Surface light source module and display device

Abstract

The area light source module includes a light guide plate. The light guide plate has a first surface provided with a plurality of microstructures. Each microstructure is provided with a first structural surface and a symmetric surface, a first boundary line is arranged at the boundary of the first structural surface and the symmetric surface, the first boundary line comprises a first part line segment, and the first part line segment is provided with a first end and a second end which are opposite. A first height exists between the first end and the first surface, a second height exists between the second end and the first surface, each microstructure has the maximum depth, and the absolute value of the difference between the first height and the second height is larger than or equal to one third of the maximum depth. The distance between each position point of the first part line segment in the first direction and the corresponding position point of the partial contour of the geometric figure is less than or equal to one fifth of the semi-axis length of the first axis of the geometric figure, and the geometric figure meets the condition that the ratio of # imgabs0 # a to b is between 0.1 and 2. A display device including the area light source module is also provided. The area light source module and the display device are provided with the microstructures of the first structural surfaces, so that light emitting is uniform, and the forward light emitting effect is good.

Description

Technical Field

[0001] The utility model relates to a light source module, in particular to a surface light source module and a display device. Background Art

[0002] Reflective display devices allow users to see their display by reflecting ambient light. However, in low ambient light conditions, a front light module is often required to provide light. Conventional front light modules often utilize a light guide plate (LGP) to achieve uniform light output. For example, multiple microstructures are incorporated into the LGP's upper surface to achieve more uniform light output. However, conventional front light modules still suffer from uneven light output.

[0003] The "Background" section is intended only to facilitate understanding of the present invention. Therefore, the information disclosed in this section may contain information that is not already known to those skilled in the art. The information disclosed in this section does not imply that the information or the problems to be solved by one or more embodiments of the present invention were known or understood by those skilled in the art prior to the filing of this application. Utility Model Content

[0004] The utility model provides a light guide plate of a surface light source module provided with a plurality of microstructures, wherein each microstructure has a first structural surface, which enables the surface light source module to provide a uniform and forward illuminating light beam transmitted toward a display element.

[0005] Other purposes and advantages of the present invention can be further understood from the technical features disclosed in the present invention.

[0006] In order to achieve one or part or all of the above-mentioned purposes or other purposes, one embodiment of the present invention provides a surface light source module including a light guide plate and a light source element. The light guide plate has a first surface and a second surface relative to each other, and a light incident surface connecting the first surface and the second surface, and the first surface is provided with a plurality of microstructures. The light source element is arranged opposite to the light incident surface. Each microstructure has a first structural surface connected to the first surface, each microstructure has a symmetry plane, the symmetry plane is perpendicular to the first surface, the intersection of the first structural surface and the symmetry plane has a first intersection line, the first intersection line includes a first partial line segment, and the first partial line segment has a first end and a second end relative to each other. There is a first height between the first end and the first surface, and a second height between the second end and the first surface. Each microstructure has a maximum depth, and the absolute value of the difference between the first height and the second height is greater than or equal to one-third of the maximum depth. The distance between each position point of the first partial line segment and the corresponding position point of the partial contour of the geometric figure in the first direction is less than or equal to one-fifth of the semi-axis length of the first axis of the geometric figure, wherein the first direction is perpendicular to the first surface, and the geometric figure meets the following requirements: Wherein -a≦y≦a, -b≦x≦b, the ratio of a to b is between 0.1 and 2, a is the semi-axis length of the first axis, and b is the semi-axis length of the second axis of the geometric figure.

[0007] A display device in one embodiment of the present invention includes a display element and at least one of the above-mentioned surface light source modules. The display element is disposed on one side of the at least one surface light source module.

[0008] The surface light source module and the display device of the embodiment of the present invention have the advantages of uniform light emission and good forward light emission effect due to the use of the microstructure with the first structural surface.

[0009] In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 FIG1 is a cross-sectional schematic diagram of a display device according to an embodiment of the present invention.

[0011] Figure 2 for Figure 1 A magnified schematic diagram of a microstructure in .

[0012] Figure 3 for Figure 2 A magnified schematic diagram of the microstructure.

[0013] Figure 4 FIG1 is a schematic top view of a light guide plate according to an embodiment of the present invention.

[0014] Figure 5 FIG1 is a schematic cross-sectional view of a single microstructure in a light guide plate according to another embodiment of the present invention.

[0015] Figure 6 FIG1 is a schematic cross-sectional view of a single microstructure in a light guide plate according to another embodiment of the present invention.

[0016] Figure 7 FIG1 is a schematic cross-sectional view of a single microstructure in a light guide plate according to another embodiment of the present invention.

[0017] Figure 8 FIG1 is a schematic cross-sectional view of a single microstructure in a light guide plate according to another embodiment of the present invention.

[0018] Figure 9 FIG1 is a schematic cross-sectional view of a single microstructure in a light guide plate according to another embodiment of the present invention.

[0019] Figure 10 FIG1 is a schematic cross-sectional view of a single microstructure in a light guide plate according to another embodiment of the present invention.

[0020] Figure 11 FIG1 is a schematic cross-sectional view of a single microstructure in a light guide plate according to another embodiment of the present invention.

