JP3595549B2 - Reflector and reflective liquid crystal display - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a reflector having uniform brightness and whiteness over a wide range, and a reflective liquid crystal display device using the reflector.
[0002]
[Prior art]
2. Description of the Related Art In recent years, a reflection type liquid crystal display device has been widely used as a display unit of a handy type computer or the like because of particularly low power consumption. This reflective liquid crystal display device includes a reflector for reflecting light incident from the display surface side to perform display. As a conventional reflector, a reflector having a mirror-finished surface or a reflector having random irregularities formed on the surface has been used.
Among them, as shown in FIG. 9, a conventional reflector 60 having a random uneven surface is formed by heating a polyester film 61 having a thickness of 300 to 500 μm, for example, so that the surface thereof has a height of several μm. An irregular surface 61a is formed, and a reflective film 62 made of aluminum, silver, or the like is formed on the irregular surface 61a by using a method such as vapor deposition.
[0003]
As shown in FIG. 10, a conventional reflection type liquid crystal display device using a reflection plate 60 of this type is provided with transparent electrode layers 53 and 54 on opposite sides of a pair of glass substrates 51 and 52, respectively. Liquid crystal alignment films 55 and 56 are provided on each of the transparent electrode layers 53 and 54, and a liquid crystal layer 57 is provided between the alignment films 55 and 56. Then, first and second polarizing plates 58 and 59 are provided outside the glass substrates 51 and 52, respectively. A reflecting plate 60 is provided outside the second polarizing plate 59 and the surface on the side of the reflecting film 62 is second polarized light. It is attached to the plate 59 side.
[0004]
In the reflection type liquid crystal display device 50 having the above-described configuration, the light incident on the first polarizing plate 58 is linearly polarized by the polarizing plate 58, and the polarized light is elliptically polarized by transmitting through the liquid crystal layer 57. Then, the elliptically polarized light is linearly polarized again by the second polarizing plate 59, and the linearly polarized light is reflected by the reflecting plate 60, and again passes through the second polarizing plate 59 and the liquid crystal layer 57. Out of the first polarizing plate 58.
[0005]
The reflection plate and the reflection type liquid crystal display device have the following reflection characteristics.
For example, as shown in FIG. 9, the incident angle of the incident light J from the point light source disposed on the reflective film 62 is fixed at an incident angle of 30 degrees with respect to the normal to the surface of the reflective film 62, and the reflection angle of the reflected light K is When the reflectance is measured when θ is changed from 0 ° to 60 °, the reflectance at the reflection angle of 30 ° is a peak, and the reflectance is almost the lowest when the left and right reflection angles are 20 ° or less and 40 ° or more. I understood. This tendency is the same not only when measuring the reflection plate alone but also when measuring the entire liquid crystal display device including the reflection plate. The reflection angle at a reflection angle of 30 degrees is a peak and the reflection angle is 23 degrees. It has been found that the temperature drops to almost 0% in the range from below to 37 degrees or more.
[0006]
In addition, as for the reflection characteristics of a reflector having a mirror-finished surface, the reflectance generally shows a very high reflectance at a specific reflection angle with respect to the incident angle, as compared with a reflection plate having random irregularities on the surface. However, it has the characteristic that the range of the reflection angle with high reflectance is extremely narrow, that is, the viewing angle is narrow.
[0007]
[Problems to be solved by the invention]
As described above, the conventional reflector having a random uneven reflection surface has a low reflectance as a whole due to poor reflection efficiency, and the need for a reflector that efficiently reflects incident light at a wider range of reflection angles is needed. Couldn't respond enough. Therefore, the reflection type liquid crystal display device using this type of reflection plate has a problem that the viewing angle is narrow in the range of about 25 to 35 degrees and the brightness of the display surface is not sufficient. The characteristics of the reflector require whiteness as well as brightness.However, this type of conventional reflector does not uniformly reflect light of various wavelengths in a well-balanced manner. Met. Furthermore, the reflection characteristics such as the reflection angle and the reflected light intensity of this type of reflection plate are determined automatically by irregularities formed at random, and are not controlled by optical design.
