Laser light source

Abstract

The embodiment of the invention belongs to the laser display technology, and provides a laser light source which comprises a plurality of light-emitting chips and a plurality of collimating lenses corresponding to the light-emitting chips. The light-emitting chip comprises a plurality of light-emitting points, the light-emitting points are used for emitting laser in the third direction, and the diffusion angle of the laser in the first direction is smaller than the diffusion angle of the laser in the second direction; the collimating lenses are located on the light-emitting sides of the corresponding light-emitting chips and used for collimating the laser in the first direction before light spots corresponding to the laser emitted by the multiple light-emitting points in the light-emitting chips are overlapped. The laser in the first direction can be collimated, the collimation degree of the laser in the first direction is improved, meanwhile, separation of light spots corresponding to the laser emitted by the multiple light-emitting points is achieved, for a projection system comprising the diffractive optical element, the efficiency of the diffractive optical element is improved, and then the efficiency of the projection system is improved; and meanwhile, the overlarge light spot size is avoided, and the design difficulty of a subsequent optical system is reduced.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to laser display technology. More particularly, to a laser light source. BACKGROUND

[0002] The laser light source has the advantages of good monochromaticity, high brightness, long service life, etc., and is an ideal light source, which is widely used in projection systems.

[0003] In some related technologies, the laser light source can include a light emitting chip and a lens corresponding to the light emitting chip. The light emitting chip includes a plurality of light emitting points, each of which can emit laser light, and the lens is used to collimate the laser light in the fast axis direction.

[0004] Since the lens only collimates the laser light in the fast axis direction, the laser light in the slow axis direction is not collimated, resulting in low collimation of the laser light in the slow axis direction. For a projection system including a diffractive optical element (DOE), the low collimation light beam is irradiated onto the DOE, resulting in low diffraction efficiency of the DOE. At the same time, since the slow axis direction is not collimated, the light spots corresponding to the laser light emitted by the plurality of light emitting points will overlap or coincide, and the overlapping or coinciding light spots irradiated onto the DOE can cause interference effect, also resulting in low diffraction efficiency of the DOE, thereby resulting in low efficiency of the projection system. SUMMARY

[0005] Embodiments of the present application provide a laser light source, which can be used to solve the problem in the related art that since the lens only collimates the laser light in the fast axis direction, the laser light in the slow axis direction is not collimated, the low collimation light beam is irradiated onto the DOE, resulting in low diffraction efficiency of the DOE. At the same time, since the slow axis direction is not collimated, the light spots corresponding to the laser light emitted by the plurality of light emitting points will overlap or coincide, and the overlapping or coinciding light spots irradiated onto the DOE can cause interference effect, also resulting in low diffraction efficiency of the DOE, thereby resulting in low efficiency of the projection system.

[0006] In a first aspect, embodiments of the present application provide a laser light source, which includes a plurality of light emitting chips and a plurality of collimating lenses corresponding to the plurality of light emitting chips.

[0007] The light emitting chip includes a plurality of light emitting points, and the light emitting points are used to emit laser light along a third direction. The divergence angle of the laser light in a first direction is smaller than the divergence angle of the laser light in a second direction. The first direction is perpendicular to the second direction, and the first direction and the second direction are perpendicular to the third direction.

[0008] The collimating lens is located at the light emitting side of the corresponding light emitting chip, and is used for collimating the laser in the first direction before the light spots corresponding to the laser emitted by the plurality of light emitting points in the light emitting chip overlap.

[0009] In some embodiments of the present application, the distance between the light emitting chip and the collimating lens ranges from greater than or equal to 0.15 mm and / or less than or equal to 0.4 mm.

[0010] In some embodiments of the present application, the collimating lens comprises a plurality of first collimating components corresponding to the light emitting points, and each first collimating component comprises a first surface which is a curved surface and is used for collimating the laser in the first direction.

[0011] In some embodiments of the present application, the radius of curvature of the first surface ranges from greater than or equal to -1 mm and / or less than or equal to 1 mm.

[0012] In some embodiments of the present application, the thickness of the first collimating component ranges from greater than or equal to 0.1 mm and / or less than or equal to 0.3 mm.

[0013] In some embodiments of the present application, the thickness of the first collimating component is the distance between the center of the first surface and a second surface, and the second surface is a plane opposite to the first surface in the first collimating component.

[0014] In some embodiments of the present application, the collimating lens further comprises a second collimating component, and the second collimating component comprises a third surface which is a curved surface and is used for collimating the laser in the second direction.

[0015] In some embodiments of the present application, the radius of curvature of the third surface ranges from greater than or equal to -1 mm and / or less than or equal to 1 mm.

[0016] In some embodiments of the present application, the thickness of the second collimating component ranges from greater than or equal to 0.2 mm and / or less than or equal to 0.6 mm.

[0017] In some embodiments of the present application, the laser light source further comprises a cover plate located at the light emitting side of the collimating lens, and the thickness of the cover plate ranges from greater than or equal to 0.5 mm and / or less than or equal to 1 mm.

[0018] In some embodiments of the present application, the laser light source further comprises a lens assembly located at the light emitting side of the cover plate and used for shaping the laser emitted by the cover plate or collimating the laser in the second direction emitted by the cover plate.