[0021] Figure 12 FIG1 is a cross-sectional schematic diagram of a display device according to another embodiment of the present invention.

[0022] Figure 13 FIG1 is a cross-sectional schematic diagram of a display device according to another embodiment of the present invention.

[0023] Description of reference numerals:

[0024] 1, 1h, 1i: Display device

[0025] 10, 10f, 10g, 10h, 10i: Surface light source module

[0026] 20, 20h, 20i: Display components

[0027] 100, 100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h: Light guide plate

[0028] 101: First Surface

[0029] 102: Second surface

[0030] 103: Light incident surface

[0031] 110, 110a, 110b, 110c, 110d, 110e, 110f, 110g: Microstructure

[0032] 111, 111a, 111b, 111c, 111e, 111f, 111g: first structural surface

[0033] 112, 112b, 112c, 112f: Second structural surface

[0034] 113, 113f: third structural surface

[0035] 210: Light source element

[0036] 211a, 211b, 211h: Light

[0037] 220, 220h, 220i: Overlay

[0038] 230: Optical adhesive layer

[0039] a: semi-axis length of the first axis

[0040] b: semi-axis length of the second axis

[0041] a1, a1a, a1e, a1g: the first part of the line segment

[0042] a11: first end

[0043] a12: second end

[0044] a2, a2e: the second part of the line segment

[0045] A: Symmetrical plane

[0046] A1, A1a, A1b, A1c, A1d, A1e, A1f: First Junction

[0047] A3: The third boundary line

[0048] B: Distance

[0049] D1: First direction

[0050] D2: Second direction

[0051] G: Point

[0052] H1: First height

[0053] H2: Second height

[0054] H3: Maximum depth

[0055] H4: Maximum height

[0056] M1: first axis

[0057] M2: Second axis

[0058] O: Center

[0059] P: Point

[0060] PG, PGa, PGb, PGd, PGf, PGg: Geometric shapes

[0061] W: width

[0062] X, Y, Z: direction

[0063] θ1: first angle

[0064] θ2: Second angle

[0065] θ3: third angle

[0066] ψ: maximum width. DETAILED DESCRIPTION

[0067] The aforementioned and other technical aspects, features, and functions of this invention will be more clearly understood in the following detailed description of a preferred embodiment with reference to the accompanying drawings. Directional terms such as up, down, left, right, front, and back, used in the following embodiments, are merely references to the accompanying drawings. Therefore, the directional terms used are for illustrative purposes only and are not intended to limit this invention.

[0068] Figure 1 This is a cross-sectional diagram of a display device according to an embodiment of the present invention. Figure 1 The display device 1 of one embodiment of the present invention includes at least one surface light source module 10 and a display element 20. In this embodiment, the number of the surface light source module 10 is taken as one, but is not limited thereto. Each of the at least one surface light source modules 10 includes a light guide plate 100 and a light source element 210. The light guide plate 100 has a first surface 101 and a second surface 102 relative to each other, and a light incident surface 103 connecting the first surface 101 and the second surface 102, and the first surface 101 is provided with a plurality of microstructures 110. The light source element 210 is arranged opposite to the light incident surface 103. The light source element 210 of this embodiment includes, for example, a plurality of light-emitting units, and the above-mentioned light-emitting units are, for example, light-emitting diodes, but the present invention does not impose specific limitations on this. The display element 20 in the display device 1 of this embodiment is, for example, a reflective liquid crystal panel.

[0069] Figure 2 for Figure 1 A magnified schematic diagram of the microstructure in Figure 1. Figure 3 for Figure 2 A magnified schematic diagram of the microstructure. Figure 4 This is a top view of a light guide plate according to an embodiment of the present invention. Figures 2 to 4 In this embodiment, each microstructure 110 has a first structure surface 111 connected to the first surface 101, and each microstructure 110 has a symmetry plane A. Specifically, the microstructure 110 of this embodiment is, for example, a concave microstructure recessed from the first surface 101, and the outer contour of the microstructure 110 in a top view (i.e., the projection of the microstructure 110 on the first surface 101) is, for example, a long strip. Figure 4 As shown, the symmetry plane A passes through the geometric center of the microstructure 110, and the microstructure 110 is symmetrical (for example, mirror symmetric) about the symmetry plane A. In this embodiment, the symmetry plane A is perpendicular to the first surface 101 and the angle between the symmetry plane A and the light incident surface 103 is, for example, between 45 degrees and 90 degrees. Figure 4 As shown, for example, the angle between the symmetry plane A and the light incident surface 103 of this embodiment is 90 degrees, but the present invention does not impose a specific limitation on this. The present invention also does not impose a specific limitation on the shape and arrangement of the outer contour of the microstructure 110 in a top view. Figure 4In another embodiment, the outer contour of the projection of the microstructure 110 on the first surface 101 may be a fan-like, triangle-like, or arc-like shape (not shown).

