JP2001337322A - Reflection plate for reflection type liquid crystal display device, and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily obtain a form of reflection plate with good controlling property such that the reflected light concentrated in a specified angle direction can be obtained in a reflection type liquid crystal display device. SOLUTION: The reflection plate is manufactured by forming a step-like layer having a cross section with a plurality of trapezoids or rectangles stacked one another on a substrate and coating the surface of the step-like layer with a reflection layer consisting of a reflective material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a reflection plate of a reflection type liquid crystal display device and a method of manufacturing the same. The present invention also relates to a reflection type liquid crystal display device mounted on a portable device such as a mobile phone, a portable information terminal, and an electronic organizer.

[0002]

2. Description of the Related Art A reflection type liquid crystal display device is mounted as a display device such as a portable information terminal or a portable telephone which requires a low power consumption and a bright image display.

[0003] The problem of the reflection type liquid crystal display device so far is that the original image is difficult to see due to unintended reflection components such as specular reflection from the surface of the liquid crystal display device in the viewing direction.
There was a point that the displayed image was dark. As a method of improving the former problem, a method of creating random irregularities on the surface of the reflector and distributing the reflection direction of incident light at a wide angle is known, but this method improves the latter problem. Was known to be difficult. It is known that as a method of improving the latter problem, a reflector having an asymmetric shape may be formed.

FIG. 14 is a view showing the shape of a conventional reflector disclosed in Japanese Patent Application Laid-Open No. 9-80426. FIG. 14B shows the surface of the panel.
(A) shows a cross section. In FIG. 14, 101
Is a reflection plate, 101a is a convex portion, 102 is a substrate, α is the inclination angle of the projection inclined surface which is on the upper side of the panel in use, and β is the inclination angle of the projection inclined surface which is on the lower side of the panel in use.

[0005] As shown in FIG.
A large number of fan-shaped convex portions 101a are formed on the surface of the surface 01. As shown in FIG. 14 (a), the apex of the convex portion 101a is unevenly distributed below the panel in use and the upper and lower sides are inclined. In use, the inclination angle α of the inclined surface on the upper side of the panel is smaller than the inclination angle β of the inclined surface on the lower side of the panel, and the inclined surface on the upper side of the panel is more gradually inclined than the inclined surface on the lower side of the panel. ing.

[0006] Japanese Patent Application Laid-Open No. 9-80426 discloses that
A stripe-shaped convex portion 101 having a cross section shown in FIG.
There is also disclosed a reflector in which a is formed so as to extend parallel to the left and right of the panel in use.

With these reflectors, the direction of reflected light can be concentrated in a specific direction, and a reflection type liquid crystal display device capable of displaying a bright image can be manufactured.

[0008] A method of manufacturing these reflectors will be described with reference to FIG. FIG. 15 is a diagram showing a conventional method for manufacturing a reflector, disclosed in Japanese Patent Application Laid-Open No. 10-177106. In FIG. 15, reference numeral 115 denotes a reflection plate,
Reference numeral 11 denotes a glass substrate, 112 denotes a resist film, 112a denotes a projection, 113 denotes a photomask, 114 denotes a metal thin film, and Q denotes light exposure.

In FIG. 15A, a resist film 112 is formed on a glass substrate 111. Next, as shown in FIG. 15B, a photomask 113 was set, and exposure and development were performed to obtain a striped resist film 112 shown in FIG. 15C. After that, as shown in FIG. 15D, the glass substrate 111 is tilted and heat treatment is performed. By the heat treatment, an asymmetric convex portion 112a having a smooth and biased distribution of the inclination angle is obtained as shown in FIG. In FIG. 15F, a metal thin film 114 was formed on the surface to form a reflector 115.

By using this method, it is possible to relatively easily produce a reflector having an asymmetrical inclination angle distribution.

[0011]

However, in the above-described conventional method of manufacturing a reflector, an arbitrary tilt angle is obtained by applying a resist film and then tilting the film to cause the film to flow. In addition, there is a problem that it is difficult to control the shape, and an optimum reflector shape cannot be obtained.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a reflection plate having a desired shape is provided.
It is an object to obtain the shape easily and with good controllability.

