TWI727481B - Optical film - Google Patents

Abstract

The optical film comprises a substrate and a pattern layer. The pattern layer is on the substrate. The pattern layer comprises strips extending along different directions. The strips are defined by convex portions or concave portions of a surface of the pattern layer.

Description

Optical film

The present invention relates to an optical film, a display device and a manufacturing method thereof, and particularly relates to an optical film, a display device and a manufacturing method thereof for improving visual effects.

The liquid crystal display includes a polarizing plate, a liquid crystal panel, and a backlight unit. In order to improve the color quality and contrast ratio at the side of the liquid crystal display, various attempts have been made to develop an improved liquid crystal panel or liquid crystal structure. However, the modification of the liquid crystal panel has limitations on the improvement of the color quality and the contrast ratio at the side of the liquid crystal display, and requires a complicated process. In addition, as the screen size of the liquid crystal display increases, the brightness uniformity of the liquid crystal display continues to decrease. Therefore, a separate liquid crystal display module must be provided depending on the screen size, thereby reducing processability and economic feasibility.

The invention relates to an optical film, a display device and a manufacturing method thereof. The optical film can be used to improve the visual/display effect of the display device.

According to the first aspect of the present invention, an optical film is provided. The optical film includes a substrate and a pattern layer. The pattern layer is on the substrate. The pattern layer includes several stripes extending in different directions. The stripes are defined by the raised or recessed parts of the surface of the pattern layer.

According to the second aspect of the present invention, a display device is provided. The display device uses an optical film. The optical film includes a substrate and a pattern layer. The pattern layer is on the substrate. The pattern layer includes several stripes extending in different directions. The stripes are defined by the raised or recessed parts of the surface of the pattern layer.

According to a third aspect of the present invention, a method for manufacturing an optical film is provided, which includes forming a pattern layer on a substrate using a roller transfer method.

In order to have a better understanding of the above and other aspects of the present invention, the following specific examples are given in conjunction with the accompanying drawings to describe in detail as follows:

102, 202: display device

170: LCD monitor

171: Backlight module

172: LCD panel

173: Lower polarizer

174: upper polarizer

175: Thin Film Transistor Substrate

176: liquid crystal layer

177: Color filter substrate

178: Orientation film

179: Orientation film

106, 206: optical film

108: Substrate

110: pattern layer

110S: surface

112: Adhesive layer

214: Rhombus Mirror Layer

214A: Rhombus structural unit

750: Wheel

752: curved outer surface

754: wheel

756: Axle

A: distance

B: distance

C1, C2: Engraving depth

D1: First direction

D2: second direction

D3: Third party

D4: Fourth direction

F: Spacing

h: height

H: height

K: spacing

M: line width

N: spacing

O: round outline

P1: The first pattern area

P2: The second pattern area

P3: The third pattern area

P4: The fourth pattern area

Q: Spacing

Tu: Striped carved pattern

Tp: circular engraved pattern

U1: first stripe

U2: second stripe

U3: third stripe

U4: fourth stripe

Z: direction

FIG. 1 is a cross-sectional view of a display device according to an embodiment.

FIG. 2 is a partial enlarged view of an optical film according to an embodiment.

FIG. 3 is a partial enlarged view of an optical film according to an embodiment.

FIG. 4 is a schematic diagram of the striped surface facing the pattern layer according to an embodiment.

FIG. 5 is a schematic diagram of the striped surface facing the pattern layer according to an embodiment.

FIG. 6 is a schematic diagram of the striped surface facing the pattern layer according to an embodiment.

FIGS. 7A to 8B illustrate a method of manufacturing a roller for forming a pattern layer according to an embodiment.

FIG. 9 is a cross-sectional view of a display device according to an embodiment.

FIG. 10 is a partially enlarged view of an optical film according to an embodiment.

FIG. 11 is a partial enlarged view of an optical film according to an embodiment.

The following is a description with some embodiments. It should be noted that this disclosure does not show all possible embodiments, and other implementation aspects not mentioned in this disclosure may also be applicable. Furthermore, the size ratios in the drawings are not drawn in proportion to the actual products. Therefore, the contents of the description and the illustrations are only used to describe the embodiments, rather than to limit the protection scope of this disclosure. In addition, the descriptions in the embodiments, such as detailed structure, process steps, material applications, etc., are for illustrative purposes only, and are not intended to limit the scope of protection of the present disclosure. The details of the steps and structures of the embodiments can be changed and modified according to the needs of the actual application process without departing from the spirit and scope of the present disclosure. In the following description, the same/similar symbols represent the same/similar elements.

