JPH10123528A - Display element and production therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display element which has homogeneous layer structures and which displays a high-quality picture. SOLUTION: Rubbings are respectively applied on surfaces of a lower substrate and an upper substrate by once in directions which are parallel with each other and are opposite. A liquid crystal cell is formed by joining the lower substrate and the upper substrate so that the crossing angle between the direction 18A of the orientation processing of the lower substrate and the direction 19A of the orientation processing of the upper substrate becomes 2Φ. The angle Φ is the angle formed by the direction of the orientation and the direction of the normal of the layer of a layer structure which is formed by nearby liquid crystal molecules. Next, liquid crystal 21 is poured into the liquid crystal cell. The normal of the layer of the layer structure of liquid crystal near to the first substrate is the direction 21C inclined with respect to the direction 18A of the orientation by the angle Φ and the normal of the layer of the layer structure of liquid crystal near to the second substrate is the direction 21C inclined with respect to the direction 19A of the orientation by the angle Φ and they coincide each other. As a result, smectic layers growing from the vicinities of both substrates join at almost the center of the thickness direction of the layer of liquid crystal 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device using a liquid crystal having a ferroelectric phase and a method for manufacturing the same.

[0002]

2. Description of the Related Art Instead of a liquid crystal display device using a nematic liquid crystal, which has been widely used, a ferroelectric liquid crystal and an antiferroelectric liquid crystal, which are expected to have a high-speed response characteristic and a wide viewing angle characteristic, are used. Liquid crystal display devices have been developed. As shown in FIG. 11, these liquid crystal display elements are rubbed in parallel to and opposite directions 71A and 72A on opposing surfaces of a pair of substrates 71 and 72 having electrodes formed on opposing inner surfaces, respectively. Liquid crystal or antiferroelectric liquid crystal is interposed.

In order to display a high-quality image in this type of liquid crystal display device, it is desirable that smectic phase liquid crystal be disposed between both substrates while maintaining a uniform layer structure. That is, it is desirable that the structure of the smectic layer due to the alignment of the liquid crystal molecules has few defects.

[0004]

As described above, in the conventional ferroelectric liquid crystal display device and antiferroelectric liquid crystal display device, rubbing is applied to a pair of substrates in parallel and in opposite directions.

However, the liquid crystal of the smectic phase near the substrate is oriented so that the normal of the smectic layer is inclined at a predetermined angle Φ with respect to the direction of the orientation treatment. For this reason,
In the liquid crystal molecules near the upper substrate and the liquid crystal molecules near the lower substrate, the normal direction of the layer having the layer structure is shifted by 2Φ. When a liquid crystal smectic layer is grown from the vicinity of both substrates, the direction of the smectic layer grown from one substrate side and the direction of the smectic layer grown from the other substrate side are at the center of the liquid crystal layer. In some cases, they do not coincide with each other, a break occurs, an alignment failure occurs, and the contrast of a displayed image is reduced, and the quality of the displayed image is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a liquid crystal display device using a smectic phase liquid crystal capable of displaying a high quality image and a method of manufacturing the same. Another object of the present invention is to provide a liquid crystal display device using a smectic phase liquid crystal in which the entire liquid crystal layer has a uniform layer structure, and a method for manufacturing the same.

[0007]

In order to achieve the above object, a display element according to a first aspect of the present invention has an electrode formed on one surface thereof and further having an alignment treatment in a first direction. A first substrate and an electrode are formed on a surface facing the first substrate, and an electrode is formed on a surface facing the one surface, and an orientation process is performed in a second direction having an intersection angle of 2Φ with the first direction. A second substrate is disposed between the first and second substrates, and liquid crystal molecules in the vicinity of the first substrate are oriented in the normal direction of the layer of the layer structure of the liquid crystal of the chiral smectic phase by the first direction. And the liquid crystal molecules in the vicinity of the second substrate are oriented in the normal direction of the layer of the layer structure of the liquid crystal in the chiral smectic phase by the second direction. Oriented in the third direction intersecting at an intersection angle Φ with the direction of And the liquid crystal of Mekutikku phase, more composed.

According to such a configuration, the intersection angle between the direction of the alignment treatment of the first substrate and the second substrate is set to 2Φ, so that the smectic layer (the liquid crystal of the smectic phase is close to the first substrate). Direction of the normal line of the layer having a layer structure)
The directions of the normals of the smectic layer near the second substrate are both the third direction and coincide with each other. Therefore, defects are less likely to occur in the layer structure of the liquid crystal layer, a uniform crystal structure can be obtained, and a high-quality image with few alignment defects can be displayed.

