Projection light source and projection device

Abstract

This application discloses a projection light source and projection device, belonging to the field of optoelectronic technology. In the projection light source, a beam combiner group is located on the light-emitting side of the laser. The beam combiner group, a first prism, a second prism, and a light-uniforming component are arranged sequentially along a first direction. Both the first and second prisms are triangular prisms. The principal cross-section of the first prism is parallel to the principal cross-section of the second prism and parallel to the first direction. On the light-incident surface of the first prism, the length of the laser spot formed in the second direction is greater than its length in the third direction. The first, second, and third directions are mutually perpendicular to each other, and the second direction is parallel to the principal cross-section of the first prism. The angle between the light-incident surface of the second prism and the first direction is greater than the angle between the light-emitting surface of the first prism and the first direction. This application solves the problem of poor display effect of projected images formed by lasers emitted from a projection light source. This application is used for emitting light.

Description

Technical Field

[0001] This application relates to the field of optoelectronic technology, and in particular to a projection light source and projection device. Background Technology

[0002] With the development of optoelectronic technology, projection equipment has been widely used, and the requirements for the display effect of the projected image are becoming increasingly higher.

[0003] The projection light source in the projection device is used to emit laser light, which can then be used to form a projected image. Figure 1 This is a structural diagram of a projection light source provided by related technologies. For example... Figure 1 As shown, the projection light source includes a laser 00 and a beam combiner assembly 01. Lasers of various colors emitted from the laser 00 are directed towards different mirrors in the beam combiner assembly 01, where they are mixed and then emitted. The mixed laser light from the beam combiner assembly 01 can then be directed to a subsequent modulation optical path, modulating the laser light based on the image to be projected before emission, thereby achieving the display of the projected image.

[0004] However, the display effect of the projected image formed by the laser emitted by the projection light source in the related technology is poor. Summary of the Invention

[0005] This application provides a projection light source and projection device, which can solve the problem of poor display effect of projected images. The technical solution includes:

[0006] On the one hand, a projection light source is provided, which includes: a laser, a beam combining mirror group, a first prism, a second prism, and a light homogenizing component;

[0007] The beam combining mirror group is located on the light-emitting side of the laser. The beam combining mirror group, the first prism, the second prism, and the light homogenizing component are arranged sequentially along a first direction. The laser is used to emit laser light into the beam combining mirror group. The beam combining mirror group is used to direct the incident laser light along the first direction toward the first prism. The first prism is used to direct the incident laser light toward the second prism. The second prism is used to direct the incident laser light toward the light homogenizing component. The light homogenizing component is used to homogenize the incident laser light before it is emitted.

[0008] Both the first prism and the second prism are triangular prisms. The main cross-section of the first prism is parallel to the main cross-section of the second prism and parallel to the first direction. On the light-incident surface of the first prism, the length of the laser spot formed in the second direction is greater than the length in the third direction. The first direction, the second direction, and the third direction are perpendicular to each other, and the second direction is parallel to the main cross-section of the first prism. The angle between the light-incident surface of the second prism and the first direction is greater than the angle between the light-outcrystal surface of the first prism and the first direction.

[0009] On the other hand, a projection device is provided, the projection device comprising: the above-described projection light source, as well as a light valve and a lens;

[0010] The projection light source is used to emit laser light into the light valve, the light valve is used to modulate the emitted laser light and direct it toward the lens, and the lens is used to project the emitted laser light to form a projected image.

[0011] The beneficial effects of the technical solution provided in this application include at least the following:

[0012] In this application, the laser emitted from the beam combiner group forms a light spot on the incident surface of the first prism with a length in the second direction greater than its length in the third direction. This second direction is perpendicular to the first direction and parallel to the main cross-section of the first prism. The laser passes through the first prism and then the second prism, with the angle between the incident surface of the second prism and the first direction greater than the angle between the emitting surface of the first prism and the first direction. As a result, the length of the light spot formed on the incident surface of the second prism after exiting the first prism in the second direction is less than the length of the light spot on the emitting surface of the first prism in the second direction. After exiting the second prism, the laser beam is effectively reduced in the second direction, resulting in a smaller aspect ratio of the light spot. This facilitates subsequent light collection, improves laser utilization, and further enhances the display effect of the projected image based on the laser. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of the structure of a projection light source provided by related technologies;

[0015] Figure 2 This is a schematic diagram of the structure of a projection light source provided in an embodiment of this application;

[0016] Figure 3 This is a schematic diagram of another projection light source provided in an embodiment of this application;

[0017] Figure 4 This is a schematic diagram of a laser-formed spot provided in an embodiment of this application;

[0018] Figure 5 This is a schematic diagram of another projection light source provided in the embodiments of this application;

[0019] Figure 6 This is a schematic diagram of another projection light source provided in the embodiments of this application;

[0020] Figure 7 This is a schematic diagram of the structure of a projection light source provided in another embodiment of this application;

[0021] Figure 8 This is a schematic diagram of another projection light source provided in another embodiment of this application;

[0022] Figure 9 This is a schematic diagram of another projection light source provided in another embodiment of this application;

[0023] Figure 10 This is a schematic diagram of the structure of a laser provided in an embodiment of this application;

[0024] Figure 11 This is a schematic diagram of another laser structure provided in an embodiment of this application;

[0025] Figure 12 This is a schematic diagram of the structure of a projection device provided in an embodiment of this application. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0027] With the development of optoelectronic technology, projection equipment is being used more and more widely, and the requirements for the display effect of the projected image are also getting higher and higher, as is the demand for miniaturization of projection equipment. The projection light source plays a crucial role in both the display effect of the projected image and the miniaturization of the projection equipment.

