JP2000105370A - Reflection plate as well as reflection type display element and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to improve the utilization efficiency of incident light and to brightly reflect the light to a direction within a prescribed angle range. SOLUTION: This display element has a reflection plate 1, a counter substrate 2 facing the reflection plate 1 and a liquid crystal layer 3 held between the reflection plate 1 and the counter substrate 2. The reflection plate 1 is disposed on a glass substrate 11 and the surface layer portion thereof has a photosensitive resin layer 9 formed as plural rugged surfaces inclining in a prescribed direction and a reflection film 10 disposed on the photosensitive resin layer 9. As a result, the reflection of the light in a specular reflection direction where mirroring-in occurs is averted and the reflection of the light in a direction where visibility is good is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflection plate used for a reflection type display device provided with a light receiving type light modulation medium such as a liquid crystal.
And a reflective display element and a method for manufacturing the same.

[0002]

2. Description of the Related Art Liquid crystal display devices have been widely used in portable information terminal displays and the like because of their thin and lightweight characteristics. Since liquid crystal is a light-receiving element that does not emit light by itself, in general, a reflective liquid crystal display element that arranges a reflective plate on the back of the liquid crystal panel and displays by utilizing the reflection of external light, and a backlight on the back of the liquid crystal panel And
It can be classified into a transmissive liquid crystal display element which displays by projecting the light of the backlight.

As is well known, a liquid crystal can be driven at a low voltage of several volts, and in the case of the above-mentioned reflective liquid crystal display element, display is performed by using external light without using a backlight. Power consumption. The reflective liquid crystal display element
As described above, aluminum (Al) is provided on the back side of the liquid crystal layer.
Or, a structure in which a scattering reflection plate made of silver (Ag) or the like is arranged, but there is also a structure in which a scattering reflection plate with a polarizing plate is provided outside the glass, such as a reflection-type liquid crystal display element for displaying black and white such as a wristwatch. is there.

Here, Japanese Patent Application Laid-Open No. Hei 4-243226 discloses a reflective liquid crystal display panel in which external light is scattered / reflected by a scattering / reflecting plate without using a backlight for display. .

[0005] The scattering reflector described in the above publication is manufactured by the method described below in order to form the reflecting surface with a uniform shape with good reproducibility. That is, FIG.
As shown in (a), a resist film 102 is applied on a glass substrate 101. Next, as shown in FIG.
The resist film 102 is covered with a photomask 103 patterned into a predetermined shape and exposed. Subsequently, the exposed resist film 102 is developed with a developer, and FIG.
Are formed as shown in FIG. In the cross-sectional shape of the convex portion 104, the corner is substantially a right angle, so it is necessary to round the corner of the convex portion 104. Therefore, the shape as shown in FIG. 12D is obtained by performing the heat treatment. Further, A is formed on the glass substrate 101 on which the convex portions 104 are formed.
g is deposited to form a reflective film 106.

[0006]

However, the projections of the reflection plate in the reflection type liquid crystal display panel described in the above publication are formed by ordinary patterning using a photomask, and the cross-sectional shape is It is symmetric. As a result, the light scattered / reflected by the scattering / reflecting plate is also reflected in a viewing direction of an observer, for example, in a direction other than the normal direction of the substrate, according to the shape of the projection. Therefore, external light cannot be used effectively.

More specifically, a regular reflection surface parallel to the substrate surface always exists between the inclined convex portions, and when incident light is regularly reflected by the regular reflection surface. It is not reflected in the normal direction of the substrate. Moreover, on the counter substrate surface made of glass or the like, a part of the incident light is specularly reflected to cause glare of illumination, and the direction in which the glare occurs coincides with the direction in which the reflected light has the highest light intensity. Therefore, visibility of display in the brightest direction is deteriorated. Therefore, the observer views the display screen from a slightly dark direction, and has a problem that the display screen cannot be observed from the brightest direction.

Further, in the reflection type liquid crystal display device described in the above publication, an exposure step is performed using a photomask patterned into a predetermined shape in order to form a convex portion in the reflection plate. Manufacturing processes are increasing. Furthermore,
In the above-mentioned exposure step, alignment between a photomask and a glass substrate on which a resist film is formed is required. However, if this alignment is not performed accurately, a reduction in yield is caused, leading to an increase in cost. There is a problem that.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a reflection plate having excellent reflection characteristics, a reflection type display device having the same, and a method of manufacturing the same.

[0010]

In order to solve the above-mentioned problems, the invention according to claim 1 comprises a photosensitive resin layer provided on a substrate and a reflective resin layer provided on the photosensitive resin layer. In the reflection plate having a film, the surface of the photosensitive resin layer has an uneven surface, and the concave or convex portion constituting the uneven surface has a cross-sectional shape inclined in a certain direction, The reflected light is condensed in a specific direction.

According to the above structure, the surface of the photosensitive resin layer has an uneven surface, and the concave or convex portion constituting the uneven surface has a cross-sectional shape inclined in a certain direction. There is no specular reflection plane parallel to the plane. As a result, it is possible to reflect most of the light incident from a predetermined direction at a certain incident angle, not in the specular reflection direction, but in the viewing direction of the observer, for example, in the normal direction of the substrate. Therefore, the utilization efficiency of the incident light can be improved, and the incident light can be reflected brightly in a direction within a predetermined angle range.

According to another aspect of the present invention, there is provided a reflector having a photosensitive resin layer provided on a substrate and a reflective film provided on the photosensitive resin layer. Wherein the photosensitive resin layer is formed by exposing and developing a photosensitive resin material formed on the substrate from an oblique direction with respect to the substrate surface through a mask. A first photosensitive resin layer having a plurality of concave or convex portions having an asymmetric cross-sectional shape inclined in a certain direction by the exposure from the oblique direction;
It is characterized by comprising a second photosensitive resin layer provided on the photosensitive resin layer along the shape of the first photosensitive resin layer.

[0013] In the above configuration, the photosensitive resin layer includes a first photosensitive resin layer having a plurality of concave portions or convex portions so that a regular reflection surface parallel to the substrate surface is not formed on the reflector.
It has a two-layer structure with the second photosensitive resin layer provided on the first photosensitive resin layer. Thereby, the portions of the first photosensitive resin layer where the concave portions or the convex portions are separated can also be formed as a gently inclined uneven surface.