FIG. 1 shows a cross-sectional view of a display device 102 according to an embodiment. The display device 102 includes a liquid crystal display 170 and an optical film 106 stacked in the Z direction. The liquid crystal display 170 includes a backlight module 171, a liquid crystal panel 172, a lower polarizing plate 173 and an upper polarizing plate 174. The liquid crystal panel 172 is disposed on the backlight module 171 and includes, for example, a thin film transistor substrate 175, a liquid crystal layer 176, a color filter substrate 177, and To the film 178 and 179. The alignment film 179 can be arranged on the color filter substrate 177, the alignment film 178 can be arranged on the thin film transistor substrate 175, the liquid crystal layer 176 can be arranged between the alignment films 178 and 179, and the lower polarizer 173 can be arranged on the thin film transistor. Between the crystal substrate 175 and the backlight module 171 (the light-incident side of the liquid crystal panel 172), the upper polarizer 174 can be arranged on the color filter substrate 177 (the light-emitting side of the liquid crystal panel 172), and the optical film 106 can be arranged on the upper polarizer. On the light exit side of the board 174.

The optical film 106 may include a substrate 108 and a pattern layer 110. The pattern layer 110 is on the substrate 108. The optical film 106 can be attached to the liquid crystal display 170 by using the adhesive layer 112 with the surface 110S of the pattern layer 110 facing the liquid crystal display 170. The adhesive layer 112 may include a solid transparent optical adhesive (Optically Clear Adhesive; OCA) or a liquid transparent optical adhesive (Optically Clear Resin, OCR) or the like.

In one embodiment, the substrate 108 is a transparent substrate. The material of the substrate 108 may be selected from transparent resins, such as polyethylene terephthalate (PET), polymethylmethacrylate (PMMA), and cellulose called triacetate cellulose (triacetate cellulose, TAC), cyclo olefin polymers (COP).

2 and 3 show partial enlarged views of the optical film 106 according to different embodiments. In Figure 2, the surface 110S of the pattern layer 110 is distributed with convex parts having a flat surface and concave parts between the convex parts. In Fig. 3, the surface 110S of the pattern layer 110 has raised portions including wave shapes and recessed portions between the raised portions. In an embodiment, the height h of the protruding portion may be 3 μm-25 μm, for example, 3 μm-5 μm, 10 μm-15 μm, 20-25 μm.

FIG. 4, FIG. 5, and FIG. 6 respectively show schematic diagrams when facing the striped surface 110S of the pattern layer 110 according to different embodiments.

In Figure 4, the surface 110S of the pattern layer 110 includes a first pattern area P1, a second pattern area P2, a third pattern area P3, and a fourth pattern area P4. The first pattern area P1 includes a plurality of first stripes U1, all of which have a first extension direction (for example, the extension direction is parallel to the first direction D1), and can be in a direction substantially perpendicular to the first extension direction (for example, the first extension direction). The two directions D2) are arranged separately from each other. The second pattern area P2 includes a plurality of second stripes U2, all of which have a second extension direction (for example, the extension direction is parallel to the second direction D2), and can be in a direction substantially perpendicular to the second extension direction (for example, the first extension direction). In a direction D1), they are arranged separately from each other. The third pattern area P3 includes a plurality of third stripes U3, all of which have a third extension direction (for example, the extension direction is parallel to the third direction D3), and can be substantially perpendicular to the third extension direction in a direction (for example, the third extension direction). The four directions D4) are arranged separately from each other. The fourth pattern area P4 includes a plurality of fourth stripes U4, all of which have a fourth extension direction (for example, the extension direction is parallel to the fourth direction D4), and can be arranged in a direction substantially perpendicular to the fourth extension direction (for example, the fourth extension direction). The three directions D3) are arranged separately from each other. In one embodiment, the acute angle defined by the extension line and the intersecting point of the third direction D3 and the first direction D1 may be substantially 45 degrees. The acute angle defined by the extension line and the intersecting point of the third direction D3 and the second direction D2 may be substantially 45 degrees. The relationship between the fourth direction D4 and other directions can be deduced by analogy. The first direction D1, the second direction D2, the third direction D3, and the fourth direction D4 are all substantially perpendicular to the Z direction.

