Light source module

Abstract

This invention provides a light source module. [Solution] The light source module includes a light guide plate, a first light source, a second light source, a plurality of first optical microstructures, and a plurality of second optical microstructures, wherein the plurality of first optical microstructures corresponding to the first light source and the plurality of second optical microstructures corresponding to the second light source are provided on the bottom surface of the light guide plate and each has a pattern reflective surface and an off-axis reflective surface facing the first light source and the second light source, respectively, the pattern reflection angle between the pattern reflective surface and the virtual extending surface of the bottom surface is 25 degrees or more and 60 degrees or less, and the off-axis reflection angle between the off-axis reflective surface and the virtual extending surface of the bottom surface is 10 degrees or more and 20 degrees or less. The light source module according to the present invention can display a stereoscopic image and can switch the light emission angle range.

Description

[Technical Field]

[0001] The present invention relates to an optical module, and particularly to a light source module. [Background Art]

[0002] With the advancement of lighting technology, in addition to lighting fixtures that generally provide a lighting function, lighting panels that further provide decorative effects have emerged on the market. In such a lighting panel, optical microstructures are formed on the bottom surface of a light guide plate, and the positions of the respective optical microstructures and the angles of their reflecting surfaces are arranged according to the effect to be displayed by the lighting panel. After light emitted from a light source enters from the side surface (light incident surface) of the light guide plate, it is transmitted to the light exiting surface of the light guide plate by reflection of the optical microstructures and exits therethrough. This allows a user to see patterns or characters formed by light on the light exiting surface side of the light guide plate.

[0003] In recent years, in order to improve the visual experience of observers, there has been an increasing demand for expressing more vivid images using lighting panels. Among these, techniques have been proposed that use various optical microstructures to guide light emitted from a point source to different viewing angles. Although this has been realized to allow a user to see different images at different viewing angles, the light exit angle of the light source limits the size of displayable patterns, which causes the problem of low display brightness.

[0004] The content of the "Background Art" paragraph is for assisting understanding of the content of the present invention. The content described in the "Background Art" paragraph may include prior arts other than those that are grasped by a person skilled in the art having common general knowledge. With respect to the content described in the "Background Art" paragraph, any content that represents the problems to be solved by the content of "Background Art" or one or more embodiments of the present invention is not something that has already been grasped or acknowledged by a person skilled in the art having common general knowledge before the filing of the present invention. [Summary of the Invention] [Problem to be Solved by the Invention]

[0005] This invention provides a light source module that can display stereoscopic images and has a switchable light emission angle range.

[0006] Other objects and advantages of the present invention will become even clearer from the technical features disclosed herein. [Means for solving the problem]

[0007] To achieve one, part, or all of the above objectives, or any other objective, the present invention provides a light source module comprising a light guide plate, a first light source, a second light source, a plurality of first optical microstructures, and a plurality of second optical microstructures, wherein the light guide plate has a bottom surface and a first light-receiving surface and a second light-receiving surface connected to the bottom surface and facing each other, the first light source is provided on the side of the light guide plate toward the first light-receiving surface, the second light source is provided on the side of the light guide plate toward the second light-receiving surface, the plurality of first optical microstructures are provided on the bottom surface of the light guide plate and each has a first pattern reflective surface facing the first light source and a first off-axis reflective surface facing the second light source, and a first pattern between the first pattern reflective surface and the virtual extending surface of the bottom surface The present invention provides a light source module having a first off-axis reflection angle, a first off-axis reflection angle between the first off-axis reflection surface and the virtual extending surface of the bottom surface, the plurality of second optical microstructures provided on the bottom surface of the light guide plate and each having a second pattern reflection surface facing the second light source and a second off-axis reflection surface facing the first light source, a second pattern reflection angle between the second pattern reflection surface and the virtual extending surface of the bottom surface, a second off-axis reflection angle between the second off-axis reflection surface and the virtual extending surface of the bottom surface, the first pattern reflection angle and the second pattern reflection angle being 25 degrees or more and 60 degrees or less, and the first off-axis reflection angle and the second off-axis reflection angle being 10 degrees or more and 20 degrees or less. [Effects of the Invention]

[0008] As described above, in a light source module according to one embodiment of the present invention, the first light source and the second light source are provided so as to correspond to two opposing light-receiving surfaces of the light guide plate, and the bottom surface of the light guide plate is provided with a plurality of first optical microstructures corresponding to the first light source and a plurality of second optical microstructures corresponding to the second light source. Since the angle of the patterned reflective surface of each optical microstructure facing the corresponding light source with respect to the bottom surface is greater than the angle of the off-axis reflective surface facing the non-corresponding light source with respect to the bottom surface, the patterned reflective surface of the optical microstructure can guide the light rays emitted by the corresponding light source to the required viewing angle, and the off-axis reflective surface can guide the light rays emitted by the non-corresponding light source outside the required viewing angle. According to the corresponding arrangement relationship of the two sets of light sources and optical microstructures described above, the light source module can have a stereoscopic image display function or a switchable light emission angle range.