According to a third aspect of the present invention, in the reflection plate according to the second aspect, the mask is provided between the substrate and the photosensitive resin layer, and a light transmitting portion having a predetermined shape is provided. A light-shielding film having

As described above, by using the light-shielding film provided between the substrate and the photosensitive resin layer as a mask, it becomes possible to expose the substrate surface from an oblique direction on the substrate side. By performing the above-described exposure and the like, it is possible to form a plurality of concave portions or convex portions each of which is uniformly inclined in a certain direction with good controllability. Moreover, if a light-shielding film having a similar pattern shape is formed, a concave portion or a convex portion having substantially the same shape can be formed with good reproducibility. As a result, a photosensitive resin layer having an uneven surface gently inclined in a certain direction can be formed. Even when the light-shielding film is made of a metal thin film or the like, the second photosensitive resin layer is formed on the first photosensitive resin layer in the present invention, so that a short circuit between the reflection film and the light-shielding film can be prevented. Therefore, the second photosensitive resin layer also has a function as an insulating film.

According to a fourth aspect of the present invention, there is provided a reflecting plate according to any one of the first, second, and third aspects, wherein the reflecting plate is opposed to the reflecting plate. It is characterized by comprising a counter substrate, and a light modulation layer sandwiched between the reflector and the counter substrate.

According to the above construction, claims 1 and 2 are provided.
Alternatively, since the reflection plate is provided with the reflection plate according to any one of the third aspects, the reflection plate does not have a regular reflection surface that causes regular reflection of incident light. In general, reflection occurs on the surface of a counter substrate due to specular reflection of incident light. The reflection plate prevents the reflected light from being concentrated in the direction in which the reflection is visually recognized, and can reflect the light most in the viewing direction of the observer, for example, in the normal direction of the substrate. Therefore, the reflective display element provided with the reflective plate has a display screen which is bright and has good visibility.

According to a fifth aspect of the present invention, in the reflective display device according to the fourth aspect, the light modulation layer comprises a liquid crystal layer.

By providing a liquid crystal layer as a light modulation layer as described above, the present invention can be applied to a reflection type liquid crystal display device. Such a reflection type liquid crystal display element can realize a bright display screen with good visibility.

According to a sixth aspect of the present invention, there is provided a photosensitive resin layer provided on a substrate, and a reflective film provided on the photosensitive resin layer. A reflective plate, a counter substrate facing the reflector, and a light modulating layer sandwiched between the reflector and the counter substrate. Forming a photosensitive resin layer, and exposing the photosensitive resin layer to light by irradiating the photosensitive resin layer with light through a mask having a light transmitting portion having a predetermined shape from an oblique direction with respect to the substrate surface. Process, by developing the exposed photosensitive resin layer, a concave or convex portion having an asymmetric cross-sectional shape inclined in a certain direction, the uneven portion forming step of forming the photosensitive resin layer, By heat-treating the photosensitive resin layer, the concave or convex portions A heat treatment step of the curved and in the photosensitive resin layer, characterized in that it comprises a reflective film forming step of forming a light reflection of the reflection film.

According to the above method, by performing the above-described exposure step, a concave portion or a convex portion uniformly inclined in a certain direction can be formed with good controllability according to the shape of the mask. Moreover, if a light-shielding film having a similar pattern shape is formed, a concave portion or a convex portion having substantially the same shape can be formed with good reproducibility. As a result, it becomes possible to mass-produce a reflective display element provided with a reflector having substantially the same reflection and scattering characteristics.

According to a seventh aspect of the present invention, in the method of manufacturing a reflective display element according to the sixth aspect, prior to the resin layer forming step, a light shielding film is formed on the substrate so as to have a predetermined shape. Performing a light-shielding film forming step of forming a light-irradiating step from the back side of the substrate using the light-shielding film as a mask in the exposure step; Forming a photosensitive resin layer.

As described above, by using a light-shielding film provided between the substrate and the photosensitive resin layer as a mask, exposure can be performed from an oblique direction on the substrate side. Therefore,
Since it is not necessary to use a photomask for forming a concave portion or a convex portion in the photosensitive resin layer, it is possible to suppress a decrease in yield due to the conventional alignment between the photomask and the substrate. Therefore, an increase in cost can be suppressed.

Further, by forming another photosensitive resin layer on the photosensitive resin layer, the regular reflection surface between the concave portions or the convex portions in the photosensitive resin layer is formed into a gently inclined curved surface. Can be. Therefore, most of the incident light can be reflected not in the specular reflection direction but in the viewing direction of the observer. When the light shielding film is made of, for example, a metal thin film,
If the reflection film is formed directly on the photosensitive resin layer, the light-shielding film and the reflection film may be short-circuited. However, as described above, it is necessary to form another photosensitive resin layer on the photosensitive resin layer. Thus, the short circuit can be prevented. The material of the other photosensitive resin layer is not particularly limited as long as it is insulating, and may be the same material as the photosensitive resin layer or a different material.

According to an eighth aspect of the present invention, in the method of manufacturing a reflective display element according to the seventh aspect, in the exposing step, incident light incident from a predetermined direction is perpendicular to the substrate. In order to reflect light in a direction, light is emitted from a direction symmetrical with respect to the substrate surface with respect to the incident direction.

According to the above-described method, when light incident from a certain direction, for example, incident light most suitable for use, is desired to be reflected in the viewing direction of the observer, the incident direction of the incident light and the substrate Exposure may be performed from a direction that is symmetric with respect to. This makes it possible to easily manufacture a reflection plate having desired reflection characteristics.

According to a ninth aspect of the present invention, in order to solve the above-mentioned problems, a reflection plate having a reflection film provided on a substrate, a counter substrate facing the reflection plate, and a reflection plate are provided. And a light modulating layer sandwiched between a counter substrate and a method for manufacturing a reflective display element, the method comprising: forming a first resin layer on the substrate, forming a photosensitive resin layer on the substrate; An exposure step of exposing the photosensitive resin layer through a mask having a light transmitting portion of a predetermined shape from a linear direction, and developing the exposed photosensitive resin layer to have a symmetrical cross-sectional shape. Forming a plurality of recesses or protrusions in the photosensitive resin layer, and performing a heat treatment on the substrate to heat-treat the substrate so that the corners of the recesses or protrusions in the photosensitive resin layer are curved. Process and another photosensitive material having fluidity on the photosensitive resin layer. A second resin layer forming step of forming a resin layer, a heat treatment step of heat treating the other photosensitive resin layer while the substrate is tilted, and forming the reflective film on the other photosensitive resin layer. Forming a reflective film.