[0070] Continuing from the above, please refer to Figure 2 and Figure 3 ,exist Figure 2 and Figure 3 In the figure, for example, the cross-sectional diagram is taken with the symmetry plane A as the cross-section. In the present embodiment, the boundary between the first structural surface 111 and the symmetry plane A has a first boundary line A1, and the first boundary line A1 includes a first partial line segment a1. The first partial line segment a1 has a first end a11 and a second end a12 opposite to each other. The first end a11 can selectively have a first height H1 (greater than 0) with respect to the first surface 101, or be located on the first surface 101 (the first height H1 is 0), and the tangents at various positions on the first partial line segment a1 have a first angle θ1 with the first surface 101. In one embodiment, the angle between the tangent of the first partial line segment a1 at the first end a11 and the first surface 101 (i.e., the first angle θ1 at the first end a11) is, for example, greater than 0 degrees and less than or equal to 25 degrees, for example, 10 degrees, but the present invention is not limited thereto. In another embodiment, the farther each position of the first boundary line A1a is from the first surface 101, the larger the angle between the tangent at each position on the first boundary line A1 and the first surface 101 is or remains unchanged, and the angle between the tangent at each position on the first boundary line A1 and the first surface 101 is less than or equal to 90 degrees; the angle of the first angle θ1 at each position on the first partial line segment a1 gradually increases from the first end a11 to the second end a12.

[0071] Please refer to Figure 2 and Figure 3 In this embodiment, the first part of the line segment a1 is similar to the part of the outline of the geometric figure PG. Specifically, the first part of the line segment a1 is similar to the part of the outline of the geometric figure PG. Figure 2 The outline of the upper right half of the figure is similar. The geometric figure PG in this embodiment is drawn with a dotted line. The geometric figure PG has a center O, for example, which is the center of symmetry of the geometric figure PG. The geometric figure PG has two symmetry axes, namely a first axis M1 and a second axis M2, wherein the first axis M1 and the second axis M2 are perpendicular to each other, and the angle between the first axis M1 and the first direction D1 is less than 10 degrees (for example, Figure 2), for example, 0 degrees, meaning that the first axis M1 and the first direction D1 are, for example, parallel, and the second axis M2 and the second direction D2 are, for example, parallel, with the first direction D1 being perpendicular to the first surface 101. In this embodiment, a is the semi-axis length of the first axis M1, meaning half the distance between the first axis M1 and the two intersection points of the geometric figure PG; b is the semi-axis length of the second axis M2, meaning half the distance between the second axis M2 and the two intersection points of the geometric figure PG. The first direction D1 is, for example, parallel to the Z direction, and the second direction D2 is, for example, parallel to the X direction.

[0072] The geometric figure PG of this embodiment complies with: Where -a≦y≦a, -b≦x≦b, and the ratio of a to b is between 0.1 and 2. In one embodiment, the ratio of a to b is, for example, 0.7 (e.g. Figure 2 and Figure 3 ), but the present invention is not limited to this. The boundary point between the first boundary line A1 (first structural surface 111) and the first surface 101 is, for example, the intersection of the first axis M1 of the geometric figure PG and the light guide plate 100. It should be noted that, in one embodiment of the present invention, the first partial line segment a1, for example, coincides with the partial contour of the geometric figure PG, wherein the geometric figure PG is, for example, a circle or an ellipse, which means that the first partial line segment a1 can be a partial contour of a perfect circle or an ellipse in mathematical definition. The first partial line segment a1 may also have a slight error with the partial contour of the geometric figure PG due to various factors in the manufacturing process. When the above-mentioned slight error is within a certain range, it is approximate to the partial contour of the geometric figure PG.

[0073] In detail, in this embodiment, Figure 3 As shown, the situation where the first partial line segment a1 is similar to the partial outline of the geometric figure PG is that: each position point of the first partial line segment a1 in the first direction D1 (such as Figure 3 The corresponding position points of the partial contour of the geometric figure PG (such as Figure 3 In other words, the error value (i.e., the distance B) between each position point of the first partial line segment a1 in the first direction D1 and the corresponding position of the partial contour of the geometric figure PG is less than or equal to one fifth of the semi-axis length a of the first axis M1 of the geometric figure PG. In another embodiment, each position point of the first partial line segment a1 in the first direction D1 (e.g., Figure 3 The corresponding position points of the partial contour of the geometric figure PG (such as Figure 3 The distance B between the points G in the geometric figure PG is, for example, less than or equal to one tenth of the semi-axis length a of the first axis M1 of the geometric figure PG.

[0074] In addition, there is a second height H2 between the second end a12 and the first surface 101, and each microstructure 110 has a maximum depth H3 (i.e., the height of each microstructure 110 in the first direction D1). The absolute value of the difference between the first height H1 and the second height H2 is greater than or equal to one-third of the maximum depth H3, preferably greater than or equal to one-half of the maximum depth H3, and more preferably greater than or equal to two-thirds of the maximum depth H3. The present invention is not limited to this. In one embodiment, the absolute value of the difference between the first height H1 and the second height H2 can be equal to the maximum depth H3, such as Figure 5 shown.

