Light source device and optical imaging system

Abstract

The invention discloses a light source device and an optical imaging system. The first laser light source comprises a first laser module and a second laser module, the first laser module is used for generating first laser, and the second laser module is used for generating second laser. The second laser light source comprises a third laser module and a fourth laser module, the third laser module is used for generating third laser, and the fourth laser module is used for generating fourth laser. The first polarization light combination module is arranged on a light path where the first laser and the third laser are located and used for generating first mixed light. The second polarization light combination module is arranged on the light path where the second laser and the fourth laser are located and used for generating second mixed light. The wavelength light combination module is arranged on a light path where the first mixed light and the second mixed light are located. According to the light source device in the embodiment, light combination is conducted on multiple paths of laser in the mode that polarization light combination is conducted firstly and then wavelength light combination is conducted, light spots of finally generated emergent light can be small, and the design difficulty and hardware cost of elements in a follow-up light path are reduced.

Description

Technical Field

[0001] This application relates to the field of optical imaging technology, and more specifically, to a light source device and an optical imaging system. Background Technology

[0002] Currently, the main light source used in projection equipment is the RGB laser light source, which has advantages such as high brightness, wide color gamut, and good monochromaticity. However, as the size of laser display projections increases, higher requirements are placed on the output energy of the laser.

[0003] To achieve higher energy output from laser sources, researchers typically increase the number of laser arrays within the laser source. However, if the optical combining path design of the laser source is flawed, it can lead to an increase in the size of the final emitted laser spot. This necessitates a corresponding increase in the aperture and thickness of components in the subsequent optical path (e.g., lenses, compound eyes), thereby raising the hardware cost and design complexity of the subsequent optical path. Summary of the Invention

[0004] This application provides a light source device and an optical imaging system.

[0005] According to a first aspect of this application, embodiments of this application provide a light source device, which includes a first laser source, a second laser source, a first polarization combining module, a second polarization combining module, and a wavelength combining module. The first laser source includes a first laser module and a second laser module. The first laser module generates a first laser beam with a first polarization state. The second laser module generates a second laser beam with a second polarization state. The first and second polarization states are different, and the first and second lasers are of opposite colors. The second laser source includes a third laser module and a fourth laser module. The third laser module generates a third laser beam with a first polarization state. The fourth laser module generates a fourth laser beam with a second polarization state; the third and fourth lasers are of opposite colors. The first polarization combining module is disposed in the optical paths of the first and third lasers, and is used to perform polarization combining with the other laser beam after converting the polarization state of one of the laser beams to generate a first mixed light. The second polarization combining module is positioned in the optical path containing the second and fourth lasers. It is used to combine the polarization of one of the lasers with the other laser after converting its polarization state, thereby generating a second mixed light. The wavelength combining module is positioned in the optical path containing the first and second mixed light, and is used to combine the wavelengths of the first and second mixed light to generate the outgoing light.

[0006] According to a second aspect of this application, embodiments of this application also provide an optical imaging system, which includes the aforementioned light source device and light modulator. The light source device is used to generate outgoing light, and the light modulator is disposed in the optical path of the outgoing light.

[0007] This application provides a light source device and an optical imaging system. The light source device includes a first laser source, a second laser source, a first polarization combining module, a second polarization combining module, and a wavelength combining module. The first and second laser sources each have two laser modules. The lasers generated by the first laser module in the first laser source and the third laser module in the second laser source have the same polarization state, which is a first polarization state (e.g., P-polarization state). The lasers generated by the second laser module in the first laser source and the fourth laser module in the second laser source have the same polarization state, which is a second polarization state (e.g., S-polarization state).

[0008] The first polarization combining module is used to polarize and combine the first laser generated by the first laser module and the third laser generated by the third laser module. Since the two lasers have the same polarization state, the first polarization combining module first changes the polarization state of one laser before combining it with the other. For example, it converts the P-polarized first laser to an S-polarized state and then combines it with the P-polarized third laser to produce a first mixed light. Because the P-polarized third laser and the S-polarized first laser can spatially compensate for each other, the resulting first mixed light spot is relatively small.

[0009] The second polarization combining module is used to polarize and combine the second laser generated by the second laser module and the fourth laser generated by the fourth laser module. Since the two lasers have the same polarization state, the second polarization combining module first changes the polarization state of one laser before combining it with the other. For example, it converts the S-polarized fourth laser to a P-polarized state and then combines it with the S-polarized second laser to produce a second mixed light. Because the S-polarized second laser and the P-polarized fourth laser can spatially compensate for each other, the resulting second mixed light spot is smaller.

[0010] Finally, the wavelength combining module performs wavelength combining on the first and second mixed beams after polarization combining to generate the output light. Therefore, the light source device in this embodiment uses polarization combining followed by wavelength combining to combine multiple laser beams, which results in a smaller spot size of the final output light, reducing the design difficulty and hardware cost of components in the subsequent optical path.

[0011] Furthermore, since the multiple lasers in this embodiment have two different polarization states, the coherence of the laser can be weakened, thereby reducing the contrast of the speckle in the laser, which is beneficial to improving the imaging quality of the optical imaging system equipped with the light source device. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a schematic diagram of the structure of the light source device provided in the embodiments of this application.

[0014] Figure 2 yes Figure 1 A schematic diagram showing the placement of the first and second laser sources.

[0015] Figure 3 yes Figure 1 A schematic diagram of the structure of the first laser source in China.

[0016] Figure 4 yes Figure 1 Another structural schematic diagram of the first laser source in China.

[0017] Figure 5 yes Figure 1 Another structural schematic diagram of the first laser source in China.

[0018] Figure 6 yes Figure 1 Another schematic diagram showing the placement of the first and second laser sources.

[0019] Figure 7 yes Figure 1 Another schematic diagram showing the placement of the first and second laser light sources.

[0020] Figure 8 yes Figure 1 Another schematic diagram showing the arrangement of the first and second laser sources.

[0021] Figure 9 yes Figure 1 A cross-sectional schematic diagram of the first polarization combining unit.

[0022] Figure 10 yes Figure 1 A cross-sectional schematic diagram of the second polarization combining unit.

[0023] Figure 11 This is another structural schematic diagram of the light source device provided in the embodiments of this application.

[0024] Figure 12 This is another structural schematic diagram of the light source device provided in the embodiments of this application.

[0025] Figure 13 This is a schematic diagram of the structure of the optical imaging system provided in the embodiments of this application. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative effort are within the scope of protection of the present application.

[0027] This application provides a light source device 100, which is a hybrid light source that combines multiple laser beams. This light source device 100 has advantages such as high brightness, simple optical path, and low hardware cost, and can be widely used in projection devices (e.g., micro projectors, short-throw projectors, vehicle-mounted projectors), laser TVs, engineering projectors, and laser video walls. Preferably, the light source device 100 can be a one-piece package structure, which may be provided with a light outlet (not shown in the figure) for emitting emitted light. Because the light source device 100 is a one-piece package structure, it can be matched with various product scenarios, offering high flexibility and helping to reduce product development cycles. Furthermore, modularizing the light source device 100 also helps to reduce the installation difficulty of the light source device 100.

