TW201944136A - Optical plate, optical structure, backlight module and display device with protrusions - Google Patents

Abstract

An optical plate, an optical structure, a backlight module and a display device with protrusions are provided. The optical plate includes a main body having a first surface, and several protrusions formed on and projected from the first surface of the main body. An area ratio of the protrusions to the first surface is 0.03%~35%. A pitch of the protrusions is in a range of 0.5 mm to 10 mm, and a portion of the first surface outside the protrusions has a mean roughness Ra in a range of 0.01 [mu]m to 0.1 [mu]m.

Description

Optical plate with protruding portion, optical structure, backlight module and display device

The present invention relates to an optical plate with an optical plate, an optical structure, a backlight module, and a display device, and more particularly to an optical plate with a protruding portion that can be used as a diffuser plate, an optical structure, a backlight module, and a display device.

A diffusion plate is an optical plate used in electronic products such as display devices. Its main function is to diffuse and atomize the light from the light source, so that the screen of the product exhibits uniform brightness and quality. Different electronic products have different requirements for the screen image quality. Therefore, when a diffuser plate manufacturer manufactures a diffuser plate, it will manufacture diffuser plates with different light penetrations according to the needs of downstream manufacturers. Taking a side-type backlight module applied to a display device (such as a liquid crystal display device) as an example, it generally includes a light guide plate formed of a light-transmitting material, and a light source (such as a cold cathode tube) provided at the side end of the light guide plate. (Line light source), a light reflection film located under the light guide plate and the line light source, and a diffusion plate and / or a lens film disposed on the light guide plate to form a light emitting surface.

In order to improve brightness and reduce power consumption, in recent years, in color liquid crystal display devices, one or two lens films having a 稜鏡 -shaped surface are particularly arranged on the upper surface of the diffuser plate or between the diffuser plate and the light guide plate. The light emitted from the light guide plate is efficiently focused in the front direction of the liquid crystal panel. In addition, in order to improve the uneven amount of light caused by the distance from the light source, there is also a technique in which a dot-like pattern formed by light diffusion ink is formed on the light guide plate and becomes larger as it moves away from the light source. The main purpose is to uniformly diffuse the light and prevent the dot pattern printed on the light guide plate from being seen. In the past, the production of these lens films was achieved by embossing of a thermoplastic resin plate or transfer of the shape of a cymbal using a radiation-hardening resin. However, these existing lens films are high in manufacturing cost and are considered to be the main reason for the high price of the backlight module. In addition, the existing lens films are also limited in their material selection range due to their limited manufacturing methods. In addition, the lens film also has to be used in combination with the light diffusing film because it does not have a light diffusing effect, resulting in a complicated assembly step of the backlight module.

In addition, various functional films such as diffusion films, lens films, and brightness enhancement films that may be used in addition to the above-mentioned diffusion plates in display devices are used to increase the brightness of the display screen and reduce the uneven brightness of the entire screen. For the purpose of thinning and reducing the display device and reducing the cost, there are also many studies focusing on the development of an optical plate that integrates multiple functions, such as the integration of the light diffusion effect of a diffuser plate and the light collection effect of a brightness enhancement film into an optical plate. In particular, as display devices (such as liquid crystal televisions) have recently progressed from small to large, it is more desirable to develop an optical diffusion plate that can reduce the number of functional films used but can improve brightness and diffusion performance.

The invention relates to an optical plate, an optical structure, a backlight module, and a display device. The protrusions have a specially designed protrusion, which can improve the uniformity of luminance when used as a diffusion plate. ).

According to the present invention, an optical plate is provided, comprising: a body having a first surface; and a plurality of protrusions located on the first surface and protruding from the first surface. The proportion of the protrusions on the first surface is: 0.03% ~ 35%, there is a pitch between the protrusions of 0.5mm ~ 10mm, and the part of the first surface outside the protrusions has a first centerline average roughness Ra of 0.01µm ~ 0.1 µm.

The present invention provides an optical structure including the optical plate of the foregoing embodiment, an optical film disposed above the first surface of the body, and a colloidal layer disposed between the optical plate and the optical film, wherein the colloidal layer is bonded to the protrusions. An air layer is formed between the first surface and the colloidal layer.

The present invention provides an optical structure including the optical plate, an optical film, and a colloid layer of the foregoing embodiment. The optical plate includes a body and a plurality of protruding portions. The body has a first surface. The protrusions protrude from the first surface. One of the protrusions has an outer diameter of 200 µm ~ 500 µm and a maximum height of 10 µm ~ 35 µm. A distance between two adjacent protrusions is 0.5 mm ~ 10mm. The optical film is disposed above the first surface of the body. The colloid layer is disposed between the optical plate and the optical film. The colloid layer adheres to the top surface of the protrusion, and an air layer is provided between the first surface and the colloid layer.

The present invention provides a backlight module including a light source and the optical plate of the foregoing embodiment or the optical structure of the foregoing embodiment corresponding to the light source.

The present invention provides a display device including the optical plate of the foregoing embodiment or the backlight module of the foregoing embodiment, wherein the display device is selected from the group consisting of a television, a notebook personal computer, a mobile computer, and a computer. A group of monitors.

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

An embodiment of the present invention proposes an optical plate, which can be applied to a display device as a diffuser plate of a backlight module. The optical plate of the embodiment uses a protrusion formed on the surface of the main body and a design to reduce the surface roughness to improve the uniformity of luminance (e.g., the uniformity of the four corners) of the light emitting area of the display device. Therefore, according to the embodiment, a diffusion plate with high diffusion performance can be provided, which reduces the number of other functional films traditionally used, thereby reducing costs and making application display devices lighter and thinner (especially large-sized display devices). When the optical plate of the embodiment is used as a diffuser, the surface of the main body (eg, the first surface) with the protruding portion can be directed toward the light source of the backlight module, and one of the rough back surfaces (eg, the second surface) of the main body can be directed toward the backlight Light source of the module.

The embodiments are described in detail below with reference to the drawings. It should be noted that the structures and contents provided in the embodiments are only for illustrative purposes, and the scope of the present invention is not limited to these aspects. The same or similar reference numerals in the embodiments are used to indicate the same or similar parts. It should be noted that the present invention does not show all possible embodiments. Changes and modifications can be made to the structure without departing from the spirit and scope of the invention to meet the needs of practical applications. Therefore, other implementations not proposed in the present invention may also be applicable. Moreover, the drawings have been simplified to clearly explain the content of the embodiments, and the dimensional proportions on the drawings are not drawn according to the actual products. Therefore, the contents of the description and the drawings are only used to describe the embodiments, but not to limit the scope of protection of the present invention.

