JPH01178927A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To compensate a deficiency in the performance of a liquid crystal material and to obtain high contrast even when liquid crystal with a small tilt angle is used by laminating two liquid crystal layers. CONSTITUTION:There are two sheets of liquid crystal cells 10A and 10B between a couple of polarizing plates 2 and 3 and an intermediate polarizing plate 4 similar to the polarizing plates 2 and 3 is interposed between those liquid crystal cells 10A and 10B. Those two sheets of liquid crystal cells 10A and 10B are constituted almost similarly and the liquid crystal cell 10A is constituted by forming a matrix of a liquid crystal layer 13A sandwiched at intersections of electrodes 14A and 15A as picture elements so that an image can be displayed. The orientation direction of the liquid crystal layer 13A is set at an angle psi clockwise from the axis of polarization of the polarizing plate 2 and this angle psi is limited to 45 deg.-theta, where theta is the tilt angle of the ferroelectric high polymer liquid crystal of the liquid crystal layer 13A. Consequently, optical characteristics of each liquid crystal layer are cumulated to make an extremely sharp display even when a liquid crystal material which has a small tilt angle thetais used.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a display element that performs display using a liquid crystal whose optical characteristics change in response to an electric field, and is used in displays such as portable televisions and small-sized displays. It can be used as a display device for measuring equipment.

[Conventional technology]

Conventionally, display elements using liquid crystals have been widely used in display parts of portable devices because they can be made thin and lightweight.

Such a liquid crystal display element has a structure in which, for example, a liquid crystal layer is sealed between a pair of glass substrates having thin electrode films on their surfaces to form a liquid crystal cell, and this liquid crystal cell is sandwiched between a pair of polarizing plates. , the polarization axis (amplitude direction) of light transmitted through the liquid crystal layer is changed by the liquid crystal molecules, and
Taking advantage of the fact that the alignment direction of liquid crystal molecules can be controlled according to the voltage applied to the electrodes, the polarization axis of light from one of the polarizing plates is set in a direction in which it can or cannot pass through the other polarizing plate. By switching and intermittent transmitted light, a display that is visible from the outside is realized.

Here, as the above-mentioned liquid crystal display element, conventionally, TN (twisted nematic) type liquid crystal element and 5TN (
Super TN) type liquid crystal elements are known, but in recent years, ferroelectric liquid crystals, which are advantageous in terms of constraint response and high contrast, have attracted attention.

[Problem that the invention seeks to solve]

However, in liquid crystal display elements using such ferroelectric liquid crystals, the polarization axis is rotated using birefringence, so if the tilt angle during operation is small due to the basic performance of the liquid crystal material used, However, when it is difficult to obtain high contrast or the response speed is low, it is impossible to use it as an image display, and there are major restrictions due to the lack of performance of the liquid crystal material.

Furthermore, depending on the liquid crystal material, the operating temperature range is narrow, making it difficult to consistently obtain good contrast or response speed from low to high temperatures, such as when used outdoors.
There has been a desire for a liquid crystal display element that can overcome these limitations of liquid crystal materials.

An object of the present invention is to provide a liquid crystal display element that can provide high display contrast and quick response speed regardless of the performance of the ferroelectric liquid crystal, and can perform display operations over a wide temperature range.

[Means for solving problems]

In the present invention, a liquid crystal display element is constructed by providing a plurality of liquid crystal layers sandwiched by electrodes between a pair of polarizing plates, and also interposing a polarizing plate between each of these liquid crystal layers.

Here, as the ferroelectric liquid crystal used in the present invention, for example, DOBAMBC (p-decyloxybenzylidene p°
In addition to low-molecular ferroelectric liquid crystals such as (amino 2-methylbutyl cinnamate), ferroelectric polymer liquid crystals such as polyacrylate-based, polyether-based, polysiloxane-based, polyester-based, etc. can be used. Copolymers containing repeating units in each prefecture or other molecular weight 1
Polymer liquid crystal having a molecular weight of 000 or more is suitable.

[Effect]

In a liquid crystal display element having such a configuration, the optical axis of the ferroelectric liquid crystal molecules in each liquid crystal layer is aligned in a specific direction in response to changes in the electric field caused by voltage application to the electrodes, and the polarization axis of the liquid crystal layer is adjusted. Display is performed by intermittent transmission of light between the polarizing plates depending on the change. At this time, if the tilt angle of the liquid crystal material used for each liquid crystal layer is small and insufficient for display, by stacking multiple liquid crystal layers, the lack of contrast in each layer is compensated for, achieving sufficient contrast as a whole, and each layer The small tilt angle of the liquid crystal material is effectively utilized to achieve high-speed response as an element.

