continuous.

The electro-optical properties of the liquid crystal used in the present invention include polarity (±
) (directivity), and therefore its threshold value is 11'' of ±vth with CO2 as the center, i.e., 2 vth. No modulation occurs.

FIG. 6(b) shows the display state in such a case, and the non-modulated area (1) corresponding to 111'1 represents the display part for the entire display area surrounded by a square. .

As described above, in the present invention, by making the area (Ill) exceeding the threshold value sufficiently large, it is possible to provide an apparent two-dot or linear display in the area (I) where the liquid crystal threshold value is not exceeded.

That is, according to the display method according to the present invention, arbitrary changes can be made within the entire display area due to changes in the potential gradient between AB (represented by the slope of the line 1lAB) and changes in the potential level of C (represented by the vertical movement of the line CC/). It can be displayed steplessly at any position and with any line width. In other words, complete analog display is possible.

Next, the material, manufacturing method, and structure of the liquid crystal display element of the present invention will be explained, and furthermore, operation examples and modified examples of the display method using the liquid crystal display cell of the basic structure will be explained.

First, referring to FIG. 5, a transparent electrode 2 is formed on a glass substrate 1''2 using, for example, a vapor-deposited film of tin oxide.After that, an electrochromic memory layer 3, such as an electrochromic film based on tungsten trioxide, is formed on a glass substrate 1''2. A photoconductive material layer 4, a transparent type @I2', is provided on the chromie coloring layer, for example, a layer of a relatively transparent photoconductive material such as polyvinylcarbazole CdS. Further, a transparent electrode 7' is formed on the polarizing plate (insulating plate) 5, and a spacer 6 is provided. Thereafter, a polarizing plate 5' is provided on the substrate 1', and the laminated portion in which the transparent electrodes 2'' are laminated is stacked together with the injection of the liquid crystal layer portion 7 to confine the liquid crystal, thereby forming a laminated type FE-TN type cell. was configured.

First, external light as shown by the arrow is incident on the laminated cell, but the FE-TNN Miko? Apply a voltage change of 11 (to form a dark area at an arbitrary position (61 =
L<+>. Next, the light resistance of the photoconductive material layer 4 is lowered according to the dark area to form a low resistance area 4' (FIG. 7).
. The photoconductive material layer and the electrochromic coloring layer contain i.
i'E-'II'N Different from the element drive circuit, a C0 electric field is applied, and a photocurrent is caused to flow to the counter electrode 2 by lowering the resistance value of the photoconductive layer according to the amount of external light, and the process I/retrochromy is performed. Develops color in the coloring layer.

Of course, in this case, a structure is adopted to avoid coloring (fogging) of the electrochromic layer due to unnecessary light for display, and after coloring, the voltage applied to the layer is removed.

In FIG. 8, a colored area 6 and an uncolored area 3 are shown, forming a colored contrast pattern.

Since FIGS. 6 to 8 are schematic diagrams for explaining the operation, details are omitted. After color development, even if the position of the dark part of the FE-TN element part is changed due to a change in the applied voltage, an electrochromic colored part and an uncolored part are formed in the electrochromic coloring layer relative to the dark part.

Therefore, the liquid crystal dark area display section 10 designated by the liquid crystal display section is stored.

However, as shown in FIG. 9, it is possible to observe and display the sequential information formed by moving the liquid crystal dark area display section 10 in the direction of the arrow in comparison with the light-memory material coloring section 6'. It is.

A feature of the present invention is that it is possible to display various colors by coloring the electrochromic coloring layer.

For example, by selecting an electrochromic substance, it is possible to display dark blue, blue, green, or orange.

Further, since a feature of the liquid crystal used in the present invention is that it is also capable of color display, multicolor display of two or more colors is possible.

Furthermore, although the memory portion of the electrochromic coloring layer is maintained without the application of voltage, it can be immediately erased by applying a reversing electric field to the layer using a circuit as shown in FIG.

Furthermore, if the electrochromic coloring layer is formed in a part of the liquid crystal display section as shown in FIG. 11, partial memory and partial memory coloring display becomes possible.

Application examples of the display element of the present invention include data memory display in meter sections of various measuring instruments, information display in the viewfinder of cameras, and power meters that compare front and rear outputs. Specific examples of variations are shown in FIGS. 12 to 16. FIG. 12 shows an example of application to a measuring instrument, and FIG. 16 shows an example of application to a camera.

Compared to various conventional displays, the display can be displayed in color with greater contrast, thereby reducing errors in reading instructions and significantly reducing fatigue on the part of the observer or user. In this example, an electrochromic substance was described, but the same applies to the case where other memorizing and coloring substances are used.

According to the present invention, it is possible to omit the step of attaching a polarizing plate when manufacturing a conventional liquid crystal display element, so it is possible to improve the yield during manufacturing of a liquid crystal display element, and to reduce the thickness of the display element. However, it has the advantage of preventing double images from occurring.

[Brief explanation of the drawing]

Figures 1 to 4 are the basic configuration and illustrations by uJ regarding the display method of the liquid crystal cell used in the present invention, and Figures 5 to 8.
The figures are a basic configuration diagram, a sectional view, and a schematic diagram for explaining the operation of a display element according to the present invention. FIGS. 9 to 13 are schematic explanatory diagrams showing display forms and examples of the display element of the present invention. 1...Substrate 2, 2', 2", 2"...Transparent t
i-pole 3... Photo-memory material layer 6'... Photo-memory material coloring part 4... Photoconductive material layer 4'... Low-resistance photoconductive material layer 5, 5'--Unipolar element 4 counters 6@・Φ spacer 7...Liquid crystal layer 8...Power supply 9・Fist-variable resistor 10...Liquid crystal dark display section Applicant Canon Co., Ltd. A//'1 105-

Claims (1)

[Claims] 6 MTs on the rJL electrode plate having electrodes on the polarizing plate;
A liquid crystal display element characterized in that a liquid crystal is sandwiched between electrode plates having electrodes facing opposite poles.