In addition, the ordinal numbers used in the description and the request items, such as "first", "second", "third", etc., are used to modify the elements of the request, and they do not themselves imply and represent the request elements. Any previous ordinal number does not represent the order of one request element and another request element, or the order of manufacturing methods. The use of these ordinal numbers is only used to enable a request element with a certain name to have another The same named request element makes a clear distinction. Furthermore, the description relates to terms that may be used in the request, such as "beneath", "below", "lower", "above", " "Upper" or similar words are used to facilitate the description and reference to the spatial relationship between one element or feature and another element or feature as drawn in the illustration. Therefore, those with ordinary knowledge can know that in addition to the orientation of the components shown in the figure, these spatially related terms also include the orientation of the components that are different from those shown in use or operation. Therefore, the terms used in the description and the claims are only used to describe the embodiments, but not used to limit the protection scope of the present invention.

FIG. 1 is a partial schematic diagram of an optical plate according to an embodiment of the present invention. FIG. 2A is a schematic cross-sectional view of a protruding portion shown along a section line 2-2 in FIG. 1. FIG. 2B is a schematic view of a single protruding portion 20 of FIG. 1. Please refer to Figure 1 and Figure 2A at the same time. The optical plate 1 of an embodiment includes a main body 10 and a plurality of protrusions 20 located on the first surface 101 of the main body 10 and protruding from the first surface 101. Among them, there is a pitch Dp between 0.5 mm and 10 mm between the protrusions 20. Within this range, the optical plate can maintain a high brightness performance and can be avoided due to friction during transportation or assembly. As a result, the first surface 101 is scratched. In one example, a distance Dp between the protrusions 20 is 0.5 mm to 9 mm; in another example, Dp is 0.5 mm to 8 mm. The portion of the first surface 101 other than the protruding portion 20 is a smooth surface. In one example, the portion of the first surface 101 outside the protrusion 20 has a first centerline mean roughness Ra. The Ra value is, for example, 0.01 μm to 0.1 μm. When the Ra value is 0.01 μm to At 0.1µm, the four corners of the diffuser can be evenly aligned. In one example, the first centerline average roughness Ra of the first surface 101 is, for example, not more than about 0.08 μm, that is, about 0.08 μm or less than 0.08 μm. In another example, the ten-point mean roughness Rz of the first surface 101 ranges from 0.1 μm to 1 μm, for example, 0.5 μm to 1 μm. In one example, the body 10 and the protruding portion 20 are integrally formed, for example.

In one embodiment, the protrusion 20 has a maximum height Hp between the apex P of the protrusion and the first surface, and the range of the maximum height Hp is between 10µm and 35µm, for example, between 12µm and 30µm, or It is in the range of 15µm ~ 27µm. In one example, the maximum height Hp (without limitation) of the protrusion 20 is approximately 19.32 μm; in another example, the maximum height Hp (without limitation) of the protrusion 20 is approximately 16.46 μm. Furthermore, taking a single protrusion 20 as an example, the outer diameter Dm of the protrusion 20 is defined as a maximum diameter of the bottom surface of the protrusion 20 that is in contact with the first surface 101 of the body 10. The distance Dp between the protrusions 20 is defined as the sum of the outer diameter Dm of one of the protrusions and the shortest distance Ds between two adjacent protrusions 20, that is, Dp is the sum of Dm and Ds. In an embodiment, the bottom surface of the protruding portion 20 in contact with the first surface 101 is substantially circular, and the outer diameter Dm thereof ranges from 200 µm to 500 µm, for example, 250 µ to 450 µm, or 270 µm to 400 µm. In one example, the outer diameter of the protrusion 20 (without limitation) is about 310.51 μm.

In one embodiment, the ratio Hp / Dm of the maximum height Hp of the protruding portion 20 to the outer diameter Dm ranges from 0.01 to 0.2, for example, from 0.01 to 0.18, or from 0.02 to 0.175. In one example, the ratio of Hp / Dm of the protrusion 20 (non-limitingly) is about 0.062; in another example, the ratio of Hp / Dm of the protrusion 20 (non-limitingly) is about 0.053.

In addition, in the embodiment, the surface of a protrusion 20 forms an inclination angle α with the first surface 101 of the body 10. As shown in FIG. 2A, an inclination angle α is formed between the outermost edge of the bottom of the protrusion 20 and the apex P of the protrusion, which is in the range of 2 to 10 degrees, for example, 2.5 to 9 degrees, or It is 3 degrees to 7.5 degrees. In one example, the inclination angle (without limitation) of the protrusion 20 is about 5.2 degrees.

In one embodiment, the protruding surface 201 of the protruding portion 20 has a curved surface. As shown in FIG. 1, the protruding portion 20 is a bump, and its shape may be a part of a sphere. Therefore, in an embodiment, the projection of the protrusion 20 on the first surface 101 is circular, and the protrusion 20 has a curved surface with a curvature radius between 300µm and 1000µm, for example, 400µm to 900µm, or 450µm to 850µm. . In one example, one of the protrusions 20 has a radius of curvature (without limitation) of about 640 μm.

As shown in FIG. 2B, the projection 20 of this embodiment is a part of a sphere, and the projection of the projection 20 on the first surface 101 (not shown in FIG. 2B) is circular. The protruding surface 201 includes a curved surface. The top end of the curved surface is the apex of the protruding portion P, and the inclination angle α is the angle between the protruding portion apex P and the first surface 101, such as an acute angle. However, the embodiment of the present invention does not limit the protruding portion 20 to be a part of a sphere, and it may have other types of geometrical forms, which are further illustrated below with reference to FIGS. 3A to 7B.

In FIGS. 3A to 3D, other examples in which the protruding surface 201 is a curved surface are drawn. Please refer to FIGS. 3A to 3B. The projection of the protrusion 20 on the first surface 101 (not shown in FIGS. 3A to 3B) is arc-shaped. The protrusion surface 201 includes a curved surface and an inclined surface, and the curved surface and the inclined surface are connected. And the highest point where the two meet is the apex P of the protrusion, and the inclination angle α is the angle between the inclined surface and the first surface 101, such as the acute angle between the two. Please refer to FIGS. 3C to 3D, which shows an example where the protruding surface 201 is a curved surface. In FIG. 3C, the protruding surface 201 includes two curved surfaces. The angle between the apex P of the protrusion and the first surface 101. Figure 3D shows an example that includes two inclined surfaces in addition to the two curved surfaces. For example, the 3D image includes a total of three surfaces, and the inclination angle α in the 3D image is an angle between the inclined surface and the first surface 101.

In one embodiment, the protrusion 20 includes a curved surface, and the inclination angle α is an included angle between the apex P of the protrusion and the first surface 101. In another embodiment, the protrusion 20 includes an inclined surface, and the inclination angle α is an inclined surface and the first surface 101. Angle.

