Laser light source device and small laser projection device

Abstract

The present application belongs to the field of laser projection, and in particular, relates to a laser light source device and a small laser projection device, wherein the laser light source device comprises a blue laser light source; a diffusion plate, arranged in front of the optical path of the blue laser light source, and used to change the light intensity distribution of the blue laser emitted by the blue laser light source; a dichroic mirror, arranged obliquely in front of the diffusion plate, and used to reflect the blue laser; a 1 / 4 wavelength plate, arranged in front of the optical path of S-polarized light, and used to convert the received blue laser into circularly polarized light; a lens assembly, arranged in the optical path of the circularly polarized light; a composite fluorescent wheel, comprising a substrate, wherein a plurality of blue light reflecting areas are arranged at intervals in the substrate, and yellow fluorescent powder areas are arranged between two adjacent blue light reflecting areas, and the circularly polarized light is converged onto the composite fluorescent wheel through the lens assembly; the composite fluorescent wheel generates yellow light or reflects blue laser, so that the yellow light and the blue laser share a set of optical components, which simplifies the composition of the optical path, reduces the size of the light source device, and reduces the cost.

Description

Technical Field

[0001] The present application belongs to the field of laser projection, and in particular relates to a laser light source device and a small laser projection device. Background Art

[0002] The laser light source currently used in laser projection is usually a solution of monochromatic blue laser plus yellow phosphor or a solution of RGB three-color laser.

[0003] Among them, in the solution of monochromatic blue laser plus yellow phosphor, part of the blue laser emitted by the light source is emitted through an independent blue phosphor light path, and the rest is emitted through an independent yellow phosphor light path. In this structure, the blue laser and the yellow laser are emitted through independent light paths, respectively, and each takes up space, making it impossible to achieve the goal of miniaturization of the laser light source device. In the RGB three-color laser solution, it is composed of independent red, green, and blue light paths, and the light path composition is complex and costly.

[0004] With the above-mentioned existing solutions, it is difficult to achieve the goals of reducing costs and miniaturizing the laser light source device, thus limiting the application of laser light sources in micro-projectors. Utility Model Content

[0005] The purpose of the embodiments of the present application is to provide a laser light source device and a small laser projection device, aiming to solve the technical problems in the prior art that the laser light source device cannot be miniaturized and has high cost.

[0006] To achieve the above-mentioned purpose, the technical solution adopted in the embodiment of the present application is: to provide a laser light source device, including a blue laser light source; a diffusion plate, arranged in front of the optical path of the blue laser light source, used to change the light intensity distribution of the blue laser emitted by the blue laser light source; a dichroic mirror, arranged obliquely in front of the diffusion plate, used to reflect the S-polarized light in the blue laser; a 1 / 4 wavelength plate, arranged in front of the optical path of the S-polarized light, used to convert the received S-polarized light into circularly polarized light; a lens assembly, arranged in the optical path of the circularly polarized light; a composite fluorescent wheel, including a substrate, a plurality of blue light reflection areas are evenly spaced on the substrate, a yellow fluorescent powder area is arranged between two adjacent blue light reflection areas, and the circularly polarized light is converged onto the composite fluorescent wheel through the lens assembly;

[0007] When the circularly polarized light is irradiated on the yellow phosphor area, yellow light is stimulated, and the yellow light enters the lens assembly and is collimated, and then enters the external optical system through the dichroic mirror; when the circularly polarized light is irradiated on the blue light reflection area, it is reflected into the lens assembly, and after being collimated by the lens assembly, it passes through the 1 / 4 wavelength plate, and the 1 / 4 wavelength plate converts the circularly polarized light into P polarized light, and the P polarized light enters the external optical system through the dichroic mirror.

[0008] Specifically, the substrate is circular, a concentric ring is arranged on the substrate, and the blue light reflection area and the yellow phosphor area are both arranged in the concentric ring.

[0009] Specifically, the area of ​​the concentric rings is less than 1 / 2 of the area of ​​the base.