According to the above-mentioned method, a gently curved surface is formed by forming another photosensitive resin layer having fluidity on a photosensitive resin layer having a plurality of concave portions or convex portions having a symmetrical sectional shape. Is formed. Therefore, it is possible to form a reflector having no regular reflection surface between a plurality of concave portions or convex portions, and most of the light incident at a certain incident angle,
It is possible to manufacture a reflection plate that can reflect light in the direction of the viewer's view, for example, in the normal direction of the substrate.

According to a tenth aspect of the present invention, in the method of manufacturing a reflective display element according to the ninth aspect, in the exposing step, when the light irradiation is performed from the substrate side, The method may further include, before the one resin layer forming step, a light shielding film forming step of forming the light shielding film as the mask on the substrate so as to have a predetermined shape.

As in the above method, a photomask for forming a concave portion or a convex portion in the photosensitive resin layer is used by using a light-shielding film provided between the substrate and the photosensitive resin layer as a mask. Eliminates the need. As a result, it is possible to suppress a decrease in yield due to the conventional alignment between the photomask and the substrate. Therefore, an increase in cost can be suppressed.

When the light-shielding film is made of, for example, a metal thin film, if a reflection film is formed directly on the photosensitive resin layer provided on the substrate, there is a possibility of short-circuit between the light-shielding film and the reflection film. There is. Therefore, when a light-shielding film is used as a mask as in the present invention, another photosensitive resin layer having an insulating function is further provided on the photosensitive resin layer from the viewpoint of preventing short-circuit between the light-shielding film and the reflective film. Etc. must be formed. The material of the other photosensitive resin layer is not particularly limited as long as it is insulating, and may be the same material as the photosensitive resin layer or a different material.

[0032] According to an eleventh aspect of the present invention, in the method of manufacturing a reflective display element according to the seventh or eighth aspect,
The light-shielding film in the light-shielding film forming step is characterized by being formed together with a non-linear element for driving the light modulation layer and a wiring electrically connected to the non-linear element.

The light-shielding film may be essentially any thin film as long as it has light-shielding properties. Therefore,
As in the above method, if the same material as the nonlinear element and the wiring etc. electrically connected to the nonlinear element,
The non-linear element, the wiring, and the like can be formed at the same time without performing a separate step of forming a light-shielding film. Thereby, the increase in the number of manufacturing steps can be suppressed, and the light-shielding film can be easily formed.

[0034]

(Embodiment 1) Embodiment 1 of the present invention will be described below with reference to FIGS. However, parts unnecessary for description are omitted, and some parts are shown enlarged or reduced for ease of description. The above applies to the following drawings.

FIG. 1 is a schematic sectional view showing a main part of the reflective liquid crystal display element according to the first embodiment. FIG. 2 is a plan view schematically showing one pixel of the reflective liquid crystal display device. As shown in FIG. 1, the reflection type liquid crystal display element includes a reflection plate 1, a counter substrate 2 (display surface side), and a liquid crystal layer as a light modulation layer sandwiched between the reflection plate 1 and the counter substrate 2. And 3.

The reflecting plate 1 is provided on a glass substrate 11 with T
FT (Thin Film Transistor) 4
, An insulating film 5, a light-shielding film 7, a photosensitive resin layer 9, a reflective film 10, and an alignment film 12.

On the glass substrate 11, the TFT 4
And an insulating film 5 are formed. The light shielding film 7 is formed on the insulating film 5. Further, the above TFT4,
The photosensitive resin layer 9 is formed on the insulating film 5 and the light shielding film 7. On the photosensitive resin layer 9, a reflection film 10 is formed along the shape of the photosensitive resin layer 9. Further, an alignment film 12 is formed on the reflection film 10.

The TFT 4 comprises an insulating film 5 and an amorphous silicon film (hereinafter a-
Abbreviated as Si film. ) 14, and three electrodes of a gate electrode 6g, a source electrode 6s, and a drain electrode 6d. The insulating film 5 is made of, for example, SiO ₂
An insulating film made of The gate electrode 6g is provided on the glass substrate 11 and has a gate line 21 shown in FIG.
Is electrically connected to The a-Si film 14 is a semiconductor layer formed so as to be located on the gate electrode 6g with the insulating film 5 interposed therebetween, and patterned into a predetermined shape. The source electrode 6s is electrically connected to the source lines 22 forming the wiring pattern by being patterned into a predetermined shape. The drain electrode 6d is electrically connected to the reflection film 10 via a contact hole 20 provided in the photosensitive resin layer 9.

The light shielding film 7 is a metal thin film having a light shielding property,
For example, it is made of aluminum. In addition, the light shielding film 7 has
As shown in FIG. 3, circular light transmitting portions 8 having a diameter of about 6 to 10 μm are provided at random in a region where elements such as wiring and TFT 4 are not formed. The shape of the light transmitting portions 8 is not limited to the circular shape described above, and may be any shape.

The photosensitive resin layer 9 is made of, for example, an acrylic positive resist agent (manufactured by Nippon Gosei Co., Ltd.). The surface of the photosensitive resin layer 9 has a fine uneven surface,
The positions of the concave and convex surfaces are random. Moreover,
The uneven surface is inclined at an inclination angle ψ of about 19.5 degrees in the downward direction (X ′ direction) of the display screen with respect to the normal line of the glass substrate 11 (see FIG. 3). Therefore, there is no plane parallel to the glass substrate 11, that is, a regular reflection plane. The area ratio between the concave surface and the convex surface is almost the same. Further, the maximum thickness of the photosensitive resin layer 9 is, for example, about 3 μm. On the other hand, the concave portion having the smallest thickness has a thickness of about 1 μm. The reason why the concave surface has the predetermined thickness is to prevent a short circuit between the reflection film 10 and the light shielding film 7.

The reflection film 10 is made of a light-reflective metal thin film, for example, Al. Further, at least a region of the reflection film 10 on which the uneven surface is formed functions as a pixel electrode. As a material of the reflection film 10, in addition to the Al, silver (Ag), chromium (Cr), nickel (Ni)
And a multilayer film in which a plurality of metal thin films are stacked.
The thickness of the reflection film 10 is 0.2 μm to 0.4 μm.
It is about.

