Projection light source and projection equipment

Abstract

A projection light source (10) and a projection apparatus. The projection light source (10) comprises a laser (101), a first light path guiding element (102), a second light path guiding element (103), a first dimming part (104) and a second dimming part (105), wherein the first dimming part (104) and the second dimming part (105) are moving parts; the laser (101) is used for emitting laser of at least one color; the first light path guiding element (102) is used for guiding laser to enter the first light adjusting part (104), and the first light adjusting part (104) is used for increasing a first optical expansion amount for the incident laser and then emitting the laser; the number of the second light path guiding elements (103) and the number of the second dimming parts (105) are both greater than or equal to 1, and each second light path guiding element (103) corresponds to one second dimming part (105); the second light path guiding element (103) is used for receiving laser emitted from one dimming part except the corresponding second dimming part (105) and guiding the received laser to the corresponding second dimming part (105), and the second dimming part (105) is used for increasing a second optical expansion amount for the incident laser and then emitting the laser.

Description

Projection light source and projection equipment

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the China Patent Office on October 28, 2022, with application number 202211338514.9, and invention name “Projection Light Source and Projection Equipment”, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of optoelectronic technology, and in particular to a projection light source and a projection device. Background Art

[0004] With the development of optoelectronic technology, projection equipment has been widely used.

[0005] In related technologies, projection devices use lasers in their light sources to emit multiple colors of laser light, which can then be used to form and project a projection image. The laser light emitted by the laser has high coherence, resulting in the appearance of alternating bright and dark spots in the projected image. This phenomenon is known as speckle, and it can degrade the user's viewing experience of the projected image.

[0006] Summary of the Invention

[0007] In one aspect, the present application provides a projection light source, comprising: a laser, a first light path guiding element, a second light path guiding element, a first light modulating unit and a second light modulating unit, wherein the first light modulating unit and the second light modulating unit are both moving parts;

[0008] The laser is used to emit laser light of at least one color; the first light path guiding element is used to guide the laser light of at least one color to be incident on the first light modulating unit, and the first light modulating unit is used to increase the first optical etendue of the incident laser light before emitting the laser light;

[0009] The number of the second optical path guiding elements and the number of the second dimming units are both greater than or equal to 1, and each second optical path guiding element corresponds to a second dimming unit; the second optical path guiding element is used to: receive laser light emitted from a dimming unit other than the corresponding second dimming unit, and guide the received laser light to the corresponding second dimming unit, and the second dimming unit is used to increase the second optical expansion of the incident laser light and then emit it.

[0010] On the other hand, a projection device is provided, comprising: the above-mentioned projection light source, a light valve, and a lens;

[0011] The projection light source is used to emit laser light toward the light valve, the light valve is used to modulate the received laser light and emit it toward the lens, and the lens is used to project the received laser light to form a projection image. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings introduced below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0013] FIG1 is a schematic structural diagram of a projection light source provided in an embodiment of the present application;

[0014] FIG2 is a schematic structural diagram of another projection light source provided in an embodiment of the present application;

[0015] FIG3 is a schematic structural diagram of another projection light source provided in an embodiment of the present application;

[0016] FIG4 is a schematic structural diagram of a diffusion wheel provided in an embodiment of the present application;

[0017] FIG5 is a schematic structural diagram of another projection light source provided in an embodiment of the present application;

[0018] FIG6 is a schematic structural diagram of another diffusion wheel provided in an embodiment of the present application;

[0019] FIG7 is a schematic structural diagram of a projection light source provided by another embodiment of the present application;

[0020] FIG8 is a schematic structural diagram of another diffusion wheel provided in an embodiment of the present application;

[0021] FIG9 is a schematic structural diagram of another projection light source provided by another embodiment of the present application;

[0022] FIG10 is a schematic structural diagram of another diffusion wheel provided in an embodiment of the present application;

[0023] FIG11 is a schematic structural diagram of yet another projection light source provided by another embodiment of the present application;

[0024] FIG12 is a schematic structural diagram of a diffusion wheel provided in another embodiment of the present application;

[0025] FIG13 is a schematic structural diagram of another projection light source provided by another embodiment of the present application;

[0026] FIG14 is a schematic structural diagram of another diffusion wheel provided in another embodiment of the present application;

[0027] FIG15 is a schematic structural diagram of a projection light source provided by yet another embodiment of the present application;

[0028] FIG16 is a schematic structural diagram of another projection light source provided in yet another embodiment of the present application;

[0029] FIG17 is a schematic structural diagram of another projection light source provided by yet another embodiment of the present application;

[0030] FIG18 is a schematic structural diagram of another projection light source provided by yet another embodiment of the present application;

[0031] FIG19 is a schematic structural diagram of a projection light source provided by another embodiment of the present application;

[0032] FIG20 is a schematic structural diagram of another projection light source provided in yet another embodiment of the present application;

[0033] FIG21 is a schematic structural diagram of a laser provided in an embodiment of the present application;

[0034] FIG22 is a schematic diagram of the structure of another laser provided in an embodiment of the present application;

[0035] FIG23 is a schematic structural diagram of another laser provided in an embodiment of the present application;

[0036] FIG24 is a schematic structural diagram of another laser provided in an embodiment of the present application;

[0037] FIG25 is a schematic diagram of a light spot formed by laser light emitted by a laser provided in an embodiment of the present application;

[0038] FIG26 is a schematic diagram of a partial structure of a projection light source provided in an embodiment of the present application;

[0039] FIG27 is a schematic diagram of a partial structure of another projection light source provided in an embodiment of the present application;

[0040] FIG28 is a schematic diagram of a partial structure of another projection light source provided in an embodiment of the present application;

[0041] FIG29 is a schematic diagram of a partial structure of another projection light source provided in an embodiment of the present application;

[0042] FIG30 is a schematic diagram of a light spot formed by a laser directed toward a light combining component provided in an embodiment of the present application;

[0043] FIG31 is a schematic diagram of a light spot formed by laser light emitted by a light combining component provided in an embodiment of the present application;

[0044] FIG32 is a schematic structural diagram of another projection light source provided in yet another embodiment of the present application;

[0045] FIG33 is a schematic structural diagram of a projection device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0047] With the development of optoelectronic technology, the application of projection equipment is becoming more and more widespread, and the requirements for the display effect of the projected images of projection equipment are becoming increasingly higher. Due to the high coherence of laser light, speckle phenomenon may appear in the projected image, affecting the display effect of the projected image. Therefore, how to better eliminate speckle has become a research focus in the laser projection industry. The following embodiments of this application provide a projection light source and projection equipment that can effectively reduce the speckle phenomenon in the projected image. The laser light emitted by this projection light source can form a projection image with better display effect.

[0048] Figure 1 is a schematic diagram of the structure of a projection light source provided in an embodiment of the present application, Figure 2 is a schematic diagram of the structure of another projection light source provided in an embodiment of the present application, and Figure 3 is a schematic diagram of the structure of yet another projection light source provided in an embodiment of the present application. As shown in Figures 1 to 3, the projection light source 10 may include a laser 101, a first light path guiding element 102, a second light path guiding element 103, a first light modulating unit 104, and a second light modulating unit 105.

[0049] Laser 101 is configured to emit laser light of at least one color. In the embodiments of the present application, laser 101 can be a monochromatic laser or a multicolor laser. A monochromatic laser only emits one color of laser light, while a multicolor laser can emit multiple colors of laser light. A first optical path guiding element 102 is configured to guide the at least one color of laser light emitted by laser 101 to a first light modulating unit 104 for incident light. First light modulating unit 104 is configured to increase the first optical etendue of the incident laser light before emitting the light.

[0050] The number of second light path guiding elements 103 and the number of second light modulating units 105 are both greater than or equal to one, and each second light path guiding element 103 corresponds to one second light modulating unit 105. The number of second light path guiding elements 103 and the number of second light modulating units 105 can be equal, with a one-to-one correspondence between the second light path guiding elements 103 and the second light modulating units 105. In one specific implementation, the number of second light path guiding elements 103 can also be greater than the number of second light modulating units 105, and two or more second light path guiding elements 103 can correspond to the same second light modulating unit 105.