The alignment treatment of the first substrate and the second substrate is performed, for example, by rubbing the surface of an alignment film formed on the substrate a plurality of times in opposite directions.

The liquid crystal is a liquid crystal of S _m CA ^* phase or S _m C ^*.
It is composed of phase liquid crystals.

In order to achieve the above object, a second aspect of the present invention is provided.
The method for manufacturing a display element according to the aspect of the present invention comprises the steps of: performing an alignment process on each of the first and second substrates each having an electrode formed on the opposing surface; and performing the alignment process on the first substrate and the second substrate. Disposing at a predetermined gap such that the intersection angle of the directions is 2Φ; and interposing a normal line of the smectic layer between the first and second substrates in a direction intersecting at an intersection angle Φ with respect to the orientation direction. A step of arranging a liquid crystal of a chiral smectic phase oriented in a direction intersecting at an angle of intersection Φ with respect to the orientation processing direction of a nearby substrate, and heating the liquid crystal once to an isotropic phase, and then A step of reorienting from the vicinity of the first and second substrates.

According to such a configuration, the intersection angle between the direction of the alignment processing of the first substrate and the second substrate is set to 2Φ, so that when the liquid crystal is realigned, the vicinity of the first substrate can be reduced. The direction of the normal of the smectic layer (the layer having the layer structure of the liquid crystal in the smectic phase) and the direction of the normal of the smectic layer near the second substrate are both the third direction and coincide with each other. Accordingly, defects are less likely to occur in the layer structure at the center of the liquid crystal layer, a uniform crystal structure can be obtained, and a high-quality image with few alignment defects can be displayed.

The steps of subjecting the first and second substrates to an alignment treatment include, for example, a step of forming an alignment film on each of the opposing surfaces of the first and second substrates, and a step of: Rubbing a plurality of times in opposite directions.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a display element of this embodiment, and FIG. 2 is a plan view of a transparent substrate on which pixel electrodes and active elements are formed. This display element is of an active matrix type, and as shown in FIG. 1, a pair of transparent substrates (for example, glass substrates) 11 and 12, a liquid crystal 21 disposed between the transparent substrates 11 and 12, and A pair of polarizing plates 23, 2 disposed with the transparent substrates 11, 12 interposed therebetween
4.

In FIG. 1, a lower transparent substrate (hereinafter, referred to as a lower substrate) 11 has a pixel electrode 13 made of a transparent conductive material such as ITO, and a thin film transistor (hereinafter, referred to as a source) connected to the pixel electrode 13. TFTs) 14 are formed in a matrix.

As shown in FIG. 2, a gate line (scanning line) 15 is arranged between rows of the pixel electrodes 13, and a data line (gradation signal line) 16 is arranged between columns of the pixel electrodes 13. The gate electrode of each TFT 14 is connected to a corresponding gate line 15, and the drain electrode is connected to a corresponding data line 16.

The gate line 15 is connected to a row driver 31 and the data line 16 is connected to a column driver 32. The row driver 31 scans the gate line 15 by applying a gate voltage. On the other hand, the column driver 32
Receives the image data (gradation signal) and receives the data line 16
To a data signal corresponding to the image data.

In FIG. 1, an upper (transparent) electrode 12 is formed with an opposing (common) electrode 17 which is opposed to each pixel electrode 13 of a lower substrate 11 and to which a reference voltage is applied. I have. The counter electrode 17 is a transparent electrode formed of, for example, ITO.

Alignment films 18 and 19 are provided on the electrode forming surfaces of the lower substrate 11 and the upper substrate 12, respectively. The alignment films 18 and 19 are horizontal alignment films made of an organic polymer compound such as polyimide. The surface of the alignment film 18 is subjected to an alignment process of rubbing once in a direction parallel to and opposite to each other. The surface of the alignment film 19 is also subjected to an alignment process of rubbing once in parallel and in the opposite direction.

The lower substrate 11 and the upper substrate 12 are adhered to each other at the outer peripheral edge thereof through a frame-shaped sealing material 20 to form a liquid crystal cell 25. The distance between the alignment films 18 and 19 is set to, for example, 1.4 μm by the sealing material 20 and the spacer 22.
m to 2.4 μm, and the liquid crystal 21
Are sealed in a region surrounded by the substrates 11 and 12 and the sealing material 20.