[0009] To make the above-mentioned features and advantages of the present invention clearer, embodiments will be described in detail below with reference to the drawings. [Brief explanation of the drawing]

[0010] [Figure 1] This is a bottom view of a light source module according to a first embodiment of the present invention. [Figure 2] Figure 1 is a cross-sectional view of the light source module. [Figure 3] This is a light emission distribution diagram when both the first and second light sources of the light source module in Figure 1 are enabled. [Figure 4A] Figure 1 is a schematic diagram of the first viewing angle pattern formed by a plurality of first optical microstructures. [Figure 4B] Figure 1 is a schematic diagram of the second viewing angle pattern formed by multiple second optical microstructures. [Figure 5A] Figure 1 is a magnified view of the optical microstructure. [Figure 5B] Figures 5B and 5C are enlarged views of other modified examples of the optical microstructure shown in Figure 1. [Figure 5C] Figures 5B and 5C are enlarged views of other modified examples of the optical microstructure shown in Figure 1. [Figure 6] This is a top view of a light source module according to a second embodiment of the present invention. [Figure 7] Figure 6 is a cross-sectional view of the light source module. [Figure 8A] Figure 6 is a schematic diagram of the first viewing angle pattern formed by multiple first optical microstructures. [Figure 8B] Figure 6 is a schematic diagram of the second viewing angle pattern formed by multiple second optical microstructures. [Figure 8C] Figure 6 is a schematic diagram of the third viewing angle pattern formed by multiple third optical microstructures. [Figure 8D] Figure 6 is a schematic diagram of the fourth viewing angle pattern formed by multiple fourth optical microstructures. [Figure 9A] Figures 9A and 9B are cross-sectional views of a light source module according to a third embodiment of the present invention. [Figure 9B] Figures 9A and 9B are cross-sectional views of a light source module according to a third embodiment of the present invention. [Figure 10] This is a cross-sectional view of a light source module according to a fourth embodiment of the present invention. [Modes for carrying out the invention]

[0011] The above or other technical content, features, and effects of the present invention will become apparent as shown in the detailed description of preferred embodiments with reference to the following drawings. The directional terms such as “up,” “down,” “left,” “right,” “front,” and “back” used in the following embodiments are merely descriptive terms used to indicate direction when referring to the drawings. Therefore, the directional terms used are for illustrative purposes only and not to limit the present invention.

[0012] FIG. 1 is a bottom view of a light source module according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of the light source module of FIG. 1. FIG. 3 is a light output distribution diagram when both the first light source and the second light source of the light source module in FIG. 1 are enabled. FIG. 4A is a schematic diagram of a first viewing angle pattern formed by the plurality of first optical microstructures in FIG. 1. FIG. 4B is a schematic diagram of a second viewing angle pattern formed by the plurality of second optical microstructures in FIG. 1. FIG. 5A is an enlarged view of the optical microstructure in FIG. 1. FIGS. 5B and 5C are enlarged views of other modified examples of the optical microstructure in FIG. 1.

[0013] As shown in FIGS. 1 and 2, a light source module 10 includes a light guide plate LGP, a first light source LS1, a second light source LS2, a plurality of first optical microstructures OMS1 and a plurality of second optical microstructures OMS2. The light guide plate LGP has a first light incident surface IS1, a second light incident surface IS2 and a bottom surface BS. The first light incident surface IS1 and the second light incident surface IS2 face each other, and both are connected to the bottom surface BS. In this embodiment, the first light incident surface IS1 and the second light incident surface IS2 may be parallel to each other, but are not limited thereto.

[0014] The first light source LS1 is provided on a side of the first light incident surface IS1 of the light guide plate LGP, and emits a plurality of light beams L1 toward the first light incident surface IS1. The second light source LS2 is provided on a side of the second light incident surface IS2 of the light guide plate LGP, and emits a plurality of light beams L2 toward the second light incident surface IS2. In this embodiment, the first light source LS1 and the second light source LS2 are, for example, linear light sources (e.g., light bars), and extend along a long axis direction (e.g., direction X) of the first light incident surface IS1 or the second light incident surface IS2 of the light guide plate LGP. For example, the linear light source includes a plurality of light emitting diodes (or other light emitting elements), and the light emitting diodes are arranged in a single row (strip shape) along the long axis direction of the first light incident surface IS1 or the second light incident surface IS2.

[0015] The plurality of first optical microstructures OMS1 and the plurality of second optical microstructures OMS2 are provided on the bottom surface BS of the light guide plate LGP. Preferably, the ratio of the orthographic projection area of the plurality of first optical microstructures OMS1 on the bottom surface BS to the area of the bottom surface BS may be 0.8 or less, and the ratio of the orthographic projection area of the plurality of first optical microstructures OMS1 on the bottom surface BS to the orthographic projection area of the plurality of second optical microstructures OMS2 on the bottom surface BS may be greater than 0.8 and less than 1.2. For example, the plurality of first optical microstructures OMS1 and the plurality of second optical microstructures OMS2 may be alternately arranged substantially along the normal direction (e.g., direction Y) of the first light incident surface IS1 or the second light incident surface IS2, but the arrangement is not limited thereto.