[0075] In addition, in this embodiment, the maximum depth H3 is, for example, greater than or equal to one-fourth of the semi-axis length a of the first axis M1, and less than or equal to two-thirds of the semi-axis length a of the first axis M1. For example, in one embodiment, the maximum depth H3 is, for example, 1.14 times the semi-axis length a of the first axis M1 (e.g., Figure 3 In another embodiment, the maximum depth H3 may be equal to the semi-axis length a of the first axis M1 (as shown in FIG. Figure 5 In another embodiment, the maximum depth H3 may also be approximately 0.58 times the semi-axis length a of the first axis M1 (as shown). Figure 7 The present invention does not impose any specific restrictions on this.

[0076] Please refer to Figure 1 and Figure 2 When the light provided by the light source element 210 is transmitted to the first structural surface 111, part of the light may be partially reflected or totally reflected once or multiple times on the first structural surface 111, thereby correcting the transmission path of the light and helping to improve the forward light emission effect of the surface light source module 10. For example, the light 211a is transmitted to the first partial line segment a1 of the first structural surface 111, and is reflected and then transmitted to the side of the first partial line segment a1 away from the first surface 101 and the second surface 102 in sequence, so that the light 211a is close to the forward light emission when it is emitted from the second surface 102 of the light guide plate 100. The light 211b is transmitted to the first partial line segment a1 of the first structural surface 111, and is reflected and then transmitted to the second surface 102, so that the light 211b is also close to the forward light emission when it is emitted from the second surface 102 of the light guide plate 100.

[0077] The surface light source module 10 of this embodiment further includes a cover layer 220 and an optical adhesive layer 230 . The cover layer 220 is disposed opposite to the first surface 101 . The optical adhesive layer 230 is disposed between the light guide plate 100 and the cover layer 220 and covers the plurality of microstructures 110 .

[0078] The display device 1 of this embodiment is, for example, a reflective display device. The cover layer 220 is, for example, glass or a touch panel. The surface light source module 10 is, for example, a front light module. The display element 20 is, for example, disposed opposite the second surface 102, and the optical adhesive layer 230 is, for example, disposed between the light guide plate 100 and the display element 20. Furthermore, the surface light source module 10 of this embodiment may further include an optical film (not shown) disposed between the optical adhesive layer 230 and the cover layer 220. The optical film may be, for example, a polarizer, a brightness enhancement film, or a combination thereof, to reduce stray light and improve contrast and viewing angle.

[0079] Because the surface light source module 10 of this embodiment also includes a covering layer 220 and an optical adhesive layer 230, it can reduce the stray light generated by the reflection of ambient light at the interface between the light guide plate 100 and the optical adhesive layer 230, thereby improving the visibility of the display device 1. Specifically, the light guide plate 100 of this embodiment has a first refractive index, and the optical adhesive layer 230 has a second refractive index, wherein the second refractive index is, for example, smaller than the first refractive index. For example, the difference between the first refractive index and the second refractive index is between 0.1 and 0.15. The first refractive index is, for example, between 1.5 and 1.6, such as 1.57, and the second refractive index is, for example, between 1.4 and 1.5, such as 1.42 or 1.47, but the present invention does not impose specific limitations on this. When the surface light source module 10 is applied to a display device 1 (e.g., a reflective display device) and the display device 1 is located in an area with strong ambient light, the optical adhesive layer 230 covers and fills the plurality of microstructures 110. As a result, the difference between the second refractive index and the first refractive index of the optical adhesive layer 230 is much smaller than the difference between the first refractive index and the first refractive index of air. This reduces reflection of ambient light at the interface between the light guide plate 100 and the optical adhesive layer 230, thereby improving the visibility of the display device 1. Furthermore, because the first structural surface 111 includes the first partial line segment a1, even if the difference in refractive index between the light guide plate 100 and the optical adhesive layer 230 is small, the light beam can still be totally reflected to a near-normal direction.

[0080] As described above, in this embodiment, the optical adhesive layer 230, for example, contacts at least the first portion of line segment a1. In this embodiment, the optical adhesive layer 230, for example, completely fills (or fully adheres) the gap between the light guide plate 100 and the cover layer 220. Fully filling the optical adhesive layer 230 allows for a more secure bond between the cover layer 220 and the light guide plate 100, strengthening the structure and reducing stray light. Furthermore, when the cover layer 220 is a touch panel, for example, this can enhance the touch experience.

[0081] Continue to refer Figure 3, each microstructure 110 of this embodiment is, for example, recessed from the first surface 101 as described above, and further has, for example, a second structural surface 112 and a third structural surface 113. The second structural surface 112 is, for example, connected between the first structural surface 111 and the third structural surface 113, the third structural surface 113 is, for example, connected to the first surface 101, and the second end a12 is, for example, close to the second structural surface 112. Specifically, the microstructure 110 and the symmetry plane A have a boundary line, and the point where the difference in the angle (absolute value) between the tangent lines of two adjacent points on the boundary line and the first surface 101 is greater than a specific angle value can be defined as the intersection of the first boundary line A1 (first structural surface 111) and the second structural surface 112, and the specific angle value is, for example, 30 degrees. For example, if Figure 3 As shown, the angle between the tangent line of the intersection line and the first surface 101 is equal to 85 degrees and then turns to 0 degrees, which is the intersection of the first intersection line A1 and the second structural surface 112. The third structural surface 113 and the first surface 101 have a second angle θ2, for example, which is greater than or equal to 50 degrees and less than or equal to 90 degrees. Specifically, the third structural surface 113 of this embodiment is, for example, a plane (i.e., the intersection of the third structural surface 113 and the symmetry plane A is, for example, a straight line), and the second angle θ2 is preferably close to 90 degrees.

