Light source module and method for manufacturing light source module

Abstract

A light source module comprises a first light source, a second light source, a light guide and two freeform surface reflection elements. The light guide includes a light incident surface, a first reflection surface and a second reflection surface. The light incident surface allows the first light beam emitted by the first light source to pass through, and the first reflecting surface and the second reflection surface reflect the first light beam. The first light beam is transmitted along a first direction and a second direction respectively via the light guide to the two freeform surface reflective elements and the two freeform surface reflective elements reflect the first light beam to a projection surface. The second light source emits a second light beam, and the light guide is located between the first light source and the second light source. Two curved surfaces of the two freeform surface reflective elements are used to adjust the uniformity of an intensity of the first light beam on the projection surface. A method for manufacturing the light source module is also provided.

Description

Technical Field

[0001] This disclosure relates to a light source module and a method for manufacturing the light source module. Prior Technology

[0002] In the field of lighting, light source modules can be broadly divided into two categories. One category is projection light sources with optical elements that are used at long distances and have high light intensity and high transparency. The other category is decorative light sources with optical elements that are used at close distances and have high light uniformity and high haze.

[0003] However, these two types of light source modules are often difficult to design compatiblely. For example, projection light sources require high light output efficiency and light intensity to be concentrated and projected onto a distant projection surface, while decorative light sources often require good light uniformity and soft light to ensure the comfort of the observer at close range.

[0004] On the other hand, due to the rapid development of visual recognition and panoramic photography in recent years, the performance requirements of related optical lenses for the two types of light source modules have increased. For example, visual recognition requires long-distance projection of white light or far-infrared light, followed by detection and identification using a lens assembly. Panoramic photography lenses typically place multiple lens modules on top of a cylindrical structure. For aesthetic purposes, a ring-shaped decorative optical element is added to connect them into a single ring. Furthermore, to reduce costs and enhance aesthetics, these two types of light source modules are often placed on the same ring-shaped, coplanar circuit board (PCB), which presents the aforementioned physical conflicts. For example, the problem of light blocking between the two types of light source modules located on the same plane. Summary of the Invention

[0005] This disclosed embodiment provides a light source module, including a first light source, a second light source, a light guide, and two freeform surface reflective elements. The light guide includes an incident surface, a first reflecting surface, a second reflecting surface, a first emitting surface, and a second emitting surface. A first light beam enters the light guide from the incident surface and is reflected by the first and second reflecting surfaces, causing the first light beam to propagate through the first and second emitting surfaces in a first direction and a second direction, respectively. The first and second directions are different from each other. The two freeform surface reflective elements are respectively disposed on opposite sides of the light guide corresponding to the first and second emitting surfaces. The two freeform surface reflective elements are adapted to reflect the first light beam from the light guide to a projection surface. The second light source emits a second light beam, and the light guide is located between the first and second light sources in a third direction, which is different from the first and second directions. The two curved surfaces of the two freeform surface reflective elements are used to adjust the uniformity of the intensity of the first light beam on the projection surface.

[0006] The disclosed embodiments provide a method for manufacturing a light source module, which includes the above-mentioned light source module. The method includes the following steps: determining the angular range of the incident angle of a first beam on a projection surface and a plurality of first intensities corresponding to the angular range, to provide a first average value of the plurality of first intensities, and providing a plurality of first differences between each first intensity and the first average value. The method further involves determining the minimum value among the plurality of first differences and the corresponding first incident angle, defining the angular range as a first range and a second range, where the first range is from one end of the angular range to the first incident angle, and the second range is from the other end of the angular range to the first incident angle. The method also involves adjusting the curvature of the two surfaces of two freeform reflective elements to change a plurality of second intensities corresponding to the first beam in the first and second ranges, to determine a second average value of the plurality of second intensities in the first and second ranges, and a plurality of second differences between each second intensity and the second average value. Finally, the method involves determining the two minimum values ​​among the plurality of second differences in the first and second ranges and the corresponding two second incident angles.