[0013]

The reflection plate of the reflection type liquid crystal device according to the present invention has a cross section of the reflection plate formed of a plurality of stepped layers in which a plurality of trapezoidal or rectangular shapes overlap, and a reflective material is provided on the stepped layer. A reflective layer comprising:

Further, the present invention is characterized in that the step layer has a two-step or three-step shape.

Further, a part or all of the step layer is formed of a metal material and is electrically connected to the pixel electrode.

Further, the present invention is characterized in that the reflection layer itself is an electrode for applying a voltage to the liquid crystal.

A flattening layer is formed on the reflective layer, and an electrode for applying a voltage to the liquid crystal is provided on the flattening layer.

Further, a smoothing layer is formed on the stepped layer to smooth the surface shape.

Further, the smoothing layer is formed by uniformly applying the smoothing layer, followed by baking at a high temperature in an inclined state and solidifying it.

Further, the smoothing layer is formed by uniformly applying the smoothing layer, removing a part of the smoothing layer using photolithography, and then baking at a high temperature to solidify. It is characterized by the following.

Further, a part or all of each layer of the staircase layer constituting the staircase layer is formed simultaneously with the signal wiring or the switching element.

Further, when a part of the material of the stepped layer is made of a metal material, the stepped layer is electrically connected to the pixel electrode.

Further, a reflection type liquid crystal display device using a reflection plate having a stepped layer is mounted on a portable device.

[0024]

Embodiment 1 FIG. 1 is a cross-sectional view for explaining a shape of a reflector according to Embodiment 1 of the present invention. In the case where the liquid crystal panel is actually visually recognized by being incorporated in the liquid crystal panel, the left side of FIG.

In FIG. 1, a stepped layer 12 is formed on a glass substrate 20, and a stepped portion is formed by covering the surface of the stepped layer 12 with a reflective layer 11. The left side of the step portion has a stepped shape including a plurality of slopes and a plurality of flat portions, and the right side of the step portion has a steep slope having no flat portion.

When light is incident on the reflector having such a shape from the upper left direction in FIG. 1, no light is incident on the steep slope portion on the right side of the step portion, and the flat portion having the step shape on the left side of the step portion is not formed. Light enters the slope and is reflected by the reflective layer 11. At this time, the reflection direction of the light incident on the flat portion is almost equal to the direction of the reflected light reflected on the liquid crystal panel surface,
The light incident on the slope is reflected in a different direction from the light reflected from the liquid crystal panel surface. Therefore, the direction of the reflected light reflected by the step portion is different from the direction of the reflected light from the liquid crystal panel surface as a whole, and thus the visibility is improved.

That is, by providing the reflecting plate with the stepped portion as shown in FIG. 1, light can be reflected in a specific direction different from the direction of the reflected light from the liquid crystal panel surface. Since the step portion has a shape in which a plurality of rectangles or trapezoids having substantially uniform thickness and no gentle slope are stacked, they can be easily formed by a so-called thin film process technique.

FIG. 2 shows a specific target value of the inclination angle.
This will be described with reference to FIG. FIG. 2A is a diagram schematically illustrating a cross section of the liquid crystal panel, and FIG. 2B is an enlarged view of a portion X thereof.

As shown in FIG. 2, when the direction R of the incident light 60 is 30 °, in order to direct the reflected light B61 in the direction of 0 ° which is the front of the liquid crystal panel, a polarizing plate and a retardation plate 54 are required. When the refractive index of the front glass substrate 53 and the refractive index of the liquid crystal layer 52 are all approximated to be 1.52 and isotropic and calculated using Snell's law, the optimum value of the inclination angle γ of the asymmetric reflection surface 51 is 10 °. Becomes

At this time, the reflected light A from the liquid crystal panel surface
Since the direction of 62 and the direction of the reflected light B61 from the asymmetric reflection surface 51 are different, the visibility is improved. If the inclination angle can have an arbitrary width distribution, the viewing direction can also have an arbitrary allowable width. Therefore, it is desirable that the inclination angle has a certain degree of angle distribution centering on 10 degrees. If the asymmetric reflection surface 51 has a symmetric shape, the opposite side becomes an invalid reflection surface, which is not desirable. Therefore, an asymmetric shape in which the opposite side has a vertically steep triangular shape is desirable.