[0028] The projection light source may include a laser, which comprises multiple rows and columns of light-emitting chips. A beam combiner mixes the lasers emitted from each row of chips and directs them towards subsequent optical components. Because the lasers emitted from each row of chips are mixed and emitted after passing through the beam combiner, the overall laser beam has a long and flat cross-section, resulting in a large deviation in the length and width of the formed spot. This leads to significant light loss during subsequent laser transmission, which is detrimental to the formation of the projected image. Furthermore, the light-emitting chips used for different colors of laser light may be located in the same row, resulting in poor overlap of the different color spots after the beam combiner. Different colors of laser light undergo a certain degree of dispersion during transmission through the lens, leading to poor uniformity in the mixing of different colors, which also affects the display effect of the projected image.

[0029] This application provides a projection light source and a projection device, wherein the laser emitted by the projection light source is more suitable for forming a projection image with better display effect.

[0030] Figure 2 This is a schematic diagram of the structure of a projection light source provided in an embodiment of this application. Figure 3 This is a schematic diagram of another projection light source provided in an embodiment of this application. Figure 2 It can be Figure 3 The top view of the laser shown is shown. Figure 3 It can be Figure 2 The image shows a front view of the laser. Figure 2 and Figure 3 As shown, the projection light source 10 may include: a laser 101, a beam combining mirror group 102, a first prism 103, a second prism 104, and a light homogenizing component 106.

[0031] The beam combiner assembly 102 can be located on the light-emitting side of the laser 101. The laser emitted by the laser 101 can pass sequentially through the beam combiner assembly 102, the first prism 103, the second prism 104, and the homogenizing component 106 before being emitted. Specifically, the beam combiner assembly 102, the first prism 103, and the second prism 104 can be arranged sequentially along a first direction (e.g., the x-direction). The laser 101 can emit laser light into the beam combiner assembly 102. The beam combiner assembly 102 can direct the laser light emitted by the laser 101 along the first direction toward the first prism 103. The first prism 103 is used to direct the incoming laser light toward the second prism 104. The second prism 104 is used to direct the incoming laser light toward the homogenizing component 106. The homogenizing component 106 is used to homogenize the incoming laser light before it is emitted.

[0032] Optionally, on the reference plane, the orthographic projection of the first prism 103 can cover the orthographic projection of the beam combining mirror group 102, and this reference plane is perpendicular to the first direction. It should be noted that this reference plane is only an imaginary plane used to describe the positional and size relationships between the various devices, and may not be an actual surface existing in the projection light source. This ensures that all laser light emitted from the beam combining mirror group 102 can enter the first prism 103.

[0033] In this embodiment, both the first prism 103 and the second prism 104 can be triangular prisms. A triangular prism may include three side faces and two base faces. The three side faces form a triangle, located between and connecting the two base faces. The principal cross-section of the prism is a plane perpendicular to the side faces, and the principal cross-section of the prism is triangular. The two base faces can be parallel, such as having the same shape as the principal cross-section of the prism. Optionally, the two base faces may not be parallel, or their shape may differ from the principal cross-section of the prism; this embodiment does not impose such limitations. Figure 2 The triangle representing the first prism 103 and the second prism 104 is the shape of the main cross section of the first prism 103 and the second prism 104.

[0034] The sides of a prism are used for incident and emitted light. In this embodiment, the surface of the prism used for incident light is called the incident surface, and the surface used for emitted light is called the emitted surface. The angle formed by the incident surface and the emitted surface can be called the apex angle of the prism. In this embodiment, the incident surface and emitted surface of the first prism 103 are arranged along a first direction, and the incident surface and emitted surface of the second prism 104 are also arranged along the first direction.

[0035] Please continue to refer to this. Figure 2 and Figure 3 In this embodiment, the principal cross-sections of the first prism 103 and the second prism 104 can both be parallel to the first direction, and the principal cross-sections of the first prism 103 and the second prism 104 are also parallel, or the principal cross-sections of the first prism 103 and the second prism 104 are located in the same plane. The light-emitting surface of the first prism 103 is opposite to the light-incident surface of the second prism 103. The angle between the light-incident surface of the second prism 104 and the first direction can be greater than the angle between the light-emitting surface of the first prism 103 and the first direction. The included angle refers to an angle greater than 0 degrees and less than or equal to 90 degrees. That is, the light-incident surface of the second prism 104 is closer to the plane perpendicular to the first direction than the light-emitting surface of the first prism 103, and the light-emitting surface of the first prism 103 is closer to the first direction than the light-incident surface of the second prism 104.

[0036] For example, Figure 2Taking the example where both the first prism 103 and the second prism 104 are right-angled triangular prisms, the side surface of a right-angled triangular prism includes two right-angled faces and one inclined plane. The right-angled faces are the side surfaces containing the right-angled sides of the principal section of the right-angled triangular prism, and the inclined plane is the side surface containing the hypotenuse of the principal section of the right-angled triangular prism. Furthermore... Figure 2 Taking the two right-angled faces of the first prism 103 as parallel to the first direction (i.e., the x-direction) and the second direction (i.e., the y-direction) respectively, and the two right-angled faces of the second prism 104 as also parallel to the first and second directions respectively, with the second direction perpendicular to the first direction, the angle between the light-emitting surface of the first prism 103 and the first direction is... Figure 2 In the first direction, the angle α is the angle between the incident surface of the second prism 104 and the first direction. Figure 2 In the first prism 103, the apex angle β is greater than α. Correspondingly, the apex angle θ of the second prism 104 can be smaller than the apex angle γ of the first prism 103. It should be noted that the first prism 103 and the second prism 104 may not be right-angled triangular prisms. The specific configuration of the first prism 103 and the second prism 104 will be described in detail later, and will not be repeated here in the embodiments of this application.