[0082] Continuing from the above, the second structure surface 112 has a width W, for example, along the second direction D2 perpendicular to the light incident surface 103. The width W is, for example, greater than or equal to one tenth of the maximum depth H3, and, for example, less than or equal to one half of the maximum depth H3. For example, the width W is, for example, 2 μm, but the present invention does not impose a specific limitation on this. In addition, in this embodiment, the second structure surface 112 is, for example, a plane. Figure 2 and Figure 3 As shown, but the present invention is not limited thereto. In another embodiment, the second structural surface 112 may be a curved surface, such as Figure 6 The second direction is, for example, parallel to the X direction.

[0083] Please continue to refer to Figure 3 In this embodiment, the first boundary line A1 further includes, for example, a second partial line segment a2. The second partial line segment a2 connects, for example, the second end a12 of the first partial line segment a1 and the second structural surface 112. The second partial line segment a2 is, for example, a straight line. A third angle θ3 is formed between the second partial line segment a2 and the first surface 101. The third angle θ3 is, for example, between 80 and 90 degrees. In one embodiment, the third angle θ3 is, for example, 85 degrees, but the present invention is not limited thereto.

[0084] Because the surface light source module 10 of this embodiment utilizes microstructures 110 having first structured surfaces 111, the surface light source module 10 can provide a uniform and forward-emitting illumination beam directed toward the display element 20. Furthermore, the surface light source module 10 of this embodiment utilizes an optical adhesive layer 230 covering the plurality of microstructures 110, thereby enhancing the visibility of the display device 1 under strong ambient light.

[0085] Figure 5 This is a cross-sectional diagram of a single microstructure in a light guide plate according to another embodiment of the present invention. Figure 3 and Figure 5 The light guide plate 100a of this embodiment is similar to the light guide plate 100, with the primary difference being that the first boundary line A1a of this embodiment, for example, coincides with a portion of the contour of the geometric figure PGa. Specifically, the first boundary line A1a, for example, does not include the second partial line segment a2, and the angle between the tangent line at each position on the first boundary line A1a and the first surface 101 is less than or equal to 90 degrees. Specifically, the geometric figure PG is identical to the geometric figure PGa, for example, and the error between the first partial line segment a1a and the partial contour of the geometric figure PGa is negligible (e.g., less than 10 nanometers) or virtually non-existent at the scale of the microstructure 110. Therefore, it can be understood that the first partial line segment a1a coincides with a portion of the contour of the geometric figure PGa. Figure 5 In the illustrated embodiment, the boundary between the first boundary line A1a and the first surface 101 is, for example, the intersection of the first axis M1 of the geometric figure PGa and the first surface 101 of the light guide plate 100a, and is also the first end a11 of the first partial line segment a1a. Meanwhile, the second end a12 of the first partial line segment a1a overlaps with the boundary between the first structural surface 111a and the second structural surface 112. It is particularly noted that, in one embodiment, the first end a11 of the first partial line segment a1a may be selectively not located on the first surface 101, and the second end a12 of the first partial line segment a1a may also be selectively not located at the boundary between the first structural surface 111a and the second structural surface 112, that is, the length of the first partial line segment a1a is less than the length of the first boundary line A1a, and the farther each position on the first boundary line A1a is from the first surface 101, the larger the angle between the tangent line at each position on the first boundary line A1a and the first surface 101 is or remains constant, and the angle between the tangent line at each position on the first boundary line A1a and the first surface 101 is less than or equal to 90 degrees; the first angle θ1 (e.g., Figure 3 The angle (indicated) gradually increases from the first end a11 to the second end a12.

[0086] Figure 6 This is a cross-sectional diagram of a single microstructure in a light guide plate according to another embodiment of the present invention. Figure 5 and Figure 6, the light guide plate 100b of this embodiment is similar to the light guide plate 100a, and the main differences are that the geometric figure PGb of this embodiment is different from the geometric figure PGa, and the second structural surface 112b is different from the second structural surface 112. Specifically, the ratio of a to b of the geometric figure PGb of this embodiment is, for example, 1, which means that the geometric figure PGb is, for example, a circle. In addition, the first boundary line A1b of this embodiment, for example, does not coincide with a partial outline of the geometric figure PGb, and the first boundary line A1b, for example, does not have a second partial line segment a2. The second structural surface 112b of this embodiment is, for example, semicircular or arc-shaped, but the present invention does not impose specific restrictions on this.

[0087] Figure 7 This is a cross-sectional diagram of a single microstructure in a light guide plate according to another embodiment of the present invention. Figure 5 and Figure 7 The light guide plate 100c of this embodiment is similar to the light guide plate 100a. The main difference lies in the length of the first boundary line A1c and the maximum depth H3 of the microstructure 110c. Specifically, the length of the first boundary line A1c (i.e., Figure 7 The length of the trajectory from the first end a11 to the second end a12 in the microstructure 110c is, for example, less than one-quarter of the outline of the geometric figure PGa (e.g., the perimeter of an ellipse), while the length of the first boundary line A1a is, for example, equal to one-quarter of the outline of the geometric figure PGa. The maximum depth H3 of the microstructure 110c is, for example, 0.47 times the semi-axis length a of the first axis, while the maximum depth H3 of the microstructure 110a is, for example, equal to the semi-axis length a of the first axis.