[0016] In this embodiment, these first optical microstructures OMS1 are provided so as to correspond to the first light source LS1, and these second optical microstructures OMS2 are provided so as to correspond to the second light source LS2. More specifically, each of the plurality of first optical microstructures OMS1 has a first patterned reflecting surface PRS1 facing the first light source LS1, and a first off-axis reflecting surface ORS1 facing the second light source LS2. For example, each of the plurality of second optical microstructures OMS2 has a second patterned reflecting surface PRS2 facing the second light source LS2, and a second off-axis reflecting surface ORS2 facing the first light source LS1. The first patterned reflecting surface PRS1 forms a first patterned reflection angle PA1 with a virtual extended surface VES of the bottom surface BS. The first off-axis reflecting surface ORS1 forms a first off-axis reflection angle OA1 with the virtual extended surface VES of the bottom surface BS. The second patterned reflecting surface PRS2 forms a second patterned reflection angle PA2 with the virtual extended surface VES of the bottom surface BS. The second off-axis reflecting surface ORS2 forms a second off-axis reflection angle OA2 with the virtual extended surface VES of the bottom surface BS.

[0017] Furthermore, the first pattern reflection angle PA1 of the first optical microstructure OMS1 is greater than the first off-axis reflection angle OA1, and the second pattern reflection angle PA2 of the second optical microstructure OMS2 is greater than the second off-axis reflection angle OA2. More specifically, both the first pattern reflection angle PA1 and the second pattern reflection angle PA2 are 25 degrees or more and 60 degrees or less, and both the first off-axis reflection angle OA1 and the second off-axis reflection angle OA2 are 10 degrees or more and 20 degrees or less.

[0018] For example, the first light source LS1 emits a ray L1a (i.e., the first ray) toward the first patterned reflective surface PRS1 of any first optical microstructure OMS1, and emits a ray L1b (i.e., the second ray) toward the second off-axis reflective surface ORS2 of any second optical microstructure OMS2. The second light source LS2 emits a ray L2a (i.e., the third ray) toward the second patterned reflective surface PRS2 of any second optical microstructure OMS2, and emits a ray L2b (i.e., the fourth ray) toward the first off-axis reflective surface ORS1 of any first optical microstructure OMS1.

[0019] The light ray L1a reflected via the first pattern reflective surface PRS1 is emitted from the light-emitting surface ES at a first emission angle θ1. The light ray L1b reflected via the second off-axis reflective surface ORS2 is emitted from the light-emitting surface ES at a second emission angle θ2. The light ray L2a reflected via the second pattern reflective surface PRS2 is emitted from the light-emitting surface ES at a third emission angle θ3. The light ray L2b reflected via the first off-axis reflective surface ORS1 is emitted from the light-emitting surface ES at a fourth emission angle θ4. Here, the light-emitting surface ES of the light guide plate LGP connects the first light-ingress surface IS1 and the second light-ingress surface IS2 and faces the bottom surface BS. The emission angle is, for example, the angle between the light ray and the normal direction of the light-emitting surface ES (for example, direction Z).

[0020] Furthermore, by limiting the angular range of the pattern reflection angle and off-axis reflection angle of the optical microstructure described above, the second emission angle θ2 of ray L1b is clearly larger than the first emission angle θ1 of ray L1a, and the fourth emission angle θ4 of ray L2b is clearly larger than the third emission angle θ3 of ray L2a. More specifically, when a ray (e.g., ray L1a) emitted by the first light source LS1 is incident on the first pattern reflection surface PRS1 of the first optical microstructure OMS1, it is reflected by the first pattern reflection surface PRS1 within the observation range of the user USR (e.g., the field of view range of the left eye LEYE). When a ray emitted by the first light source LS1 (e.g., ray L1b) is incident on the second off-axis reflective surface ORS2 of the second optical microstructure OMS2, it is reflected by the second off-axis reflective surface ORS2 outside the observation range of the user USR (the second emission angle θ2 is, for example, greater than 45 degrees or greater than 60 degrees). Similarly, when a ray emitted by the second light source LS2 (e.g., ray L2a) is incident on the second pattern reflective surface PRS2 of the second optical microstructure OMS2, it is reflected by the second pattern reflective surface PRS2 within the observation range of the user USR (e.g., the field of view range of the right eye REYE). When a ray emitted by the second light source LS2 (e.g., ray L2b) is incident on the first off-axis reflective surface ORS1 of the first optical microstructure OMS1, it is reflected by the first off-axis reflective surface ORS1 outside the observation range of the user USR. In this way, it is possible to avoid the reflection of light rays emitted by a light source in the direction of the wrong field of view via the wrong optical microstructure.