[0037] like Figure 2 As shown, the first prism 103 deflects the incoming laser beam in a certain direction, causing it to exit from its exit surface and then enter the incident surface of the second prism 104. The thickness of the laser beam entering the second prism 104 depends on the size of the spot on the incident surface of the second prism 104. This spot is equivalent to a cross-section obtained by using the incident surface of the second prism 104 to cut the laser beam between the first prism 103 and the second prism 104 (i.e., the laser beam emitted from the first prism 103). Similarly, the spot on the exit surface of the first prism 103 is also equivalent to a cross-section obtained by using the exit surface of the first prism 103 to cut the laser beam between the first prism 103 and the second prism 104. The transmission direction of the laser beam is inclined relative to the first direction; the closer the cross-section is to the first direction, the larger the cross-section. The angle between the incident surface of the second prism 104 and the first direction is greater than the angle between the emitting surface of the first prism 103 and the first direction. Therefore, the emitting surface of the first prism 103 is closer to the first direction than the incident surface of the second prism 104. Consequently, the light spot on the emitting surface of the first prism 103 is larger than the light spot on the incident surface of the second prism 104, meaning the light spot on the incident surface of the second prism 104 is smaller than the light spot on the emitting surface of the first prism 103. This ensures that the laser beam entering the second prism 104 is thinner, and correspondingly, the laser beam emitted from the second prism 104 is also thinner. Therefore, the first prism 103 and the second prism 104 can achieve a beam-constricting effect on the laser beam.

[0038] In this embodiment, the length of the laser spot formed on the incident surface of the first prism 103 in the second direction can be greater than its length in the third direction. This third direction is... Figure 2 The direction perpendicular to the paper, that is Figure 3 In the z-direction. Since the relationship between the light-emitting surface of the first prism 103 and the light-incident surface of the second prism 104 is a relationship satisfied within the planes containing the first and second directions, the beam-constricting effect of the first prism 103 and the second prism 104 on the laser is a beam-constriction effect only in the second direction. Thus, after passing through the first prism 103 and the second prism 104, the width of the laser beam in the second direction can be compressed, and the widths of the laser beam in the first and second directions can be closer. That is, the length of the laser spot formed by the laser emitted from the second prism 104 in the second direction is closer to its length in the third direction, and the aspect ratio of the spot is smaller, closer to 1.

[0039] In this embodiment, the laser emitted by laser 101, after being combined by beam combiner group 102, can obtain a generally elongated laser beam. The orthogonal projection of this laser beam onto the reference plane can include multiple light spots arranged along a second direction (such as the y-direction). These multiple light spots can be regarded as a single light spot or a group of light spots, with a relatively large aspect ratio (i.e., the ratio of length to width) and the length direction of the light spot being the second direction. For example, if the aspect ratio of the light spot is approximately 3:1, the size of the light spot can be 18 mm * 6 mm. The aspect ratio of the light spot can also be 3.1:1.1 or other values, and the size of the light spot can also be 19 mm * 7 mm or other sizes; this embodiment does not limit the size.

[0040] For example, Figure 4 This is a schematic diagram of a laser-formed light spot provided in an embodiment of this application. For example... Figure 4 The multiple light spots to the left of the middle arrow can be light spots formed by the laser on the incident surface of the first prism 103. Figure 4 Taking the example where the multiple light spots are all independent and do not overlap. Optionally, adjacent light spots among the multiple light spots may at least partially overlap; this embodiment of the application is not limited to this. After passing through the first prism 103 and the second prism 104, the laser can still continue to propagate along the first direction. Furthermore, the length of the laser spot formed in the second direction can be compressed, for example, by obtaining... Figure 4 The light spot to the right of the middle arrow. (Example) Figure 4 It can be seen that the length and width of the light spot are relatively small, closer to 1.

[0041] It should be noted that the higher the matching degree between the laser beam incident on the homogenizing component and the homogenizing component in the projection light source, the better the light collection effect of the laser, the higher the utilization rate, and the better the display effect of the projected image formed based on the laser. For example, the homogenizing component 106 is a compound eye lens. According to the projection requirements, the homogenizing component 106 must meet certain optical expansion requirements. Based on these optical expansion requirements, the homogenizing component 106 must meet certain structural requirements, such as an aspect ratio within a certain range. Furthermore, the light spot formed on the homogenizing component 106 by the laser beam incident on the homogenizing component 106 must meet certain conditions, such as a small aspect ratio, ideally close to 1. In this embodiment, the cooperation of the first prism 103 and the second prism 104 can ensure that even if the light spot formed by the laser beam emitted from the beam combining lens group 102 has a large aspect ratio, the light spot formed by the laser beam incident on the homogenizing component 106 can still have a small aspect ratio, meeting the projection requirements and thus ensuring a better display effect of the projected image formed based on the laser.

[0042] In summary, in the projection light source provided in this application embodiment, the laser emitted by the beam combiner group forms a light spot on the incident surface of the first prism with a length greater than its length in the third direction. This second direction is perpendicular to the first direction and parallel to the main cross-section of the first prism. The laser passes through the first prism and then the second prism, and the angle between the incident surface of the second prism and the first direction is greater than the angle between the emitting surface of the first prism and the first direction. Therefore, the length of the light spot formed on the incident surface of the second prism by the laser emitted from the first prism in the second direction is less than the length of the light spot on the emitting surface of the first prism in the second direction. After being emitted through the second prism, the laser beam is compressed in the second direction, resulting in a smaller aspect ratio of the light spot. This facilitates subsequent light collection, improves laser utilization, and further enhances the display effect of the projected image based on the laser.

