JP3783379B2 - Diffusion reflector manufacturing method and reflective display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reflective display device. More specifically, the present invention relates to a diffusive reflector incorporated in a reflective display device and a manufacturing method thereof.
[0002]
[Prior art]
An example of a conventional reflective display device will be briefly described with reference to FIG. This is a reflective guest-host liquid crystal display device, which is disclosed, for example, in JP-A-6-222351. The display device 301 includes a pair of front and rear substrates 302 and 303, a guest host liquid crystal layer 304, a dichroic dye 305, a pair of front and rear transparent electrodes 306 and 310, a pair of front and rear alignment layers 307 and 311, a mirror-like light reflecting layer 308, A quarter-wave plate layer 309 is included. The pair of substrates 302 and 303 are made of an insulating material such as glass, quartz, or plastic. At least the front substrate 302 located on the incident side is transparent. A guest-host liquid crystal layer 304 containing a dichroic dye 305 is held in the gap between the pair of substrates 302 and 303. The guest-host liquid crystal layer 304 includes nematic liquid crystal molecules 304a, and the dichroic dye 305 is a so-called p-type dye having a transition dipole moment substantially parallel to the long axis of the molecule. Although not shown, switching elements are integrated on the inner surface 302a of the front substrate 302. The transparent electrode 306 is patterned in a matrix form as a pixel electrode and is driven by a corresponding switching element. Further, the inner surface of the front substrate 302 is covered with an alignment layer 307 made of polyimide resin or the like. The surface of the alignment layer 307 is subjected to, for example, a rubbing process, and nematic liquid crystal molecules 304a are horizontally aligned. On the other hand, a specular light reflecting layer 108 made of aluminum or the like and a quarter-wave plate layer 309 made of polymer liquid crystal or the like are formed in this order on the inner surface 303a of the rear substrate 303 located on the reflecting side. ing. Further, on the quarter-wave plate layer 309, a transparent electrode 310 serving as a counter electrode and an alignment layer 311 are formed in this order.
[0003]
Next, the operation when performing monochrome display using the reflection type guest host liquid crystal display device 301 will be briefly described. When no voltage is applied, the nematic liquid crystal molecules 304a are horizontally aligned, and the dichroic dye 305 is similarly aligned. When light incident from the front substrate 302 side proceeds to the guest-host liquid crystal layer 304, a component having a vibration plane parallel to the major axis direction of the molecule of the dichroic dye 305 is included in the incident light. Is absorbed by. Further, a component having a vibration plane perpendicular to the long axis direction of the molecule of the dichroic dye 305 passes through the guest-host liquid crystal layer 304 and forms a quarter wavelength formed on the surface 303a of the rear substrate 303. The plate layer 309 makes circularly polarized light, and the light reflecting layer 308 specularly reflects it. At this time, the polarized light of the reflected light is reversed, passes through the quarter-wave plate layer 309 again, and becomes a component having a vibration plane parallel to the major axis direction of the molecule of the dichroic dye 305. Since this component is absorbed by the dichroic dye 305, a complete black display is obtained. On the other hand, when a voltage is applied, the nematic liquid crystal molecules 304a are vertically aligned along the electric field direction, and the dichroic dye 305 is similarly aligned. Light incident from the front substrate 302 passes through the guest-host liquid crystal layer 304 without being absorbed by the dichroic dye 305, and is further reflected by the light reflection layer 308 without being affected by the quarter-wave plate layer 309. reflect. The reflected light again passes through the quarter-wave plate layer 309 and is emitted without being absorbed by the guest-host liquid crystal layer 304. Therefore, a white display is obtained.