The alignment film 12 is made of, for example, a polyimide resin and aligns nearby liquid crystal molecules in a predetermined direction.

On the counter substrate 2, a transparent electrode 15 made of indium tin oxide (ITO) is formed.
Is provided. The counter substrate 2 is not particularly limited, but in this embodiment, the same material as the glass substrate 11 is used.

The liquid crystal layer 3 comprises a guest-host liquid crystal in which a black dichroic dye is dissolved in a chiral nematic liquid crystal.

Next, a method of manufacturing the reflection type liquid crystal display device according to the present embodiment will be described. FIG.
FIG. 6 is a schematic cross-sectional view for explaining the manufacturing process of FIG.

First, as shown in FIG. 4A, a gate electrode 6g, an insulating film 5, and an a-Si film 14 are formed on a glass substrate 11 by a conventionally known method. Further, an aluminum thin film is formed on the insulating film 5 so as to have a thickness of 200 nm by, for example, a sputtering method. continue,
The source electrode 6s, the drain electrode 6d, and the light-shielding film 7 are formed by patterning the aluminum thin film into a predetermined shape by photolithography and etching (light-shielding film forming step). Here, the light-shielding film 7 is patterned such that circular light-transmitting portions 8 having a diameter of about 6 to 10 μm are randomly provided in a region where there are no wires or elements. In order to form the light shielding film 7 having the above shape,
It is only necessary to add the pattern shape of the light shielding film 7 to the photomask used in the photolithography method,
Therefore, it is not necessary to newly increase the number of masks.

Next, as shown in FIG.
An acrylic positive resist agent is applied on T4, the insulating film 5, and the light-shielding film 7 with a spinner or the like to form a first photosensitive resin layer 19 having a thickness of 2 μm (resin layer forming step).
Subsequently, ultraviolet light is exposed from the first photosensitive resin layer 19 side via a photomask 31 provided with a light transmitting portion at a position corresponding to the drain electrode 6d. Further, using the light-shielding film 7 as a mask, ultraviolet light is exposed from a direction on the glass substrate 11 side which is inclined by 30 degrees with respect to a normal to the glass substrate 11 (exposure step). Thereby, the depth direction of the concave portion 19 a in the first photosensitive resin layer 19 can be formed so as to be inclined with respect to the normal line of the glass substrate 11. Here, the concave portion 19a
Becomes smaller than 30 degrees with respect to the glass substrate 11. This is because the refractive index (for example, about 1.5) of the glass substrate 11 is larger than the refractive index (1.0) of air, so that when the ultraviolet light traveling along the path V1 enters the glass substrate 11, it is refracted, This is because the traveling direction is changed to the route V2. Therefore, actually, ultraviolet rays having an incident angle of 19.5 degrees are irradiated according to Fresnel's law.

For reference, if ultraviolet rays are to be exposed from an oblique direction, a method of exposing the ultraviolet rays from the first photosensitive resin layer 19 side through a normal photomask may be considered. However, such a method has a disadvantage that it is difficult to form a desired pattern.
That is, an ordinary exposure machine performs exposure while keeping the substrate and the photomask horizontal, and uses the light so as to be incident perpendicularly to the substrate. Therefore, the exposure machine is not used on the assumption that the exposure is performed in an oblique direction in the above state. In particular, in a projection type exposure apparatus, when the light is irradiated from an oblique direction, the focal point is focused only on a part of the substrate surface. Therefore, the other region out of focus cannot be exposed to ultraviolet rays in accordance with the shape of the light transmitting portion in the photomask, and cannot be patterned into a desired shape. However, in the present embodiment, the light-shielding film 7 provided between the glass substrate 11 and the first photosensitive resin layer 19 is used as a mask. Thus, a desired pattern can be easily formed.

Further, in the method of manufacturing a reflective display element according to the present invention, the technical idea does not exclude a contact exposure method in which a photomask and a substrate are brought into close contact with each other for exposure. Even if this method is adopted, it is possible to form the first photosensitive resin layer 19 having fine concave portions. However, the exposure from the back surface as described above is excellent in that the photomask and the glass substrate 11 come into contact with each other, and thus the photomask and the glass substrate 11 are liable to have foreign matters and scratches. In addition, in the exposure process using a photomask, strict accuracy requirements are required when the photomask and the glass substrate 11 are aligned, which has been a cause of a decrease in yield. The decrease in the yield can be suppressed. Therefore, an increase in cost can be suppressed. It is also possible to adopt a proximity exposure method in which exposure is performed with the distance between the photomask and the glass substrate 11 reduced. In this method, contact between the photomask and the glass substrate 11, which is a problem in contact exposure, can be avoided. However, it is necessary to consider the distance between the photomask and the glass substrate 11 within a range where pattern formation is possible. is there.

Subsequently, after the above-mentioned exposure step, the exposed first photosensitive resin layer 19 is developed with a developing solution or the like (a step of forming uneven portions). Thereby, as shown in FIG. 4C, a contact hole 20 'whose depth direction coincides with the normal direction of the glass substrate 11 is formed in the portion where the drain electrode 6d is located. On the other hand, in a region of the first photosensitive resin layer 19 where wirings, TFTs 4 and the like are not located, a plurality of inclined portions whose depth direction is inclined at 19.5 degrees with respect to a normal line of the glass substrate 11 are formed. Is formed.

Next, in order to optimize the reflection / scattering characteristics of the reflection film, it is necessary to make the corner in the concave portion 19a a smooth curved surface. In the present embodiment, the concave portion 19a
Was made a smooth curved surface by, for example, heat treatment at 180 degrees (heat treatment step). Here, the temperature of the heat treatment is 130 ° C.
It is preferable that it is in the range of -200 ° C. Furthermore, as described above, simply performing the heat treatment to round the corners of the concave portion 19a causes the angle of the inclined surface in the depth direction to be too large.
As shown in FIG. 4D, a second photosensitive resin layer 29 made of the same material as the first photosensitive resin layer 19 is applied on the first photosensitive resin layer 19 (second resin layer forming step). .

Next, by performing the same process as that for opening the contact hole 20 ′, the position corresponding to the drain electrode 6 d is opened again, and the contact hole 2 ′ is opened.
0 is formed.