[0019] The application provides a laser light source, which comprises a plurality of light emitting chips and collimating lenses corresponding to the light emitting chips. The light emitting chip comprises a plurality of light emitting points, the light emitting points are used to emit laser light along a third direction, and the divergence angle of the laser light in a first direction is smaller than the divergence angle of the laser light in a second direction. The collimating lens can collimate the laser light in the first direction before the light spots corresponding to the laser light emitted by the plurality of light emitting points overlap. For a projection system comprising a DOE, the collimation degree of the laser light incident on the DOE is improved, which is beneficial to improving the diffraction efficiency of the DOE. At the same time, since the collimation degree of the laser light in the first direction is high, the light spots corresponding to the laser light emitted by the plurality of light emitting points will not overlap with the increase of the optical path, and the separation of the light spots is realized. Compared with the plurality of overlapping light spots incident on the DOE, the plurality of separated light spots incident on the DOE is beneficial to improving the diffraction efficiency of the DOE, and then is beneficial to improving the efficiency of the projection system. Since the laser light in the first direction is collimated, the beam quality is also improved, the size of the light spot is avoided to be too large, and the design difficulty of the subsequent optical system is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the application or the implementation manners in the related art, the drawings needed to be used in the embodiments or the related art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0021] Figure 1 A laser package structure provided by the embodiment of the application Figure 1 ;

[0022] Figure 2 A laser package structure provided by the embodiment of the application Figure 2 ;

[0023] Figure 3 An internal structure of a laser provided by the embodiment of the application Figure 1 ;

[0024] Figure 4 An internal structure of a laser provided by the embodiment of the application Figure 2 ;

[0025] Figure 5 A schematic diagram of laser light in the fast-axis direction corresponding to a single light emitting point

[0026] Figure 6 A schematic diagram of laser light in the slow-axis direction corresponding to a single light emitting point

[0027] Figure 7 A schematic diagram of laser light in the fast-axis direction corresponding to a double light emitting point

[0028] Figure 8 A schematic diagram of a laser in a slow axis direction corresponding to a double light emitting point;

[0029] Figure 9 A structure schematic of a laser light source provided by an embodiment of the present application Figure 1 ;

[0030] Figure 10 A schematic diagram of a double light emitting point light emitting chip provided by an embodiment of the present application

[0031] Figure 11 A collimation process schematic of a multi-light emitting point emitted laser in a slow axis direction provided by an embodiment of the present application

[0032] Figure 12 A structure schematic of a collimation lens provided by an embodiment of the present application Figure 1 ;

[0033] Figure 13 A schematic diagram of a laser collimated in a slow axis direction based on a first collimation component provided by an embodiment of the present application

[0034] Figure 14 A schematic diagram of a light spot shape after a laser collimated in a slow axis direction based on a first collimation component provided by an embodiment of the present application

[0035] Figure 15 A structure schematic of a collimation lens provided by an embodiment of the present application Figure 2 ;

[0036] Figure 16 A side view of a collimation lens provided by an embodiment of the present application

[0037] Figure 17 A top view of a collimation lens provided by an embodiment of the present application

[0038] Figure 18 A schematic diagram of a laser collimated in a fast axis direction based on a second collimation component provided by an embodiment of the present application

[0039] Figure 19 A schematic diagram of a light spot shape after a laser collimated in a fast axis direction based on a second collimation component provided by an embodiment of the present application

[0040] Figure 20 A structure schematic of a laser light source provided by an embodiment of the present application Figure 2 ;

[0041] Figure 21 A structure schematic of a display device provided by an embodiment of the present application Figure 1;

[0042] Figure 22 A structure schematic of a display device provided by an embodiment of the present application Figure 2 . DETAILED DESCRIPTION

[0043] For the purpose of making the objectives, implementations and advantages of the present application clearer, the following will combine the drawings in the exemplary embodiments of the present application to make a clear and complete description of the exemplary implementations of the present application. Obviously, the described exemplary embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application.

[0044] It should be noted that the brief description of the terms in the present application is only for the convenience of understanding the following described embodiments, and is not intended to limit the implementations of the present application. Unless otherwise specified, these terms should be understood according to their ordinary and general meanings.

[0045] In addition, the terms "include" and "have" and any variations thereof are intended to cover but not exclusive inclusion, for example, a product or device including a series of components does not have to be limited to the clearly listed components, but can include other components that are not clearly listed or inherent to these products or devices.

[0046] Laser light source has the advantages of good monochromaticity, high brightness, long service life, etc., and is a relatively ideal light source. With the improvement of the power of laser devices, the requirements of industrial application are met, and the laser is gradually used as a light source for illumination. In recent years, lasers are used as projection light sources in projection equipment, gradually replacing mercury lamp illumination, and compared with LED light sources, lasers have been widely used due to their small optical expansion and high brightness.

[0047] Figure 1 A laser packaging structure provided by an embodiment of the present application Figure 2 , Figure 3 A laser packaging structure provided by an embodiment of the present application Figure 1 , as shown in Figure 4 and Figure 2 , the welding base 101 can be welded to the tube shell seat 102 on one side, and can print a circuit board inside the welding base 101 to realize the circuit interconnection function with the tube shell seat 102.

[0048] The tube shell seat 102 can be fixed with the welding base 101 by reflow soldering with tin-silver-copper alloy, and the welding method is not limited to the same flow welding, but can also be achieved by high-temperature pressure sintering silver paste and copper paste. The material of the welding base 101 can be oxygen-free copper, diamond copper and other metal materials.

[0049] Figures 2 to 4A schematic diagram of the internal structure of a laser provided in this application embodiment. Figure 1 , Figure 2 A schematic diagram of the internal structure of a laser provided in this application embodiment. Figure 1 , combined Figure 2 As shown, the light-emitting unit 105 includes a heat sink and a light-emitting chip. The light-emitting chip is soldered onto the heat sink using a eutectic process. The main materials of the heat sink are AlN (aluminum nitride) and SiC (silicon carbide). The waveguide dimension in the vertical direction of the light-emitting unit 105 is relatively small, resulting in a large divergence angle while maintaining near-diffraction-limited beam quality. Therefore, this direction is defined as the fast axis. Depending on the waveguide layer size along the fast axis, the beam divergence angle ranges from 40° to 60°. The horizontal direction of the light-emitting unit 105 is the slow axis, with the active region typically ranging from 100μm to 500μm in size and a divergence angle of 6° to 15°, exhibiting poor beam quality.