The liquid crystal 21 has a single helical structure (in the case of ferroelectric liquid crystal) or a double helical structure (in the case of antiferroelectric liquid crystal) in a bulk state, and the gap length of the liquid crystal cell is helical. Since it is shorter than the pitch, it is sealed in the liquid crystal cell 25 in a state where the helix is unwound. In the liquid crystal 21, each molecule has a spontaneous polarization PS, and an angle (tilt angle) θ between the cone axis drawn by the molecule and the cone (cone angle) 2 (cone angle) 2
θ is greater than 45 ° (preferably 60 ° or more) chiral smectic C phase or CA phase (SmC ^* or SmC
A ^* ) liquid crystal composition (ferroelectric liquid crystal or antiferroelectric liquid crystal)
Consists of The horizontal component of the director of the liquid crystal 21 (the average orientation direction of the liquid crystal molecules) (the direction projected on a plane parallel to the main surfaces of the substrates 11 and 12) changes continuously according to the applied voltage.

As the liquid crystal having such characteristics, for example, a liquid crystal substance (I) having a skeleton structure represented by Chemical Formula 1
There is an antiferroelectric liquid crystal obtained by mixing (III) at 20% by weight, 40% by weight, and 40% by weight, respectively.

[0023]

Embedded image

It is also possible to use a liquid crystal having a chiral smectic C random phase (S _m C _R ^* ) having no correlation between the tilts of the liquid crystal molecules between the layers having the layer structure of the liquid crystal in the smectic phase.

The threshold value of the electric field induced transition of the antiferroelectric liquid crystal is lowered by introducing an ether bond into the chiral terminal chain of the liquid crystal of the chiral smectic phase, substituting fluorine for the phenyl ring, and blending. A precursor phenomenon in a phase transition with a phase can be remarkable, and a liquid crystal having no clear threshold in its optical characteristics can be generated. In such a liquid crystal, when no electric field is applied, the phase in which the correlation between the layers is lost, that is, the direction of spontaneous polarization in the C-director and the layers is random between the layers and within the layers. On the other hand, when a sufficiently high voltage is applied, the spontaneous polarization is aligned according to the electric field, and the direction is reversed according to the polarity of the applied voltage.

A liquid crystal having such a structure and characteristics is as follows.
For example, it can be obtained by mixing liquid crystals of SmCA ^* and SmC ^* . For example, it can be obtained by mixing the liquid crystal substances I to III having the skeleton structure shown in Chemical Formula 2 at a ratio of 40% by weight, 40% by weight, and 20% by weight, respectively.

[0027]

Embedded image

Next, the relationship between the direction of the alignment treatment applied to the alignment films 18 and 19, the optical axis of the polarizing plates 23 and 24, and the alignment direction of the liquid crystal molecules of the liquid crystal 21 will be described with reference to FIGS. explain.

FIG. 3 shows the alignment direction, the optical axes of the polarizing plates 23 and 24, and the alignment direction of the liquid crystal molecules of the liquid crystal 21 when the liquid crystal display device shown in FIG. FIG. 4 shows the relationship between the direction of the alignment treatment and the normal direction of the layer structure of the liquid crystal molecules of the liquid crystal 21 when the upper substrate and the lower substrate shown in FIG. 1 are viewed from the surface on which the alignment film is formed. FIG.

3 and 4, reference numerals 18A and 19
A indicates the direction of the alignment treatment performed on the alignment films 18 and 19, and both alignment directions 18A and 19A are set to intersect at an intersection angle of 2Φ. As shown in FIGS. 4A and 4B, the liquid crystal 21 near the alignment films 18 and 19 has a layer structure having a layer structure of a chiral smectic C phase (S _m C ^* phase or S _m CA ^* phase). The line is oriented at an angle of Φ ° with respect to the orientation directions 18A, 19A of the orientation process.

The normals of the layers of the layer structure of the liquid crystal 21 near the alignment films 18 and 19 are the directions 18A and 19 that are inclined by Φ ° in opposite directions to the directions 18A and 19A of the alignment treatment.
A becomes the direction 21C of the center line of A.