[0028] Please see Figure 1 and Figure 2 In this embodiment, the light source device 100 may include a first laser light source 10, a second laser light source 20, a first polarization combining module 30, a second polarization combining module 40, and a wavelength combining module 50. The first laser light source 10 may include a first laser module 120 and a second laser module 140. The first laser module 120 generates a first laser L1, and the polarization state of the first laser L1 is a first polarization state. The second laser module 140 generates a second laser L2, and the polarization state of the second laser L2 is a second polarization state. The first polarization state and the second polarization state are not the same. In this embodiment, both the first polarization state and the second polarization state are linearly polarized states, and they are linearly orthogonal. For example, the first polarization state may be a P-polarized state, and the second polarization state may be an S-polarized state. Alternatively, the first polarization state may be an S-polarized state, and the second polarization state may be a P-polarized state. Furthermore, the first laser L1 and the second laser L2 are of different colors. For example, the first laser L1 can be green light, blue light, or a mixture of blue and green light, and the second laser L2 can be red light or other colors. This embodiment does not specifically limit the colors and polarization states of the first laser L1 and the second laser L2.

[0029] The second laser source 20 may include a third laser module 210 and a fourth laser module 230. The third laser module 210 generates a third laser L3, which has a first polarization state. The fourth laser module 230 generates a fourth laser L4, which has a second polarization state. The third laser L3 and the fourth laser L4 are of different colors. Therefore, in this embodiment, the first laser L1 and the third laser L3 have the same polarization state, and the second laser L2 and the fourth laser L4 have the same polarization state.

[0030] It should be noted that the first laser L1 and the third laser L3 are the same color, and the third laser L3 and the first laser L1 can be located in the same wavelength band. For example, the third laser L3 and the first laser L1 can both be a mixture of blue and green light, and both are located in the wavelength band where blue or green light is located (e.g., 440nm to 580nm). The second laser L2 and the fourth laser L4 are the same color, and the fourth laser L4 and the second laser L2 can be located in the same wavelength band. For example, the fourth laser L4 and the second laser L2 can both be red light, and both are located in the wavelength band where red light is located (e.g., 625nm to 740nm).

[0031] The first polarization combining module 30 is disposed in the optical path containing the first laser L1 and the third laser L3. It is used to combine the polarization of one of the lasers, L1 and L3, with the other laser to generate a first mixed light H1. Since the two lasers have the same polarization state, the first polarization combining module 30 first changes the polarization state of one laser before combining it with the other. For example, it converts the P-polarized first laser L1 to an S-polarized state and then combines it with the P-polarized third laser L3 to generate the first mixed light H1. Because the P-polarized third laser L3 and the S-polarized first laser L1 can spatially compensate for each other, the resulting spot size of the first mixed light H1 is relatively small.

[0032] The second polarization combining module 40 is disposed in the optical path containing the second laser L2 and the fourth laser L4. It is used to combine the polarization of one of the lasers, L2 and L4, with the other laser to generate a second mixed light H2. Since the two lasers have the same polarization state, the second polarization combining module 40 first changes the polarization state of one laser before combining it with the other. For example, it converts the S-polarized fourth laser L4 to a P-polarized state and then combines it with the S-polarized second laser L2 to generate the second mixed light H2. Because the S-polarized second laser L2 and the P-polarized fourth laser L4 can spatially compensate for each other, the resulting second mixed light H2 has a smaller spot size.

[0033] A wavelength combining module 50 is disposed in the optical path containing the first mixed light H1 and the second mixed light H2. It is used to perform wavelength combining on the first mixed light H1 and the second mixed light H2 to generate the outgoing light O. Therefore, the light source device 100 in this embodiment uses a method of first polarization combining and then wavelength combining to combine multiple lasers, which can result in a smaller spot size of the final outgoing light O, reducing the design difficulty and hardware cost of components in the subsequent optical path.

[0034] Furthermore, since the multiple lasers in this embodiment have two different polarization states, the coherence of the laser can be weakened, thereby reducing the contrast of speckle in the laser, which is beneficial to improving the imaging quality of the optical imaging system equipped with the light source device 100.

[0035] The following is a description of the various components in the light source device 100.

[0036] In this embodiment, the first laser source 10 may include a first laser module 120 and a second laser module 140. Specifically, the first laser module 120 and the second laser module 140 may be packaged in the same laser to form the first laser source 10.

[0037] The first laser module 120 is used to generate a first laser L1. In this embodiment, the first laser L1 is a beam of light composed of a mixture of blue and green light. Please refer to [link / reference]. Figure 3 The first laser module 120 may include a first laser unit 1210 and a second laser unit 1230. The first laser unit 1210 generates a first sub-laser L11, and the second laser unit 1230 generates a second sub-laser L12. The wavelengths of the second laser L12, the first sub-laser L11, and the second sub-laser L12 are different from each other. For example, the first sub-laser L11 may be green light, the second sub-laser L12 may be blue light, and the second laser L2 may be red light. In some other possible embodiments, the first laser L1 may be a single color of light, or light composed of a mixture of multiple other colors of light; this embodiment does not specifically limit this. Furthermore, since the polarization state of the first laser L1 is a first polarization state, the polarization states of the first sub-laser L11 and the second sub-laser L12 are the same, both being first polarization states. Exemplarily, the first sub-laser L11 and the second sub-laser L12 may both be P-polarized or both S-polarized. In the following description, the first polarization state being P-polarized is used as an example.

[0038] Specifically, the first laser unit 1210 may include a plurality of first laser subunits 1212, which are arranged at intervals along a first designated direction W to jointly form a first sub-laser L11. The number of first laser subunits 1212 may be 2, 3, 6, 8, etc. The second laser unit 1230 may include a plurality of second laser subunits 1232, which are arranged at intervals along the first designated direction W to jointly form a second sub-laser L12. The number of second laser subunits 1232 may be 2, 3, 4, 5, etc.

[0039] In some possible embodiments, please refer to Figure 3 and Figure 4 The first laser unit 1210 and the second laser unit 1230 can be arranged at intervals in a first specified direction W, such that the plurality of first laser subunits 1212 included in the first laser unit 1210 and the plurality of second laser subunits 1232 included in the second laser unit 1230 are located in the same column and are spaced apart.

[0040] In some other possible embodiments, please refer to Figure 5 The first laser unit 1210 and the second laser unit 1230 can be arranged at intervals in the second specified direction H, such that the plurality of first laser subunits 1212 included in the first laser unit 1210 and the plurality of second laser subunits 1232 included in the second laser unit 1230 are respectively located in two columns and spaced apart from each other. The second specified direction H is perpendicular to the first specified direction W.

[0041] The second laser module 140 is used to generate a second laser L2. In this embodiment, the second laser L2 is red light, and the polarization state of the second laser L2 is S-polarization, that is, the second polarization state is S-polarization. In some other possible embodiments, the second laser L2 may also be light of other single colors, or light composed of a mixture of multiple colors of light; this embodiment does not specifically limit this.

[0042] Specifically, the second laser module 140 and the first laser module 120 are arranged at intervals in a second designated direction H. The second laser module 140 may include multiple third laser sub-units 1400, which are arranged at intervals in a first designated direction W to jointly form the second laser L2. The number of third laser sub-units 1400 can be 4, 6, 8, etc. Figure 3 and Figure 4In the illustrated embodiment, multiple third laser subunits 1400 are arranged in a single column, spaced apart from a single column formed by multiple first laser subunits 1212 and multiple second laser subunits 1232 in a second designated direction H. Therefore, the first laser source 10 in this embodiment is an RGB three-color laser source, and the RGB three-color laser adopts an asymmetrical packaging method. Figure 5 In the illustrated embodiment, the plurality of third laser subunits 1400 are arranged in two columns, which are spaced apart from the two columns of the plurality of first laser subunits 1212 and the plurality of second laser subunits 1232 in the second designated direction H. That is, the second laser module 140, the second laser unit 1230, and the first laser unit 1210 are arranged alternately in the second designated direction H. This embodiment does not specifically limit the number of each laser subunit or the specific arrangement.