[0004]
[Problems to be solved by the invention]
Since the reflective display device uses an external light as it is without using a light source to display an image, it consumes less power and is expected as a display for a portable information terminal. The reflective display device displays an image by controlling external light incident on the liquid crystal panel with a liquid crystal layer. In the reflective display device, besides the liquid crystal serving as the electro-optic layer, another basic technique is a reflector. That is, the reflection type display device needs a reflection plate to reflect outside light. However, in the conventional example as shown in FIG. 7, the specular reflector (light reflecting layer 308) is used, so that the observer can observe the image only in the regular reflection direction of the illumination light source. In the regular reflection direction of the light source, the amount of illumination light is too strong, creating a feeling of illusion and conversely making observation difficult. In order to improve this, various diffuse reflection systems have been proposed. For example, a scattering film is attached to the front substrate so as to face the specular reflector formed on the rear substrate. The scattering film is obtained by dispersing fine transparent particles having different refractive indexes in a transparent resin substrate. The light reflected from the liquid crystal panel is diffused at a wide angle through the scattering film. Therefore, even if a point light source is used, the observer can observe the display image from a wide angle. As another method, there is a structure in which a diffuse reflection plate is mounted on the rear substrate instead of the specular reflection plate. This diffuse reflection plate has a concavo-convex structure on its surface, and light incident on the liquid crystal panel hits the concavo-convex reflection surface with various tilt angles and is reflected in various directions. Thereby, an angle sufficient for observation can be provided. Further, there is a structure in which a hologram reflector is attached to the rear substrate and a hologram scattering plate is attached to the front substrate. The hologram scattering plate can change the emission angle of light over a wide range by diffraction.
[0005]
However, any of the above-described diffuse reflection systems has a structure in which incident light is evenly diffused in all directions. In general, a reflective display device absorbs light with a dichroic dye contained in a liquid crystal layer or a polarizing plate disposed on a front substrate, and further with a color filter. The screen tends to be dark because the percentage of reflected light is very small. In addition to this, when the diffuse reflection method is adopted as described above, the incident light is diffused in all directions, so that the light reflected toward the observer is dramatically reduced. For this reason, it is not possible to obtain a display having a brightness that can withstand practical use. The present invention aims to improve the inefficient conventional diffuse reflection structure described above.
[0006]
[Means for solving the problems]
In order to solve the above-described problems of the prior art and achieve the object of the present invention, the following measures were taken .
[0007]
That is, the present invention includes a substrate in which a vertical direction and a horizontal direction orthogonal to the vertical direction are defined in advance, a set of convex portions arranged on the substrate and having inclined surfaces, and a light reflecting film covering the inclined surface. The area of the inclined surface of the convex portion inclined along the upward direction and the inclined surface of the convex portion inclined along the downward direction is equal to the inclined surface of the convex portion inclined along the left direction and the right side. It is a manufacturing method of a diffuse reflector larger than the area which combined the inclined surface of this convex part inclined along the direction, Comprising: It manufactures by the following processes. First, in a first step, a first resin film is formed on a substrate in accordance with a stripe pattern that is arranged at predetermined intervals in the vertical direction and extends in the horizontal direction. In the second step, a second resin film is formed on the substrate in accordance with the dot pattern arranged so as to overlap the step of the stripe pattern. In the third step, the substrate is heated to thermally deform the second resin film, and processed into a convex portion having an inclined surface related to the step. Finally, in the fourth step, a light reflecting film is formed by depositing a metal on the second resin film. Preferably, in the second step, the second resin film is formed in accordance with a dot pattern having a center point biased upward from below with respect to the center line of the stripe pattern.
[0008]
The present invention includes a reflective display device using the above-described diffuse reflector. That is, the reflection type display device according to the present invention basically includes a front substrate disposed on the incident side, a rear substrate bonded to the front substrate via a predetermined gap, and disposed on the reflection side. An electro-optical layer located on the front substrate side in the gap, a diffuse reflection layer located on the rear substrate side in the gap, and formed on at least one of the front substrate side and the rear substrate side. And an electrode for applying a voltage, and displays a screen that expands in the vertical and horizontal directions. The diffuse reflection layer includes a set of convex portions arranged on the rear substrate and individually having an inclined surface, and a light reflecting film covering the inclined surface. As a feature, each convex part has an inclined surface inclined along the left direction and an inclined surface inclined along the left direction and an inclined surface inclined along the left direction. was rather greater than the total area of the inclined surface, the diffuse reflection layer, a first step of forming a first resin film to the rear substrate in accordance with the stripe pattern extending in the left-right direction are arranged at predetermined intervals in the vertical direction, A second step of forming a second resin film on the rear substrate in accordance with the dot pattern arranged so as to overlap the step of the stripe pattern; and heating the rear substrate to thermally deform the second resin film to form the step It is manufactured by a third step of processing into a convex portion having such an inclined surface and a fourth step of depositing a metal from the second resin film to form a light reflection film . Preferably, in the diffuse reflection layer, the area of the inclined surface of the convex portion inclined along the upward direction is larger than the area of the inclined surface of the convex portion inclined along the downward direction .