[0021] In other words, the first optical microstructure OMS1 reflects the light ray L1a from the first light source LS1 in the direction of one eye of the user USR (e.g., the left eye LEYE) (e.g., the field of view corresponding to the first emission angle θ1 in Figures 2 and 3), while the second optical microstructure OMS2 reflects the light ray L2a from the second light source LS2 in the direction of the other eye of the user USR (e.g., the right eye LEYE) (e.g., the field of view corresponding to the third emission angle θ3 in Figures 2 and 3). As shown in Figure 3, when both the first light source LS1 and the second light source LS2 are enabled, the distribution of the normalized luminance of the light source module 10 in Figure 2 with respect to the viewing angle is substantially concentrated in the viewing angle range corresponding to the first emission angle θ1 of ray L1a (as shown in Figure 3, the first emission angle θ1 is 12 degrees and the full width at half maximum of the emitted range of ray L1a is 15 degrees) and the viewing angle range corresponding to the third emission angle θ3 of ray L2a (as shown in Figure 3, the third emission angle θ3 is -13 degrees and the full width at half maximum of the emitted range of ray L2a is 15 degrees).

[0022] That is, when the user USR is positioned in a predetermined location, one eye of the user USR can see the distribution pattern on the light guide plate LGP of the multiple second optical microstructures OMS2 by light rays L1a from each first optical microstructure OMS1, and the other eye of the user USR can see the distribution pattern on the light guide plate LGP of the multiple second optical microstructures OMS2 by light rays L2a from each second optical microstructure OMS2. Furthermore, depending on the design of the pattern reflective surface and off-axis reflective surface of the first optical microstructure OMS1 and the second optical microstructure OMS2, one eye of the user USR cannot clearly see the distribution pattern on the light guide plate LGP of the multiple second optical microstructures OMS2, and the other eye of the user USR cannot clearly see the distribution pattern on the light guide plate LGP of the multiple first optical microstructure OMS1.

[0023] To further explain, as shown in Figures 2, 4A, and 4B, for example, the orthographic distribution on the bottom surface BS of multiple first optical microstructures OMS1 can constitute a first field of view pattern PP1 (shown in Figure 4A), and the orthographic distribution on the bottom surface BS of multiple second optical microstructures OMS2 can constitute a second field of view pattern PP2 (shown in Figure 4B). In this embodiment, the first field of view pattern PP1 and the second field of view pattern PP2 may have parallax; that is, the first field of view pattern PP1 and the second field of view pattern PP2 are patterns of an object at different field of view angles. Therefore, when the first field of view pattern PP1 and the second field of view pattern PP2, which have parallax, are viewed by the right eye reye and left eye reye of the user USR, respectively, a stereoscopic image visual effect can be generated through fusion in the user USR's brain.

[0024] As shown in Figure 1, in this embodiment, the first pattern reflective surface PRS1 of each first optical microstructure OMS1 has a first edge OMS1e connected to the bottom surface BS. The central vertical line PB1 of the first edge OMS1e is perpendicular to the first light-receiving surface IS1 of the light guide plate LGP and passes through the first light source LS1. Similarly, the second pattern reflective surface PRS2 of each second optical microstructure OMS2 has a second edge OMS2e connected to the bottom surface BS. The central vertical line PB2 of the second edge OMS2e is perpendicular to the second light-receiving surface IS2 of the light guide plate LGP and passes through the second light source LS2.

[0025] In this embodiment, the first light source LS1 and the second light source LS2 are line light sources, and the central vertical line at the edge of the pattern reflection surface of each optical microstructure is perpendicular to the corresponding light-receiving surface. Therefore, the problem of low display brightness in conventional light source modules can be greatly improved, and the limitation on the size of the pattern displayed by the light source module can be avoided.

[0026] On the other hand, in this embodiment, as shown in Figure 5A, the first optical microstructure OMS1 and the second optical microstructure OMS2 are asymmetric elongated structures (an asymmetric structure means that the optical microstructure is asymmetrical because the angle of the pattern reflection angle and the angle of the off-axis reflection angle are different). However, the present invention is not limited thereto. In other modifications, the first optical microstructure OMS1-A and the second optical microstructure OMS2-A may be asymmetric long arc-shaped structures (shown in Figure 5B) in order to diffuse the light rays in a direction perpendicular to the central vertical line PB1 or the central vertical line PB2. Here, the central vertical lines of the first edge OMS1e-A of the first pattern reflection surface PRS1-A of the first optical microstructure OMS1-A and the second edge OMS2e-A of the second pattern reflection surface PRS2-A of the second optical microstructure OMS2-A are, for example, the central vertical line of the shortest connecting line between their two endpoints.

[0027] In other variations, the first optical microstructure OMS1-B and the second optical microstructure OMS2-B may be other forms of asymmetric long arc structures (shown in Figure 5C). Here, the central vertical line of the first edge OMS1e-B of the first pattern reflective surface PRS1-B of the first optical microstructure OMS1-B and the second edge OMS2e-B of the second pattern reflective surface PRS2-B of the second optical microstructure OMS2-B are, for example, the central vertical line of the shortest connecting line between their two endpoints. The only difference between the optical microstructure in Figure 5B and the optical microstructure in Figure 5C is the radius of curvature of the edges of the pattern reflective surfaces; for example, the radii of curvature of the first edge OMS1e-A and the second edge OMS2e-A in Figure 5B are greater than the radii of curvature of the first edge OMS1e-B and the second edge OMS2e-B in Figure 5C.