As shown in FIG. 2C, the asymmetrical reflection surface 51 is formed in a step shape, and the inclination angle γ is 1 on average.
In order to make it 0 °, the pitch P and the height D of each step forming the step shape are set to, for example, when the pitch P is 5 μm, the height is set to 0.88 μm, and the pitch P is set to 10
In the case of μm, the height D may be set to 1.76 μm. However, if the pitch P is too small or too large, it is difficult to form the film by a thin film process. Therefore, the pitch P is preferably about 5 to 15 μm.

Embodiment 2 FIG. 3 is a cross-sectional view for explaining a shape of a reflector according to Embodiment 2 of the present invention.

In FIG. 3, reference numeral 13 denotes a smoothing layer used to make the unevenness of the step layer 12 smooth.
By providing the smoothing layer 13, the surface shape of the reflective layer 11 is smaller in unevenness and smoother than in the first embodiment. Therefore, the distribution of the inclination angle of the reflection layer 11 is concentrated near the target angle, and the visibility is improved because the intensity distribution of the reflected light is concentrated in the viewing direction.

Third Embodiment FIG. 4 is a diagram for explaining a method of forming a smoothing layer according to a third embodiment of the present invention. In order to simplify the description, the staircase layer 12 has a two-layer structure including a first staircase layer 12a and a second staircase layer 12b.

First, the first layer 1 of the staircase layer is formed on the glass substrate 20.
2a and the staircase layer second layer 12b (FIG. 4)
(A)).

Next, a smoothing layer 13 is applied uniformly on the step layer 12. When the liquid smoothing layer 13 is applied by a spin coating method or the like, the solution accumulates at the bottom of the stepped layer, and almost no film adheres to the upper part of the stepped layer (FIG. 4B).

Thereafter, the whole is inclined and fired at a high temperature (FIG. 4 (c)), so that the smoothing layer 13 is solidified while flowing to the right side of the figure, and an inclined surface having a smooth angular distribution is formed. it can. (FIG. 4D).

Here, specific examples of each constituent material will be described. The pitch between adjacent step layers 12 is 5 μm, and the first step layer 12 a is formed by dry etching using SiN to have a thickness of 0.4 μm and a width of 3.0 μm. The stepped layer second layer 12b is formed by wet etching using Cr and has a thickness of 0.4 μm and a width of 1.0 μm.
The smoothing layer 13 is made of a photoresist (for example, T
FR-B) was applied to a thickness of 0.3 μm, and the temperature was 200 ° C.
High-temperature baking is performed at an inclination angle of 30 degrees for 1 hour. This makes it possible to obtain an inclined surface having an average inclination angle of about 10 °. As for the range of the thickness of the smoothing layer 13,
If it is equal to or greater than the thickness of each step layer, the whole will be averaged and the direction of reflected light will be concentrated too much, and if it is too thin than each layer of the step layer, it will be clear that the effect of smoothing will not be obtained, For example, in the case of the above example, 0.2 to
The range of 0.6 μm is a guide.

The materials are not limited to those described here. For example, SiO ₂ or Al may be used for each layer of the step layer, and a resin film having no photosensitivity may be used for the smoothing layer 13. It is possible to use. Also, the pitch between adjacent step phases and the width of each step layer need not be formed as described herein.

Fourth Embodiment FIG. 5 is a diagram for explaining a method of forming a smoothing layer according to a fourth embodiment of the present invention. In order to simplify the description, the staircase layer 12 has a two-layer structure including a first staircase layer 12a and a second staircase layer 12b.

First, the first layer 1 of the staircase layer is formed on the glass substrate 20.
2a and the second step layer 12b are formed (FIG. 5).
(A)).

Next, a smoothing layer 13 is applied uniformly on the step layer 12. When the liquid smoothing layer 13 is applied by a spin coating method or the like, the solution accumulates at the bottom of the step layer, and almost no film adheres to the top of the step layer (FIG. 5B).

After that, a part of the smoothing layer 13 is selectively removed. Specifically, after the smoothing layer 13 is applied, preliminary drying is performed, and the solution accumulated at the bottom of the step portion is selectively removed by photolithography (FIG. 5C).