[0051] The second optical path guiding element 103 is used to receive laser light emitted from a dimming section other than the corresponding second dimming section 105, and guide the received laser light to the corresponding second dimming section 105, and the second dimming section 105 is used to increase the second optical expansion of the incident laser light before emitting it. For a second optical path guiding element 103, the dimming section other than the second dimming section 105 corresponding to the second optical path guiding element 103 can be the first dimming section 104, or it can also be another second dimming section 105. In a specific implementation, the first dimming section 104 can also serve as the second dimming section corresponding to a second optical path guiding element 103. In this way, the laser light emitted by the laser 101 in the projection light source 10 can be subjected to multiple increases in optical expansion, and the number of times can be equal to the number of second optical path guiding elements 103 plus one.

[0052] It should be noted that the optical expansion is the integral of the beam source area and the solid angle occupied by the beam. The optical expansion can measure the change in the beam source area and the solid angle when the light beam passes through the optical system. The larger the beam source area or the solid angle, the larger the optical expansion. Increasing the optical expansion of the light beam can be increasing at least one of the source area and the solid angle of the light beam. The beam source area can also be regarded as the area of ​​the light spot formed by the light beam, and the solid angle can be regarded as the divergence angle of the light beam. In the embodiment of the present application, the first dimming unit 104 and the second dimming unit 105 increase the optical expansion of the received laser, which can be used to diffuse the laser to increase the spot area of ​​the laser or increase the divergence angle of the laser.

[0053] Each dimming unit in the projection light source 10 can have the same or different degrees of diffusion for the received laser light. The present embodiment does not limit the amount of etendue added by each dimming unit to the laser light. For example, the first dimming unit 104 adds a first etendue to the received laser light, and the second dimming unit 105 adds a second etendue to the received laser light. The first etendue can be equal to, greater than, or less than the second etendue. The second etendues corresponding to each second dimming unit 105 can be the same or different.

[0054] In a projection light source 10 of an embodiment of the present application, as shown in Figures 1 and 2, the projection light source 10 may include a first dimming unit 104 and a second dimming unit 105. The laser light emitted by the laser 101 is guided by the first optical path guiding element 102 to enter the first dimming unit 104. The laser light emitted by the first dimming unit 103 can be emitted toward a second optical path guiding element 103, and then guided by the second optical path guiding element 103 to enter its corresponding second dimming unit 105 and then emitted. Since the first dimming unit 104 and the second dimming unit 105 are both used to increase the optical expansion of the laser light, the laser light emitted by the laser 101 in the embodiment of the present application can increase the optical expansion twice, which has a strong effect on reducing the coherence of the laser light, and can reduce the speckle effect of the projection image formed based on the laser light.

[0055] As shown in FIG3 , the projection light source 10 may include a dimming section 104 and multiple second dimming sections 105 . FIG3 uses two second dimming sections 105 as an example. The laser light emitted by the first dimming section 103 may be emitted toward a second optical path guiding element 103, where it is guided by the second optical path guiding element 103 to enter its corresponding second dimming section 105 before being emitted. The laser light emitted from the second dimming section 105 may be emitted toward another second optical path guiding element 103, where it is then guided by the second optical path guiding element 103 to enter its corresponding second dimming section 105 before being emitted. In this way, the laser light emitted by the laser 101 can undergo a threefold increase in optical etendue, further reducing the coherence of the laser light.

[0056] In an embodiment of the present application, as shown in Figure 1, the first dimming unit 104, the second light path guiding element 103 and the second dimming unit 105 in the projection light source 10 can be arranged on the same straight line; or as shown in Figures 2 and 3, the first dimming unit 104 and the second dimming unit 105 can be arranged in the same plane, and the second light path guiding element 103 is used to turn the transmission direction of the laser; or, the various dimming units and light path guiding elements can also be arranged in any other arrangement manner. In the embodiment of the present application, there is no limitation on the setting position of each dimming unit and light path guiding element.

[0057] In the embodiment of the present application, both the first dimming unit 104 and the second dimming unit 105 can be moving components. For example, each dimming unit can rotate, translate, or move in other ways, which is not limited in the embodiment of the present application. For a dimming unit, when it moves, the laser can be directed to different positions within the dimming unit at different times, equivalent to the laser being adjusted by different dimming structures at different times. This can reduce the coherence of the laser light in the temporal dimension, effectively reducing the speckle effect of the projected image formed by the laser light.

[0058] In summary, in the projection light source provided in the embodiment of the present application, the laser light emitted by the laser can be guided by the first optical path guiding element to the first dimming part, so that the laser light increases the first optical expansion under the action of the first dimming part. The second optical path guiding component can guide the laser light emitted by other dimming parts (such as the first dimming part or other second dimming parts) to the corresponding second dimming part, so that the laser light increases the second optical expansion under the action of the second dimming part. In this way, the laser light emitted by the laser can increase the optical expansion at least twice, which can largely eliminate the coherence of the laser light, reduce the speckle phenomenon of the projection picture formed based on the laser light, and improve the display effect of the projection picture.

[0059] Moreover, the first dimming unit and the second dimming unit are both moving parts, so that the lasers directed to the same dimming unit at different times can be directed to different positions of the dimming unit, which can weaken the coherence of the laser in the time dimension and has a better effect on eliminating speckles in the projection image formed based on the laser.

[0060] In one specific implementation, any dimming section in the projection light source 10 can be a transmissive diffuser or a reflective diffuser. In a transmissive diffuser, the light incident surface and the light exit surface of the laser are two opposite surfaces in the diffuser. In a reflective diffuser, the light incident surface and the light exit surface of the laser are the same surface in the diffuser, and the surface opposite to the surface is the reflective surface. Figures 1 and 2 take the example of the first dimming section 104 and the second dimming section 105 in the projection light source 10 being both transmissive diffusers. Figure 3 takes the example of the projection light source 10 including a first dimming section 104 and a second dimming section 105, and the first dimming section 104 and the second dimming section 105 being both reflective diffusers. The diffuser diffuses the laser light, that is, expands the divergence angle of the laser light, so that laser light incident on different positions in the diffuser can be mixed after exiting the diffuser, and laser light that was originally close in space can be separated by a larger distance after exiting the diffuser. This can reduce the spatial coherence of the laser, thereby achieving the effect of eliminating speckles. The diffuser can also diffuse the laser and correspondingly enhance the homogenization effect of the laser.

[0061] Each dimming section in the projection light source 10 can rotate around the same rotation axis. On a plane perpendicular to the rotation axis, the orthographic projection of at least part of the area in each dimming section is located outside the orthographic projection of other dimming sections, that is, at least part of the area in different dimming sections does not overlap. The laser directed to each dimming section can be directed to the area of ​​the dimming section that does not overlap with other dimming sections. The rotation axis described in the embodiment of the present application can refer to a physical structure, or it can be a straight line instead of a physical structure. Each dimming section can be located in the same plane, such as when the plane is perpendicular to the rotation axis, and each dimming section rotates around the same point in the rotation axis; or each dimming section can be located in different planes, such as when different dimming sections are perpendicular to the rotation axis and rotate around different points in the rotation axis, or the dimming sections can also be non-perpendicular to the rotation axis. Each dimming section can be roughly plate-shaped, and the dimming section can have two relatively large surfaces and a plurality of smaller side surfaces connecting the two surfaces. The two larger surfaces are the plate surfaces of the dimming section. In the embodiments of the present application, the description that the dimming unit is located in a certain plane means that the plate surface of the dimming unit is located in the plane, and whether the dimming unit is perpendicular to the rotation axis means whether the plate surface of the dimming unit is perpendicular to the rotation axis.