[0010] Specifically, the total area of ​​the blue light reflection regions is smaller than the total area of ​​the yellow phosphor regions.

[0011] Furthermore, the total area of ​​the blue light reflection regions is 17% to 43% of the total area of ​​the yellow phosphor region.

[0012] Specifically, the number of the blue light reflection areas is 4 to 32.

[0013] Specifically, the number of the yellow phosphor areas is 4 to 32.

[0014] Specifically, the blue laser light source emits a blue laser with a wavelength ranging from 449 nm to 461 nm.

[0015] Specifically, the lens assembly includes a first lens and a second lens which are spaced apart from each other, and the areas of the incident surface and the exit surface of the first lens are both larger than the areas of the incident surface and the exit surface of the second lens.

[0016] The present application also provides a small laser projection device, including a laser light source device and an optical system, wherein the laser light source device is the above-mentioned laser light source device.

[0017] In the present application, a blue laser light source emits a blue laser, which changes the light intensity distribution through a diffusion plate, is reflected by a dichroic mirror, and then converted into circularly polarized light through a 1 / 4 wavelength plate, and converges onto a composite fluorescent wheel through a lens assembly. When the circularly polarized light irradiates the blue light reflection area, it is reflected into the lens assembly, and after being collimated by the lens assembly, it passes through a 1 / 4 wavelength plate, which converts the circularly polarized light into P polarized light, and the P polarized light enters the external optical system through a dichroic mirror; when the circularly polarized light irradiates the yellow phosphor area, yellow light is stimulated, and after the yellow light enters the lens assembly and is collimated, it enters the external optical system through a dichroic mirror. The present application uses a blue laser as a light source, which has an extremely high brightness output; at the same time, the blue light path and the yellow light path of the present application share a set of optical components, which simplifies the composition of the light path, reduces the size of the light source device, and reduces the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described 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 paying any creative work.

[0019] Figure 1 A schematic diagram of the structure and optical path of a laser light source device provided in an embodiment of the present application;

[0020] Figure 2 A schematic diagram of a composite fluorescent structure in a laser light source device provided in an embodiment of the present application;

[0021] Among them, the reference numerals in the figure are:

[0022] 1-blue laser light source; 2-diffusion plate; 3-dichroic mirror; 4-1 / 4 wavelength plate; 5-first lens; 6-second lens; 7-composite fluorescent wheel; 71-substrate; 72-blue light reflection area; 73-yellow fluorescent powder area. DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0024] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0025] It should be understood that the directions or positional relationships indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present application.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, and "several" means one or more, unless otherwise clearly and specifically defined.

[0027] Reference Figure 1 - Figure 2 The embodiment of the present application provides a laser light source device, including a blue laser light source 1; a diffusion plate 2, arranged in front of the optical path of the blue laser light source 1, used to change the light intensity distribution of the blue laser emitted by the blue laser light source 1; a dichroic mirror 3, arranged obliquely in front of the diffusion plate 2, used to reflect the S polarized light in the blue laser; a 1 / 4 wavelength plate 4, arranged in front of the optical path of the S polarized light, used to convert the received S polarized light into circularly polarized light; a lens assembly, arranged in the optical path of the circularly polarized light; a composite fluorescent wheel 7, including a substrate 71, a plurality of blue light reflection areas 72 are evenly spaced on the substrate 71, a yellow fluorescent powder area 73 is arranged between two adjacent blue light reflection areas 72, and the circularly polarized light is converged onto the composite fluorescent wheel 7 through the lens assembly;