The tilt angle Φ is generally about 1 ° to 15 °, and the composition of the liquid crystal 21, the material of the alignment films 18 and 19,
It depends on the strength of the alignment treatment and the like. Therefore, the inclination angle Φ is obtained in advance by an experiment or the like, and the directions 18A and 19A of the alignment process are set according to the obtained inclination angle Φ.

For this reason, the liquid crystal 2 near the alignment films 18 and 19
The normal of the layer having the layer structure 1 has a direction 18 of the orientation treatment.
The rubbing directions 18A and 19A are inclined by Φ ° in the opposite directions with respect to A and 19A, respectively.
They match as shown schematically in FIG.

Therefore, the layer structure of the liquid crystal 21 which starts growing near the alignment film 18 and the layer structure which starts growing near the alignment film 19 coincide substantially at the center of the liquid crystal layer. Few.

As described above, when the liquid crystal 21 oriented so as to form a continuous layer structure between the opposing substrates, when a voltage lower than the predetermined negative voltage −VS is applied to the liquid crystal 21, Are oriented substantially in the first direction 21A, and when a voltage higher than the predetermined voltage + VS of positive polarity is applied to the liquid crystal 21, the liquid crystal molecules are oriented substantially in the second direction 21B. When the applied voltage is 0, the average orientation direction of the liquid crystal molecules is substantially the normal direction of the smectic phase layer of the liquid crystal, that is, the direction of 21C.

The deviation angle 2θ between the first direction 21A and the second direction 21B is 45 ° or more, preferably 60 ° or more.

The optical axis (transmission axis in this embodiment) 23A of the polarizing plate 23 is composed of a first direction 21A and an alignment direction 2A.
1C, the direction is set to approximately 22.5 ° with respect to the normal direction 21C of the smectic layer. Polarizing plate 24
Is set in a direction substantially orthogonal to the transmission axis 23A of the polarizing plate 23.

As shown in FIG. 3, a display device in which the transmission axes 23A and 24A of the polarizing plates 23 and 24 are set, transmits light when the average alignment direction of the liquid crystal molecules is set parallel to the transmission axis 23A of the polarizing plate 23. Lowest rate (darkest display)
The average alignment direction of the liquid crystal molecules is determined by the transmission axis 23 of the polarizing plate 23.
The transmittance becomes highest (brightest) when set in a direction 21D at 45 ° to A.

In this liquid crystal element, the transmittance changes when a relatively low frequency (about 0.1 Hz) sawtooth voltage is applied between the pixel electrode 13 and the counter electrode 17, as shown in FIG. It changes continuously and does not show a clear threshold.

Further, since this display element is of the active matrix type, it is possible to maintain a voltage for maintaining the liquid crystal 21 in an arbitrary alignment state even during the non-selection period. Therefore, the display element having the above structure can perform gradation display by changing the transmittance.

Therefore, the row driver 31 sequentially applies a gate pulse to the gate line 15, selects a row of the TFT 14 to which the gate pulse has been applied, and selects a TFT of the selected row.
Turn on 14. On the other hand, the column driver 32 applies a data signal to the data line 15 in synchronization with the gate pulse. A data signal corresponding to a display gradation is applied between the pixel electrode 13 and the counter electrode 17 via the turned-on TFT 14. When the gate pulse turns off, the TFT 14 turns off,
The voltage applied between the pixel electrode 13 and the counter electrode 17 until that time is retained in the pixel capacitance formed by the pixel electrode 13 and the counter electrode 17 and the liquid crystal 21 between them. Therefore, the display gradation corresponding to the holding voltage is held until the next selection period of this row. Therefore, according to this driving method, by controlling the voltage of the data pulse, an arbitrary gradation image can be displayed in accordance with the electro-optical characteristics shown in FIG.

The transmittance of the liquid crystal element is minimum 45 ° when the director of the liquid crystal is parallel to the transmission axis 23A of the polarizing plate 23.
It becomes maximum when crossing at. Therefore, by using the liquid crystal element between the alignment states in which the transmittance is Tmin and Tmax, the liquid crystal 21 can be driven without being aligned in the first and second alignment states that become the ferroelectric phase. In other words, the first and second alignment states are states in which all molecules in the liquid crystal layer exhibit a ferroelectric phase in which the molecules are completely aligned in the same direction. It becomes harder and easier to burn. However, if the liquid crystal molecules are not completely aligned, the charge due to spontaneous polarization hardly accumulates, and the inversion is likely to occur with the non-aligned molecules as nuclei, so that burn-in is reduced. That is, by changing the drive voltage within the range between VTmax and VTmin, the liquid crystal 21 can be driven without using a ferroelectric phase, and further, continuous gradation can be displayed.