In Figure 4, the pattern area of this example has a circular outline O. For example, in the first pattern area P1, the first strips arranged in the second direction D2 The length of the pattern U1 (that is, the size in the first direction D1) may gradually become longer and then gradually become shorter, so that the outer edge of the first stripe U1 can define a circular outline O as indicated by a circular dashed line. Alternatively, the short edge of the first stripe U1 may be aligned with the circular outer edge of the circular contour O. The circular contour O of other pattern areas such as the second pattern area P2, the third pattern area P3 and the fourth pattern area P4 can be deduced by analogy. In one embodiment, the circumference of the pattern area (or the circular outline O) is about 80-90 μm.

In FIG. 4, the first pattern area P1, the second pattern area P2, the third pattern area P3, and the fourth pattern area P4 can be regularly arranged in the arrangement unit indicated by the hexagonal dotted line. In the arrangement unit, with the first pattern area P1 as the center, the second pattern area P2 is located on the opposite side of the first pattern area P1 in the second direction D2; the third pattern area P3 is located in the first pattern area P1 in the second direction D2. On the opposite side in a direction D1; the fourth pattern area P4 is located on the opposite side of the first pattern area P1 in the first direction D1; and the third pattern area P3 and the fourth pattern area P4 are divided by the first pattern area P1 and the second pattern area P1. The line connecting the centers of the two pattern areas P2 is a mirror image configuration of the axis of symmetry. For example, the distance K between the pattern areas (that is, the distance K between the circular outlines O) may be 90 μm to 110 μm. The line width M of the stripes can be 5μm~25μm. The spacing N of the stripes in the pattern area may be 10 μm to 40 μm.

In FIG. 5, the first pattern area P1, the second pattern area P2, the third pattern area P3, and the fourth pattern area P4 can be regularly arranged in the arrangement unit indicated by the dotted line. In the arrangement unit, with the first pattern area P1 as the center, the second pattern area P2 is located on the opposite side of the first pattern area P1 in the second direction D2; the third pattern area P3 is located in the first pattern area P1 in the second direction D2. The opposite side in the three directions D3; And the fourth pattern area P4 is located on the opposite side of the first pattern area P1 in the fourth direction D4.

In Figure 6, the first stripe U1 may have a first extension direction (for example, the extension direction is parallel to the first direction D1). The second stripe U2 may have a second extension direction (for example, the extension direction is parallel to the second direction D2). The first stripe U1 and the second stripe U2 define a series of diamond-shaped patterns extending in the third direction D3, each of the series of diamond-shaped patterns includes a number of connected diamond-shaped pattern units, and each of the diamond-shaped pattern units consists of the first stripe U1. Two of the two and two of the second stripes U2 are defined. The diagonal distance A of the diamond pattern unit in the third direction D3 may be 100 μm to 300 μm, and the diagonal distance B in the fourth direction D4 may be 40 μm to 150 μm. The spacing F of the stripes between the diamond pattern units may be 10 μm to 20 μm.

In an embodiment, the pattern layer 110 of the optical film 106 can be formed using a roller transfer method, and the roller indentation portion can cause one of the convex portion and the convex portion of the surface 110S, which forms stripes. For example, the optical film 106 may use a roller with an engraved pattern to coat the curable resin on the substrate 108, and perform a curing step on the curable resin to form the pattern layer 110. The curable resin may include a transparent resin, such as polyethylene terephthalate (PET), polymethylmethacrylate (PMMA), and cellulose called triacetate cellulose (TAC). , Cyclic olefin polymers (COP), etc.