[0043] In this embodiment, the second laser source 20 may include a third laser module 210 and a fourth laser module 230. Specifically, the third laser module 210 and the fourth laser module 230 may be packaged in the same laser to form the second laser source 20.

[0044] In some possible embodiments, the number and arrangement of each laser subunit in the second laser source 20 and the first laser source 10 can be the same. That is, the second laser source 20 and the first laser source 10 are two laser generators with identical structures, thereby saving hardware costs for the light source device 100. Therefore, the features of the second laser source 20 can refer to and follow the features of the first laser source 10, and will not be described in detail here for the sake of brevity.

[0045] Specifically, the third laser module 210 may include a third laser unit 2100 and a fourth laser unit 2120. The third laser unit 2100 is used to generate a third sub-laser L31, and the fourth laser unit 2120 is used to generate a fourth sub-laser L32. The third sub-laser L31 and the first sub-laser L11 are the same color, the fourth sub-laser L32 and the second sub-laser L12 are the same color, and the fourth laser L4 and the second laser L2 are the same color. The features of the third laser unit 2100 can refer to and adopt the features of the first laser unit 1210, and the features of the fourth laser unit 2120 can refer to and adopt the features of the second laser unit 1230. For the sake of brevity, these will not be elaborated further here.

[0046] In some other possible embodiments, the number or arrangement of the laser sub-units in the second laser source 20 and the first laser source 10 may be different. For example, in... Figure 3In the illustrated embodiment, the first laser module 120 in the first laser source 10 is located on the left, the second laser module 140 is located on the right, and the first laser unit 1210 is located above the second laser unit 1230. In the second laser source 20, the third laser module 210 is located on the left, the fourth laser module 230 is located on the right, and the fourth laser unit 2120 can be located above the third laser unit 2100. Therefore, the arrangement of the laser sub-units in the first laser source 10 and the second laser source 20 is different. Specifically, the number and arrangement of each laser sub-unit in the second laser source 20 and the first laser source 10 can be determined based on the specific implementation and placement of the first polarization combining module 30, the second polarization combining module 40, and the wavelength combining module 50; this embodiment does not impose specific limitations on this.

[0047] In this embodiment, the second laser source 20 and the first laser source 10 are placed perpendicular to each other. Specifically, please refer again to... Figure 2 The emission directions of the first laser L1 and the second laser L2 are perpendicular to the first plane P1, respectively. The emission directions of the third laser L3 and the fourth laser L4 are perpendicular to the second plane P2, respectively. The first plane P1 and the second plane P2 are mutually perpendicular. It should be noted that "the first plane P1 and the second plane P2" are only geometric features used to describe the relative positional relationship between the second laser source 20 and the first laser source 10. In the actual structure of the second laser source 20 and the first laser source 10, the first plane P1 and the second plane P2 may not actually exist.

[0048] In this embodiment, the light source device 100, by vertically placing the second laser light source 20 and the first laser light source 10, achieves a more compact overall optical path structure. Furthermore, vertical placement also enables symmetrical optical distribution when multiple laser beams are combined. The specific arrangement of the second laser light source 20 and the first laser light source 10 will be described below.

[0049] In some possible embodiments, the first laser L1 and the third laser L3 jointly define the first laser reference plane. The second laser L2 and the fourth laser L4 jointly define the second laser reference plane, and the first and second laser reference planes are parallel. It should be noted that the first laser L1 and the third laser L3 in "the first laser L1 and the third laser L3 jointly define the first laser reference plane" refer to light rays that have not propagated to the first polarization combining module 30. The second laser L2 and the fourth laser L4 in "the second laser L2 and the fourth laser L4 jointly define the second laser reference plane" refer to light rays that have not propagated to the second polarization combining module 40. Because the first and second laser reference planes are parallel, the first laser L1 and the third laser L3 can combine light on the same side, and the second laser L2 and the fourth laser L4 can combine light on the other side, allowing the two sets of light rays to be combined independently.

[0050] Specifically, the first laser module 120 and the second laser module 140 are spaced apart on the first direction A1, and the third laser module 210 and the fourth laser module 230 are spaced apart on the first direction A1. The first direction A1 is parallel to the first plane P1 and the second plane P2, respectively. It is easy to understand that the first direction A1 is in the same direction as the aforementioned second designated direction H.

[0051] exist Figure 2 In the embodiment shown, the first laser source 10 can be adopted Figure 3 or Figure 4 The structure is as follows. Specifically, the first laser unit 1210 and the second laser unit 1230 are spaced apart on the second direction A2, and the third laser unit 2100 and the fourth laser unit 2120 are spaced apart on the third direction A3. The second direction A2 is parallel to and perpendicular to the first plane P1. The third direction A3 is parallel to and perpendicular to the second plane P2, that is, the first direction A1, the second direction A2, and the third direction A3 are all perpendicular to each other. It is easy to understand that the second direction A2 is in the same direction as the first designated direction W corresponding to the first laser source 10, and the third direction A3 is in the same direction as the first designated direction W corresponding to the second laser source 20.

[0052] Specifically, in Figure 2 In the illustrated embodiment, the first laser unit 1210 is located on the side of the second laser unit 1230 away from the second laser source 20, and the fourth laser unit 2120 is located on the side of the third laser unit 2100 away from the first laser source 10. Therefore, Figure 2 The laser sub-units in the first laser source 10 and the second laser source 20 are arranged in the same way.

[0053] In some other possible embodiments, the first laser unit 1210 is located on the side of the second laser unit 1230 away from the second laser source 20, and the third laser unit 2100 is located on the side of the fourth laser unit 2120 away from the first laser source 10. That is, compared to the first laser unit 1210 and the third laser unit 2100, the second laser unit 1230 and the fourth laser unit 2120 are closer to the intersection of the first plane P1 and the second plane P2. Therefore, the arrangement of the laser sub-units in the first laser source 10 and the second laser source 20 in this embodiment is different.

[0054] Please see Figure 6 The first laser source 10 can be adopted Figure 5 The structure is as follows. Specifically, the first laser unit 1210, the second laser unit 1230, and the second laser module 140 are arranged at intervals in the first direction A1, and the third laser unit 2100, the fourth laser unit 2120, and the fourth laser module 230 are arranged at intervals in the first direction A1. In some other possible embodiments, the second laser unit 1230, the first laser unit 1210, and the second laser module 140 are arranged at intervals in the first direction A1, and the fourth laser unit 2120, the third laser unit 2100, and the fourth laser module 230 are arranged at intervals in the first direction A1.

[0055] In some other possible embodiments, the first laser module 120 and the second laser module 140 are spaced apart in the fourth direction B1, and the third laser module 210 and the fourth laser module 230 are spaced apart in the fifth direction B2. The fourth direction B1 is parallel to the first plane P1 and perpendicular to the second plane P2, and the fifth direction B2 is parallel to the second plane P2 and perpendicular to the first plane P1. It is easy to understand that the fourth direction B1 and the second designated direction H corresponding to the first laser source 10 are in the same direction, and the fifth direction B2 and the second designated direction H corresponding to the second laser source 20 are in the same direction.

[0056] Please see Figure 7 The first laser source 10 can be adopted Figure 3 or Figure 4The structure is as follows. Specifically, the second laser module 140 is located on the side of the first laser module 120 away from the designated axis (not shown in the figure), and the third laser module 210 is located on the side of the fourth laser module 230 away from the designated axis, which is the intersection of the first plane P1 and the second plane P2. In some other possible embodiments, the first laser module 120 is located on the side of the second laser module 140 away from the designated axis, and the fourth laser module 230 is located on the side of the third laser module 210 away from the designated axis, which is the intersection of the first plane P1 and the second plane P2. Specifically, the first laser L1 and the third laser L3 can jointly define the third laser reference plane, and the second laser L2 and the fourth laser L4 can jointly define the fourth laser reference plane, which intersects with the third laser reference plane.

