Drawings
Fig. 1 is a schematic perspective view of a light source module according to an embodiment of the present invention.
Fig. 2 is a schematic cross-sectional view of fig. 1.
Fig. 3A is a schematic view of a side facing the first light incident surface of the light guide plate of fig. 1.
Fig. 3B is a schematic view of a side facing the first surface of the light guide plate of fig. 1.
Fig. 4A is a schematic cross-sectional view of a strip-shaped microstructure according to an embodiment of the present invention in an extending direction.
Fig. 4B and 4C show other embodiments of the strip-shaped microstructure according to the present invention.
Fig. 5 is a schematic cross-sectional view of a light source module according to another embodiment of the present invention.
Fig. 6 is a schematic cross-sectional view of a light source module according to another embodiment of the present invention.
Fig. 7 is a schematic cross-sectional view of a light source module according to another embodiment of the present invention.
List of reference numerals
1. 1a, 1b, 1 c: light source module
10. 10a, 10b, 10 c: light guide plate
20: first light emitting element
30: second light emitting element
100. 100 b: plate body
110: first light incident surface
120: light emitting surface
130: first side
130 b: second light incident surface
140: bottom surface
141: diffusion microstructure
200. 200a, 200b, 200 c: strip-shaped microstructure
201: first end
202: second end
203. 203 a: light-emitting curved surface
210. 210a, 210 c: a first gradually changing part
220. 220 c: flat part
230. 230 c: second gradual change portion
A: direction of arrangement
B: a first direction
CR: radius of curvature
D: distance between each other
E: direction of extension
F1, F2, F3, F4: length of
H1, H2, H3, H4, H5: maximum height
L1, L2: light ray
W1, W3: maximum width
θ 1, θ 2: and (4) an included angle.
Detailed Description
The foregoing and other technical and scientific aspects, features and advantages of the present invention will be apparent from the following detailed description of a preferred embodiment, which is to be read in connection with the accompanying drawings. Directional terms as referred to in the following examples, for example: up, down, left, right, front or rear, etc., are simply directions with reference to the drawings. Accordingly, the directional terminology is used for purposes of illustration and is in no way limiting.
Fig. 1 is a schematic perspective view of a light source module according to an embodiment of the present invention. Fig. 2 is a schematic cross-sectional view of fig. 1. Referring to fig. 1 and fig. 2, a light source module 1 of the present embodiment includes a light guide plate 10 and a plurality of first light emitting elements 20. The light guide plate 10 includes a plate body 100 and a plurality of strip-shaped microstructures 200. The plate body 100 has a first light incident surface 110 and a light emitting surface 120, the light emitting surface 120 is adjacent to the first light incident surface 110, the light guide plate further includes a first surface 130, and the first light incident surface 110 is opposite to the first surface 130. In the present embodiment, the light emitting surface 120 is connected between the first light incident surface 110 and the first surface 130, for example. The plurality of strip microstructures 200 are disposed on the light emitting surface 120. Each strip-shaped microstructure 200 has a first end 201 and a second end 202, is arranged along an arrangement direction a parallel to the first light incident surface 110, and extends along an extension direction E. The extending direction E is, for example, perpendicular to the first light incident surface 110, but not limited thereto. The first end 201 is close to the first light incident surface 110, and the second end 202 is close to the first surface 130, i.e. away from the first light incident surface 110. The first ends 201 of the plurality of bar-shaped microstructures 200 are disposed adjacent to the first light incident surface 110, but not limited thereto. In another embodiment, the first end 201 may be disposed near but not connected to the first light incident surface 110. The second ends 202 of the plurality of bar-shaped microstructures 200 are disposed adjacent to the first surface 130, for example, but not limited thereto. In another embodiment, the second end 202 may be disposed proximate to, but not connected to, the first side 130.
In the present embodiment, the plurality of bar-shaped microstructures 200 are, for example, evenly disposed on the entire surface of the light emitting surface 120, but not limited thereto. In another embodiment, the light emitting surface 120 further has a blank region where the bar-shaped microstructures 200 are not disposed.
The plurality of first light-emitting elements 20 are disposed opposite to the first light incident surface 110 of the plate body 100 and are configured to emit a light L1 to enter the first light incident surface 110. The number of the first light emitting elements 20 in fig. 1 is three, but not limited thereto. The first light emitting element 20 can be a Light Emitting Diode (LED), but the present invention is not limited to the kind of light source.