[0088] Figure 8 This is a cross-sectional diagram of a single microstructure in a light guide plate according to another embodiment of the present invention. Figure 8 and Figure 5 The light guide plate 100d of this embodiment is similar to the light guide plate 100a, with the primary difference being that the geometric pattern PGd differs from the geometric pattern PGa. Specifically, the ratio of a to b in the geometric pattern PGd of this embodiment is greater than 1, for example, such as 1.375, but the present invention is not limited thereto. The first boundary line A1d of this embodiment, for example, coincides with a portion of the outline of the geometric pattern PGd, and the first boundary line A1d also, for example, does not include the second partial line segment a2.

[0089] Figure 9 This is a cross-sectional diagram of a single microstructure in a light guide plate according to another embodiment of the present invention. Figure 9 and Figure 5The light guide plate 100e of this embodiment is similar to the light guide plate 100a, and the main difference is that the first boundary line A1e of this embodiment further includes a second partial line segment a2e. Specifically, the first boundary line A1e of this embodiment includes a first partial line segment a1e and a second partial line segment a2e, wherein the first partial line segment a1e and the second partial line segment a2e are connected. Figure 5 The first partial line segment a1a is the same as the first partial line segment a2e; the second partial line segment a2e is, for example, a straight line, and the angle between the second partial line segment a2e and the first surface 101 is, for example, equal to the angle between the tangent line of the first partial line segment a1e at the second end a12 and the first surface 101. For example, in this embodiment, the angle between the second partial line segment a2e and the first surface 101 is, for example, 90 degrees, but the present invention is not limited thereto. It should be noted that the angle between the second partial line segment a2e and the first surface 101 is, for example, not greater than 90 degrees. In addition, Figure 9 The embodiment shown and Figure 5 Compared with the embodiment shown, since the second partial line segment a2e is further provided, the maximum depth H3 of the microstructure 110e is, for example, greater than the semi-axis length a of the first axis, but the present invention does not impose a specific limitation thereto.

[0090] Figure 10 This is a cross-sectional diagram of a single microstructure in a light guide plate according to another embodiment of the present invention. Figure 10 and Figure 5 The light guide plate 100f of this embodiment is similar to the light guide plate 100a, and the main difference lies in the difference between the first structural surface 111f and the third structural surface 113f, which are described in detail as follows. Figure 10 In the illustrated embodiment, the intersection of the third structural surface 113f and the symmetry plane A comprises, for example, a third intersection line A3. The third intersection line A3 is, for example, mirror-symmetric to the first intersection line A1f. Furthermore, the second structural surface 112f has a width W along a second direction D2 perpendicular to the light incident plane. The width W is, for example, greater than or equal to one-tenth of the maximum depth H3. Specifically, the geometric pattern PGf is, for example, similar to the geometric pattern PGa. Because the microstructure 110f of the light guide plate 100f of this embodiment has a mirror-symmetric third intersection line A3 and first intersection line A1f, it can be used in a surface light source module 10f with bidirectional light input.

[0091] Figure 11 This is a cross-sectional diagram of a single microstructure in a light guide plate according to another embodiment of the present invention. Figure 11 In this embodiment, each microstructure 110g is, for example, protruding from the first surface 101, and the first end a11 of the first partial line segment a1g is, for example, far away from the first surface 101, and the second end a12 is, for example, close to the first surface 101. Specifically, the geometric figure PGg is, for example, Figure 5The geometric figure PGa shown is similar to that shown in FIG. In addition, each microstructure 110g has a maximum width ψ along the second direction D2 perpendicular to the light incident surface 103, for example, and each microstructure 110g has a maximum height H4 along the first direction D1 perpendicular to the first surface 101, for example, and the maximum height H4 is less than or equal to three tenths of the maximum width ψ. When the microstructure 110g is, for example, raised from the first surface 101, the flat microstructure 110g (i.e., the ratio of the maximum height H4 to the maximum width ψ is small) helps light (such as Figure 1 as shown) is transferred to the first structural surface 111g.

[0092] It is particularly noted that the microstructure in one embodiment of the present invention is, for example, a concave microstructure that is recessed from the first surface 101, such as Figures 1 to 10 As shown, the maximum depth H3 represents the maximum depth of the concave microstructure. In another embodiment, the microstructure is, for example, convex from the first surface 101, such as Figure 11 For example, the maximum height H4 represents the maximum height of the raised microstructure. It should be noted that the maximum distance between the microstructure and the first surface 101 in the first direction D1 is equivalent to the maximum height H4 or the maximum depth H3. If the microstructure is considered to be raised or recessed from the first surface 101, the maximum height H4 can also be understood as the maximum depth H3, and vice versa.