[0007] Based on the above, in a light source module of this disclosure embodiment, a light guide is used to transmit the first beam of light provided by the first light source (which can be understood as the aforementioned decorative light source) in a third direction to the first direction and the second direction, respectively. Then, two freeform surface reflective elements are used to redirect the first beam of light, thus creating a space for the placement of the second light source (which can be understood as the aforementioned projection light source). Furthermore, the second light source does not obstruct the light field of the first beam of light emitted by the first light source. Therefore, the light source module can achieve compatibility with both light sources. In other words, the light source module of this disclosure embodiment can solve the physical limitation of mutual obstruction between the projection light source and the decorative light source when they are located on the same plane.

[0008] Furthermore, compared to the method of using haze elements to homogenize the first beam, this embodiment uses light guides and freeform surface reflection elements to provide the first beam, which can reduce light loss and replace the traditional approach of adjusting haze (sacrificing transmittance) to increase the uniformity of the projection surface brightness, effectively improving the light output efficiency and brightness of the light source module and enhancing the optical effect of the light source module.

[0009] Furthermore, the curved surfaces of the two freeform reflective elements can control the uniformity of the intensity of the first beam on the projection surface, thus effectively homogenizing the light field distribution of the first beam and enhancing product competitiveness.

[0010] To make the features and advantages disclosed herein more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings for detailed explanation. Simple Explanation of the Diagram

[0011] Figure 1A is a top view of a light source module according to an embodiment of the present disclosure. Figure 1B is a side view of the light source module in Figure 1A. Figure 1C is a three-dimensional schematic diagram of the light guide in Figure 1A. Figure 2 shows the relative intensity and angle relationship between the horizontal and vertical light fields of the first beam after it leaves the light guide in Figure 1A. Figures 3A to 3D are schematic diagrams of the surface design process of the two free-form surface reflective elements of the light source module in Figure 1A. Figures 4A and 4B are distribution diagrams of the horizontal and vertical light fields of the light source module in this embodiment of the present disclosure on the projection surface. Figure 5 is a side view of a light source module according to an embodiment of this disclosure. Figure 6 is a side view of a light source module according to an embodiment of this disclosure. Figure 7 is a partial structural schematic diagram of a light source module according to an embodiment of this disclosure. Figures 8A and 8B are schematic diagrams showing the arrangement of a light source module according to an embodiment of this disclosure. Implementation

[0012] As used herein, “about” or “substantially” includes the value and the average value within an acceptable range of deviations from the specific value as determined by one of ordinary skill in the art, taking into account the measurement under discussion and the specific number of errors associated with the measurement (i.e., limitations of the measurement system). Furthermore, the use of “about” or “substantially” herein may be chosen based on the nature of the measurement, the cutting nature, or other properties, and a single standard deviation may not be applicable to all properties.

[0013] The foregoing descriptions and other technical contents, features, and effects of this disclosure will be clearly presented in the following detailed description of a preferred embodiment with reference to the accompanying drawings. The directional terms mentioned in the following embodiments, such as up, down, left, right, front, or back, are merely for reference to the accompanying drawings. Therefore, the directional terms used are for illustrative purposes and not for limiting the scope of this disclosure.

[0014] Figure 1A is a top view of a light source module according to an embodiment of the present disclosure. Figure 1B is a side view of the light source module of Figure 1A. Figure 1C is a perspective view of the light guide in Figure 1A. Referring simultaneously to Figures 1A to 1C, the light source module 1A includes a first light source 11, a second light source 12, a light guide 20, a first freeform surface reflective element 30A, and a second freeform surface reflective element 30B. In direction D1, the light guide 20 is located between the first light source 11 and the second light source 12.

[0015] The light guide 20 includes an incident surface 21, a first reflecting surface 22A, a second reflecting surface 22B, a first emitting surface 23A, and a second emitting surface 23B. A first light beam L1 emitted from the first light source 11 enters the light guide 20 through the incident surface 21 and is reflected by the first reflecting surface 22A and the second reflecting surface 22B, causing the first light beam L1 to propagate towards directions D2 and D3 respectively through the first emitting surface 23A and the second emitting surface 23B. It is worth noting that, for ease of explanation of the emitting directions at various angles, directions X, Y, and Z can be three mutually perpendicular directions in a Cartesian coordinate system, while direction D1 can be substantially parallel to direction X, and directions D2 and D3 can be two different directions with direction D1 as the axis of symmetry. Furthermore, the vectors of the three directions D1, D2, and D3 can all lie in the same plane, and directions D1, D2, and D3 are all different from each other. In some embodiments, direction D2 may have an angle with direction Y, and direction D3 may also have the aforementioned angle with the opposite direction of direction Y, but this disclosure is not limited thereto. On the other hand, direction D4 may be substantially parallel to direction Z (and also perpendicular to the plane containing directions D1, D2 and D3), and represents the thickness direction of the light source module 1A.