Referring to fig. 2, each of the bar-shaped microstructures 200 further has a first gradually varying portion 210, wherein the first gradually varying portion 210 is connected to the first end 201, and the maximum height of the first gradually varying portion 210 in a first direction B perpendicular to the light emitting surface 120 (e.g., a normal direction of the light emitting surface 120) gradually increases from the first end 201 toward the second end 202. In the present embodiment, each strip-shaped microstructure 200 further has, for example, a flat portion 220 connected to the first gradual change portion 210 and extending to the second end 202. The maximum height of the flat portion 220 in the first direction B is the same from the end connecting the first gradually varying portion 210 to the second end 202. Specifically, the first gradually-varying portion 210 has a maximum height H1 at the connection with the first end 201, the end of the first gradually-varying portion 210 away from the first end 201 and connected with the flat portion 220 has a maximum height H2, and the flat portion 220 has a maximum height H3. Wherein the maximum height H1 is less than the maximum height H2, and the maximum height H2 is equal to the maximum height H3. The maximum height H1 is, for example, 0.1um to 2um, and the maximum height H3 is, for example, 5um to 20um, but is not limited thereto. In addition, in the present embodiment, the length F1 of the first gradual change portion 210 of each bar-shaped microstructure 200 in the extending direction E is half of the length F2 of each bar-shaped microstructure 200 in the extending direction E, and the length F3 of the flat portion 220 of each bar-shaped microstructure 200 in the extending direction E is also half of the length F2 of each bar-shaped microstructure 200 in the extending direction E, but is not limited thereto. The length F1 of the first gradually-changing portion 210 in the extending direction E can be adjusted according to different design requirements.
Fig. 3A is a schematic view of a side facing the first light incident surface of the light guide plate of fig. 1. Fig. 3B is a schematic view of a side facing the first surface of the light guide plate of fig. 1. Referring to fig. 1, fig. 3A and fig. 3B, each of the strip-shaped microstructures 200 has a light-emitting curved surface 203, the curvature radius CR of the light-emitting curved surface 203 in a direction perpendicular to the extending direction E is the same from the first end 201 to the second end 202, and the distance D between the centers of any two adjacent strip-shaped microstructures 200 is the same from the first end 201 to the second end 202. Specifically, the radius of curvature CR is, for example, 10 to 300um, but is not limited thereto.
The first gradually-varying portion 210 of each strip-shaped microstructure 200 is connected to the first end 201 (adjacent to the first light incident surface 110 of the plate body 100) and has a maximum height H1 and a maximum width W1 in the arrangement direction a; the flat portion 220 of each strip-shaped microstructure 200 is connected to the second end 202 (adjacent to the first face 130 of the plate body 100) and has a maximum height H3 and a maximum width W3 in the arrangement direction a. Since the curvature radius CR of the curved light-exiting surface 203 is the same from the first end 201 to the second end 202, the ratio (H1/W1) of the maximum height H1 to the maximum width W1 at the position where the first gradually-changing portion 210 connects to the first end 201 is smaller than the ratio (H3/W3) of the maximum height H3 to the maximum width W3 at the position where the flat portion 220 connects to the second end 202, and the ratio (not shown) of the maximum height to the maximum width at the position where the first gradually-changing portion 210 connects to the flat portion 220 is equal to the ratio of the maximum height H3 to the maximum width W3 at the position where the flat portion 220 is adjacent to the second end 202.
In the present embodiment, the first ends 201 of the plurality of bar-shaped microstructures 200 are separated from each other, and the second ends 202 are connected to each other, for example, but not limited thereto. In another embodiment, the first ends 201 of the plurality of bar-shaped microstructures 200 are separated from each other, and the second ends 202 are separated from each other. In addition, the shape of the bar-shaped microstructure 200 at the second end is, for example, a semi-cylinder, but is not limited thereto.
In the light source module 1 of the present embodiment, the maximum height of the first gradual change portion 210 of the strip-shaped microstructure 200 of the light guide plate 10 in the first direction B is lower than that of the first end 201, and when the height is lower, the light emitting effect of the light emitting surface 120 on the side adjacent to the light incident surface 110 can be reduced, so that the hot spot phenomenon of uneven brightness is improved; the maximum height of the first gradually-changing portion 210 in the first direction B is higher at the maximum height of the second end 202, so that the light emitting effect can be improved, and the situation that the brightness of the light emitted from the light emitting surface 120 is insufficient at the side far away from the light incident surface 110 (adjacent to the first surface 130 of the plate body 100) can be improved. In other words, since the curvature radii CR are the same, when the ratio of the maximum height to the maximum width of the cross section of the strip-shaped microstructure 200 is smaller, the light-emitting effect of the light guide plate 10 is reduced; when the ratio of the maximum height to the maximum width of the cross section of the strip-shaped microstructure 200 is large, the light-emitting effect of the light guide plate 10 is improved. Therefore, the overall brightness uniformity of the light emitting surface 120 of the light guide plate 10 can be improved.