[0062] In an optional implementation, the dimming sections can be arranged around the rotating shaft in a fan-like arrangement, and each dimming section is not perpendicular to the rotating shaft. On a plane perpendicular to the rotating shaft, the orthographic projections of adjacent dimming sections may or may not overlap. In a specific implementation, the dimming section can be flat, or the dimming section can have a certain curvature. The laser can be directed toward the dimming section in a direction parallel to the rotating shaft. Since the dimming section is tilted relative to the rotating shaft, the optical path of the laser in the dimming section can be longer, which can achieve a better diffusion effect on the laser.

[0063] In another optional implementation, the projection light source 10 may include a diffusion wheel, the above-mentioned rotating shaft may be the rotating shaft of the diffusion wheel, and each dimming part may be a different area in the diffusion wheel (also referred to as a diffusion zone). Figure 4 is a structural schematic diagram of a diffusion wheel provided in an embodiment of the present application. As shown in Figure 4, the diffusion wheel is wheel-shaped, and the diffusion wheel may include a wheel L, and a motor M fixed to the wheel L and located at the center of the wheel L. The wheel L can rotate around the rotating axis Z under the drive of the motor M. Each area in the wheel of the diffusion wheel can diffuse the received laser. The areas in the diffusion wheel described in the embodiment of the present application all refer to the areas in the wheel L of the diffusion wheel.

[0064] In one specific implementation, the diffuser wheel L can have multiple diffusing microstructures (such as strip-shaped protrusions or other shaped microstructures). Each position of the diffuser wheel L is distributed with a diffusing microstructure. The diffuser utilizes these diffusing microstructures to diffuse the received laser light. The diffusing microstructures in different regions of the diffuser wheel can be different. Consequently, as the diffuser wheel rotates, the laser light can be directed to different positions on the diffuser wheel. The diffuser wheel can diffuse the laser light differently, resulting in different phases for the laser light emitted after passing through the diffuser wheel. The diffuser wheel diffuses the laser light during rotation, ensuring that laser light directed to the same spatial position at different times passes through different positions on the diffuser wheel, resulting in different phases for the laser light emitted from the same position at different times. Consequently, the spot formed by the laser light emitted from the same position per unit time can be a superposition of multiple different speckle patterns, thereby reducing the speckle effect and achieving a speckle elimination effect.

[0065] In one embodiment, the wheel L may comprise only a diffuser, or may comprise a carrier and a diffuser positioned on the carrier. The diffuser is configured to diffuse the laser light, and the carrier is light-transmissive. In one embodiment, the diffuser microstructures in the diffuser wheel L may be structures in the diffuser. This embodiment of the present application uses an example in which the diffuser wheel comprises a transmissive diffuser; however, the diffuser wheel may also comprise a reflective diffuser.

[0066] The wheel L can be annular or circular. For example, the wheel L is annular, and the different dimming parts in the projection light source 10 can be different sector ring areas in the circumferential direction of the wheel L. For another example, the wheel L is circular, and the different dimming parts can be different sector ring areas in the circumferential direction of the wheel L. As shown in Figure 4, the wheel L of the diffusion wheel is annular, and the first dimming part 104 and the second dimming part 105 are both semi-circular, and the first dimming part 104 and the second dimming part 105 constitute the wheel L of the diffusion wheel. Figure 5 is a structural schematic diagram of another projection light source provided in an embodiment of the present application. The projection light source shown in Figure 5 includes the diffusion wheel shown in Figure 4, and Figure 4 can be a left view or a right view of the diffusion wheel in the projection light source shown in Figure 5. Please combine Figure 4 with Figure 5. The first light path guiding element 102 can guide the laser to the first area Q1 in the first dimming part 104, and the laser emitted by the first dimming part 104 is guided by the second light path guiding element 103 to pass through the second area Q2 in the second dimming part 105. The first region Q1 and the second region Q2 can be located on opposite sides of the rotation axis Z. The rotation axis Z can be located between the first region Q1 and the second region Q2, such as a line connecting the rotation axis Z passing through the center of the first region Q1 and the center of the second region Q2. In one embodiment, the first region Q1 and the second region Q2 can also be located on different sides of the rotation axis Z. For example, the second region Q2 can be located on the left or right side in Figure 4. The only requirement is that the first region Q1 and the second region Q2 are different.

[0067] It should be noted that the relative positional relationship between the diffuser wheel and other components of the projection light source 10 remains unchanged, and the laser beam's transmission path within the projection light source 10 remains unchanged. However, because the diffuser wheel's blades rotate about their axis, different locations within the diffuser wheel are illuminated by the laser beam at different times as the diffuser wheel rotates. When each dimming section represents a different diffusion zone within the diffuser wheel and is located within the same annular region within the diffuser wheel, each dimming section refers to the area within the diffuser wheel that is illuminated by the laser beam guided by the corresponding light path guiding element, rather than a fixed region within the diffuser wheel. For example, at different times, the first dimming section 104 actually represents different regions within a fixed spatial location within the diffuser wheel.

[0068] Figures 4 and 5 take the example of a projection light source 10 in which the laser light passes through a diffusion wheel twice, and the diffusion wheel only includes a first dimming section 104 and a second dimming section 105. In one specific implementation, the diffusion wheel may also include multiple second dimming sections 105, and the laser light may pass through the diffusion wheel more than twice. Figure 6 is a schematic structural diagram of another diffusion wheel provided in an embodiment of the present application, and Figure 7 is a schematic structural diagram of a projection light source provided in another embodiment of the present application. The projection light source shown in Figure 7 includes the diffusion wheel shown in Figure 6, and Figure 6 can be a left or right view of the diffusion wheel in Figure 7. Please refer to Figures 6 and 7. Based on Figures 4 and 5, the projection light source 10 can further include a second light path guiding element 103. The two second light path guiding elements 103 are respectively located on different sides of the diffusion wheel. For ease of distinction, the second light path guiding element 103 that is the same as that in Figure 5 is labeled 103a in Figure 7, and the second light path guiding element 103 that is also included in Figure 5 is labeled 103b. After the second light path guiding element 103a guides the laser light to pass through the corresponding second light modulating section 105 (such as the second region Q2 therein) and then exit, the laser light can be further guided by the second light path guiding element 103b to pass through the corresponding second light modulating section 105 (such as the third region Q3 therein) for further diffusion. This allows the laser light to diffuse three times through the diffusion wheel, further enhancing the speckle reduction effect. It should be noted that FIG6 does not illustrate the regional division of each light modulating section in the diffusion wheel.

[0069] Figures 6 and 7 take the example of a first region Q1 and a second region Q2 being located on opposite sides of the rotation axis Z, with the third region Q3 located between the first region Q1 and the second region Q2 in the y-direction. The y-direction is perpendicular to the arrangement of the first region Q1 and the second region Q2. In one specific implementation, the positions of the first region Q1, the second region Q2, and the third region Q3 may also be arranged in other optional ways, as long as the three regions are different. Figure 8 is a schematic structural diagram of another diffusion wheel provided in an embodiment of the present application, and Figure 9 is a schematic structural diagram of another projection light source provided in another embodiment of the present application. The projection light source shown in Figure 9 includes the diffusion wheel shown in Figure 8, and Figure 8 can be a left or right view of the diffusion wheel in the projection light source shown in Figure 9. In conjunction with Figures 8 and 9, the first region Q1 and the third region Q3 may also be located on opposite sides of the rotation axis Z, with the second region Q2 located between the first region Q1 and the third region Q3 in the y-direction. It should be noted that Figure 8 does not illustrate the regional division of each dimming unit in the diffusion wheel.

[0070] When the projection light source 10 includes two second light path guiding elements 103, the laser finally exits from the side of the diffusion wheel away from the laser 101 (such as the second side) after passing through the diffusion wheel, so that the subsequent optical elements can be arranged on the second side of the diffusion wheel. In one specific implementation, the projection light source 10 may also include another second light path guiding element 103, so that the laser emitted from the third area Q3 is emitted to another second light path guiding element 103, and is again emitted to the fourth area of ​​the diffusion wheel by the second light path guiding element 103. In this way, it can be ensured that the laser finally exits from the side close to the laser 101 (such as the first side) after passing through the diffusion wheel, and the subsequent optical elements are arranged on the first side of the diffusion wheel. There is no limitation on the number of second light path guiding elements 103 in the embodiments of the present application.

