Laser beam combining system applied to multi-primary-color laser projector

Abstract

The invention discloses a laser beam combining system applied to a multi-primary-color laser projector, and belongs to the technical field of laser projectors. Comprising a light source module, a reflector unit and a dispersion element which are sequentially arranged in the light propagation direction. The light source module outputs multiple beams of monochromatic laser with different wavelengths, the reflector unit reflects the multiple beams of monochromatic laser with different wavelengths to the dispersion element at a specific angle, and the dispersion element combines the multiple beams of laser with different wavelengths into one beam. When the principle is utilized, the incident light with different colors is required to be narrow-linewidth laser, while a common LED light source is wide in spectrum, so that the position of an output light field is deviated due to dispersion when the light is incident into a dispersion element, and the system performance is greatly reduced. The light source of the laser projector is narrow-linewidth laser, and the characteristics of the light source just meet the required conditions, so that the laser beam combination system provided by the invention can be used for realizing the beam combination of the laser of the multi-primary-color laser projector.

Description

Technical Field

[0001] The present invention relates to the technical field of laser projectors, and in particular to a laser beam combining system applied to a multi-primary color laser projector. Background Art

[0002] A laser projector is a projection device that uses a laser light source. It uses a laser emitter to emit a laser beam, which is magnified by an optical system and a magnification system composed of lenses, and then is projected onto the projection screen through a projection lens. After the laser beam is expanded by the corresponding optical components and processing chips in the machine, it is transmitted to the X-prism to integrate the three laser beams, and then the projection objective lens transmits the integrated laser beam to the projection screen, completing the entire projection display process.

[0003] In the existing projector light source color mixing system, the design is basically based on the three-primary color beam combining, and is composed of relatively simple reflectors. However, there is currently no better way to combine the beam related to the four primary colors. If the same principle as the three primary colors is still used to achieve beam combining, the reflectivity of the entire reflector to different wavelengths and the overall structure need to be newly optimized. Summary of the invention

[0004] The purpose of the present invention is to provide a laser beam combining system for a multi-primary color laser projector, aiming to solve one of the technical problems existing in the above-mentioned prior art. To achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows:

[0005] A laser beam combining system applied to a multi-primary color laser projector comprises a light source module, a reflector unit and a dispersion element which are sequentially arranged along the light propagation direction; the light source module is used to output multiple beams of monochromatic laser light of different wavelengths, the reflector unit is used to reflect the multiple beams of monochromatic laser light of different wavelengths to the dispersion element at specific angles respectively, and the dispersion element is used to combine the multiple beams of monochromatic laser light of different wavelengths into one beam.

[0006] As a further solution of the present invention: the light source module includes at least a first laser light source, a second laser light source, a third laser light source and a fourth laser light source, the first laser light source outputs a red laser of a specific wavelength, the second laser light source outputs a yellow laser of a specific wavelength, the third laser light source outputs a green laser of a specific wavelength, and the fourth laser light source outputs a blue laser of a specific wavelength.

[0007] As a further solution of the present invention: the wavelength of the red laser is 642 nm, the wavelength of the yellow laser is 576 nm, the wavelength of the green laser is 520 nm, and the wavelength of the blue laser is 450 nm.

[0008] As a further solution of the present invention: the reflector unit includes at least a first reflector, a second reflector, a third reflector and a fourth reflector, the first reflector is used to reflect the red laser to the dispersion element, the second reflector is used to reflect the yellow laser to the dispersion element, the third reflector is used to reflect the green laser to the dispersion element, and the fourth reflector is used to reflect the blue laser to the dispersion element.

[0009] As a further solution of the present invention: the dispersion element is an isosceles trapezoidal dispersion prism with a base angle of 60°.

[0010] As a further solution of the present invention: the reflector unit further includes an angle adjustment component, and the angle adjustment component is used to adjust and control the reflection angles of the first reflector, the second reflector, the third reflector and the fourth reflector respectively.

[0011] As a further solution of the present invention: the angle adjustment component includes at least a first piezoelectric ceramic adjustment device, a second piezoelectric ceramic adjustment device, a third piezoelectric ceramic adjustment device and a fourth piezoelectric ceramic adjustment device, the first piezoelectric ceramic adjustment device is installed on the back of the first reflector, the second piezoelectric ceramic adjustment device is installed on the back of the second reflector, the third piezoelectric ceramic adjustment device is installed on the back of the third reflector, and the fourth piezoelectric ceramic adjustment device is installed on the back of the fourth reflector.