In an embodiment, as shown in FIGS. 4A to 4C, the protruding portion 20 is a tapered bump, and the vertex P of the protruding portion is located at the tapered sharp point. Please refer to FIG. 4A first, the projection of the protruding portion 20 on the first surface 101 is circular, and the protruding surface 201 has a curved surface. Please refer to FIG. 4B and FIG. 4C. The projection of the protrusion 20 on the first surface 101 may be a polygon, such as a quadrilateral as shown in FIG. 4B, such as a square or a rectangle, or a triangle as shown in FIG. 4C. As shown in FIGS. 4B to 4C, in one embodiment, the protruding surface 201 is composed of a plurality of inclined surfaces, and has a pyramid or triangular tower shape. In another embodiment, the protruding surface 201 may be composed of multiple curved surfaces, and the inclination angle α is formed between the vertex P of the protruding portion and the first surface 101.

In an embodiment, the projection of the protruding portion 20 on the first surface 101 of the body 10, that is, the bottom surface of the protruding portion 20 that the protruding portion 20 contacts the first surface 101 of the body 10 has a regular shape, for example, FIGS. 4A to 4C. The circle, square, triangle, or other polygon shown, the ratio of the area of the regular shape to the square of the perimeter (that is, area / perimeter ² ) is 0.03 ~ 0.08, for example, 0.039 (triangle) ~ 0.0796 (circle) shape).

In an embodiment, please refer to FIGS. 5A to 5C. The protruding portion 20 is a protruding platform, which may include a top surface 20u, the top surface 20u is a plane, and the vertex P of the protruding portion is any point of the top surface 20u.

In one embodiment, the protruding portion 20 includes a recessed portion 20R. The recessed portion 20R is formed at a center position of the protruding portion 20, that is, it can be regarded as being formed by being recessed downward from the top of the protruding portion 20. The bottom of the recessed portion 20R is a recessed point 20R1 or a flat surface 20R2. Therefore, the vertex P is formed around the recessed portion 20R, that is, the recessed portion 20R is formed between at least two vertices P. As shown in FIGS. 6A to 6B, the protruding portion 20 has a concave point 20R1 between two vertexes P, and the distance between the vertex P and the concave point 20R1 is the recessed depth H _D of the protruding portion 20. In one embodiment, the ratio of the protrusion 20 is recessed a depth _D and a maximum H height Hp is _{((H D / Hp) ⨯100} %) may be 15% to 100% range, for example, 30% to 100%, or It is 50% ~ 90%. As shown in FIG. 6C, the bottom of the recessed portion 20R is a plane 20R2, and there may be a plurality of vertices P around the recessed portion 20R. In this embodiment, the plurality of vertices P are arranged in a circle. In an embodiment, as shown in FIG. 6C, the plane 20R2 is protruded from the first surface 101 (not shown in FIG. 6C) of the body 10. In another embodiment, the plane 20R2 may be coplanar with the first surface 101. As shown in FIG. 6D, it is a cross-sectional view taken along line 6D-6D 'in FIG. 6C. In this embodiment, the protruding surface 201 is a curved surface, and the vertex P of the protruding portion falls on the highest point of the curved surface. The protruding portion of the ring structure has A plurality of protrusion apexes P are arranged in a ring structure, and the plane 20R2 protrudes from the first surface 101 of the body 10. As shown in FIG. 6E, it illustrates another schematic view of the cross-sectional view of FIG. 6C along 6D-6D '. The difference from FIG. 6D is that the protruding surface 201 of FIG. 6E is an inclined surface. In an embodiment, the recessed portion 20R may be connected to the first surface 101 (drawn in dashed lines in FIG. 6D). At this time, the protruding portion 20 forms a ring structure, that is, the plane 20R2 of the recessed portion 20R is in common with the first surface 101. flat, concave depth H _D with the same maximum height Hp of both. Please refer to FIG. 6F to FIG. 6H, which are schematic diagrams where the recessed portion 20R is in contact with or coplanar with the first surface 101 (not shown in FIGS. 6F to 6H). In one embodiment, as shown in FIG. 6F The protruding portion 20 shown in FIG. 6G has a circular ring shape. In another embodiment, the protruding portion 20 may have a polygonal ring shape, such as a four-corner ring shape shown in FIG. 6H. Please refer to FIG. 6I, which is a cross-sectional view taken along line 6I-6I 'in FIG. 6F. In this embodiment, the protruding surface 201 is a curved surface, the protruding point vertex P is the highest point of the curved surface, and the protruding portion 20 of the ring structure has a plurality of The apexes P of the protrusions are arranged in a ring structure. Please refer to FIG. 6J again, showing another schematic view of the sectional view taken along the line 6I-6I ′ in FIG. 6F. The difference from FIG. 6I is that the protruding surface 201 in FIG. 6J is an inclined surface. Please refer to FIG. 6K, which shows a schematic view taken along the 6K-6K ′ cross-section of FIG. 6G. In this embodiment, the pit 20R1 of the recessed portion 20R is in contact with the first surface 101.

In one embodiment, the protruding portion 20 may have a stepped "convex" structure, as shown in Figs. 7A and 7B, which may be integrally formed or formed by stacking two structures having different sizes through stacking, For example, it is a structure in which FIGS. 5A to 5C and FIG. 2B with different sizes are stacked.

In one embodiment, the protruding surface 201 of the protruding portion 20 is a smooth surface, such as a smooth curved surface. Of course, the size, inclination angle, and curvature radius of the above-mentioned protruding portion 20 can be changed and adjusted according to the requirements and design of the actual application, and are not limited to the above-mentioned values. Therefore, the present invention does not limit this. In an example, the sizes, inclination angles, and curvature radii of each protrusion 20 are substantially the same and have a regular shape; of course, it may be slightly different due to process variations, as long as it is within the scope of the present invention. All are features of the present invention.

In addition, the thickness of the optical plate 1 is the thickness Hm of the main body 10 plus the height Hp of the protrusion 20. When the optical plate 1 of the present invention is used as a diffusion plate for a backlight module, the thickness of the optical plate 1 is 0.5 mm ~ It is better at 6mm. Thickness exceeding 6mm may be unsuitable for today's thin and light display devices due to excessive thickness and weight. When the thickness is thinner than 0.5mm, it may affect the diffusion effect during application due to insufficient rigidity. In one embodiment, the thickness of the optical plate 1 ranges from 0.6 mm to 5 mm (600 μm to 5000 μm); in another embodiment, the thickness of the optical plate 1 is 0.8 mm to 3 mm. In another embodiment, the thickness of the optical plate 1 is 0.8 mm to 2.5 mm. Since the height Hp of the protrusion 20 is relatively small compared to the thickness Hm of the body 10, the thickness of the optical plate 1 (ie, the thickness Hm of the body plus the height Hp of the protrusion 20) can be regarded as being approximately equal to or equal to the thickness Hm of the body 10.