[0016] In this embodiment, the first light source 11 can serve as a decorative light source. In some embodiments, the first light source 11 can be a light-emitting diode (LED) light source, a miniature LED light source, or an organic LED light source, and may include optical elements with refractive power (e.g., convex lenses, concave lenses, or freeform lenses) to control the divergence angle or light pattern distribution of the first beam L1 leaving the first light source 11. However, this disclosure is not limited to this. In this embodiment, the first light source 11 is a side-emitting LED light source and can have a large emission angle. For example, in direction D1, the emission angle of the first light source 11 can be approximately 120 degrees. In some embodiments, the wavelength of the first beam L1 emitted by the first light source 11 can be red light, green light, blue light, or wavelengths in other visible light bands. This disclosure is also not limited to this.

[0017] In this embodiment, the second light source 12 is used to emit a second light beam L2. The second light source 12 can serve as a projection light source. In some embodiments, the second light source 12 can be a light-emitting diode (LED) light source, a miniature LED light source, or an organic light-emitting diode (OLED) light source, and may also include optical elements with refractive power (e.g., convex lenses, concave lenses, or freeform lenses) to adjust the collimation and light distribution of the second light beam L2 emitted by the second light source 12, but this disclosure is not limited thereto. In some embodiments, the wavelength of the second light beam L2 emitted by the second light source 12 can be a continuous wavelength in the visible light band (e.g., white light), a near-infrared wavelength, or a far-infrared wavelength, but this disclosure is not limited thereto. In some embodiments, the second light source 12 can also serve as a sensing light source, for example, the second light source 12 can serve as a structured light source for three-dimensional sensing, but this disclosure is not limited thereto.

[0018] The light guide 20 is used to transmit and reflect the first light beam L1 within it. The substrate of the light guide 20 can be composed of a material with high transmittance, low absorptance, and low reflectance for the first light beam L1, such as glass or plastic, but is not limited thereto. Furthermore, the incident surface 21 can be a plane, and the normal vector of the plane can be substantially perpendicular to direction X (or direction D1). The light guide 20 can have an appropriate refractive index so that when the first light beam L1 emitted from the first light source 11 enters the optically denser medium (e.g., plastic) of the light guide 20 from the optically less dense medium (e.g., air) outside the light guide 20, the divergence angle of the first light beam L1 can be reduced, which is beneficial for the light collection of the light guide 20. On the other hand, in this embodiment, the first reflecting surface 22A and the second reflecting surface 22B are freeform surfaces, and are adapted to cause total internal reflection of the first light beam L1 within the light guide 20, but are not limited thereto.

[0019] On the other hand, in directions D2 and D3, the first freeform surface reflecting element 30A and the second freeform surface reflecting element 30B are respectively disposed on opposite sides of the light guide 20 to receive the first beam L1 from the light guide 20 and reflect the first beam L1 onto the first projection surface 40A. The first freeform surface reflecting element 30A and the second freeform surface reflecting element 30B respectively include a first curved surface 31A and a second curved surface 31B, used to adjust the uniformity of the intensity of the first beam L1 reflected onto the first projection surface 40A. The materials of the first freeform surface reflecting element 30A and the second freeform surface reflecting element 30B can be plastic or metal, and they are made by providing a reflective coating with high reflectivity for the first beam L1 on the first curved surface 31A and the second curved surface 31B, but this disclosure is not limited to this. The curvature design of the first curved surface 31A and the second curved surface 31B can be controlled and manufactured by optical simulation software, so that the first beam L1 can have better uniformity after being reflected by the first curved surface 31A and the second curved surface 31B (described later). The first projection surface 40A can have appropriate transmittance and haze for the first beam L1, so that the user can receive the first beam L1 on the side of the first projection surface 40A that is away from the second light source 12.