[0071] The above content of the embodiment of the present application takes the example that each dimming part occupies the entire size of the wheel L in the radial direction of the diffusion wheel. If the wheel L is annular and the dimming part is fan-shaped, the ring width of the dimming part is equal to the ring width of the wheel L. In a specific implementation, regardless of whether the wheel L is circular or annular, the wheel L can be divided into multiple annular areas along the radial direction. Different dimming parts in the projection light source 10 can be located in the same annular area in the wheel L, or there can be at least two dimming parts in the projection light source 10, respectively located in two annular areas arranged radially in the wheel L. For example, Figure 10 is a structural schematic diagram of another diffusion wheel provided in the embodiment of the present application, and Figure 11 is a structural schematic diagram of another projection light source provided in another embodiment of the present application. The projection light source shown in Figure 11 includes the diffusion wheel shown in Figure 10, and Figure 10 can be a left view or a right view of the diffusion wheel in the projection light source shown in Figure 11. Figures 10 and 11 illustrate a projection light source 10 comprising a first dimming section 104 and a second dimming section 105, with the two dimming sections being two annular regions within a diffusion wheel L. For example, the first dimming section 104 is located on the outer ring of the wheel L, while the second dimming section 105 is located on the inner ring of the wheel L. The first dimming section 104 surrounds the second dimming section 105. In one embodiment, the second dimming section 105 may also surround the first dimming section 104, although this is not a limitation in this embodiment.

[0072] The first light path guiding element 102 can guide the laser to the first area Q1 in the first dimming part 104, and the laser emitted by the first dimming part 104 is guided by the second light path guiding element 103 to the second area Q2 in the second dimming part 105. The positions of the first area Q1 and the second area Q2 are determined by the positions of the first light path guiding element 102 and the second light path guiding element 103. Figures 10 and 11 take the example that the first area Q1 and the second area Q2 are both located on the same side of the rotation axis Z, and the center of the first area Q1 and the center of the second area Q2 are located on the same straight line with the rotation axis Z. In a specific implementation, Figure 12 is a structural schematic diagram of a diffusion wheel provided in another embodiment of the present application, and Figure 13 is a structural schematic diagram of another projection light source provided in another embodiment of the present application. The projection light source shown in Figure 13 includes the diffusion wheel shown in Figure 12, and Figure 12 can be a left view or a right view of the diffusion wheel in the projection light source shown in Figure 13. As shown in Figures 12 and 13, the first area Q1 and the second area Q2 can also be located on opposite sides of the rotation axis Z, respectively. In a specific implementation, the positions of the first area Q1 and the second area Q2 can also be set arbitrarily, and it is only necessary to ensure that the first area Q1 and the second area Q2 are respectively located in the two annular areas in the wheel L. The embodiment of the present application does not limit the positions of the first area Q1 and the second area Q2, that is, the positions of the first light path guiding element 102 and the second light path guiding element 103 are not limited.

[0073] The above content takes the example that all regions in the diffusion wheel are diffusion areas. In a specific implementation, the diffusion area may only occupy a portion of the diffusion wheel, and the area outside the diffusion area in the diffusion wheel may include at least one of a fluorescence conversion area and a color filter area.

[0074] The fluorescence conversion zone can include a fluorescent material of at least one color, configured to emit fluorescence of a corresponding color when stimulated by the received laser light. Alternatively, the received laser light can be converted into fluorescence. The color of the fluorescence can differ from the color of the laser light. For example, if the laser light emitted by laser 101 is blue, the fluorescence can be red or green. The diffusion wheel can include multiple fluorescence conversion zones, each configured to emit fluorescence of a different color. When the diffusion wheel is further provided with a fluorescence conversion zone, laser 101 can be a monochromatic laser. Because fluorescence has a high degree of phase randomness and is essentially incoherent, providing a fluorescence conversion zone to convert laser light into fluorescence to form a projection image can achieve a superior speckle reduction effect.

[0075] The color filter area is used to filter the received light, increasing the color purity of the filtered light, improving the color contrast of the projected image, and enhancing the display quality of the projected image. For example, each color of fluorescence emitted by the fluorescence conversion area can be filtered by the corresponding color filter area. Because the fluorescence wavelength range is large and the purity is low, the fluorescence wavelength can be reduced to a smaller wavelength range after filtering, thereby improving the purity of the fluorescence.

[0076] The following description will take as an example that the projection light source 10 includes only one first dimming unit 104 and one second dimming unit 105 , and the two dimming units are located in the same annular area of ​​the diffusion wheel, and the laser is diffused twice in the diffusion wheel.

[0077] Regarding the fluorescence conversion zone, the fluorescence conversion zone in the diffusion wheel can be located outside the annular zone where each dimming unit is located. In other words, the fluorescence conversion zone and each dimming unit can be located in different annular zones in the diffusion wheel. The number of fluorescence conversion zones can be Figure 14 is a schematic diagram of the structure of another diffusion wheel provided in another embodiment of the present application, and Figure 15 is a schematic diagram of the structure of a projection light source provided in yet another embodiment of the present application. The projection light source shown in Figure 15 includes the diffusion wheel shown in Figure 14. Figure 14 can be a left or right view of the diffusion wheel in the projection light source shown in Figure 15. As shown in Figures 14 and 15, the diffusion wheel also includes two fluorescence conversion zones located in the same annular zone, namely a first fluorescence conversion zone Y1 and a second fluorescence conversion zone Y2. The embodiment of the present application does not limit the number of fluorescence conversion zones. Figures 14 and 15 use the example of the annular zone where the dimming unit is located surrounding the annular zone where the fluorescence conversion zone is located. In one specific implementation, the annular zone where the fluorescence conversion zone is located can also surround the annular zone where the dimming unit is located. Each fluorescence conversion zone can be fan-shaped, and different fluorescence conversion zones can have different colors. For example, the first fluorescence conversion region Y1 and the second fluorescence conversion region Y2 can be used to be excited by laser to generate red laser and green laser, respectively.

[0078] In one specific implementation, referring again to Figure 14 , the annular region within the fluorescence conversion zone may also include a reflective region Y3, which is used to directly reflect received laser light. As the diffuser wheel rotates, the reflective region and the individual fluorescence conversion regions within the annular region alternately receive laser light, emitting light of different colors from the diffuser wheel at different times. For example, if the laser directed toward the diffuser wheel is blue, this ensures that red, green, and blue light are emitted sequentially as the diffuser wheel rotates. The inclusion of the fluorescence conversion region within the diffuser wheel effectively integrates the diffuser wheel with the fluorescence wheel.

[0079] As shown in FIG15 , the projection light source 10 further includes a third light path guiding element 106, which is used to guide the laser light emitted from the second light modulating section 105 to the phosphor conversion region. When the projection light source 10 includes multiple second light modulating sections 105, the third light path guiding element can guide the laser light emitted after passing through the last second light modulating section 105, so that the laser light is emitted to the phosphor conversion region after passing through all second light modulating sections 105.

[0080] In one embodiment, the fluorescence conversion region and the dimming section can be located in the same annular region of the diffusion wheel, such as the first dimming section. In this case, the laser light can be emitted from the first dimming section after multiple diffusions through the diffusion wheel. This ensures that as the diffusion wheel rotates, the laser light can be received by the subsequent light receiving component regardless of whether it is emitted toward the first dimming section or the fluorescence conversion region.

