JPH01929A - liquid crystal display element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a liquid crystal display element, and more specifically, the present invention relates to a liquid crystal display element in which a liquid crystal is driven only on a transparent conductive layer formed on one of a pair of transparent substrates.
Fi pressure is applied to drive the liquid crystal display element.

[Prior Art 1] Conventionally, a liquid crystal display element to which a voltage can be applied from one transparent substrate side of the liquid crystal display element has been provided.

FIG. 7 is a schematic cross-sectional view of a conventionally provided liquid crystal display element. As shown in FIG. 7, a conventional liquid crystal display element has a pair of transparent substrates 1a facing each other.

1b, transparent conductive layers 2a and 2b formed on the surfaces of the transparent substrates 1a and 1b, respectively, and the transparent conductive layer 2a.

alignment films 3a and 3b formed on the surfaces of 2b, a liquid crystal material 4 sealed in gaps provided by spacers (not shown) in the alignments 113a and 3b121, a transparent substrate 1a,
It has adhesive parts 5a and 5b for fixing the lb, and a transfer 6 provided in the adhesive part 5a.

The above transparent S-den 1i! 2b are mutually insulated and divided in the region of the adhesive portion 5a, and one of the divided parts is connected to the other transparent conductive layer 2a via the transfer 6. Therefore, the transparent conductor 112 is
By applying voltages of different polarities to both ends of b, the liquid crystal is driven.

[Problems to be solved by the invention] However, in the above liquid crystal display element, the transfer 6
In order to form this, it is necessary to align the transparent conductive layer 2a%2b and the transfer with high precision.

Therefore, by providing two or more transfers, defects caused by misalignment of the transfers can be prevented.

However, providing a transfer increases the area of a portion unrelated to display in a liquid crystal display element. Furthermore, it is difficult to completely prevent conduction defects caused by transfer defects.

The present invention was devised in view of the above-mentioned circumstances, and aims to provide a liquid crystal display element that can apply a g-force voltage from one transparent substrate side by simple construction without providing a transfer or the like. It is something to do.

[Means for Solving the Problems] The liquid crystal display element according to the present invention includes a pair of transparent substrates arranged to face each other, a transparent conductive 2I layer formed on the surface of the transparent substrates, and a transparent conductive layer formed on the surface of the transparent substrates. a liquid crystal material sealed in the gap between the transparent substrates, wherein a voltage application terminal is disposed only on one of the transparent conductive layers on the entrance surface of the pair of transparent substrates, and The conductive layer is characterized by having two regions that are electrically insulated from each other with a predetermined gap and to which a predetermined potential difference is applied.

[Function] A voltage is applied from the outside to one of the opposing transparent conductive layers of the liquid crystal display element via a voltage application terminal, and no voltage is applied from the outside to the other one.

Further, one side to which a voltage is applied has two regions to which a predetermined voltage is applied.

In the transparent conductive layer on the other side facing each of the two regions, charges having a polarity opposite to those appearing in each region due to the application of voltage to the two regions are induced by static MAR conduction. Ru. Due to such electrostatic induction, the opposing transparent conductors [11
A voltage is applied to the liquid crystal material between the two.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

(First Example) The first example is a case where the present invention is applied to a liquid crystal anti-glare mirror.

FIG. 1 is a schematic cross-sectional view of a liquid crystal anti-glare mirror according to a first embodiment.

As shown in Fig. 1, the liquid crystal anti-glare mirror according to this embodiment is as follows:
Transparent glass substrates 1a and ib, transparent conductive layers 2a and 2b respectively formed on the inner surface of the glass substrate, and transparent conductive layer 12a.
A transparent conductive W12a is formed at a bonding portion for bonding alignment films 3a and 3b formed on the surfaces of W12b, a liquid crystal material 4 sealed in a gap provided via a spacer (not shown), and a transparent substrate 1a11b facing each other. An explanatory diagram showing the shape of
FIG. 3 is an explanatory diagram showing the shape of the transparent conductive layer 2b.

The method for manufacturing and operating the liquid crystal anti-glare mirror will be described below.

First, a pair of transparent glasses (for example, alkali-free glass) were prepared and used as transparent substrates. On the surface of one transparent substrate 18, TTO (1n t 003-8n
o) A film was formed on almost the entire surface. Further, as shown in FIG. 3, the other transparent substrate 1b is provided with two areas 21 and 22 that are equally divided by providing a predetermined interval in the center, and the voltage applied to one area 21 is An application terminal 210 and a voltage application terminal 220 for applying voltage to the other region 22 were formed.