[0028] When circularly polarized light is irradiated on the yellow phosphor area 73, yellow light is excited, and the yellow light enters the lens assembly and is collimated, and then enters the external optical system through the dichroic mirror 3; when circularly polarized light is irradiated on the blue light reflection area 72, it is reflected and enters the lens assembly, and then passes through the 1 / 4 wavelength plate 4 after being collimated by the lens assembly, and then passes through the 1 / 4 wavelength plate 4, and the 1 / 4 wavelength plate 4 converts the circularly polarized light into P polarized light, and the P polarized light enters the external optical system through the dichroic mirror 3. In the present application, when the light spot passes through the front side of the dichroic mirror 3, the dichroic mirror 3 reflects the S polarized light in the blue laser, and when the light spot passes through the back side of the dichroic mirror 3, the dichroic mirror 3 can pass the blue P polarized light, the yellow S polarized light and the yellow P polarized light; when the light spot passes through the front side of the 1 / 4 wavelength plate 4, the 1 / 4 wavelength plate 4 converts the S polarized light into circularly polarized light, and when the light spot passes through the back side of the 1 / 4 wavelength plate 4, the 1 / 4 wavelength plate 4 converts the circularly polarized light into blue P polarized light.

[0029] In this embodiment, the blue laser light source 1 emits a blue laser, which changes the light intensity distribution through the diffusion plate 2, is reflected by the dichroic mirror 3, and then converted into circularly polarized light through the 1 / 4 wavelength plate 4, and converges on the composite fluorescent wheel 7 through the lens assembly. When the circularly polarized light irradiates the blue light reflection area 72, it is reflected into the lens assembly, and after being collimated by the lens assembly, it passes through the 1 / 4 wavelength plate 4, and the 1 / 4 wavelength plate 4 converts the circularly polarized light into P polarized light, and the P polarized light enters the external optical system through the dichroic mirror; when the circularly polarized light irradiates the yellow phosphor area 73, yellow light is excited, and the yellow light enters the lens assembly and is collimated, and then enters the external optical system through the dichroic mirror 3. The present application uses a blue laser as a light source, which has an extremely high brightness output; at the same time, the blue light path and the yellow light path of the present application share a set of optical components, which simplifies the structure of the light path, reduces the size of the light source device, and reduces the cost.

[0030] Specifically, the base 71 is circular, and a concentric ring is provided on the base 71. The blue light reflection area 72 and the yellow phosphor area 73 are both arranged in the concentric ring. The base 71 is arranged in a circular shape to facilitate the rotation of the composite fluorescent wheel 7. The blue light reflection area 72 and the yellow phosphor area 73 are arranged in the concentric ring and occupy a small space, which is low in cost.

[0031] Specifically, the area of ​​the concentric rings is less than 1 / 2 of the area of ​​the substrate 71 , the blue light reflection area 72 and the yellow phosphor area 73 occupy a small area, and the cost is low.

[0032] Specifically, the total area of ​​the blue light reflection areas 72 is smaller than the total area of ​​the yellow phosphor areas 73. By reasonably setting the total area of ​​the blue light reflection areas 72 and the total area of ​​the yellow phosphor areas 73, the effect of improving the laser brightness is achieved. Preferably, the total area of ​​the blue light reflection areas 72 is 17% to 43% of the total area of ​​the yellow phosphor areas 73.

[0033] In this embodiment, the number of blue light reflection areas 72 is 4, and the number of yellow phosphor areas 73 is 4. Of course, the number of blue light reflection areas 72 and yellow phosphor areas 73 can also be reasonably set according to needs. Preferably, the number of blue light reflection areas 72 is selected between 4 and 32, and the number of yellow phosphor areas 73 can also be selected between 4 and 32.

[0034] Specifically, the wavelength range of the blue laser emitted by the blue laser light source 7 is 449 nm to 461 nm, and the blue laser within this wavelength range has a better effect.

[0035] Specifically, the lens assembly includes a first lens 5 and a second lens 6 which are arranged at an interval. The areas of the incident surface and the exit surface of the first lens 5 are larger than the areas of the incident surface and the exit surface of the second lens 6. On the one hand, the lens assembly converges the blue laser, and on the other hand, collimates the circularly polarized light and the yellow light, so that the circularly polarized light and the yellow light can propagate in the direction of the optical path in a parallel or approximately parallel manner.