[0093] Figure 12 This is a cross-sectional diagram of a display device according to another embodiment of the present invention. Figure 1 and Figure 12 The surface light source module 10h of this embodiment is similar to the surface light source module 10, the main difference being that the second surface 102 of the surface light source module 10h is, for example, the light emitting surface of the surface light source module 10h, and the cover layer 220h is, for example, a reflective sheet or a transparent substrate. In this case, the surface light source module 10h is, for example, a backlight module, and the display device 1h is, for example, a transparent display device or a backlight display device. Since the light guide plate 100h also has Figure 1 The microstructure 110 also helps to guide the transmission path of part of the light (e.g., light 211h) of the light source element 210, so that the surface light source module 10h can provide a forward and uniform illumination beam transmitted toward the display element 20h. In addition, the display element 20h of this embodiment is, for example, a transmissive liquid crystal panel. In addition, the surface light source module 10h may also include an optical film (not shown) disposed between the light guide plate 100h and the display element 20h, wherein the light guide plate 100h and the optical film may be fully bonded or have an air gap, and the display element 20h and the optical film may also be fully bonded or have an air gap.

[0094] Figure 13This is a cross-sectional diagram of a display device according to another embodiment of the present invention. Figure 1 and Figure 13 The display device 1i of one embodiment of the present invention includes, for example, a display element 20i and two surface light source modules 10i. The display element 20i is disposed between the two surface light source modules 10i. The display device 1i is, for example, a bidirectional transparent display device. Figure 1 The surface light source module 10 is similar to the surface light source module 10, with the main difference being that the covering layer 220i of the surface light source module 10i is, for example, a transparent substrate, and the display element 20i is, for example, a transparent display panel, which can display the two surface light source modules 10i separately, but the present invention is not limited to this. The microstructure 110 of the surface light source module 10i of this embodiment is the same as the microstructure 110 of the surface light source module 10, but the present invention is not limited to this. In another embodiment, the microstructure 110 of the surface light source module 10i may be microstructure 110a, microstructure 110b, microstructure 110c, microstructure 110d, microstructure 110e, microstructure 110f or microstructure 110g. In addition, the microstructures 110 of the two surface light source modules 10i of this embodiment are, for example, the same, but the present invention does not impose specific restrictions on this. In another embodiment, the microstructures 110 of the two surface light source modules 10i may be different.

[0095] It should be noted that the light source elements 210 of the two surface light source modules 10i of this embodiment are arranged opposite to each other. However, the present invention does not impose a specific limitation on this. In another embodiment, the light source elements 210 of the two surface light source modules 10i can be arranged on the same side, for example, Figure 13 to the left or right side of the

[0096] In summary, because the surface light source module of an embodiment of the present invention and the microstructures of the light guide plate of the display device have a first portion of the first boundary line, they have the advantages of uniform light emission and excellent forward light emission. In addition, the surface light source module of an embodiment of the present invention has an optical adhesive layer covering the multiple microstructures. When the surface light source module is used in a display device (such as the bidirectional transparent display device of the present invention or other unidirectional display device), it helps to improve the visibility of the display device under strong ambient light.

[0097] However, what is described above is only a preferred embodiment of the present utility model, and it should not be used to limit the scope of implementation of the present utility model. That is, all simple equivalent changes and modifications made in accordance with the claims of the present utility model and the content of the utility model are still within the scope of the present utility model patent. In addition, any embodiment or claim of the present utility model does not necessarily achieve all the purposes, advantages or features disclosed in the utility model. In addition, the abstract and title (utility model name) are only used to assist in patent document retrieval and are not used to limit the scope of rights of the present utility model. In addition, the terms "first", "second", etc. mentioned in this specification or claims are only used to name the name of the element or to distinguish different embodiments or ranges, and are not used to limit the upper or lower limit of the number of elements.

Claims

1. A surface light source module, characterized in that: The surface light source module includes a light guide plate and a light source element, wherein: The light guide plate has a first surface and a second surface opposite to each other, and a light incident surface connecting the first surface and the second surface, wherein the first surface is provided with a plurality of microstructures; and The light source element is arranged opposite to the light incident surface, Each of the plurality of microstructures has a first structural surface connected to the first surface, each of the plurality of microstructures has a symmetry plane, the symmetry plane is perpendicular to the first surface, the intersection of the first structural surface and the symmetry plane has a first intersection line, the first intersection line includes a first partial line segment, the first partial line segment has a first end and a second end opposite to each other, There is a first height between the first end and the first surface, there is a second height between the second end and the first surface, each of the plurality of microstructures has a maximum depth, and an absolute value of a difference between the first height and the second height is greater than or equal to one third of the maximum depth, The distance between each position point of the first partial line segment and the corresponding position point of the partial outline of a geometric figure in a first direction is less than or equal to one fifth of the semi-axis length of the first axis of the geometric figure, wherein the first direction is perpendicular to the first surface, and the geometric figure meets the following requirements: Wherein -a≦y≦a, -b≦x≦b, the ratio of a to b is between 0.1 and 2, a is the semi-axis length of the first axis, and b is the semi-axis length of the second axis of the geometric figure.