FIGS. 7A to 8B illustrate a method of manufacturing the roller 750 for forming the pattern layer 110 according to an embodiment. Figures 7A and 8A are facing the roller A schematic top view of the curved outer surface 752 of the 750. FIGS. 7B and 8B are schematic cross-sectional views of the roller 750. The enlarged part in Figure 7B can be drawn along the line AB in Figure 7A. The enlarged part in Figure 8B can be drawn along the line AB in Figure 8A. Referring to FIGS. 7A and 7B, the roller 750 may have a wheel body 754 and a shaft 756. The shaft 756 is fixed at the center of the wheel body 754 and protrudes axially from both ends of the wheel body 754. Tools such as lasers, knives, or other suitable methods can be used to engrave (first engraving) on the curved outer surface 752 of the wheel body 754 to form a striped engraving pattern Tu. The engraving depth C1 (first engraving depth) is for example but not Limited to 10μm~15μm. Please refer to Figures 8A and 8B, and then use lasers, knives and other tools, or other suitable methods to engrave (second engraving) on the curved outer surface 752 of the wheel body 754 to form a circular engraving pattern Tp , The engraving depth C2 (the second engraving depth) is, for example, but not limited to 3 μm to 5 μm. In an embodiment, the circumference of the circular engraving pattern Tp may be about 80-90 μm, for example. Thereby, an engraving unit including the striped engraved pattern Tu and the circular engraved pattern Tp is formed, which can be used to create the pattern units shown in FIGS. 4 and 5 (for example, including the first pattern area P1 and the first stripe U1). A pattern unit of; another pattern unit including the second pattern area P2 and the second stripe U2, and so on other pattern units). The size of the engraving unit can also correspond to the pattern unit. This concept can be used to manufacture rollers for forming the pattern layer 110 of other embodiments or other elements formed by roller transfer methods.

FIG. 9 is a cross-sectional view of a display device 202 according to another embodiment. The difference from the display device 102 shown in FIG. 1 is explained as follows. As shown in FIG. 9, the optical film 206 further includes a diamond mirror layer 214. The rhombohedral mirror layer 214 is arranged on the pattern layer 110 on the surface of 110S. The optical film 206 can be attached to the image display surface of the liquid crystal display 170 by using the adhesive layer 112 with the diamond mirror layer 214 facing the liquid crystal display 170. In one embodiment, the substrate 108 is a light-transmitting substrate, and the material is the same as that described above, and the details are not repeated here.

Figures 10 and 11 show partial enlarged views of the optical film 206 according to different embodiments. The difference between the optical film 206 shown in FIG. 10 and the optical film 106 shown in FIG. 2 is that the rhombic mirror layer 214 formed on the surface 110S of the pattern layer 110 of the optical film 206 includes rhombic structure units 214A. The pitch Q of the rhombic structure unit 214A of the rhombus mirror layer 214 may be 50 μm to 70 μm. The height H of the diamond structure unit 214A may be 10 μm-50 μm. In an embodiment, the rhombohedral mirror layer 214 of the optical film 206 may be formed by a roller transfer method. For example, the diamond mirror layer 214 may use a roller with a diamond-shaped engraved pattern to coat the curable resin on the surface 110S of the pattern layer 110, and perform a curing step on the curable resin to form the diamond mirror layer 214. The engraving pattern of the roller can be engraved on the roller by using lasers, knives and other tools. The curable resin may include a transparent resin, such as polyethylene terephthalate (PET), polymethylmethacrylate (PMMA), and cellulose called triacetate cellulose (TAC). , Cyclic olefin polymers (COP), etc.

In an embodiment, the pattern layer 110 and the rhombohedral mirror layer 214 may have different refractive indexes. In one embodiment, the refractive index of the pattern layer 110 is greater than the refractive index of the rhomboid layer 214. In an embodiment, the refractive index of the pattern layer 110 may be equal to or greater than 1.60. In an embodiment, the refractive index of the diamond mirror layer 214 may be equal to or less than 1.48.

In order to make the above objectives, features, and advantages of this disclosure more obvious and understandable, the following special examples are described in detail as follows:

Example 1

Example 1 uses the display device 102 shown in Figure 1, wherein the liquid crystal display 170 uses a liquid crystal display (manufactured by AU Optronics Co., Ltd., model: T215HVN01.1), and the display device 102 uses the pattern shown in Figure 4层110。 Layer 110. Referring to Figure 4, in Example 1, the circumference of the circular contour O of the pattern area is 80μm, the distance K between the pattern areas (ie the distance K between the circular contours O) is 100μm, and the line width of the stripe is M It is 13 μm, and the spacing N of the stripes in the pattern area is 25 μm. Refer also to FIGS. 7A to 8B. In this example, the engraving depth C1 of the roller 750 used to form the pattern layer 110 is 10 μm-15 μm, and the engraving depth C2 is 3 μm-5 μm.