[0043] The conditions that the first prism 103 and the second prism 104 in the projection light source 10 must meet are described below.

[0044] Optionally, the first prism 103 satisfies the following condition: the incident angle of the laser light incident on the light-emitting surface of the first prism 103 is less than the total internal reflection angle of the first prism 103, and the difference between the two angles is within 5 degrees. The second prism 104 satisfies the following condition: the exit angle of the laser light incident on the light-emitting surface of the second prism 104 is less than the total internal reflection angle of the second prism 104, and the difference between the two angles is within 5 degrees. This total internal reflection angle is also the critical angle for total internal reflection of the laser. For example, the total internal reflection angle of the first prism 103 is 41 degrees, and the total internal reflection angle of the second prism 104 is 35 degrees. The total internal reflection angles of the first prism 103 and the second prism 104 can also be changed to some extent based on different prism materials, which is not limited in this embodiment. For example, the incident angle of a laser beam incident on the light-emitting surface of the first prism 103 can range from 36 degrees to 41 degrees. The exit angle of a laser beam incident on the light-emitting surface of the second prism 104 can range from 30 degrees to 36 degrees.

[0045] It should be noted that the closer the incident angle of the laser on the light-emitting surface of the first prism 103 is to the total internal reflection angle, the closer the laser propagates along that light-emitting surface after exiting the first prism 103. Furthermore, by using the light-emitting surface of the second prism 104 as a cutting plane to cut the laser, the size of this cutting plane can be smaller, resulting in a smaller laser spot size on the light-emitting surface of the second prism 104. Thus, the laser emitted from the second prism 104 is thinner, and the length of the laser spot formed in the second direction is shorter, making the beam-constricting effect of the first prism 103 and the second prism 104 on the laser more significant.

[0046] Optionally, both the first prism 103 and the second prism 104 in this embodiment can be right-angled triangular prisms. The two right-angled faces of the first prism 103 can be parallel to the first direction and the second direction, respectively, and the two right-angled faces of the second prism 104 are also parallel to the first direction and the second direction, respectively. The incident surface of the first prism 103 is one of its right-angled faces, and the emitting surface is its inclined surface. The incident surface of the second prism 104 is a right-angled face, and the emitting surface is an inclined surface, or the incident surface of the second prism 104 is an inclined surface, and the emitting surface is a right-angled face. Thus, the apex angle of the first prism 103 is the angle γ between the emitting surface of the first prism 103 and the second direction, and the angle γ is equal to the incident angle of the laser on the emitting surface of the first prism 103. The angle γ is less than the total internal reflection angle of the first prism 103, and differs from the total internal reflection angle by less than 5 degrees. For example, the range of the angle γ is 36 degrees to 42 degrees. For example, the angle γ is 41.2 degrees. The apex angle of the second prism 104 is the angle θ between the incident surface of the second prism 104 and the second direction. Angle θ is equal to the exit angle of the laser beam on the incident surface of the second prism 104. Angle θ is less than the total internal reflection angle of the second prism 104 and within 5 degrees of that angle. For example, the range of angle θ is 30 degrees to 36 degrees. For example, angle θ is 32.8 degrees.

[0047] In the first configuration, the light-emitting surface of the first prism 103 and the light-incident surface of the second prism 104 are both inclined surfaces of a right-angle triangular prism.

[0048] For example, such as Figure 2 As shown, the right-angled faces parallel to the first direction in the first prism 103 and the second prism 104 are right-angled faces on different sides of the second direction. The right-angled face parallel to the first direction in the first prism 103 is... Figure 2 The right-angled face on the lower middle side, and the right-angled face parallel to the first direction in the second prism 104 are... Figure 2 The right-angled face on the upper middle side. Alternatively, the right-angled face parallel to the first direction in the first prism 103 can also be... Figure 2 The right-angled face on the upper middle side, and the right-angled face parallel to the first direction in the second prism 104 are... Figure 2 The right-angled surface on the lower middle side is not illustrated in this embodiment.

[0049] For example, Figure 5 This is a schematic diagram of another projection light source provided in an embodiment of this application. For example... Figure 5 As shown, the right-angled faces parallel to the first direction in the first prism 103 and the second prism 104 are respectively right-angled faces on the same side of the second direction. The right-angled faces parallel to the first direction in the first prism 103 and the right-angled faces parallel to the first direction in the second prism 104 are all... Figure 5 The lower right-angled surface. Optionally, both the right-angled surface parallel to the first direction in the first prism 103 and the right-angled surface parallel to the first direction in the second prism 104 can be... Figure 5 The right-angled surface on the upper middle side is not illustrated in this embodiment.

[0050] In the second configuration, the light-emitting surface of the first prism 103 is the inclined surface of a right-angled triangular prism, and the light-incident surface of the second prism 104 is the right-angled surface of a right-angled triangular prism. Furthermore, the light-incident surface of the second prism 104 is perpendicular to the first direction, i.e., parallel to the second direction. The light-emitting surface of the second prism 104 is the inclined surface of a right-angled triangular prism.

[0051] For example, Figure 6 This is a schematic diagram of another projection light source provided in an embodiment of this application. For example... Figure 6 As shown, the right-angled faces parallel to the first direction in the first prism 103 and the second prism 104 are right-angled faces on different sides of the second direction. The right-angled face parallel to the first direction in the first prism 103 is... Figure 6 The right-angled face on the upper middle side, and the right-angled face parallel to the first direction in the second prism 104 are... Figure 6 The lower right-angled surface. Alternatively, the right-angled surface in the first prism 103 parallel to the first direction can also be... Figure 6The right-angled face on the lower middle side, and the right-angled face parallel to the first direction in the second prism 104 are... Figure 6 The right-angled surface on the upper middle side is not illustrated in this embodiment.