2. The surface light source module according to claim 1, wherein: The angle between the symmetry plane and the light incident surface is between 45 degrees and 90 degrees, the angle between the first axis and the first direction is less than 10 degrees, and the tangent at each position on the first part of the line segment has a first angle with the first surface, and the angle of each first angle gradually increases from the first end to the second end.

3. The surface light source module according to claim 1, wherein: The maximum depth is greater than or equal to one quarter of the semi-axis length of the first axis and less than or equal to three half of the semi-axis length of the first axis.

4. The surface light source module according to claim 1, wherein: An included angle between a tangent line of the first portion of line segments at the first end and the first surface is greater than 0 degrees and less than or equal to 25 degrees.

5. The surface light source module according to claim 1, wherein: The surface light source module further includes a covering layer and an optical adhesive layer, wherein: The covering layer is disposed opposite to the first surface; and The optical adhesive layer is disposed between the light guide plate and the cover layer and covers the plurality of microstructures, wherein the optical adhesive layer at least contacts the first portion of the line segments.

6. The surface light source module according to claim 1, wherein: Each of the plurality of microstructures is recessed from the first surface, and each of the plurality of microstructures further has a second structure surface and a third structure surface, wherein the second structure surface is connected between the first structure surface and the third structure surface, the third structure surface is connected to the first surface, and the second end is close to the second structure surface; as well as There is a second angle between the third structural surface and the first surface, the second angle is greater than or equal to 50 degrees and less than or equal to 90 degrees, and the second structural surface has a width along a second direction perpendicular to the light incident surface, and the width is greater than or equal to one tenth of the maximum depth.

7. The surface light source module according to claim 6, wherein: The first boundary line also includes a second partial line segment, which connects the second end of the first partial line segment and the second structural surface. The second partial line segment is a straight line, and there is a third angle between the second partial line segment and the first surface, and the third angle is between 80 degrees and 90 degrees.

8. The surface light source module according to claim 1, wherein: Each of the plurality of microstructures is recessed from the first surface, and each of the plurality of microstructures further has a second structure surface and a third structure surface, wherein the second structure surface is connected between the first structure surface and the third structure surface, the third structure surface is connected to the first surface, and the second end is close to the second structure surface; The intersection of the third structural surface and the symmetry plane has a third boundary line, the third boundary line is mirror-symmetrical to the first boundary line, and the second structural surface has a width along a second direction perpendicular to the light incident surface, and the width is greater than or equal to one tenth of the maximum depth.

9. The surface light source module according to claim 1, wherein: Each of the plurality of microstructures protrudes from the first surface, the first end of the first portion of the line segment is away from the first surface, and the second end is close to the first surface.

10. The surface light source module according to claim 9, wherein: A surface of each of the plurality of microstructures connected to the first surface has a maximum width along a second direction perpendicular to the light incident surface, and each of the plurality of microstructures has a maximum height, which is less than or equal to three tenths of the maximum width.

11. The surface light source module according to claim 1, wherein: The surface light source module further includes a covering layer, which is arranged opposite to the first surface, wherein the covering layer is glass or a touch panel.

12. The surface light source module according to claim 1, wherein: The surface light source module further includes a covering layer, which is arranged opposite to the first surface, wherein the second surface is the light emitting surface of the surface light source module, and the covering layer is a reflective sheet or a transparent substrate.

13. A display device, characterized in that: The display device includes a display element and at least one light source module, wherein: The display element is disposed on one side of the at least one light source module. Each of the at least one light source module includes a light guide plate and a light source element, wherein: The light guide plate has a first surface and a second surface opposite to each other, and a light incident surface connecting the first surface and the second surface, the second surface is adjacent to the display element, and the first surface is provided with a plurality of microstructures; and The light source element is arranged opposite to the light incident surface, Each of the plurality of microstructures has a first structural surface connected to the first surface, each of the plurality of microstructures has a symmetry plane, the symmetry plane is perpendicular to the first surface, the intersection of the first structural surface and the symmetry plane has a first intersection line, the first intersection line includes a first partial line segment, the first partial line segment has a first end and a second end opposite to each other, There is a first height between the first end and the first surface, there is a second height between the second end and the first surface, each of the plurality of microstructures has a maximum depth, and an absolute value of a difference between the first height and the second height is greater than or equal to one third of the maximum depth, The distance between each position point of the first partial line segment and the corresponding position point of the partial outline of a geometric figure in a first direction is less than or equal to one fifth of the semi-axis length of the first axis of the geometric figure, wherein the first direction is perpendicular to the first surface, and the geometric figure meets the following requirements: Wherein -a≦y≦a, -b≦x≦b, the ratio of a to b is between 0.1 and 2, a is the semi-axis length of the first axis, and b is the semi-axis length of the second axis of the geometric figure.

14. The display device according to claim 13, wherein: Each of the at least one light source modules further includes a covering layer and an optical adhesive layer, wherein: The covering layer is disposed opposite to the first surface; and The optical adhesive layer is disposed between the light guide plate and the cover layer and covers the plurality of microstructures. The optical adhesive layer at least contacts the first portion of the line segments, and the covering layer is a transparent substrate or a reflective sheet.

15. The display device according to claim 13, wherein The display device includes two surface light source modules, wherein the display element is configured between the two surface light source modules.

Images