Laser projection system and laser projector

Abstract

The utility model discloses a laser projection system which comprises at least two light source assemblies, the light source assemblies are used for projecting light rays, the light rays are respectively guided to a fluorescent wheel to be subjected to color processing to form first light rays and second light rays, and the first light rays and the second light rays are staggered in space to improve the optical path difference of the light rays; the first light and the second light are combined into third light through a light combining assembly, color mixing is carried out through a color wheel, homogenizing modulation is carried out through a light homogenizing assembly, and finally the third light is reflected to a projection lens. The utility model further discloses a laser projector comprising the laser projection system. The interference among scattered waves can be effectively reduced through the spatial dislocation design, so that the speckle effect is improved; and meanwhile, the utilization rate of light rays is improved, so that more light rays can be effectively utilized, and the brightness and definition of a projected image are enhanced.

Description

Technical Field

[0001] The present application relates to the field of projection technology, and in particular to a laser projection system and a laser projector. Background Art

[0002] As an advanced display technology, laser projection has been widely used in many fields in recent years. However, with its popularization and in-depth application, the speckle effect has become a key factor restricting its further performance improvement.

[0003] The speckle effect is mainly caused by the coherence of the laser. When the laser is irradiated onto a rough projection screen, the laser will be scattered due to the tiny fluctuations on the screen surface, forming a series of light and dark spots. These spots not only destroy the uniformity and clarity of the image, but also affect the audience's visual experience. Summary of the invention

[0004] In view of this, the present application provides a laser projection system, which improves the optical path difference of the light by spatially displacing the light ray 1 and the light ray 2, and specifically adopts the following technical solutions:

[0005] The laser projection system includes at least two light source assemblies, which are used to project light. The light sources are respectively guided to fluorescent wheels for color processing into light one and light two, and are spatially staggered to improve the optical path difference of the light. A light combining assembly, a color wheel and a light homogenizing assembly are sequentially arranged on the refraction path of the light source assembly. The light one and the light two are combined into light three by the light combining assembly, and the color is mixed by the color wheel, and then homogenized and modulated by the light homogenizing assembly, and finally reflected to the projection lens.

[0006] Preferably, the light source assembly includes a light emitting body, lens one, lens two and a filter. The light is emitted by the light emitting body, first converged by lens one, and then refracted to lens two for further convergence. The light passing through lens two propagates to the filter. The light of a specific wavelength can be reflected onto the fluorescent wheel, reflecting light one or light two. Light one or light two finally passes through the filter and is combined by the light combining assembly.

[0007] Further preferably, a diffusion plate may be further provided between the second lens and the optical filter, and the diffusion plate is used to improve the optical uniformity of the light so that the light can be uniformly refracted on the optical filter.

[0008] Preferably, the light source assembly further comprises lens three, lens four and lens five, the light reflected at the filter is sequentially converged by lens three and lens four to the fluorescent wheel, reflecting light one or light two, light one or light two is sequentially converged by lens four and lens three to the filter, and finally transmitted through lens five, and light one and light two are merged by the light combining assembly.

[0009] Preferably, the light homogenizing component includes a light homogenizing rod, and the light ray three is emitted after total reflection inside the light homogenizing rod, and passes through lens six, lens seven, prism assembly and DMD in sequence, wherein lens six is ​​used to reduce the focal length of the light ray three and increase the numerical aperture of the optical system, and lens seven is used to diffuse the light of the light ray three. The prism assembly performs spectral processing on the light ray three while changing the propagation direction of the light ray three to ensure that the DMD accurately adjusts the intensity of the light ray three, and then the light ray three is reflected by the DMD and passes through the prism assembly to the spatial light modulator for light wave modulation.

[0010] Further preferably, the light homogenizing component further includes at least one reflector, and the reflector is used to change the reflection path of the light 3.

[0011] Still further preferably, two reflectors are provided, both of which are arranged on the path of the light 3 propagating from the lens 7 to the prism assembly.

[0012] Preferably, the light ray three is projected along the α° direction after being reflected for the second time by the reflector.

[0013] More preferably, the α° is 30°~60°.

[0014] The present application also provides a laser projector, comprising the laser projection system as described above.

[0015] Beneficial effects of this application:

[0016] By spatially staggering light ray one and light ray two, it helps to reduce the phase difference caused by different optical paths and effectively reduce the interference between scattered waves, thereby improving the speckle effect and further reducing the possibility of image distortion and color shift; the spatially staggered design can also improve the utilization rate of light, allowing more light to be effectively utilized, thereby enhancing the brightness and clarity of the projected image. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is the laser propagation path of the laser projection system described in the present application;

[0018] Figure 2 is a schematic diagram of the laser projection system described in the present application;

[0019] Figure 3 It is a front view of the laser projection system described in this application.