FIG. 8 is a schematic diagram of a plurality of protrusions distributed on a main body of an optical plate according to an embodiment of the present invention. In one embodiment, the plurality of protrusions 20 may be evenly (regularly) arranged and distributed on the first surface 101 of the body 10. As shown in FIG. 8, the protrusions 20 located in the upper and lower rows are arranged in an offset manner. In this example, as shown in the figure, the enlarged part can be regarded as a repeating unit of the protrusions 20, and a repeating unit includes 1/4 protrusions 20-1, 20-2, 20 located at four corners. -3, 20-4, and one protrusion 20-5 located in the center, and a total of two protrusions 20 are added up. The arrangement of the protrusions in this single repeating unit is similar to the face-centered cubic arrangement in the crystal lattice. In one embodiment, the ratio of the regularly arranged protrusions to all the protrusions is 90% or more, for example, 95% or more, that is, the repeating ratio of the repeating unit is as high as 90% or more.

In one embodiment, the proportion of the protruding portion 20 relative to the first surface 101 of the body 10 is 0.03% to 35%, for example, 0.07% to 32%. In one example, the proportion of one of the protrusions 20 (without limitation) is about 0.30%. In another example, the proportion (non-limiting) of one of the protrusions 20 is about 1.21%. In another example, the proportion of one of the protrusions 20 (without limitation) is about 4.83%. The proportion of the protrusions 20 relative to the first surface 101 of the body 10 can be calculated through the distribution shown in FIG. 8. For example, the proportion of the protrusions (the proportion of the protrusions 20 can also be referred to as the distribution density of the protrusions) can be calculated based on the area occupied by the two protrusions 20 divided by the area of one repeating unit.

Taking the outer diameter Dm of a single protrusion as 310µm (radius approximately 155µm) and the distance Dp between the protrusions 20 as 5000µm (ie 5mm) as an example, the area of a repeating unit = 2 × 5000 ² . Area π × 155 ² = 75477µm ² and the proportion of the protrusions is:
(2 × 75477) ÷ (2 × 5000 ² ) = 0.30%.

Taking the outer diameter Dm of a single protrusion as 310µm (radius approximately 155µm) and the distance Dp between the protrusions 20 as 2500µm (ie 2.5mm) as an example, the area of a repeating unit = 2 × 2500 ² and the protrusion The proportion of the ministry is:
(2 × 75477) ÷ (2 × 2500 ² ) = 1.21%.

Taking the outer diameter Dm of a single protrusion as 310µm (radius approximately 155µm) and the distance Dp between the protrusions 20 as 1250µm (ie 1.25mm) as an example, the area of a repeating unit = 2 × 2500 ² and the protrusion The proportion of the ministry is:
(2 × 75477) ÷ (2 × 1250 ² ) = 4.83%.

In one embodiment, the proportion of the first surface 101 other than the protruding portion 20 is 65% to 99.97%, for example, 68% to 99.93%.

Compared with the microstructure of the existing diffuser plate, the embodiment of the present embodiment has a larger size of the protrusions 20, for example, the outer diameter Dm (the largest characteristic dimension of the bottom surface, such as the diameter) of the single protrusion 20 ranges from 200 µm to 500 µm. And the pitch reaches 0.5mm (= 500µm) to 10mm (= 10000µm); and the single microstructure of the existing diffuser plate is, for example, several µm to 30µm, and the pitch is only a few µm to 300µm or less. Therefore, compared with the existing micro-structures, the size and distribution of the micro-structures are smaller, the protrusions 20 of the optical plate of the embodiment are larger in size and more loosely distributed. With such large-sized and loosely distributed protrusions 20 and controlling the roughness of the first surface 101, the light reflectance can be increased, and the uniformity of brightness can be improved. In addition, under this design, even if the protrusions 20 are arranged regularly as shown in Fig. 1, when the optical plate of the embodiment is used as a diffuser plate of a backlight module, moire interference can be reduced or even avoided. Generation of streaks.

Furthermore, according to the embodiment of the present invention, the upper and lower surfaces of the body 10 of the optical plate 1 have different roughnesses. In one embodiment, the first surface 101 of the body 10 is a smooth surface, and a second surface 102 of the body 10 opposite to the first surface 101 may be a rough surface. That is, the second surface roughness of the second surface 102 is greater than the first surface roughness of the portion of the first surface 101 outside the protrusion 20. In one example, the average roughness of the second centerline Ra is, for example, 3 μm to 7 μm. In an example, the ten-point average roughness Rz of the second surface 102 is, for example, 20 μm to 35 μm. When applied to a backlight module, the first surface 101 can be a light incident surface and the second surface 102 can be a light emitting surface; the second surface 102 can also be made a light incident surface and the first surface 101 can be a light emitting surface.

In addition, in the embodiment, the optical plate 1 is made of, for example, a light-transmitting material, for example, it is composed of a light-transmitting resin, and a plurality of diffusion particles are added to be dispersed therein. Translucent resins that can be used include polycarbonate, polystyrene (PS), polymethyl methacrylate (PMMA), methyl methacrylate-styrene (MS), acrylonitrile-styrene ( AS), cyclic polyolefin (cyclo-olefin copolymer), polyolefin copolymer (such as poly-4-methyl-1-pentene), polyethylene terephthalate, polyester, poly Ethylene, polypropylene, polyvinyl chloride, ionomer, and the like. Among them, polycarbonate, polystyrene, polymethyl methacrylate, and methyl methacrylate-styrene are preferred. Therefore, in one embodiment, after the optical plate is manufactured, the body of the optical plate and the plurality of protrusions formed may further include a plurality of diffusing particles (such as transparent fine particles) dispersed therein for use as a light diffusing agent.

In one embodiment, the translucent resin that can be used is a resin having a flexural modulus greater than 1 GPa, such as a resin having a flexural modulus greater than 2 GPa. This type of resin can produce a relatively large amount of resin under the action of external forces. Small deformation, that is, having better supportability, makes the optical plate 1 more suitable for the application of the backlight module, that is, it has good supportability without excessively increasing the thickness of the optical plate 1.

In one embodiment, the average molecular weight of the light-transmitting resin ranges from 150,000 to 450,000. Within this range, the light-transmitting resin can have both good mechanical properties and processability. In another embodiment, the control The softening point temperature (50 ° C / hr, 1kg) of the translucent resin can also make the translucent resin have good processability between 95 ° C and 150 ° C.

In one embodiment, the total content of methanol-soluble components in the translucent resin, that is, oligomers, additives, residual monomers, and other components that can be dissolved in methanol can be 1.5% by weight or less. In this way, light transmission can be ensured. Heat resistance of the resin.