[0020] As described above, the light source module 1A, using the light guide 20, can adjust the optical path of the first beam L1 emitted by the first light source 11, allowing the first beam L1 to bypass the position of the second light source 12 and be transmitted to the light-emitting side, for example, to the first projection surface 40A. In other words, the light guide 20 can create a space for the second light source 12, and the second light source 12 will not block the light field of the first light source 11. This allows the light source module 1A to be compatible with two different light sources, solving the physical limitation of mutual occlusion between the projection light source and the decorative light source located on the same plane, and improving the versatility of the light source module 1A.

[0021] Furthermore, compared to the method of using haze elements to homogenize the decorative light source, this embodiment uses a light guide 20, a first freeform surface reflective element 30A, and a second freeform surface reflective element 30B to conduct the first beam L1. This avoids energy loss caused by the first beam L1 passing through the haze elements and also reduces the generation of stray light SL. By replacing the traditional approach of adjusting haze (sacrificing transmittance) to increase the uniformity of the projection surface brightness, this embodiment can effectively improve the light extraction efficiency and brightness of the light source module 1A and enhance the optical effect of the light source module 1A.

[0022] It is worth mentioning that the first light source 11, the second light source 12, the light guide 20, the first freeform surface reflective element 30A, and the second freeform surface reflective element 30B can be fixed or encapsulated together on the corresponding circuit board (not shown) using mechanical fasteners, adhesives, and electrical connection pins required by the light source (all not shown), which also improves the ease of manufacturing and assembly of the light source module 1A and the strength of the device. In some embodiments, the light guide 20, the first freeform surface reflective element 30A, and the second freeform surface reflective element 30B can also be integrally formed (e.g., using a plastic injection molding process), and the first reflective surface 22A and the second reflective surface 22B can be fabricated using a connected plate design, but this disclosure is not limited to this.

[0023] Referring again to Figures 1A and 1C, the light guide 20 may also include a light-shielding element to eliminate stray light SL. For example, the first light-emitting surface 23A and the second light-emitting surface 23B are respectively disposed opposite to the first freeform surface reflecting element 30A and the second freeform surface reflecting element 30B. When the first beam L1 is transmitted to the first light-emitting surface 23A and the second light-emitting surface 23B, part of the beam may be reflected and transmitted back to the light guide 20, forming stray light SL. Alternatively, the random distribution of the beam emitted by the first light source 11 may also easily cause the first beam L1 to generate stray light SL in the light guide 20. The light guide 20 may include a first light-shielding part 24A and a second light-shielding part 24B, which can reduce the proportion of stray light SL transmitted to the first projection surface 40A, thereby improving the uniformity of the intensity of the first beam L1 on the first projection surface 40A. In detail, the first light-shielding part 24A can be disposed on the opposite side of the light-incident surface 21 using a process method such as mechanical assembly, bonding, or co-cavity injection, and connected to the first light-emitting surface 23A and the first reflective surface 22A. Similarly, the second light-shielding part 24B can be disposed on the opposite side of the light-incident surface 21 and connected to the second light-emitting surface 23B and the second reflective surface 22B. The materials of the first light-shielding part 24A and the second light-shielding part 24B can include light-absorbing materials or dispersive materials, but are not limited thereto. In addition, the design of the first light-shielding part 24A and the second light-shielding part 24B can create a accommodating space for the second light source 12. The first light-shielding part 24A and the second light-shielding part 24B can be connected to the light guide 20 using a mechanical connector (not shown), or the first light-shielding part 24A, the second light-shielding part 24B and the light guide 20 can be integrally formed into a single optical element by embedding injection, but this disclosure is not limited thereto.