[0052] For example, Figure 7 This is a schematic diagram of the structure of a projection light source provided in another embodiment of this application. For example... Figure 7 As shown, the right-angled surfaces parallel to the first direction in the first prism 103 and the second prism 104 are also right-angled surfaces on the same side of the second direction. Both the right-angled surface parallel to the first direction in the first prism 103 and the right-angled surface parallel to the first direction in the second prism 104 are... Figure 7 The lower right-angled surface. Optionally, both the right-angled surface parallel to the first direction in the first prism 103 and the right-angled surface parallel to the first direction in the second prism 104 can be... Figure 7 The right-angled surface on the upper middle side is not illustrated in this embodiment.

[0053] Optionally, the first prism 103 and the second prism 104 may not both be right-angled triangular prisms. For example, one of the two prisms may be a right-angled triangular prism, and the principal section of the other prism may be an acute-angled or obtuse-angled triangle. For ease of description, the prism with an acute-angled triangular principal section will be referred to as an acute-angled triangular prism, and the prism with an obtuse-angled triangular principal section will be referred to as an obtuse-angled triangular prism. Figure 8 This is a schematic diagram of another projection light source provided in another embodiment of this application. For example... Figure 8 As shown, it can be Figure 2 The first prism 103 is changed from a right-angle prism to an acute-angle prism. Alternatively, the first prism 103 can be changed from a right-angle prism to an obtuse-angle prism, or the second prism 104 can be changed from a right-angle prism to an acute-angle prism or an obtuse-angle prism. These methods will not be illustrated in this embodiment.

[0054] For example, the principal sections of the two prisms are both acute triangles, or both are obtuse triangles, or one prism has an acute triangle principal section and the other has an obtuse triangle principal section. Figure 9 This is a schematic diagram of another projection light source provided in another embodiment of this application. For example... Figure 9 As shown, it can be Figure 2 The first prism 103 is changed from a right-angle prism to an acute-angle prism, and the second prism 104 is changed from a right-angle prism to an obtuse-angle prism. Optionally, the first prism 103 can also be changed from a right-angle prism to an obtuse-angle prism, and the second prism 104 can be changed from a right-angle prism to an acute-angle prism; or both the first prism 103 and the second prism 104 can be changed to acute-angle prisms or obtuse-angle prisms. These methods will not be illustrated in the embodiments of this application.

[0055] Optionally, the shortest distance between the light-emitting surface of the first prism 103 and the light-incident surface of the second prism 104 can be less than 20 mm. This shortest distance can also be less than 10 mm. The light-emitting surface of the first prism 103 and the light-incident surface of the second prism 104 can also be in contact, meaning the shortest distance can be zero. This shortest distance can be the minimum length of the space between the light-emitting surface of the first prism 103 and the light-incident surface of the second prism 104 in the first direction. For example, this shortest distance can be the distance between the corner of the first prism 103 closest to the second prism 104 and the light-incident surface of the second prism 104 in the first direction. In this way, the first prism 103 and the second prism 104 are closer together, reducing the transmission distance of the laser between the two prisms, thereby reducing the size of the projection light source. Furthermore, it also facilitates better uniformity in the mixing of various colors of laser light.

[0056] It should be noted that laser light may undergo dispersion when passing through optical devices (such as prisms and lenses), resulting in the dispersed emission of different colors of laser light, which is detrimental to the uniformity of light mixing among various colors. In this embodiment, the Abbe value of the first prism 103 can be greater than the Abbe value of the second prism 104. The Abbe value is also known as the dispersion coefficient; the larger the Abbe value of the optical device, the smaller the dispersion. The dispersion of each glass in the two prisms can be compensated by the other prism, thereby reducing the overall color difference between the two prisms. After the laser light passes through the first prism 103 and the second prism 104 that satisfy the Abbe value relationship, it can play a role in eliminating color difference, ensuring that the transmission paths of various colors of laser light remain the same, thereby improving the uniformity of light mixing, reducing speckle in the projected image, and improving the display effect of the projected image formed by the laser light.

[0057] For example, the Abbe value of the first prism 103 can be greater than 50, and the Abbe value of the second prism 104 can be less than 50. The material of the first prism 103 can be crown glass, which is also known as K-series glass. The material of the second prism can be flint glass, which is also known as F-series glass. For example, the first prism 103 can be made of crown glass material of type H-QK3L, and the second prism 104 can be made of flint glass material of type ZF7.

[0058] The laser 101 in the projection light source 10 is described below with reference to the accompanying drawings.

[0059] The laser 101 in this embodiment can be a multicolor laser. A multicolor laser is a laser that can emit laser light of multiple colors. Figure 10 This is a schematic diagram of the structure of a laser provided in an embodiment of this application. Figure 11 This is a schematic diagram of another laser provided in an embodiment of this application. Figure 10 It can be Figure 11 The top view of the laser shown is shown. Figure 11 It can be Figure 10 The diagram shows a cross-section a-a' of the laser. Please refer to... Figure 10 and Figure 11 The laser 101 may include a plurality of light-emitting chips 1013. These multiple light-emitting chips 1013 can be arranged in multiple rows. In this embodiment, the multiple light-emitting chips 1013 are arranged in two rows, with the two rows arranged along a first direction, and each row containing 7 light-emitting chips 1013. Optionally, the multiple light-emitting chips 1013 can also be arranged in three or more rows, and the number of light-emitting chips 1013 in each row can be 6, 5, or other numbers. The number of light-emitting chips 1013 in different rows can also be different, and this embodiment does not impose any limitations.

