Light guide plate and light source device

Abstract

To provide a light guide plate and a light source device.SOLUTION: A light guide plate guides a plurality of light beams, and has a light incident plane and a first surface. The first surface is connected to the light incident plane. The light guide plate has a first region and a second region on the first surface. The first region is more approximate to the light incident plane than the second region. A plurality of first microstructures are arranged in the first region. Each of the first microstructures has a first curvature, and has crescent-shaped microstructure having a first ridge line, and the first curvature is a curvature of the first ridge line. A plurality of second microstructures are arranged in the second region. Each of the second microstructures has a second curvature, and the maximum value of the plurality of first curvatures is larger than maximum value of the plurality of second curvatures.SELECTED DRAWING: Figure 2A

Description

[Technical Field]

[0001] The present invention relates to an optical element and an optical device, and more particularly to a light guide plate and a light source device. [Background technology]

[0002] Current light source devices can be mainly divided into sidelight type light source devices and direct type light source devices. Sidelight type light source devices use a light guide plate to guide light from a light source arranged on the light input side of the light guide plate to the light output side of the light guide plate, thereby forming a surface light source. Generally, to form a lighting device with a patterned lighting effect, an optical microstructure for displaying a specific pattern may be formed on the surface of the light guide plate.

[0003] However, since the light source used in the light source device is a plurality of point light sources (e.g., LEDs), the optical microstructure is a linear rod-shaped microstructure, which reflects only vertically incident light, so the light from the light source has high directionality even after being reflected by the optical microstructure. Therefore, hot spots are likely to occur depending on the distance between the point light sources, affecting the image quality of the illumination pattern.

[0004] On the other hand, when performing local dimming of a lighting device, i.e., controlling the brightness difference between different regions on the surface of a light guide plate by controlling the brightness of different point light sources, the linear bar-shaped microstructures only reflect vertically incident light, so when more linear bar-shaped microstructures are provided on the surface of the light guide plate, the brightness difference between different regions on the surface of the light guide plate becomes more obvious. Therefore, the linear bar-shaped microstructures can improve the local dimming ability of the lighting device. Therefore, achieving both the local dimming ability of the lighting device and the image quality of the lighting pattern is actually a problem that related engineers need to consider and solve.

[0005] The contents of the "Background" section are intended to aid in understanding the present invention, and the contents of the "Background" section may include prior art other than that known to a person of ordinary skill in the art. The contents of the "Background" section, or those representative of the problems that one or more embodiments of the present invention attempt to solve, are not already known or recognized by a person of ordinary skill in the art prior to the filing of the present invention. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention provides a light guide plate that can improve the local dimming ability of a light source device and reduce the hot spot phenomenon.

[0007] The present invention provides a light source device that has good local dimming capability and can clearly switch between different optical patterns to display them.

[0008] Other objects and advantages of the present invention will become more apparent from the technical features disclosed in the present invention. [Means for solving the problem]

[0009] In order to achieve one, some, or all of the above-mentioned objects, or other objects, an embodiment of the present invention provides a light guide plate for guiding multiple light rays, the light guide plate having a light incident surface and a first surface, the first surface being connected to the light incident surface, the light guide plate having a first region and a second region on the first surface, the first region being closer to the light incident surface than the second region, the first region being provided with a plurality of first microstructures, each of the first microstructures having a first curvature, the first microstructures being crescent-shaped microstructures having a first ridge, the first curvature being the curvature of the first ridge, the second region being provided with a plurality of second microstructures, each of the second microstructures having a second curvature, and the maximum value of the plurality of first curvatures being greater than the maximum value of the plurality of second curvatures.

[0010] To achieve one, some, or all of the above-mentioned objects, or other objects, an embodiment of the present invention provides a light source device including a light source that provides a plurality of light beams and the above-mentioned light guide plate, wherein the light beams exhibit a predetermined pattern after leaving the light guide plate due to the first microstructure and the second microstructure.

[0011] In one embodiment of the present invention, the light source includes a plurality of light-emitting elements, the light rays have an optical axis direction, and an extending line extending from a midpoint position between adjacent light-emitting elements along a direction parallel to the optical axis direction defines an illumination effect area of ​​each of the light-emitting elements.

[0012] In one embodiment of the present invention, each of the first microstructures has a first optical surface and a third optical surface, the first optical surface facing the light incident surface and the third optical surface facing the opposite side of the light incident surface, and the first optical surface and the third optical surface of each of the first microstructures are connected to each other to form the first ridge line.

[0013] In one embodiment of the present invention, the plurality of first curvatures of the plurality of first microstructures gradually decrease from a side closer to the light incident surface toward a side farther from the light incident surface.