[0024] Figure 2 shows the relative intensity and angle relationship between the horizontal and vertical light fields of the first beam after it leaves the optical guide in Figure 1A. Referring to both Figure 2 and Figure 1A, the first beam L1, after leaving the optical guide 20, can form the light field shown in Figure 2. In the relationship between the intensity of the light field and the exit angle of the first beam L1, the full width at half maximum (FWHM) of the first dominant wave P1 (or the second dominant wave P2) of the light field can be substantially 20 degrees. Specifically, on the plane formed by directions X and Y, the horizontal light field HF can have a peak value at an angle of 77 degrees (or negative 77 degrees) with direction X, and a corresponding first dominant wave P1 (or second dominant wave P2), with a corresponding FWHM of substantially 20 degrees. On the other hand, in direction D4, the vertical light field VF can have a relatively uniform light intensity distribution. As mentioned above, through the light-receiving surface 21 and the adjustment of the beam by the first reflecting surface 22A and the second reflecting surface 22B, the first beam L1 can be concentrated at the first emitting surface 23A and the second emitting surface 23B. This reduces the generation of stray light SL in the light guide 20, increases the light energy utilization of the first light source 11, and improves the efficiency or brightness of the light source module 1A. In addition, the lower light intensity near the positive viewing angle of the first light source 11 (e.g., +20 degrees to -20 degrees) can also prevent the first beam L1 from being too intense when projected onto the first projection surface 40A, avoiding light mixing with the second beam L2 emitted by the second light source 12, and also helps to improve the optical performance of the second light source 12.

[0025] Referring again to Figure 1B, the light source module 1A may further include a first reflector 50A and a second reflector 50B, respectively disposed on opposite sides of the light guide 20 in direction D4. Furthermore, the first reflector 50A and the second reflector 50B may be configured as white diffusers, for example, using a spraying method. When a portion of the first beam L1 and a portion of the second beam L2 are transmitted toward the thickness direction of the light source module 1A, the first reflector 50A and the second reflector 50B can guide the first beam L1 and the second beam L2 toward the first projection surface 40A, thereby increasing the forward light output of the light source module 1A (e.g., increasing the light intensity ratio in direction X or direction D1) and increasing the light output efficiency of the light source module 1A.

[0026] Figures 3A to 3D are schematic diagrams illustrating the surface design process of the two freeform surface reflective elements of the light source module in Figure 1A. The manufacturing method of the light source module 1A according to this embodiment will be further explained below; please refer to Figures 1A and 3A first. After setting the first light source 11, light guide 20, first freeform surface reflective element 30A, and second freeform surface reflective element 30B, the curvature of the first surface 31A and the second surface 31B can be designed using a program. The uniformity of the intensity of the first beam L1 on the first projection surface 40A can be repeatedly adjusted using loop calculations and the bisection method, ultimately optimizing the design of the first surface 31A and the second surface 31B.

[0027] In detail, by designing the curvature of the first surface 31A and the second surface 31B through programming, after the first beam L1 is reflected by the first surface 31A and the second surface 31B, the angle range R of the incident angle of the first beam L1 on the first projection plane 40A can be obtained, and multiple first intensities (i.e., multiple light intensities when the first beam L1 is incident on the first projection plane 40A) corresponding to the angle range R can be calculated, so as to obtain the average value of the multiple first intensities and multiple first differences between each of the multiple first intensities and the average value. Figure 3A shows the relationship between the multiple first differences (represented as relative differences in Figure 3A) and the corresponding incident angles in the angle range R. For example, the first end value E1 can be an incident angle value in the incident angle range R of the first beam L1, such as an angle of 5 degrees with direction X. The second end value E2 can be another incident angle value in the incident angle range R of the first beam L1, such as an angle of -50 degrees with direction X. By searching the light field distribution within the aforementioned incident angle range R, the incident angle value corresponding to the light intensity distribution within the incident angle range R that is closest to the average value (i.e., the minimum value among multiple first differences) can be found, and this value is defined as the first incident angle A1.

[0028] Next, perform step 1: find the minimum value among multiple first differences and the corresponding first incident angle A1, dividing the incident angle range R into a first range R1 and a second range R2. The first range R1 is from the first endpoint E1 to the first incident angle A1, and the second range R2 is from the second endpoint E2 to the first incident angle A1. For example, in the angle range R of multiple incident angles from 5 degrees to -50 degrees, a loop can be used to search for the minimum value among the multiple first differences within the angle range R, and the incident angle corresponding to the minimum value (i.e., the first incident angle A1, for example, -31 degrees). Therefore, the first range R1 can be defined as 5 degrees to -31 degrees, and the second range R2 can be defined as -31 degrees to -50 degrees.