[0028] The present invention will be described in detail below by listing other embodiments. Note that the same symbols may be assigned to the same components, the same technical content may be omitted, and the omitted parts may be referred to the above embodiments; however, such explanations will be omitted below.

[0029] Figure 6 is a top view of a light source module according to a second embodiment of the present invention. Figure 7 is a cross-sectional view of the light source module of Figure 6. Figure 8A is a schematic diagram of a first viewing angle pattern formed by a plurality of first optical microstructures of Figure 6. Figure 8B is a schematic diagram of a second viewing angle pattern formed by a plurality of second optical microstructures of Figure 6. Figure 8C is a schematic diagram of a third viewing angle pattern formed by a plurality of third optical microstructures of Figure 6. Figure 8D is a schematic diagram of a fourth viewing angle pattern formed by a plurality of fourth optical microstructures of Figure 6.

[0030] As shown in Figures 6 and 7, compared with the light source module 10 in Figures 1 and 2, the light source module 11 according to this embodiment may further include a plurality of third optical microstructures OMS3 and a plurality of fourth optical microstructures OMS4 provided on the bottom surface BS of the light guide plate LGP-A. For example, the plurality of first optical microstructures OMS1, a plurality of second optical microstructures OMS2, a plurality of third optical microstructures OMS3 and a plurality of fourth optical microstructures OMS4 may be substantially arranged alternately along the normal direction (e.g., direction Y) of the first light receiving surface IS1 or the second light receiving surface IS2, but are not limited thereto. The arrangement of the plurality of first optical microstructures OMS1 and a plurality of second optical microstructures OMS2 according to this embodiment on the bottom surface BS is the same as the plurality of first optical microstructures OMS1 and a plurality of second optical microstructures OMS2 of the light source module 10 in Figure 2, so for a detailed explanation, refer to the relevant paragraphs of the above embodiment, and the explanation will be omitted here.

[0031] In this embodiment, a plurality of third optical microstructures OMS3 are provided to correspond to a first light source LS1, and a plurality of fourth optical microstructures OMS4 are provided to correspond to a second light source LS2. More specifically, each of the plurality of third optical microstructures OMS3 has a third pattern reflection surface PRS3 facing the first light source LS1 and a third off-axis reflection surface ORS3 facing the second light source LS2. Each of the plurality of fourth optical microstructures OMS4 has a fourth pattern reflection surface PRS4 facing the second light source LS2 and a fourth off-axis reflection surface ORS4 facing the first light source LS1. A third pattern reflection angle PA3 is provided between the third pattern reflection surface PRS3 and the virtual extending surface VES of the bottom surface BS. A third off-axis reflection angle OA3 is provided between the third off-axis reflection surface ORS3 and the virtual extending surface VES of the bottom surface BS. A fourth pattern reflection angle PA4 exists between the fourth pattern reflection surface PRS4 and the virtual extension surface VES of the base surface BS. A fourth off-axis reflection angle OA4 exists between the fourth off-axis reflection surface ORS4 and the virtual extension surface VES of the base surface BS.

[0032] Furthermore, the third pattern reflection angle PA3 of the third optical microstructure OMS3 is greater than the third off-axis reflection angle OA3, and the fourth pattern reflection angle PA4 of the fourth optical microstructure OMS4 is greater than the fourth off-axis reflection angle OA4. More specifically, both the third pattern reflection angle PA3 and the fourth pattern reflection angle PA4 are 25 degrees or more and 60 degrees or less, and both the third off-axis reflection angle OA3 and the fourth off-axis reflection angle OA4 are 10 degrees or more and 20 degrees or less.

[0033] For example, a first light source LS1 emits a ray L1c toward a third pattern reflective surface PRS3 of any third optical microstructure OMS3, and a second light source LS2 emits a ray L2c toward a fourth pattern reflective surface PRS4 of any fourth optical microstructure OMS4. The ray L1c reflected through the third pattern reflective surface PRS3 is emitted from the light-emitting surface ES at a fifth emission angle θ5. The ray L2c reflected through the fourth pattern reflective surface PRS4 is emitted from the light-emitting surface ES at a sixth emission angle θ6. The fifth emission angle θ5 may be greater than the first emission angle θ1, and the sixth emission angle θ6 may be greater than the third emission angle θ3.

[0034] The effects of the third off-axis reflective surface ORS3 of the third optical microstructure OMS3 and the fourth off-axis reflective surface ORS4 of the fourth optical microstructure OMS4 on rays from non-corresponding light sources are the same as the effects of the first off-axis reflective surface ORS1 of the first optical microstructure OMS1 and the second off-axis reflective surface ORS2 of the second optical microstructure OMS2 on rays from non-corresponding light sources. For a detailed explanation, please refer to the relevant paragraphs of the above embodiment, and such explanation will be omitted here.