In addition, by using different ferroelectric liquid crystals in multiple liquid crystal layers, the temperature characteristics and optical characteristics of each liquid crystal layer are mutually complementary, expanding the temperature range in which the device can operate, improving contrast, and suppressing hue changes. The present invention achieves the above object by compensating for the lack of performance of the liquid crystal material.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

1 and 2 show a liquid crystal display element 1 according to the present invention.
An example of this is shown, and this liquid crystal display element 1 has two liquid crystal cells 10A and IOB between a pair of polarizing plates 2.3, and these liquid crystal cells IOA.

An intermediate polarizing plate 4 similar to the polarizing plate 2.3 is also provided between 10B and 10B.
is interposed.

As shown in FIG. 3, these polarizing plates 2, 3.4 are arranged so that their respective polarizing axes 2A, 3A, 4A are sequentially rotated counterclockwise by 90°, and as a result, the polarizing axes 2A, 3.4, 3A
and polarization axis 4A are orthogonal to each other (crossed Nicols)
It is said that

Returning to FIGS. 1 and 2, two liquid crystal cells 10A,
The IOBs have almost the same structure, and the liquid crystal cell IOA has a transparent substrate 11 made of a thin plate of glass or the like.
A liquid crystal layer 13A made of an alignment film of ferroelectric polymer liquid crystal is sandwiched between A and 12A.

Striped electrodes 14A, 15A are arranged in parallel on the surfaces of these substrates 11A, 12A, and these electrodes 14A, 15A are arranged orthogonally to each other to form a lattice shape, and the liquid crystal cell IOA and IOB are electrode 1
The liquid crystal layer 13A sandwiched at each intersection of 4A and 15A forms a matrix in which pixels are used to display an image.

Here, the electrodes 14A and 15A are formed by forming a transparent and conductive thin film (■Tol layer) of indium oxide (1-gos) mixed with a trace amount of tin oxide (S-01) by sputtering, etc., and by etching, etc. It is divided into stripes and shaped into stripes.

In addition, when forming the alignment film of the liquid crystal Jllil 3A, for example, the electrode 14 is placed on the surface of one substrate 11A.
From above A, a ferroelectric polymer liquid crystal with a molecular weight of 1000 or more is fully oriented by a coating method or a stretching method, etc.
It is formed into a film by coating to a suitable thickness of about 4 μm.

In addition, as shown in FIG. 3, the alignment direction 16A of the liquid crystal layer 13A
are arranged to form an angle ψ counterclockwise from the polarization axis 2A of the polarizing plate 2, and this angle ψ is 45@-θ, where θ is the tilt angle of the ferroelectric polymer liquid crystal of the liquid crystal layer 13A. is set to .

On the other hand, the liquid crystal cell IOB is configured in substantially the same manner as the liquid crystal cell IOA described above, and has substrates 11B and 12B, and a liquid crystal 71, respectively.
! 13B, and electrodes 14B and 15B, as shown in FIG.
Angle ψ (=45° - θ) counterclockwise from the polarization axis 4A of
It is arranged so that it forms.

In such a configuration, a polarizing plate 2 is provided on the liquid crystal display element 1.
Illumination light 20 is applied from the side, and the liquid crystal cells IOA and IO are
The birefringence characteristics of the liquid crystal layers 13A and 13B are changed by applying a display voltage (2) to each of B, and the transmitted light 21 passing toward the polarizing plate 3 is interrupted for each pixel, thereby creating a predetermined pattern of brightness and darkness. Image display is performed using .

That is, electrodes 14A, 14B and electrode 15A.

When a display signal voltage +■ is applied between the liquid crystal layers 15B and 15B, as shown in FIG.
, 16B counterclockwise by an inclination angle θ and maintained at ψ10=45°.

Therefore, the polarization axis 2 of the illumination light 20 incident from the polarizing plate 2
The polarization axis of the A-direction component 22 is rotated in the polarization axis 4A direction by birefringence in the liquid crystal cell IOA, and the polarization axis 4A direction component 23 that has passed through the polarizing plate 4 is similarly rotated in the liquid crystal cell 10B.
The light is rotated in the direction of the polarization axis 3A while passing through the polarizing plate 3 to generate transmitted light 21.