[0008]
Therefore, in order to solve these problems, a reflector having a large number of stripe grooves extending linearly on the surface has been proposed. However, in the case of this reflector, in the direction perpendicular to the stripe groove, although a desired brightness can be obtained at a certain range of reflection angle, the reflection angle range is narrow, and further in the direction other than the direction perpendicular to the stripe groove. In addition, the reflectance was originally low and the reflection angle was extremely narrow. Therefore, when this type of reflector is applied to a liquid crystal display device, the above-mentioned problems, such as a narrow viewing angle and insufficient brightness and whiteness of the display surface, particularly in a direction parallel to the stripe groove, can be solved. Did not.
[0009]
The present invention has been made in order to solve the above problems, and a reflector capable of obtaining high reflection efficiency over a wide angle, and a wide field of view in any direction by using such a reflector. It is an object of the present invention to provide a reflective liquid crystal display device having corners and a brighter display surface.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the reflector of the present invention is such that the inner surface of the reflector forms a part of a spherical surface on the reflector surface, and a spherical indenter at the tip is pressed at a random pitch and a random depth. A plurality of recesses individually formed and defined by the shape of the indenter are continuously formed, and the depth of the recesses is randomly formed in a range of 0.1 to 3 μm, and the pitch of the adjacent recesses is 5 to be randomly arranged in the range of 50 [mu] m, the inclination angle of the recess inner surface is characterized in that it is set up to the diffusion angle of the reflected light within a predetermined angle.
The reflector of the present invention is formed individually by pressing an indenter having a spherical shape at the tip with a random pitch and a random depth, and the inner surface of the reflector forms a part of a spherical surface on the reflector surface. a plurality of recesses defined by is formed continuously, the depth of the recess is 0. formed randomly range from 1 to 3 [mu] m, randomly arranged in the range of the pitch between adjacent concave portions is not 5 50 [mu] m The patterned pattern is repeatedly arranged to form a reflector surface, and the diffusion angle of the reflected light is set to be within a predetermined angle on the entire reflector surface, and the concave portion is randomly formed on the entire reflector surface. To be formed is characterized in that a pattern in which recesses having a plurality of depths, a plurality of different pitches, and a plurality of different radii are individually formed in regions defined by vertical and horizontal rows is repeatedly and continuously formed. You.
The reflector according to the present invention is characterized in that the inclination angle of the inner surface of the concave portion shows a constant distribution in a range of -10 degrees to +10 degrees.
The reflector according to the present invention is characterized in that the inclination angle of the inner surface of the concave portion is set in a range of -18 to +18 degrees.
The reflector of the present invention is characterized in that the concave portion is formed on the surface of the photosensitive resin layer, and a reflective film is formed along the concave portion of the photosensitive resin layer.
[0011]
In the reflector of the present invention, a large number of concave portions having an inner surface that forms a part of a spherical surface are formed on the surface, and parameters such as the depth of the concave portions and the pitch between adjacent concave portions are set in the above ranges. By doing so, the inclination angle of the inner surface of the concave portion (inclination angle in a minute unit area), which is considered to dominate the reflection angle of the reflected light, shows a constant distribution within a certain angle range. Since the inner surface of the concave portion has a spherical shape, the constant inclination angle distribution is realized not only in a specific direction but also in all directions in the reflector. Therefore, according to the reflector of the present invention, high reflection efficiency can be obtained uniformly in all directions, and light having various wavelengths can be reflected with good balance. That is, it is possible to realize a brighter and whiter reflector when viewed from any direction as compared with a conventional reflector.
[0012]
Note that the “depth of the recess” is the distance from the reflector surface to the bottom of the recess, and the “pitch between adjacent recesses” is the distance between the centers of the recesses that is circular when viewed in plan. . Further, as shown in FIG. 8, the “inclination angle of the inner surface of the concave portion” refers to a horizontal plane of the inclined surface within the minute range when a minute range of 0.5 μm width is taken at an arbitrary position on the inner surface of the concave portion 4. Angle θ with respect to The positive and negative of the angle θ are defined, for example, that the right slope in FIG. 8 is positive and the left slope in FIG.
