Light source module

Abstract

A light source module, comprising: a light emitting unit (120) and a photomask unit (110). The light emitting unit (120) comprises at least one light emitting area, wherein the light emitting area is configured to emit a laser light source; the photomask unit (110) comprises a light inlet (111) and a light outlet (112), wherein a light passing channel is formed between the light inlet (111) and the light outlet (112); the light inlet (111) and the light emitting area are provided on the same surface; the vertical projection of the light inlet (111) on the light emitting area covers the light emitting area; the shape of the light outlet (112) is a corresponding shape of a target light spot; and the thickness of the photomask unit (110) in a direction perpendicular to the light emitting area is an imaging distance of the light emitting unit (120).

Description

Light source module

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on February 28, 2024, with application number 202410220363.X. The entire contents of this application are incorporated by reference into this application. Technical Field

[0002] The embodiments of the present application relate to the field of optical technology, for example, to a light source module. Background Art

[0003] Vertical-Cavity Surface-Emitting Laser (VCSEL) has increasingly broad application prospects in the fields of optical communications, optical processing and optical display.

[0004] VCSEL applications usually require a surface light source of a specific shape. In order to produce a specific light spot, a light homogenizer, lens or other diffraction schemes are usually used for optical imaging. Among them, light homogenizers and diffraction schemes mostly form a certain microstructure on the glass through nano-imprinting resin to achieve a specific light spot. These microstructured resins are difficult to use in energy transmission situations, and the energy loss is large, resulting in low transmission efficiency.

[0005] The lens solution has high requirements for focal length. If the laser is used at close range, such as within 10mm, a longer focal length is unacceptable. Furthermore, the large light-emitting area of ​​VCSELs used for energy transmission requires a larger lens aperture, which also increases the size and cost of the entire heating system.

[0006] Summary of the Invention

[0007] The present application provides a light source module that reduces light energy transmission loss and system size, thereby reducing production costs.

[0008] The present application provides a light source module, comprising: a light-emitting unit and a light shield unit; the light-emitting unit comprises at least one light-emitting area, and the light-emitting area is configured to emit a laser light source; the light shield unit comprises a light inlet and a light outlet, and a light passage is formed between the light inlet and the light outlet; the light inlet and the light-emitting area are arranged on the same surface, wherein the vertical projection of the light inlet on the light-emitting area covers the light-emitting area; the shape of the light outlet corresponds to the shape of the target light spot; the thickness of the light shield unit in the direction perpendicular to the light-emitting area is the imaging distance of the light-emitting unit.

[0009] Optionally, a reflective film is provided on the side wall of the light passage.

[0010] Optionally, the reflective film includes at least one of silver, aluminum, silicon oxide, titanium oxide, aluminum oxide and magnesium fluoride.

[0011] Optionally, a vertical projection of the light outlet on the light emitting area covers a vertical projection of the light inlet on the light emitting area.

[0012] Optionally, the light divergence angle of the light emitting area is greater than or equal to the angle formed by the side wall of the light passage and the light inlet.

[0013] Optionally, the light source module further includes a heat sink; a conductive circuit is provided on the heat sink, the light-emitting unit is provided on the heat sink, the light-emitting unit is electrically connected to the conductive circuit, and the conductive circuit is provided to lead out the connection end of the light-emitting unit.

[0014] Optionally, the mask unit is bonded to the heat dissipation plate through an adhesive layer.

[0015] Optionally, the heat sink is made of copper, copper diamond, aluminum, stainless steel, silicon carbide, aluminum nitride, aluminum oxide or alloy metal.

[0016] Optionally, the light-emitting unit is a vertical cavity surface emitting laser.

[0017] Optionally, the mask unit is made of glass, sapphire or metal. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 is a schematic structural diagram of a light source module provided in an embodiment of the present application;

[0019] FIG2 is a structural diagram of another light source module provided in an embodiment of the present application;

[0020] FIG3 is a structural diagram of another light source module provided in an embodiment of the present application;

[0021] FIG4 is a schematic diagram of the angle at which a light source is emitted according to an embodiment of the present application;

[0022] FIG5 is a schematic diagram of energy distribution of a light spot in FIG1 ;

[0023] FIG6 is a schematic diagram of energy distribution of a light spot in FIG2 ;

[0024] FIG7 is a structural diagram of another light source module provided in an embodiment of the present application;

[0025] FIG8 is a flow chart of a preparation process of a light source module provided in an embodiment of the present application. DETAILED DESCRIPTION

[0026] The following will describe the technical solutions in the embodiments of this application in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0027] In applications, VCSELs usually need to realize a surface light source of a specific shape. In order to produce a specific light spot, a light homogenizer, lens, or other diffraction scheme is usually used for optical imaging. Among them, light homogenizers and diffraction schemes mostly form a certain microstructure on the glass through nano-imprinting resin to achieve a specific light spot. These microstructured resins are difficult to use in energy transmission situations, and the energy loss is large, resulting in low transmission efficiency.