[0035] In this embodiment, each of the third pattern reflective surfaces PRS3 of the multiple third optical microstructures OMS3 can reflect the light ray L1c from the first light source LS1 toward a first viewing angle. Each of the first pattern reflective surfaces PRS1 of the multiple first optical microstructures OMS1 can reflect the light ray L1a from the first light source LS1 toward a second viewing angle. Each of the second pattern reflective surfaces PRS2 of the multiple second optical microstructures OMS2 can reflect the light ray L2a from the second light source LS2 toward a third viewing angle. Each of the fourth pattern reflective surfaces PRS4 of the multiple fourth optical microstructures OMS4 can reflect the light ray L2c from the second light source LS2 toward a fourth viewing angle.

[0036] For example, the first, second, third, and fourth field angles described above may be arranged sequentially along the opposite direction of the Y direction in Figure 7, and the distance between the positions where the light beams (principal beams) of adjacent field angles are transmitted to a predetermined moving area of ​​the user USR is substantially equal to the pupillary distance of the user USR (the distance between the left eye LEYE and the right eye REYE of the user USR). In addition to the positions of both eyes shown in Figure 7, if the left eye LEYE of the user USR is in the first field angle (i.e., the left eye LEYE is located in the exit path of ray L1c), then its right eye REYE is in the second field angle (i.e., the right eye REYE is located in the exit path of ray L1a). If the user's left eye LEYE is in the third field of view (i.e., the left eye LEYE is located in the path of ray L2a), then their right eye LEYE is in the fourth field of view (i.e., the right eye LEYE is located in the path of ray L2c).

[0037] As shown in Figures 7 and 8A to 8D, for example, in this embodiment, the orthographic projection distribution on the bottom surface BS of a plurality of third optical microstructures OMS3 may constitute a first viewing angle pattern PP1 (shown in Figure 8A), the orthographic projection distribution on the bottom surface BS of a plurality of first optical microstructures OMS1 may constitute a second viewing angle pattern PP2 (shown in Figure 8B), the orthographic projection distribution on the bottom surface BS of a plurality of third optical microstructures OMS3 may constitute a third viewing angle pattern PP3 (shown in Figure 8C), and the orthographic projection distribution on the bottom surface BS of a plurality of fourth optical microstructures OMS4 may constitute a fourth viewing angle pattern PP4 (shown in Figure 8D). In this embodiment, the first field of view pattern PP1 corresponding to the fifth exit angle θ5 (i.e., the first field of view), the second field of view pattern PP2 corresponding to the first exit angle θ1 (i.e., the second field of view), the third field of view pattern PP3 corresponding to the third exit angle θ3 (i.e., the third field of view), and the fourth field of view pattern PP4 corresponding to the sixth exit angle θ6 (i.e., the fourth field of view) may have parallax with respect to each other, that is, the first field of view pattern PP1, the second field of view pattern PP2, the third field of view pattern PP3, and the fourth field of view pattern PP4 are patterns of a single object at different field of view angles. Therefore, when the first field of view pattern PP1 and the second field of view pattern PP2, the second field of view pattern PP2 and the third field of view pattern PP3, or the third field of view pattern PP3 and the fourth field of view pattern PP4, which have parallax, are viewed by the left eye LEYE and right eye LEYE of the user USR, respectively, a stereoscopic visual effect can be generated through fusion in the user USR's brain.

[0038] Figures 9A and 9B are cross-sectional views of a light source module according to a third embodiment of the present invention. Figure 10 is a cross-sectional view of a light source module according to a fourth embodiment of the present invention. As shown in Figures 9A and 9B, the main difference between the light source module 10A according to this embodiment and the light source module 10 in Figure 2 is the pattern composed of multiple optical microstructures. Specifically, in the light source module 10A according to this embodiment, the orthographic projection distribution on the bottom surface BS of the light guide plate LGP-B of the multiple first optical microstructures OMS1-C constitutes a first pattern, and the orthographic projection distribution on the bottom surface BS of the light guide plate LGP-B of the multiple second optical microstructures OMS2-C constitutes a second pattern, and the first pattern and the second pattern are identical. The first pattern and the second pattern are, for example, the patterns shown in Figure 4A or Figure 4B, but are not limited thereto.

[0039] In this embodiment, the first pattern reflective surface PRS1 of the first optical microstructure OMS1-C reflects the light ray L1 from the first light source LS1 to the user USR1, and the second pattern reflective surface PRS2 of the second optical microstructure OMS2-C reflects the light ray L2 from the second light source LS2 to the user USR2. Therefore, when both the first light source LS1 and the second light source LS2 are enabled, users USR1 and USR2 can see the same first and second patterns, respectively. In this case, the light source module 10A has a first viewing angle range.

[0040] When the first light source LS1 is enabled and the second light source LS2 is disabled, user USR1 can see the first pattern, but user USR2 cannot see the second pattern. In other words, only user USR1 can see the pattern displayed on the light guide plate LGP-B. To put it another way, in this case, the light source module 10A has a second viewing angle range, and the first viewing angle range is larger than the second viewing angle range. Therefore, the light source module 10A according to this embodiment can adjust the angle range of light emission by turning the first light source LS1 and the second light source LS2 on or off.