[0014] In one embodiment of the present invention, each of the second microstructures is a crescent-shaped microstructure, having a second optical surface and a fourth optical surface, the second optical surface facing the light incident surface, and the fourth optical surface facing the opposite side of the light incident surface, the second optical surface and the fourth optical surface of each of the second microstructures are connected to each other to form a second ridge line, the second curvature is the curvature of the second ridge line, and the multiple second curvatures of the multiple second microstructures gradually decrease from the side closer to the light incident surface to the side away from the light incident surface.

[0015] In one embodiment of the present invention, the first curvature is a fixed value.

[0016] In one embodiment of the present invention, the light guide plate further has a first side surface, the first side surface faces the light incident surface, the first surface is connected to the light incident surface and the first side surface, the light guide plate has a center line on the first surface, the distance between the light incident surface and the center line is equal to the distance between the first side surface and the center line, the first surface of the light guide plate forms the first region between the light incident surface and the center line, and the first surface of the light guide plate forms the second region between the first side surface and the center line. a region, each of the second microstructures being a rod-shaped microstructure, the second curvature being zero, the first region further comprising a plurality of the second microstructures, the number ratio of the second microstructures in the first region being smaller than the number ratio of the first microstructures in the first region, and the second region further comprising a plurality of the first microstructures, the number ratio of the second microstructures in the second region being greater than the number ratio of the first microstructures in the second region.

[0017] In one embodiment of the present invention, the plurality of light rays enter the light guide plate from the light incident surface and extend along an emission angle to form a plurality of illumination areas on the first surface, each of the illumination areas including a first sub-illumination area and a second sub-illumination area, the first sub-illumination area being an area of ​​each of the illumination areas that does not overlap with other illumination areas, the second sub-illumination areas being areas of adjacent illumination areas that overlap with each other, the first sub-illumination area being the first area, and the second sub-illumination area being the second area.

[0018] In one embodiment of the present invention, each of the second microstructures is a rod-shaped microstructure, the second curvature is zero, and the first sub-illumination region is further provided with a plurality of the second microstructures.

[0019] In one embodiment of the present invention, the second sub-illumination area is further provided with a plurality of the first microstructures, and the ratio of the number of the second microstructures in the second sub-illumination area is greater than the ratio of the number of the first microstructures in the second sub-illumination area.

[0020] In one embodiment of the present invention, the first microstructure is provided only in the first sub-illumination region.

[0021] In one embodiment of the invention, the first microstructure and the second microstructure are recessed into the first surface.

[0022] In one embodiment of the present invention, the light emitting device further includes a plurality of condenser lenses provided corresponding to the plurality of light emitting elements, respectively. [Effects of the Invention]

[0023] As described above, the embodiments of the present invention have at least one of the following advantages or effects. In the embodiments of the present invention, the first microstructures closer to the light incident side are crescent-shaped, which can reflect light rays over a wider range of angles, thereby effectively eliminating the hot spot phenomenon. Meanwhile, in the embodiments, the second microstructures further away from the light incident side are crescent-shaped with a relatively small curvature or rod-shaped with a curvature equal to zero, which limits the incident light reflected thereby to light incident from near the vertical direction. As a result, the second microstructures located in the illumination action area of ​​each light-emitting element do not reflect light rays from adjacent illumination action areas, thereby improving the local dimming capability of the light source device. As a result, the configuration of the first and second microstructures enables the light guide plate and the light source device to achieve local dimming capability and maintain the image quality of the illumination pattern.

[0024] In order to make the above features and advantages of the present invention more clearly apparent, the following detailed description of the embodiments will be given with reference to the accompanying drawings. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a schematic diagram illustrating the configuration of a light source device according to one embodiment of the present invention. [Figure 2A] FIG. 2 is a schematic diagram of a part of the configuration of the light source device of FIG. [Figure 2B] FIG. 2B is a schematic diagram of the microstructure configuration of FIG. 2A. [Figure 2C] FIG. 2B is a schematic diagram of a luminance simulation of the light source device of FIG. 2A. [Figure 2D] FIG. 10 is a schematic diagram illustrating a luminance simulation of a light source device according to a comparative example of the present invention. [Figure 3] FIG. 10 is a schematic diagram of a portion of the configuration of a light source device according to another embodiment of the present invention. [Figure 4] FIG. 10 is a schematic diagram of a portion of the configuration of a light source device according to another embodiment of the present invention. [Figure 5] FIG. 10 is a schematic diagram of a portion of the configuration of a light source device according to another embodiment of the present invention. [Figure 6] FIG. 10 is a schematic diagram of a portion of the configuration of a light source device according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0026] The above and other technical contents, features, and advantages of the present invention will be apparent from the detailed description of preferred embodiments with reference to the following drawings. Directional terms such as "upper," "lower," "left," "right," "front," and "rear" used in the following embodiments are merely descriptive terms referring to directions when referring to the drawings, and the present invention is not limited to those indicated by the directional terms.