[0029] Referring to Figure 3B, proceed to step 2: Adjust the curvature of the first surface 31A and the second surface 31B of the first freeform surface reflecting element 30A and the second freeform surface reflecting element 30B to obtain multiple second intensities in the first range R1 and the second range R2 (i.e., multiple light intensities when the first beam L1 is incident on the first projection surface 40A), and calculate the average values ​​of the multiple second intensities in the first range R1 and the second range R2 respectively, as well as multiple second differences between each second intensity and the second average value (represented as relative differences in Figure 3B).

[0030] By comparing Figures 3A and 3B, it can be observed that the relative differences corresponding to each incident angle have decreased, indicating that the uniformity of the first beam L1 on the first projection surface 40A has been improved. When these second differences are lower than or equal to a preset value, it indicates that the uniformity of the first beam L1 on the first projection surface 40A is good, and the curvature of the first surface 31A and the second surface 31B can be fixed.

[0031] If these second differences are higher than a preset value, it means that the uniformity of the first beam L1 on the first projection surface 40A is still poor. Then, a minimum value can be searched in the first range R1 to obtain a second incident angle A2 corresponding to this minimum value, and a minimum value can be searched in the second range R2 to obtain another second incident angle A2 corresponding to this minimum value. For example, the curvature of the freeform surfaces of the first surface 31A and the second surface 31B can be adjusted using a program. Using the bisection method, the minimum value of the multiple second differences corresponding to the first range R1 (5 degrees to -31 degrees) and the incident angle corresponding to the minimum value (i.e., the second incident angle A2, for example, -41 degrees and -14 degrees) can be searched in the loop method of step 1 above in the first range R1 and the second range R2.

[0032] Next, referring to Figures 3C and 3D, the same principle can be applied to repeat the loop in step 1 to search for the minimum value of the relative difference in intensity within multiple ranges (e.g., the third range, the fourth range, the fifth range, the sixth range, etc.) and the corresponding incident angle; and the bisection method in step 2 can be used to repeatedly adjust the intensity distribution within multiple ranges. Finally, as shown in Figure 3D, the uniformity of the intensity of the first beam L1 on the first projection surface 40A can be effectively improved. In some embodiments, during the program adjustment of the first surface 31A and the second surface 31B, a custom energy compensation coefficient can be added according to the actual light energy distribution. Alternatively, the compensated energy distribution curve can be adjusted based on the simulation results.

[0033] Figures 4A and 4B show the distribution of the horizontal and vertical light fields on the projection surface of the light source module of this embodiment. Referring to Figures 4A and 4B, the experimental data simulation shows that by adjusting the curvature of the first surface 31A and the second surface 31B, the uniformity of the intensity of the horizontal light field HF and the vertical light field VF of the first beam L1 can be improved. For example, the uniformity of the first beam L1 of the light source module 1A on the first projection surface 40A can be approximately 83%. In contrast, under the same conditions, the uniformity of the simulation results of emitting the first beam L1 from the first light source 11 alone, with the addition of the first reflector 50A and the second reflector 50B, is approximately 50%. If high-haze or high-dispersion optical elements are used to adjust the uniformity, the overall efficiency of the first light source 11 and the second light source 12 will decrease significantly. Conversely, the light source module 1A can have better light extraction efficiency.

[0034] The following examples illustrate this disclosure in detail, wherein the same components will be labeled with the same symbols, and descriptions of the same technical content will be omitted. For the omitted parts, please refer to the foregoing examples, which will not be repeated below.

[0035] Figure 5 is a side view of a light source module according to an embodiment of this disclosure. Referring to Figure 5, the light source module 1B is similar to the light source module 1A shown in Figure 1A, with the main difference being that the light source module 1B further includes a second projection surface 40B, which is connected to one of the first reflector 50A and the second reflector 50B. Furthermore, the first projection surface 40A has an angle of inclination with direction D4, which is used to reflect the first beam L1 and the second beam L2 through the first projection surface 40A to the second projection surface 40B.