[0041] However, the present invention is not limited thereto. As shown in Figure 10, in a light source module 11A according to another embodiment, the light guide plate LGP-C may be further provided with a plurality of third optical microstructures OMS3-C and a plurality of fourth optical microstructures OMS4-C. The orthographic projection distribution of the plurality of third optical microstructures OMS3-C on the bottom surface BS of the light guide plate LGP-B constitutes a third pattern, and the orthographic projection distribution of the plurality of fourth optical microstructures OMS4-C on the bottom surface BS of the light guide plate LGP-B constitutes a fourth pattern, and the first pattern, second pattern, third pattern and fourth pattern are identical to each other. The above-mentioned first to fourth patterns are, for example, the patterns shown in Figure 4A or Figure 4B, but are not limited thereto.

[0042] In this embodiment, the third pattern reflective surface PRS3 of the third optical microstructure OMS3-C reflects the light ray L1 from the first light source LS1 to the user USR3, and the fourth pattern reflective surface PRS4 of the fourth optical microstructure OMS4-C reflects the light ray L2 from the second light source LS2 to the user USR4. Therefore, when both the first light source LS1 and the second light source LS2 are enabled, users USR1, USR2, USR3, and USR4 can see the same first, second, third, and fourth patterns, respectively. In this case, the light source module 11A has a third viewing angle range, which is larger than the first viewing angle range of the light source module 10A in Figure 9A.

[0043] When the first light source LS1 is enabled and the second light source LS2 is disabled, users USR1 and USR3 can see the same first and third patterns, respectively, but users USR2 and USR4 cannot see the second and fourth patterns. In this case, the light source module 11A has a fourth viewing angle range, and this fourth viewing angle range is larger than the second viewing angle range of the light source module 10A in Figure 9B.

[0044] In other words, the plurality of third optical microstructures OMS3-C and plurality of fourth optical microstructures OMS4-C additionally provided on the light guide plate LGP-C according to this embodiment can further increase the angle range of light output from the light source module 11A when the first light source LS1 and / or the second light source LS2 are activated.

[0045] As described above, in a light source module according to one embodiment of the present invention, the first light source and the second light source are provided so as to correspond to two opposing light-receiving surfaces of the light guide plate, and the bottom surface of the light guide plate is provided with a plurality of first optical microstructures corresponding to the first light source and a plurality of second optical microstructures corresponding to the second light source. Since the angle of the patterned reflective surface of each optical microstructure facing the corresponding light source with respect to the bottom surface is greater than the angle of the off-axis reflective surface facing the non-corresponding light source with respect to the bottom surface, the patterned reflective surface of the optical microstructure can guide the light rays emitted by the corresponding light source to the required viewing angle, and the off-axis reflective surface can guide the light rays emitted by the non-corresponding light source outside the required viewing angle. According to the corresponding arrangement relationship of the two sets of light sources and optical microstructures described above, the light source module can have a stereoscopic image display function or a switchable light emission angle range.

[0046] The above description is merely a preferred embodiment of the present invention, and the scope of implementation of the present invention is not limited thereto. Any modifications and modifications are possible by those skilled in the art based on the claims and specification of the present invention, and the scope of protection of the present invention is based on the claims. Furthermore, none of the embodiments or claims of the present invention necessarily have to realize all of the purposes, advantages, or features disclosed by the present invention. Also, the abstract and title (title of the invention) are merely for assisting in the search of patent documents and do not limit the scope of rights of the present invention. In addition, terms such as "first," "second," etc. in this specification or the claims are merely for naming elements or distinguishing different embodiments or scopes, and do not limit the upper or lower number of components. [Explanation of Symbols]

[0047] 10, 11, 10A, 11A: Light source modules BS: Bottom ES:Idemitsu surface IS1: First light-receiving surface IS2: Second light-receiving surface L1, L2, L1a, L1b, L1c, L2a, L2b, L2c: Ray LEYE: Left eye LGP, LGP-A, LGP-B, LGP-C: Light guide plate LS1: First light source LS2: Second light source OA1~OA4: First off-axis reflection angle ~ Fourth off-axis reflection angle OMS1, OMS1-A, OMS1-B, OMS1-C: First optical microstructure OMS1e, OMS1e-A, OMS1e-B: First edge OMS2, OMS2-A, OMS2-B, OMS2-C: Second Optical Microstructure OMS2e, OMS2e-A, OMS2e-B: Second edge OMS3, OMS3-C: Third Optical Microstructure OMS4, OMS4-C: Fourth Optical Microstructure ORS1~ORS4: First off-axis reflective surface~Fourth off-axis reflective surface PA1~PA4: First pattern reflection angle ~ Fourth pattern reflection angle PB1, PB2: Center vertical line PRS1, PRS1-A, PRS1-B: First patterned reflective surface PRS2, PRS2-A, PRS2-B: Second patterned reflective surface PRS3: Third pattern reflective surface PRS4: Fourth pattern reflective surface PP1~PP4: First field of view pattern to fourth field of view pattern REYE:Right eye USR, USR1~USR4: User VES: Virtual extended surface X, Y, Z: direction θ1~θ6: First launch angle to sixth launch angle