[0081] Regarding the color filter area, the color filter area in the diffusion wheel can be located outside the annular area where each dimming section is located. The setting method of the color filter area can refer to the setting method of the above-mentioned fluorescence conversion area. The laser can first be filtered by the color filter area, and then diffused by the first dimming section and the second dimming section; or the laser can first be diffused by the first dimming section and the second dimming section, and then filtered by the color filter area. For example, the laser 101 can be a multi-color laser. For each color of laser light emitted by the laser 101, there can be a color filter area corresponding to the laser light for filtering the laser light. The laser 101 can emit multiple colors of laser light in sequence according to a set timing. The rotation pattern of the color filter area in the diffusion wheel can match the emission timing of the laser 101 to ensure that when the laser 101 emits each color of laser light, the color filter area that receives the laser light is the color filter area corresponding to the laser light of that color.

[0082] The projection light source may further include a fourth optical path guiding element configured to guide the laser light to the color filter region. If the laser light is first filtered and then diffused, the fourth optical path guiding element may guide the laser light emitted by the laser to the color filter region. The first optical path guiding element may then guide the laser light emitted from the color filter region to the first dimming unit. If the laser light is first diffused and then filtered, the fourth optical path guiding element may guide the laser light emitted from the second dimming unit to the color filter region.

[0083] In one embodiment, the diffusion wheel may include both a fluorescence conversion region and a diffusion region. The fluorescence conversion region and the color filter region may be located in different annular regions, and the fourth light path guiding element may guide the fluorescence emitted by the fluorescence conversion region to the corresponding color filter region.

[0084] In the embodiment of the present application, the structures of the second light path guiding element, the third light path guiding element and the fourth light path guiding element may be the same. The structures of the light path guiding elements are described below with reference to the accompanying drawings.

[0085] In the first optional implementation of the optical path guiding element, please continue to refer to Figures 5, 7, 9, 11, 13 and 15. The second optical path guiding element 103 may include two reflectors. One of the reflectors is used to receive the laser light emitted by the other dimming part and reflect the received laser light to the other reflector. The other dimming part refers to the dimming part other than the second dimming part 105 corresponding to the second optical path guiding element 103. The other reflector is used to reflect the received laser light to the second dimming part 105 corresponding to the second optical path guiding element 103. The reflectors in the second optical path guiding element can all be tilted and have specific tilt directions and angles to achieve the purpose of reflecting the received laser light to the corresponding position. For example, the second optical path guiding element 103 includes a first reflector J1 and a second reflector J2. The first reflector J1 is used to reflect the laser light received from the diffusion wheel (such as its first area Q1) to the second reflector J2, and the second reflector J2 is used to reflect the received laser light to the diffusion wheel (such as its second area Q2). As shown in Figure 15 , the third optical path guiding element 106 may also include two reflectors, namely a third reflector J3 and a fourth reflector J4. The third reflector J3 is used to reflect the laser light emitted by the second dimming unit 105 toward the fourth reflector J4, and the fourth reflector J4 reflects the received laser light toward the fluorescence conversion area. The structure of the fourth optical path guiding element may also be similar to this, and will not be further described in this embodiment of the application.

[0086] In the second optional implementation of the light path guiding element, FIG16 is a schematic structural diagram of another projection light source provided in another embodiment of the present application. As shown in FIG16 , the second light path guiding element 103 includes a light guide prism D. The light guide prism D has a light receiving surface S3 opposite to the diffusion wheel, and two dimming surfaces respectively connected to two opposite sides of the light receiving surface S3, such as the two dimming surfaces are the first dimming surface S1 and the second dimming surface S2. The light receiving surface S3 is used to transmit the laser received from the diffusion wheel (such as its first area Q1) to one of the two dimming surfaces (such as the first dimming surface S1), the first dimming surface S1 is used to reflect the received laser to the other dimming surface (that is, the second dimming surface S2), the second dimming surface S2 is used to reflect the received laser to the light receiving surface S3, and the light receiving surface S3 is also used to transmit the laser received from the second dimming surface M to the diffusion wheel (such as its second area Q2). The irradiation area of ​​the laser light emitted by the diffusion wheel on the light receiving surface S3 is different from the irradiation area of ​​the second dimming surface S2 on the light receiving surface S3.

[0087] In the embodiment of the present application, a light-guiding prism D can be used to replace any light-guiding element including two reflectors. For example, the second light-guiding element 103 in Figures 5, 7, 9, 11, and 13 can all be a light-guiding prism D, and the second light-guiding element 103 and the third light-guiding element 106 in Figure 15 can both be light-guiding prisms D. The embodiment of the present application only takes the replacement of the second light-guiding element in Figure 5 with a light-guiding prism D and uses Figure 16 as an example. For the application of the light-guiding prism D in other forms of projection light sources 10, the embodiment of the present application does not provide additional illustrations.

[0088] In one specific implementation, the projection light source 10 may further include a phase conversion component for adjusting the phase of the received laser light. At least a portion of the laser light emitted by the laser 101 may also undergo phase adjustment via the phase conversion component to further optimize the speckle elimination effect. If the at least a portion of the laser light is a portion of the laser light emitted by the laser 101 (also a portion of the entire laser light), only this portion of the laser light may undergo phase conversion and diffusion, and the laser light other than this portion of the laser light may not pass through the phase conversion component and may only be diffused. The material of the phase conversion component may include a birefringent material. The phase conversion component may have a variety of optional implementations, two of which are described below as examples.

[0089] In the first optional implementation of the phase conversion component, Figure 17 is a structural schematic diagram of another projection light source provided in another embodiment of the present application. As shown in Figure 17, the first light path guiding element 102 may include a phase conversion component W, and Figure 17 is illustrated by taking the first light path guiding element 102 including only the phase conversion component W as an example. The phase conversion component W can be located between the laser 101 and the diffusion wheel, and is independent of the diffusion wheel. The laser directed to the phase conversion component W passes through the phase conversion component W and then is directed to the first dimming part 104 in the diffusion wheel. It should be noted that the projection light source 10 can include a phase conversion component W based on any of the above structures. The embodiment of the present application only uses the projection light source 10 of Figure 5 as an example. The introduction to the positional relationship of each component in the projection device 10 in the embodiment of the present application is all for the positional relationship of the transmission path of the laser, and this positional relationship may be different from the actual positional relationship in space. If a component is located between two components, it means that the time when the laser hits the component is between the time when the laser hits the two components; if a component is located before (or after) another component, it means that the time when the laser passes through the other component is earlier (or later) than the time when the laser hits the component.

[0090] The phase conversion component W can be located only on the transmission path of a portion of the laser light emitted by the laser 101. Only this portion of the laser light emitted by the laser 101 passes through the phase conversion component W and is emitted to the diffusion wheel. For example, if the orthographic projection of the phase conversion component W on the light-emitting surface of the laser 101 only covers a portion of the light-emitting area on the light-emitting surface, only the laser light emitted from this portion of the light-emitting area can be emitted to the phase conversion component W. The phase conversion component W can adjust the phase of the laser light it receives so that the different phases of the laser light are different from those of the laser light that has not passed through the phase conversion component W. In this way, the laser light can have two different phases after the phase conversion component W, which increases the difference in the laser light, thereby reducing the coherence between the laser light and helping to reduce the speckle effect.

[0091] The phase conversion component W can be stationary relative to the laser 101. For example, the phase conversion component W can include a wave plate, such as a half-wave plate or a quarter-wave plate. If the phase conversion component W includes a half-wave plate, the laser light after the phase conversion component W can be polarized light with orthogonal phases, and the phase difference between the laser light is relatively large. In a specific implementation, the phase conversion component W can also move relative to the laser 101, such as translating back and forth in a certain direction or rotating around a certain direction. At this time, all of the laser light emitted by the laser 101 can be directed toward the phase conversion component W, or part of it can still be directed toward the phase conversion component W. When the phase conversion component W rotates, the angle between the laser light incident on the wave plate and the optical axis of the wave plate continues to change, such as it can change between 0 degrees and 360 degrees, thereby converting the received laser light into non-polarized light. Non-polarized light has a phase difference, which can also increase the phase difference between the laser light, thereby reducing the speckle effect.