Subsequently, high-temperature baking is performed to complete the formation of the smoothing layer 13. Immediately after the photoengraving process, the shape is slightly sharp, but an inclined surface having a smooth angular distribution can be formed by slightly changing the shape by high-temperature baking (FIG. 5D).

Here, specific examples of each constituent material will be described. The pitch between adjacent step layers 12 is 5 μm, and the first step layer 12 a is formed by dry etching using SiN to have a thickness of 0.4 μm and a width of 3.0 μm. The stepped layer second layer 12b is formed by wet etching using Cr and has a thickness of 0.4 μm and a width of 1.0 μm.
The smoothing layer 13 is made of a photosensitive acrylic film (for example, JSR
PC-335) is applied to a thickness of 0.3 μm and the width is 1.0 μm.
m is removed by exposure and development. Thereafter, high-temperature baking is performed at 220 ° C. for 1 hour. At this time, high-temperature firing may be performed while being inclined as described in the third embodiment. This makes it possible to obtain an inclined surface having an average inclination angle of about 10 °. As for the range of the thickness of the smoothing layer, as in the case of the third embodiment, for example, in the case of the above example, the range of 0.2 to 0.6 μm is a standard.

The materials are not limited to those described above. For example, SiO ₂ or Al may be used for the step layer, and a resin film having no photosensitivity may be used for the smoothing layer. A method of masking and etching using a photoresist may be used. Also, the pitch between adjacent step phases and the width of each step layer need not be formed as described herein.

Embodiment 5 FIG. 6 is a cross-sectional view for explaining the shape of a reflector according to Embodiment 5 of the present invention.

In FIG. 6, reference numeral 12a denotes a first step layer,
Reference numeral 12b denotes a second step layer. By forming the staircase layer 12 in a two-layer configuration, it is possible to easily form the shape. Further, as shown in FIG. 6B, by providing the smoothing layer 13 and performing smoothing, it becomes easy to produce a shape in which the distribution of the inclination angles is concentrated at the target angle.

Further, it is not necessary that two step layers are present continuously. As shown in FIG. 6C, the same effect can be obtained even when the stepped layer second layer 12b is present on the stepped layer first layer 12a via the intermediate layer 14.

Further, as shown in FIG.
After forming the staircase protection layer 15 on the smoothing layer 1
The same effect can be obtained by forming the reflective layer 3 and the reflective layer 11. In such a configuration, there is a case where at least a part of the staircase layer 12 and the reflective layer 11 are each made of a conductive material, and it is necessary to secure electrical insulation between the two.

Sixth Embodiment FIG. 7 is a view for explaining a shape of a reflector according to a sixth embodiment of the present invention.

In FIG. 7, reference numeral 12a denotes a first step layer,
Reference numeral 12b denotes a stepped layer second layer, and 12c denotes a stepped layer third layer. As shown in FIG. 7A, by forming the staircase layer 12 in a three-layer configuration, the shape can be easily manufactured.

Further, as shown in FIG. 7B, by providing the smoothing layer 13 and performing smoothing as in the fifth embodiment, the shape in which the distribution of the inclination angles is concentrated at the target angle is obtained. It is easy to manufacture. Further, similarly to FIG. 6C in the fifth embodiment, the step layer 12 does not need to be continuous, and an intermediate layer may exist between the step layers. Further, as in FIG. 6D in the fifth embodiment, the staircase layer 1
After forming the staircase protection layer 15 on the smoothing layer 1
3 and the reflective layer 11 may be formed.

Seventh Embodiment FIGS. 8 and 9 are views for explaining a method for simultaneously forming a TFT element for driving liquid crystal and a step layer according to a seventh embodiment of the present invention. FIG. 8 shows a II cross section of the reflector of FIG.

8 and 9, 20 is a glass substrate, 21 is a gate electrode, 22 is a gate insulating film, 23 is amorphous silicon, 24 is a source / drain electrode, 2
5 is a TFT protective film, and 26 is a reflective layer.

A process for manufacturing the reflection plate shown in FIG. 9 will be described with reference to FIG.

First, as shown in FIG. 8A, a gate electrode 21 is formed on a glass substrate 20. At this time, the step layer first layer 12a is also formed at the same time using the same material as the gate electrode 21.