In addition, the TTO film is made by sputtering at a temperature of 400A to 100A.
It was formed with a film thickness of 0.

Next, polyimide is applied to the inside of each transparent conductor 112a, 2b and subjected to a rubbing treatment to achieve orientation M! 13a 13b
Formed.

Such transparent substrates 1a and 1b were placed parallel to each other, a gap was provided by a spacer (not shown), and their side edges were adhesively fixed with a sealant. The sample was placed in a vacuum device, the gap formed by the spacer was evacuated, the side surface of the opening was immersed in the liquid crystal, and the liquid crystal material 4 penetrated into the gap d between both substrates.

Here, the gap formed by the spacer (not shown) is
It is approximately 10 μm. In addition, the liquid crystal material 4 includes a nematic liquid crystal with positive dielectric anisotropy, a chiral nematic liquid crystal, and 2
Added color pigment. That is, it attempts to utilize the so-called phase transition effect. In this example, the above-mentioned liquid crystal material was used, but other liquid crystal materials may be used, such as those exhibiting a dynamic scattering effect (DSM liquid crystal).

Further, the reflecting plate 60 was formed by vacuum-depositing Ag or the like on the outer surface of the transparent substrate 1b.

When the liquid crystal anti-glare mirror is not anti-glare, an alternating current voltage is applied through voltage application terminals 210 and 220. At this time, in the transparent conductive layer 2a, a charge having a polarity opposite to that of the voltage applied to the regions 21 and 22 is induced by electrostatic induction in a portion corresponding to the opposing surfaces of the two regions 21 and 22 of the transparent conductive layer 2b, and the liquid crystal An electric field is applied to the material 4. In this case, the voltage threshold required to drive the liquid crystal is twice that of the conventional combination in which voltages of different polarities are directly applied to opposing transparent ffi poles.

That is, the voltage applied between the transparent conductive layer 2a and one region 21 of the transparent conductive R layer 2b is V+[V], and the capacitance between the transparent conductive layers 2a and 21 is G+[μF]. Also, transparent conductivity 1! ! 2a and the other region 22 of the transparent conductive layer 2b
If the voltage applied between them is V2 [V] and the capacitance between the transparent conductive layers 2a- and 22 is 02 [μF], then the voltage V applied between the voltage application terminals 210 and 220 is [
This is because, as shown in FIG. 4, if S I ``F S t, then C+ C will be attacked and ', V I-V t- ~ V ko.

Also, the distance between the two regions FIA 21 and 22 of the transparent conductive Fi layer 2b is 1> compared to the gap d in which the liquid crystal 4 is sealed.
Must be 2d. If z>2d, then
This is because the strength of the electric field between the two regions becomes greater than the strength of the electric field between the opposing conductive layers, and the alignment of liquid crystal molecules in the centrally divided portion becomes different from that in other portions. or,
If the above-mentioned interval nu is made too large, there will be a portion in the center that does not operate. Therefore, in the case of this embodiment, since the gap d is 10 μm, it is desirable that the interval nu be 20 to 100 μm, more preferably 30 to 50 μm.

In this way, a predetermined AC voltage is applied to the voltage application terminal 210.
．． 220, the helical structure of the cholesteric phase of the host liquid crystal of the liquid crystal material 4 is unraveled, and the phase transitions to a nematic phase with a homeotropic alignment aligned in the direction of the electric field. Furthermore, the molecular axis of the dichroic dye is also aligned in the direction of the electric field as the molecular axis of the liquid crystal matrix moves. Since the incident light travels in the direction of the electric field, no light absorption occurs. Therefore, when a voltage is applied, the liquid crystal layer becomes transparent, and the anti-glare state becomes non-glare.

Next, when the application of AC voltage to the voltage application terminals 210 and 220 is stopped, the liquid crystal matrix of the liquid crystal material 4 becomes a planar arrangement in which the helical axis is perpendicular to the substrate, so that the incident light is The light is absorbed by the dichroic dye arranged along with the liquid crystal matrix, and the reflecting mirror becomes anti-glare.

