JPH11133391A - Liquid crystal device and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the defect of color display and to improve color reproducibility by improving the structure and a process for production of a liquid crystal cell in a color liquid crystal device of a reflection type having a liquid crystal layer dispersed and mixed with liquid crystals and high polymers of a high polymer dispersion type, etc. SOLUTION: A reflection layer 51 is formed on the inside surface of a rear surface side substrate 50 and color filters 52 consisting of colored layers R, G, B and a transparent protective film T are composed on the surfaces thereof. Transparent electrodes 53 consisting of ITO, etc., are formed in correspondence to pixel regions on the surface of the protective film T of the color filters 52. The surface of the transparent electrodes 53 is coated with an alignment layer 54 which is subjected to a rubbing treatment in a prescribed direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a liquid crystal device.

[0002]

2. Description of the Related Art Hitherto, various liquid crystal devices having a structure in which a liquid crystal layer is sandwiched between two substrates having electrodes on the inner surface have been manufactured. Among these, there is a reflection type liquid crystal device in which a reflection layer is formed on the back surface side of a liquid crystal layer. In this reflection type liquid crystal device, a color liquid crystal device having a color filter may be formed.

FIG. 10 schematically shows a structural example of a conventional reflection type color liquid crystal device. Colored layers R, G, and B formed on the inner surface of the front-side substrate 10 made of glass or the like and having any color tone arranged in a predetermined arrangement order and arranged in a predetermined arrangement order in each pixel region; These colored layers R,
A color filter 11 composed of a transparent protective film T covering G and B is formed. A transparent electrode 12 made of a transparent conductive material such as ITO (indium tin oxide) is formed on the surface of the color filter 11 so as to correspond to any one of the coloring layers R, G, and B. An alignment film 13 made of polyimide, polyvinyl alcohol, or the like is formed on the surface of the transparent electrode 12 through steps such as application and baking, and the surface is subjected to a known rubbing treatment.

On the other hand, on the inner surface of the backside substrate 20, a reflective electrode 21 serving as a reflective layer and a pixel electrode is formed of a metal such as Al or Cr. A transistor element such as a MOSFET or a TFT (thin film transistor) connected between a wiring layer (not shown) and the reflective electrode 21 and a MIM (metal-insulator-metal) element are formed on the inner surface of the back-side substrate 20. A known switching element 22 including a diode element such as a TFD (thin film diode) is formed.

[0005] The front substrate 10 and the rear substrate 20 are adhered to each other via a sealing material (not shown), and liquid crystal is injected between the front substrate 10 and the rear substrate 20. In this conventional example, a polymer-dispersed liquid crystal layer 30 is provided between the front substrate 10 and the rear substrate 20. The polymer-dispersed liquid crystal layer 30 is one form of a liquid crystal layer in which liquid crystal having refractive index anisotropy and dielectric anisotropy and a polymer are dispersed and mixed. , Liquid crystal molecules 31 and polymer particles 32 are dispersed and mixed. FIG. 10 schematically illustrates the liquid crystal layer 30. For example, polymer particles may be discretely dispersed in the liquid crystal as shown in the drawing, or the polymer particles may be close to each other. Sometimes they are arranged in a bunch of grapes.

In the manufacturing process of this liquid crystal device, the gap between the front substrate 10 and the back substrate 20 is usually about several μm, and a predetermined liquid crystal and a polymer precursor having photopolymerizability are filled in the gap. A solution compatible with the polymer (monomer, prepolymer, etc.) is injected, and then the liquid crystal cell is irradiated with ultraviolet light from the side of the front substrate 10 to photopolymerize the polymer precursor in the solution to polymer. The particles are deposited to form the liquid crystal layer 3 described above.
0 is formed.

In the state where no electric field is applied, the liquid crystal molecules 31 and the polymer particles 32 in the liquid crystal layer 30 are subjected to the rubbing direction (horizontal direction) applied to the alignment films 13 and 23 as shown in FIG.
Along with each other. When a voltage exceeding a predetermined threshold is applied between the transparent electrode 12 and the reflective electrode 21, the liquid crystal molecules 31 having dielectric anisotropy are oriented in the direction of an electric field (vertical direction) and change their posture. As a result, since the refractive index of the liquid crystal molecules 31 having the refractive index anisotropy viewed from the outside changes, the liquid crystal molecules 31 are oriented in almost the same direction as the polymer particles 32, and the electric field is not applied. Liquid crystal molecules 31
The difference in the light refractive index between the polymer and the polymer particles 32 also changes.