Subsequently, the second photosensitive resin layer 29 is heated in an oven at a temperature at which heat sagging of the second photosensitive resin layer 29 does not significantly occur, for example, at 130 ° C. for 3 hours to cure the second photosensitive resin layer 29. Thereby, the photosensitive resin layer 9 having a large number of fine uneven surfaces is formed.

Further, as shown in FIG. 4F, a reflective film 10 is formed on the photosensitive resin layer 9 by evaporating aluminum so as to have a thickness of 200 nm. ). Here, short circuit between the light shielding film 7 and the reflection film 10 is prevented by the presence of the second photosensitive resin layer 29. Next, a polyimide resin is applied on the reflective film 10 and a rubbing treatment or the like is performed to form an alignment film 12.

On the other hand, a transparent electrode 15 is formed on the counter substrate 2 by a conventionally known method, and an alignment film 12 is formed on the transparent electrode 15 in the same manner as described above.

Subsequently, the glass substrate 11 and the opposite substrate 2
Then, a guest-host liquid crystal in which a black dichroic dye is dissolved in a chiral nematic liquid crystal is injected from a liquid crystal injection port to form a liquid crystal layer 3. As described above, the reflective liquid crystal display device according to the present embodiment can be manufactured.

Next, the principle of operation of a reflective display obtained by connecting a normal driving circuit (not shown) and the like to the reflective liquid crystal display device manufactured as described above will be described. FIG. 5 is a schematic cross-sectional view for explaining a light reflection / scattering state in the reflective display. FIG.
4 is a graph showing reflection / scattering characteristics in the reflective display.

In the above-mentioned reflection type display, when a voltage is applied by a drive circuit or the like, the display screen becomes white display, and when no voltage is applied, the display screen becomes black display. Here, the reflection characteristics of the reflection type display when a voltage is applied will be considered.

For example, as shown in FIG.
Light traveling in a vertical plane to the glass substrate 11
Incident angle α = −30 from the top of the display screen with respect to the normal
Consider the case where the light is incident on a reflective display in degrees. The light incident at an incident angle α = −30 degrees is incident on the counter substrate 2 because the refractive index (for example, about 1.5) of the counter substrate 2 is larger than the refractive index (1.0) of air. When it is refracted (see FIG. 6). Therefore, the incident angle of the incident light that reaches the reflective film 10 is actually small. When this incident light passes through the liquid crystal layer 3 and reaches the reflective film 10, the incident light is scattered and reflected mainly in the normal direction of the glass substrate 11 by the reflective film 10. Further, the reflected light is modulated by the liquid crystal layer 3 and emitted from the reflective display. Even if the incident light enters the reflective display at an angle smaller than 30 degrees, it is mainly scattered and reflected in the normal direction of the glass substrate 11 for the following reason. That is, as described above, the recess is formed in the glass substrate 1.
It is formed by exposing the back surface from an oblique direction of 30 degrees on one side. However, since the ultraviolet rays are actually refracted when entering the glass substrate 11, the concave portions are inclined at an angle slightly smaller than 30 degrees with respect to the substrate surface. Therefore, in practice, the light has a characteristic of scattering and reflecting light incident at an incident angle smaller than 30 degrees in the normal direction of the glass substrate 11.

Here, the reflectance at the time of applying a voltage between the reflective display for comparison having a reflector having a convex portion having a symmetrical cross-sectional shape and the reflective display according to the present embodiment. Was measured for angle dependence. The reflective display for comparison was produced as follows. That is, in the method of manufacturing the reflective film 10 according to the present invention, the glass substrate 11 on the glass substrate 11 side was exposed to ultraviolet light obliquely at an angle of 30 degrees using the light shielding film 7 as a mask. UV light was exposed from the vertical direction for the reflective display for use. Regarding the other steps, a reflective display for comparison was produced in the same manner as described above.

FIG. 7 is a graph showing the reflection and scattering characteristics of the comparative display manufactured as described above and the reflective display according to the present embodiment. The measuring method is as follows. That is, assuming that the normal line on the glass substrate 11 is 0 degree, the light is incident at an incident angle of −30 degrees from the upper direction of the display screen, and the luminance of the emitted light when applying a voltage is varied while changing the emitted angle θ. It was measured with a luminance meter. As a result, as is apparent from FIG. 7, the reflectance of the reflective display for comparison (curve B) peaks when the emission angle is +30 degrees, and the luminance of the reflected light is the highest. This is for the following reasons. That is, the reflective plate in the reflective display for comparison includes:
Since there is a specular reflection surface parallel to the substrate surface, light incident at -30 degrees is specularly reflected at +30 degrees. On the other hand, light that is specularly reflected by the opposite substrate is also reflected at a reflection angle of +30 degrees, and thus overlaps with light emitted from the reflective display, resulting in poor visibility of the display screen. Therefore, the observer tends to observe the reflective display while avoiding the specular reflection direction having poor visibility. In contrast, in the reflective display according to the present embodiment,
As shown by the curve A, when the emission angle is 0 degree, that is, on the normal line of the display screen, the reflectance peaks, and it can be seen that the brightness of the reflected light is the highest. This is because most of the light reflected by the reflection film 10 is emitted in the normal direction of the glass substrate 11. Usually, the observer looks at the display screen from the normal direction of the display screen, but the reflectance Rf2 in the normal direction of the reflective display according to the present embodiment is the reflectance of the reflective display for comparison. It is about three times that of Rf1, and it can be seen that the luminance is significantly improved and the visibility is improved.

Accordingly, in the reflective display according to the present embodiment, the inclination axis S of the uneven surface of the photosensitive resin layer 9
Is tilted downward (X ′ direction) of the display screen from the normal line of the glass substrate 11 so that the illumination light incident from above the observer's head is directed in a direction close to the normal direction of the display screen. Can be reflected. On the other hand, as for light that is going to be incident on the reflective display from below the display screen, since the lower part of the display screen is facing the foot of the observer, it is smaller than the light coming from above the display screen (X direction). The light amount is inherently small. Therefore, if the tilt axis S is tilted in the upward direction of the display screen with respect to the normal line of the glass substrate 11 and the setting is opposite to that in the present embodiment, the display becomes darker than the reflective display for comparison. If the display screen is tilted in one of the left and right directions, brightness and the like are not harmonized on the left and right sides of the display screen, and the observer feels uncomfortable. Therefore, it is preferable that the tilt axis S be tilted downward in the display screen rather than the normal line of the glass substrate 11, whereby the illumination light can be used more efficiently.