[0057] exist Figure 7 In the illustrated embodiment, the first laser unit 1210 and the second laser unit 1230 are spaced apart on the sixth direction B3, which is parallel to the first plane P1 and perpendicular to the fourth direction B1. It is easy to understand that the sixth direction B3 is in the same direction as the aforementioned first designated direction W. The third laser unit 2100 and the fourth laser unit 2120 are spaced apart on the sixth direction B3. Specifically, the third sub-laser L31 and the first sub-laser L11 can jointly define the fifth laser reference plane, and the fourth sub-laser L32 and the second sub-laser L12 can jointly define the sixth laser reference plane. Figure 7 In the embodiment shown, the fifth laser reference plane and the sixth laser reference plane are parallel. Therefore, Figure 7 The laser sub-units in the first laser source 10 and the second laser source 20 are arranged in the same way. In some other possible embodiments, the fifth laser reference plane and the sixth laser reference plane may also intersect. For example, the first laser unit 1210 may be disposed above the second laser unit 1230, and the fourth laser unit 2120 may be disposed above the third laser unit 2100.

[0058] Please see Figure 8 The first laser source 10 can be adopted Figure 5 The structure is as follows. Specifically, the first laser unit 1210, the second laser unit 1230, and the second laser module 140 are arranged sequentially at intervals in the fourth direction B1. The third laser unit 2100, the fourth laser unit 2120, and the fourth laser module 230 are arranged sequentially at intervals in the fifth direction B2. In some other possible embodiments, the second laser unit 1230, the first laser unit 1210, and the second laser module 140 are arranged sequentially at intervals in the fourth direction B1. The fourth laser unit 2120, the third laser unit 2100, and the fourth laser module 230 are arranged sequentially at intervals in the fifth direction B2.

[0059] In this embodiment, the first polarization combining module 30 is disposed in the optical path where the first laser L1 and the third laser L3 are located. It is used to combine the polarization of one of the lasers, the first laser L1 and the third laser L3, with the other laser to generate the first mixed light H1.

[0060] In some possible embodiments, the first polarization combining module 30 may include a first polarization conversion unit 320 and a first polarization combining unit 340. The first polarization conversion unit 320 is disposed on the optical path of one of the first lasers L1 and L3, and is used to convert the polarization state of the laser incident on it to generate a first converted light. The first polarization combining unit 340 is disposed on the optical path of the other laser (L1 or L3) and the first converted light, and is used to perform polarization combining to generate a first mixed light H1.

[0061] For example, the first polarization conversion unit 320 can be disposed in the optical path of the first laser L1, and is used to convert the polarization state of the first laser L1, that is, to convert the P-polarized first laser L1 into the S-polarized first laser L1 (i.e., the first converted light). The first polarization combining unit 340 combines the S-polarized first laser L1 and the P-polarized third laser L3 to generate the first mixed light H1. As another example, the first polarization conversion unit 320 can be disposed in the optical path of the third laser L3, and is used to convert the polarization state of the third laser L3, that is, to convert the P-polarized third laser L3 into the S-polarized third laser L3 (i.e., the first converted light). The first polarization combining unit 340 combines the S-polarized third laser L3 and the P-polarized first laser L1 to generate the first mixed light H1.

[0062] Specifically, the first polarization conversion unit 320 can be a half-wave plate, and the first polarization combining unit 340 can be a polarization combining mirror. Please refer to [link / reference]. Figure 9 The first polarization combining unit 340 may include a first body 3410 and a first polarization layer 3430, wherein the first polarization layer 3430 is located on the surface of the first body 3410. The first polarization layer 3430 can be used to reflect laser light of a first polarization state and transmit laser light of a second polarization state, or the first polarization layer 3430 can be used to transmit laser light of a first polarization state and reflect laser light of a second polarization state. Specifically, the first polarization layer 3430 may be deposited on the surface of the first body 3410 using a coating process.

[0063] It should be noted that, since the first plane P1 and the second plane P2 are perpendicular to each other, the plane containing the first body 3410 needs to be tilted relative to the first plane P1 and the second plane P2. Specifically, the angle between the plane containing the first body 3410 and the first plane P1 is 45 degrees, and the angle between the plane containing the first body 3410 and the second plane P2 is 45 degrees. Therefore, in this embodiment, the incident angle of the laser is 45 degrees, which cannot meet the specified Brewster angle, meaning that the first polarization layer 3430 can only be used to transmit P-polarized laser light and reflect S-polarized laser light.

[0064] In this embodiment, the second polarization combining module 40 is disposed in the optical path where the second laser L2 and the fourth laser L4 are located. It is used to combine the polarization of one of the lasers, the second laser L2 and the fourth laser L4, with the other laser to generate the second mixed light H2.

[0065] In some possible embodiments, the second polarization combining module 40 may include a second polarization conversion unit 410 and a second polarization combining unit 430. The second polarization conversion unit 410 is disposed on the optical path of one of the second lasers L2 and L4, and is used to convert the polarization state of the laser incident on the second polarization conversion unit 410 to generate a second converted light. The second polarization combining unit 430 is disposed on the optical path of the other laser of the second laser L2 and L4 and the second converted light, and is used to perform polarization combining to generate a second mixed light H2.

[0066] For example, the second polarization conversion unit 410 can be disposed in the optical path of the second laser L2. It is used to convert the polarization state of the second laser L2, that is, to convert the S-polarized second laser L2 into a P-polarized second laser L2 (i.e., the second converted light). The second polarization combining unit 430 combines the P-polarized second laser L2 and the S-polarized fourth laser L4 to generate the second mixed light H2. Similarly, the second polarization conversion unit 410 can be disposed in the optical path of the fourth laser L4. It is used to convert the polarization state of the fourth laser L4, that is, to convert the S-polarized fourth laser L4 into a P-polarized fourth laser L4 (i.e., the second converted light). The second polarization combining unit 430 combines the P-polarized fourth laser L4 and the S-polarized second laser L2 to generate the second mixed light H2.

[0067] Specifically, the second polarization conversion unit 410 can be a half-wave plate, and the second polarization combining unit 430 can be a polarization combining mirror. Please refer to [link to relevant documentation]. Figure 10The second polarization combining unit 430 may include a second body 4320 and a second polarization layer 4340, wherein the second polarization layer 4340 is located on the surface of the second body 4320. The second polarization layer 4340 can be used to reflect laser light of a first polarization state and transmit laser light of a second polarization state, or it can be used to transmit laser light of a first polarization state and reflect laser light of a second polarization state. Specifically, the second polarization layer 4340 can be deposited on the surface of the second body 4320 using a coating process. It is easy to understand that, since the incident angle of the laser is 45 degrees, the specified Brewster angle cannot be met, meaning the second polarization layer 4340 can only be used to transmit laser light of the P-polarization state and reflect laser light of the S-polarization state.

[0068] This section describes the specific setup of the first polarization combining module 30 and the second polarization combining module 40, taking into account the specific placement of the first laser source 10 and the second laser source 20.