[0050] The emitted light beam from the light-emitting unit 105 passes through the reflector 106, which refracts the beam back by 90°. The reflector 106 can be made of materials such as borosilicate glass, quartz, or silicon, and its surface is coated with an anti-reflection film to improve reflectivity. Because the divergence angle of the light-emitting unit 105 along its fast axis is relatively large, the reflector 106 can only refract most of the light beam emitted from the light-emitting unit 105. The remaining portion of the beam does not form effective light but instead exits from the side of the reflector 106, forming stray beams.

[0051] Figure 3 and Figure 3 The cover plate 103 shown primarily serves to ensure the airtightness of the housing 102. The cover plate 103 can be made of high-strength sapphire or glass, among other materials. The cover plate 103 has a metal layer around its perimeter, with the remainder being a light-transmitting area. The metal layer, combined with solder, achieves a high airtightness level. Alloy solder is added to the metal layer around the cover plate 103 to ensure a tight weld between the cover plate 103 and the housing 102. The thickness of the solder layer is related to the surface smoothness of the welding area of ​​the housing 102. The alloy solder, after melting at a temperature above its melting point, fills the welding area. If the thickness of the alloy solder is less than the surface smoothness of the welding area, the solder cannot completely fill the welding area, resulting in poor airtightness.

[0052] Figure 4 and Figure 1The lens 104 shown in FIG. 1 is mainly used to process the divergence angle of the light beam emitted by the light emitting unit 105, and thus the lens 104 needs to be designed and optimized according to the divergence angle of the light emitting unit 105 and the optical path parameters of the light emitting device. Therefore, the curvature of the lens 104 can be optimized according to the different characteristics of each light emitting unit 105, or the lens 104 can be optimized to have the same curvature according to the portability and cost of processing. The surface type of the lens 104 can be optimized to be aspherical, free-form surface, or material Fresnel structure to realize the function of compressing the divergence angle.

[0053] In addition to the above-mentioned devices, the laser can also include Figure 2 The 1021 shown in FIG. 1 is used to represent the side wall of the tube shell seat, Figures 5 to 8 And Figure 5 The 1022 shown in FIG. 1 is used to represent the step of the side wall of the tube shell seat.

[0054] With the development of the field of laser display, the requirement for the power of the laser is gradually increasing. In order to improve the power level, some blue-green chips and most visible red chips adopt a design of double light emitting points or multiple light emitting points. The main difference between the red chip and the blue-green chip lies in the size of the light emitting point and the distance between the light emitting points.

[0055] In some related technologies, the laser emitted by the light emitting chip is collimated, which is usually realized by arranging a collimating lens outside the laser packaging module. The collimating lens is Figure 6 And Figure 7 The lens 104 shown in FIG. 1.

[0056] However, since the collimating lens is usually used to collimate the laser in the fast-axis direction, it does not collimate the laser in the slow-axis direction. For the light emitting chip including multiple light emitting points, the distance between the light emitting points is relatively close, generally between 100 microns and 300 microns, and the distance to the collimating lens in the packaging generally needs to be 3-10 mm, which can be designed according to actual requirements. However, since the distance between the light emitting chip and the collimating lens is far, the light spots corresponding to the multiple light emitting points have already overlapped before reaching the collimating lens, and for the multiple light emitting points, the two are eccentric designs, which are difficult to collimate.

[0057] For the optical system including the DOE, the light beam with low collimation degree irradiated on the DOE will result in low diffraction efficiency of the DOE. At the same time, since the laser is not collimated in the slow-axis direction, the light beams emitted by the multiple light emitting points will overlap or coincide, and the multiple overlapping light spots irradiated on the DOE may have interference effect, further resulting in low diffraction efficiency of the DOE. Since the diffraction efficiency of the DOE is low, the efficiency of the projection system is also low.

[0058] Meanwhile, compared with the single light emitting chip, with the increase of the light path, the divergence angle of the laser increases, and when the multi-chip is packaged, with the increase of the number of chips, the overall light spot size becomes large, which increases the design difficulty of the subsequent optical system.

[0059] Specifically, refer to Figure 8 as shown in the figure, Figures 5 to 8 is a schematic diagram of laser in the fast axis direction corresponding to a single light emitting point, Figure 5 is a schematic diagram of laser in the slow axis direction corresponding to a single light emitting point, Figure 6 is a schematic diagram of laser in the fast axis direction corresponding to a double light emitting point, Figure 7 is a schematic diagram of laser in the slow axis direction corresponding to a double light emitting point. Figure 8 In the figure, 50 is used to represent the light emitting chip, 501 represents the light emitting point, and 60 represents the collimating lens, which is used to collimate the laser in the fast axis direction.

[0060] For the single light emitting point of the light emitting chip included in the laser, Figure 9 As can be seen from the figure, since the collimation degree of the laser in the fast axis direction is high, with the increase of the distance, the size of the light spot corresponding to the laser in the fast axis direction basically does not change. However, Figure 1 As can be seen from the figure, for the slow axis direction, since the laser is not collimated in the slow axis direction, the size of the light spot corresponding to the laser gradually increases with the increase of the distance.