In the liquid crystal layer 30, for example, if the difference between the refractive indices of the liquid crystal molecules 31 and the polymer particles 32 is substantially zero in the state where no electric field is applied, the liquid crystal layer 30 becomes substantially transparent, and Is transmitted through the liquid crystal layer 30, reflected by the reflective electrode 21, and emitted again as it is. Conversely, when the electric field is applied, a change in the refractive index of the liquid crystal molecules 31 causes a difference in the refractive index with the polymer particles 32, so that the liquid crystal layer 30 becomes cloudy,
Light incident on the cell is scattered by the liquid crystal layer 30. Of course, it is also possible to make the liquid crystal layer in a scattering state when no electric field is applied and to make the liquid crystal layer in a transmission state when an electric field is applied.

[0009]

However, in the above-described conventional process of manufacturing a polymer-dispersed liquid crystal device, since the color filter 11 is formed on the inner surface of the front substrate 10, the liquid crystal cell is exposed to ultraviolet light. , The ultraviolet light is transmitted through each of the colored layers R, G, and B of the color filter 11 and is irradiated to the solution. In this case, since the transmittance of the colored layers R, G, and B to ultraviolet rays generally differs, the amount of light irradiation increases and decreases depending on the color tone of the colored layers R, G, and B in each pixel region. The optical characteristics with respect to the voltage greatly differ depending on the color tone of the colored layer.

For example, FIG. 4 shows that each of the colored layers R (30), G (3) having a minimum transmittance of 30% in the visible light region.
7 shows the results of measuring the transmittance in the ultraviolet region at 0) and B (30). Usually, in the process of forming the above-mentioned liquid crystal layer 30, ultraviolet rays in a wavelength range of about 350 to 360 nm are used. The rate change is steep. As a result, as shown in FIG. 5, when the relationship between the drive voltage of the pixel and the reflectance of the liquid crystal cell is measured for each of the coloring layers R, G, and B formed in each pixel region, the driving is performed according to the color tone of the coloring layer. It can be seen that the characteristics and electro-optical characteristics change significantly. Due to this change, the optical threshold voltage Vth and the optical saturation voltage Vsat of the liquid crystal cell are largely different from each other at the same UV irradiation intensity as shown in FIGS. 6 and 7, and the color tone is changed when the UV irradiation intensity is changed. This leads to a complicated situation in which the characteristic differences also change.

Such variations in the electro-optical characteristics due to the color tone and the manufacturing process conditions (light irradiation amount) cause a mismatch in the luminance between the color tones of the color liquid crystal device, thereby impairing the color display and impairing the color reproducibility. There is a problem that causes serious defects. In particular, a color shift amount in a halftone occurs and a driving range having color reproducibility is limited, thereby deteriorating display quality.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a reflection type color liquid crystal device having a liquid crystal layer in which a liquid crystal and a polymer are dispersed and mixed, such as a polymer dispersion type. It is an object of the present invention to provide a technique capable of improving display quality, such as defective color display, color reproducibility, and the like, by improving the structure and manufacturing method of a liquid crystal cell.

[0013]

Means taken by the present invention to solve the above problem is that a liquid crystal layer is sandwiched between a pair of substrates, and a reflection layer is disposed on one of the substrates. A color filter is formed on the reflective layer, and an electrode is formed on the color filter.

According to this means, since the color filter is disposed on the back surface side (one substrate side) of the liquid crystal layer, it is not necessary to provide the color filter on the inner surface of the substrate on the front side where light enters. Therefore, it is possible to suppress variations in the light scattering state between pixels exhibiting different colors due to the wavelength dependence of the scattering. Further, since the light-transmitting electrode is disposed closer to the liquid crystal layer than the color filter, a voltage drop due to the color filter can be eliminated. Furthermore, when a polymer-dispersed liquid crystal is interposed, even if light is irradiated from the surface side when performing photopolymerization for producing a polymer, the difference is caused by a difference in light transmittance between the colored layers of the color filter. Since there is no difference in the amount of light irradiation, the dependence of electro-optical characteristics due to the color tone of the colored layer of the color filter in the liquid crystal layer is reduced. The electric field application range can be increased.