[0013]
As described above, regarding the depth of these recesses, the pitch of the adjacent recesses, and the inclination angle of the inner surface of the recesses, the depth of the recesses is 0.1 to 3 μm, the pitch of the adjacent recesses is 5 to 50 μm, and the inclination of the inner surface of the recesses. It is desirable to set the angle in the range of -18 to +18 degrees.
In particular, it is important to set the inclination angle distribution in the range of −18 to +18 degrees, and to arrange the pitch of the adjacent concave portions at random in all directions in the plane. This is because if there is regularity in the pitch between adjacent concave portions, there is a problem that interference colors of light appear and reflected light is colored. On the other hand, if the inclination angle distribution of the inner surface of the concave portion exceeds the range of -18 to +18 degrees, the diffusion angle of the reflected light becomes too wide, the reflection intensity decreases, and a bright reflector cannot be obtained. In the liquid crystal display device, the reflection intensity peak inside the liquid crystal display device decreases, and the total reflection loss increases).
If the depth of the concave portion exceeds 3 μm, the top of the convex portion cannot be filled with the flattening film when the concave portion is flattened in a later step, and desired flatness cannot be obtained.
When the pitch of the adjacent concave portions is less than 5 μm, there is a restriction in the production of the reflector forming matrix, the processing time becomes extremely long, a shape which can obtain desired reflection characteristics cannot be formed, and interference light is generated. Problems occur. Further, in practice, when a diamond indenter having a diameter of 30 to 100 μm that can be used for manufacturing a reflector forming master is used, it is desirable that the pitch between adjacent concave portions is 5 to 50 μm.
[0014]
Further, in the reflection type liquid crystal display device of the present invention, a large number of recesses whose inner surface forms a part of a spherical surface are formed on the reflector, that is, the reflector surface, and the depth of the recesses is 0.1 to 3 μm. And a reflector having a pitch between adjacent concave portions of 5 to 50 μm and an inclination angle of the inner surface of the concave portion of −18 to +18 degrees. The reflector may be installed in either an external type installed outside the liquid crystal cell or a built-in type installed inside the substrate of the liquid crystal cell.
[0015]
According to the reflection-type liquid crystal display device of the present invention, since the reflection type liquid crystal display device has the above-described reflector, the reflector itself has high reflection efficiency in all directions and has a characteristic of reflecting light having various wavelengths in a well-balanced manner. In addition, the viewing angle can be widened and the display surface can be made brighter as compared with the conventional reflection type liquid crystal display device.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a diagram showing a reflector according to the present embodiment. As shown in this figure, a reflector 1 of the present embodiment has a flat resin substrate 3 (a substrate for a reflector) made of a photosensitive resin layer or the like provided on a substrate 2 made of, for example, glass. A large number of concave portions 4 whose inner surfaces form a part of a spherical surface are continuously formed so as to overlap each other, and a reflective film 5 made of a thin film of, for example, aluminum or silver is formed thereon by vapor deposition or printing. It is a thing.
[0017]
The depth of the recesses 4 is randomly formed in the range of 0.1 to 3 μm, the pitch of the adjacent recesses 4 is randomly arranged in the range of 5 to 50 μm, and the inclination angle of the inner surface of the recess 4 is −18 to +18. It is desirable to set in the range of degrees.
In particular, it is important that the inclination angle distribution of the inner surface of the recess 4 is set in the range of −18 to +18 degrees, and that the pitch of the adjacent recesses 4 is randomly arranged in all directions in the plane. This is because if the pitch of the adjacent concave portions 4 is regular, there is a problem that interference colors of light appear and reflected light is colored. On the other hand, if the inclination angle distribution of the inner surface of the concave portion 4 exceeds the range of −18 to +18 degrees, the diffusion angle of the reflected light becomes too wide, the reflection intensity decreases, and a bright reflector cannot be obtained. This is because the temperature becomes 36 degrees or more in air, the reflection intensity peak inside the liquid crystal display device decreases, and the total reflection loss increases.)
If the depth of the concave portion 4 exceeds 3 μm, the top of the convex portion cannot be filled with the flattening film when the concave portion 4 is flattened in a later step, and desired flatness cannot be obtained.