As described above, in the reflective display according to the present embodiment, the surface of the reflective film has a smooth downward slope from the opening edge of the recess toward the bottom in the downward direction of the display screen. By forming a plurality of fine concave portions having a gentle inclined surface, it was possible to improve the reflection / scattering characteristics of the reflection film. As a result, the efficiency of using the illumination light can be improved, and a brighter display than the conventional reflective display can be realized.

Further, according to the method of manufacturing the reflection type liquid crystal display device according to the present embodiment, when forming the TFT and the like, the light shielding layer 7 is formed together with the wiring and the back surface is exposed, so that the photosensitive resin layer 9 is formed. Since the concave portion is formed, the number of photomasks for forming the concave portion can be reduced. As a result, it is possible to suppress a decrease in the yield due to the alignment between the photomask and the glass substrate 11, and the like. In addition, according to the manufacturing method of the present embodiment, the controllability is excellent such that the concave portion in the reflection plate 1 can be formed in a desired shape, and the reproducibility is excellent such that the concave portion of the same shape can be formed. .

(Embodiment 2) Embodiment 2 of the present invention will be described with reference to FIG. Note that components having the same functions as those of the reflective liquid crystal display device according to the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

The reflection type liquid crystal display device according to the second embodiment has substantially the same configuration as the reflection type liquid crystal display device according to the first embodiment. On the other hand, the difference is that the photosensitive resin layer is exposed on the back surface from the normal direction, and another photosensitive resin layer having fluidity is formed on the photosensitive resin layer.

FIG. 8 is a schematic cross-sectional view for explaining a manufacturing process of the reflective liquid crystal display device according to the present embodiment. First, in the same manner as in the first embodiment, the first photosensitive resin layer 19 is applied on the TFT 4 and the light shielding film 7 provided on the glass substrate 11 (first resin layer forming step), and the photomask 3 is formed.
In step 1, ultraviolet light is exposed from the first photosensitive resin layer 19 side (see FIG. 8A). Next, from the back side of the glass substrate 11, the first
The photosensitive resin layer 19 is exposed to ultraviolet rays for exposure (exposure step).

Subsequently, a contact hole 20 'and a concave portion 19a having a symmetrical cross section can be formed by performing a developing step with a developing solution.

Further, in order to round the corner of the concave portion 19a in the first photosensitive resin layer 19, for example, a heat treatment of 180 degrees is performed (heat treatment step). Next, an acrylic photosensitive resin is dissolved in a solvent (for example, diethylene glycol monomethyl ether) to prepare a coating solution diluted so that the concentration of the acrylic photosensitive resin is doubled. Here, the dilution ratio with the solvent may be appropriately set according to the viscosity of the photosensitive resin and the like, and is not particularly limited. Subsequently, the coating solution is applied onto the first photosensitive resin layer 19,
Apply at a low speed of 200 rpm with a spinner,
The photosensitive resin layer 29 is formed (second resin layer forming step, see FIG. 8C). The conditions for coating with a spinner are not particularly limited, and the rotation speed and the like may be set according to the viscosity and the film thickness of the coating solution.

Subsequently, as shown in FIG. 8D, the glass substrate 11 is heat-treated at 80 ° C. for 20 minutes in an oven with one end of the glass substrate 11 raised at approximately ω = 50 degrees from the horizontal direction (heat treatment step). ). Thereby, the solvent in the second photosensitive resin layer 29 can be evaporated. At this stage,
A resin layer with a somewhat smooth curved surface can be formed,
In order to smoothly incline the surface of the concave portion downwardly and gently in the downward direction of the display screen, in the present embodiment, the second
The glass substrate 11 is tilted before the photosensitive resin layer 29 dries. As described above, since the material of the second photosensitive resin layer 29 is made of the photosensitive resin diluted with the solvent, the material is inherently high in fluidity. Therefore, the second photosensitive resin layer 29 can be caused to flow in the Y direction by the action of gravity. This makes it possible to form the photosensitive resin layer 9 having an asymmetric cross section and a fine uneven surface.

Further, in the same manner as in the first embodiment, after opening the contact hole 20, the photosensitive resin layer 9 is formed.
A reflective film 10 is formed by evaporating aluminum thereon, and an alignment film 12 is formed on the reflective film 10.

On the other hand, the transparent electrode 15 and the alignment film 12 are also formed on the counter substrate 2 in the same manner as in the first embodiment. Subsequently, after bonding the glass substrate 11 and the opposing substrate 2, a guest-host liquid crystal in which a black dichroic dye is dissolved in a chiral nematic liquid crystal is injected from a liquid crystal injection port to form a liquid crystal layer 3. Thereby, the reflection type liquid crystal display element according to the present embodiment can be manufactured.

Further, in the same manner as in the first embodiment, a reflection type display obtained by connecting a normal driving circuit or the like to the reflection type liquid crystal display element was manufactured. As a result, similar to the first embodiment, the use of the reflection plate 1 having excellent reflection and scattering characteristics can improve the utilization efficiency of the illumination light, and can provide a brighter display than the conventional reflection type display. A possible reflective display can be provided.

As described above, the method of manufacturing the reflection type liquid crystal display element according to the present embodiment uses the light shielding film 7 as a mask.
Since the concave portion 19a is formed in the first photosensitive resin layer 19 by exposing the back surface from the vertical direction of the glass substrate 11, there is no need to perform an exposing step using a photomask. As a result, it is possible to reduce the number of photomasks for forming the concave portions 19a, and it is possible to suppress a decrease in yield due to, for example, the alignment between the photomask and the glass substrate 11. Moreover, the second photosensitive resin layer 29 having high fluidity is
Since it is applied on the first photosensitive resin layer 19 having the concave portion 19a and the glass substrate 11 is inclined, it is possible to manufacture a reflecting plate having the same reflection and scattering characteristics as in the first embodiment.

(Other Matters) The dimensions, materials, shapes, relative arrangements, and the like of the photosensitive resin layer, which is a main component of the present invention, described in each of the above embodiments are particularly limited. Unless otherwise stated, the scope of the present invention is not intended to be limited thereto, but is merely illustrative.