Further, since the intersection angle between the directions 18A and 19A of the alignment process is set to 2Φ, alignment defects, particularly discontinuous in the layer structure of the smectic liquid crystal at the center of the layer of the liquid crystal 21 in the thickness direction. A liquid crystal having no uniformity and a uniform layer structure can be obtained.

During the manufacturing process of the liquid crystal element, the liquid crystal 2
If a defect occurs in the first layer structure, the liquid crystal 21 is realigned in the final step. In this case, for example, FIG.
As shown in (A), the liquid crystal cell 25 is connected to the panel heater 6.
1, the liquid crystal 21 is once set to an isotropic phase, and then cooled naturally.

The heat of the liquid crystal cell 25 radiates from its surface, and the temperature of the liquid crystal 21 also decreases from near the substrate. For this reason, as shown in FIG.
The layers are re-oriented from the vicinity of 8 and 19, and the normal line of the layer of the layer structure becomes a direction 21C inclined by Φ ° in the opposite direction from the directions 18A and 19A of the alignment treatment.

Thereafter, as the cooling proceeds, the liquid crystal 21 realigns toward the center between the substrates based on the liquid crystal molecules aligned in the vicinity thereof due to the alignment regulating force of the alignment films 18 and 19. . As shown in FIG. 7C, the smectic layer re-oriented from the alignment film 18 side and the smectic layer re-oriented from the alignment film 19 side are joined at substantially the center between the substrates. Both the layer grown from the side and the layer grown from the alignment film 19 side have the layer normal of the layer structure in the direction of 21C, so that the layer structure at the bonding surface matches, and the continuation of the smectic layer And the liquid crystal 21 with few alignment defects can be obtained.

Next, a method of manufacturing the display element having the above configuration will be described. First, the TFT 14 and the pixel electrode 1 are placed on the lower substrate 11.
3 are formed and an alignment film 18 is further formed. Next, rubbing is performed once on the surface of the alignment film 18 in parallel and in opposite directions. Further, the common electrode 17 is provided on the upper substrate 12.
Is formed, and an alignment film 19 is further formed. Alignment film 19
Is rubbed once in the opposite direction in parallel with each other.

The crossing angle between the direction 18A of the orientation process of the lower substrate 11 and the direction 19A of the orientation process of the upper substrate 12 is set to be twice (2Φ) of the angle Φ previously obtained by experiment or the like. The liquid crystal cell 25 is formed by joining the substrate 11 and the upper substrate 12 via the sealant 20 and the spacer 22. Next, the liquid crystal 21 is injected into the liquid crystal cell 25 using a dispenser method, a dip method, or the like, and after the injection is completed, the liquid crystal injection port is sealed.

If the injected liquid crystal 21 has an alignment defect or the like, the liquid crystal 21 is re-aligned using the above-described method. Finally, the liquid crystal display elements are completed by disposing the polarizing plates 23 and 24.

It should be noted that the present invention is not limited to the above embodiment, and various modifications and applications are possible. For example, the shift angle 2θ of the liquid crystal, that is, the first alignment direction of the liquid crystal 21 and the second
Is arbitrary, and may be 45 ° or less. Further, the arrangement of the polarizing plate and the like are also arbitrary. For example, when the shift angle 2θ of the liquid crystal is 60 ° or more, the transmission axis 23A of the polarizing plate 23 is set at a position 12.5 ° from the first direction 21A, and the transmission axis 24A of the polarizing plate 24 is set to the transmission axis 23A. May be set so as to be orthogonal or parallel to the direction, and the director of the liquid crystal 21 may be driven between the direction of the transmission axis 23A of the polarizing plate 23 and the direction inclined by 45 ° with respect to this direction.

Further, for example, a liquid crystal having a shift angle 2θ of 90 ° or more may be used. In this case, for example, the transmission axis of one polarizing plate may be set to the normal direction of the smectic layer, and the transmission axis of the other polarizing plate may be set to be orthogonal or parallel to the transmission axis of one polarizing plate.