Example 2

Embodiment 2 is similar to Embodiment 1, the difference is that the line width M of the stripes is 10 μm, and the spacing N of the stripes in the pattern area is 20 μm.

Example 3

Embodiment 3 uses the display device 102 as shown in FIG. 1, and the display device 102 uses the pattern layer 110 as shown in FIG. 6. Referring to Fig. 6, in Embodiment 3, the diagonal distance A of the diamond pattern unit in the third direction D3 is 250 μm, and the diagonal distance B in the fourth direction D4 is 100 μm. The line width M of the stripes is 15μm, the spacing F of the stripes between the diamond pattern units is 15μm, and the height h (or the engraving of the roller Depth) is 20~25μm.

Example 4

Embodiment 4 is similar to Embodiment 3, except that the diagonal distance A of the diamond pattern unit in the third direction D3 is 150 μm, and the diagonal distance B in the fourth direction D4 is 50 μm.

Example 5

Embodiment 5 is similar to Embodiment 1, the difference is that Embodiment 5 uses the display device 202 that further includes a rhombohedral mirror layer 214 as shown in FIG. 9, wherein the condition of the pattern layer 110 of Embodiment 5 is similar to that of Embodiment 1. In Embodiment 5, the pitch Q of the diamond-shaped structural units 214A of the diamond mirror layer 214 is 50 μm, and the height H (or the engraving depth of the roller) of the diamond-shaped structural units 214A is 25 μm-30 μm.

Example 6

Embodiment 6 is similar to Embodiment 2, the difference is that Embodiment 6 uses the display device 202 that further includes a rhombohedral mirror layer 214 as shown in FIG. 9, and the condition of the pattern layer 110 of Embodiment 6 is similar to that of Embodiment 2. In Embodiment 6, the pitch Q of the diamond-shaped structural units 214A of the diamond mirror layer 214 is 50 μm, and the height H (or the engraving depth of the roller) of the diamond-shaped structural units 214A is 25 μm-30 μm.

Example 7

Embodiment 7 is similar to Embodiment 3, the difference is that Embodiment 7 uses the display device 202 that further includes a rhombohedral mirror layer 214 as shown in FIG. 9, and the condition of the pattern layer 110 of Embodiment 7 is similar to that of Embodiment 3. In Embodiment 7, the pitch Q of the rhombic structure unit 214A of the rhombus mirror layer 214 is 50 μm, and the height of the rhombus structure unit 214A The degree H (or the engraving depth of the roller) is 25μm~30μm.

Example 8

Embodiment 8 is similar to Embodiment 4, and the difference is that Embodiment 8 uses the display device 202 that further includes a rhombohedral mirror layer 214 as shown in FIG. 9, and the condition of the pattern layer 110 of Embodiment 8 is similar to that of Embodiment 4. In Embodiment 8, the pitch Q of the diamond-shaped structural units 214A of the diamond mirror layer 214 is 50 μm, and the height H (or the engraving depth of the roller) of the diamond-shaped structural units 214A is 25 μm-30 μm.

Comparative example

The display device of the comparative example uses a liquid crystal display (manufactured by AU Optronics Co., Ltd., model: T215HVN01.1), and the image display surface is not provided with an optical film, that is, neither a pattern layer nor a rhombohedral mirror layer is provided.

Optical measurement evaluation

Use Konica Minolta model CA-210 to measure the brightness (L255) of the bright state (255 gray scale) and the brightness (L0) of the dark state (0 gray scale) of the display device, and calculate the brightness of each gray scale (Lx, x is from 0 to 255) Contrast value (unit %): Contrast value of grayscale brightness=(Lx-L0)/(L255-L0)*100%

Table 1 shows the relationship of the gray scale corresponding to the contrast value (unit: %) when the display device is at the front viewing angle (the measuring angle is 0 degrees). It can be seen from the results in Table 1 that there is no significant difference in the contrast values of Examples 1 to 8 and the comparative example at the front view angle.

Table 2 shows the relationship between the corresponding contrast values (unit: %) of each gray scale when the measurement angle of the display device is 60 degrees (side viewing angle). Subtracting the comparison value of Table 2 from the comparison value of each gray scale of the comparative example in Table 1 at the front viewing angle, it can be found that Example 1 and Example 5 compare the comparison value of each gray scale corresponding to the comparison example in Table 1 at the front viewing angle. difference The difference is small, which means that the display device using the optical film of Example 1 and Example 5 has better contrast improvement. In particular, the difference of Example 5 is the smallest, which indicates that the display device of the optical film of Example 5 has the best contrast improvement. There is no gray-scale inversion in the first to the eighth embodiment.