In one embodiment, the transparent diffusion particles are, for example, inorganic fine particles represented by silicon dioxide and titanium dioxide, organic fine particles such as polystyrene resin, (meth) acrylic resin, and silicon resin, and organic fine particles are preferred, for example, Use organic fine particles alone, or use a mixture of organic fine particles and inorganic fine particles. Organic microparticles are more preferably bridged organic microparticles. During the manufacturing process, at least some of the bridges are bridged, so that no deformation occurs during the processing of the translucent resin, and the state of the microparticles can be maintained. That is, fine particles that do not melt in the light-transmitting resin even when heated to the molding temperature of the light-transmitting resin are more preferable, and are more preferably organic fine particles of bridged (meth) acrylic resin and silicone resin. In one embodiment, particularly suitable transparent microparticles (diffuse particles) include, for example, polymer microparticles of poly (butyl acrylate) core / poly (methyl methacrylate) based on partially bridged methyl methacrylate. A polymer of a shell, a core / housing type polymer having a core and a shell containing a rubber-like vinyl polymer [manufactured by Rohm and Hass Campany, trade name Paraloid EXL-5136], having a bridged siloxane Silicone resin [made by Toshiba Silicone Co., Ltd., trade name Tospearl 120].

In one embodiment, the average particle diameter of the diffusion particles is 0.01 μm to 30 μm. In another embodiment, the average particle diameter of the diffusion particles added to the optical plate 1 is 0.01 μm to 20 μm. In another embodiment, the average particle diameter of the diffusion particles added to the optical plate 1 is 0.01 μm to 15 μm. It is preferable that the average particle diameter of the diffusion particles does not protrude from the surface of the main body 10 / projection 20. In one embodiment, inorganic fine particles and organic fine particles can be mixed together, for example, titanium dioxide fine particles having a particle diameter of 0.01 μm to 0.05 μm and silicon resin having a particle diameter of 1 μm to 10 μm can be mixed. In one embodiment, the light transmittance of the optical plate 1 is 45% to 70%, preferably 50% to 65%. When the light transmittance of the optical plate 1 is 45% ~ 70%, it can maintain high luminance performance at the same time and avoid the problem of seeing the light source because the light transmittance is too high.

In addition, the average particle diameter of the transparent fine particles as the diffusion particles is a weight average particle diameter measured by a particle counting method, and the number of particles of Nikkei Co., Ltd. can be used. The particle size distribution analyzer MODEL Zm was used as a measuring device. When the weight-average particle diameter is 0.01 µm ~ 30 µm, sufficient light diffusivity can be obtained and the luminous mask has excellent luminosity. The amount of addition can be effectively controlled, and the light diffusivity and light transmittance are better.

In addition, the used amount of the transparent fine particles is 0.1 to 20 parts by weight based on 100 parts by weight of the light-transmitting resin, and is particularly preferably 0.35 to 12.5 parts by weight. In one embodiment, for example, 0.05 to 1 part by weight of titanium dioxide fine particles and 0.3 to 11.5 parts by weight of silicone resin are added. When the amount of the transparent fine particles is less than 0.1 part by weight, there is a problem of insufficient light diffusibility, that is, the light source can be penetrated and seen. On the other hand, when the amount of the transparent fine particles used exceeds 20 parts by weight, the light transmittance is lowered and the brightness is deteriorated.

In one embodiment, the optical plate 1 can be made of polystyrene (PS) (for example: Taiwan Chi Mei GPPS PG-383D, which has a weight average molecular weight of about 300,000 and a softening point temperature of 106 ° C) and is transparent. Micro particles (for example: adding 0.05 ~ 1 parts by weight of titanium dioxide fine particles with an average particle size of 0.01µm ~ 0.055µm and 0.3 ~ 11.5 parts by weight of silicone resin with an average particle size of 1µm ~ 10µm), this combination can be ordered by any method or device The layer is produced to form a substrate (ie light diffusion plate). In the embodiment, a plate-like structure having a predetermined thickness is formed by, for example, a melt extrusion method. In the case of melt extrusion, it is best to reduce the pressure in the melting zone of the extruder to 1.33-66.5 kPa and extrude. If the melting zone of the extruder is not decompressed, the matched transparent particles, especially the insoluble acrylic polymer particles, will be affected by oxygen, which may cause the particle surface to partially collapse and reduce the light diffusion performance. In addition, other methods known in the past can also be used. For example, injection molding, injection compression molding, blow molding, compression molding, and powder molding can be used to complete the molding of the optical plate 1 of the embodiment.

In addition, in addition to making a single-layer board, the optical board 1 of the present invention may also be a multi-layer board. For example, in addition to the above-mentioned light-transmitting resin layer, a coating layer may be included. In one embodiment, the thickness of the coating layer is 0.01 mm to 0.5 mm, or 0.02 mm to 0.4 mm, or 0.03 to 0.3 mm. If the thickness of the coating layer exceeds 0.5 mm, there may be a problem that the thickness of the backlight module unit may not be sufficient to meet the requirements for thinning the liquid crystal display device. In addition, this coating layer has, for example, high transparency that can fully exert the lens effect, and the resin that can be used is an acrylic resin such as polymethyl methacrylate, methyl methacrylate-styrene, acrylonitrile-styrene, etc. . Among them, polymethyl methacrylate and methyl methacrylate-styrene are more preferable.

In addition, the composition of the optical plate 1 may further include the addition of an ultraviolet absorber to improve the weatherability of the optical plate 1 and block harmful ultraviolet rays; and / or may include the addition of a fluorescent agent, which can absorb light. The ultraviolet portion of the light is radiated to the visible portion.

In an embodiment in which the optical plate 1 is a multilayer board, 100 parts by weight of the acrylic resin forming the above-mentioned coating layer contains 0.5 to 15 parts by weight of an ultraviolet absorber, and a diffusion having an average particle diameter of 0.01 μm to 30 μm may be added as required. The particles are, for example, 0.1 to 20 parts by weight of transparent fine particles and 0.001 to 0.1 parts by weight of a fluorescent agent.

In one embodiment, the ultraviolet absorber is, for example, a benzophenone-based ultraviolet absorbent of 2,2'-dihydroxy-4-methoxybenzophenone, 2- (4,6-diphenyl-1, 3,5-triazine-2-substituent) -5-hexylhydroxyphenol triazine-based ultraviolet absorber, 2- (2H-benzotriazole-2-substituent) -4-methylphenol, 2- (2H-benzotriazole-2-substituent) -4-third octylphenol, 2- (2H-benzotriazole-2-substituent) -4,6-bis (1-methyl-1 -Phenyl) phenol, 2- (2H-benzotriazole-2-substituent) -4,6-bis-tertiaryamylphenol, 2- (5-chloro-2H-benzotriazole- 2-Substituent) -4-methyl-6-tert-butylphenol, 2- (5-chloro-2H-benzotriazole-2-substituent) -2,4-tert-butylphenol and 2,2'-Methylenebis [6- (2H-benzotriazole-2-substituent) -4- (1,1,3,3-tetramethylbutyl) phenol] and other benzotris An azole-based ultraviolet absorber.