When the pitch of the adjacent concave portions 4 is less than 5 μm, there is a restriction in the production of the reflector forming matrix, the processing time becomes extremely long, a shape that can obtain the desired reflection characteristics cannot be formed, and interference light is generated. And other problems arise. Further, in practice, when a diamond indenter having a diameter of 30 to 100 μm that can be used for manufacturing a reflector forming base is used, it is desirable that the pitch between adjacent concave portions 4 is 5 to 50 μm.
[0018]
Next, a method of manufacturing the reflector having the above configuration will be described with reference to FIGS.
First, as shown in FIG. 2A, a flat plate-shaped base material 7 made of, for example, brass, stainless steel, tool steel, or the like is fixed on a table of a rolling device. Then, the surface of the matrix base material 7 is pressed by a spherical diamond indenter 8 having a predetermined diameter R at the tip, and the matrix base material 7 is moved in the horizontal direction, and the diamond indenter 8 is moved up and down to press. By repeating this operation many times, a large number of recesses 7a having different depths and arrangement pitches are rolled on the surface of the matrix base material 7, and are formed with the reflector forming matrix 9 as shown in FIG. I do. As shown in FIG. 3, in the rolling device used here, the table for fixing the matrix substrate 7 moves in the X and Y directions in the horizontal plane with a resolution of 0.1 μm, and the diamond indenter 8 has a resolution of 1 μm. Has a function of moving in the vertical direction (Z direction). The diameter R of the tip of the diamond indenter 8 is desirably about 20 to 100 μm. For example, when the depth of the recess 7a is about 2 μm, the diameter R is preferably 30 to 50 μm, and when the depth of the recess 7a is about 1 μm, the diameter R is preferably 50 to 100 μm.
[0019]
The procedure of rolling with a diamond indenter is as follows.
FIG. 4 is a plan view showing a rolling pattern. As shown in FIG. 4, pitches of adjacent recesses in one horizontal row are t1 (= 17 μm), t3 (= 15 μm), and t2 (= 16 μm), t3, t4 (= 14 μm), t4, t5 (= 13 μm), t2, t3, and t3. In addition, the pitches of the concave portions adjacent to each other in one vertical line have the same pattern in order from the top. By pressing four different depths in the range of 1.1 to 2.1 μm (shown as d1, d2, d3, and d4 in the drawing), the radius of the circular concave portion as an indentation after the pressing is also reduced. r1 (= 11 μm), r2 (= 10 μm), r3 (= 9 μm), and r4 (= 8 μm). For example, the radii of the concave portions in one vertical line are r1, r2, r3, r1, r4, r2, r4, r3, r1, r4, r1 in order from the top.
[0020]
In addition, as the actual order of the rolling, for example, in the uppermost horizontal row, after all of the recesses having the depth d1 are formed at intervals, then the recesses having the depth d2, the recesses having the depth d3, and the depth d4 are formed. The rolling operation with a depth of four patterns is repeated so as to form the recesses of the first pattern, and first, all the recesses in the uppermost row in a horizontal row are formed. After that, it moves to the second horizontal row from the top and repeats the same operation. Thus, all the concave portions in the pattern are formed. FIG. 4 shows a rolling pattern of t = 150 μm square, and the entire reflector is formed by repeating this pattern. As shown in FIG. 4, since the impressions of the adjacent concave portions partially overlap, the planar shape of the entire concave portion after all the rolling operations are completed is as shown in FIG.
[0021]
Thereafter, as shown in FIG. 2 (c), the matrix 9 is housed and placed in a box-shaped container 10, a resin material 11 such as silicone is poured into the container 10, and left and cured at room temperature. The removed resin product is taken out of the container 10 and unnecessary portions are cut off, and as shown in FIG. 2D, the resin product has a large number of concave portions forming the mold surface of the matrix 9 and a large number of convex portions having the opposite concave and convex shape. The transfer mold 12 having the mold surface 12a is created.