(Second Example) The second example uses a liquid crystal display element that uses
This is a case where segment display is performed, and the first
This example differs from the example in the pattern formation of the transparent conductive layer and the voltage application method. The other points are the same as those in the first embodiment, so the explanation will be omitted. Figures 5 and 6 show transparent grooves formed on the surface of a transparent substrate in the second embodiment.
FIG. 3 is an explanatory diagram showing the shape of Wl. The transparent groove 'Kij112a formed on one surface of the transparent substrate is formed substantially over the entire transparent substrate 11a, as shown in FIG.

Further, the transparent conductive IW 12b formed on the surface of the other side 11b of the transparent substrate includes the segment portion 31 formed in the shape of a “Japanese character” and the common region W5 forming the peripheral region thereof.
38, and each of these areas has a voltage application terminal 31
Voltages of different polarities are applied through 0 and 380C. Further, the voltage application terminal 310 is composed of eight voltage application terminals corresponding to each segment, and a voltage is applied according to the display content by static drive or multiplex drive.

Here, in order to drive only the liquid crystal corresponding to the segment section 31, it is necessary to satisfy the following conditions.

That is, SC: total area of the common area SS: total area of the segment VC = magnitude of voltage applied to the liquid crystal layer corresponding to the common area S: voltage applied to the liquid crystal layer corresponding to the segment Vth: Threshold voltage level for driving the liquid crystal ■: When SC>SS in the potential difference of the applied voltage between the voltage application terminals 310 and 380, (SC, 86>O) In order to drive the liquid crystals of the portions corresponding to the segment section 31 and the common fElli section 38 together, Vs>Vc
>Vt h The above liquid crystal display element has a circumferential gap of 10 μm between the transparent substrates.
The width of the lead line is 1 μm, and the interval between the lead lines is 3
The distance between the μm1 common area portion 38 and the segment portion 31 was set to 20 μm.

Under these conditions, a liquid crystal display element was manufactured in the same manner as in the first example, and when the segment type liquid crystal display element was driven, the lead lines were hardly visible and a uniform display was obtained.

[Effects of the Invention] As described in E, according to the present invention, a transparent electrode can be applied to one of the transparent conductive WI layers formed on the surfaces of a pair of transparent substrates without requiring a voltage application unit such as a transfer. A liquid crystal display element to which voltage can be applied only from one side can be provided.

Therefore, the process can be simplified compared to the conventional case where transfer formation is required. Further, it is possible to prevent the display area from being restricted due to transfer formation and from reducing the yield.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a liquid crystal anti-glare mirror according to a first embodiment. FIG. 2 is an explanatory diagram showing the shape of one transparent conductive layer W1 of the liquid crystal anti-glare mirror according to the first embodiment. FIG. 3 is an explanatory diagram showing the shape of the other transparent groove WIWI of the liquid crystal anti-glare mirror according to the first embodiment. FIG. 4 is an explanatory diagram illustrating the level of voltage applied between the transparent conductive layers 2a12b of the liquid crystal anti-glare mirror according to the first embodiment. FIG. 5 is an explanatory diagram of one transparent groove 'RH of the segment type liquid crystal display element according to the second embodiment. FIG. 6 is an explanatory diagram of the other transparent conductive layer of the segmented liquid crystal display element according to the second embodiment. FIG. 7 is a schematic cross-sectional view of a liquid crystal display element according to the prior art. 1a11b...Transparent substrates 2a, 2b...Transparent conductive layers 3a, 3b...Alignment film 4...Liquid crystal material patent applicant Toyota Motor Corporation

Claims (4)

[Claims] (1) A liquid crystal display comprising a pair of transparent substrates arranged to face each other, a transparent conductive layer formed on the surface of the transparent substrates, and a liquid crystal material sealed in the gap between the pair of transparent substrates. In the element, a voltage application terminal is disposed only on one of the transparent conductive layers on the surface of the pair of transparent substrates, and the one transparent conductive layer is electrically insulated from each other with a predetermined gap and has a predetermined potential difference. A liquid crystal display element characterized in that it has two regions to which is provided. (2) The liquid crystal display element according to claim 1, wherein the two regions are formed by symmetrically dividing a transparent conductive layer at the center. (3) The two regions are regions forming a predetermined pattern;
The liquid crystal display element according to claim 1, which is a region forming a peripheral portion of the region. (4) The liquid crystal display element according to claim 1, wherein the gap between the two regions of the transparent conductive layer is at least twice the gap in which the liquid crystal material is sealed.