[0009]
In the diffusive reflector according to the present invention, the area of the inclined surface positioned in the vertical direction is larger than the area of the inclined surface positioned in the horizontal direction. In general, when a reflective display device is used indoors, an illumination light source is disposed above and an observer is positioned below. The illumination light from above is diffused back and forth and reaches the observer located in the down direction. Therefore, sufficient light is reflected in a wide viewing angle range. On the other hand, in the indoor environment, it is not necessary to diffuse much in the left-right direction. Therefore, the area of the inclined surface in the left-right direction is reduced. In this way, by giving the diffusion plate anisotropy in the vertical direction and the horizontal direction, the light use efficiency from the illumination light source to the observer is remarkably improved.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a process diagram showing a method for manufacturing a diffuse reflector according to the present invention. This diffusive reflecting plate includes a substrate in which a vertical direction and a horizontal direction perpendicular thereto are defined in advance, a set of convex portions arranged on the substrate and having inclined surfaces, and a light reflecting film covering the inclined surface. Become. In order to manufacture a diffusive reflector having such a structure, first, in step (A), a first resin film is formed on a substrate 1 made of glass or the like in accordance with a stripe pattern arranged in the vertical direction at a predetermined interval and extending in the horizontal direction. 2 is formed. In the figure, a planar shape and a cross-sectional shape obtained by cutting out only one pixel are shown. As a specific forming method, for example, a photoresist is formed on the substrate 1 with a thickness of 1 μm or less. Next, after exposing the photoresist (first resin film 2) through a mask having a stripe pattern, the photoresist is patterned in a stripe shape by development. That is, in this embodiment, the first resin film 2 is patterned in a stripe shape using photolithography. One stripe width is, for example, about several μm. The present invention is not limited to photolithography. For example, the first resin film 2 can be formed in a stripe pattern by a screen printing method. Next, the process proceeds to step (B), and the second resin film 3 is formed on the substrate 1 in accordance with the dot pattern arranged so as to overlap the step 4 of the stripe pattern. In this embodiment, the dot patterns have an almost elliptical shape and are arranged in a lattice pattern. The important point is that the second resin film 3 is formed on the first resin film 2 so that the dot pattern is applied to the step 4 of the stripe pattern. The second resin film 3 can also be formed by photolithography using a photoresist. Screen printing may be applied instead of photolithography. Preferably, the second resin film 3 is formed in accordance with a dot pattern having a center point that is biased upward from below with respect to the center line of the stripe pattern. That is, the dot pattern of the second resin film 3 is not arranged so as to overlap the center of the stripe pattern of the first resin film 2, but from the lower side to the upper side of the substrate 1 (from the right to the left in the drawing). It is offset. Next, in step (C), the substrate 1 is heated to thermally deform the second resin film 3, and processed into a convex portion 6 having an inclined surface over the step 4. The first resin film 2 and the second resin film 3 that overlap each other are heated at a melting point or a softening point or higher to perform so-called reflow to form a convex portion 6 having a smooth inclined surface in the vertical direction. The individual convex portions 6 correspond to almost individual dot patterns. Finally, a light reflecting film 5 is formed by depositing a metal such as aluminum on the second resin film 3 by sputtering or vacuum deposition. Through the above steps, it is possible to manufacture a diffuse reflector that has an area of the inclined surface positioned in the vertical direction larger than that of the inclined surface positioned in the horizontal direction.
[0011]
FIG. 2 is a plan view (A) showing a finished product state of the diffuse reflector produced by the manufacturing method shown in FIG. As shown to (A), the board | substrate with which the up-down direction and the left-right direction orthogonal to this were prescribed | regulated previously was used for the diffuse reflection board. A set of convex portions 6 is arranged on the substrate 1 in a lattice pattern. Each convex part 6 has an inclined surface in the vertical and horizontal directions. As a characteristic matter, the area of the inclined surface positioned in the vertical direction is larger than the area of the inclined surface positioned in the horizontal direction. That is, the second resin film 3 that substantially constitutes the convex portion 6 has a dot shape, and a part of the second resin film 3 hangs on the step 4 of the stripe-shaped first resin film 2. For this reason, the inclined surface of the convex part 6 has a large inclined surface along the up-down direction of the level | step difference 4 extended in the left-right direction.