[0022]
Next, a photosensitive resin liquid such as an acrylic resist, a polystyrene resist, an azide rubber resist, or an imide resist is applied to the upper surface of the glass substrate by a coating method such as a spin coating method, a screen printing method, and a spraying method. After the application, the photosensitive resin liquid on the substrate is pre-baked by using a heating device such as a heating furnace or a hot plate in a temperature range of, for example, 80 to 100 ° C. for 1 minute or more, and the photosensitive resin is applied on the substrate. Form a layer. However, since the prebaking conditions vary depending on the type of the photosensitive resin used, it is needless to say that the treatment may be performed at a temperature and time outside the above range. The thickness of the photosensitive resin layer formed here is preferably in the range of 2 to 5 μm.
[0023]
Thereafter, as shown in FIG. 2E, the transfer mold 12 shown in FIG. 2D is used, and the mold surface 12a of the transfer mold 12 is pressed against the photosensitive resin layer 3 on the glass substrate for a predetermined time. Then, the transfer mold 12 is removed from the photosensitive resin layer 3. In this way, as shown in FIG. 2F, the convex portions of the transfer mold surface 12a are transferred to the surface of the photosensitive resin layer 3 to form a large number of concave portions 4. Also, pressing pressure is preferred to select a value for the type of the photosensitive resin to be used at the time of embossing, it is for example to a 30 to 50 kg / cm ² pressure of about. As for the pressing time, it is preferable to select a value suitable for the type of the photosensitive resin to be used, for example, about 30 seconds to 10 minutes.
[0024]
Thereafter, a light beam such as an ultraviolet ray (g, h, i-line) for curing the photosensitive resin layer 3 is irradiated from the rear surface side of the transparent glass substrate to cure the photosensitive resin layer 3. In the case of a photosensitive resin layer of the type described above, the intensity of 50 mJ / cm ² or more is sufficient to cure the photosensitive resin layer. Depending on the case, it is needless to say that irradiation may be performed at other intensity. Then, the photosensitive resin layer 3 on the glass substrate is post-baked by heating the photosensitive resin layer 3 on the glass substrate at, for example, about 240 ° C. for 1 minute or more by using a heating device such as a heating furnace or a hot plate similar to that used in the pre-baking. Is baked.
[0025]
Finally, for example, aluminum is formed on the surface of the photosensitive resin layer 3 by electron beam evaporation or the like, and the reflection film 1 is formed along the surface of the concave portion, thereby completing the reflector 1 of the present embodiment.
[0026]
In the reflector 1 of the present embodiment, a large number of recesses 4 whose inner surfaces are part of a spherical surface are formed on the surface, and the values of the depth of the recesses 4, the pitch of the adjacent recesses 4, and the like are set as described above. Is set, the inclination distribution of the inner surface of the concave portion shows a constant distribution in a certain angle range. As an example, FIG. 6 shows the distribution of the inclination angle of the inner surface of the concave portion in the reflector 1 of the present embodiment. The horizontal axis indicates the inclination angle, and the vertical axis indicates the frequency at which the inclination angle exists. As shown in this figure, the inclination angle shows a substantially constant distribution in the range of -18 to +18 degrees, particularly in the range of -10 to +10 degrees. Further, since the inner surface of the concave portion 4 is spherical and symmetrical with respect to all directions, this constant inclination angle distribution is realized not only in a specific direction but also in all directions in the reflector.
It is considered that the inclination angle of the inner surface of the concave portion governs the reflection angle of the reflected light on the inner surface of the concave portion, and in the case of the present embodiment, since the inclination angle distribution is constant in all directions of the reflector, As a result, uniform reflection angles and reflection efficiencies can be obtained, and light having various wavelengths can be reflected in a well-balanced manner. That is, it is possible to realize a brighter and whiter reflector when viewed from any direction as compared with a conventional reflector.
[0027]
In addition, when the master 9 for forming the reflector is manufactured, the diamond indenter 8 and the mother substrate 7 are simply moved by moving the diamond indenter 8 up and down to press the surface of the mother substrate 7. No rubbing. As a result, the surface condition of the tip of the diamond indenter 8 is reliably transferred to the matrix 9 side, and if the tip of the indenter 8 is mirror-finished, the inner surface of the concave portion of the matrix 9 and, consequently, the inner surface of the concave portion of the reflector can easily be mirror-finished. can do.