In the above description, the surfaces of the alignment films 18 and 19 were rubbed once in the opposite directions, respectively, but only one alignment film was subjected to such an alignment treatment, and the other alignment film was rubbed. May be subjected to an alignment process in only one direction. The number of rubbing treatments performed on the surfaces of the alignment films 18 and 19 is arbitrary as long as they are parallel to each other.
For example, first rubbing may be performed on the surface of the alignment film 18 in a predetermined direction, second rubbing may be performed in the opposite direction, and then third rubbing may be performed in a predetermined direction.

The liquid crystal 21 may be sealed in the liquid crystal cell 25 in a state where the spiral structure is released, or may be sealed in the liquid crystal cell 25 while maintaining the spiral structure.

The transmission axis 24A of the polarizing plate 24 and the transmission axis 23A of the polarizing plate 23 may be set in parallel. Further, an absorption axis may be used instead of the transmission axis. Also,
The present invention is not limited to a display element using a TFT as an active element, but is also applicable to a display element using an MIM as an active element. Further, according to the present invention, as shown in FIG. 8, a simple matrix type (passive matrix type) display in which a scanning electrode 71 and a signal electrode 72 orthogonal to the scanning electrode 71 are arranged on opposing surfaces of the opposing substrates 11 and 12 is provided. It is also applicable to devices.

[0055]

EXAMPLE A liquid crystal display device was formed using an antiferroelectric liquid crystal composed of the liquid crystal composition represented by the chemical formula 1, and its transmittance characteristics were measured. First, FIG. 9A shows the characteristics of an element in which the surfaces of the alignment films 18 and 19 are rubbed in the opposite directions, respectively, as in the above embodiment, and FIG. FIG. 9C shows the characteristics of an element obtained by rubbing the surface of the alignment films 18 and 19 once in the opposite direction, as shown in FIG. Is shown.

The measurement was performed for each pixel as shown in FIG.
The measurement was performed by applying positive and negative pulse pairs having the same absolute value. The arrangement of the polarizing plates 23 and 24 is different from that in FIG. 3, and the transmission axis of one of the polarizing plates is set in the third direction 21C.
And the transmission axis of the other polarizing plate was perpendicular to the transmission axis of one polarizing plate. In such an arrangement, the applied voltage is zero.
When the display is darkest, the liquid crystal director is
The display becomes the brightest when it is located at a direction of 45 ° with respect to the direction 21C.

As is clear from comparison of FIGS. 9A to 9C, when reciprocal rubbing is applied to both alignment films, a dark black level can be stably displayed and the hysteresis is small. On the other hand, when reciprocal rubbing is performed only on the alignment film 18, the bright level can be displayed stably, but the black level cannot be displayed stably. In the case of the conventional double-sided rubbing, the hysteresis is large, and it is difficult to perform stable display. From this example, it can be understood that the rubbing method of this example is excellent.

[0058]

As described above, according to the display element of the present invention, the direction of the layer structure of the layer structure of the liquid crystal of the smectic phase on the opposing substrate surface is close to the substrate where the normal direction of the layer is opposite. With each other. Therefore, the layer structure of the smectic liquid crystal grown from the vicinity of both substrates of the liquid crystal is appropriately joined at substantially the center in the thickness direction of the liquid crystal. Therefore, a liquid crystal layer having few alignment defects due to bonding can be obtained, and a high-quality image can be displayed.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a structure of a display element according to an embodiment of the present invention.

FIG. 2 is a plan view showing a configuration of a lower substrate of the display element shown in FIG.

FIG. 3 is a diagram showing a relationship between a transmission axis of a polarizing plate and an orientation direction of liquid crystal molecules when the display element shown in FIG. 1 is viewed from above.

FIGS. 4A and 4B are diagrams showing directions of alignment processing when the upper substrate and lower substrate of the display element shown in FIG. 1 are viewed from the alignment film side;
FIG. 4 is a diagram showing a relationship between a layer structure of a liquid crystal molecule in the vicinity and a normal direction of a layer.

FIG. 5 is a diagram schematically illustrating a state in which a layer structure of liquid crystal molecules coincides with an upper substrate side and a lower substrate side.

FIG. 6 is a diagram illustrating a relationship between an applied voltage and transmittance.

FIG. 7 is a diagram for explaining realignment of liquid crystal.

FIG. 8 is a sectional view showing another example of the structure of the display element according to the embodiment of the present invention.