[0028] In addition, in some heating applications, such as heating specific materials such as liquid oil, filaments, granules, sheets, powders and other solid materials, energy will cause the temperature to rise, and the resin structure will quickly degenerate at high temperatures, making it unusable in industrial or consumer heating fields.

[0029] The lens solution has high requirements for focal length. If the laser is used at close range, such as within 10mm, a longer focal length is unacceptable. Furthermore, the large light-emitting area of ​​VCSELs used for energy transmission requires a larger lens aperture, which also increases the size and cost of the entire heating system.

[0030] FIG1 is a structural diagram of a light source module provided in an embodiment of the present application, which includes: a light emitting unit 120 and a light shield unit 110;

[0031] The light emitting unit 120 includes at least one light emitting area, which is configured as an emitting laser light source;

[0032] The light mask unit 110 includes a light inlet 111 and a light outlet 112, and a light passage 130 is formed between the light inlet 111 and the light outlet 112; the light inlet 111 and the light emitting area are arranged on the same surface, wherein the vertical projection of the light inlet 111 on the light emitting area covers the light emitting area; the shape of the light outlet 112 corresponds to the shape of the target light spot; the thickness of the light mask unit 110 in the direction perpendicular to the light emitting area is the imaging distance of the light emitting unit 120.

[0033] The light-emitting unit 120 is configured as an output laser light source. Exemplarily, the light-emitting unit 120 can utilize a VCSEL light source. VCSEL light sources offer advantages in integration, detection, and optical output coupling due to their light emission direction perpendicular to the wafer and high beam quality. The light-emitting unit 120 has at least one light-emitting region, corresponding to the region where the laser light source is emitted from the light-emitting unit 120. A single light-emitting unit 120 can have multiple light-emitting regions, or multiple light-emitting units 120 can form a light-emitting array to form corresponding light-emitting regions.

[0034] The light shield unit 110 is arranged on the light-emitting side of the light-emitting unit 120, and the light inlet 111 and the light-emitting area are arranged on the same surface. There is a light passage 130 between the light inlet 111 and the light outlet 112. The light source emitted by the light-emitting unit 120 can enter through the light inlet 111, be transmitted by the light passage 130, and finally be output from the light outlet 112. In order to ensure the energy transmission of the light-emitting area, the light-emitting area is arranged in the area surrounded by the light inlet 111, that is, the vertical projection of the light inlet 111 on the light-emitting area covers the light-emitting area, so that the light source energy output by the light-emitting unit 120 can all enter the light passage 130. The light outlet 112 of the light shield unit 110 can be designed according to the corresponding shape of the preset target light spot, so as to achieve different light spot shape output at the light outlet 112. Figure 2 is a structural schematic diagram of another light source module provided in an embodiment of the present application, and Figure 3 is a structural schematic diagram of another light source module provided in an embodiment of the present application. Referring to Figures 1 to 3, the light outlet 112 is designed to be rectangular, pentagonal, and pentagonal, respectively. In other embodiments, the light outlet 112 can be configured to have other regular or irregular shapes to achieve a special-shaped light spot output. It should be noted that the shape of the light inlet 111 can be a regular shape such as a rectangle, a pentagon, or a pentagon, or can be the same shape as the light outlet 112 but scaled down, without limitation.

[0035] The thickness of the mask unit 110 in the direction perpendicular to the light-emitting area adopts the imaging distance of the light-emitting unit 120, and the imaging distance is the processing distance. For example, in a close-range usage scenario, such as within 10 mm, the thickness of the mask unit 110 is the usage distance of the light-emitting unit 120, and the processing material is placed at the light outlet 112. The target light spot output by the light outlet 112 can be directly used for processing, and there is no need for intermediate imaging structures such as light homogenizers or lenses, thereby avoiding the problems of large energy loss and large system size.