[0069] In some possible embodiments, the first laser source 10 and the second laser source 20 employ... Figure 2 or Figure 6 Arrange them in the manner described above. In this case, please refer to [the relevant documentation / reference]. Figure 1 The first polarization conversion unit 320 can be disposed in the optical path of the first laser L1, and the second polarization conversion unit 410 can be disposed in the optical path of the fourth laser L4. In this case, the two lasers emitted from the same laser source have the same polarization state; that is, the polarization state of the first laser L1 after conversion by the first polarization conversion unit 320 is the same as the polarization state of the second laser L2 (both are S-polarization states), and the polarization state of the fourth laser L4 after conversion by the second polarization conversion unit 410 is the same as the polarization state of the third laser L3 (both are P-polarization states). In some other possible embodiments, the first polarization conversion unit 320 can be disposed in the optical path of the third laser L3, and the second polarization conversion unit 410 can be disposed in the optical path of the second laser L2.

[0070] Since the two laser beams emitted from the same laser source have the same polarization state, when the first polarization layer 3430 and the second polarization layer 4340 are polarization layers with the same function, the two beams after polarization combining (i.e., the first mixed light H1 and the second mixed light H2) can be emitted in parallel, thereby reducing the difficulty of subsequent wavelength combining. Specifically, the first polarization layer 3430 and the second polarization layer 4340 can both be used to reflect the laser with the first polarization state and transmit the laser with the second polarization state. Alternatively, the first polarization layer 3430 and the second polarization layer 4340 can both be used to transmit the laser with the first polarization state and reflect the laser with the second polarization state. Therefore, when the first laser source 10 and the second laser source 20 adopt... Figure 2 or Figure 6When arranged in this manner, by placing the first polarization conversion unit 320 and the second polarization conversion unit 410 in front of different laser sources, the transmission and reflection characteristics of the first polarization combining unit 340 and the second polarization combining unit 430 can be made the same. For example, both can be used to transmit p and reflect s. This avoids the technical problem that when the transmission and reflection characteristics of the two polarization combining units are different, one polarization conversion unit needs to be set to transmit s and reflect p, which leads to high design difficulty and poor light combining effect. In other words, both polarization combining units are used to transmit p and reflect s, which can meet the specified Brewster angle and improve the polarization combining effect. Here, "transmit p and reflect s" means transmitting p-polarized light and reflecting s-polarized light.

[0071] In some possible embodiments, the first body 3410 and the second body 4320 can be coplanar. For example, the first body 3410 and the second body 4320 can be an integrally formed structure, that is, the first polarizing layer 3430 and the second polarizing layer 4340 can be deposited on the same substrate (e.g., a lens) to form the first polarizing beam combining unit 340 and the second polarizing beam combining unit 430 respectively, thereby reducing the hardware cost of the first polarizing beam combining unit 340 and the second polarizing beam combining unit 430. Alternatively, the first body 3410 and the second body 4320 can also be two different lenses, which can be coplanar or non-coplanar.

[0072] Specifically, the first polarizing layer 3430 and the second polarizing layer 4340 can be the same polarizing film, which is disposed on the surface of the same substrate (e.g., a lens) to form a polarization conversion mirror. Therefore, the names "first polarization combining unit 340 and second polarization combining unit 430" are for ease of description. In this embodiment, there is no clear dividing line between the two structures. That is, the part of the polarization conversion mirror used to form the first mixed light H1 can be regarded as the first polarization combining unit 340, and the part of the polarization conversion mirror used to form the second mixed light H2 can be regarded as the second polarization combining unit 430.

[0073] In some other possible embodiments, the first polarization layer 3430 and the second polarization layer 4340 can also be two different polarization films. For example, the first polarization layer 3430 can be used to transmit P-polarized blue-green laser light and reflect S-polarized blue-green laser light, while the second polarization layer 4340 can be used to transmit P-polarized red laser light and reflect S-polarized red laser light. Therefore, the two polarization films in this embodiment are determined based on the wavelengths of the two lasers to be polarized and combined, which can improve the combining efficiency of the polarized light to increase the energy of the first mixed light H1 and the second mixed light H2.

[0074] In some possible embodiments, the first laser source 10 and the second laser source 20 employ... Figure 2Arrange them in the manner described above. In this case, please refer to [the relevant documentation / reference]. Figure 1 The optical paths of the first sub-laser L11 and the fourth sub-laser L32 intersect in the first region 3410 of the first polarization combining unit 340, and the optical paths of the second sub-laser L12 and the third sub-laser L31 intersect in the second region 3430 of the first polarization combining unit 340. The second region 3430 and the first region 3410 do not overlap. The second region 3430 and the first region 3410 can be two adjacent regions or two non-adjacent regions within the first polarization combining unit 340; this embodiment does not impose a specific limitation. Therefore, Figure 2 In the embodiment shown, the first sub-laser L11 and the fourth sub-laser L32 of different colors achieve polarization combining in the same region of the first polarization combining unit 340, and the third sub-laser L31 and the second sub-laser L12 of different colors achieve polarization combining in another same region of the first polarization combining unit 340.

[0075] In some other possible embodiments, the optical paths of the first sub-laser L11 and the third sub-laser L31 intersect in the third region (not shown in the figure) of the first polarization combining unit 340, and the optical paths of the second sub-laser L12 and the fourth sub-laser L32 intersect in the fourth region (not shown in the figure) of the first polarization combining unit 340. The fourth region and the third region do not overlap. The fourth region and the third region can be two adjacent regions or two non-adjacent regions in the first polarization combining unit 340; this embodiment does not impose a specific limitation. Therefore, in this embodiment, the first sub-laser L11 and the third sub-laser L31 of the same color achieve polarization combining in the same region of the first polarization combining unit 340, and the second sub-laser L12 of the same color achieves polarization combining in another identical region of the first polarization combining unit 340. This embodiment can achieve coaxial combining of the same color by adjusting the placement of the laser units, thereby resulting in a smaller light spot after polarization combining, reducing the design difficulty and hardware cost of components in the subsequent optical path.

[0076] In some possible embodiments, the first laser source 10 and the second laser source 20 employ... Figure 6 The components are arranged in the manner described above. In this case, the first sub-laser L11 and the third sub-laser L31 can achieve coaxial polarization combining when polarized and combined on the first polarization combining unit 340; the second sub-laser L12 and the fourth sub-laser L32 can achieve coaxial polarization combining when polarized and combined on the first polarization combining unit 340; and the second laser L2 and the fourth laser L4 can achieve coaxial polarization combining when polarized and combined on the second polarization combining unit 430. This results in a smaller light spot after polarization combining, reducing the design difficulty and hardware cost of components in the subsequent optical path.

[0077] It is not difficult to understand here that, since the first laser source 10 and the second laser source 20 are arranged symmetrically in space, the optical path lengths of the first sub-laser L11, the second sub-laser L12, the third sub-laser L31 and the fourth sub-laser L32 to reach the first polarization combining unit 340 are approximately equal to the optical path lengths of the second laser L2 and the fourth laser L4 to reach the second polarization combining unit 430, thereby reducing the impact of changes in optical path length on the size of the light spot.

[0078] In some other possible embodiments, the first laser source 10 and the second laser source 20 employ... Figure 7 or Figure 8 The components are arranged in the manner described above. In this case, the first polarization conversion unit 320 can be placed in the optical path where the first laser L1 is located, and the second polarization conversion unit 410 can be placed in the optical path where the second laser L2 is located. Alternatively, please refer to... Figure 11 The first polarization conversion unit 320 can be disposed in the optical path where the third laser L3 is located, and the second polarization conversion unit 410 can be disposed in the optical path where the fourth laser L4 is located. Therefore, when the first laser source 10 and the second laser source 20 adopt... Figure 7 or Figure 8 When arranged in this manner, by placing the two polarization conversion units at the same laser source, the transmission and reflection characteristics of the first polarization combining unit 340 and the second polarization combining unit 430 can be made the same, for example, both transmitting p and reflecting s. This avoids the technical problem of high design difficulty and poor light combining effect when the polarization conversion characteristics of the two polarization combining units are different, requiring one polarization conversion unit to have a transmission and reflection characteristic of s and a reflection of p. In other words, both polarization combining units are used for transmission of p and reflection of s, which can meet the specified Brewster angle and improve the polarization combining effect. Here, "transmission of p and reflection of s" means transmitting p-polarized light and reflecting s-polarized light.