FIG. 9 is a graph showing an applied voltage-transmittance characteristic of the liquid crystal display element according to the example of the present invention.

FIG. 10 is a diagram showing driving waveforms used to obtain the applied voltage-transmittance characteristics shown in FIG.

FIG. 11 is a diagram for explaining a conventional ferroelectric liquid crystal alignment process.

[Explanation of symbols]

11: transparent substrate (lower substrate), 12: transparent substrate (upper substrate), 13: pixel electrode, 14: active element (TF
T), 15: gate line (scan line), 16: data line (gradation signal line), 17: counter electrode, 1
8 ... alignment film, 19 ... alignment film, 20 ... sealing material, 21.
..Liquid crystal, 22 spacer, 23 polarizing plate (lower polarizing plate), 24 polarizing plate (upper polarizing plate), 31 row driver, 32 column driver

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[Procedure amendment]

[Submission date] April 16, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

2. The liquid crystal according to claim 1, wherein the liquid crystal is SmCA ^* phase liquid crystal or SmCA ^* phase liquid crystal.
2. The display element according to claim 1, wherein the display element is made of a CA ^* phase liquid crystal.

5. A first and a second base having electrodes formed on opposing surfaces.
An alignment film is formed on each of the opposite surfaces of the plate, and the surface of the alignment film is formed.
Rubbing each of them in the opposite direction by the same number of times , arranging the first substrate and the second substrate at a predetermined gap such that an intersection angle in the direction of each alignment treatment is 2Φ, A smectic layer between the substrate and the second substrate
Arranging a liquid crystal exhibiting a chiral smectic phase for performing the following steps: heating the liquid crystal to temporarily make it an isotropic phase, and subsequently reorienting it from the vicinity of the first and second substrates .
And smectic reoriented from near each substrate
The normal direction of the layer to the orientation direction of each substrate
Smectic matched in the direction of intersection at intersection angle Φ
A method for manufacturing a display element using a liquid crystal exhibiting a strong potato-electric phase, comprising: forming a black layer ;

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007]

In order to achieve the above object, a display element according to a first aspect of the present invention comprises an electrode on one surface and an electrode which is parallel to and opposite to each other in a first direction.
A rubbed alignment film or a formed first substrate;
An electrode disposed on a surface of the first substrate facing the first substrate , the electrode being parallel to and opposite to the first substrate;
Direction, and the intersection angle with the first direction is in the second direction of 2Φ.
A second substrate formed with an alignment film or the like rubbed the same time each time, and disposed between the first and second substrates, and liquid crystal molecules in the vicinity of the first substrate have liquid crystals of a chiral smectic phase Orienting the normal direction of the layer of the layer structure toward a third direction intersecting the first direction at an intersection angle Φ,
The liquid crystal molecules in the vicinity of the second substrate are aligned with the second normal direction of the layer having the layer structure of the liquid crystal of the chiral smectic phase.
And a liquid crystal of a chiral smectic phase oriented in the third direction intersecting at an intersection angle Φ with the direction.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

According to such a configuration, since the intersection angle of the rubbing direction between the first substrate and the second substrate is set to 2Φ, the smectic layer near the first substrate (the layer that the liquid crystal of the smectic phase has) The direction of the normal to the structural layer) and the direction of the normal to the smectic layer near the second substrate are both the third direction and coincide with each other. Therefore, defects are unlikely to occur in the layer structure of the liquid crystal layer, uniform alignment of liquid crystal molecules can be obtained, and a high-quality image with few alignment defects can be displayed.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

In the rubbing of the first substrate and the second substrate ,
Alignment treatment by, for example, one or more times and the opposite direction of the surface of the alignment film formed on the substrate in a direction parallel to the
This is performed by rubbing once .