Here, it is preferable that a reflective layer, a color filter, and an electrode are sequentially laminated on the inner surface of the substrate. Such a configuration is the most realistic, and the manufacturing cost can be reduced. For example, it is possible to provide a reflective layer on the outer surface of the back-side substrate and stack a color filter and electrodes on the inner surface of the back-side substrate.
In addition to being difficult to handle at the time of manufacture, the backside substrate is interposed between the liquid crystal layer and the reflective layer, and there is a possibility that double display of a display may occur or the brightness of the display may decrease.

In this structure, the liquid crystal layer is preferably formed by dispersing a polymer in liquid crystal, but is not particularly limited, and a normal TN type liquid crystal can be used. It is.

Further, it is preferable that a protective film for covering the surface of the color filter is provided, and the surface of the protective film is roughened. According to this means, since the surface of the protective film covering the color filter is roughened, reflection of the background and external light in the light transmitting state of the liquid crystal layer can be prevented, and visibility can be improved. .

Further, it is preferable that the thickness of the electrode is formed so as to be capable of interfering with light having a wavelength substantially corresponding to the color tone of the coloring layer of the color filter. According to this means, the color tone of each pixel can be displayed more vividly because the translucent electrode is formed to a thickness capable of interfering with light having a wavelength substantially corresponding to the color tone of the color layer of the color filter. Therefore, display quality and contrast can be improved.

And a switching element on the other substrate,
A pixel electrode connected to the switching element is formed. Further, the invention is characterized in that the reflection layer is formed corresponding to the electrode.

According to this means, since the counter electrode and the switching element are formed on the inner surface of the front substrate, the switching element formation substrate having a high defect rate and the reflection layer formation substrate are separated from each other. And can be manufactured in separate manufacturing steps, so that the yield of the entire liquid crystal device can be improved,
Manufacturing costs can be reduced.

Next, in a method of manufacturing a liquid crystal device in which a liquid crystal is sandwiched between a pair of substrates, and a reflection layer and a color filter are formed on one substrate, a surface of the one substrate on a liquid crystal layer side is provided. Forming a reflective layer, a color filter, and an electrode, forming a counter electrode on the other substrate, laminating the pair of substrates to form a liquid crystal cell, and forming a liquid crystal inside the liquid crystal cell. A method for manufacturing a liquid crystal device, comprising at least a step of injecting a layer.

Here, it is preferable that the reflection layer is formed in substantially the same plane pattern as the translucent electrode. It is preferable that a liquid crystal cell is irradiated with light to form a liquid crystal layer in which a polymer is dispersed in the liquid crystal.

[0023]

Next, an embodiment according to the present invention will be described with reference to the accompanying drawings. In FIGS. 1 to 3 referred to below, the structure of the liquid crystal device of each embodiment is simplified and schematically shown, and the detailed structure of the wiring layer and the switching element is omitted.

(First Embodiment) FIG. 1 shows a schematic configuration of a first embodiment of a liquid crystal device according to the present invention. FIG.
A liquid crystal layer 30 is sealed in a liquid crystal cell including a front substrate 40 and a rear substrate 50 similar to those of the liquid crystal device shown in FIG. Are arranged in a distributed manner. The liquid crystal layer 30 formed in the present embodiment is a polymer-dispersed liquid crystal layer in which a polymer is dispersed in liquid crystal.

The polymer-dispersed liquid crystal layer is formed by polymerizing a polymer precursor from a solution in which a liquid crystal and a polymer precursor are dissolved, and by phase-separating the liquid crystal and the polymer. preferable. On the other hand, as the liquid crystal, a nematic liquid crystal having dielectric anisotropy and refractive index anisotropy and other various liquid crystals can be used. As the liquid crystal, for example, a nematic liquid crystal to which a chiral component is added may have a twist angle in the liquid crystal layer. When the twist angle is in the range of 0 to 180 degrees, electro-optical characteristics are generated depending on the incident direction of light. By providing a twist angle of 270 degrees or more, anisotropy of electro-optical characteristics due to light can be reduced.