[0079] Specifically, the first polarization conversion unit 320 and the second polarization conversion unit 410 can be arranged coplanarly. For example, the first polarization conversion unit 320 and the second polarization conversion unit 410 can be integrally formed, that is, the first polarization conversion unit 320 and the second polarization conversion unit 410 are different parts on the same half-wave plate, thereby reducing the hardware cost of the first polarization conversion unit 320 and the second polarization conversion unit 410. Therefore, the names "first polarization conversion unit 320 and second polarization conversion unit 410" are for ease of description. In this embodiment, there is no clear dividing line between the two structures. That is, the part of the half-wave plate used to convert the polarization state of the third laser L3 can be regarded as the first polarization conversion unit 320, and the part of the half-wave plate used to convert the polarization state of the fourth laser L4 can be regarded as the second polarization conversion unit 410.

[0080] Because the first laser source 10 and the second laser source 20 in this embodiment adopt Figure 7 or Figure 8 The arrangement of the two mixed beams in the above manner makes the first mixed beam H1 and the second mixed beam H2 perpendicular to each other, thereby reducing the difficulty of subsequent wavelength combining.

[0081] In some possible embodiments, the first laser source 10 and the second laser source 20 employ... Figure 7 Arrange them in the manner described above. In this case, please refer to [the relevant documentation / reference]. Figure 11 The optical paths of the first sub-laser L11 and the third sub-laser L31 intersect in the fifth region 3450 of the first polarization combining unit 340, and the optical paths of the second sub-laser L12 and the fourth sub-laser L31 intersect in the sixth region 3470 of the first polarization combining unit 340. The sixth region 3470 and the fifth region 3450 do not overlap. The sixth region 3470 and the fifth region 3450 can be two adjacent regions or two non-adjacent regions within the first polarization combining unit 340; this embodiment does not impose a specific limitation. Therefore, Figure 11 In the illustrated embodiment, the first sub-laser L11 and the third sub-laser L31 of the same color achieve polarization combining in the same region of the first polarization combining unit 340, and the second sub-laser L12 and the fourth sub-laser L32 of the same color achieve polarization combining in another same region of the first polarization combining unit 340. When the second laser L2 and the fourth laser L4 perform polarization combining on the second polarization combining unit 430, they can achieve coaxial polarization combining. In this embodiment, the same-colored light rays achieve coaxial polarization combining, resulting in a smaller light spot after polarization combining, reducing the design difficulty and hardware cost of components in the subsequent optical path. Furthermore, in this embodiment, the laser sub-units in the first laser source 10 and the second laser source 20 are arranged in the same way. Two laser units with the same structure can be used in the optical path design, saving hardware costs for the light source device 100.

[0082] In some other possible embodiments, the optical paths of the first sub-laser L11 and the fourth sub-laser L32 intersect in the seventh region (not shown in the figure) of the first polarization combining unit 340, and the optical paths of the second sub-laser L12 and the third sub-laser L31 intersect in the eighth region (not shown in the figure) of the first polarization combining unit 340. The eighth region and the seventh region do not overlap. The eighth region and the seventh region can be two adjacent regions or two non-adjacent regions in the first polarization combining unit 340; this embodiment does not impose a specific limitation. Therefore, in this embodiment, the first sub-laser L11 and the fourth sub-laser L32, which are of different colors, achieve polarization combining in the same region of the first polarization combining unit 340, and the third sub-laser L31 and the second sub-laser L12, which are of different colors, achieve polarization combining in another identical region of the first polarization combining unit 340.

[0083] In some possible embodiments, the first laser source 10 and the second laser source 20 employ... Figure 8 The light source device 100 is arranged in the manner described above. In this case, the combining light path of the light source device 100 is as follows: Figure 12 As shown, a detailed introduction to the optical path of the combined light source can be found in the relevant explanations above, and will not be repeated here. From Figure 12 It is easy to see that, due to the symmetrical optical arrangement of the first laser source 10 and the second laser source 20 in space, the optical path lengths of the first sub-laser L11, second sub-laser L12, third sub-laser L31, fourth sub-laser L32, second laser L2, and fourth laser L4 reaching the wavelength combining module 50 are approximately equal, reducing the impact of changes in optical path length on the size of the light spot. Furthermore, the spot size of the emitted light O is approximately the same as the spot sizes of the first laser L1, second laser L2, third laser L3, and fourth laser L4, resulting in a smaller final emitted light spot size, reducing the design complexity and hardware cost of components in the subsequent optical path.

[0084] In this embodiment, the wavelength combining module 50 is disposed on the optical path where the first mixed light H1 and the second mixed light H2 are located. It is used to perform wavelength combining on the first mixed light H1 and the second mixed light H2 to generate outgoing light O.

[0085] In some possible embodiments, please refer again. Figure 1The first mixed light H1 and the second mixed light H2 are parallel. In this case, the wavelength combining module 50 may include a reflection unit 520 and a first wavelength combining unit 540. The reflection unit 520 is disposed on the optical path of one of the light rays in the first mixed light H1 and the second mixed light H2, and is used to reflect the light incident on the reflection unit 520 to generate reflected light. The first wavelength combining unit 540 is disposed on the optical path of the other light ray in the first mixed light H1 and the second mixed light H2 and the reflected light, and is used to perform wavelength combining to generate the outgoing light O.

[0086] For example, in Figure 1 In the illustrated embodiment, the reflection unit 520 is disposed in the optical path of the first mixed light H1, and is used to reflect the first mixed light H1 to the first wavelength combining unit 540. The first wavelength combining unit 540 is used to perform wavelength combining of the second mixed light H2 and the first mixed light H1 reflected by the reflection unit 520 to generate the outgoing light O. Alternatively, the reflection unit 520 is disposed in the optical path of the second mixed light H2, and is used to reflect the second mixed light H2 to the first wavelength combining unit 540. The first wavelength combining unit 540 is used to perform wavelength combining of the first mixed light H1 and the second mixed light H2 reflected by the reflection unit 520 to generate the outgoing light O.

[0087] Specifically, the reflecting unit 520 can be a reflector, and the first wavelength combining unit 540 can be a dichroic filter. For example, a film layer that transmits red light and reflects blue-green light can be deposited on the surface of the first wavelength combining unit 540 to transmit the second mixed light H2 and reflect the first mixed light H1 to generate outgoing light O. Alternatively, a film layer that reflects red light and transmits blue-green light can be deposited on the surface of the first wavelength combining unit 540 to reflect the second mixed light H2 and transmit the first mixed light H1 to generate outgoing light O. Specifically, researchers can flexibly adjust the placement of the reflecting unit 520 and the coating method of the first wavelength combining unit 540 according to the actual application scenario of the light source device 100; this embodiment does not impose specific limitations on this.

[0088] In other possible embodiments, please refer again. Figure 11 The first mixed light H1 and the second mixed light H2 are perpendicular to each other. In this case, the wavelength combining module 50 may include a second wavelength combining unit 560, which is disposed in the optical path containing the first mixed light H1 and the second mixed light H2, and is used to perform wavelength combining. Therefore, compared to Figure 1 The embodiment shown can reduce the number of reflection units, thereby saving hardware costs of the light source device 100.