For example, in each of the above embodiments, the case where the area ratio of the concave surface and the convex surface on the surface of the photosensitive resin layer is almost the same has been described, but the present invention is not limited to this. Absent. That is, in the present invention, the ratio of the area occupied by the concave surface to the surface of the photosensitive resin layer may be large, or vice versa. Further, in each of the above embodiments, the case where the shape of the photosensitive resin layer is circular when viewed in a plan view from the normal direction of the substrate has been described, but the present invention is not limited to this. Not something. Specifically, for example, as shown in FIG. 9, by adopting a light-shielding film having light transmitting portions of various shapes, it is possible to form a photosensitive resin layer according to the shape. In addition, the photosensitive resin layer having various shapes uniformly inclined in a desired direction can be obtained by performing the method of manufacturing a reflective display element according to the present invention, regardless of the shape as shown in FIG. Can be formed.

In each of the above embodiments, formation of the first photosensitive resin layer having a plurality of fine projections or depressions by the method described below is also conceivable. That is, after the first photosensitive resin layer is formed, the glass substrate is subjected to a heat treatment in a state where the glass substrate is tilted or made vertical, so that the fluidity of the first photosensitive resin layer is increased, and heat is dripped downward by the action of gravity. It is a way to make it. However, in the case of the above method, although the fluidity of the first photosensitive resin layer can be increased by the heat treatment, the first photosensitive resin layer is inherently highly viscous, and the first photosensitive resin layer has an actual surface tension effect. The inventors of the present application have confirmed that it is difficult to form a gently inclined surface. Moreover, depending on the temperature distribution and the like generated during the heat treatment,
It is difficult to form a uniform concave or convex part, and it is also difficult to form with good reproducibility. Therefore, it is difficult to obtain a reflector having the same scattering / reflection characteristics. Furthermore, since a regular reflection surface parallel to the substrate surface exists between the inclined concave portion and the convex portion, a part of the incident light is reflected in the regular reflection direction. Therefore, light cannot be strongly reflected only in the viewing direction of the observer.

Here, the angle dependence of the reflectance was measured in the same manner as in the first embodiment for the reflection type display having the reflection plate formed by the heat sagging as described above. The result is shown by curve C in FIG. As is clear from FIG. 7, it can be seen that the reflectance peaks when the emission angles are 0 degree and +30 degrees. Further, the reflectance Rf3 when the emission angle is 0 degree is smaller than the reflectance Rf2 of the reflective display according to the first embodiment. Therefore, in order to control the reflection and scattering characteristics of the reflector so that the luminance in the viewing direction of the observer, that is, on the normal to the display screen, is maximized, the reflector according to the present invention is more preferable. Is clear.

Further, in the method of manufacturing the reflection type liquid crystal display element in each of the above embodiments, the first photosensitive resin layer 1
9, the contact hole 20 ′ is formed, the second photosensitive resin layer 29 is formed, and then the contact hole 20 is formed again. This is because heat treatment for rounding the corners of the concave portions formed in the photosensitive resin layer 19 is performed to solidify the photosensitive resin layer 19 and form the contact holes 20 together with the second photosensitive resin layer 29. Is difficult. However, when performing the above heat treatment, if the temperature is set within a range in which the corners of the concave portion in the first photosensitive resin layer 19 are rounded and the opening by exposure is possible, the second photosensitive resin layer 19 The first photosensitive resin layer 19 can be opened together with the opening 29, so that the manufacturing process can be simplified.

Further, in each of the above embodiments, the case where the liquid crystal layer is used as the light modulating layer has been described. However, the present invention relates to a light receiving element having a light reflecting reflector on the back surface. Well, it is not particularly limited.

In each of the above embodiments, the case where the incident angle is 30 degrees has been described in accordance with the most preferred embodiment of the present invention. The value of the angle can be varied. Here, from the viewpoint of effective use of incident light, the incident angle is preferably in the range of 20 to 60 degrees.

Further, in each of the above-described embodiments, the mode in which the uneven surface of the photosensitive resin layer is uniformly inclined in a certain direction, that is, from the upper part to the lower part of the display screen has been described. However, the present invention is not limited to this. For example, the display area may be divided into a plurality of areas, and the inclination angle may be different for each area. In the present invention, since the photosensitive resin layer is exposed from a direction oblique to the substrate surface through a mask having a light transmitting portion of a predetermined shape, the inclination angle is changed for each region, or the inclination direction is changed. Can be easily implemented. Specifically, FIGS. 10A and 10B
11A and 11B, the exposure direction may be changed for each region of one pixel, using the masks 32a and 32b shown in FIG. By doing as described above, it is possible to make the reflection characteristics different for each area in the display area.

[0083]

The present invention is embodied in the form described above and has the following effects.

In the reflection plate according to the present invention, since the reflection film is provided on the photosensitive resin layer having a plurality of uneven surfaces inclined in a certain direction, there is no regular reflection surface parallel to the substrate surface. Therefore, most of the light incident at a certain incident angle can be reflected in the viewing direction of the observer, for example, in the normal direction of the substrate. Thereby, the utilization efficiency of the incident light can be improved, and the effect of being able to be reflected brightly in a direction within a predetermined angle range is achieved.

In the reflection type display device according to the present invention, since the reflection film is formed on the photosensitive resin layer having the gently inclined uneven surface, the regular reflection surface which causes regular reflection of incident light is provided. It is not formed. Therefore, a direction different from the specular reflection direction in which reflection occurs due to specular reflection on the surface of the opposing substrate, for example, the normal direction of the substrate can be displayed brightest. Thereby, there is an effect that a reflective display element which is bright and has good visibility can be provided.

Further, according to the method of manufacturing a reflective display element according to the present invention, a photosensitive resin layer having an uneven surface uniformly inclined in a certain direction can be formed with good controllability.
Also, if a light-shielding film having a similar pattern shape is formed,
Since the concave and convex portions having substantially the same shape can be formed with good reproducibility, a reflective display element including a reflective plate having similar reflection and scattering characteristics can be mass-produced. Furthermore, if a non-linear element for driving the light modulation layer and a light-shielding film formed together with wiring electrically connected to the non-linear element are used as the mask, the number of photomasks can be reduced.
This has the effect of suppressing a decrease in yield due to the alignment between the photomask and the substrate.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view schematically showing a reflective liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a plan view schematically showing the reflective liquid crystal display element according to the first embodiment.