On the other hand, when the polarity is reversed and the display signal voltage -■ is applied, the electric dipole moment of the liquid crystals Fi13A and 13B is 17
C and 17D are each rotated clockwise by 2θ and maintained at 45°-2θ from the polarization axes 4A and 3A, respectively. Therefore, the polarization axis 2A direction component 22 of the illumination light 20 decreases in the polarization axis 4A direction component 24 from the liquid crystal layer 13A, and the amount of light passing through the polarizing plate 4 is insufficient, and the polarization axis 3A direction component from the liquid crystal layer 13B decreases. Since the component also decreases, the transmitted light 25 passing through the polarizing plate 3 is substantially blocked and is not visually recognized, and the pixel becomes dark.

The transmitted light 21 that is intermittent in this manner changes depending on the orientation angle ψ of each liquid crystal 1i13A, 13B of the liquid crystal display element 1, and FIG. Shown for each display state. In FIG. 4, the tilt angle θ of the ferroelectric polymer liquid crystal used in the liquid crystal layers 13A and 13B is set to 11.25°, and the horizontal axis represents ψ+θ, that is, the polarization direction φ+θ in the bright state.

Here, in the bright state of the display signal voltage +■, as shown by the solid line in the figure, it changes periodically around 11 shown by the dotted line in the figure, and the transmitted light intensity at ψ+θ=45° in this example is L+Ii
It is. In addition, in the dark state with the display signal voltage -■, the two layers are shifted by 2θ by 4θ as shown by the two-dot chain line in the figure, and the transmitted light intensity is 1. -11, so the contrast is.

By the way, if the liquid crystal layer is one layer, there is no deviation in the dark state like -V' by 2θ, and the transmitted light intensity is 11
And the contrast is ■! becomes.

Therefore, by setting the liquid crystal layer to 2N as in this embodiment, the contrast is improved by the ratio CRz It CR+ It It. This means that the tilt angle θ is 22°
It is effective in compensating the performance of liquid crystal materials having a small value such as the following, and by increasing the orientation of the liquid crystal layers 13A and 13B, ll-12 can be further reduced and the contrast improvement property can be further enhanced.

In this way, according to this example, by having a plurality of liquid crystal layers, the optical characteristics of each liquid crystal layer are accumulated, and even if a liquid crystal material with a small tilt angle θ is used for each liquid crystal layer, high contrast can be obtained. It is possible to obtain high visibility due to extremely clear display.

In addition, since sufficient contrast can be obtained even with a liquid crystal with a small tilt angle θ, it is possible to reduce the tilt angle θ to increase the operating speed of each liquid crystal molecule, thereby increasing the response speed of the liquid crystal display element 1. is also possible.

Furthermore, even if a liquid crystal material whose temperature characteristics are not compatible with the environment in which it is used and which cannot fully exhibit its optical characteristics is used, it is possible to compensate for temperature changes in contrast with the configuration of this embodiment.

In the above embodiment, the orientation angle ψ of the liquid crystal layers 13A and 13B was set to 45°-θ, but the angle ψ was set to 45°+
It may be set to θ, in which case the bright and dark display states are reversed. By the way, the reason for setting the orientation angle ψ to 45°±θ is to maximize the brightness in the bright state of the display.If you want to ensure extinction in the dark state, the orientation angle ψ is set to 45°±θ. Just set it.

In addition, the polarizing plate 4 between the liquid crystal layers 13A and 13B aligns the polarizing axis 4A with the polarizing axes 2A and 3A, and aligns the polarizing axis 4A with the polarizing axis 2A and 3A.
A and 4A may be arranged in parallel (parallel Nicol), and the orientation direction 16B of the liquid crystal layer 13B is aligned with the polarization of the polarization axis 4A.
Since the liquid crystal cell 10A and the IOB are aligned in the alignment direction 16A of the liquid crystal layer 13A, the liquid crystal cell 10A and IOB can be shared. At this time,
Although the bright and dark display conditions are reversed, you can change the orientation direction 1 as necessary.
Set 6A, 16B, for example, voltage +V for bright state.
The brightness of the bright state can be maximized by setting the orientation angle ψ=θ so that the electric dipole moments 17A, 17B upon application are completely offset by the polarization axes 2A, 3A, 4A.

Furthermore, in the embodiment, 2N of the liquid crystal layers 13A and 13B
However, two or more liquid crystal layers may be provided between the polarizing plates 2 and 3, and if a plurality of liquid crystal layers and polarizing plates are alternately laminated, the above-mentioned contrast improvement property can be improved as the number of laminated layers increases. can be further increased, and sufficient optical characteristics can be obtained even if a liquid crystal with a small tilt angle θ or a liquid crystal with an inappropriate temperature range is used.