[0027] FIG. 1 is a schematic diagram of a light source device according to one embodiment of the present invention. As shown in FIG. 1, the light source device 200 according to this embodiment includes a light guide plate 100, a first light source 210, and a second light source 220. For example, in this embodiment, the first light source 210 and the second light source 220 may be light bars including a plurality of light-emitting elements LE, and are used to provide a plurality of light beams. Here, the light-emitting elements LE are, for example, light-emitting diode (LED) elements or other types of light-emitting elements. For example, in this embodiment, the light guide plate 100 is used to guide the light beams, and the light guide plate 100 includes a plurality of microstructures (not shown) for displaying a first pattern and a plurality of microstructures (not shown) for displaying a second pattern. Furthermore, in this embodiment, the microstructures for displaying the first pattern extend along a first direction D1, the microstructures for displaying the second pattern extend along a second direction D2, and the normal direction of the light guide plate 100 is defined as a third direction D3. In this way, when the light source device 200 switches the first light source 210 to the on state and the second light source 220 to the off state, the light source device 200 displays the first pattern. When the light source device 200 switches the second light source 220 to the on state and the first light source 210 to the off state, the light source device 200 displays the second pattern.

[0028] More specifically, as shown in FIG. 1 , the light guide plate 100 has a first light incident surface SI1, a second light incident surface SI2, and a first surface S1. Here, the first light incident surface SI1 is adjacent to the second light incident surface SI2, and the first surface S1 is connected to the first light incident surface SI1 and the second light incident surface SI2. The plurality of microstructures for displaying the first pattern and the plurality of microstructures for displaying the second pattern are all located on the first surface S1. For example, in this embodiment, the first surface S1 is, for example, the bottom surface of the light guide plate 100. In other words, as shown in FIG. 2A , in this embodiment, the plurality of microstructures for displaying the first pattern and the plurality of microstructures for displaying the second pattern are all located on the bottom surface of the light guide plate 100. However, the present invention is not limited thereto. In other embodiments, the first surface S1 may be the top surface of the light guide plate 100, i.e., the plurality of microstructures for displaying the first pattern and the plurality of microstructures for displaying the second pattern may be located on the top surface of the light guide plate 100.

[0029] The structure of the light guide plate 100 for achieving the local dimming capability when the light source device 200 displays the first pattern will be further described below with reference to FIGS. 2A and 2B . Although the microstructures for displaying the first pattern and the microstructures for displaying the second pattern extend in different directions on the first surface S1 of the light guide plate 100, the microstructures for displaying the first pattern and the microstructures for displaying the second pattern may be considered to have the same optical design limitations. Therefore, for ease of explanation, the following will only describe the arrangement of the microstructures for displaying the first pattern when the light source device 200 displays the first pattern. Those skilled in the art may similarly arrange the microstructures for displaying the second pattern by referring to the arrangement of the microstructures to achieve the same effect, but this will not be described below.

[0030] 2A is a schematic diagram of a portion of the configuration of the light source device of FIG. 1. More specifically, FIG. 2A shows a light guide plate 100 (shown at a viewing angle from which the first surface S1 is visible) and a first light source 210 serving as a light source. FIG. 2B is a schematic diagram of the configuration of the microstructure of FIG. 2A. As shown in FIG. 2A, light rays emitted by the multiple light-emitting elements LE of the first light source 210 have an optical axis direction O, and an extension line E extending from the midpoint between adjacent light-emitting elements LE along a direction parallel to the optical axis direction O defines an illumination action area RIL of each light-emitting element LE. The light guide plate 100 has a first region R110 and a second region R120 on the first surface S1, and the first region R110 is closer to the first light incident surface SI1 than the second region R120. More specifically, in this embodiment, the light guide plate 100 further has a first side surface SS1, which faces the first light incident surface SI1, and the first surface S1 is connected to the first light incident surface SI1 and the first side surface SS1. The light guide plate 100 also has a center line M on the first surface S1, and the distance between the first light incident surface SI1 and the center line M is equal to the distance between the first side surface SS1 and the center line M. The first surface S1 of the light guide plate 100 forms a first region R110 between the first light incident surface SI1 and the center line M, and the first surface S1 of the light guide plate 100 forms a second region R120 between the first side surface SS1 and the center line M.