[0061] Compared with the single light emitting point, when the light emitting chip included in the laser is a double light emitting point, Figure 9 As can be seen from the figure, since the laser is collimated in the fast axis direction, the size of the light spot corresponding to the laser in the fast axis direction also basically does not change, but Figure 9 As can be seen from the figure, at this time, since the laser is not collimated in the slow axis direction, compared with the single light emitting point, the size of the light spot corresponding to the laser significantly increases with the increase of the distance, and a certain overlap will also be generated.

[0062] Based on this, the application provides a kind of laser light source.For laser light source, since the distance between multiple light emitting points included by light emitting chip is small, then with the increase of optical path, facula generates overlap or coincidence, at this time, it is difficult to collimate, therefore if getting the facula of higher collimation degree and separation, need to develop lens built-in process, set the lens capable of collimating slow axis at the exit position of light emitting chip, reduce the divergence angle of slow axis, therefore, the laser light source of the application includes collimating lens located at the light emitting side of light emitting chip, can collimate slow axis, not only can get the light beam of higher collimation degree, also can avoid the facula corresponding to the laser emitted by multiple light emitting points to generate overlap, get separated facula.For the projection system including DOE, it can meet the design requirements of DOE needing facula independence and the requirements of higher collimation degree of incident light beam, improve the efficiency of DOE, and then improve the efficiency of system.At the same time, it also avoids facula size too large, reduces the difficulty of subsequent optical system design.

[0063] The technical solutions of the application will be described in detail below with specific embodiments.The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in some embodiments.

[0064] Figure 9 The structure of a laser light source provided in the embodiments of the application Figure 10 , as shown in Figure 10 , the laser light source 90 includes: a plurality of light emitting chips 901 and a plurality of collimating lenses 902 corresponding to the plurality of light emitting chips 901;

[0065] The light emitting chip 901 includes a plurality of light emitting points, and the light emitting points are used to emit laser along a third direction, and the divergence angle of the laser in a first direction is smaller than the divergence angle of the laser in a second direction, the first direction is perpendicular to the second direction, and the first direction and the second direction are perpendicular to the third direction;

[0066] The collimating lens 902 is located at the light emitting side of the corresponding light emitting chip 901, and is used to collimate the laser in the first direction before the facula corresponding to the laser emitted by the plurality of light emitting points in the light emitting chip 901 generates overlap.

[0067] In an implementation scenario, the plurality of light emitting chips 901 included by the laser light source 90 can include light emitting chips emitting one or more colors of laser, such as light emitting chips emitting red laser, light emitting chips emitting green laser, light emitting chips emitting blue laser, etc., and the number and arrangement of the light emitting chips 901 are not limited by the application.

[0068] As shown in Figure 10 , in addition to the light emitting chip 901 and the collimating lens 902, Figure 10The image also shows a reflective device 903. The laser emitted from the light-emitting chip 901 is collimated by the collimating lens 902 and then incident on the reflective device 903. After being reflected by the reflective device 903, it is emitted outward.

[0069] Each light-emitting chip 901 may include multiple light-emitting points. The number of light-emitting points may be two, three, etc. Typically, the distance between light-emitting points is greater than or equal to 100 micrometers and / or less than or equal to 300 micrometers. This application does not limit the number and distance of light-emitting points.

[0070] Since the diffusion angle of the laser emitted from the light source in the first direction is smaller than that in the second direction, the first direction is the slow axis direction and the second direction is the fast axis direction.

[0071] In one implementation scenario, the light-emitting chip 901 includes multiple light-emitting points that can be arranged along the slow axis direction. Figure 11 This is a schematic diagram of a dual-light-emitting chip provided in an embodiment of this application. Figure 11 The illustrated light-emitting chip 901 includes two light-emitting points, P1 and P2, which are arranged along the slow axis direction. Figure 11 The X-direction shown is the fast axis direction. Figure 11 The Y direction is shown.

[0072] In one implementation scenario, the collimating lens 902 corresponds one-to-one with the light-emitting chip 901, so the number of collimating lenses 902 is the same as the number of light-emitting chips 901.

[0073] In one implementation scenario, the collimating lens 902 can be made of glass BK7 and can be manufactured using a one-piece molding method.

[0074] Since multiple emission points are arranged along the slow axis, the laser spots emitted from these points will overlap or coincide along the slow axis. Therefore, a collimating lens 902 can be used to collimate the laser beams along the slow axis before the overlapping occurs, reducing the divergence angle in the slow axis direction. After collimation, as the optical path increases, the laser spots emitted from the multiple emission points remain separate spots and no longer overlap. For details, please refer to [reference needed]. Figure 12 As shown. Figure 1 This is a schematic diagram illustrating the collimation process of a multi-emitting laser in the slow axis direction, as provided in an embodiment of this application. Figure 12 The 904 shown is a cover plate, made of Figure 12 As can be seen, the laser in the slow axis direction remains collimated after passing through the cover plate 904. The position and function of the cover plate 904 can be referred to the following embodiment, which will not be described in detail here.

[0075] In an implementation scenario, the collimating lens 902 can collimate the laser light in the slow-axis direction and the fast-axis direction, which is beneficial to improve the beam quality of the laser light emitted by the laser light source 90, and also avoids the increase of the size of the light spot and reduces the design difficulty of the subsequent optical system.

[0076] When the collimating lens 902 can collimate the laser light in the fast-axis direction and the slow-axis direction, the order of collimating the laser light in the fast-axis direction and the slow-axis direction is not limited, and it is only required to collimate the laser light in the slow-axis direction before the laser light emitted by the multiple light emitting points overlaps.