[0060] In this embodiment, the laser 101 contains multiple different light-emitting chips 1013 that can emit lasers of different colors. It should be noted that the light-emitting chips can be categorized according to their emission color; each type of light-emitting chip can emit one color of laser, and different types of light-emitting chips are used to emit different colors of laser. In this embodiment, different rows of light-emitting chips in the laser 101 may include different types of light-emitting chips.

[0061] For example, a row of light-emitting chips (such as...) in laser 101 Figure 10 The row of light-emitting chips on the left side may include multiple first-type light-emitting chips 1013a, and the other row may include multiple second-type light-emitting chips 1013b and multiple third-type light-emitting chips 1013c. The wavelengths of the lasers emitted by the first-type light-emitting chips 1013a, second-type light-emitting chips 1013b, and third-type light-emitting chips 1013c decrease sequentially. For example, the first-type light-emitting chips 1013a are used to emit red lasers, the second-type light-emitting chips 1013b are used to emit green lasers, and the third-type light-emitting chips 1013c are used to emit blue lasers. The lasers emitted by these three types of light-emitting chips can also be other colors, such as the second-type light-emitting chip 1013b emitting yellow lasers; this embodiment of the application does not limit this.

[0062] It should be noted that, in this embodiment, the number of first-type light-emitting chips 1013a is 7, the number of second-type light-emitting chips 1013b is 4, and the number of third-type light-emitting chips 1013c is 3, with the second-type light-emitting chips 1013b located on both sides of the third-type light-emitting chips 1013c, as illustrated. The number of these three types of light-emitting chips can also be adjusted according to requirements. For example, the number of first-type light-emitting chips 1013a can be 6 or other values, the number of second-type light-emitting chips 1013b can be 3 or other values, and the number of third-type light-emitting chips 1013c can be 2 or other values. This embodiment does not impose any limitations. Optionally, the positions of the second-type light-emitting chips 1013b and the third-type light-emitting chips 1013c can also be adjusted. For example, the second-type light-emitting chips 1013b can all be located on the same side of the third-type light-emitting chips 1013c, or the two types of light-emitting chips can be arranged alternately. This embodiment does not impose any limitations.

[0063] Please continue to refer to this. Figure 10 and Figure 11 The laser 101 may further include a base plate 1011, an annular tube wall 1012, a collimating lens group 1014, multiple heat sinks 1015, multiple reflecting prisms 1016, and a light-transmitting sealing layer 1018. The tube wall 1012, the light-emitting chip 1013, the heat sink 1015, and the reflecting prisms 1016 are all located on the base plate 1011, and the tube wall 1012 surrounds the light-emitting chip 1013, the heat sink 1015, and the reflecting prisms 1016. Optionally, the tube wall 1012 may be square annular. The orthographic projection of the tube wall 1012 onto the base plate 1011 may be rectangular or approximately rectangular. For example, the orthographic projection may be a rounded rectangle or a chamfered rectangle. A rounded rectangle is a shape obtained by changing the corners of a rectangle to rounded corners, and a chamfered rectangle is a shape obtained by changing the corners of a rectangle to chamfered corners.

[0064] Each of the multiple heat sinks 1015 and the multiple reflecting prisms 1016 can correspond one-to-one with a multiple light-emitting chip 1013. Each light-emitting chip 1013 is located on a corresponding heat sink 1015, which assists in heat dissipation for the corresponding light-emitting chip 1013. The material of the heat sink 1015 may include ceramic. Each reflecting prism 1016 is located on the light-emitting side of the corresponding light-emitting chip 1013 and is used to reflect the laser emitted by that light-emitting chip 1013.

[0065] 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, so as to form a sealed space together with the base plate 1011 and the tube wall 1012. Optionally, the laser 101 may not include the light-transmitting sealing layer 1018, and the collimating lens assembly 1014 may be directly fixed to the surface of the tube wall 1012 away from the base plate 1011. In this way, the collimating lens assembly 1014, the tube wall 1012, and the base plate 1011 together form a sealed space.

[0066] The collimating lens group 1014 is located on the side of the light-transmitting sealing layer 1018 away from the base plate 1011. The collimating lens group 1014 includes multiple collimating lenses (not shown in the figure) corresponding one-to-one with the plurality of light-emitting chips 1013, and the number of rows of collimating lenses is the same as the number of rows of light-emitting chips 1013. In the embodiments of this application, each collimating lens in each collimating lens group 1014 can be integrally formed. For example, the collimating lens group 1014 is generally plate-shaped, the side of the collimating lens group 1014 near the base plate 1011 is flat, and the side away from the base plate 1011 has multiple convex arc surfaces, and each of the multiple convex arc surfaces is a collimating lens.

[0067] The light-emitting chip 1013 can emit laser light to the corresponding reflecting prism 1016. The reflecting prism 1016 can reflect the laser light in a direction away from the base plate 1011 (such as the z direction) to the collimating lens corresponding to the light-emitting chip 1013 in the collimating lens group 1014. Then the laser light can be collimated by the collimating lens and emitted.

[0068] Optionally, the laser 101 may also include multiple power supply pins (not shown in the figure). These multiple power supply pins are used to connect to an external power source and can be electrically connected to the light-emitting chip 1013, thereby transmitting current to each light-emitting chip 1013 and triggering each light-emitting chip 1013 to emit laser light.