[0089] Specifically, the second wavelength combining unit 560 can be a dichroic filter. For example, a film layer that transmits red light and reflects blue-green light can be deposited on the surface of the second wavelength combining unit 560 to transmit the second mixed light H2 and reflect the first mixed light H1 to generate the emitted light O. Alternatively, a film layer that reflects red light and transmits blue-green light can be deposited on the surface of the second wavelength combining unit 560 to reflect the second mixed light H2 and transmit the first mixed light H1 to generate the emitted light O. Specifically, researchers can flexibly adjust the coating method of the second wavelength combining unit 560 according to the actual application scenario of the light source device 100; this embodiment does not impose specific limitations on this.

[0090] Please see Figure 13 This application also provides an optical imaging system 900, which includes the aforementioned light source device 100. This system can be widely used in projection devices (e.g., micro projectors, short-throw projectors), laser TVs, engineering projectors, and laser video walls. Please refer to [link to relevant documentation]. Figure 13 The optical imaging system 900 may include a light source device 100, a lens module 910, a prism module 920, and a light modulator 930.

[0091] The light source device 100 is used to generate emitted light O. The specific structure of the light source device 100 can be found in the description in the above embodiments. The lens module 910 is disposed in the optical path of the emitted light O, serving to converge the emitted light O. Specifically, the lens module 910 may include a single lens or a lens group composed of multiple lenses. Since the emitted light O of the light source device 100 has a small spot size, the aperture and thickness of the lenses in the lens module 910 can be reduced, thereby reducing the design difficulty and hardware cost of the lens module 910.

[0092] A prism module 920 is disposed between the lens module 910 and the light modulator 930. It is used to reflect the emitted light O and focus it onto the light modulator 930. The light modulator 930 is used to modulate the light to form a beam carrying image information. The prism module 920 is also used to transmit the beam carrying image information through a projection area, such as a wall or projection screen.

[0093] Specifically, the optical modulator 930 can be a Digital Micromirror Device (DMD). The DMD is composed of an array of digital micromirrors, with each micromirror forming a modulation unit. Each modulation unit modulates the image corresponding to one pixel. Each micromirror flips under the drive signal generated by the controller. The number of flips of each micromirror is determined by the drive signal. The flipped micromirrors modulate the light reflected from the prism module 920, forming light carrying image information. In other possible embodiments, the optical modulator 930 can also be an HTPS LCD display chip, a reflective LCD device (LCOS), etc. This embodiment does not limit the specific implementation of the optical modulator 930.

[0094] This embodiment provides a light source device 100 and an optical imaging system 900 equipped with the light source device 100. The light source device 100 may include a first laser light source 10, a second laser light source 20, a first polarization combining module 30, a second polarization combining module 40, and a wavelength combining module 50. The first laser light source 10 may include a first laser module 120 and a second laser module 140. The first laser module 120 generates a first laser L1, which has a first polarization state. The second laser module 140 generates a second laser L2, which has a second polarization state. The first polarization state and the second polarization state are different. The first laser L1 and the second laser L2 are of different colors.

[0095] The second laser source 20 may include a third laser module 210 and a fourth laser module 230. The third laser module 210 generates a third laser L3, which has a first polarization state. The fourth laser module 230 generates a fourth laser L4, which has a second polarization state. The third laser L3 and the fourth laser L4 are of different colors.

[0096] The first polarization combining module 30 is disposed in the optical path containing the first laser L1 and the third laser L3. It is used to combine the polarization of one of the lasers, L1 and L3, with the other laser to generate a first mixed light H1. Since the two lasers have the same polarization state, the first polarization combining module 30 first changes the polarization state of one laser before combining it with the other. For example, it converts the P-polarized first laser L1 to an S-polarized state and then combines it with the P-polarized third laser L3 to generate the first mixed light H1. Because the P-polarized third laser L3 and the S-polarized first laser L1 can spatially compensate for each other, the resulting spot size of the first mixed light H1 is relatively small.

[0097] The second polarization combining module 40 is disposed in the optical path containing the second laser L2 and the fourth laser L4. It is used to combine the polarization of one of the lasers, L2 and L4, with the other laser to generate a second mixed light H2. Since the two lasers have the same polarization state, the second polarization combining module 40 first changes the polarization state of one laser before combining it with the other. For example, it converts the S-polarized fourth laser L4 to a P-polarized state and then combines it with the S-polarized second laser L2 to generate the second mixed light H2. Because the S-polarized second laser L2 and the P-polarized fourth laser L4 can spatially compensate for each other, the resulting second mixed light H2 has a smaller spot size.

[0098] A wavelength combining module 50 is disposed in the optical path containing the first mixed light H1 and the second mixed light H2. It is used to perform wavelength combining on the first mixed light H1 and the second mixed light H2 to generate the outgoing light O. Therefore, the light source device 100 in this embodiment uses a method of first polarization combining and then wavelength combining to combine multiple lasers, which can result in a smaller spot size of the final outgoing light O, reducing the design difficulty and hardware cost of components in the subsequent optical path.

[0099] Furthermore, since the multiple lasers in this embodiment have two different polarization states, the coherence of the laser can be weakened, thereby reducing the contrast of speckle in the laser, which is beneficial to improving the imaging quality of the optical imaging system equipped with the light source device 100.

[0100] In this application specification, certain terms are used to refer to specific components. Those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. The specification and claims do not distinguish components based on differences in name, but rather on differences in function. The term "comprising" throughout the specification and claims is an open-ended term and should be interpreted as "including but not limited to"; "generally" means that those skilled in the art can solve the technical problem within a certain margin of error and basically achieve the technical effect.

[0101] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "inside", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the purpose of simplifying the description of this application and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0102] In this application, unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or merely surface contact. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0103] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0104] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A light source device, characterized in that, include: The first laser source includes a first laser module and a second laser module. The first laser module is used to generate a first laser, and the polarization state of the first laser is a first polarization state. The second laser module is used to generate a second laser, and the polarization state of the second laser is a second polarization state. The first polarization state and the second polarization state are different, and the first laser and the second laser are of different colors. The second laser source includes a third laser module and a fourth laser module. The third laser module generates a third laser, the polarization state of which is the first polarization state. The fourth laser module generates a fourth laser, the polarization state of which is the second polarization state. The third laser and the fourth laser are of different colors. A first polarization combining module is disposed in the optical path where the first laser and the third laser are located. It is used to combine the polarization of one of the lasers, the first laser and the third laser, with the other laser after converting the polarization state to generate a first mixed light. The second polarization combining module is disposed in the optical path where the second laser and the fourth laser are located. It is used to combine the polarization of one of the lasers, the second laser and the fourth laser, with the other laser after converting the polarization state to generate a second mixed light. as well as A wavelength combining module is disposed on the optical path where the first mixed light and the second mixed light are located, and is used to perform wavelength combining on the first mixed light and the second mixed light to generate outgoing light.

2. The light source device according to claim 1, characterized in that, The first polarization combining module includes a first polarization conversion unit and a first polarization combining unit; The first polarization conversion unit is disposed on the optical path of one of the first lasers and the third laser, and is used to convert the polarization state of the laser incident on the first polarization conversion unit to generate the first converted light; The first polarization combining unit is disposed on the optical path of the other laser in the first laser and the third laser and the first converted light, and is used to perform polarization combining to generate the first mixed light; The second polarization combining module includes a second polarization conversion unit and a second polarization combining unit; The second polarization conversion unit is disposed on the optical path of one of the second lasers and the fourth laser, and is used to convert the polarization state of the laser incident on the second polarization conversion unit to generate the second converted light; The second polarization combining unit is disposed on the optical path of the other laser in the second laser and the fourth laser and the second converted light, and is used to perform polarization combining to generate the second mixed light.