[0077] In some embodiments, in order to make the collimating lens 902 collimate the laser light in the slow-axis direction before the laser light emitted by the multiple light emitting points overlaps to obtain multiple separated light spots, the distance between the light emitting chip 901 and the collimating lens 902 can be limited. In an implementation scenario, the distance between the light emitting chip 901 and the collimating lens 902 is greater than or equal to 0.15 mm and / or less than or equal to 0.4 mm.

[0078] Since the divergence angle of the laser light in the fast-axis direction and the slow-axis direction increases with the increase of the distance between the light emitting chip 901 and the collimating lens 902, the effective aperture of light collection increases, which leads to the increase of the packaging volume of the laser light source 90, the distance between the light emitting chip 901 and the collimating lens 902 can be greater than or equal to 0.15 mm and / or less than or equal to 0.4 mm, and the specific distance can be set according to actual requirements, for example, it can be 0.2 mm.

[0079] In another implementation scenario, the light emitting chip 901 is fixed on a heat sink, and the heat sink is fixed on a bottom plate. Generally, the heat sink can be bonded to the bottom plate by an adhesive, and the adhesive may overflow around during bonding. Based on the above range of the distance between the light emitting chip 901 and the collimating lens 902, when the distance between the light emitting chip 901 and the collimating lens 902 is too short, the adhesive may stick to the collimating lens 902.

[0080] In another implementation scenario, based on the above range of the distance between the light emitting chip 901 and the collimating lens 902, when the distance between the light emitting chip 901 and the collimating lens 902 is too long, the size of the light spot corresponding to the laser light gradually increases with the increase of the optical path, and at this time, the size of the collimating lens 902 also needs to be increased, which leads to the large volume of the laser light source 90.

[0081] Meanwhile, as the distance between the light emitting chip 901 and the collimating lens 902 is further lengthened, the laser light emitted by the multiple light emitting points will overlap before being incident on the collimating lens 902, which reduces the collimating effect of the collimating lens 902 on the laser light emitted by the multiple light emitting points, and the collimating degree is poor.

[0082] It should be noted that the laser light source 90 of the present application can be applied in different types of multi-chip packages, including but not limited to metal, ceramic, etc.

[0083] The embodiment of the present application provides a laser light source 90, which comprises a plurality of light emitting chips 901 and a plurality of collimating lenses 902 corresponding to the plurality of light emitting chips 901. Wherein, the light emitting chip 901 comprises a plurality of light emitting points, each light emitting point is used for emitting laser light along a third direction, and the diffusion angle of the laser light in a first direction is smaller than the diffusion angle in a second direction. The collimating lens 902 is used for collimating the laser light in the first direction before the light spots corresponding to the laser light emitted by the multiple light emitting points overlap, which improves the collimating degree of the laser light in the first direction. For the projection system comprising a DOE, the laser light with high collimating degree is irradiated on the DOE, which effectively improves the diffraction efficiency of the DOE, and further improves the efficiency of the projection system. At the same time, since the collimating degree of the laser light in the first direction is high, the divergence angle of the laser light in the first direction is reduced, so that after collimation, the light spots corresponding to the laser light emitted by the multiple light emitting points no longer overlap, the separation of the light spots is realized, and the separated light spots are irradiated on the DOE, which is beneficial to further improve the diffraction efficiency of the DOE. Since the laser light in the first direction is collimated, the beam quality is also improved, which avoids the size of the light spot being too large, thereby reducing the design difficulty of the subsequent optical system.

[0084] Figure 13 A structure diagram of a collimating lens provided in the embodiment of the present application Figure 13 , as shown in Figure 14 , in one or more embodiments of the present application, the collimating lens 902 comprises a plurality of first collimating components 9021, the first collimating component 9021 corresponds to the light emitting point, comprising a first surface S1, the first surface S1 is a curved surface, used for collimating the laser light in the first direction.

[0085] The number of first collimating components 9021 is the same as the number of light emitting points included in the light emitting chip 901, Figure 14 The collimating lens 902 shown in

[0086] The distance between the light emitting chip 901 and the collimating lens 902 is the distance between the light emitting chip 901 and the center of the first surface S1 in the first collimating component 9021.

[0087] The first direction is still used to represent the slow axis direction. In one implementation scenario, if the laser in the slow axis direction is collimated first, and then the laser in the fast axis direction is collimated, the first surface S1 is located on the side close to the light emitting chip 901. In another implementation scenario, if the laser in the fast axis direction is collimated first, and then the laser in the slow axis direction is collimated, the first surface S1 is located on the side away from the light emitting chip 901.

[0088] Figure 14 A schematic diagram of collimating laser in the slow axis direction based on the first collimating component provided by the embodiments of the present application is still illustrated by taking the double light emitting point light emitting chip 901 as an example, which comprises Figure 15 It can be known that the laser emitted by the light emitting point is collimated in the slow axis direction after passing through the first collimating component 9021, and a light beam with high collimation degree is obtained.

[0089] Figure 15 A schematic diagram of the shape of the light spot after collimating laser in the slow axis direction based on the first collimating component provided by the embodiments of the present application is illustrated, wherein the circular area can be used to represent the receiving surface, and the dotted area can be used to represent the light spot, which comprises Figure 2 It can be known that two separate light spots are presented on the receiving surface at this time, and the two light spots do not overlap.

[0090] Figure 12 The 0.2600 millimeter shown in the above formula is used to define the size of the receiving surface, and in one implementation scenario, the size of the receiving surface can be used to determine the size of the current light spot.