As the polymer precursor, various polymer precursors (monomer, prepolymer, etc.) which can be controlled in polymerization can be used. In particular, if the polymer precursor has a benzene skeleton or a biphenyl skeleton, Regardless of thermoplastic polymer, thermosetting polymer, photo-curing polymer,
Can be widely used. For example, methacrylates or acrylates of phenylphenol or derivatives of these compounds can be used, and methacrylates or acrylates of hydroxyterphenyl or derivatives of these compounds can be used. . Further, a mixture of the ester and a methacrylate derivative or acrylate derivative of biphenol may be used as the polymer precursor.

In the polymer-dispersed liquid crystal layer, it is preferable that liquid crystal molecules and polymer particles are aligned in the same direction in an initial state (in a state where no electric field is applied). In this case, it is desirable that the liquid crystal molecules and the polymer precursor in the solution are aligned in the same direction, and phase separation is performed while maintaining the alignment state during polymerization of the polymer precursor. By doing so, the refractive index of the liquid crystal layer can be reliably controlled, so that the optical characteristics of the liquid crystal layer can be improved.

Further, as the polymer, even if the polymer is formed by cooling and curing using a thermoplastic polymer precursor, heating or light irradiation may be performed using a thermosetting or photocurable polymer precursor. The polymerization may be carried out. However, in order to facilitate control in the manufacturing process and to prevent the influence on other materials, it is most preferable to use a photocurable polymer precursor and to phase separate the polymer particles by photopolymerization. It is effective. Particularly, polymerization by ultraviolet irradiation is the most practical method.

The ratio of the liquid crystal contained in the liquid crystal layer is 5% of the whole.
0 to 97 wt% is optimal. If the liquid crystal content is less than this, it is difficult to respond to an electric field, and if it is more than this, the contrast is reduced.

In this embodiment, a transparent electrode 41 made of ITO or the like and a switching element 42 are formed on the inner surface of the above-mentioned front substrate 40. Switching element 4
Reference numeral 2 is provided between a wiring layer (not shown) and the transparent electrode 41, and is used as a switching element for supplying a predetermined potential to the transparent electrode 41. An alignment film 43 is formed on the surfaces of the transparent electrode 41 and the switching element 42, and is subjected to a rubbing process.

On the other hand, Al, Cr, Ag, etc. formed corresponding to the pixel region are deposited on the inner surface of the backside substrate 50 by evaporation.
The reflective layer 51 deposited by sputtering or the like is formed. On the surface of each reflective layer 51, a colored layer R (red),
One of G (green) and B (blue) is formed, and all the colored layers R, G, and B are covered with a transparent protective film T to form a color filter 52. The method for producing the colored layer of the color filter 52 is generally such that the application of a colored material and the patterning by photolithography are repeated for each color. By overlapping two or three of the colored layers R, G, and B with each other or forming a black layer containing both R, G, and B pigments, a black matrix is formed in an area between the pixel areas. A layer may be formed.

On the surface of the protective film T of the color filter 52, a transparent electrode 5 made of ITO or the like corresponding to the pixel region is provided.
3 is formed. The surface of the transparent electrode 53 is covered with an alignment film 54 and rubbed in a predetermined direction. As a formation position of the color filter, a structure in which a color filter is formed on a reflection electrode which also serves as a reflection layer formed on a substrate is also conceivable. Since the capacitance is not negligible with respect to the liquid crystal capacitance, there is a problem that a sufficient effective voltage is not applied to the liquid crystal layer, which causes a decrease in contrast, a rise in the threshold voltage of the element, and a loss of sharpness of the rise. . In the present embodiment, by adopting the above structure, the driving performance of the liquid crystal is prevented from lowering.

On the other hand, when the above structure is adopted, when the reflective layer 51 is formed of a conductor such as a metal as in the present embodiment, a capacitance is formed by the reflective layer 51 and the transparent electrode 53. Therefore, if the reflective layer 51 is formed entirely on the inner surface of the backside substrate 50 or is formed in a stripe shape, crosstalk between pixels may occur. However, in the present embodiment, the reflection layer 51
Are formed in substantially the same plane pattern as the transparent electrode 53, so that the capacitance between the reflective layer 51 and the transparent electrode 53 does not cause crosstalk. The switching element 42 is connected to the front substrate 40.
Is formed on the inner surface of the switching element and the influence of the capacitance component between the switching element and the reflection layer 51 is also prevented.