[0012] As a further solution of the present invention: the first piezoelectric ceramic adjustment device, the second piezoelectric ceramic adjustment device, the third piezoelectric ceramic adjustment device and the fourth piezoelectric ceramic adjustment device each include at least two piezoelectric ceramic adjusters, and at least two of the piezoelectric ceramic adjusters are evenly arranged on the back of the first reflector, the second reflector, the third reflector and the fourth reflector.

[0013] As a further solution of the present invention: it also includes a light homogenizing rod, and the light homogenizing rod is arranged at the light output of the dispersion element.

[0014] Beneficial effects of the present invention:

[0015] The present invention provides a laser beam combining system, which includes a light source module, a reflector unit, a dispersion element and a homogenizing rod arranged in sequence along the propagation direction of the light. The light source module outputs multiple beams of monochromatic laser light of different wavelengths, and the reflector unit reflects the multiple beams of monochromatic laser light of different wavelengths to the dispersion element at specific angles, and the dispersion element combines the multiple beams of laser light of different wavelengths into one beam. When using this principle, it is required that the incident light of different colors should be narrow line width laser light, while ordinary LED light sources, due to their wide spectrum, will cause deviations in the output light field position due to their dispersion when incident on the dispersion element, greatly reducing the system performance. The light sources of laser projectors are all narrow line width laser light, and the light source characteristics just meet the required conditions, so the laser beam combining system provided by the present invention can be used to achieve beam combining of multi-primary color laser projector lasers. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings.

[0017] Figure 1 The present invention is a schematic diagram of a laser beam combining system applied to a multi-primary color laser projector.

[0018] In the figure: 1. light source module; 11. first laser light source; 12. second laser light source; 13. third laser light source; 14. fourth laser light source; 2. reflector unit; 21. first reflector; 22. second reflector; 23. third reflector; 24. fourth reflector; 3. dispersion element; 4. angle adjustment assembly; 41. first piezoelectric ceramic adjustment device; 42. second piezoelectric ceramic adjustment device; 43. third piezoelectric ceramic adjustment device; 44. fourth piezoelectric ceramic adjustment device; 5. homogenizing rod. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] In the description of the present invention, it should be understood that terms such as "up", "down", "left", "right", "front" and "back" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, and a specific direction structure and operation. Therefore, they should not be understood as limitations on the present invention.

[0021] In addition, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] See also Figure 1 As shown, an embodiment of the present invention provides a laser beam combining system applied to a multi-primary color laser projector, comprising a light source module 1, a reflector unit 2, a dispersion element 3 and a homogenizing rod 5 which are sequentially arranged along the propagation direction of light.

[0023] The light source module 1 outputs multiple monochromatic laser beams with different wavelengths. The reflector unit 2 reflects the multiple monochromatic laser beams with different wavelengths to the dispersion element 3 at specific angles respectively. The dispersion element 3 then combines the multiple laser beams with different wavelengths into one beam.

[0024] Due to the material dispersion, light of different wavelengths will propagate at different speeds when passing through the dispersion element 3. According to Snell's law, light of different wavelengths incident at the same angle will correspond to different refraction angles:

[0025] n1sinθ1=n2sinθ2

[0026] In the dispersion element 3, the light undergoes two refractions (entering and leaving the dispersion element 3), and each time the light of different wavelengths is deflected at different angles, thus causing dispersion. By utilizing the principle of optical path reversibility, light sources of different wavelengths are incident into the dispersion element 3 at specific angles and positions, and after being refracted by the dispersion element 3, they can be emitted at the same position of the dispersion element 3 at the same angle, thereby realizing the combination of laser beams of different wavelengths.

[0027] When using this principle, it is required that the incident light of different colors should be narrow line width lasers. However, ordinary LED light sources, due to their wide spectrum, will cause deviations in the output light field position due to their dispersion when incident on the dispersion element 3, greatly reducing the system performance. The light sources of laser projectors are all narrow line width lasers, and their light source characteristics just meet the required conditions, so the laser beam combining system provided by the present invention can be used to achieve beam combining of multi-primary color laser projector lasers.