Next, as shown in FIG. 8B, a gate insulating film 22 is formed on the entire surface. At this time, the entire surface of the step layer first layer 12a is covered with the gate insulating film 22.

Next, as shown in FIG. 8C, an amorphous silicon layer 23 is formed. Here, the amorphous silicon layer 23 is not related to the step layer.

Next, as shown in FIG.
A drain electrode 24 is formed. At this time, the staircase layer second layer 12b is also formed at the same time.

Next, as shown in FIG.
A protective layer 25 for ensuring element insulation is formed. At this time, the protective layer 25 is also formed on the stepped layer and plays a role as a smoothing layer in the stepped portion. Therefore, the protective layer 25
May be the same as the thickness and material of the smoothing layer. If sufficient insulating ability cannot be obtained with the same film thickness and material as the smoothing layer, first a thin film with high insulating ability is formed thinly over the entire surface, and then the smoothing layer is formed with an arbitrary shape and size. do it.

Finally, as shown in FIG. 8F, a reflection layer 26 is formed, and the reflection plate of FIG. 9 is completed.

By using the above steps, the TFT
Since a stepped layer can be formed at the same time as the formation of the element, a reflector having a stepped layer can be formed without increasing the number of steps.

In this embodiment, the steps are described by taking an example of an inverted staggered TFT element in which a gate electrode is present below. However, the present invention can be applied to other switching elements. It is also possible to produce a step layer at the same time as the production.

Eighth Embodiment FIG. 10 is a view for explaining a reflector according to an eighth embodiment of the present invention. This embodiment is characterized in that at least a part of the step layer is electrically connected to the pixel electrode.

The reflector of the present embodiment is manufactured by the same steps as in FIG. In FIG. 10, the components denoted by the same reference numerals as those in FIGS. 8 and 9 are the same or equivalent, and the description is omitted. FIG. 10B shows FIG.
FIG. 2A shows a cross section taken along the line II-II of FIG. 1A, but shows a state before the reflective layer 26 is formed for the sake of explanation.

As described in the seventh embodiment, FIG.
In the step shown in FIG. 4D, the source / drain electrodes 24 and the second step layer 12b are formed simultaneously. Therefore, in the present embodiment, the source / drain electrode 24 and the stepped second layer 1
2b was formed in an electrically connected state. With this configuration, it is possible to eliminate the occurrence of parasitic capacitance and to prevent adverse effects such as signal delay when driving the liquid crystal element.

Ninth Embodiment FIG. 11 is a view for explaining a reflector according to a ninth embodiment of the present invention. This embodiment is characterized by a structure in which a voltage is directly applied to the reflective layer.

In FIG. 11, the source / drain electrodes 24 of the TFT element and the reflective layer 26 are electrically connected via a contact hole provided in the TFT protective film 25, and the alignment film 32 and the liquid crystal The structure includes a layer 37, an alignment film 32, a transparent electrode 34, a color filter 35, a color filter side glass substrate 31, a retardation plate 38, and a polarizing plate 39. When the guest-host type is used for the liquid crystal layer 37, the retardation plate 38 and the polarizing plate 39 are not required.

When a voltage is applied to the liquid crystal, the reflection layer 26 and T
Since the source / drain electrodes 24 of the FT element are directly electrically connected, no voltage loss occurs, and the liquid crystal can be driven at a low voltage.

Tenth Embodiment FIG. 12 is a view for explaining a reflector according to a tenth embodiment of the present invention. The present embodiment is characterized in that a voltage is applied to the liquid crystal between the transparent electrodes by disposing a transparent electrode after flattening the reflective layer so that no voltage is directly applied to the reflective layer. .

In FIG. 12, the reflection layer 26, the planarizing film 3
Except for the sixth and transparent electrodes 34, the arrangement is the same as that of the ninth embodiment described with reference to FIG.