When scanning lines are formed on the surface of the front substrate 40, the reflection layer 51 may be provided in a stripe shape for each scanning line. In this way, even if the reflective layer 51 is continuous between the pixels connected to the same scanning line, the same potential is supplied to these pixels, so that the capacitance between the reflective layer and the reflective layer 51 is increased. This is because no crosstalk due to is caused.

In the present embodiment, a liquid crystal cell is formed by bonding the front substrate 40 and the rear substrate 50 at intervals of about several μm via a sealing material (not shown), and the above-described solution is placed in the liquid crystal cell. When injected, the liquid crystal molecules and the polymer precursor in the solution are aligned in the rubbing direction (horizontal direction) of the alignment film. By irradiating ultraviolet rays in this state, the polymer particles are phase-separated, and the liquid crystal layer 30 can be formed.
Ultraviolet light is applied to the solution from the front substrate 40 side.

In the conventional liquid crystal device, since the solution is irradiated with ultraviolet rays through the color filter, as shown in FIGS. 6 and 7, the optical threshold voltage Vth and the optical saturation voltage Vsat change the color of the color filter. There was a large variation in both the color tone of the layer and the irradiation amount of ultraviolet rays. However, even in such a case, as shown in FIGS. 8 and 9, the product of the ultraviolet transmittance and the ultraviolet irradiation intensity of each colored layer, the optical threshold voltage Vth, and the optical saturation voltage Vsat
It has been found that the relationship is on a predetermined curve (dotted line in the figure) irrespective of the color tone of the colored layer of the color filter. That is, the conventional variation in the electro-optical characteristics is substantially affected only by the light transmittance of the ultraviolet light by the color filter.

As shown by the data in FIGS. 8 and 9, in this embodiment, the photopolymerization of the polymer is uniformly performed by irradiating ultraviolet rays from the front substrate 40 without passing through a color filter. Therefore, a uniform driving state of the liquid crystal layer can be realized without being affected by the color tone of the coloring layer of the color filter, and the accuracy of display colors can be improved.
Variations in display colors can be reduced. In particular, FIG.
The amount of color shift in halftone due to the electro-optical characteristics described in (1) is suppressed, and the range in which reproducibility of display colors can be secured can be widened.

In the present embodiment, an appropriate pixel is selected by the transparent electrode 41 and the transparent electrode 53 to be in a cloudy state, and an unselected pixel is kept in a transparent state. When all three pixels having the adjacent coloring layers R, G, and B are not selected, the pixel is visually recognized as black, and the adjacent coloring layers R, G, and B are viewed.
When one or two of the pixels having G and B are selected, the color tone generated by the white color of the selected pixel and the color tone of the coloring layer of the remaining pixels is visually recognized. When pixels of all tones are selected, white is visually recognized. Of course, by adjusting the driving voltage applied to each pixel, an intermediate state can be formed in each pixel. In this case, various tones in which the intermediate state of each pixel is combined with pixels of other colors are reproduced. It is possible.

Not only in this embodiment, but in the manufacturing process of a reflective type color liquid crystal device having a switching element such as a thin film transistor or a non-linear element, the most important viewpoints in yield are the switching element and the reflection layer. Since the characteristics of the switching element are greatly affected by its structure, film quality, and the like, the yield is low. In particular, the characteristics of the MIM element are extremely sensitive to the quality of the insulating film and the junction area. In addition, although the reflective layer is also defective due to oxidation of the metal surface, the yield is relatively poor because Al and Ag having high reflective performance are particularly easily oxidized. In the conventional structure, as shown in FIG. 10, the reflective electrode and the switching element are formed almost simultaneously on the inner surface of the back side substrate 20, so that the back surface is determined by the product of the yield of the switching element and the yield of the reflective electrode. The yield of the side substrate 20 is considerably low, which has been a factor of increasing the manufacturing cost.

On the other hand, in this embodiment, the switching element is formed on the inner surface of the front substrate 40, the reflection layer is formed on the inner surface of the rear substrate 50, and the switching element and the reflection layer are formed in separate processes. In this case, the failure of the switching element is caused by the front side substrate 40.
Since the defect of the reflective layer can be eliminated by the inspection at a relatively early stage in the manufacturing process of the backside substrate 50, the yield of the entire liquid crystal device can be reduced. It can be greatly improved compared to the conventional case.