[0031] Specifically, in this embodiment, the light guide plate 100 has a first region R110 provided with a plurality of first microstructures 110, each of which has a first curvature. A second region R120 has a plurality of second microstructures 120, each of which has a second curvature. Specifically, the first microstructures 110 are crescent-shaped microstructures having a first ridge line SR1, and the first curvature is the curvature of the first ridge line SR1. For example, the first ridge line SR1 is a circular arc line. Each of the first microstructures 110 has a first optical surface OS1 and a third optical surface OS3, the first optical surface OS1 facing the first light incident surface SI1, the third optical surface OS3 facing the opposite side of the first light incident surface SI1, and the first optical surface OS1 and the third optical surface OS3 of each of the first microstructures 110 connecting to each other to form a first ridge line SR1. The multiple first curvatures of the multiple first microstructures 110 gradually decrease from the side closer to the first light incident surface SI1 toward the side farther from the first light incident surface SI1.

[0032] Meanwhile, the second microstructures 120 are also crescent-shaped microstructures having second ridge lines SR2, and the second curvature is the curvature of the second ridge lines SR2. The second ridge lines SR2 are arcuate lines. Each second microstructure 120 has a second optical surface OS2 and a fourth optical surface OS4, where the second optical surface OS2 faces the first light-incident surface SI1 and the fourth optical surface OS4 faces the opposite side from the first light-incident surface SI1. The second optical surface OS2 and the fourth optical surface OS4 of each second microstructure 120 are connected to each other to form the second ridge line SR2. The multiple second curvatures of the multiple second microstructures 120 gradually decrease from the side closer to the first light-incident surface SI1 toward the side farther from the first light-incident surface SI1.

[0033] In this embodiment, the maximum value of the plurality of first curvatures is greater than the maximum value of the plurality of second curvatures. Here, the magnitude of the curvature is the reciprocal of the radius of curvature passing through the ridge point. In other words, the smaller the curvature of the first ridge line SR1 or the second ridge line SR2 is, and the closer it is to zero, the closer the first ridge line SR1 or the second ridge line SR2 is to a straight line. Conversely, the greater the curvature of the first ridge line SR1 or the second ridge line SR2 is, the closer its edge is to a circular arc shape, which can be used to reflect light rays over a wider angular range. The first microstructure 110 and the second microstructure 120 are, for example, recessed into the first surface S1 of the light guide plate 100, but the present invention is not limited thereto. Meanwhile, the first microstructure 110 and the second microstructure 120 allow light rays to exhibit a predetermined pattern (e.g., a first pattern) after leaving the light guide plate 100. Specifically, these first microstructures 110 and these second microstructures 120 are arranged into a microstructure for displaying a first pattern, so that light rays passing through these first microstructures 110 and these second microstructures 120 represent the first pattern, and light representing the first pattern is emitted from the first optical surface OS1 of the first microstructure 110 and the second optical surface OS2 of the second microstructure 120.

[0034] As described above, in this embodiment, the first microstructure 110 near the light incident side is a crescent-shaped microstructure with a relatively large curvature. The curvature increases as the microstructure approaches the light incident side, allowing it to reflect light over a wider angular range and effectively eliminate hot spots. Meanwhile, in this embodiment, the second microstructure 120 farther from the light incident side is a crescent-shaped microstructure with a relatively small curvature. The curvature decreases as the microstructure moves away from the light incident side, resulting in an optical behavior similar to that of a rod-shaped microstructure. Therefore, the incident light reflected thereby is limited to light incident from near the vertical direction. Therefore, the second microstructure 120 located in the illumination action region RIL of each light-emitting element LE does not reflect light from adjacent illumination action regions RIL, thereby improving the local dimming capability of the light source device 200. Furthermore, when close to the light incident side, the light rays emitted by the light-emitting element LE corresponding to the adjacent lighting action area RIL do not diverge outside the lighting action area RIL, so even if the first microstructure 110 close to the light incident side is a crescent-shaped microstructure with a relatively large curvature, it does not affect the local dimming capability of the light source device 200.

[0035] Thus, the configuration of the first microstructure 110 and the second microstructure 120 allows the light source device 200 to achieve local dimming capabilities and maintain the image quality of the illumination pattern. More specifically, FIG. 2C is a schematic diagram of a luminance simulation of the light source device 200 of FIG. 2A. As shown in FIG. 2C, when the light-emitting element LE of the light source device 200 is turned on, the crescent-shaped microstructures with a relatively small curvature away from the light incident side of the light guide plate reduce the probability of reflecting light rays from adjacent illumination action areas RIL. In areas away from the light incident side of the light guide plate, the overlapping areas of light rays provided by adjacent light-emitting elements LE can be reduced, thereby improving the effect of local dimming. In contrast, FIG. 2D is a schematic diagram of a luminance simulation of a light source device according to a comparative example. In this light source device according to the comparative example, only crescent-shaped microstructures with a fixed curvature are arranged, and the crescent-shaped microstructures reflect the light rays provided by the light-emitting element LE. Here, the curvature of the microstructure used in the comparative example is the curvature of the microstructure closest to the light incident side of the light guide plate in the light source device 200 of Fig. 2A, i.e., the largest curvature among the multiple first curvatures of the multiple first microstructures 110. As shown in Fig. 2D, when the light emitting element LE of the light source device of Fig. 2D is turned on, the crescent-shaped microstructure with a fixed curvature used can reflect light rays in a wider angular range, so the local dimming effect in the area away from the light incident side of the light guide plate is less pronounced than in the case of Fig. 2C.