Also, LCD J! ! The ferroelectric liquid crystals used for 13A and 13B are not limited to ferroelectric polymer liquid crystals, but may also be low-molecular ones. Methods for aligning these ferroelectric liquid crystals include rubbing, orthorhombic. There are vapor deposition methods, shearing methods, etc.

However, when using polymeric liquid crystals, stretching methods and coating methods that take advantage of their properties can be applied, and among them, stretching methods and coating methods are suitable for forming thin films of ferroelectric polymeric liquid crystals.
By appropriately setting the stretching direction or the coating direction when forming the liquid crystal layers 13A and 13B, a predetermined alignment process can be performed very easily.

In addition, each of the liquid crystals 113A and 13B has a thickness of 0.5
The thickness may be approximately 20 μm, and may be set as appropriate depending on the required optical characteristics. Although there is no problem even if the thickness is even thicker, the thickness may be approximately 0.0 μm because it provides bistability and reduces the applied voltage. ．． It is preferable that the thickness be about 5 to 4 μm.

Furthermore, a spherical or fibrous spacer made of silicon dioxide (SiOz), ceramics, plastic, or the like may be used in combination with the liquid crystal layers 13A and 13B, if necessary.

Also, the substrates 11A, IIB, 12A, 12B.

As the substrate, glass, polyethylene terephthalate, polymethyl methacrylate, polycarbonate, and other plastics can be used. In particular, by using flexible or thin plastic as the substrate, the ferroelectric polymer liquid crystal itself can be used. Since it is flexible, the liquid crystal display element 1 can be made bendable.

Furthermore, the first and second electrodes 12.16 and the intermediate electrode 1
6. Finally, the ITO film is made of tin oxide (S-OX).
), metal oxide films such as tin oxide film called NESAM, or metal thin films such as gold (A), aluminum (AI), titanium (Ti), etc. In its formation, not only sputtering but also direct vapor deposition, spraying, etc. may be used (in short, it is desirable to form a transparent and conductive thin film that does not impede the transmission of light.

Further, the electrodes 14A, 14B, 15A, and 15B are arranged on each side in parallel with a plurality of striped electrodes in a direction that intersects with each other, forming a matrix with pixels at the intersections, so that an image can be displayed. Not limited to, for example,
When used for a bar graph or the like, each of the electrodes 15A and 15B may be used as a common electrode, and when only a specific pattern is to be displayed, each electrode may be formed into a planar shape.

Next, among the liquid crystals used in the present invention, ferroelectric polymer liquid crystals will be explained.

The ferroelectric polymer liquid crystal used in the present invention is not particularly limited and various types can be used, but usually, a polymer compound having a mesogen in a side chain with a spacer interposed therebetween can be suitably used.

This side-chain polymer liquid crystal is composed of three parts: a polymer main chain, a mesogen, and a spacer.
Examples include those represented by the following general formula (1).

1+Eh-+E'+T (1) Old Mu However, in formula (1), →E+-r-+E' is the polymer main chain, D is a spacer, and '+M is a mesogen. b may be 0. If b is not 0, the units of (E-D-M) and (E゛) in the formula may be combined randomly even if they are combined in blocks. They may be combined alternately.

As the main chain, main chains of various polymers can be used, and preferred main chains include polyacrylate, polysiloxane, polyether, polyester, polymethacrylate, and the like.

Although various types of spacers can be used as the spacer D, for example, one represented by the following formula (2) can be cited as a suitable one.

→COO+-T-fCHzh (2) However, in formula (2), m represents 0 or 1, and n represents an integer from 1 to 30.

Although various mesogens can be used as the mesogen M, for example, one represented by the following formula (3) can be preferably used.

→Z))-T, (3) However, (
3) In the formula, 2 represents 0 or 1, Z represents 0 (oxygen atom) or -Coo- (ester bond), and T1 represents the following (4)
Those represented by the following formulas can be preferably used.

■X Gin R! , ()X e R.

ex■XginR・.

琵X唟X文R1(4) However, in each formula (4) above, X is, for example, -COO-1-
Represents OCO-, and R2 is, for example, -COOR3, -0C
represents ORs, -0Rs, -CORs, -R3,
-R1 represents a chain or branched alkyl group, haloalkyl group, or cyanoalkyl group having 4 to 10 carbon atoms and containing one or more asymmetric carbon atoms.