[0036] In detail, the second projection surface 40B may be made of the same or different material as the first projection surface 40A. In some embodiments, the first projection surface 40A, the second projection surface 40B, the first reflector 50A, and the second reflector 50B may all be made of the same material and be integrally molded, but this is not a limitation. By utilizing the reflective effect of the first projection surface 40A and the second projection surface 40B, the light source module 1B allows decorative light sources and projection light sources to have different viewing directions or viewing angles, thereby enhancing the versatility, aesthetics, and taste of the light source module 1B.

[0037] Figure 6 is a side view of a light source module according to an embodiment of this disclosure. Referring to Figure 6, the light source module 1C is similar to the light source module 1B shown in Figure 5, with the main difference being that the second projection surface 40B' of the light source module 1C is a curved surface, suitable for allowing the first beam L1 and the second beam L2 to pass through. Therefore, the light source module 1C can also have similar technical effects to the light source module 1B, which will not be elaborated further here.

[0038] Figure 7 is a partial structural schematic diagram of a light source module according to an embodiment of this disclosure. Referring to Figure 7, the light source module 1D is similar to the light source module 1A shown in Figure 1, with the main difference being that the reflecting surface 22' of the light source module 1D can have a first reflecting surface 22A and a second reflecting surface 22B as in the aforementioned embodiment, and includes metal, diffused particles, or other highly reflective materials. Specifically, the reflecting surface 22' of the light guide 20 of the light source module 1D can reflect the first beam L1 by adding a reflective layer through secondary optical design. The reflecting surface 22' can be manufactured using a surface electroplating process with silver or aluminum metal, or by using white-ejected diffuser material, and the reflecting surface 22' can be processed using ultra-precision machining or a CNC lathe (Computerized Numerical Control Lathe) to achieve mirror polishing, but is not limited to these methods. In this embodiment, the first light source 11 can also be a front-emitting light-emitting diode light source.

[0039] Figures 8A and 8B are schematic diagrams illustrating the arrangement of a light source module according to an embodiment of this disclosure. Referring to Figures 8A and 8B, the optical modules of this embodiment (taking light source module 1A as an example, but not limited thereto) can have various assembly and design methods. For example, multiple light source modules 1A can be arranged in a rectangular array or a circular array to provide decorative light sources or projection light sources required for different designs. Therefore, light source module 1A can be used in different fields (such as panoramic photography or optical sensing), exhibiting excellent versatility.

[0040] In summary, in the light source module of this embodiment, a light guide is used to transmit the first beam of light provided by the first light source (which can be understood as the aforementioned decorative light source) in a third direction to both the first and second directions. Then, two freeform surface reflective elements are used to redirect the first beam, thus creating a space for the placement of the second light source (which can be understood as the aforementioned projection light source) without obstructing the light field of the second beam emitted by the second light source. Therefore, the light source module can achieve compatibility with both light sources. In other words, the light source module of this embodiment can solve the physical limitation of mutual obstruction between the projection light source and the decorative light source when they are located on the same plane.

[0041] Furthermore, compared to the method of using haze elements to homogenize the first beam, this embodiment uses light guides and freeform surface reflection elements to provide the first beam, which can reduce light loss and replace the traditional approach of adjusting haze (sacrificing transmittance) to increase the uniformity of the projection surface brightness, effectively improving the light output efficiency and brightness of the light source module and enhancing the optical effect of the light source module.

[0042] Furthermore, the curved surfaces of the two freeform reflective elements can control the uniformity of the intensity of the first beam on the projection surface, thus effectively homogenizing the light field distribution of the first beam and enhancing product competitiveness.

[0043] 1A, 1B, 1C, 1D: Light source modules 11: First Light Source 12: Second Light Source 20: Optical guide 21: Light-receiving surface 22A: First reflecting surface 22B: Second reflecting surface 22': Reflective surface 23A: First light-emitting surface 23B: Second light-emitting surface 24A: First shading section 24B: Second shading section 30A: First freeform surface reflective element 30B: Second freeform surface reflective element 31A: First surface 31B: Second surface 40A: First projection plane 40B, 40B': Second projection plane 50A: First reflector 50B: Second reflector A1: First angle of incidence A2: Second angle of incidence E1: First terminal value E2: Second terminal value FWHM: Half Height Width HF: Horizontal light field L1: First beam L2: Second beam P1: First Main Wave P2: Second Main Wave R: Angle range R1: First Range R2: Second range SL: Stray light VF: Vertical light field D1, D2, D3, D4, X, Y, Z: Direction