[0012]
As shown in (B), the area of the upper part is larger than the area of the lower part among the inclined surfaces located in the vertical direction. That is, the convex portion 6 does not become symmetric when cut along the vertical direction, and the inclined area of the upper portion is equivalent to the amount that the dot-like second resin film 3 is biased upward from the stripe-like first resin film 2. It is larger than the inclined area of the lower part. When such a diffuse reflector is incorporated in a display device, the illumination light source 70 is generally positioned upward in the screen and the observer 50 is positioned downward in an indoor environment. In this case, the illumination light from the upper direction is scattered up and down, and sufficient light is reflected in a wide viewing angle range to reach the observer 50 positioned in the lower direction. On the other hand, in the left-right direction (direction perpendicular to the paper surface), the area of the inclined surface is reduced because it is not necessary to diffuse only when the display device is used in an indoor environment. In this way, by making the area of the inclined surface of the fine convex portion formed on the diffusive reflecting plate anisotropic in the vertical direction and the horizontal direction, the illumination light can be efficiently used.
[0013]
FIG. 3A is a plan view of a conventional diffuse reflector, and FIG. As shown to (A), the conventional diffuse reflector has the structure where the hemispherical convex part 6 was fundamentally arranged in the grid | lattice form. Each convex part 6 is obtained by reflowing the resin film 3 patterned in a circular shape. The hemispherical convex portion 6 has substantially the same inclined area in the vertical and horizontal directions. That is, in the conventional diffuse reflector, the reflecting surface is uniformly distributed with respect to the azimuth angle and the polar angle. When completely diffused light is incident on such a spherical surface, the reflected light in the front direction becomes stronger. However, under a point light source, light incident on the diffuse reflector is reflected uniformly in all directions, and very little direct observation light contributes to the brightness of the reflective display device. Such a diffuse reflector is not suitable for a reflective display device used in an indoor environment.
[0014]
FIG. 4 is a schematic partial cross-sectional view showing an example of a reflective display device incorporating the diffuse reflector according to the present invention. This display device is configured using a pair of front and rear substrates 101 and 102 bonded to each other through a predetermined gap. The front substrate 101 is located on the incident side and is made of a transparent base material such as glass. On the other hand, the rear substrate 102 is located on the reflection side, and it is not always necessary to use a transparent material. A guest-host liquid crystal layer 103 is held as an electro-optical layer in the gap between the pair of substrates 101 and 102. This guest-host liquid crystal layer 103 is mainly composed of nematic liquid crystal molecules 104 having negative dielectric anisotropy, and contains a dichroic dye 105 at a predetermined ratio. A counter electrode 106 and an alignment layer 107 are sequentially formed on the inner surface of the front substrate 101. The counter electrode 106 is made of a transparent conductive film such as ITO. The alignment layer 107 is made of, for example, a polyimide film, and the guest-host liquid crystal layer 103 is vertically aligned. The guest-host liquid crystal layer 103 is maintained in a vertical alignment when no voltage is applied, and shifts to a horizontal alignment when a voltage is applied.
[0015]
On the rear substrate 102, at least a switching element made of a thin film transistor 108, a diffuse reflection layer 109, a quarter-wave plate layer 110, and a pixel electrode 111 are formed. The quarter-wave plate layer 110 is formed on the thin film transistor 108 and the diffuse reflection layer 109, and a contact hole 112 communicating with the thin film transistor 108 is provided. The pixel electrode 111 is patterned on the quarter-wave plate layer 110. Accordingly, a sufficient electric field can be applied to the guest-host liquid crystal layer 103 between the pixel electrode 111 and the counter electrode 106. The pixel electrode 111 is electrically connected to the thin film transistor 108 through a contact hole 112 opened in the quarter-wave plate layer 110.