[0092] In a second optional implementation of the phase conversion component, the phase conversion component can be fixed to the diffusion wheel, and the phase conversion component can cover at least a portion of the area in the diffusion wheel, such as covering the diffusion area in the diffusion wheel, and the phase conversion component can rotate as the diffusion wheel rotates. For this optional implementation, please continue to refer to Figures 5, 7, 9, 11, 13 and 15. The embodiments of the present application are no longer illustrated by additional drawings. The phase conversion component W can be a wave plate, such as a half-wave plate or other wave plate. If the phase conversion component covers a portion of the area in the diffusion wheel, non-polarized light and linearly polarized light are emitted alternately, which can increase the phase difference of the laser in time. If the phase conversion component covers the entire area in the diffusion wheel, the laser can be converted into non-polarized light.

[0093] For example, if the wheel in the diffusion wheel includes a carrier sheet and a diffuser sheet, the phase shift component W can be located on the side of the carrier sheet away from the diffuser sheet and fixed to the carrier sheet. Alternatively, the phase shift component W can be located on the side of the diffuser sheet away from the carrier sheet and fixed to the diffuser sheet. If the wheel in the diffusion wheel only includes the diffuser sheet, the phase shift component W can be directly fixed to the diffuser sheet. In one specific implementation, the phase shift component W can be fixed to the diffusion wheel by attachment or coating.

[0094] In an embodiment of the present application, the projection light source 10 may further include a homogenizing and shaping component. FIG18 is a schematic diagram of the structure of another projection light source provided in another embodiment of the present application, and FIG19 is a schematic diagram of the structure of a projection light source provided in another embodiment of the present application. As shown in FIG18 , based on FIG5 , the projection light source 10 may further include a homogenizing and shaping component 109, which is used to homogenize and shape the received laser light before emitting it. Shaping the laser light means making the light spot formed by the laser light have a set shape, such as a rectangle. Homogenizing and shaping the laser light can be more conducive to the subsequent use of the laser light. For example, the homogenizing and shaping component 109 may be a light guide, or it may be other components that homogenize and shape the laser light. It should be noted that the projection light source 10 may further include a homogenizing and shaping component 109 based on any of the above structures. The embodiment of the present application only uses the projection light source 10 of FIG5 as an example.

[0095] As shown in Figure 18 , the homogenizing and shaping component 109 can be located after the diffuser wheel. After passing through the diffuser wheel multiple times, the laser beam is directed toward the homogenizing and shaping component 109. As shown in Figure 19 , the second optical path guiding element 103 includes two reflectors (reflectors J1 and J2), and the homogenizing and shaping component 109 can be located between these two reflectors. When the projection light source 10 includes multiple second optical path guiding elements, the homogenizing and shaping component 109 can be located between the two reflectors of any second optical path guiding element.

[0096] In an embodiment of the present application, the laser 101 may be a multi-color laser, and the laser 101 may emit lasers of multiple colors. Figure 20 is a schematic diagram of the structure of another projection light source provided by another embodiment of the present application. As shown in Figure 20, based on any of the above-mentioned projection light sources 10 (the projection light source 10 shown in Figure 5), the first light path guiding element 102 may include a light combining component H, which can mix the multiple colors of laser light emitted by the laser 101 and then emit them to the first dimming unit. For example, the light combining component H can be a light combining lens group, including a plurality of light combining lenses. Different light emitting areas in the laser 101 emit laser light of different colors, and each light combining lens can correspond to a light emitting area. Each light combining lens reflects the laser light emitted by the corresponding light emitting area in the same direction (such as the opposite direction of the x direction in Figure 20) to achieve mixing of the various colors of laser light emitted by the laser 101. For example, the light combining lens at the back of the multiple light combining lenses can be a dichroic mirror, which is used to reflect a laser light emitted from the laser 101 and transmit the laser light emitted from the light combining lens in front of it. In a specific implementation, the laser 101 may also be a monochromatic laser, and the light combining component H may be used to reduce the beam of the laser light emitted by the laser 101 .

[0097] In an optional implementation of the laser 101, the laser 101 may be a multi-chip laser diode (MCL) type laser. The MCL type laser may include a plurality of light-emitting chips arranged in an array in the same tube shell, and each light-emitting chip may emit laser light independently. If the laser 101 is used to emit red, green and blue lasers, the light-combining component H may include three light-combining lenses corresponding to the three-color lasers, respectively. The laser 101 may include 28 light-emitting chips arranged in four rows and seven columns, of which two rows are red light-emitting chips, one row in the other two rows is a green light-emitting chip, and one row is a blue light-emitting chip. The arrangement and number of the light-emitting chips in the laser 101 can also be adjusted arbitrarily, and are not limited in the embodiments of the present application.

[0098] In another optional implementation of the laser 101, Figure 21 is a schematic diagram of the structure of a laser provided in an embodiment of the present application, Figure 22 is a schematic diagram of the structure of another laser provided in an embodiment of the present application, Figure 23 is a schematic diagram of the structure of yet another laser provided in an embodiment of the present application, and Figure 24 is a schematic diagram of the structure of yet another laser provided in an embodiment of the present application. Figures 22 and 23 may be front views of the laser shown in Figure 21, and Figure 24 may be a top view of the laser shown in Figure 21. As shown in Figures 21 to 24, the laser 101 may include a base plate 1011 and two light-emitting modules (not shown in the figures). The two light-emitting modules are both located on the base plate 1011, and the two light-emitting modules may be arranged in sequence along a first direction (such as the x direction). Each light-emitting module may include an annular tube wall 1012 and a plurality of light-emitting chips 1013 surrounded by the tube wall 1012. In a specific implementation, each light-emitting module may be in the shape of an elongated strip, and the orthographic projection of each light-emitting module on the base plate 1011 may be roughly rectangular. The length direction of the rectangle can be parallel to the second direction (such as the y direction), and the width direction can be parallel to the first direction. The multiple light-emitting chips 1013 in each light-emitting module can be arranged in at least one row along the first direction. The embodiment of the present application takes the multiple light-emitting chips arranged in only one row as an example; in a specific implementation, the multiple light-emitting chips can also be arranged in multiple rows, such as two rows or three rows, which is not limited in the embodiment of the present application.

[0099] Each light-emitting module may further include a collimating lens assembly 1014, multiple heat sinks 1015, multiple reflective prisms 1016, and a light-transmitting sealing layer 1018. The multiple heat sinks 1015 and the multiple reflective prisms 1016 may each correspond one-to-one to the multiple light-emitting chips 1013 in the light-emitting module. Each light-emitting chip 1013 is located on a corresponding heat sink 1015, which is used to assist in heat dissipation of the corresponding light-emitting chip 1013. The material of the heat sink 1015 may include ceramic. Each reflective prism 1016 is located on the light-emitting side of the corresponding light-emitting chip 1013. The light-transmitting sealing layer 1018 is located on the side of the tube wall 1012 away from the base plate 1011 and is used to seal the opening on the side of the tube wall 1012 away from the base plate 1011, thereby forming a sealed space together with the base plate 1011 and the tube wall 1012. In one embodiment, the laser 101 may not include the light-transmitting sealing layer 1018, but the collimating lens assembly 1014 may be directly fixed to the surface of the tube wall 1012 away from the bottom plate 1011. In this way, the collimating lens assembly 1014, the tube wall 1012 and the bottom plate 1011 together form a sealed space.

[0100] The collimating lens assembly 1014 is located on the side of the light-transmitting sealing layer 1018 away from the base plate 1011. The collimating lens assembly 1014 includes a plurality of collimating lenses (not shown) corresponding one-to-one to the plurality of light-emitting chips 1013. In the embodiment of the present application, the collimating lenses in each collimating lens assembly 1014 can be integrally formed. For example, the collimating lens assembly 1014 is generally plate-shaped, with the side of the collimating lens assembly 1014 close to the base plate 1011 being flat, and the side away from the base plate 1011 having a plurality of convex curved surfaces, each of which is located on a portion of a collimating lens.