Consider a problem that occurs when the surface of the reflective layer 26 is not flattened. The thickness of the liquid crystal layer is generally about 4 μm, and the height difference of the reflection layer 26 is 1 μm.
Then, the layer thickness of the liquid crystal is the center value plus or minus 0.5 μm
With a distribution of Since the optical characteristics of the liquid crystal are clearly different between the thin part and the thick part of the liquid crystal layer even when the same voltage is applied,
A distribution occurs in brightness, for example, causing a decrease in contrast. To improve this, the transparent electrode 34 for applying a voltage may be formed after the surface of the reflective film 26 is flattened by the flattening layer 36 as shown in FIG. As a result, it is possible to obtain a reflector in which the optical adverse effect due to the unevenness of the reflection layer is eliminated.

Eleventh Embodiment FIG. 13 shows an eleventh embodiment of the present invention.
FIG. 7 is a diagram showing a state in which a reflection type liquid crystal display device using the above-mentioned reflection plate is mounted on a mobile phone.

In FIG. 13, reference numeral 41 denotes a portable telephone;
Is a numeric keypad, 43 is a function key, and 44 is a liquid crystal display. The liquid crystal display unit 44 includes the first and second embodiments of the present invention,
3, 4, 5, 6, 7, 8, 9, and 10,
A reflection type liquid crystal display device having a reflection plate having a stepped layer is used.

The reflector used here can obtain a bright image with low power consumption, and enables a mobile phone driven by a built-in battery to operate for a long time.

In addition to the portable telephone shown in the above-described example, a bright display with low power consumption can be obtained when the portable telephone is mounted on another portable device such as a portable information terminal.

[0078]

According to the present invention, since the cross section of the reflector is a stepped layer in which a plurality of trapezoidal or rectangular shapes overlap, a reflector capable of reflecting light in a specific direction can be manufactured very easily. be able to.

Further, according to the present invention, by forming a smoothing layer on the step layer to smooth the surface shape,
The distribution of the inclination angle of the reflective layer can be concentrated near the target angle, so that the reflected light intensity in the viewing direction is improved and the display quality is improved. Further, according to the present invention, since the smoothing layer is uniformly applied and then baked at a high temperature and solidified in an inclined state, a shape having an arbitrary inclination angle distribution can be easily produced. .

Further, according to the present invention, after the smoothing layer is uniformly applied, the smoothing layer is partially removed using photolithography and solidified by baking at a high temperature. According to the present invention, a staircase layer is formed simultaneously with a signal wiring or a switching element, so that the number of steps can be reduced, and any reflection characteristic can be obtained at low cost. It is possible to produce a reflecting plate having the same.

According to the present invention, when the stepped layer is made of a metal material, the stepped layer and the pixel electrode are electrically connected to each other. Signal delay and the like can be prevented.

According to the present invention, since the reflection plate is an electrode for directly applying a voltage to the liquid crystal, no voltage loss occurs and the liquid crystal can be driven at a low voltage.

Further, according to the present invention, the flattening layer is formed on the reflective layer, and the electrode for applying a voltage to the liquid crystal is formed on the flattening layer. It is possible to obtain a reflector having no adverse effects.

Further, according to the present invention, since a reflection type liquid crystal display device having a reflection plate having a stepped layer is mounted on a portable device, a bright image can be obtained with low power consumption, and a built-in battery can be used. Long-term operation is possible.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view for explaining a shape of a reflector according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating the relationship between the angle of inclination of a reflector and reflected light according to the present invention.

FIG. 3 is a cross-sectional view for explaining a reflector according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional view for describing a method for manufacturing a smoothing layer according to a third embodiment of the present invention.

FIG. 5 is a cross-sectional view for describing a method for manufacturing a smoothing layer according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view illustrating a reflector according to a fifth embodiment of the present invention.

FIG. 7 is a sectional view illustrating a reflector according to a sixth embodiment of the present invention.

FIG. 8 is a diagram illustrating a manufacturing method according to a seventh embodiment of the present invention for simultaneously forming each step layer and a TFT element.

FIG. 9 is a diagram for explaining a manufacturing method according to a seventh embodiment of the present invention for simultaneously forming each stepped layer and a TFT element.

FIG. 10 is a cross-sectional view illustrating a reflector according to an eighth embodiment of the present invention.

FIG. 11 is a cross-sectional view of an entire liquid crystal panel for explaining a reflector in which a voltage is directly applied to a reflection layer according to a ninth embodiment of the present invention.