In one embodiment, preferred ultraviolet absorbers are, for example, 2- (2-hydroxy-5-tolyl) benzotriazole, 2- (2-hydroxy-5-third-octylphenyl) benzotriazole, 2- (2-hydroxy-3,5-dicumene) phenylbenzotriazole, 2- (2-hydroxy-3-tertiarybutyl-5-tolyl) -5-chlorobenzotriazine Azole, 2,2'-methylenebis [4- (1,1,3,3tetramethylbutyl) -6- (2H-benzotriazole-2-substituent) phenol], 2- [ 2-hydroxy-3- (3,4,5,6-tetrahydro-o-phthalimidomethyl) -5-tolyl] benzotriazole. Among them, 2- (2-hydroxy-5-tertiary octylphenyl) benzotriazole (Ciba-Geigy, trade name Tinuvin 329), 2,2'-methylenebis [4- (1, 1,3,3-tetramethylbutyl) -6- (2H-benzotriazole-2-substituent) phenol] is preferred.

In addition, when an ultraviolet absorbent is used in the examples, one component may be selected singly or two or more components may be used in combination, and it is preferable to use 0.5 to 15 parts by weight relative to 100 parts by weight of the acrylic resin, and 1 to 10 parts by weight. Serve better. When the amount used is less than 0.5 parts by weight, the weather resistance is not good and the hue change is large. When the amount used is more than 15 parts by weight, the hue and brightness are deteriorated.

In addition, the fluorescent agent used in the examples (having the energy of the ultraviolet part capable of absorbing light and radiating the energy to the visible part) is within a range that does not impair the light resistance, and is used to mix synthetic resins, etc. Those whose color tone is improved to white or blue-white, for example, stilbene-based, benzimidazole-based, benzoxazole-based, xylylenediimide-based, rose red-based, coumarin-based, oxazole-based compounds, and the like. In one embodiment, the amount of the fluorescent agent used is, for example, a range of 0.001 to 0.1 parts by weight relative to 100 parts by weight of the acrylic resin, and a range of 0.002 to 0.08 parts by weight is preferable. By blending the fluorescer in the above range, the light-emitting surface can obtain a sufficient luminous property and the effect of improving hue.

Although one of the embodiments of the present invention is further described in conjunction with FIG. 1 and FIG. 2A, the present invention is not limited thereto. FIG. 9 is a partial schematic diagram of an optical plate according to another embodiment of the present invention. FIG. 10 is a schematic cross-sectional view of another protruding portion shown along a section line 10-10 in FIG. 9. Elements in FIGS. 9-10 that are the same as or similar to those in FIGS. 1 to 2A are denoted by the same or similar reference numerals for the sake of clear explanation. As shown in FIG. 9, the optical plate 1 ′ also includes a body 10 and a plurality of protrusions 30 located on the first surface 101 of the body 10 and protruding from the first surface 101. In this embodiment, the distance Dp, the maximum height Hp, the inclination angle α between the protrusions 30, and the roughness of the first surface 101 and the second surface 102, and other related descriptions, please refer to the foregoing content, and are not repeated here. The protruding portion 30 of this embodiment is different from the aforementioned protruding portion 20 as shown in FIGS. 1 to 2A in that a protruding portion 30 includes a bump 30B and a bottom ring 30R. The ring portion 30R is located on the bump. Below 30B. As shown in FIGS. 9 and 10, the annular portion 30R surrounds and connects the bump 30B, and forms a protruding outer edge 301 on the first surface 101. In an actual production, the ring portion 30R and the bump 30B are integrally formed with the body 10. Whether it is the protruding portion 20 as shown in FIGS. 1 to 2A or the protruding portion 30 as shown in FIGS. 9 to 10, the light emitting area of the display device can maintain high luminance and can achieve the advantage of improving uniformity of luminance. .
＜ Related experiments ＞

In the following series, several groups of related experiments and their data are used to illustrate the examples. For the structure of the optical plate 1, please refer to the above and Figs. 1-10. In the experiment, several sets of samples are proposed, and the specifications of each sample are as follows:

Comparative Example 1—A commercially available single-sided bite diffuser DS551A (Chimei Industrial) has a surface centerline average roughness Ra of 3 to 7 μm and a thickness of 1.5 mm.

Comparative Example 2-A diffuser plate has a plurality of irregular islands protruding from the surface of the substrate body. The longest platform width of the top surface of these irregular islands ranges from 0.388 to 2.315 mm, and the height is 23.02 µm. The distance between the irregular islands is 21 ~ 433µm, and the thickness is 1.5mm.

Experimental Examples 1 to 3—Optical plates as described in the above Figures 1 and 2A. Related parameter series are shown in Table 1.

Brightness, evenness of four corners:

The measurement was performed using a luminance meter model BM-7A manufactured by TOPCON CORPORATION, and the light diffusion plates of Experimental Examples 1 to 3 and Comparative Examples 1 to 2 were set to LED lamps during the measurement. Glow measurement is performed on the light box module set by the source array. Among them, the luminance value is a normalized value, that is, the central luminance measurement values of Comparative Examples 1 to 2 and Experimental Examples 1 to 3 are based on the standard product (the current commercially available diffuser plate DS601A (Chimei Industrial)) luminance measurement value. 100% normalized value. The four-corner uniformity is the average of the four values of the four corners of the module divided by the central brightness of the module.

Roughness:

A surface roughness tester (model SJ-210) from Mitutoyo was used to measure the surface roughness. The first surface roughness Ra and Rz and the second surface Ra and Rz other than the protrusions were randomly measured, and the measurement distance was 5 mm.

Outer diameter, height, inclination angle and pitch of the protrusion:

By using KEYENCE's laser conjugate focus meter (model VK-X100 Series) as a measuring instrument, random sampling and measurement are performed.

The above measurement results are recorded in Table 1. However, the values in Table 1 are only examples, and the scope of the embodiment of the present invention is not limited to the values in the table.

Table 1

It can be known from the data in Table 1 that the experimental examples 1 to 3 have the average roughness of the first centerline because of the proportion of the projections on the first surface ranging from 0.03% to 35% and the portion of the first surface other than the projections. Ra is from 0.01 µm to 0.1 µm, and its average four-corner uniformity is better than that of Comparative Examples 1 to 2. That is, the design of the protrusions in Experimental Examples 1 to 3 can make the optical plate have better uniformity performance.

In addition, from the data in Table 1, it can be seen that the optical plates of Experimental Examples 1 to 3 have the proportion of the protrusions on the first surface ranging from 0.03% to 35%, and the first surface is the first portion outside the protrusions. The centerline average roughness Ra is 0.01 µm ~ 0.1µm, and its 60-degree angle gloss values are better than those of Comparative Examples 1 ~ 2. That is, the protrusion design of Experimental Examples 1 ~ 3 can improve the reflectance of oblique rays. , So that the optical plate has better uniformity performance.