[0016]
Hereinafter, specific explanations will be given for each element. In this example, the quarter-wave plate layer 110 is composed of a uniaxially oriented polymer liquid crystal film. A base alignment layer 113 is used to uniaxially align the polymer liquid crystal film. A planarization layer 114 is interposed to fill the unevenness of the thin film transistor 108 and the diffuse reflection layer 109, and the above-described base alignment layer 113 is formed on the planarization layer 114. A quarter-wave plate layer 110 is also formed on the surface of the planarizing layer 114. In this case, the pixel electrode 111 is connected to the thin film transistor 108 through a contact hole 112 provided through the quarter-wave plate layer 110 and the planarization layer 114. The diffuse reflection layer 109 is subdivided corresponding to each pixel electrode 111. The individual subdivided portions are connected to the same potential as the corresponding pixel electrode 111. With such a configuration, an unnecessary electric field is not applied to the quarter-wave plate layer 110 or the planarization layer 114 interposed between the diffuse reflection layer 109 and the pixel electrode 111. The diffuse reflection layer 109 includes a convex portion 109a according to the present invention, and the surface thereof is covered with a light reflection film 109b. As described above, the inclined surface of each protrusion 109a has a desired anisotropy in the vertical and horizontal directions. The diffuse reflection layer 109 includes an uneven reflection surface having anisotropy, and prevents mirror reflection of incident light to improve image quality. An alignment layer 115 is formed so as to cover the surface of the pixel electrode 111 and is in contact with the guest-host liquid crystal layer 103 to control the alignment. In this example, this alignment layer 115 is aligned with the opposing alignment layer 107 to vertically align the guest-host liquid crystal layer 103. Finally, the thin film transistor 108 has a bottom gate structure, and has a stacked structure in which a gate electrode 116, a gate insulating film 117, and a semiconductor thin film 118 are stacked in order from the bottom. The semiconductor thin film 118 is made of, for example, polycrystalline silicon, and the channel region aligned with the gate electrode 116 is protected from the front side by a stopper 119. The bottom-gate thin film transistor 108 having such a structure is covered with an interlayer insulating film 120. A pair of contact holes are opened in the interlayer insulating film 120, and the source electrode 121 and the drain electrode 122 are electrically connected to the thin film transistor 108 through these contact holes. These electrodes 121 and 122 are formed by patterning, for example, aluminum. The drain electrode 122 is at the same potential as the diffuse reflection layer 109. The pixel electrode 111 is electrically connected to the drain electrode 122 through the contact hole 112 described above. On the other hand, a signal voltage is supplied to the source electrode 121.
[0017]
FIG. 5 is a schematic view showing another example of the reflection type display device using the diffuse reflection plate according to the present invention. This example is a reflective display device using a single polarizer. As shown in the figure, this reflection type display device has a polarizer 204, a compensation retardation film 200, a liquid crystal 230 as an electro-optic layer, and a diffuse reflection plate 208 stacked in order from the front. A transmission axis of the polarizer 204 is indicated by 204a. The absorption axis is perpendicular to the transmission axis 204a. The compensation retardation film 200 is made of a uniaxial birefringent material, and its optical axis is represented by 200a. The liquid crystal 230 can employ a TN (twisted nematic) mode, an STN (super twisted nematic) mode, an OCB (optically compensated bend) mode, or the like. Incident light is converted into linearly polarized light by the polarizer 204. The liquid crystal 230 functions as a quarter-wave plate and converts linearly polarized light into circularly polarized light. The circularly polarized light is reflected by the diffuse reflector 208 and then passes through the liquid crystal 230 again. As a result, circularly polarized light becomes linearly polarized light. However, the vibration direction of the reflected linearly polarized light is rotated by 90 degrees with respect to the incident linearly polarized light. Therefore, the outgoing linearly polarized light is absorbed by the polarizer 204. Therefore, a black display can be obtained. When a voltage is applied to the liquid crystal 230 and the function as a quarter-wave plate is lost, the incident linearly polarized light is reflected by the diffuse reflector 208 without changing the vibration direction and passes through the polarizer 204. Thereby, white display is obtained. The diffuse reflection plate 208 is composed of a set of convex portions each having an inclined surface and a light reflecting film covering the inclined surface according to the present invention. The area of the inclined surface located in the up-down direction of each convex portion is set larger than the area of the inclined surface located in the left-right direction.
[0018]
FIG. 6 shows another example of the reflection type display device using the diffuse reflection layer according to the present invention. The diffuse reflection layer according to the present invention is formed inside the panel. This embodiment is a Heilmeier type guest-host liquid crystal display device, in which (A) represents a voltage non-application state and (B) represents a voltage application state. This reflective display device uses a p-type dye and nematic liquid crystal (Np liquid crystal) having a positive dielectric anisotropy. The p-type dichroic dye has an absorption axis substantially parallel to the molecular axis, strongly absorbs the polarization component Lx parallel to the molecular axis, and hardly absorbs the polarization component Ly perpendicular thereto. In the voltage-less application state shown in (A), the polarization component Lx contained in the incident light is strongly absorbed by the p-type dye, and the display device is colored. On the other hand, in the voltage application state shown in (B), the Np liquid crystal having positive dielectric anisotropy rises in response to the electric field, and the p-type dye is aligned in the vertical direction accordingly. For this reason, the polarization component Lx is only slightly absorbed and reflected by the diffuse reflection layer, and the display device exhibits almost white color. The other polarization component Ly contained in the incident light is hardly absorbed by the dichroic dye in either the voltage application state or the voltage non-application state. Therefore, in the Heilmeier type guest-host liquid crystal display device, one polarizing plate is interposed in advance, and the other polarization component Ly is removed to improve the contrast.