[0069] The light combining mirror assembly 102 in the embodiments of this application will be described below with reference to the accompanying drawings.

[0070] The beam combining lens assembly 102 may include a plurality of beam combining lenses arranged sequentially along a first direction. Each beam combining lens is located on the side of a row of light-emitting chips 1013 in the laser 101 away from the base plate 1011, and the beam combining lens corresponds to the light-emitting module. Optionally, the orthographic projection of each beam combining lens onto the laser 101 can cover (i.e., completely cover) the collimating lens corresponding to the row of light-emitting chips 1013. Optionally, the orthographic projection of the beam combining lens onto the laser 101 can also cover a portion of the collimating lens, as long as it is ensured that the laser emitted from the collimating lens is directed towards the beam combining lens.

[0071] The beam combining lenses can be tilted, with the laser 101 and the first prism 103 located on the same side of the beam combining lenses. These multiple beam combining lenses can be parallel, and the angle between each of them and the first direction can be 45 degrees. Each light-emitting module can direct its laser beam towards the corresponding beam combining lens, which can reflect the laser beam emitted from the corresponding light-emitting chip, thus turning the laser's transmission path 90 degrees.

[0072] The size of the beam combining lens can be determined based on the size of the laser. Optionally, the size of each beam combining lens can be the same. Optionally, the orthographic projections of each beam combining lens on the first prism 103 can overlap, thus ensuring that the lasers emitted by each row of light-emitting chips 1013 in the laser 101 can be mixed after being reflected by the beam combining lens.

[0073] Please continue to refer to this. Figure 3 The beam combining mirror assembly 102 may include a first beam combining mirror P1 and a second beam combining mirror P2 arranged along the x-direction. The first beam combining mirror P1 can reflect the laser light emitted from the laser 101 toward the first beam combining mirror P1 toward the second beam combining mirror P2. The second beam combining mirror P2 can reflect the laser light emitted from the laser 101 toward the second beam combining mirror P2 toward the first prism 103, and transmit the laser light emitted from the first beam combining mirror P1 toward the second beam combining mirror P2 toward the first prism 103.

[0074] Optionally, the beam combining mirror group 102 with the beam combining mirror furthest from the first prism 103 can be a full-spectrum reflecting mirror; the remaining beam combining mirrors can be dichroic mirrors, used to reflect laser light emitted from the corresponding light-emitting module towards the dichroic mirror, and transmit laser light emitted from the beam combining mirror furthest from the first prism 103. Optionally, the beam combining mirror furthest from the first prism 103 can also be a dichroic mirror; this application embodiment does not limit this. For example, Figure 2 and Figure 3 In the beam combining mirror group 102, the first beam combining mirror P1 can be a total reflection mirror, and the second beam combining mirror P2 can be a dichroic mirror that transmits red light and reflects blue-green light.

[0075] It should be noted that when using laser to form a projected image, if the uniformity of the laser is poor, speckle will appear in the projected image, affecting the display effect. Optionally, in this embodiment, the projection light source 10 may further include a diffuser (not shown in the figure). The diffuser may be located between the second prism 104 and the homogenizing component 106. The diffuser can diffuse and homogenize the laser light incident therein, thereby ensuring good uniformity of the emitted laser light and reducing speckle in the projected image formed based on the laser.

[0076] Optionally, the diffuser in this embodiment can be a fixed diffuser, or it can be a rotatable, vibrating, or movable diffuser. A rotatable diffuser can also be called a diffuser wheel. Optionally, for a fixed diffuser, the projection light source 10 may further include a fixing component (not shown in the figure) corresponding to the diffuser, through which the diffuser can be fixed in position. For example, the fixing component may be a snap-fit ​​structure provided on a housing, used to snap the edge of the diffuser to fix the diffuser. For a rotatable, vibrating, or movable diffuser, the projection light source 10 may further include a driving component (not shown in the figure), which is connected to the diffuser and used to drive the diffuser to move, rotate, or vibrate along the target direction. For example, the diffuser may be driven to move or vibrate back and forth along a direction perpendicular to the transmission direction of the laser. For example, the driving component may be a rotary motor, which may be fixed at the center of the diffuser to drive the diffuser to rotate around its axis.

[0077] In summary, in the projection light source provided in this application embodiment, the laser emitted by the beam combiner group forms a light spot on the incident surface of the first prism with a length greater than its length in the third direction. This second direction is perpendicular to the first direction and parallel to the main cross-section of the first prism. The laser passes through the first prism and then the second prism, and the angle between the incident surface of the second prism and the first direction is greater than the angle between the emitting surface of the first prism and the first direction. Therefore, the length of the light spot formed on the incident surface of the second prism by the laser emitted from the first prism in the second direction is less than the length of the light spot on the emitting surface of the first prism in the second direction. After being emitted through the second prism, the laser beam is compressed in the second direction, resulting in a smaller aspect ratio of the light spot. This facilitates subsequent light collection, improves laser utilization, and further enhances the display effect of the projected image based on the laser.

[0078] Figure 12 This is a schematic diagram of the structure of a projection device provided in an embodiment of this application. For example... Figure 12 As shown, the projection device may include a projection light source 10, a light valve 20, and a lens 30. The projection light source may also include a total internal reflection prism 40 located between the projection light source 10 and the light valve 20. The projection light source can be any of the projection light sources described above, such as... Figures 2 to 9 Any projection light source 10 in the system. The projection light source is used to emit laser light into the light valve, the light valve is used to modulate the emitted laser light and direct it toward the lens, and the lens is used to project the emitted laser light to form a projected image.