[0036] In the above embodiment, the first microstructure 110 and the second microstructure 120 are both crescent-shaped microstructures, but the present invention is not limited thereto. In other embodiments, the second microstructure 120 may be a rod-shaped microstructure. This will be further described below with reference to FIGS. 3 and 4.

[0037] FIG. 3 is a schematic diagram of a portion of the configuration of a light source device according to another embodiment of the present invention. As shown in FIG. 3, the light guide plate 300 and light source device 400 according to this embodiment are similar to the light guide plate 100 and light source device 200 of FIG. 2A, with the following differences: In this embodiment, the first microstructures 310 are crescent-shaped microstructures, the second microstructures 320 are rod-shaped microstructures, and the first curvature and the second curvature are fixed values. In other words, in this embodiment, the first curvature is greater than zero, and the second curvature is zero. Furthermore, the first region R110 may further include a plurality of second microstructures 320, and the second region R120 may further include a plurality of first microstructures 310. Furthermore, the ratio of the number of second microstructures 320 in the first region R110 is smaller than the ratio of the number of first microstructures 310 in the first region R110, and the ratio of the number of second microstructures 320 in the second region R120 is greater than the ratio of the number of first microstructures 310 in the second region R120.

[0038] As described above, in this embodiment, the ratio of the number of the first microstructures 310 in the first region R110 near the light incident side is greater than the ratio of the number of the second microstructures 320, so that most of the microstructures in the first region R110 can reflect light rays in a wider angular range, thereby effectively eliminating the hot spot phenomenon. On the other hand, in this embodiment, the ratio of the number of the second microstructures 320 in the second region R120 away from the light incident side is greater than the ratio of the number of the first microstructures 310, so that most of the incident light entering the second region R120 is still reflected by the second microstructures 320, and the second microstructures 320 only reflect incident light from the near vertical direction. As a result, the microstructures located in the illumination action region RIL of each light-emitting element LE do not reflect light rays from adjacent illumination action regions RIL, thereby improving the local dimming capability of the light source device 200. As a result, by configuring the first microstructure 310 and the second microstructure 320, the light guide plate 300 and the light source device 400 can realize local dimming capability, maintain the image quality of the illumination pattern, and achieve the same effects and advantages as the above-mentioned light guide plate 100 and the light source device 200, and the description thereof will be omitted here.

[0039] FIG. 4 is a schematic diagram of a portion of the configuration of a light source device according to another embodiment of the present invention. As shown in FIG. 4, a light guide plate 500 and a light source device 600 according to this embodiment are similar to the light guide plate 300 and the light source device 400 of FIG. 3, with the following differences: In this embodiment, the partitioning method of the first region R510 and the second region R520 of the light source device 600 is different from the partitioning method of the first region R110 and the second region R120 of the light source device 400 of FIG. 3. In this embodiment, multiple light rays enter the light guide plate 100 from the first light incident surface SI1 and extend along the emission angle to form multiple illumination regions IL on the first surface S1, respectively. Each illumination region IL includes a first sub-illumination region IL1 and a second sub-illumination region IL2. The first sub-illumination region IL1 is a region of each illumination region IL that does not overlap with other illumination regions IL, and the second sub-illumination region IL2 is a region of adjacent illumination regions IL that overlap with each other. The first sub-illumination region IL1 is the first region R510, and the second sub-illumination region IL2 is the second region R520. The first region R510 is closer to the first light incident surface SI1 than the second region R520. Furthermore, the extension line E passes through the end point of the second sub-illumination region IL2 on the side closest to the first light incident surface SI1. The first sub-illumination region IL1 is further provided with a plurality of second microstructures 320, with the proportion of the number of second microstructures 320 decreasing toward the light incident side.

[0040] As described above, since the first microstructures 310 are provided in the first region R510, the hot spot phenomenon can be effectively eliminated. In contrast, in this embodiment, since only the second microstructures 320 are provided in the second region R520, incident light from different light-emitting elements LE is reflected only by the second microstructures 320, and the second microstructures 320 reflect only incident light from the vertical direction. This prevents the microstructures located in the illumination action region RIL of each light-emitting element LE from reflecting light from adjacent illumination action regions RIL, thereby improving the local dimming capability of the light source device 600. Thus, by configuring the first microstructures 310 in the first region R510 and the second microstructures 320 in the second region R520, the light guide plate 500 and the light source device 600 can achieve local dimming capability, maintain the image quality of the illumination pattern, and achieve the same effects and advantages as the light guide plate 300 and the light source device 400 described above, and their description will be omitted here.