Claims

1. A light source module comprising a light guide plate, a first light source, a second light source, a plurality of first optical microstructures, and a plurality of second optical microstructures, The light guide plate has a bottom surface and a first light-receiving surface and a second light-receiving surface connected to the bottom surface and facing each other. The first light source is provided on the first light-receiving surface side of the light guide plate, The second light source is provided on the second light-receiving surface side of the light guide plate, The plurality of first optical microstructures are provided on the bottom surface of the light guide plate and each has a first pattern reflective surface facing the first light source and a first off-axis reflective surface facing the second light source, and each has a first pattern reflection angle between the first pattern reflective surface and the virtual extending surface of the bottom surface, and a first off-axis reflection angle between the first off-axis reflective surface and the virtual extending surface of the bottom surface, The plurality of second optical microstructures are provided on the bottom surface of the light guide plate and each has a second pattern reflective surface facing the second light source and a second off-axis reflective surface facing the first light source, and each has a second pattern reflection angle between the second pattern reflective surface and the virtual extending surface of the bottom surface, and a second off-axis reflection angle between the second off-axis reflective surface and the virtual extending surface of the bottom surface, The first pattern reflection angle and the second pattern reflection angle are 25 degrees or more and 60 degrees or less. A light source module characterized in that the first off-axis reflection angle and the second off-axis reflection angle are 10 degrees or more and 20 degrees or less.

2. The light source module further includes a plurality of third optical microstructures, The plurality of third optical microstructures are provided on the bottom surface of the light guide plate and each has a third pattern reflective surface facing the first light source and a third off-axis reflective surface facing the second light source, and each has a third pattern reflection angle between the third pattern reflective surface and the virtual extending surface of the bottom surface, and a third off-axis reflection angle between the third off-axis reflective surface and the virtual extending surface of the bottom surface. The third pattern reflection angle is greater than the third off-axis reflection angle. The light source module according to claim 1, characterized in that the third pattern reflection angle is different from the first pattern reflection angle of each of the plurality of first optical microstructures.

3. The light source module further includes a plurality of fourth optical microstructures, The plurality of fourth optical microstructures are provided on the bottom surface of the light guide plate and each has a fourth pattern reflective surface facing the second light source and a fourth off-axis reflective surface facing the first light source, and there is a fourth pattern reflection angle between the fourth pattern reflective surface and the virtual extending surface of the bottom surface, and there is a fourth off-axis reflection angle between the fourth off-axis reflective surface and the virtual extending surface of the bottom surface, The fourth pattern reflection angle is greater than the fourth off-axis reflection angle. The light source module according to claim 2, characterized in that the fourth pattern reflection angle is different from the second pattern reflection angle of each of the plurality of second optical microstructures.

4. The third pattern reflection angle and the fourth pattern reflection angle are 25 degrees or more and 60 degrees or less. The light source module according to claim 3, characterized in that the third off-axis reflection angle and the fourth off-axis reflection angle are 10 degrees or more and 20 degrees or less.

5. The light guide plate further has a light-emitting surface relative to the bottom surface, The first light source emits a first ray toward the first patterned reflective surface of the plurality of first optical microstructures, and emits a second ray toward the second off-axis reflective surface of the plurality of second optical microstructures. The second light source emits a third ray toward the second patterned reflective surface of the plurality of second optical microstructures, and emits a fourth ray toward the first off-axis reflective surface of the plurality of first optical microstructures. The first ray reflected through the first patterned reflective surface is emitted from the light-emitting surface at a first emission angle. The second ray reflected through the second off-axis reflecting surface is emitted from the light-emitting surface at a second emission angle. The third ray reflected through the second patterned reflective surface is emitted from the light-emitting surface at a third emission angle. The fourth ray reflected through the first off-axis reflecting surface is emitted from the light-emitting surface at a fourth emission angle. The second launch angle is greater than the first launch angle. The light source module according to claim 1, characterized in that the fourth emission angle is greater than the third emission angle.

6. Each of the first pattern reflective surfaces has a first edge that connects to the bottom surface, Each of the second pattern reflective surfaces has a second edge that connects to the bottom surface, The central vertical line of the first edge is perpendicular to the first light-receiving surface and passes through the first light source. The light source module according to claim 1, characterized in that the central vertical line of the second edge is perpendicular to the second light-receiving surface and passes through the second light source.

7. The orthographic projection distribution on the bottom surface of the plurality of first optical microstructures constitutes a first viewing angle pattern. The orthographic projection distribution on the bottom surface of the plurality of second optical microstructures constitutes a second viewing angle pattern. The light source module according to claim 1, characterized in that the first viewing angle pattern and the second viewing angle pattern have parallax.

8. The orthographic projection distribution on the bottom surface of the plurality of first optical microstructures constitutes a first pattern. The orthographic projection distribution on the bottom surface of the plurality of second optical microstructures constitutes a second pattern. The light source module according to claim 1, characterized in that the first pattern and the second pattern are identical.

9. When both the first light source and the second light source are enabled, the light source module has a first viewing angle range, When the first light source is enabled and the second light source is disabled, the light source module has a second viewing angle range. The light source module according to claim 8, characterized in that the first viewing angle range is greater than the second viewing angle range.

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