[0028] See also Figure 1As shown, in this embodiment, the light source module 1 is used as a light source of the RGBY four-primary color projector, and at least includes a first laser light source 11, a second laser light source 12, a third laser light source 13 and a fourth laser light source 14. The first laser light source 11 outputs a red laser of a specific wavelength, the second laser light source 12 outputs a yellow laser of a specific wavelength, the third laser light source 13 outputs a green laser of a specific wavelength, and the fourth laser light source 14 outputs a blue laser of a specific wavelength.

[0029] For example, the first laser light source 11 may output a red laser with a wavelength of 642 nm, the second laser light source 12 may output a yellow laser with a wavelength of 576 nm, the third laser light source 13 may output a green laser with a wavelength of 520 nm, and the fourth laser light source 14 may output a blue laser with a wavelength of 450 nm.

[0030] See also Figure 1 As shown, the reflector unit 2 is matched according to the specific situation of the light source module 1. In this embodiment, the reflector unit 2 includes a first reflector 21, a second reflector 22, a third reflector 23 and a fourth reflector 24. The first reflector 21 is a narrow bandwidth reflector with a central wavelength of 642nm, the second reflector 22 is a narrow bandwidth reflector with a central wavelength of 576nm, the third reflector 23 is a narrow bandwidth reflector with a central wavelength of 520nm, and the fourth reflector 24 is a narrow bandwidth reflector with a central wavelength of 450nm. The first reflector 21 reflects the red laser to the dispersion element 3 at a specific angle, the second reflector 22 reflects the yellow laser to the dispersion element 3 at a specific angle, the third reflector 23 reflects the green laser to the dispersion element 3 at a specific angle, and the fourth reflector 24 reflects the blue laser to the dispersion element 3 at a specific angle.

[0031] See also Figure 1 As shown, the dispersion element 3 is an isosceles trapezoidal dispersion prism with a bottom angle of 60°. The material is high-dispersion SF11 glass. After being refracted by the dispersion prism, the lasers of four wavelengths can be emitted at the same angle at the same position on the other side of the dispersion prism, and the mixed output of the four primary color lasers can be achieved after passing through the homogenizing rod 5. In this embodiment, the incident angles of the lasers of four wavelengths relative to the surface of the dispersion prism are: 73.05° (red light), 74.87° (yellow light), 77.00° (green light), 85.67° (blue light).

[0032] Considering that the dispersion prism is highly correlated with the wavelength, and the lasers used in reality all have a certain spectral width and large individual differences, the central wavelength will drift when the working temperature changes. Therefore, we set up an angle adjustment component 4 to control the reflection angles of the first reflector 21, the second reflector 22, the third reflector 23 and the fourth reflector 24, and add a homogenizing rod 5 at the output to increase the anti-interference ability of the system.

[0033] The angle adjustment assembly 4 at least includes a first piezoelectric ceramic adjustment device 41, a second piezoelectric ceramic adjustment device 42, a third piezoelectric ceramic adjustment device 43 and a fourth piezoelectric ceramic adjustment device 44. The first piezoelectric ceramic adjustment device 41 is installed on the back of the first reflector 21, the second piezoelectric ceramic adjustment device 42 is installed on the back of the second reflector 22, the third piezoelectric ceramic adjustment device 43 is installed on the back of the third reflector 23, and the fourth piezoelectric ceramic adjustment device 44 is installed on the back of the fourth reflector 24. Specifically, the first piezoelectric ceramic adjustment device 41, the second piezoelectric ceramic adjustment device 42, the third piezoelectric ceramic adjustment device 43 and the fourth piezoelectric ceramic adjustment device 44 each include at least two piezoelectric ceramic adjusters, and the at least two piezoelectric ceramic adjusters are evenly arranged on the backs of the first reflector 21, the second reflector 22, the third reflector 23 and the fourth reflector 24.

[0034] According to actual needs, the reflection angles of the first reflector 21, the second reflector 22, the third reflector 23 and the fourth reflector 24 can be adjusted separately by a piezoelectric ceramic regulator so that light of different wavelengths is reflected to the dispersion prism at a specific angle.