[0101] The light-emitting chip 1013 can emit a laser to the corresponding reflecting prism 1016. The reflecting prism 1016 can reflect the laser to the collimating lens corresponding to the light-emitting chip 1013 in the collimating lens group 1014 in a direction away from the base plate 1011 (such as the z direction), and then the laser can be collimated by the collimating lens and emitted.

[0102] In the embodiment of the present application, the light-emitting chips 1013 in different light-emitting modules in the laser 101 can be used to emit lasers of different colors. It should be noted that the light-emitting chips can be divided according to the color of the light-emitting chips. Each type of light-emitting chip can emit a laser of one color, and different types of light-emitting chips are used to emit lasers of different colors. In the embodiment of the present application, the different light-emitting modules in the laser 101 can include different types of light-emitting chips. Each light-emitting module can include only one type of light-emitting chip, or there can also be a light-emitting module that includes multiple types of light-emitting chips.

[0103] For example, the laser 101 may include three light emitting areas, which are respectively used to emit three colors of laser light. For example, the three light emitting areas include a first light emitting area C1, a second light emitting area C2, and a third light emitting area C3. The laser 101 may include a first light emitting module and a second light emitting module. The first light emitting module may be the light emitting module located on the left side of the figure, and the second light emitting module may be the light emitting module located on the right side of the figure. The first light emitting module may include a plurality of first-class light emitting chips 1013a, and the second light emitting module may include a plurality of second-class light emitting chips 1013b and a plurality of third-class light emitting chips 1013c. For example, the first-class light emitting chip 1013a is used to emit red laser light, the second-class light emitting chip 1013b is used to emit blue laser light, and the third-class light emitting chip 1013c is used to emit green laser light.

[0104] In the embodiment of the present application, the first light emitting area C1 of the laser 101 can be the area where the first light emitting module is located, the second light emitting area C2 is the area where the second type of light emitting chip 1013b is located in the area where the second light emitting module is located, and the third light emitting area C3 is the area where the third type of light emitting chip 1013c is located in the area where the second light emitting module is located. In a specific implementation, the laser 101 may also include only one tube wall 1012, and the multiple light emitting chips 1013 in the laser 101 can be arranged into multiple rows and columns in the one tube wall 1012. The arrangement of the multiple light emitting chips 1013 can be the same as the arrangement of the light emitting chips 1013 in Figure 24, and the embodiment of the present application will not be repeated. In this type of laser 101, each light emitting area is the area where each type of light emitting chip is located.

[0105] In the embodiment of the present application, a first light emitting area C1 includes four light emitting chips 1013a arranged along a first direction, a second light emitting area C2 includes two light emitting chips 1013b arranged along the first direction, and a third light emitting area C3 includes three light emitting chips 1013c arranged along the first direction. Each light emitting chip can emit a small beam of laser light to form a sub-spot. As a result, the laser light emitted from the first light emitting area C1 can form four light spots G1 arranged along the first direction, the laser light emitted from the second light emitting area C2 can form two sub-spots G2 arranged along the first direction, and the laser light emitted from the third light emitting area C3 can form three sub-spots G3 arranged along the first direction. Figure 25 is a schematic diagram of a light spot formed by laser light emitted by a laser provided in an embodiment of the present application.

[0106] Figure 26 is a schematic diagram of a partial structure of a projection light source provided in an embodiment of the present application, Figure 27 is a schematic diagram of a partial structure of another projection light source provided in an embodiment of the present application, Figure 28 is a schematic diagram of a partial structure of yet another projection light source provided in an embodiment of the present application, and Figure 29 is a schematic diagram of a partial structure of yet another projection light source provided in an embodiment of the present application. Figure 27 may be a front view of the structure shown in Figure 26, Figure 28 may be a left view of the structure shown in Figure 26, and Figure 29 may be a top view of the structure shown in Figure 26. As shown in Figures 26 to 29, the first light path guiding element 102 in the projection light source 10 may further include: a dimming structure B, the dimming structure B including a first dimming mirror 1071 and a second dimming mirror 1072 arranged sequentially along the second direction.

[0107] The partial area of ​​the second light emitting area C2 located at one end away from the third light emitting area C3 can be a second sub-area (not marked in the figure), and the partial area of ​​Q1 in the first light emitting area located at this end is a first sub-area (not marked in the figure). The first sub-area and the second sub-area are respectively partial areas located at the same end of the first light emitting area C1 and the second light emitting area C2. In a specific implementation, the first sub-area and the second sub-area can be aligned in the first direction. For example, the first sub-area and the second sub-area are aligned in the first direction at one end close to other areas in the light emitting area. The areas of the first sub-area and the second sub-area may be equal or unequal, and the embodiment of the present application is not limited thereto. For example, the first sub-area in the first light emitting area C1 can be the area where the part of the first type of light emitting chip 1013a located at one end of the first light emitting module is located. The second sub-area in the second light emitting area C2 can be the area where the part of the second type of light emitting chip 1013b located at one end of the second light emitting module is located.

[0108] The orthographic projection of the first dimming mirror 1071 on the laser 101 covers the first sub-area in the first light exit area C1 and the second sub-area in the second light exit area C2. The orthographic projection of the second dimming mirror 1072 on the laser 101 is located outside the third light exit area C3 and on the side of the third light exit area C3 away from the second light exit area C2. The laser light emitted from the first sub-area and the second sub-area can both be directed toward the first dimming mirror 1071. The first dimming mirror 1071 is used to reflect the incident laser light along the second direction toward the second dimming mirror 1072, and the second dimming mirror 1072 is used to reflect the incident laser light toward the light combining component H. The laser light emitted from the area outside the first sub-area in the first light exit area C1 can be directly directed toward the light combining component H; the laser light emitted from the area outside the second sub-area in the second light exit area C2 and the laser light emitted from the third light exit area C3 can be directly directed toward the light combining component H. The light combining component H can then mix the received laser light. Figure 30 is a schematic diagram of a light spot formed by a laser directed toward a light-combining component, provided in an embodiment of the present application. Comparing Figures 25 and 30, it can be seen that the dimming structure B can adjust one light spot G1 and one light spot G2 located at the edge to the other end, thereby improving the symmetry of the three light spots. Figure 31 is a schematic diagram of a light spot formed by a laser emitted from a light-combining component, provided in an embodiment of the present application.

[0109] The first dimming mirror 1071 and the second dimming mirror 1072 can both be rectangular, with the length of the rectangle parallel to the first direction. The first dimming mirror 1071 and the second dimming mirror 1072 can both be tilted, with the first dimming mirror 1071 and the second dimming mirror 1072 being parallel to each other. The second dimming mirror 1072 and the laser 101 are located on the same side of the first dimming mirror 1071 to ensure that the first dimming mirror 1071 can reflect the laser light emitted by the laser 101 toward the second dimming mirror 1072. For example, the angle between the first dimming mirror 1071 and the second dimming mirror 1072 and the second direction can be 45 degrees, and the angle between the first dimming mirror 1071 and the second direction can also be 45 degrees.

[0110] The light-adjusting mirror in the embodiments of the present application can be made of metal, or can be formed by coating a transparent lens with a reflective film. In one specific implementation, the light-adjusting mirror can also be a dichroic mirror. It only needs to ensure that the light-adjusting mirror can emit the incident laser light in the desired direction; whether it can transmit laser light of other colors is not considered.

[0111] In a specific implementation, since the laser will diffuse to a certain extent during the transmission process, the projection light source 10 in the embodiment of the present application may also include a focusing mirror to shrink the angle of the laser during the transmission process. Figure 32 is a structural schematic diagram of another projection light source provided by another embodiment of the present application. As shown in Figure 32, the focusing mirror 108 in the projection light source 10 can be located before the diffusion wheel. Figure 32 takes the example that the first light path guiding element 102 in the projection light source 10 on the basis of Figure 17 also includes a focusing mirror T. The focusing mirror T can be located between the phase conversion component W and the first dimming part (such as the first area Q1 in the diffusion wheel). In a specific implementation, the focusing mirror T can also be located between the diffusion wheel and the second light path guiding element 103, such as between the second lens J2 and the diffusion wheel, or located at other positions, which is not limited in the embodiment of the present application.