[0036] The technical solution provided by the embodiment of the present application is to set a light shield unit on the light-emitting side of the light-emitting unit and set the light-emitting area within the area of ​​the light inlet. The output light source of the light-emitting unit can enter through the light inlet, be transmitted by the light-passing channel, and finally be output from the light outlet. The output of irregular light spots can be achieved by utilizing different shape designs of the light outlet. The thickness of the light shield unit is set to the imaging distance of the light-emitting unit. Therefore, the target light spot output from the light outlet can be directly used for subsequent processing, thereby eliminating the need to set intermediate imaging structures such as light homogenizers or lenses, thereby avoiding the problems of large energy loss and large system size caused by the intermediate imaging structure, and reducing certain production costs.

[0037] In some embodiments, to further improve the output efficiency of the light source emitted by the light-emitting unit 120 within the light passage 130, a reflective film can be provided on the sidewalls of the light passage 130. By providing the reflective film on the sidewalls of the light passage 130, the emissivity within the light passage 130 can be increased to over 99.9%. In this way, the light emitted by the entire light-emitting unit 120 can be uniformly reflected within the mask unit 110, and as much light source energy as possible can be output to the light outlet 112. Exemplarily, the reflective film can be a dielectric film formed through optical design using silver, aluminum, silicon oxide, titanium oxide, aluminum oxide, and magnesium fluoride. The reflective film can be a single-layer film or a multi-layer film, such as a multi-layer periodic dielectric film composed of silicon oxide / aluminum oxide.

[0038] In some embodiments, the size of the light outlet 112 is larger than the size of the light inlet 111, the vertical projection of the light outlet 112 on the light-emitting area covers the vertical projection of the light inlet 111 on the light-emitting area, the size of the light inlet 111 is close to the size of the light-emitting area, and the size of the light inlet 111 is consistent with the shape of the target light spot. That is, the light inlet 111 and the light outlet 112 form a structure similar to a "funnel", so that more light can be reflected by the side wall of the light channel 130 and then output by the light outlet 112.

[0039] In some embodiments, Figure 4 is a schematic diagram of the angle of emission of a light source provided in an embodiment of the present application. Referring to Figure 4 , the light divergence angle A of the light emitting area is greater than or equal to the angle B formed by the side wall of the light channel 130 and the light inlet 111.

[0040] The light emitted by the light-emitting unit 120 has a certain divergence angle A during the outward emission process. When the divergence angle A is greater than or equal to the angle B formed by the side wall of the light passage 130 and the light inlet 111, the emitted light is reflected by the reflective film on the side wall of the light passage 130 during the transmission process, so that all the light energy is reflected back to the main light path and output from the light outlet 112.

[0041] For example, based on the above embodiment, the light-emitting area is set at the center of the light inlet 111, and the centers of the light inlet 111 and the light outlet 112 are on the same straight line. The light emitted from the light-emitting area is reflected by the side wall of the light passage 130 and output from the light outlet 112. Figure 5 is a schematic diagram of the energy distribution of a light spot in Figure 1, and Figure 6 is a schematic diagram of the energy distribution of a light spot in Figure 2. Referring to Figures 5 and 6, the surface energy of the light outlet 112 is evenly distributed, and an energy distribution in the shape of a target light spot can be formed.

[0042] In some embodiments, FIG7 is a structural diagram of another light source module provided in an embodiment of the present application. Referring to FIG7 , the light source module further includes a heat dissipation plate 140 ;

[0043] A conductive circuit 141 is provided on the heat dissipation plate 140 . The light emitting unit 120 is provided on the heat dissipation plate 140 . The light emitting unit 120 is electrically connected to the conductive circuit 141 . The conductive circuit 141 is provided as a connection end leading out of the light emitting unit 120 .

[0044] The heat sink 140 is a highly thermally conductive material. Exemplarily, the heat sink 140 can be made of copper, copper diamond, aluminum, stainless steel, silicon carbide, aluminum nitride, aluminum oxide, or an alloy metal. The light-emitting unit 120 is disposed on the heat sink 140 and can be soldered to the heat sink 140 using a highly thermally conductive adhesive such as silver paste or silver glue, or other solders, such as gold germanium, gold tin, or indium. The heat sink 140 dissipates heat from the light-emitting unit 120. A conductive circuit 141 is disposed on the heat sink 140. The light-emitting unit 120 can be connected to the conductive circuit 141 via a gold wire. The conductive circuit 141 is used to lead out the connection end of the light-emitting unit 120. The connection end can include the positive and negative electrodes of the light-emitting unit 120, enabling rearrangement of the positive and negative electrodes or connection to an external circuit. The mask unit 110 and the heat sink 140 can be connected by an adhesive layer, wherein the adhesive layer can be made of a material such as glue or solder. In order to ensure the mechanical strength of the mask unit 110 and the stability during thermal processing, the mask unit 110 may be made of glass, sapphire or metal.