[0035] The main application scenario of this patent is four-primary color or multi-primary color laser projection equipment. In the existing patents, the projectors are mainly based on three primary colors, and most of them are non-laser projectors, so this technology is basically unavailable. In this embodiment, we only propose a color mixing method of four lasers: 642nm red light, 576nm yellow light, 520nm green light and 450nm blue light, but its scope of use can be a three-primary color system, a four-primary color system or a system with more primary colors.

[0036] The above is a detailed description of the preferred embodiments of the present invention, which cannot be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A laser beam combining system for a multi-primary color laser projector, characterized in that: The invention comprises a light source module (1), a reflector unit (2) and a dispersion element (3) which are arranged in sequence along the propagation direction of light; the light source module (1) is used to output multiple beams of monochromatic laser light of different wavelengths; the reflector unit (2) is used to reflect the multiple beams of monochromatic laser light of different wavelengths to the dispersion element (3) at specific angles; and the dispersion element (3) is used to combine the multiple beams of monochromatic laser light of different wavelengths into one beam.

2. The laser beam combining system for a multi-primary color laser projector according to claim 1, characterized in that: The light source module (1) comprises at least a first laser light source (11), a second laser light source (12), a third laser light source (13) and a fourth laser light source (14); the first laser light source (11) outputs a red laser with a specific wavelength, the second laser light source (12) outputs a yellow laser with a specific wavelength, the third laser light source (13) outputs a green laser with a specific wavelength, and the fourth laser light source (14) outputs a blue laser with a specific wavelength.

3. The laser beam combining system for a multi-primary color laser projector according to claim 2, characterized in that: The wavelength of the red laser is 642 nm, the wavelength of the yellow laser is 576 nm, the wavelength of the green laser is 520 nm, and the wavelength of the blue laser is 450 nm.

4. The laser beam combining system for a multi-primary color laser projector according to claim 2, characterized in that: The reflector unit (2) comprises at least a first reflector (21), a second reflector (22), a third reflector (23) and a fourth reflector (24); the first reflector (21) is used to reflect the red laser to the dispersion element (3); the second reflector (22) is used to reflect the yellow laser to the dispersion element (3); the third reflector (23) is used to reflect the green laser to the dispersion element (3); and the fourth reflector (24) is used to reflect the blue laser to the dispersion element (3).

5. The laser beam combining system for a multi-primary color laser projector according to claim 1, characterized in that: The dispersion element (3) is an isosceles trapezoidal dispersion prism with a base angle of 60°.

6. The laser beam combining system for a multi-primary color laser projector according to claim 4, characterized in that: The reflector unit (2) further comprises an angle adjustment component (4), wherein the angle adjustment component (4) is used to respectively adjust and control the reflection angles of the first reflector (21), the second reflector (22), the third reflector (23) and the fourth reflector (24).

7. The laser beam combining system for a multi-primary color laser projector according to claim 6, characterized in that: The angle adjustment component (4) comprises at least a first piezoelectric ceramic adjustment device (41), a second piezoelectric ceramic adjustment device (42), a third piezoelectric ceramic adjustment device (43) and a fourth piezoelectric ceramic adjustment device (44); the first piezoelectric ceramic adjustment device (41) is mounted on the back of the first reflector (21); the second piezoelectric ceramic adjustment device (42) is mounted on the back of the second reflector (22); the third piezoelectric ceramic adjustment device (43) is mounted on the back of the third reflector (23); and the fourth piezoelectric ceramic adjustment device (44) is mounted on the back of the fourth reflector (24).

8. The laser beam combining system for a multi-primary color laser projector according to claim 7, characterized in that: The first piezoelectric ceramic adjustment device (41), the second piezoelectric ceramic adjustment device (42), the third piezoelectric ceramic adjustment device (43) and the fourth piezoelectric ceramic adjustment device (44) each comprise at least two piezoelectric ceramic adjusters, and the at least two piezoelectric ceramic adjusters are evenly arranged on the backs of the first reflector (21), the second reflector (22), the third reflector (23) and the fourth reflector (24).

9. The laser beam combining system for a multi-primary color laser projector according to claim 1, characterized in that: It also comprises a light homogenizing rod (5), which is arranged at the light output of the dispersion element (3).

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