[0041] 4, in this embodiment, only the second microstructures 320 are provided in the second sub-illumination area IL2, i.e., the first microstructures 310 are provided only in the first sub-illumination area IL1, but the present invention is not limited thereto. In other embodiments not shown, the second sub-illumination area IL2 may further include a plurality of the first microstructures 310. The proportion of the number of the second microstructures 320 in the second sub-illumination area IL2 may be greater than the proportion of the number of the first microstructures 310 in the second sub-illumination area IL2. For example, the number of the second microstructures 320 may account for 70% to 100% of the total number of microstructures in the second sub-illumination area IL2, and the number of the first microstructures 310 may account for 0% to 30% of the total number of microstructures in the second sub-illumination area IL2.

[0042] In this way, as long as the number of the first microstructures 110 in the second sub-illumination region IL2 is within the above ratio range, the possibility that the first microstructures 110 reflect light rays from the adjacent illumination action region RIL can be reduced. Therefore, through the configuration of the first microstructures 110 and the second microstructures 120, the light guide plate 500 and the light source device 600 can achieve local dimming ability, maintain the image quality of the illumination pattern, and achieve the above-mentioned effects and advantages, which will not be described here.

[0043] 5 and 6 are schematic diagrams of portions of the configuration of two other light source devices according to the present invention. As shown in FIGS. 5 and 6, light source devices 200A and 200B according to these embodiments are similar to the light source device 200 of FIG. 2A, with the following differences: In the embodiments of FIGS. 5 and 6, the light source devices 200A and 200B further include a plurality of condenser lenses CL, each corresponding to a light-emitting element LE, positioned between the light-emitting element LE and the first region R110. More specifically, the condenser lenses CL may be independent elements and provided separately from the light guide plate 100 (see FIG. 6), or the condenser lenses CL and the light guide plate 100 may be integrated into an optical element (see FIG. 5). In this way, the configuration of the condenser lenses CL can converge the emission angle of the light beams provided by the light-emitting elements LE, thereby further improving the local dimming capability of the light source devices 200A and 200B. In addition, due to the configuration of the first microstructure 110 and the second microstructure 120, the light source devices 200A and 200B can achieve local dimming capability, maintain the image quality of the illumination pattern, and achieve effects and advantages similar to those of the light source device 200, and the description thereof will be omitted here.

[0044] As described above, the embodiments of the present invention have at least one of the following advantages or effects. In the embodiments of the present invention, the first microstructures closer to the light incident side are crescent-shaped, which can reflect light rays over a wider range of angles, thereby effectively eliminating the hot spot phenomenon. Meanwhile, in the embodiments of the present invention, the second microstructures further away from the light incident side are crescent-shaped with a relatively small curvature or rod-shaped with a curvature equal to zero, which limits the incident light reflected thereby to light incident from near the vertical direction. As a result, the second microstructures located in the illumination action area of ​​each light-emitting element do not reflect light rays from adjacent illumination action areas, thereby improving the local dimming capability of the light source device. The configuration of the first and second microstructures allows the light guide plate and the light source device to achieve local dimming capability and maintain the image quality of the illumination pattern.

[0045] The above description is merely a preferred embodiment of the present invention and does not limit the scope of the present invention. Any changes and modifications may be made by those skilled in the art based on the claims and the contents of the specification, and the scope of protection of the present invention is determined by the claims. Furthermore, neither the embodiments nor the claims of the present invention necessarily achieve all of the objectives, advantages, or features disclosed by the present invention. Furthermore, the abstract and the title of the invention are merely intended to aid in patent document searches and are not intended to limit the scope of the present invention. Furthermore, terms such as "first," "second," etc. in the specification or claims are merely intended to name elements or distinguish between different embodiments or scopes, and are not intended to limit the number of elements. [Explanation of symbols]

[0046] 100, 300, 500: Light guide plate 110, 310: First microstructure 120, 320: Secondary microstructure 200, 200A, 200B, 400, 600: Light source device 210: First light source 220: Second light source CL: Condenser lens D1: First direction D2: Second direction D3: The third direction E: Extension line IL: Lighting area IL1: First sub-illumination area IL2: Second sub-illumination area LE: Light-emitting element M: Center line O: Optical axis direction OS1: First optical surface OS2: Second Optical Surface OS3: Third Optical Surface OS4: Fourth Optical Surface R110, R510: First region R120, R520: Second region RIL: Lighting action area S1: First surface SI1: First light incident surface SI2: Second light incident surface SR1: First Ridge SR2: Second Ridge SS1: First Side