Please refer to FIG. 11A, which illustrates a schematic diagram of a backlight module using an optical plate according to an embodiment of the present invention. The backlight module 400 of this embodiment is, for example, a direct type backlight module suitable for a flat display module, and includes a diffuser plate 410, at least one light source 420 (a plurality of light sources are shown in FIG. 11A), and a frame 440. The frame defines an accommodating space 442. The diffuser plate 410 and the light source 420 are located in the accommodating space 442. The diffuser plate 410 is disposed above the light source 420. The diffusion plate 410 is, for example, an optical plate in any of the above embodiments, and includes a body 10 having a first surface 101 and a plurality of protrusions 20 located on the first surface 101 and protruding from the first surface 101. In FIG. 11A, the light source 420 is disposed opposite to the first surface 101 of the diffuser plate 410. At this time, since the average roughness Ra of the center line of the first surface 101 of the diffusion plate 410 is 0.01 μm to 0.1 μm, and its 60-degree angular gloss is greater than 90, it can effectively enter the light source 420 at a high angle (inclinedly) The light incident to the first surface 101 of the diffuser plate 410 is transmitted to the four corners of the diffuser plate 410 through reflection, that is, the diffuser plate 410 has a high uniformity of the four corners, so that the backlight module can have a uniform high brightness. degree.

In an application example, the light source 420 includes, for example, a substrate 422 and a light-emitting unit 424. The light-emitting unit 424 is, for example, a light emitting diode (LED) element or other types of light-emitting elements and is disposed on the substrate 422. The light emitted by the light emitting unit 424 enters the diffuser plate 410 and then emits light through the second surface 102 of the diffuser plate 410, thereby forming a surface light source with high uniformity of brightness.

FIG. 11B is a schematic diagram of another backlight module to which the optical plate according to an embodiment of the present invention is applied. The difference between FIG. 11B and FIG. 11A is that the rough surface (eg, the second surface 102) of the main body 10 of the optical plate in FIG. 11B is, for example, a biting surface that faces the light source 420 of the backlight module. It is one of the applications of the present invention. In this embodiment, another optical film layer or optical plate can be attached to the protruding portion through the colloid layer to improve the overall optical performance of the backlight module.

In one embodiment, the colloidal layer is, for example, a pressure-sensitive adhesive such as acrylic, polyurethane, rubber, or siloxane. FIG. 12A is a schematic diagram illustrating bonding of an optical plate and an optical film to which an embodiment of the present invention is applied. FIG. 12B is a schematic cross-sectional view of an optical plate and an optical film drawn along a section line 12B-12B of FIG. 12A. Please also refer to Figures 12A and 12B.

In an example, the optical plate 1 of the embodiment is bonded to an optical film OP with a colloid layer 71. The optical film OP is, for example, disposed above the first surface 101 of the body 10. The colloid layer 71 is disposed on the optical plate. 1 and the optical film OP, and the colloid layer 71 is bonded to the top surface of the protruding portion 20 of the optical plate 1. As shown in FIG. 12B, the colloid layer 71 has a thickness L _ad , the optical film OP has a distance L _gap from the first surface 101, and the top surface of the protrusion 20 of the optical plate 1 is trapped in the colloid layer 71 and supported. The optical film OP is held, that is, the colloidal layer 71 does not directly adhere to and contact the first surface 101. Therefore, an air layer 80 is formed between the first surface 101 of the body 10 and the colloidal layer 71. In an example, the thickness L _{ad of the} colloidal layer 71 is, for example, 3 to 7 μm, and the distance L _gap between the bottom of the optical film OP and the first surface 101 is, for example, 10 to 42 μm. Furthermore, the air layer 80 of the embodiment is uniformly formed between the optical plate 1 and the colloidal layer 71, that is, under the entire optical film OP, between the first surface 101 of the body 10 and the bottom surface of the colloidal layer 71. Maintain approximately the same height. Compared with the optical structure in which the colloidal layer 71 directly adheres and contacts the first surface 101, the presence of the air layer 80 can cause a larger angle of refraction of the light emitted from the first surface, thereby enhancing the light diffusion effect.

In one embodiment, considering the thickness of the colloid layer and the design with the presence of an air layer, the maximum height Hp of the protrusion 20 should be in the range of 10µm ~ 35µm, such as 12µm ~ 30µm, or 15µm ~ In the range of 27µm, this ensures that the air layer is evenly formed between the optical plate 1 and the colloid layer 71.

In one embodiment, when the outer diameter Dm of the protrusion is in the range of 200 µm to 500 µm and the distance between two adjacent protrusions is in the range of 0.5 mm to 10 mm, it can effectively provide the attached optical film OP. With good supporting effect, the first surface 101 and the bottom surface of the colloid layer 71 can be maintained at about the same height. In another implementation, when the proportion of the protrusion on the first surface is 0.03% to 35%, and the first centerline average roughness Ra of the portion of the first surface other than the protrusion is 0.01 μm to 0.1 μm It can provide both a good support effect for the optical film OP and a good diffusion performance with high uniformity of the four corners.

In one embodiment, the protrusion structure having the protrusion apex P is, for example, the protrusion 20 of FIG. 2B, the protrusions of FIGS. 3A to 4C, or the protrusions of FIGS. 6A to 6C and 6F to 6H. The apex P of the protruding portion may be trapped in the colloidal layer 71 to generate an anchoring effect, thereby increasing the adhesion between the colloidal layer 71 and the protruding portion.

In an embodiment, as shown in FIG. 12C, the protruding portion having the recessed portion 20R is, for example, the protruding portion of FIGS. 6A to 6C or 6F to 6H (FIG. 12C is a schematic view showing the protruding portion of FIG. 6B) ), The proportion of the air layer can be increased by adjusting the depression depth H _D (shown in FIG. 6B) of the recessed portion 20R, even if the depression depth H _D and the maximum height Hp (shown in FIG. 6B) The proportion ranges from 15% to 100%, such as 30% to 100% or 50% to 90%. When the range of the ratio of concave depth H _D and the maximum height Hp falls from 15% to 100%, OP after the optical film bonded to adhesive layer 71, the recessed portion remains some space that is not in the colloid layer 71, can use this Increase the proportion of the overall air layer and strengthen the optical diffusion effect again to improve the overall optical performance.

Moreover, the applicable optical film OP is, for example, a multilayer optical film material including one or more diffusion films and one or more prism sheets, or a microlens film and one or more Multi-layer optical film materials, such as sacral layers, to adjust the light output angle (for example, concentrated light). Although in FIGS. 12A to 12C, the optical film OP includes a diffusion film 73 and a chirped layer 74 as an example, the present invention does not specifically limit the applicable optical film and / or chirped structure and layers. Number or aspect.

The aforementioned backlight module 400 can be used as a backlight module of a display device, such as a television, a notebook personal computer, a mobile computer, a monitor for a computer, etc., or the backlight module 400 can be directly used for lighting, such as a display. Lightbox, Kanban.