[0091] In another implementation scenario, if the light emitting chip 901 comprises three light emitting points, the number of the first collimating component 9021 is three, and the specific implementation can be referred to Figure 12 , Figure 12 A structure schematic diagram of the collimating lens provided by the embodiments of the present application is illustrated Figure 12 .

[0092] In some embodiments, the radius of curvature of the first surface S1 ranges from greater than or equal to -1 mm and / or less than or equal to 1 mm.

[0093] In one implementation scenario, the first surface S1 can be provided by a cylindrical lens.

[0094] In an implementation scenario, when the curvature radius of the first surface S1 is greater than or equal to -1 mm and / or less than or equal to 1 mm, the collimation of the laser in the slow axis direction can be effectively performed, and the collimation degree is high. Based on the curvature radius range of the first surface S1, the curvature radius of the first surface S1 can be determined according to the distance between the light emitting chip 901 and the collimation lens 902 and the thickness of the collimation lens 902 and the like. For example, the curvature radius of the first surface S1 can be set to 0.103 mm.

[0095] In another implementation scenario, based on the curvature radius range of the first surface S1, when the curvature radius of the first surface S1 is too large or too small, the collimation degree of the laser in the slow axis direction is reduced, and the collimation effect is affected.

[0096] In some embodiments, the thickness of the first collimation component 9021 ranges from greater than or equal to 0.1 mm and / or less than or equal to 0.3 mm.

[0097] The thickness of the first collimation component 9021 is the distance between the center of the first surface S1 and the second surface, and the second surface is the plane in the first collimation component 9021 opposite to the first surface S1.

[0098] Still referring to Figure 16 , the second surface is S2 shown in Figure 17 , and the thickness of the first collimation component 9021 is d1 shown in Figure 12 .

[0099] In an implementation scenario, when the thickness of the slow axis collimation lens is greater than or equal to 0.1 mm and / or less than or equal to 0.3 mm, not only is the first collimation component 9021 prevented from being too thick, which is beneficial to the miniaturization of the laser light source 90, but also the processing difficulty of the collimation lens 902 is reduced.

[0100] In another implementation scenario, based on the thickness range of the first collimation component 9021, when the thickness of the first collimation component 9021 is too large, the volume of the collimation lens 902 is increased, which is not conducive to the miniaturization of the laser light source 90, and also increases the processing difficulty of the collimation lens 902.

[0101] In another implementation scenario, based on the thickness range of the first collimation component 9021, when the thickness of the first collimation component 9021 is too small, the processing difficulty of the collimation lens 902 is also increased.

[0102] Still referring to Figure 16As shown, in some embodiments, the collimating lens 902 further includes a second collimating component 9022, which includes a third surface S3 that is curved for collimating the laser light in the second direction.

[0103] The second direction is still used to represent the fast-axis direction. In one implementation scenario, if the laser light in the slow-axis direction is collimated first and then the laser light in the fast-axis direction is collimated, the third surface S3 is located on the side away from the light-emitting chip 901. In another implementation scenario, if the laser light in the fast-axis direction is collimated first and then the laser light in the slow-axis direction is collimated, the third surface S3 is located on the side close to the light-emitting chip 901.

[0104] To clearly show the structure of the second collimating component 9022, Figure 17 a side view of a collimating lens provided by an embodiment of the present application, Figure 18 a top view of a collimating lens provided by an embodiment of the present application, the structure of the second collimating component 9022 can be combined with Figure 19 , Figure 19 and Figure 12 as shown.

[0105] Figure 16 a schematic diagram of collimating laser light in the fast-axis direction based on the second collimating component provided by an embodiment of the present application, as Figure 12 can be seen, the laser light emitted by the light-emitting point can be collimated in the fast-axis direction after passing through the second collimating component 9022, and a light beam with high collimation degree is obtained.

[0106] Figure 16 a schematic diagram of the shape of a light spot after collimating laser light in the fast-axis direction based on the second collimating component provided by an embodiment of the present application, wherein the circular area can be used to represent a receiving surface, and the dashed area can be used to represent a light spot. In one implementation scenario, Figure 20 0.4800 mm shown is used to define the size of the receiving surface, and based on the size of the receiving surface, the size of the current light spot can be determined.

[0107] In some embodiments, the radius of curvature of the third surface S3 ranges from greater than or equal to -1 mm and / or less than or equal to 1 mm.

[0108] In one implementation scenario, the third surface S3 can be provided by a cylindrical lens.

[0109] In one implementation scenario, when the radius of curvature of the third surface S3 is greater than or equal to -1 mm and / or less than or equal to 1 mm, the laser light in the fast-axis direction can be effectively collimated, and the collimation effect is better.

[0110] Based on the range of the radius of curvature of the third surface S3, the radius of curvature of the third surface S3 can be determined according to different distances and parameters such as the thickness of the collimating lens 902. For example, the radius of curvature of the third surface S3 can be set to -0.273 mm.

[0111] In another implementation scenario, based on the range of the radius of curvature of the third surface S3, when the radius of curvature of the third surface S3 is too large or too small, the collimation degree of the laser in the fast-axis direction is reduced, affecting the collimation effect.

[0112] In some embodiments, the thickness of the second collimating component 9022 ranges from greater than or equal to 0.2 mm and / or less than or equal to 0.6 mm.

[0113] In combination with FIGS. 9A and 9B, Figure 2 and Figure 12 In an implementation scenario, the second collimating component 9022 further includes a fourth surface S4 opposite to the third surface S3, and the second surface S2 of the first collimating component 9021 is attached to the fourth surface S4. At this time, the thickness of the second collimating component 9022 is the distance between the center of the third surface S3 and the fourth surface S4, that is, Figure 20 and Figure 21 d2 shown in FIGS. 9A and 9B.