Further, in the conventional example shown in FIG. 10, since a color filter is formed on the inner surface of the front substrate 10, the wavelength of light incident on the liquid crystal layer 30 from the front side differs depending on the coloring layer. In the light scattering state of the composite layer 30, the wavelength dependence of the scattering (the light scattering intensity is 4 times the light frequency)
Since it is proportional to the power, it is greatly affected by the wavelength of light. ), The light scattering state changes depending on the color tone of the light transmitted through the color filter. For this reason, since the scattering intensities between the pixels exhibiting different color tones are different from each other, there is a problem that the reproducibility of the color tone and the brightness of the color display is poor. But,
In this embodiment, since no color filter is provided on the front-side substrate 40, the incident light is almost the same as the external light in any pixel, and the dispersion of the scattering intensity due to the wavelength dependence of the scattering is greatly reduced. There is also the advantage that it hardly occurs.

Although the liquid crystal in which the polymer is dispersed has been described in the present embodiment, a normal TN type liquid crystal or STN type liquid crystal can be applied. Furthermore, the present invention is also applicable to liquid crystals that are vertically aligned. When these liquid crystals are used, a polarizing means such as a polarizing plate is arranged on at least the substrate on which light is incident to form a liquid crystal device. When these liquid crystals are used, it is also possible to arrange at least one film such as a retardation plate to compensate for coloring and viewing angle. It goes without saying that these liquid crystals can also be used in the following embodiments.

(Second Embodiment) Next, a liquid crystal device according to a second embodiment of the present invention will be described with reference to FIG. In this embodiment, a liquid crystal layer 30, a front substrate 40, a transparent electrode 41, a switching element 42, an alignment film 43, a rear substrate 50, a reflective layer 51, a color filter 52, and a transparent electrode are substantially the same as those in the first embodiment. 53 and an alignment film 54, except that the surface of the protective film T 'of the color filter 52 is formed in a rough surface. As the protective film T ′, for example, there is a film formed by applying a thermosetting acrylic resin by a spin coating method and then baking it at 180 ° C. for about 30 minutes. After forming the protective film T ′, the surface is roughened by a method such as soft etching or dry etching to form a fine uneven structure, and the protective film T ′ and the transparent electrode 53 are formed.
It is configured such that light is scattered optically at the interface with the substrate.

In this embodiment, since the surface of the protective film T 'is roughened, the upper transparent electrode 5 having a different refractive index is used.
The light reflected by the reflective layer 51 passes through the colored layer, is scattered, passes through the liquid crystal layer 30 and the front substrate 40, and is scattered. enter. For this reason, even when the liquid crystal layer 30 is in the light transmitting state, the reflection of the background and external light is reduced, and the visibility can be improved.

(Third Embodiment) FIG. 3 shows a liquid crystal device according to a third embodiment of the present invention. This embodiment also has substantially the same structure as the first embodiment, except that the thicknesses of the transparent electrodes 53r, 53g, and 53b disposed above the colored layers R, G, and B are different from each other. Are different.

In this embodiment, the transparent electrode 53r is formed to have an optical thickness corresponding to a typical wavelength of red light transmitted through the colored layer R. That is, a typical wavelength of red light is λr (for example, about 650 to 750 nm),
Assuming that the refractive index of the transparent electrode 53r is εITO 2,
When the thickness dr of the transparent electrode 53r is set to approximately λr / εITO or a thickness that is a natural number multiple thereof, the color tone of the interference color by the transparent electrode 53r and the light transmitted from the color filter 52 are almost the same. Vividness and contrast of colors can be improved.

Similarly to the above, regarding the transparent electrodes 53g and 53b, if a typical wavelength of green light is λ _g and a typical wavelength of blue light is λ _b , d _g = λ _g / ε _ITO d _The film may be formed by adjusting the thickness so that _b = λ _b / ε _ITO . Specifically, a method of providing a film forming step of three transparent electrodes having different thicknesses, or a method of etching only two thinner transparent electrodes can be considered.