3. The light source device according to claim 2, characterized in that, The first laser and the third laser are the same color, and the second laser and the fourth laser are the same color; The emission directions of the first laser and the second laser are perpendicular to the first plane; the emission directions of the third laser and the fourth laser are perpendicular to the second plane, and the first plane and the second plane are perpendicular to each other.

4. The light source device according to claim 3, characterized in that, The first laser module and the second laser module are spaced apart in a first direction, which is parallel to the first plane and the second plane, respectively. The third laser module and the fourth laser module are spaced apart in the first direction. The first laser and the third laser jointly define a first laser reference plane, and the second laser and the fourth laser jointly define a second laser reference plane. The first laser reference plane is parallel to the second laser reference plane.

5. The light source device according to claim 4, characterized in that, The first laser module includes a first laser unit and a second laser unit. The first laser unit is used to generate a first sub-laser, and the second laser unit is used to generate a second sub-laser. The wavelengths of the second laser, the first sub-laser, and the second sub-laser are different from each other. The third laser module includes a third laser unit and a fourth laser unit. The third laser unit is used to generate a third sub-laser, and the fourth laser unit is used to generate a fourth sub-laser. The third sub-laser is the same color as the first sub-laser, and the fourth sub-laser is the same color as the second sub-laser.

6. The light source device according to claim 5, characterized in that, The first laser unit and the second laser unit are spaced apart in a second direction, which is parallel to and perpendicular to the first plane. The third laser unit and the fourth laser unit are spaced apart in a third direction, which is parallel to the second plane and perpendicular to the first direction; The optical paths of the first sub-laser and the fourth sub-laser intersect in the first region of the first polarization combining unit, and the optical paths of the second sub-laser and the third sub-laser intersect in the second region of the first polarization combining unit. The second region and the first region do not overlap.

7. The light source device according to claim 5, characterized in that, The first laser unit and the second laser unit are spaced apart in a second direction, which is parallel to and perpendicular to the first plane. The third laser unit and the fourth laser unit are spaced apart in a third direction, which is parallel to the second plane and perpendicular to the first direction; The optical paths of the first sub-laser and the third sub-laser intersect in the third region of the first polarization combining unit, and the optical paths of the second sub-laser and the fourth sub-laser intersect in the fourth region of the first polarization combining unit. The fourth region and the third region do not overlap.

8. The light source device according to claim 5, characterized in that, The first laser unit, the second laser unit, and the second laser module are arranged at intervals in the first direction; The third laser unit, the fourth laser unit, and the fourth laser module are arranged at intervals in the first direction.

9. The light source device according to any one of claims 4 to 8, characterized in that, The first polarization conversion unit is disposed in the optical path where the first laser is located, and the second polarization conversion unit is disposed in the optical path where the fourth laser is located; or The first polarization conversion unit is disposed in the optical path of the third laser, and the second polarization conversion unit is disposed in the optical path of the second laser.

10. The light source device according to any one of claims 4 to 8, characterized in that, The first mixed light and the second mixed light are parallel to each other; The wavelength combining module includes a reflection unit and a first wavelength combining unit. The reflection unit is disposed on the optical path of one of the first mixed light and the second mixed light, and is used to reflect the light incident on the reflection unit to generate reflected light. The first wavelength combining unit is disposed on the optical path of the other light in the first mixed light and the second mixed light and the reflected light, and is used to perform wavelength combining.

11. The light source device according to claim 3, characterized in that, The first laser module and the second laser module are spaced apart in a fourth direction, which is parallel to the first plane and perpendicular to the second plane. The third laser module and the fourth laser module are spaced apart in a fifth direction, which is parallel to the second plane and perpendicular to the first plane.

12. The light source device according to claim 11, characterized in that, The second laser module is located on the side of the first laser module away from the designated axis, and the third laser module is located on the side of the fourth laser module away from the designated axis, where the designated axis is the intersection of the first plane and the second plane; or The first laser module is located on the side of the second laser module away from the designated axis, and the fourth laser module is located on the side of the third laser module away from the designated axis, which is the intersection of the first plane and the second plane.

13. The light source device according to claim 12, characterized in that, The first laser module includes a first laser unit and a second laser unit. The first laser unit is used to generate a first sub-laser, and the second laser unit is used to generate a second sub-laser. The wavelengths of the second laser, the first sub-laser, and the second sub-laser are different from each other. The third laser module includes a third laser unit and a fourth laser unit. The third laser unit is used to generate a third sub-laser, and the fourth laser unit is used to generate a fourth sub-laser. The third sub-laser is the same color as the first sub-laser, and the fourth sub-laser is the same color as the second sub-laser.

14. The light source device according to claim 13, characterized in that, The first laser unit and the second laser unit are spaced apart in a sixth direction, which is parallel to the first plane and perpendicular to the fourth direction; the third laser unit and the fourth laser unit are spaced apart in the sixth direction. The optical paths of the first sub-laser and the third sub-laser intersect in the fifth region of the first polarization combining unit, and the optical paths of the second sub-laser and the fourth sub-laser intersect in the sixth region of the first polarization combining unit. The sixth region and the fifth region do not overlap.

15. The light source device according to claim 13, characterized in that, The first laser unit and the second laser unit are spaced apart in a sixth direction, which is parallel to the first plane and perpendicular to the fourth direction; the third laser unit and the fourth laser unit are spaced apart in the sixth direction. The optical paths of the first sub-laser and the fourth sub-laser intersect in the seventh region of the first polarization combining unit, and the optical paths of the second sub-laser and the third sub-laser intersect in the eighth region of the first polarization combining unit. The eighth region and the seventh region do not overlap.

16. The light source device according to claim 13, characterized in that, The first laser unit, the second laser unit, and the second laser module are arranged at intervals in the fourth direction; The third laser unit, the fourth laser unit, and the fourth laser module are arranged sequentially at intervals in the fifth direction.

17. The light source device according to any one of claims 12 to 16, characterized in that, The first polarization conversion unit is disposed in the optical path where the first laser is located, and the second polarization conversion unit is disposed in the optical path where the second laser is located; or The first polarization conversion unit is disposed in the optical path of the third laser, and the second polarization conversion unit is disposed in the optical path of the fourth laser.

18. The light source device according to claim 17, characterized in that, The first polarization conversion unit and the second polarization conversion unit are arranged in the same plane.

19. The light source device according to any one of claims 12 to 16, characterized in that, The first mixed light and the second mixed light are perpendicular to each other. The wavelength combining module includes a second wavelength combining unit, which is disposed on the optical path where the first mixed light and the second mixed light are located, and is used to perform wavelength combining.

20. The light source device according to claim 2, characterized in that, The first polarization combining unit includes a first body and a first polarization layer, the first polarization layer being located on the surface of the first body; the second combining conversion unit includes a second body and a second polarization layer, the second polarization layer being located on the surface of the second body; Both the first polarization layer and the second polarization layer are used to reflect laser light of the first polarization state and transmit laser light of the second polarization state; or Both the first polarization layer and the second polarization layer are used to transmit laser light of the first polarization state and reflect laser light of the second polarization state.

21. An optical imaging system, characterized in that, include: The light source device according to any one of claims 1 to 20, wherein the light source device is used to generate emitted light; as well as An optical modulator is disposed in the optical path of the emitted light.

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