Claims

1. A light guide plate that guides multiple light rays from a first light source and a second light source, the light guide plate has a first light incident surface facing the first light source, a second light incident surface facing the second light source and having an extension direction different from that of the first light incident surface, and a first surface, the first surface being connected to the first light incident surface and the second light incident surface, the light guide plate having a first region, a second region, a third region, and a fourth region on the first surface, the first region being closer to the first light incident surface than the second region, and the third region being closer to the second light incident surface than the fourth region, the first region is provided with a plurality of first microstructures, each of the first microstructures having a first curvature, the first microstructures being crescent-shaped microstructures having a first ridge, the first curvature being a curvature of the first ridge; the second region is provided with a plurality of second microstructures, each of the second microstructures having a second curvature, and a maximum value of the plurality of first curvatures is greater than a maximum value of the plurality of second curvatures; the third region is provided with a plurality of third microstructures, each of the third microstructures having a third curvature, the third microstructures being crescent-shaped microstructures having a third ridge, the third curvature being a curvature of the third ridge; the fourth region is provided with a plurality of fourth microstructures, each of the fourth microstructures having a fourth curvature, and a maximum value of the plurality of third curvatures is greater than a maximum value of the plurality of fourth curvatures; a light guide plate in which the extending direction of the plurality of first microstructures is different from the extending direction of the plurality of third microstructures;

2. 2. The light guide plate according to claim 1, wherein each of the first microstructures has a first optical surface and a third optical surface, the first optical surface facing the first light incident surface, the third optical surface facing the opposite side of the first light incident surface, and the first optical surface and the third optical surface of each of the first microstructures connecting with each other to form the first ridge line.

3. The light guide plate according to claim 1 , wherein the plurality of first curvatures of the plurality of first microstructures gradually decrease from a side closer to the first light incident surface toward a side farther from the first light incident surface.

4. 4. The light guide plate of claim 3, wherein each of the second microstructures is a crescent-shaped microstructure and has a second optical surface and a fourth optical surface, the second optical surface faces the first light incident surface, the fourth optical surface faces the side opposite the first light incident surface, the second optical surface and the fourth optical surface of each of the second microstructures are connected to each other to form a second ridge line, the second curvature is a curvature of the second ridge line, and the second curvatures of the plurality of second microstructures gradually decrease from a side closer to the first light incident surface to a side away from the first light incident surface.

5. The light guide plate of claim 1 , wherein the first curvatures of the plurality of first microstructures are the same.

6. the light guide plate further has a first side surface, the first side surface facing the first light incident surface, the first surface connected to the first light incident surface and the first side surface, the light guide plate having a center line on the first surface, the distance between the first light incident surface and the center line being equal to the distance between the first side surface and the center line, the first surface of the light guide plate forming the first region between the first light incident surface and the center line, and the first surface of the light guide plate forming the second region between the first side surface and the center line; 6. The light guide plate of claim 5, wherein each of the second microstructures is a rod-shaped microstructure, the second curvature is zero, the first region further comprises a plurality of the second microstructures, the ratio of the number of the second microstructures in the first region being smaller than the ratio of the number of the first microstructures in the first region, and the second region further comprises a plurality of the first microstructures, the ratio of the number of the second microstructures in the second region being larger than the ratio of the number of the first microstructures in the second region.

7. 6. The light guide plate of claim 5, wherein the plurality of light rays enter the light guide plate from the first light incident surface and extend along an emission angle to form a plurality of illumination areas on the first surface, each of the illumination areas including a first sub-illumination area and a second sub-illumination area, the first sub-illumination area being an area of ​​each of the illumination areas that does not overlap with other illumination areas, the second sub-illumination areas being areas of adjacent illumination areas that overlap with each other, the first sub-illumination area being the first area, and the second sub-illumination area being the second area.

8. The light guide plate of claim 7 , wherein each of the second microstructures is a rod-shaped microstructure, the second curvature is zero, and the first sub-illumination region is further provided with a plurality of the second microstructures.

9. 8. The light guide plate of claim 7, wherein the second sub-illumination region further comprises a plurality of the first microstructures, and the ratio of the number of the second microstructures in the second sub-illumination region is greater than the ratio of the number of the first microstructures in the second sub-illumination region.

10. The light guide plate according to claim 7 , wherein the first microstructure is provided only in the first sub-illumination region.

11. The light guide plate of claim 1 , wherein the first microstructure and the second microstructure are recessed into the first surface.