[0019]
【The invention's effect】
As described above, according to the present invention, in the diffuse reflector, the area of the reflective inclined surface positioned in the vertical direction of the screen is larger than the area of the reflective inclined surface positioned in the horizontal direction of the screen. By using the diffuse reflection plate having such a configuration, it becomes possible to efficiently emit illumination light outside the panel, and a reflective display device that is brighter and easier to observe than the conventional diffuse reflection plate can be realized.
[Brief description of the drawings]
FIG. 1 is a process diagram showing a method of manufacturing a diffuse reflector according to the present invention.
FIG. 2 is an explanatory diagram showing the shape and usage of the diffuse reflector according to the present invention.
FIG. 3 is an explanatory view showing the shape and usage of a conventional diffuse reflector.
FIG. 4 is a partial cross-sectional view showing an example of a display device incorporating the diffuse reflector according to the present invention.
FIG. 5 is a schematic view showing another example of a display device using the diffuse reflector according to the present invention.
FIG. 6 is a schematic view showing another example of a display device incorporating a diffuse reflector according to the present invention.
FIG. 7 is a cross-sectional view showing an example of a conventional reflective display device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 2 ... 1st resin film, 3 ... 2nd resin film, 4 ... Level difference, 5 ... Light reflection film, 6 ... Convex part

Claims (4)

It consists of a substrate in which a vertical direction and a horizontal direction orthogonal thereto are defined in advance, a set of convex portions arranged on the substrate and having inclined surfaces individually, and a light reflecting film covering the inclined surface , The area of the inclined surface of the convex portion inclined along with the inclined surface of the convex portion inclined along the downward direction is inclined along the inclined surface of the convex portion inclined along the left direction and the right direction. And a method of manufacturing a diffuse reflector larger than the combined area of the inclined surfaces of the convex portions ,
A first step of forming a first resin film on the substrate in accordance with a stripe pattern arranged in the vertical direction at a predetermined interval and extending in the horizontal direction;
A second step of forming a second resin film on the substrate in accordance with the dot pattern arranged so as to overlap the step of the stripe pattern;
A third step of heating the substrate and thermally deforming the second resin film to form a convex portion having an inclined surface over the step;
And a fourth step of depositing a metal from the second resin film to form a light reflection film.   4. The diffuse reflection according to claim 3, wherein in the second step, the second resin film is formed in accordance with a dot pattern having a center point that is biased upward from below with respect to the center line of the stripe pattern. A manufacturing method of a board. A front substrate disposed on the incident side, a rear substrate bonded to the front substrate via a predetermined gap and disposed on the reflection side, an electro-optic layer located on the front substrate side in the gap, and in the gap A reflection reflecting layer that has a diffuse reflection layer located on the rear substrate side and an electrode that is formed on at least one of the front substrate side and the rear substrate side and applies a voltage to the electro-optic layer, and that spreads in the vertical and horizontal directions. Type display device,
The diffuse reflection layer is composed of a set of convex portions arranged on the rear substrate and individually having an inclined surface, and a light reflecting film covering the inclined surface,
Each convex part is composed of an inclined surface inclined along the left direction and an inclined surface inclined along the right direction. larger than the combined area rather than,
A first step of forming the first resin film on the rear substrate in accordance with a stripe pattern arranged in the vertical direction at a predetermined interval and extending in the horizontal direction;
A second step of forming a second resin film on the rear substrate in accordance with the dot pattern arranged so as to overlap the step of the stripe pattern;
A third step of heating the rear substrate to thermally deform the second resin film and processing into a convex portion having an inclined surface over the step;
A reflective display device manufactured by the fourth step of depositing a metal from the second resin film to form a light reflecting film . 4. The reflection according to claim 3, wherein the diffuse reflection layer has an area of the inclined surface of the convex portion inclined along the upward direction larger than an area of the inclined surface of the convex portion inclined along the downward direction. Type display device.

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