[0045] In some embodiments, FIG8 is a flowchart of a preparation process of a light source module according to an embodiment of the present application, and FIG8 includes:

[0046] S10, setting a heat sink 140, and setting a conductive circuit 141 on the surface of the heat sink 140. The heat sink 140 can be made of a high thermal conductivity material or alloy such as copper, copper diamond, aluminum, stainless steel, silicon carbide, aluminum nitride or aluminum oxide;

[0047] S20: The light-emitting unit 120 uses a VCSEL chip. At least one VCSEL chip is placed on the heat sink 140. The VCSEL chip can be soldered to the heat sink 140 using a high-thermal-conductivity glue such as silver paste or silver glue, or other solders such as gold germanium, gold tin, or indium. Then, the positive or negative electrode of the VCSEL is connected to the conductive circuit 141 on the heat sink 140 using a gold wire.

[0048] S30. A mask unit 110 is provided on the light-emitting side of the VCSEL chip. The light inlet 111 of the mask unit 110 is provided on the same surface as the light-emitting area of ​​the VCSEL chip, and the light-emitting area is provided within the light inlet 111. The shape of the light outlet 112 of the mask unit 110 corresponds to the shape of the target light spot, such as a regular shape such as a rectangle, pentagon, or pentagon. An irregular shape can also be provided to achieve a special-shaped light spot output. The thickness of the mask unit 110 in a direction perpendicular to the light-emitting area is equal to the imaging distance of the light-emitting unit 120.

[0049] Exemplarily, the sidewalls of the light passage 130 of the mask unit 110 may also be coated with a reflective film. The reflective film may be an optically designed dielectric film such as silver, aluminum, silicon oxide, titanium oxide, aluminum oxide, or magnesium fluoride, so that the reflectivity of the light emitted by the VCSEL chip exceeds 99.9%, thereby meeting practical purposes. The divergence angle A of the VCSEL chip is greater than or equal to the angle B formed by the sidewalls of the light passage 130 of the mask unit 110 and the light inlet 111. Therefore, during the transmission process, the light emitted by the VCSEL chip can be reflected by the reflective film on the sidewalls of the light passage 130, so that all the light energy is reflected back to the main light path and output from the light outlet 112. The mask unit 110 and the heat sink 140 can be connected by materials such as glue and solder.

Claims

1. A light source module, comprising: Light emitting unit and light shield unit; The light-emitting unit includes at least one light-emitting area, and the light-emitting area is configured to emit a laser light source; The light shield unit includes a light inlet and a light outlet, and a light passage is formed between the light inlet and the light outlet; the light inlet and the light emitting area are arranged on the same surface, wherein the vertical projection of the light inlet on the light emitting area covers the light emitting area; the shape of the light outlet is the corresponding shape of the target light spot; the thickness of the light shield unit in the direction perpendicular to the light emitting area is the imaging distance of the light emitting unit.

2. The light source module according to claim 1, wherein: The side wall of the light passage is provided with a reflective film.

3. The light source module according to claim 2, wherein: The reflective film includes at least one of silver, aluminum, silicon oxide, titanium oxide, aluminum oxide and magnesium fluoride.

4. The light source module according to any one of claims 1 to 3, wherein: The vertical projection of the light outlet on the light emitting area covers the vertical projection of the light inlet on the light emitting area.

5. The light source module according to claim 4, wherein: The light divergence angle of the light emitting area is greater than or equal to the angle formed by the side wall of the light passage and the light inlet.

6. The light source module according to claim 1, further comprising a heat dissipation plate; A conductive circuit is provided on the heat dissipation plate, the light emitting unit is provided on the heat dissipation plate, the light emitting unit is electrically connected to the conductive circuit, and the conductive circuit is provided to lead out a connection end of the light emitting unit.

7. The light source module according to claim 6, wherein: The photomask unit is bonded to the heat dissipation plate via an adhesive layer.

8. The light source module according to claim 6, wherein: The heat dissipation plate is made of copper, copper diamond, aluminum, stainless steel, silicon carbide, aluminum nitride, aluminum oxide or alloy metal.

9. The light source module according to claim 1, wherein: The light emitting unit is a vertical cavity surface emitting laser.

10. The light source module according to claim 1, wherein: The material of the mask unit is glass, sapphire or metal.

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