[0114] In an implementation scenario, when the thickness of the second collimating component 9022 is greater than or equal to 0.2 mm and / or less than or equal to 0.6 mm, not only is the second collimating component 9022 not too thick, which is conducive to the miniaturization of the laser light source 90, but also facilitates the processing of the collimating lens 902. Based on the range of the thickness of the second collimating component 9022, the thickness of the second collimating component 9022 can be set according to actual needs. For example, the thickness of the second collimating component 9022 can be set to 0.4 mm.

[0115] In another implementation scenario, based on the range of the thickness of the second collimating component 9022, when the thickness of the second collimating component 9022 is too thick, such as greater than 0.6 mm, the volume of the second collimating component 9022 is increased, which is not conducive to the miniaturization of the laser light source 90 and also increases the processing difficulty of the collimating lens 902.

[0116] In another implementation scenario, based on the range of the thickness of the second collimating component 9022, when the thickness of the second collimating component 9022 is too thin, such as less than 0.6 mm, the processing difficulty of the collimating lens 902 is increased.

[0117] In summary, the collimating lens 902 includes a plurality of first collimating components 9021 corresponding to the light emitting points. The curvature radius of the first surface S1 of the first collimating component 9021 is set so that the first collimating component 9021 can effectively collimate the laser light in the slow axis direction. Since the laser light in the slow axis direction is collimated, the collimation degree is high. For a projection system including a DOE, the light beam with high collimation degree is incident on the DOE, effectively improving the efficiency of the DOE. At the same time, since the collimation degree of the laser light in the slow axis direction is high, as the optical path increases, the laser light corresponding to the multiple light emitting points is still in a collimated state in the slow axis direction, thereby effectively avoiding the overlapping of the light spots corresponding to the laser light emitted by the multiple light emitting points, obtaining separated light spots, and the separated light spots are incident on the DOE, which is beneficial to further improving the diffraction efficiency of the DOE and thus improving the efficiency of the projection system. The collimating lens 902 not only collimates the laser light in the slow axis direction, but also includes a second collimating component 9022 for collimating the laser light in the fast axis direction, which is beneficial to improving the beam quality and effectively avoiding the problem of increasing the size of the light spot as the optical path increases, thereby reducing the design difficulty of the subsequent optical system.

[0118] Figure 1 Structure diagram of a laser light source provided by an embodiment of the present application Figure 21 , referring to Figure 21 , in one or more embodiments of the present application, the laser light source 90 further includes a cover plate 904 located on the light emitting side of the collimating lens 902, the thickness of the cover plate 904 is greater than or equal to 0.5 mm, and / or less than or equal to 1 mm.

[0119] Based on the thickness range of the cover plate 904, the cover plate 904 has good strength while avoiding excessive volume of the cover plate 904, which is beneficial to miniaturization of the laser light source 90. The specific thickness of the cover plate 904 can be set according to actual needs, for example, it can be 0.5 mm.

[0120] In another implementation scenario, the thicker the thickness of the cover plate 904, the better the strength. However, based on the thickness range of the cover plate 904, when the thickness of the cover plate 904 is too thick, the volume of the laser light source 90 will increase, and the cost will also increase.

[0121] In another implementation scenario, based on the thickness range of the cover plate 904, when the thickness of the cover plate 904 is too thin, the strength of the cover plate 904 is poor and is prone to cracking.

[0122] In some embodiments, referring to Figure 21As shown, the laser light source 90 can further include a heat sink 905, and the light emitting chip 901 is fixed on the bottom plate 906 through the heat sink 905. The reflecting device 903 is located on the light exit side of the collimating lens 902, and is used to reflect the collimated laser light emitted by the collimating lens 902 to the opening, and then the laser light is emitted after passing through the cover plate 904, where the opening is the opposite side of the bottom plate 906.

[0123] In some embodiments, the laser light source 90 further includes a lens assembly 907 located on the light exit side of the cover plate 904, and used to shape the laser light emitted by the cover plate 904, or to collimate the laser light emitted by the cover plate 904 in the second direction.

[0124] In an implementation scenario, when the lens assembly 907 is used to shape the laser light emitted by the cover plate 904, the shape of the corresponding light spot of the laser light can be changed, for example, the shape of the light spot of the laser light can be an ellipse before the laser light is incident on the lens assembly 907, and after the laser light is shaped by the lens assembly 907, a rectangular light spot with uniform distribution can be obtained.

[0125] Meanwhile, the lens assembly 907 can also change the propagation direction of the laser light, for example, for a projection system including a light guide pipe, the laser light can be directly incident in the light guide pipe after passing through the lens assembly 907, which is conducive to the miniaturization of the projection system.

[0126] In another implementation scenario, when the lens assembly 907 is used to collimate the laser light in the fast axis direction emitted by the cover plate 904, the lens assembly 907 can include a plurality of lenses, and the lenses correspond to the reflecting devices 903 one by one. Since the collimation of the laser light inside the laser light source needs high precision, for the fast axis direction, the collimating lens 902 can be used to collimate the laser light in the fast axis direction, and the divergence angle of the laser light in the fast axis direction is 0° after collimation. However, due to various factors, there can be a certain deviation, and at this time, the lens assembly 907 can be used to collimate the laser light emitted by the reflecting device 903 in the fast axis direction for the second time, and adjust the laser light in the fast axis direction, so as to obtain a light beam with higher collimation.

[0127] In summary, the laser light source 90 further includes the cover plate 904, the lens assembly 907 and the like, where the cover plate 904 is used to realize air tightness, and by limiting the thickness of the cover plate 904, the cover plate 904 can have good strength while avoiding the cover plate 904 being too large in size, which is conducive to the miniaturization of the laser light source 90.