In summary, the optical plate proposed in the embodiment is formed on the surface of the main body with the protruding portion having the special design as described above. When the optical plate of the embodiment (as shown in Figs. 1 and 9) is used as a diffusion plate, the brightness uniformity can be improved compared to the current diffusion plate. Therefore, using the optical plate of the embodiment as a diffusion plate can not only improve the display effect of the image, avoid the occurrence of moire interference fringes, but also reduce the number of other functional films, reduce manufacturing costs, and make the display of the application The device as a whole becomes thinner and thinner, and has extremely high application value especially for large-sized display devices. In addition, when the optical plate of the embodiment is used as a diffusion plate and its protrusions are bonded with an optical film through the colloid, the protrusions can also support the optical film to form an air layer between the surface of the optical plate body and the colloid layer. Strengthen the overall optical diffusion effect.

To sum up, although the present invention has been invented by way of example, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention pertains can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the attached patent application.

1‧‧‧ Optical Plate

10‧‧‧ Ontology

101‧‧‧ the first surface of the body

102‧‧‧Second surface of the body

20, 20-1, 20-2, 20-3, 20-4, 20-5, 30‧‧‧ protrusions

20R‧‧‧ Depression

20R1‧‧‧Dip

20R2‧‧‧Plane

20u‧‧‧Top

201‧‧‧ raised surface

30B‧‧‧ bump

30R‧‧‧Ring

Dp‧‧‧pitch

Dm‧‧‧ Outside diameter

α‧‧‧ tilt angle

H _D ‧‧‧Down Depth

Hp‧‧‧Maximum height

Ds‧‧‧The shortest distance between two adjacent protrusions

Hm‧‧‧ thickness of body

400‧‧‧ backlight module

410‧‧‧ diffuser

420‧‧‧light source

422‧‧‧ substrate

424‧‧‧Light-emitting unit

440‧‧‧Frame

442‧‧‧accommodation space

OP‧‧‧ Optical Film

71‧‧‧ colloid layer

73‧‧‧ diffuser

74‧‧‧ 稜鏡

80‧‧‧air layer

L _ad ‧‧‧thickness of colloidal layer

L _gap ‧‧‧ distance between optical film and first surface

P‧‧‧ Projection Vertex

FIG. 1 is a partial schematic diagram of an optical plate according to an embodiment of the present invention.

FIG. 2A is a schematic cross-sectional view of a protruding portion shown along a section line 2-2 in FIG. 1.

FIG. 2B is a schematic view of a single protruding portion of FIG. 1.

3A to 3D are schematic diagrams of several examples in which the protrusion surface is a curved surface.

4A to 4C are schematic diagrams showing several examples in which the protrusions are tapered bumps.

5A to 5C are schematic diagrams showing several examples in which the protrusion has a top surface.

6A to 6K are schematic diagrams showing several examples in which the protruding portion has a recessed portion.

7A to 7B are schematic diagrams of protrusions having a stepped structure.

FIG. 8 is a schematic diagram of a plurality of protrusions distributed on a main body of an optical plate according to an embodiment of the present invention.

FIG. 9 is a partial schematic diagram of an optical plate according to another embodiment of the disclosure.

FIG. 10 is a schematic cross-sectional view of another protruding portion shown along a section line 10-10 in FIG. 9.

FIG. 11A is a schematic diagram of a backlight module using an optical plate according to an embodiment of the present invention.

FIG. 11B is a schematic diagram of another backlight module to which the optical plate according to an embodiment of the present invention is applied.

FIG. 12A is a schematic diagram illustrating bonding of an optical plate and an optical film to which an embodiment of the present invention is applied.

FIG. 12B is a schematic cross-sectional view of an optical plate and an optical film drawn along a section line 12B-12B of FIG. 12A.

Fig. 12C is a schematic cross-sectional view of another embodiment of the optical film along Fig. 12B.

Claims (14)

An optical plate includes: A body having a first surface; and A plurality of protrusions are located on the first surface and protrude from the first surface, and the proportion of the protrusions on the first surface of the body is 0.03% to 35%, and two adjacent protrusions There is a pitch between 0.5 mm and 10 mm, and the portion of the first surface other than the protrusions has a first centerline average roughness Ra of 0.01 μm to 0.1 μm. The optical plate according to item 1 of the scope of patent application, wherein one of the protrusions has an outer diameter of 200 μm to 500 μm. The optical plate according to item 1 of the scope of patent application, wherein a ratio of a height / outer diameter of the protrusions ranges from 0.01 to 0.2. The optical plate according to item 1 of the patent application scope, wherein the protruding portions include a recessed portion formed between at least two vertices of the protruding portion. The optical plate according to item 1 of the patent application scope, wherein the protrusions have a curved surface with a radius of curvature between 300 μm and 1000 μm. The optical plate according to item 1 of the scope of the patent application is composed of a translucent resin, wherein the flexural modulus of the translucent resin is greater than 1 GPa. The optical plate according to item 1 of the scope of patent application, wherein one of the protrusions includes: A bump; and An annular portion is located below the bump, and the annular portion surrounds and connects the bump. According to the optical plate of claim 1, wherein the body further has a second surface opposite to the first surface, wherein the second surface has a second centerline average roughness, and the second centerline The average roughness is greater than the first centerline average roughness. The optical plate according to item 7 of the scope of patent application, wherein the average roughness Ra of the second centerline is 4 μm to 8 μm. An optical structure including: The optical plate as described in any one of claims 1 to 9 of the scope of patent application; An optical film disposed above the first surface of the body; and A colloid layer is disposed between the optical plate and the optical film. The colloid layer is adhered to the top surfaces of the protrusions, and an air layer is provided between the first surface and the colloid layer. An optical structure including: An optical plate, including: A body having a first surface; and A plurality of protrusions protrudes from the first surface. One of the protrusions has an outer diameter of 200 µm ~ 500 µm and a maximum height of 10 µm ~ 35 µm. There is a distance between two adjacent protrusions. One pitch is 0.5 mm ~ 10mm; An optical film disposed above the first surface of the body; and A colloid layer is disposed between the optical plate and the optical film. The colloid layer is bonded to the top surface of the protrusion, and an air layer is provided between the first surface and the colloid layer. The optical structure according to item 11 of the scope of patent application, wherein the protruding portions include a recessed portion, and an air layer is provided between a bottom of the recessed portion and the colloid layer. A backlight module includes: A light source; and The optical plate according to any one of claims 1 to 9 or the optical structure according to any one of claims 10 to 12 of the scope of patent application is provided corresponding to the light source. A display device includes: The optical plate according to any one of claims 1 to 9 or the optical structure according to any one of claims 10 to 12, wherein the display device is selected from the group consisting of a television, A group of laptop personal computers, mobile computers, and monitors for computers.