Among these polymer liquid crystals, chiral smectic C phase (S
, C'' phase) is preferred.

Examples of ferroelectric polymer liquid crystals having such a chiral smectic C phase include the following polymer liquid crystals (13 to (V)).
The polymeric liquid crystal V) usually has a chisyl smectic C phase in the temperature range from room temperature to around 150°C, and is extremely excellent in response speed, contrast, and film formability.

(1) Polyacrylate polymer liquid crystal (patent application 1986-3)
No. 05251 and Japanese Patent Application No. 106353/1982 filed by the present applicant, etc.) Polyacrylate polymers and their copolymers having repeating units of the following general formula → CHffi-CH← COO → CHz h-Z -RI where k is an integer from 1 to 30, preferably from 4 to 20
is an integer of , Z is -o-, -coo-, X is -coo-, -oco-, and Rt is -COO
Rs, -0CORs, -0R1, or -R8,
Here R3 can be represented, where R,,R, is -C
H3, -CN, -F or CI, preferably 10H
, and g and h are integers from O to 10, q is O or 1, and C1 is an asymmetric carbon atom. However, R3
When is -CH, h is not O. Also, R3
A particularly preferred example is (2) -CHtCH-ChH13.

(If) Polyether polymer liquid crystal (Patent application 1986-30)
No. 9466 filed by the present applicant, etc.) Polyether polymers and copolymers thereof having repeating units represented by the following general formula. In the formula, k, R, and R have the same meanings as in the case of the polyacrylate system.

(I [[) Polysiloxane polymer liquid crystal (Patent application 1986-
114716) Polysiloxane-based polymers and their copolymers having repeating units of the following general formula→0-Si← (CHz+T-0-RI In the formula, R4 is lower alkyl k is an integer of 3 to 30, and RI has the same meaning as above.

(IV) Polyester polymer liquid crystal (patent application 1986-20)
No. 6851 filed by the present applicant, etc.) Polyester polymers and copolymers thereof having repeating units consisting of the following general formula, where R7 is H, CHff or CJs, and L is 1 to 20
The integers k and R1 have the same meanings as above.

(V) Polymer liquid crystal in which side chains are fixed to the main chain by hydrogen bonds (this can be inferred from the patent application filed by the present applicant as Japanese Patent Application No. 169288/1983).

The side chain of this substance may be one type or multiple types.

The average molecular weight of the polymer liquid crystal used in the present invention as described in (1) to (V) above is 1,000 to 1゜ooo.
, ooo preferably 1,000 to 400,000
It is. If it is less than 1°000, the moldability of the polymer liquid crystal as a film or coating may be impaired.
On the other hand, if it exceeds 400,000, undesirable results such as slow response speed may occur. A particularly preferable range of the number average molecular weight cannot be unconditionally defined because it depends on the type of substituent, etc., but it is usually 2,000 to 200.
,000.

Note that a plurality of these polymeric liquid crystals may be used in combination as appropriate within the range that does not impede the purpose of the present invention.

The polymer liquid crystal according to the present invention may further include other liquid crystal polymers, olefin resins, acrylic resins, methacrylic resins, polystyrene resins, polyester resins, and polycarbonate resins, within a range that does not impede the purpose of the present invention. ,
It is also possible to create a polymer liquid crystal film by mixing it with ordinary resins such as styrene-butadiene copolymer and vinylidene chloride-acrylonitrile copolymer. However, if a large amount of these resins is added, the liquid crystallinity will deteriorate, so it is preferable that the weight ratio to the polymer liquid crystal is 2 or less.

On the other hand, in order to improve responsiveness, ferroelectric low-molecular liquid crystals such as the above-mentioned DOBAMBC may be mixed and used. The mixing ratio is preferably 5 or less in terms of weight ratio.

There are no particular restrictions on the method of blending the components, and the blending may be carried out by a conventional method.

The ferroelectric polymer liquid crystal used in the present invention is not limited to those having one or two asymmetric carbon atoms at the end of the side chain in the polymer; Those containing 3 or more - can also be used.

Next, specific experimental examples of the liquid crystal display element of the present invention will be explained.

As a first experimental example, we used a low-molecular ferroelectric liquid crystal phase transition behavior with a tilt angle of θ-5° (40°C) as the liquid crystal material of the liquid crystal layer, and rubbed a polyimide-coated glass substrate with an ITO electrode. Then, a liquid crystal layer having a thickness of 2 μm and an alignment direction ψ=45°−θ=40° was formed using a 5ift spacer.