[0128] The embodiment of the present application provides a display device.

[0129] Figure 22 The structure of the display device provided by the embodiment of the present application is shown in Figure 2 , referenceFigure 21 As shown, generally, the optical system can be divided into a light source part 10, an optical engine part 20, and a lens part 30 according to the functions of the optical system, wherein the light source part 10, the optical engine part 20, and the lens part 30 are also collectively referred to as an optical engine, and the lens part 30 is a projection lens.

[0130] The light source part 10 includes a laser light source 90, a light combining assembly 110, and a first lens assembly 120. The laser light source 90 can emit red, green, and blue laser light. The light combining assembly 110 combines the red, green, and blue laser light. The combined laser light is emitted to the optical engine part 20 through the first lens assembly 120.

[0131] The optical engine part 20 is configured to homogenize and shape the red, green, and blue laser light. The optical engine part 20 includes a homogenizing device 201, a relay lens 202, a prism assembly 203, and an amplitude light modulating device 204. The homogenizing device 201 homogenizes the laser light, and the homogenized laser light is incident on the prism assembly 203 through the relay lens 202. The prism assembly 203 reflects the laser light to the amplitude light modulating device 204, thereby illuminating the amplitude light modulating device 204. The laser light is modulated by the amplitude light modulating device 204, and then the modulated laser light is incident on the lens part 30 through the prism assembly 203, thereby achieving projection.

[0132] The amplitude light modulating device 204 is also referred to as a light valve modulating device, and is a core component of a display device. The amplitude light modulating device 204 can be a transmissive LCD, an LCOS, a DMD chip, or the like. Figure 22 The amplitude light modulating device 204 shown in FIG. 1 is a DMD chip, and can be applied to a DLP projection architecture. The homogenizing device 201 can be a light pipe or a double-sided fly's eye lens, or the like. ​ The illumination scheme shown in FIG. 2 is a double-sided fly's eye lens illumination scheme.

[0133] ​ A structure of a display device provided in an embodiment of the present application ​ The display device includes a laser light source 90, a diffractive optical element 400, a light combining assembly 110, a lens 500, a prism assembly 203, an amplitude light modulating device 204, and a lens part 30.

[0134] The laser light source 90 can emit red, green, and blue laser light. The laser light is shaped and homogenized by the corresponding diffractive optical element 400, and then is incident on the light combining assembly 110. The laser light is incident on the amplitude light modulating device 204 through the light combining assembly 110, the lens 500, and the prism assembly 203. The laser light is modulated by the amplitude light modulating device 204, and then is incident on the lens part 30 through the prism assembly 203, thereby achieving projection.

[0135] It should be noted that, ​ and ​ The structures of the two display devices shown are only exemplary, and do not limit the structure of the display device.

[0136] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

[0137] The above description has been made in conjunction with specific embodiments for the convenience of explanation. However, the above exemplary discussion is not intended to exhaust or limit the embodiments to the specific forms disclosed above. Various modifications and variations can be derived according to the above teachings. The selection and description of the above embodiments are to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different modified embodiments suitable for specific use considerations.

Claims

1. A laser light source, characterized by, The laser light source comprises a plurality of light emitting chips and a plurality of collimating lenses corresponding to the plurality of light emitting chips; The light emitting chip comprises a plurality of light emitting points for emitting laser light along a third direction, a diffusion angle of the laser light in a first direction being smaller than a diffusion angle of the laser light in a second direction, the first direction being perpendicular to the second direction, and the first direction and the second direction being perpendicular to the third direction; The collimating lens is located on a light emitting side of the corresponding light emitting chip, for collimating the laser light in the first direction before a plurality of light spots corresponding to the laser light emitted by the plurality of light emitting points in the light emitting chip overlap.

2. The laser light source according to claim 1, characterized by, A distance between the light emitting chip and the collimating lens ranges from greater than or equal to 0.15 mm and / or less than or equal to 0.4 mm.

3. The laser light source according to claim 1 or 2, characterized by, The collimating lens comprises a plurality of first collimating components corresponding to the light emitting points, comprising a first surface, the first surface being a curved surface for collimating the laser light in the first direction.

4. The laser light source according to claim 3, characterized by A radius of curvature of the first surface ranges from greater than or equal to -1 mm and / or less than or equal to 1 mm.

5. The laser light source according to claim 3, wherein A thickness of the first collimating component ranges from greater than or equal to 0.1 mm and / or less than or equal to 0.3 mm. The thickness of the first collimating component is a distance between a center of the first surface and a second surface, the second surface being a plane opposite to the first surface in the first collimating component.

6. The laser light source according to claim 1 or 2, wherein The collimating lens further comprises a second collimating component, the second collimating component comprising a third surface, the third surface being a curved surface for collimating the laser light in the second direction.

7. The laser light source according to claim 6, characterized by A radius of curvature of the third surface ranges from greater than or equal to -1 mm and / or less than or equal to 1 mm.

8. The laser light source according to claim 6, characterized by, A thickness of the second collimating component ranges from greater than or equal to 0.2 mm and / or less than or equal to 0.6 mm.

9. The laser light source of claim 1, wherein, The laser light source further comprises a cover plate located on a light emitting side of the collimating lens, a thickness of the cover plate being greater than or equal to 0.5 mm and / or less than or equal to 1 mm.

10. The laser light source according to claim 9, characterized by The laser light source further comprises a lens assembly located on a light emitting side of the cover plate for shaping the laser light emitted by the cover plate or collimating the laser light in the second direction emitted by the cover plate.

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