[0112] In summary, in the projection light source provided in the embodiment of the present application, the laser light emitted by the laser can be guided by the first light path guiding element to the first dimming part, so that the laser light increases the first optical expansion under the action of the first dimming part. The second light path guiding component can guide the laser light emitted by other dimming parts (such as the first dimming part or other second dimming parts) to the corresponding second dimming part, so that the laser light increases the second optical expansion under the action of the second dimming part. In this way, the laser light emitted by the laser can increase the optical expansion at least twice, which can greatly eliminate the coherence of the laser light, reduce the speckle phenomenon of the projection screen formed based on the laser light, and improve the display effect of the projection screen. In addition, the first dimming part and the second dimming part are both moving parts, so that the laser light emitted at different times can be emitted to different positions of the dimming part, which can reduce the coherence of the laser light in the time dimension, and has a better effect on eliminating speckles of the projection screen formed based on the laser light.

[0113] An embodiment of the present application also provides a projection device. The projection device may include a projection light source, a light valve, and a lens. The projection light source may be any of the projection light sources described above, such as any of the projection light sources 10 in Figures 1 to 3, 5, 7, 9, 11, 13, 15 to 20, and 32. Figure 33 is a schematic structural diagram of a projection device provided in an embodiment of the present application. As shown in Figure 33, the projection device may include any of the projection light sources 10 described above (such as the projection light source 10 shown in Figure 32), and may also include a light valve 20 and a lens 30. The projection device 10 may also include an illumination system (not shown in the figure) located between the projection light source 10 and the light valve 20. The laser emitted by the projection light source 10 may be directed toward the light valve 20 through the illumination system. The light valve 20 is used to modulate the received laser light and direct it toward the lens 30. The lens 30 is used to project the received laser light to form a projection image.

[0114] As shown in FIG33 , the illumination system may include a lens assembly 401, a reflective lens 402, and a total internal reflection (TIR) ​​prism 403. The reflective lens 402 can fold the optical path to ensure a compact projection device. In one embodiment, the light valve 20 may be a digital micromirror device (DMD). In another embodiment, the light valve 20 may be a liquid crystal on silicon (LCOS). The light valve 20 may include multiple reflective sheets, each of which may be used to form a pixel in the projection image. The light valve 20 may reflect the laser light toward the lens 30 from the reflective sheet corresponding to the pixel to be displayed in the bright state, thereby modulating the laser light. The lens 30 may include multiple lenses (not shown). The laser light emitted from the light valve 20 may be emitted sequentially through the multiple lenses in the lens 30.

[0115] In summary, in the projection device provided by the embodiments of the present application, the laser light emitted by the projection light source has a large phase difference and a good mixing effect. Therefore, the speckle phenomenon of the projection image formed by the laser light emitted by the projection light source is relatively weak, the color uniformity of the projection image can be relatively high, and the display effect of the projection image is relatively good.

Claims

1. A projection light source, characterized in that: The projection light source includes: a laser, a first light path guiding element, a second light path guiding element, a first light modulating unit and a second light modulating unit, wherein the first light modulating unit and the second light modulating unit are both moving parts; The laser is used to emit laser light of at least one color; the first light path guiding element is used to guide the laser light of at least one color to be incident on the first light modulating unit, and the first light modulating unit is used to increase the first optical etendue of the incident laser light before emitting the laser light; The number of the second optical path guiding elements and the number of the second dimming units are both greater than or equal to 1, and each second optical path guiding element corresponds to a second dimming unit; the second optical path guiding element is used to: receive laser light emitted from a dimming unit other than the corresponding second dimming unit, and guide the received laser light to the corresponding second dimming unit, and the second dimming unit is used to increase the second optical expansion of the incident laser light and then emit it.

2. The projection light source according to claim 1, characterized in that: Any dimming unit in the projection light source is a transmissive diffuser or a reflective diffuser.

3. The projection light source according to claim 1, wherein: Different dimming parts in the projection light source have the same or different diffusion degrees for the laser light.

4. The projection light source according to any one of claims 1 to 3, characterized in that: Each dimming unit in the projection light source is used to rotate around the same rotation axis; on a plane perpendicular to the rotation axis, the orthographic projection of at least a portion of the area in each dimming unit is located outside the orthographic projections of other dimming units.

5. The projection light source according to claim 4, characterized in that: The rotating shaft is the rotating shaft of the diffusion wheel; The different dimming parts in the projection light source are respectively different sector ring areas or sector-shaped areas in the circumferential direction of the diffusion wheel; or, there are at least two dimming parts in the projection light source, which are respectively located in two annular areas arranged radially in the diffusion wheel.

6. The projection light source according to claim 5, characterized in that: The diffusion wheel further includes: a fluorescence conversion area located outside the annular area where each dimming unit is located, the fluorescence conversion area being configured to convert received laser light into fluorescence for emission; the projection light source further includes a third light path guiding element being configured to guide the laser light emitted by the second dimming unit to the fluorescence conversion area; And / or, the diffusion wheel also includes a color filter area, which is used to filter the received laser and then emit it; the color filter area is located outside the annular area where each dimming part is located, and the projection light source also includes a fourth light path guiding element; the fourth light path guiding element is used to guide the laser emitted by the laser to the color filter area, and the first light path guiding element is used to guide the laser emitted from the color filter area to the first dimming part; or, the fourth light path guiding element is used to guide the laser emitted from the second dimming part to the color filter area.

7. The projection light source according to any one of claims 1 to 3, 5 and 6, characterized in that: For any second light path guiding element and the corresponding second dimming unit: The second light path guiding element includes two reflecting mirrors, wherein one reflecting mirror is used to reflect the laser light received from a light modulating portion other than the second light modulating portion toward the other reflecting mirror, and the other reflecting mirror is used to reflect the received laser light toward the second light modulating portion; Alternatively, the second light path guiding element includes a light guide prism having a light receiving surface and two dimming surfaces respectively connected to two opposite sides of the light receiving surface; the light receiving surface is used to transmit the laser light received from a dimming part other than the second dimming part to one of the two dimming surfaces, the one dimming surface is used to reflect the received laser light to the other dimming surface, and the other dimming surface is used to reflect the received laser light to the The light receiving surface is further configured to transmit the laser light received from the other dimming surface to the second dimming unit.

8. The projection light source according to any one of claims 1 to 3, 5, and 6, characterized in that: The projection light source further includes a phase conversion component, and the phase conversion component is used to adjust the phase of the received laser light; The first light path guiding element includes the phase conversion component, the phase conversion component is stationary relative to the laser, and part of the laser light emitted by the laser passes through the phase conversion component and is emitted to the first dimming unit; Alternatively, each dimming unit in the projection light source is a diffusion area in a diffusion wheel, the phase conversion component is fixed to the diffusion wheel, the phase conversion component covers at least a portion of the diffusion wheel, and the phase conversion component rotates as the diffusion wheel rotates.

9. The projection light source according to any one of claims 1 to 3, 5 and 6, characterized in that: The first light path guiding element includes a light combining component; the laser is used to emit laser light of multiple colors, and the light combining component is used to mix the laser light of multiple colors and then emit it; And / or, the projection light source also includes a homogenizing and shaping component; the laser is emitted toward the homogenizing and shaping component after passing through each of the second dimming parts, or any of the second light path guiding elements includes two reflectors, and the homogenizing and shaping component is located between the two reflectors; the homogenizing and shaping component is used to homogenize and shape the received laser and then emit it.

10. A projection device, characterized in that: The projection device comprises: the projection light source according to any one of claims 1 to 9, a light valve and a lens; The projection light source is used to emit laser light toward the light valve, the light valve is used to modulate the received laser light and emit it toward the lens, and the lens is used to project the received laser light to form a projection image.

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