12. a first light source and a second light source providing a plurality of light beams; a light guide plate for guiding the light beam, the light guide plate has a first light incident surface facing the first light source, a second light incident surface facing the second light source and having an extension direction different from that of the first light incident surface, and a first surface, the first surface being connected to the first light incident surface and the second light incident surface, the light guide plate having a first region, a second region, a third region, and a fourth region on the first surface, the first region being closer to the first light incident surface than the second region, and the third region being closer to the second light incident surface than the fourth region, the first region is provided with a plurality of first microstructures, each of the first microstructures having a first curvature, the first microstructures being crescent-shaped microstructures having a first ridge, the first curvature being a curvature of the first ridge; the second region is provided with a plurality of second microstructures, each of the second microstructures having a second curvature, and a maximum value of the plurality of first curvatures is greater than a maximum value of the plurality of second curvatures; the third region is provided with a plurality of third microstructures, each of the third microstructures having a third curvature, the third microstructures being crescent-shaped microstructures having a third ridge, the third curvature being a curvature of the third ridge; the fourth region is provided with a plurality of fourth microstructures, each of the fourth microstructures having a fourth curvature, and a maximum value of the plurality of third curvatures is greater than a maximum value of the plurality of fourth curvatures; an extension direction of the plurality of first microstructures and an extension direction of the plurality of third microstructures are different from each other; The light source device, wherein the light beam exhibits a predetermined pattern after leaving the light guide plate due to the first microstructure and the second microstructure.

13. The light source device according to claim 12, wherein the first light source and the second light source each include a plurality of light-emitting elements, the light rays have an optical axis direction, and an extension line extending from a midpoint position between adjacent light-emitting elements along a direction parallel to the optical axis direction defines an illumination effect area of ​​each light-emitting element.

14. 13. The light source device of claim 12, wherein each of the first microstructures has a first optical surface and a third optical surface, the first optical surface facing the first light incident surface, the third optical surface facing the opposite side of the first light incident surface, and the first optical surface and the third optical surface of each of the first microstructures connected to each other to form the first ridge line.

15. The light source device according to claim 12 , wherein the plurality of first curvatures of the plurality of first microstructures gradually decrease from a side closer to the first light incident surface toward a side farther from the first light incident surface.

16. 16. The light source device of claim 15, wherein each of the second microstructures is a crescent-shaped microstructure and has a second optical surface and a fourth optical surface, the second optical surface faces the first light incident surface, the fourth optical surface faces the opposite side of the first light incident surface, the second optical surface and the fourth optical surface of each of the second microstructures are connected to each other to form a second ridge line, the second curvature is the curvature of the second ridge line, and the multiple second curvatures of the multiple second microstructures gradually decrease from the side closer to the first light incident surface to the side away from the first light incident surface.

17. The light source device of claim 12 , wherein the first curvatures of the plurality of first microstructures are the same.

18. the light guide plate further has a first side surface, the first side surface facing the first light incident surface, the first surface connected to the first light incident surface and the first side surface, the light guide plate having a center line on the first surface, the distance between the first light incident surface and the center line being equal to the distance between the first side surface and the center line, the first surface of the light guide plate forming the first region between the first light incident surface and the center line, the first surface of the light guide plate forming the second region between the first side surface and the center line, 18. The light source device of claim 17, wherein each of the second microstructures is a rod-shaped microstructure, the second curvature is zero, the first region further comprises a plurality of the second microstructures, the ratio of the number of the second microstructures in the first region being smaller than the ratio of the number of the first microstructures in the first region, and the second region further comprises a plurality of the first microstructures, the ratio of the number of the second microstructures in the second region being larger than the ratio of the number of the first microstructures in the second region.

19. 18. The light source device of claim 17, wherein the plurality of light rays enter the light guide plate from the first light incident surface and extend along an emission angle to form a plurality of illumination areas on the first surface, each of the illumination areas including a first sub-illumination area and a second sub-illumination area, the first sub-illumination area being an area of ​​each of the illumination areas that does not overlap with other illumination areas, the second sub-illumination areas being areas of adjacent illumination areas that overlap with each other, the first sub-illumination area being the first area, and the second sub-illumination area being the second area.

20. 20. The light source device of claim 19, wherein each of the second microstructures is a rod-shaped microstructure, the second curvature is zero, and the first sub-illumination region is further provided with a plurality of the second microstructures.

21. 20. The light source device of claim 19, wherein the second sub-illumination area further includes a plurality of the first microstructures, and the ratio of the number of the second microstructures in the second sub-illumination area is greater than the ratio of the number of the first microstructures in the second sub-illumination area.

22. The light source device according to claim 19 , wherein the first microstructure is provided only in the first sub-illumination region.

23. The light source device of claim 12 , wherein the first microstructure and the second microstructure are recessed into the first surface.

24. The light source device according to claim 13 , further comprising a plurality of condenser lenses provided corresponding to the plurality of light-emitting elements, respectively.

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