Referring to fig. 2, the plate body 100 of the light guide plate 10 further has a bottom surface 140, and the bottom surface 140 is adjacent to the light incident surface 110 and the first surface 130 and is opposite to the light emitting surface 120. In order to further improve the light emitting effect of the light emitting surface 120 on the side away from the light incident surface 110, the bottom surface has a plurality of diffusion microstructures 141, for example, and the distribution density of the diffusion microstructures 141 gradually becomes denser from the direction close to the light incident surface 110 toward the direction away from the light incident surface 110. In the present embodiment, the diffusing microstructures 141 may be dots or other microstructures capable of diffusing the light L1. The distribution density of the plurality of diffusion microstructures 141 can be adjusted according to different design requirements.
Fig. 4A is a schematic cross-sectional view of a strip-shaped microstructure according to an embodiment of the present invention in an extending direction. Fig. 4B and 4C show other embodiments of the strip-shaped microstructure according to the present invention. Referring to fig. 4A to 4C, in the strip-shaped microstructure 200 of the present embodiment, the maximum height of the first gradually varying portion 210 increases in a linear manner from the first end 201 to the second end 202, that is, the light-emitting curved surface 203 of the first gradually varying portion 210 is an inclined straight line on the cross-sectional view of fig. 4A. In addition, the connection between the first gradually varying portion 210 and the flat portion 220 has an included angle θ 1. The strip-shaped microstructure 200 of the present invention may also have other designs. For example, the maximum height of the first gradually changing portion 210 increases from the first end 201 to the second end 202 in a non-linear manner, that is, the light exit curved surface 203a of the first gradually changing portion 210 is an inclined curve, as shown in fig. 4B. Alternatively, the included angle θ 2 at the junction of the first gradually-varying portion 210 and the flat portion 220 is a rounded chamfer as shown in fig. 4C, and the radius of curvature of the rounded chamfer is, for example, 40mm, but is not limited thereto. The above different designs can be used independently or in combination, and the present invention is not limited in particular.
Fig. 5 is a schematic cross-sectional view of a light source module according to another embodiment of the present invention. Referring to fig. 5, the light source module 1a of the present embodiment has a similar structure and advantages to the light source module 1 described above, but the difference is that in the light source module 1a of the present embodiment, the first gradually varying portion 210a of the strip-shaped microstructure 200a on the light guide plate 10a extends from the first end 201 to the second end 202. Specifically, the strip-shaped microstructure 200a does not have the flat portion 220, and the maximum height of the first gradual change portion 210a in the light outgoing direction B increases from the first end 201 to the second end 202.
Fig. 6 is a schematic cross-sectional view of a light source module according to another embodiment of the present invention. Referring to fig. 6, the light source module 1b of the present embodiment has a similar structure and advantages to the light source module 1 described above, and only the main differences of the structure will be described below. The light source module 1b of the present embodiment further includes a plurality of second light emitting elements 30, in fig. 1, the first surface 130 of the light guide plate 10 of the light source module 1 corresponds to the second light incident surface 130b of the plate body 100b of the light guide plate 10b of the light source module 1b in the present embodiment, the second light incident surface 130b is adjacent to the light emitting surface 120 and is opposite to the first light incident surface 110, and the plurality of second light emitting elements 30 are disposed opposite to the second light incident surface 130b and are used for emitting light L2 to enter the second light incident surface 130 b. Each of the bar-shaped microstructures 200B further has a second gradually varying portion 230 connected to the first gradually varying portion 210 and extending to the second end 202, wherein the maximum height of the second gradually varying portion 230 in the first direction B increases from the second end 202 to the first end 201. Specifically, the bar-shaped microstructure 200b does not have the flat portion 220, the second gradually varying portion 230 has a maximum height H4 at the position connected to the second end 202, and the end of the second gradually varying portion 230 away from the second end 202 and connected to the first gradually varying portion 210 has a maximum height H5, wherein the maximum height H4 is less than the maximum height H5. The maximum height H4 is, for example, 0.1um to 2um, and the maximum height H5 is, for example, 5um to 20um, but is not limited thereto.