Claims

1. A light source module, comprising: A first light source emits a first light beam; a light guide includes an incident surface, a first reflecting surface, a second reflecting surface, a first emitting surface, and a second emitting surface, wherein the first light beam enters the light guide from the incident surface and is reflected by the first reflecting surface and the second reflecting surface, such that the first light beam is transmitted through the first emitting surface and the second emitting surface in a first direction and a second direction, respectively, wherein the first direction is different from the second direction; two freeform surface reflecting elements are respectively disposed on opposite sides of the light guide corresponding to the first emitting surface and the second emitting surface, the two freeform surface reflecting elements being adapted to reflect the first light beam from the light guide to a first projection surface, and the curved surface of each freeform surface reflecting element is used to adjust the uniformity of the intensity of the first light beam on the first projection surface; And a second light source that emits a second beam of light, the light guide being located between the first light source and the second light source in a third direction, the third direction being different from the first direction and the second direction.

2. The light source module as claimed in claim 1, wherein the first reflecting surface and the second reflecting surface are freeform surfaces adapted to cause total internal reflection of the first light beam.

3. The light source module as claimed in claim 1, wherein the first reflective surface and the second reflective surface are freeform surfaces and include metal or diffused particles.

4. The light source module as claimed in claim 1, wherein the light guide further includes a first light-shielding part and a second light-shielding part, respectively connected to the first light-emitting surface and the second light-emitting surface.

5. The light source module as claimed in claim 1, wherein the first beam forms a light field after leaving the light guide, and in the graph of the relationship between the intensity of the light field and the exit angle of the first beam, the half-width at half maximum (FWHM) of the main wave of the light field is substantially 20 degrees.

6. The light source module as described in claim 1 further includes: Two reflectors are respectively disposed on opposite sides of the light guide in a fourth direction, wherein the first direction, the second direction, and the third direction are located on a plane, and the fourth direction is perpendicular to the plane.

7. The light source module as described in claim 6 further includes: A second projection surface is connected to one of the two reflectors, and the second projection surface has an inclination angle with the fourth direction, so that the first beam and the second beam are reflected from the first projection surface to the second projection surface.

8. The light source module as claimed in claim 7, wherein the second projection surface is a curved surface and is adapted to allow the first beam and the second beam to pass through.

9. The light source module as claimed in claim 1, wherein the first light beam is visible light and the second light beam is white light or infrared light.

10. A method for manufacturing a light source module, comprising: A first light source is provided, which is used to emit a first beam of light; A light guide is provided, comprising an incident surface, a first reflecting surface, a second reflecting surface, a first emitting surface, and a second emitting surface. A first light beam enters the light guide from the incident surface and is reflected by the first and second reflecting surfaces, such that the first light beam is transmitted through the first and second emitting surfaces in a first direction and a second direction, respectively, wherein the first and second directions are different from each other. Two freeform surface reflective elements are provided, respectively disposed on opposite sides of the light guide corresponding to the first and second emitting surfaces, and adapted to reflect the first light beam from the light guide to a projection surface. A second light source is provided to emit a second light beam, and the light guide is located between the first and second light sources in a third direction, which is different from the first and second directions. A range of incident angles when the first beam is incident on the projection surface and a plurality of first intensities corresponding to the incident angle range when the first beam is incident on the projection surface are obtained, so as to generate an average value of the plurality of first intensities, and calculate a plurality of first differences between each of the first intensities and the average value of the plurality of first intensities; Calculate a minimum value among the plurality of first differences and a first incident angle corresponding to the minimum value; divide the incident angle range into a first range and a second range according to the first incident angle; adjust the curvature of the two surfaces of the two freeform surface reflective elements to obtain a plurality of second intensities in the first range and the second range when the first beam is incident on the projection surface, and calculate a plurality of second differences between each of the second intensities and the average values ​​of the plurality of second intensities in the first range and the second range respectively; and when the plurality of second differences are lower than a preset value, determine the curvature of the two surfaces of the two freeform surface reflective elements.

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