FIG. 3 is a schematic sectional view showing a main part of the reflective display element according to the first embodiment.

FIG. 4 is a schematic cross-sectional view showing a step of manufacturing the reflective liquid crystal display element according to the first embodiment.

FIG. 5 is a perspective view showing a traveling direction of incident light and reflected light in the reflective liquid crystal display element according to the first embodiment.

FIG. 6 is a partial cross-sectional view showing a light scattering / reflecting state in the reflective liquid crystal display device according to the first embodiment.

FIG. 7 is a graph showing light reflection / scattering characteristics of the reflection type liquid crystal display device according to the first embodiment.

FIG. 8 is a schematic cross-sectional view showing a step of manufacturing the reflective liquid crystal display element according to Embodiment 2 of the present invention.

FIG. 9 is a plan view schematically showing another light shielding film according to the present invention.

FIG. 10 is a plan view schematically showing another mask according to the present invention.

FIG. 11 is a schematic sectional view showing a part of the manufacturing process of the reflective liquid crystal display element according to the present invention.

FIG. 12 is a schematic cross-sectional view showing a manufacturing process of a conventional reflective liquid crystal display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reflector 2 Counter substrate 3 Liquid crystal layer (light modulation layer) 4 TFT (non-linear element) 7 Shielding film 8 Light transmission part 9 Photosensitive resin layer 10 Reflection film 11 Glass substrate (substrate) 20 Contact hole 19 First photosensitive resin Layer 19a Depression 29 Second photosensitive resin layer 31 Photomask

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Mariko Kawaguri 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Takeshi Karasawa 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture F-term (reference) 2H042 DA01 DA02 DA03 DA04 DA11 DA17 DC02 DC08 DD01 DE00 2H091 FA14Y FA31Y FA34Y FB04 FB08 FC02 FC10 FC22 FC25 FD01 GA03 GA13 HA08 LA16

Claims (11)

[Claims] 1. A reflector having a photosensitive resin layer provided on a substrate and a reflective film provided on the photosensitive resin layer, wherein the surface of the photosensitive resin layer has an uneven surface. And a concave or convex portion forming the concave / convex surface, the cross-sectional shape of which is inclined in a certain direction, and has a structure in which reflected light is reflected in a specific direction. 2. A reflection plate having a photosensitive resin layer provided on a substrate and a reflection film provided on the photosensitive resin layer, wherein the photosensitive resin layer is formed on the substrate. A first photosensitive resin layer formed by exposing the photosensitive resin material to the substrate surface from a diagonal direction through a mask through a mask and developing the photosensitive resin material. The first having a plurality of concave portions or convex portions having an asymmetrical cross-sectional shape inclined in the direction
A photosensitive resin layer, and a second photosensitive resin layer provided on the first photosensitive resin layer so as to conform to the shape of the first photosensitive resin layer. Reflector. 3. The reflector according to claim 2, wherein the mask is a light-shielding film provided between the substrate and the photosensitive resin layer and having a light transmitting portion having a predetermined shape. 4. The reflector according to claim 1, 2 or 3, a counter substrate facing the reflector, and light sandwiched between the reflector and the counter substrate. A reflective display device comprising a modulation layer. 5. The reflection type display device according to claim 3, wherein said light modulation layer comprises a liquid crystal layer. 6. A reflecting plate including a photosensitive resin layer provided on a substrate, and a reflecting film provided on the photosensitive resin layer; an opposing substrate facing the reflecting plate; In a method of manufacturing a reflective display element including a reflective plate and a light modulation layer sandwiched between a counter substrate, a resin layer forming step of forming a photosensitive resin layer on the substrate, An exposure step of irradiating the photosensitive resin layer with light through a mask having a light transmitting portion of a predetermined shape and exposing the same from an oblique direction, and developing the exposed photosensitive resin layer. Forming a concave or convex portion having an asymmetric cross-sectional shape inclined in a certain direction, a step of forming a concave and convex portion on the photosensitive resin layer, and heat-treating the photosensitive resin layer to form the concave or convex portion. A heat treatment step of turning the corners into a curved surface, and the photosensitive resin Above, the manufacturing method of the reflection type display device which comprises a reflective film forming step of forming a light reflection of the reflection film. 7. A light-shielding film forming step of forming a light-shielding film so as to have a predetermined shape on the substrate before the resin layer forming step. In the exposing step, the light-shielding film is used as a mask.
The reflection type according to claim 6, wherein light irradiation is performed from the back side of the substrate, and further, after the heat treatment step, a step of forming another photosensitive resin layer on the photosensitive resin layer is performed. A method for manufacturing a display element. 8. In the exposing step, in order to reflect incident light incident from a predetermined direction in a direction perpendicular to the substrate, light is emitted from a direction symmetrical to the incident direction with respect to the substrate surface. The method of manufacturing a reflective display element according to claim 7, wherein irradiation is performed. 9. A reflection type display comprising: a reflection plate having a reflection film provided on a substrate; a counter substrate facing the reflection plate; and a light modulation layer sandwiched between the reflection plate and the counter substrate. In the method for manufacturing an element, a first resin layer forming step of forming a photosensitive resin layer on the substrate, and a mask having a light transmitting portion having a predetermined shape from a normal direction of the substrate. An exposure step of exposing the photosensitive resin layer; and developing the exposed photosensitive resin layer to form a plurality of recesses or projections having a symmetrical cross-sectional shape on the photosensitive resin layer. A forming step, a heat treatment step of subjecting the substrate to a heat treatment to make the corners of the concave or convex portions in the photosensitive resin layer a curved surface, and another photosensitive material having fluidity on the photosensitive resin layer. Forming a second resin layer for forming a conductive resin layer, and tilting the substrate. A reflection-type display comprising: a heat treatment step of heat-treating the other photosensitive resin layer in a state where the reflection film is formed; and a reflection film forming step of forming the reflection film on the other photosensitive resin layer. Device manufacturing method. 10. When irradiating light from the substrate side in the exposing step, before the first resin layer forming step,
10. The method according to claim 9, further comprising the step of forming a light-shielding film as the mask so as to have a predetermined shape on the substrate. 11. The light-shielding film in the light-shielding film forming step is formed together with a nonlinear element for driving the light modulation layer and a wiring electrically connected to the nonlinear element. 11. The method for manufacturing a reflective display element according to claim 7 or 10.