When a display signal voltage of ±5 cm was applied to the liquid crystal display element 1 using two such liquid crystal layers, the contrast was 1O
Met. On the other hand, when there is only one layer, the contrast is about 6, and the contrast improvement rate reaches +60%. In addition, despite this contrast improvement, the response speed (when the sign of the applied voltage is reversed, the transmitted light intensity is 10
% to 90%), high-speed operation was possible as in the general case.

As a second experimental example, we used the aforementioned polyacrylate system as the liquid crystal material, M = 5300, and tilt angle θ = 6'' (
50°C) polymer liquid crystal←CH! Using the C11←C=0 phase transition behavior, a liquid crystal layer with a thickness of 1.5 μm and an orientation direction of φ-45″-〇=39@ was formed on a PET film substrate with an ITO film and an electric film.

Liquid crystal display element 1 using such ferroelectric polymer liquid crystal
As a result of measuring the contrast of the display signal voltage ±IOV
An extremely good value of 22 was obtained by applying . On the other hand, when there is only one liquid crystal layer, the contrast is 15, and when two liquid crystal layers are used, the contrast is +
This is an improvement of about 50%. Furthermore, in this experimental example, since a PET film was used as the substrate, it was possible to bend the entire ferroelectric liquid crystal l.

Therefore, in the liquid crystal display element 1 of the present invention, sufficient contrast can be obtained by doubly laminating the liquid crystal material with a small tilt angle θ, and by compensating for the lack of performance of the liquid crystal material, it is possible to obtain sufficient contrast. The superiority of this type over liquid crystal display elements is obvious.

On the other hand, in the third experimental example shown below, the device configuration is the same as the second experimental example, but different types of liquid crystal materials are used for the two liquid crystal layers.

As the first liquid crystal layer, polyacrylate, M,
-6000 and a tilt angle of θ-5° (130°C), alignment treatment was performed by a coating method using a polymer liquid crystal phase transition behavior.

The second liquid crystal layer has a tilt angle of θ-40° (-20”C
) using the strong y:electroconductive low molecular liquid crystal phase transition behavior, alignment treatment was performed by a rubbing method.

In such a liquid crystal display element 1, by combining 2m class liquid crystals with different temperature ranges, the first liquid crystal layer operates at approximately 60°C to 150°C, and the first
The liquid crystal layers operate at approximately -20°C to 60°C and cover each other's operating temperature ranges, so the combined temperature range is approximately -20°C to 60°C.
In a wide temperature range of 20° C. to 150° C., a good display with a contrast of 17 or higher was obtained by applying a display signal voltage of ±30 V.

Therefore, in the liquid crystal display element 1 of the present invention, by appropriately combining liquid crystal materials with different operating temperature ranges, the operable temperature range can be expanded, and this is also an advantage over the conventional single-layer type liquid crystal display element. The gender is obvious.

〔Effect of the invention〕

As explained above, according to the liquid crystal display element of the present invention, the lack of performance of the liquid crystal material can be compensated for by overlapping the liquid crystal layer into two layers, and high contrast can be obtained even when using liquid crystal with a small tilt angle. In addition, by using different types of liquid crystal materials in each liquid crystal layer, the performance deficiencies of each layer can be compensated for in a mutually complementary manner, and good display can be achieved over a wide temperature range.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing a schematic configuration of an embodiment of the liquid crystal display element of the present invention, FIG. 2 is a sectional view of FIG. 1,
FIG. 3 is a diagram showing the polarization axis of the polarizing plate and the orientation direction of the liquid crystal layer in the embodiment, and FIG. 4 is a graph showing the intensity of transmitted light in the embodiment. 1...Liquid crystal display element, 2,3.4...Polarizing plate and intermediate polarizing plate, IOA, IOB...Liquid crystal cell, 11A. 11B, 12A, 12B... board, 13A, 13B...
...Liquid crystal layer, 14A, 14B, 15A, 15B...electrode.

Claims (1)

[Claims] (1) In a liquid crystal display element comprising a liquid crystal layer of ferroelectric liquid crystal sandwiched between a pair of polarizing plates by a pair of electrodes, a plurality of liquid crystal layers are laminated between the polarizing plates, and a plurality of liquid crystal layers are laminated between the polarizing plates. A liquid crystal display element characterized in that a polarizing plate is interposed between each liquid crystal layer.