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

The liquid crystal is a liquid crystal of SmCA ^* phase or SmCA ^* phase.
It is composed of C ^* -phase liquid crystal and in bulk
Between the cone axis of the helical structure of the liquid crystal and the molecular axis of the liquid crystal
The value of the cone angle 2θ obtained by doubling the tilt angle θ is 45
Liquid crystal having chiral smectic C phase larger than °
The composition. Further, the present invention provides the above-mentioned first aspect.
The respective optical axes of the first and second substrates are substantially
Orthogonally arranged, and the direction of one optical axis is defined by the tilt angle θ.
45 ° from the cone angle 2θ
In the range of the angle smaller than the tilt angle θ by the subtracted angle
A pair of deflecting plates disposed so as to intersect with the third direction.
I have. The pair of deflecting plates are one of the deflecting plates.
Is larger than 22.5 ° with respect to the third direction.
To cross each other within an angle range smaller than the tilt angle θ.
It is arranged.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

[0011] In order to achieve the above object, a method of manufacturing a display device according to a second aspect of the invention, it it oriented in a first and opposing surface of the second substrate having electrodes formed on opposing surfaces
Forming a film, and aligning each surface of the alignment film in the opposite direction.
Rubbing a number of times , arranging the first substrate and the second substrate at a predetermined gap such that an intersection angle between directions of the respective alignment treatments is 2Φ,
Arranging a liquid crystal exhibiting a chiral smectic phase for forming a smectic layer between the substrates, and heating the liquid crystal to temporarily make it an isotropic phase, followed by the first and second liquid crystals. It is re-oriented from 2 near the substrate
And smectic reoriented from near each substrate
The normal direction of the layer to the orientation direction of each substrate
Smectic matched in the direction of intersection at intersection angle Φ
And a step of forming a work layer .

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

According to such a configuration, since the intersection angle of the rubbing direction between the first substrate and the second substrate is set to 2Φ, when the liquid crystal is realigned, the smectic layer near the first substrate is used. The direction of the normal line of the (layer having a layered structure of the liquid crystal in the smectic phase) and the direction of the normal line of the smectic layer near the second substrate are both the third direction and coincide with each other. Therefore , defects are less likely to occur in the layer structure at the center of the liquid crystal layer, uniform alignment of liquid crystal molecules can be obtained, and a high-quality image with few alignment defects can be displayed.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction contents]

[0013] each of the first substrate and the second substrate La
The step of performing the orientation treatment by bing is performed, for example, by forming the substrate.
The surface of the formed alignment film is moved in parallel and in the opposite direction by 1
It is performed by the process of rubbing the same number of times or multiple times
It is.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tetsushi Yoshida 5 Casio Computer Co., Ltd. Hachioji Research Laboratory, 2951 Ishikawacho, Hachioji-shi, Tokyo

Claims (5)

[Claims] An electrode is formed on one surface, and a first substrate that has been subjected to an orientation treatment in a first direction is disposed on a surface facing the first substrate. An electrode is formed, a second substrate having an intersection angle with the first direction oriented in a second direction having a diameter of 2Φ is disposed between the first substrate and the second substrate, and the first substrate is disposed between the first substrate and the second substrate; The liquid crystal molecules in the vicinity of the substrate are oriented in a third direction intersecting the normal direction of the layer of the layer structure of the liquid crystal of the chiral smectic phase at the intersection angle Φ with the first direction, and
Liquid crystal molecules in the vicinity of the substrate are oriented in the third direction in which the normal direction of the layer structure of the layer structure of the liquid crystal of the chiral smectic phase intersects with the second direction at the intersection angle Φ. A display element using a liquid crystal having a ferroelectric phase composed of: 2. The display element according to claim 1, wherein an alignment film rubbed a plurality of times in opposite directions is formed on the surfaces of the first and second substrates, respectively. . 3. The liquid crystal according to claim 1, wherein the liquid crystal is an S _m CA ^* phase liquid crystal or S _m C ^*.
The display element according to claim 1, wherein the display element is made of phase liquid crystal. 4. A step of subjecting each of the first and second substrates, each having an electrode formed on the opposing surface, to an orientation process, and setting the first substrate and the second substrate to have an intersection angle of 2Φ in the direction of the orientation process. A step of arranging the smectic layer between the first and second substrates in a direction intersecting at a crossing angle Φ with respect to the direction of the alignment process between the first and second substrates. Arranging a liquid crystal of a chiral smectic phase oriented in a direction intersecting at an intersection angle Φ with respect to the orientation processing direction; and heating the liquid crystal to temporarily make it an isotropic phase, and then, the first and second A method of producing a display element using a liquid crystal exhibiting a ferroelectric phase, comprising: a step of re-orienting from the vicinity of a substrate. 5. The step of subjecting each of the first and second substrates to an alignment treatment includes the steps of: forming an alignment film on the opposing surfaces of the first and second substrates, respectively; 5. The method according to claim 4, further comprising: rubbing a plurality of times in opposite directions.