[0079] For example, the light valve 20 may include multiple reflective sheets, each of which can be used to form a pixel in the projected image. The light valve 20 can modulate the light by causing the reflective sheets corresponding to pixels that need to be displayed in a bright state to reflect laser light, while the reflective sheets corresponding to pixels that do not need to be displayed in a bright state do not reflect laser light.

[0080] For example, lens 30 may include multiple lenses, which may be arranged sequentially along a certain direction. The laser emitted from light valve 20 can pass sequentially through the multiple lenses in lens 30 to the screen, thereby projecting the laser image onto the screen and displaying the projected image. Lens 30 may be a telephoto lens or an ultra-short-throw lens.

[0081] In this embodiment, the laser emitted by the projection light source in the projection device closely matches the projection requirements of the device, ensuring high laser utilization. Furthermore, the color difference between the various colors of laser emitted by the projection light source is small, guaranteeing uniform mixing of different colors. Therefore, the display effect of the projected image can be improved.

[0082] It should be noted that in the embodiments of this application, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The term "at least one" refers to one or more. The term "multiple" refers to two or more, unless otherwise expressly defined. In this application, the term "at least one of A and B" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, "at least one of A and B" can represent: A existing alone, A and B existing simultaneously, and B existing alone. In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent: A existing alone, A and B existing simultaneously, and B existing alone. "Approximately," "about," "basically," and "close to" mean that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and substantially achieve the technical effect.

[0083] In the accompanying drawings, the dimensions of layers and regions may be exaggerated for clarity. It is also understood that when an element or layer is referred to as being "on" another element or layer, it can be directly on the other element, or there may be intermediate layers. Similar reference numerals throughout indicate similar elements. The projection light source embodiments in this application can be referenced in conjunction with projection device embodiments.

[0084] The above description is merely an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A projection light source, characterized by, The projection light source comprises a laser, a light combination lens group, a first prism, a second prism and a light homogenizing component; The light combination lens group is located on the light emitting side of the laser, and the light combination lens group, the first prism, the second prism and the light homogenizing component are sequentially arranged along a first direction; the laser is configured to emit laser light to the light combination lens group, the light combination lens group is configured to emit the incident laser light to the first prism along the first direction, the first prism is configured to emit the incident laser light to the second prism, the second prism is configured to emit the incident laser light to the light homogenizing component, and the light homogenizing component is configured to emit the incident laser light after homogenization; The first prism and the second prism are both triple prisms, the main section of the first prism is parallel to the main section of the second prism, and the main section of the first prism is parallel to the first direction; on the light incident surface of the first prism, the length of the laser light spot in a second direction is greater than the length in a third direction, the first direction, the second direction and the third direction are perpendicular to each other, and the second direction is parallel to the main section of the first prism; the angle between the light incident surface of the second prism and the first direction is greater than the angle between the light emitting surface of the first prism and the first direction; The first prism satisfies: the incident angle of the laser light incident on the light emitting surface of the first prism is less than the total reflection angle of the first prism, and the difference between the incident angle and the total reflection angle of the first prism is within 5 degrees; The second prism satisfies: the emitting angle of the laser light incident on the light incident surface of the second prism is less than the total reflection angle of the second prism, and the difference between the emitting angle and the total reflection angle of the second prism is within 5 degrees; The shortest distance between the light emitting surface of the first prism and the light incident surface of the second prism is less than 20 mm; The Abbe value of the first prism is greater than the Abbe value of the second prism.

2. The projection light source of claim 1, wherein The first prism and the second prism are both right-angle triple prisms, the right-angle triple prism comprises two right-angle surfaces and an inclined surface, and the two right-angle surfaces and the inclined surface form the main section of the right-angle triple prism; The light emitting surface of the first prism is the inclined surface, and the two right-angle surfaces of the first prism are parallel to the first direction and the second direction, respectively; The light emitting surface of the second prism is the inclined surface, and the two right-angle surfaces of the second prism are parallel to the first direction and the second direction, respectively; or, the light incident surface of the second prism is the right-angle surface, and the light incident surface of the second prism is perpendicular to the first direction.

3. The projection light source of claim 1, wherein One of the first prism and the second prism is a right-angle triple prism, and the main section of the other prism is an acute-angle triangle or an obtuse-angle triangle; Or, the main section of the first prism is an acute-angle triangle or an obtuse-angle triangle, and the main section of the second prism is an acute-angle triangle or an obtuse-angle triangle.

4. The projection light source of claim 1, wherein The material of the first prism is crown glass, and the material of the second prism is flint glass.

5. The projection light source of claim 1, wherein The laser includes two rows of light emitting chips, each row of light emitting chips is arranged along the second direction; one row of light emitting chips in the two rows of light emitting chips includes a plurality of first type light emitting chips, the other row of light emitting chips includes a plurality of second type light emitting chips and a plurality of third type light emitting chips, the wavelengths of the laser emitted by the first type light emitting chips, the second type light emitting chips and the third type light emitting chips decrease in turn; The light combiner set includes two light combiner pieces arranged along the first direction, the two light combiner pieces correspond to the two rows of light emitting chips one by one, each light combiner piece is located on the light emitting side of the corresponding row of light emitting chips, and each light combiner piece is used for reflecting the laser emitted by the corresponding row of light emitting chips along the first direction to the first prism.

6. The projection light source of claim 1, wherein, The light uniformizing component includes an ommatidium lens.

7. A projection apparatus, characterized by comprising: The projection device includes the projection light source in any one of claims 1 to 6, and a light valve and a lens; The projection light source is used for emitting laser to the light valve, the light valve is used for modulating the emitted laser and then emitting the modulated laser to the lens, and the lens is used for projecting the emitted laser to form a projection picture.

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