Furthermore, unlike the conventional reflector in which the uneven surface is formed by heating a resin film such as polyester, the depth, diameter, pitch, and other dimensions of the recess in the reflector 1 of the present embodiment, and the inner surface of the recess are different. The surface condition and the like are all controlled, and the concave shape of the reflecting plate can be created almost as designed by using a high-precision rolling device. Therefore, according to the present method, the reflection characteristics such as the reflection angle and the reflection efficiency of the reflection plate to be produced are easier to control than in the past, and a desired reflector can be obtained.
[0028]
Note that the specific numerical values such as the depth, diameter, and pitch of the concave portion 4 of the reflector 1 in the present embodiment and the rolling pattern of the concave portion shown in FIG. 4 are merely examples, and the design can be changed as appropriate. Of course. In addition, materials of various base materials such as a base material for a reflector and a base material for a matrix, and a constituent material of a transfer mold can be appropriately changed.
[0029]
Next, a reflective liquid crystal display device of the STN (Super Twisted Nematic) type including the above-described reflector will be described.
As shown in FIG. 7, this reflection type liquid crystal display device has a liquid crystal layer 15 provided between a pair of display side glass substrates 13 and a rear side glass substrate 14 having a thickness of, for example, 0.7 mm. A single retardation plate 16 made of a polycarbonate resin, a polyarylate resin, or the like is provided on the upper surface side of the substrate, and a first polarizing plate 17 is disposed on the upper surface side of the retardation plate 16. The second polarizing plate 18 and the reflector 1 of the present embodiment shown in FIG. 1 are sequentially provided on the lower surface side of the rear glass substrate 14.
[0030]
The reflector 1 is mounted such that the surface on which the concave portion 4 is formed faces the lower surface side of the second polarizing plate 18, and between the second polarizing plate 18 and the reflector 1, light such as glycerin is applied. An adhesive 19 made of a material that does not adversely affect the refractive index is filled.
Transparent electrode layers 20 and 21 made of ITO (indium tin oxide) or the like are formed on the opposing surfaces of the two glass substrates 13 and 14, respectively, and an alignment film 22 made of a polyimide resin or the like is formed on the transparent electrode layers 20 and 21. 23 are provided. The liquid crystal in the liquid crystal layer 15 is twisted 240 degrees due to the relationship between the alignment films 22 and 23 and the like.
[0031]
Further, a color filter (not shown) may be formed between the rear glass substrate 14 and the transparent electrode layer 21 by printing or the like, so that the liquid crystal display device can perform color display.
[0032]
In the liquid crystal display device according to the present embodiment, as described above, since the reflector 1 itself has the characteristic that the reflection angle of incident light is wide in all directions and the reflection efficiency is high, the user can change the display surface. When viewed from any direction, the viewing angle is wider than that of the conventional liquid crystal display device, and a bright display surface can be obtained.
[0033]
In the reflection type liquid crystal display device of the present embodiment, an example has been described in which the reflection plate is disposed outside the second polarizing plate, that is, a so-called external reflection plate is provided. It may be disposed on the side to be a built-in type. Although the STN type liquid crystal display device has been described as an example of the liquid crystal display device, the reflector of the present invention is also applied to a TN (Twisted Nematic) type liquid crystal display device in which the twist angle of liquid crystal molecules in the liquid crystal layer is set to 90 degrees. Of course, you can.
[0034]
【The invention's effect】
As described in detail above, in the reflector of the present invention, the inner surface is formed as a part of a spherical surface, and the indenter having the spherical end is pressed at a random pitch and a random depth to be individually formed. A plurality of recesses defined by the shape of the indenter are formed on the surface, and the depth of the recesses, the pitch between adjacent recesses, and the like are defined, so that the inclination of the inner surface of the recesses with respect to all directions of the reflector. Since the angular distribution is substantially constant in a certain angle range, uniform reflection efficiency can be obtained in all directions, and light having various wavelengths can be reflected with good balance. That is, it is possible to realize a brighter and whiter reflector when viewed from any direction as compared with a conventional reflector.
According to the reflection type liquid crystal display device of the present invention, a liquid crystal display device having a wide viewing angle and a bright display surface can be realized by including the reflector having the above excellent characteristics.