Table 3 shows the relationship between the contrast value (unit: %) of each gray scale measured at 45 degrees (large viewing angle in dark state) after the measurement angle of the display device is changed from 60 degrees to 45 degrees. Subtracting the comparison value of Table 3 from the comparison value of each gray scale of the comparative example in Table 1 at the front viewing angle, it can be found that Example 1 to Example 8 in Table 3 correspond to each gray scale at the front viewing angle of the comparative example in Table 1. The differences in the contrast values are all smaller than the corresponding differences in the comparative example in Table 3, indicating that the display devices using the optical films of Examples 1 to 8 can obtain a better degree of contrast improvement compared with the comparative example. The improvement effect of Example 5 to Example 8 is more obvious than that of Example 1 to Example 4. There is no gray-scale inversion in the first to the eighth embodiment.

Human eye evaluation of appearance taste

Observe the appearance and taste of the display device with human eyes. Among them, Example 1 and Example 5 were judged to have the best appearance grade (no Moire phenomenon); Example 3 and Example 4 were found to have straight and horizontal stripes; Example 2, Example 6, Example 7 The appearance grade level of Example 8 is between no Moire corrugation and vertical and horizontal striped corrugations.

Human eye evaluation color cast (Washout)

The color shift of the display device was observed by human eyes, and the evaluation was the best (color Example 5 had the lowest degree of deviation, followed by Example 8, Example 7, Example 6, Example 1, Example 3, and Example 2, and Example 4 had the largest color cast.

To sum up, although the present invention has been disclosed as above by embodiments, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention belongs can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be subject to those defined by the attached patent scope.

110: pattern layer

110S: surface

A: distance

B: distance

D1: First direction

D2: second direction

D3: Third party

D4: Fourth direction

F: Spacing

M: line width

U1: first stripe

U2: second stripe

Z: direction

Claims (6)

An optical film, comprising: a substrate: and a pattern layer, on the substrate, the pattern layer includes a plurality of stripes extending in different directions, and the stripes are formed by raised portions or depressions on the surface of the pattern layer Partial definition, wherein the stripes are formed by a transparent resin, the stripes include: a plurality of first stripes having a first extension direction; and a plurality of second stripes having a second extension direction, the The first extension direction is different from the second extension direction. The pattern layer includes a first pattern area and a plurality of second pattern areas. The first pattern area has the first stripes, and each of the second pattern areas There are the second stripes, and the second pattern areas are on opposite sides of the first pattern area. According to the optical film described in claim 1, wherein the first stripes of the first pattern area are arranged separately from each other in a direction substantially perpendicular to the first extension direction, and the second pattern areas The second stripes each have are arranged separately from each other in a direction substantially perpendicular to the second extension direction. According to the optical film described in claim 2, wherein the stripes further include a plurality of third stripes, the third stripes have a third extension direction, and the third extension direction is different from the first extension And the second extension direction, the pattern layer further includes a plurality of third pattern regions, each of the third pattern regions has the third stripes, and the third pattern regions are opposite to the first pattern region Side and separated from the second pattern areas. The optical film described in item 3 of the scope of patent application, wherein the first angle defined by the intersecting point of the first extension direction and the third extension direction is 45 degrees; or the second extension direction and the second extension direction The second angle defined by the intersecting points of the three extension directions is 45 degrees. According to the optical film described in item 3 of the scope of patent application, the stripes further include a plurality of fourth stripes with a fourth extension direction which is different from the first extension direction and the first extension direction. Two extension directions and the third extension direction, the pattern layer further includes a plurality of fourth pattern regions, each of the fourth pattern regions has the fourth stripes, and the fourth pattern regions are in the first pattern region And separate from the second pattern areas and the third pattern areas. The optical film as described in item 5 of the scope of patent application, wherein the first stripes, the second stripes, the third stripes, or the fourth stripes have a line width, and the line width is 5 μm-25 μm; The adjacent first stripes, the second stripes, the third stripes, or the fourth stripes have a pitch, and the pitch is 10 μm to 40 μm.

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