FIG. 12 is a cross-sectional view of the entire liquid crystal panel for illustrating a reflector in which a flattening layer is provided on a reflective layer and a voltage is applied to a transparent electrode on the flattening layer according to the tenth embodiment of the present invention. is there.

FIG. 13 is a diagram showing a state in which a reflective liquid crystal display device including a reflector having a staircase layer according to an eleventh embodiment of the present invention is mounted on a mobile phone.

FIG. 14 is a view for explaining a reflector according to the related art.

FIG. 15 is a view for explaining a method of manufacturing a reflector having an asymmetrical reflection surface according to the related art.

[Explanation of symbols]

11 reflection layer, 12 staircase layer, 12a staircase layer first layer,
12b Stepped layer second layer, 12c Stepped layer third layer, 13
Smoothing layer, 14 intermediate layer, 15 step protection layer, 20 glass substrate, 21 gate electrode, 22 gate insulating film, 2
3 amorphous silicon, 24 source / drain electrodes, 25 TFT protective film, 26 reflective layer, 30 glass substrate, 31 front glass substrate, 32 alignment film, 33 black matrix, 34 transparent electrode, 35 color filter, 36 flattening film, 37 Liquid crystal layer, 38 retardation plate, 39 polarizing plate, 41 mobile phone, 42 numeric keypad, 43 function key, 44 liquid crystal display, 50 back glass substrate, 51 asymmetric reflection surface, 52 liquid crystal layer, 53
Front glass substrate, 54 polarizing plate + retardation plate, 60 incident light, 61 reflected light B, 62 reflected light A, 101 reflecting plate, 101a convex portion, 102 substrate, 111 glass substrate, 112 resist film, 112a convex portion, 113 Photomask, 114 metal thin film, 115 reflector.

Continued on the front page (72) Inventor Yusuke Yamagata 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 2H042 BA04 BA12 BA14 BA15 BA16 DA02 DA08 DA11 DB08 DB10 DC08 DE00 2H091 FA02Y FA07X FA11X FA14Y FC10 FC26 GA01 GA03 LA12 LA16 LA17 2H092 GA17 HA04 HA05 JA24 JB07 JB58 MA10 MA13 NA27 PA12 5C094 AA01 AA24 BA03 BA43 EB02 ED11 HA08

Claims (11)

[Claims] 1. A liquid crystal layer is sandwiched between a pair of substrates provided with electrodes, and a reflector is disposed on a liquid crystal layer side of a substrate which is a back side at the time of observation. In a reflection plate of a reflection type liquid crystal panel which is shaped and directs reflected light in a specific direction, the cross section is composed of a stepped layer in which a plurality of trapezoidal or rectangular shapes are overlapped, and the surface of the stepped layer is made of a reflecting material. A reflector characterized by being covered with layers. 2. The reflector according to claim 1, wherein the stepped layer has a two-stepped shape. 3. The reflector according to claim 1, wherein the step layer has a three-step shape. 4. The reflector according to claim 1, wherein at least a part of the step layer is made of a metal material and is electrically connected to a pixel electrode. 5. The reflection plate according to claim 1, wherein the reflection layer is an electrode for applying a voltage to a liquid crystal. 6. A flattening layer is formed on the reflective layer, and an electrode for applying a voltage to a liquid crystal is formed on the flattening layer. Reflector. 7. The reflector according to claim 1, wherein a smoothing layer is provided on the step layer to make the surface shape smooth. 8. The method of manufacturing a reflection plate according to claim 7, wherein the smoothing layer is formed by uniformly applying the smoothing layer, and then baking at a high temperature in an inclined state to solidify. A method for manufacturing a reflector, which is formed. 9. The method of manufacturing a reflection plate according to claim 7, wherein the smoothing layer is formed by uniformly applying the smoothing layer and then partially removing the smoothing layer using photolithography. And baking at a high temperature for solidification. 10. The method of manufacturing a reflection plate according to claim 1, wherein at least a part of the stepped layer is formed simultaneously with a signal wiring or a switching element. Characteristic method of manufacturing a reflector. 11. A portable device equipped with a reflection type liquid crystal display device provided with the reflection plate according to claim 1, 2, 3, 4, 5, 6, or 7.