[0036] In this embodiment, the blue laser light source 1 emits a blue laser, which changes the light intensity distribution through the diffusion plate 2, is reflected by the dichroic mirror 3, and is then converted into circularly polarized light through the 1 / 4 wavelength plate 4, and is converged on the composite fluorescent wheel 7 through the first lens 5 and the second lens 6 in sequence. When the circularly polarized light irradiates the blue light reflection area 72, it enters the second lens 6 and the first lens 5 in sequence after reflection to be collimated, and then passes through the 1 / 4 wavelength plate 4, which converts the circularly polarized light into P polarized light, and the P polarized light enters the external optical system through the dichroic mirror; when the circularly polarized light irradiates the yellow phosphor area 73, yellow light is excited, and the yellow light enters the second lens 6 and the first lens 5 in sequence to be collimated, and then enters the external optical system through the dichroic mirror 3.

[0037] The present application also provides a small laser projection device, including a laser light source device and an optical system. The laser light source device is the aforementioned laser light source device. The laser light source in the present application is applied to the small laser projection device to make the structure of the laser projection device more compact and realize the miniaturization of the laser device.

[0038] In summary, the above structure simplifies the optical path of the laser light source device, reduces the size of the light source device, and reduces the cost, while also enabling the laser light source to be widely used in micro-projectors.

[0039] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A laser light source device, characterized in that: Blue laser light source; A diffusion plate, disposed just in front of the optical path of the blue laser light source, for changing the light intensity distribution of the blue laser emitted by the blue laser light source; A dichroic mirror, arranged obliquely in front of the diffusion plate, for reflecting the S-polarized light in the blue laser; A quarter wavelength plate, disposed just in front of the optical path of the S-polarized light, for converting the received S-polarized light into circularly polarized light; A lens assembly is arranged on the optical path of the circularly polarized light; A composite fluorescent wheel comprises a substrate, a plurality of blue light reflecting areas are evenly spaced on the substrate, a yellow fluorescent powder area is provided between two adjacent blue light reflecting areas, and the circularly polarized light is converged onto the composite fluorescent wheel through the lens assembly; When the circularly polarized light is irradiated on the blue light reflection area, it is reflected and enters the lens assembly, is collimated by the lens assembly, and then passes through the 1 / 4 wavelength plate. The 1 / 4 wavelength plate converts the circularly polarized light into P polarized light, and the P polarized light enters the external optical system through the dichroic mirror; when the circularly polarized light is irradiated on the yellow phosphor area, yellow light is excited, and the yellow light enters the lens assembly and is collimated, and then enters the external optical system through the dichroic mirror.

2. A laser light source device according to claim 1, characterized in that: The base is circular, and a concentric ring is arranged on the base. The blue light reflection area and the yellow phosphor area are both arranged in the concentric ring.

3. A laser light source device according to claim 2, characterized in that: The area of ​​the concentric rings is less than 1 / 2 of the area of ​​the base.

4. A laser light source device according to claim 1, characterized in that: The total area of ​​the blue light reflection regions is smaller than the total area of ​​the yellow phosphor regions.

5. A laser light source device according to claim 4, characterized in that: The total area of ​​the blue light reflection areas is 17% to 43% of the total area of ​​the yellow phosphor areas.

6. The laser light source device according to claim 1, characterized in that: The number of the blue light reflection areas is 4 to 32.

7. The laser light source device according to claim 1, characterized in that: The number of the yellow phosphor areas is 4 to 32.

8. The laser light source device according to claim 1, characterized in that: The wavelength range of the blue laser emitted by the blue laser light source is 449nm-461nm.

9. The laser light source device according to claim 1, characterized in that: The lens assembly comprises a first lens and a second lens which are arranged at an interval, and the areas of the incident surface and the exit surface of the first lens are both larger than the areas of the incident surface and the exit surface of the second lens.

10. A small laser projection device, comprising a laser light source device and an optical system, characterized in that: The laser light source device is the laser light source device according to any one of claims 1 to 9.

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