[0048]

As described above, according to the present invention, since the color filter is disposed on the back side of the liquid crystal layer, light is emitted from the front side when performing photopolymerization for generating a polymer. Irradiation does not cause a difference in light irradiation amount due to a difference in light transmittance between the colored layers of the color filter, so that the dependence of the electro-optical characteristics on the color tone of the colored layer of the color filter in the liquid crystal layer is reduced. In particular, it is possible to suppress the amount of color shift in a halftone and to increase the electric field application range with color reproducibility. In addition, since it is not necessary to provide a color filter on the inner surface of the front substrate on which light is incident, it is possible to suppress variations in the light scattering state between pixels exhibiting different colors due to the wavelength dependence of scattering. Further, since the light-transmitting electrode is disposed closer to the liquid crystal layer than the color filter, a voltage drop due to the color filter can be eliminated.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view illustrating a schematic structure of a liquid crystal device according to a first embodiment of the invention.

FIG. 2 is a schematic sectional view illustrating a schematic structure of a liquid crystal device according to a second embodiment of the invention.

FIG. 3 is a schematic sectional view illustrating a schematic structure of a liquid crystal device according to a third embodiment of the invention.

FIG. 4 is a graph showing a light transmittance of each color tone of a color filter of a conventional liquid crystal device in an ultraviolet region.

FIG. 5 is a graph showing electro-optical characteristics for each color tone of a color filter of a conventional liquid crystal device.

FIG. 6 is a graph showing a relationship between an optical threshold voltage and an ultraviolet irradiation intensity for each color tone of a color filter of a conventional liquid crystal device.

FIG. 7 is a graph showing a relationship between an optical saturation voltage and an ultraviolet irradiation intensity for each color tone of a color filter of a conventional liquid crystal device.

FIG. 8 is a graph showing a relationship between an optical threshold voltage in each pixel of a conventional liquid crystal device and a product of an ultraviolet transmittance and an ultraviolet irradiation intensity of a colored layer of a color filter in the pixel.

FIG. 9 is a graph showing a relationship between an optical saturation voltage at each pixel of a conventional liquid crystal device and a product of an ultraviolet transmittance and an ultraviolet irradiation intensity of a colored layer of a color filter in the pixel.

FIG. 10 is a schematic sectional view showing the structure of a conventional liquid crystal device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 30 liquid crystal layer 31 liquid crystal molecules 32 polymer particles 40 front substrate 41 transparent electrode 42 switching element 43 alignment film 50 rear substrate 51 reflection layer 52 color filter 53 transparent electrode 54 alignment film R, G, B coloring layer T, T ′ Protective film

Claims (10)

[Claims] 1. A liquid crystal layer is sandwiched between a pair of substrates, a reflection layer is disposed on one substrate, a color filter is formed on the reflection layer, and an electrode is formed on the color filter. A liquid crystal device characterized by being formed. 2. The liquid crystal device according to claim 1, wherein the reflection layer is formed on the liquid crystal layer side of the one substrate. 3. The liquid crystal device according to claim 1, wherein the liquid crystal layer is formed by dispersing a polymer in liquid crystal. 4. The liquid crystal device according to claim 1, wherein a protective film is formed on a surface of the color filter, and the surface of the protective film is roughened. 5. The method according to claim 1, wherein the thickness of the electrode is formed so as to be capable of interfering with light having a wavelength substantially corresponding to the color tone of the color layer of the color filter. Characteristic liquid crystal device. 6. The liquid crystal device according to claim 1, wherein a switching element and a pixel electrode connected to the switching element are formed on the other substrate. 7. The liquid crystal device according to claim 1, wherein the reflection layer is formed corresponding to the electrode. 8. A method for manufacturing a liquid crystal device comprising a pair of substrates sandwiching liquid crystal, and a reflective layer and a color filter formed on one substrate, wherein the one substrate has a surface facing the liquid crystal layer. A step of forming a reflective layer, a color filter, and an electrode; a step of forming a counter electrode on the other substrate; a step of bonding the pair of substrates to form a liquid crystal cell; and a liquid crystal layer inside the liquid crystal cell. And a step of injecting a liquid crystal. 9. The method according to claim 8, wherein the liquid crystal cell is irradiated with light to form the liquid crystal layer in which a polymer is dispersed in the liquid crystal. 10. The method according to claim 8, wherein the reflective layer is formed in a substantially same plane pattern as the electrodes.