In the present invention, a large number of concave portions having an inner surface that forms a part of a spherical surface are formed so as to overlap the end portions on the surface, the depth of the concave portions is defined, and the pitch between adjacent concave portions is 5 to 50 μm. Random in a range, and that the concave portion is formed randomly on the entire surface of the reflector means that concave portions having a plurality of depths, a plurality of different pitches, and a plurality of different radii are individually formed in regions defined by vertical and horizontal rows. Since the entire surface is formed by repeatedly forming the formed pattern continuously, the pattern in which the inclination angle distribution of the inner surface of the concave portion is almost constant within a certain angle range with respect to all directions of the reflector is repeatedly arranged. The entire reflector surface can be configured.
In the present invention, a reflector having a flattened surface can be obtained by providing a reflective film and a flattening film. In this case, by setting the depth of the concave portion to be in the range of 0.1 to 3 μm, the flattening film can be filled and flattened, and desired flatness can be obtained.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a reflector according to an embodiment of the present invention.
FIG. 2 is a process flow chart showing a manufacturing process of the reflector in order.
FIG. 3 is a view showing a process of manufacturing a matrix used for forming a reflector, showing a state in which the matrix substrate is pressed by a diamond indenter.
FIG. 4 is a plan view showing a pattern of rolling by a diamond indenter in the same manufacturing process of the mother die.
FIG. 5 is a plan view showing the shape of the entire concave portion after rolling.
FIG. 6 is a diagram showing the distribution of the inclination angle of the inner surface of the concave portion in the reflector.
FIG. 7 is a sectional view showing a reflective liquid crystal display device according to an embodiment of the present invention.
FIG. 8 is a view for explaining an inclination angle of an inner surface of a concave portion of the reflector according to the present invention.
FIG. 9 is a perspective view showing an example of a conventional reflector.
FIG. 10 is a cross-sectional view illustrating an example of a conventional reflective liquid crystal display device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Reflector 2 Substrate 3 Resin base material (reflector base material)
Reference Signs List 4 concave portion 5 reflective film 7 matrix base material 8 diamond indenter 9 reflector forming matrix 12 transfer mold

Claims (6)

The inner surface of the reflector surface forms a part of a spherical shape, and a plurality of indenters having a spherical shape at the tip are individually formed by pressing the indenter at a random pitch and a random depth, and a plurality of indenters determined by the shape of the indenter The recesses are formed continuously, the depths of the recesses are randomly formed in the range of 0.1 to 3 μm, the pitch of the adjacent recesses is randomly arranged in the range of 5 to 50 μm, and the inclination of the inner surface of the recess is formed. reflector, characterized in that the corner has been set up to the diffusion angle of the reflected light within a predetermined angle. The inner surface of the reflector surface forms a part of a spherical shape, and a plurality of indenters having a spherical shape at the tip are individually formed by pressing the indenter at a random pitch and a random depth, and a plurality of indenters determined by the shape of the indenter are formed. The recesses are formed continuously, and the depth of the recesses is zero. . A reflector surface is formed by repeatedly forming patterns randomly formed in a range of 1 to 3 μm, and randomly arranged in a range of a pitch of 5 to 50 μm between adjacent concave portions. While the diffusion angle is set to be within a predetermined angle, and the concave portions are randomly formed on the entire surface of the reflector, it means that the concave portions having a plurality of depths, a plurality of different pitches, and a plurality of different radii are individually formed. A reflector characterized in that a pattern formed in a region defined by vertical and horizontal rows is repeatedly and continuously formed. 3. The reflector according to claim 1, wherein the inclination angle of the inner surface of the concave portion shows a constant distribution in a range of −10 degrees to +10 degrees. 4. The reflector according to any one of claims 1 to 3, wherein an inclination angle of the inner surface of the concave portion is set in a range of -18 to +18 degrees. The reflector according to any one of claims 1 to 4 , wherein the concave portion is formed on a surface of the photosensitive resin layer, and a reflective film is formed along the concave portion of the photosensitive resin layer. A reflective liquid crystal display device comprising the reflector according to claim 1.

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