In the present embodiment, the first ends 201 of the plurality of bar-shaped microstructures 200b are separated from each other, and the second ends 202 are separated from each other. The connection points of the first ends 201 and the second ends 202 of the plurality of bar-shaped microstructures 200b may be, for example, separated from each other or connected to each other.
Referring to fig. 6, when light enters from two sides, the middle region of the light guide plate 10b may have insufficient brightness, so in addition to the arrangement of the strip-shaped microstructures 200b, in order to correspond to the arrangement manner of light entering from two sides, the distribution density of the plurality of diffusion microstructures 141 of the bottom surface 140b gradually becomes dense from the direction close to the first light entering surface 110 toward the direction away from the first light entering surface 110, and then gradually becomes sparse, and the region with the highest distribution density corresponds to the connection point of the first gradual change portion 210 and the second gradual change portion 230, so as to further enhance the light exiting effect.
Fig. 7 is a schematic cross-sectional view of a light source module according to another embodiment of the present invention. Referring to fig. 7, the light source module 1c of the present embodiment has similar structure and advantages to the light source module 1b described above, but the difference is that in the light source module 1c of the present embodiment, the strip-shaped microstructure 200c on the light guide plate 10c further has a flat portion 220 c. The flat portion 220c is connected between the first gradually changing portion 210c and the second gradually changing portion 230c, the maximum heights of the flat portions 220c in the first direction B are the same, and the maximum heights of the second gradually changing portion 230c in the first direction B are gradually increased from the second end 202 to the first end 201. In the present embodiment, the length F1 of the first gradual change portion 210c of each bar-shaped microstructure 200c in the extending direction E is 1/3 of the length F2 of each bar-shaped microstructure 200c in the extending direction E, the length F3 of the flat portion 220c of each bar-shaped microstructure 200c in the extending direction E is 1/3 of the length F2 of each bar-shaped microstructure 200c in the extending direction E, and the length F4 of the second gradual change portion 230c of each bar-shaped microstructure 200c in the extending direction E is 1/3 of the length F2 of each bar-shaped microstructure 200c in the extending direction E, but is not limited thereto. The lengths F1, F3, F4 may be adjusted according to different design requirements.
The strip-shaped microstructures 200a, 200B, and 200C used in the light source modules 1a, 1B, and 1C may also be gradually increased in a non-linear manner by using the maximum height of the gradual change portion as shown in fig. 4B, or the included angle of the connection portion is a rounded chamfer as shown in fig. 4C, which is not particularly limited by the present invention. The shape of the bar-shaped microstructures 200a, 200b, and 200c is not limited to a semi-cylindrical shape.
To sum up, in the light source module of the embodiment of the present invention, the maximum height of the first gradual change portion of the strip-shaped microstructure on the light guide plate in the first direction is lower than the position adjacent to the first end, because the curvature radius of the light-emitting curved surface of the strip-shaped microstructure in the direction perpendicular to the extending direction is the same from the first end to the second end, the ratio of the maximum height to the maximum width is smaller when the height is lower, and then the light-emitting effect of the side of the light-emitting surface adjacent to the light-in surface can be reduced, and the hot spot phenomenon of uneven brightness can be improved; the maximum height of the first gradual change portion in the first direction gradually increases from the first end to the second end, so that the maximum height of the strip-shaped microstructure at the second end is higher, the ratio of the maximum height to the maximum width of the strip-shaped microstructure is larger when the height is higher, the light emitting effect can be further improved, and the condition that the brightness of the light emitted from the light emitting surface is insufficient on the side far away from the light incident surface is improved. Therefore, the overall brightness uniformity of the light-emitting surface of the light guide plate can be improved.
The above description is only a preferred embodiment of the present invention, and the scope of the present invention should not be limited thereby, and all the simple equivalent changes and modifications made according to the claims and the contents of the specification should be included in the scope of the present invention. Moreover, it is not necessary for any embodiment or claim of the invention to achieve all of the objects, advantages, or features disclosed herein. Furthermore, the abstract and the title of the specification are provided only for assisting the retrieval of patent documents and are not intended to limit the scope of the present invention. Furthermore, the terms "first," "second," and the like in the description and in the claims are used for naming elements (elements) or distinguishing between different embodiments or ranges, and are not intended to limit the upper or lower limit on the number of elements.