[0020] In the figure: 1. light source assembly, 11. luminous body, 12. lens one, 13. lens two, 14. filter, 15. diffuser, 16. fluorescent wheel, 17. lens three, 18. lens four, 19. lens five, 2. light combining assembly, 3. color wheel, 4. light homogenizing assembly, 41. light homogenizing rod, 42. lens six, 43. lens seven, 44. reflector, 45. lens eight, 46. lens nine, 47. prism assembly, 48. DMD, 49. spatial light modulator, 5. light one, 6. light two, 7. light three. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described in the present application are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0022] Combination Figure 1~Figure 2 The laser projection system described in the present application is further described, comprising at least two light source components 1, wherein the light source components 1 are used to project light, and the light is respectively guided to the fluorescent wheel 16 for color processing into light 1 5 and light 2 6, and is spatially staggered to improve the optical path difference of the light; a light combining component 2, a color wheel 3 and a light homogenizing component 4 are also sequentially arranged on the refraction path of the light source component 1, and the light 1 5 and the light 2 6 are combined into light 3 7 by the light combining component 2, color mixing is performed by the color wheel 3, and then homogenization modulation is performed by the light homogenizing component 4, and finally reflected to the projection lens.

[0023] It should be noted that the spatial misalignment described in the present application refers to not being in the same propagation plane. Specifically, when the light 1 5 propagates on a horizontal plane, the light 2 6 propagates on a horizontal plane higher or lower than the light 1 5 .

[0024] By spatially displacing light 1 5 and light 2 6, it is helpful to reduce the phase difference caused by different optical paths, effectively reduce the interference between scattered waves, thereby improving the speckle effect, and further reducing the possibility of image distortion and color shift; the spatial dislocation design can also improve the utilization rate of light, so that more light can be effectively utilized, thereby enhancing the brightness and clarity of the projected image.

[0025] The light source assembly 1 includes a light emitting body 11, a lens 1 12, a lens 2 13 and a filter 14. The light is emitted by the light emitting body 11, first converged by the lens 1 12, and then refracted to the lens 2 13 for further convergence. The light passing through the lens 2 13 propagates to the filter 14, and the light of a specific wavelength can be reflected onto the fluorescent wheel 16, reflecting the light 1 5 or the light 2 6. The light 1 5 or the light 2 6 finally passes through the filter 14 and is combined by the light combining assembly 2.

[0026] In this embodiment, the lens 1 12 is a plano-convex lens, and the lens 2 13 is a meniscus lens. The lens 2 13 is used to increase the numerical aperture of the optical system. The light first passes through the plano-convex lens. Due to the convex surface design of the lens 1 12, the light is refracted when passing through and converges to the center of the lens, forming a preliminarily focused light spot; when the light passes through the lens 2 13, the light will be further refracted by the lens, making the light more concentrated and further reducing the light spot.

[0027] It should be noted that the light is monochromatic, the fluorescent wheel 16 is a monochromatic fluorescent wheel 16, and the color of the fluorescent color wheel 3 is different from the color of the light, so the light is mixed when passing through the fluorescent wheel 16, and the reflected light 1 5 or light 2 6 is a mixed color; wherein, the light used to reflect as light 1 5 or light 2 6 can be the same color or different colors. In this embodiment, the light emitted by the light source 11 is one of the three primary colors, and two light source assemblies 1 are provided in the projection system, so the colors of the two fluorescent wheels 16 are the other two of the three primary colors.

[0028] In order to further improve the speckle effect of laser projection, a diffuser 15 may be provided between the lens 2 13 and the filter 14, and the diffuser 15 is used to improve the optical uniformity of the light so that the light can be uniformly refracted on the filter 14. The diffuser 15 scatters the strong light to a larger area, thereby reducing the visibility of the light spot and making the overall refraction effect more uniform and soft.

[0029] The light source assembly 1 also includes lens three 17, lens four 18 and lens five 19. The light reflected from the filter 14 is converged to the fluorescent wheel 16 by the lens three 17 and the lens four 18 in turn, reflecting the light one 5 or the light two 6. The light one 5 or the light two 6 is converged to the filter 14 by the lens four 18 and the lens three 17 in turn, and finally transmitted through the lens five 19. The light one 5 and the light two 6 are combined by the light combining assembly 2.

[0030] In this embodiment, the lens three 17 is a double convex lens, the lens four 18 is a single convex lens, and the lens five 19 is a single convex lens; wherein, the convex surfaces of the lens four 18 and the lens five 19 are both facing the lens three 17; due to the double convex surface design of the lens three 17, the light reflected by the filter 14 is refracted when passing through the lens three 17 and further converges toward the center of the lens three 17, further reducing the focused light spot, and then the light passes through the lens four 18. Since the convex surface of the lens four 18 faces the lens three 17, the light will be further refracted by the lens, making the light more concentrated and further reducing the light spot, at this time, the light one 5 or the light two 6 reflected by the fluorescent wheel 16 is refracted along the center of the lens four 18 and the lens three 17 in turn and focused on the filter 14 to transmit a specific wavelength of light one 5 or light two 6, and then the light one 5 or the light two 6 is refracted by the lens five 19, and finally further converges toward the light combining component 2.

[0031] One of the light 1 5 and the light 2 6 is directly transmitted from the light combining component 2 to the color wheel 3, and the other light is first reflected inside the light combining component 2 until it is parallel to the directly transmitted light and then transmitted to the color wheel 3. The light combining component 2 can be one of an X-prism, a dichroic prism and a polarized light combining prism; the color wheel 3 can be one of a three-color color wheel 3, a four-color color wheel 3, a six-color color wheel 3, a seven-color color wheel 3 and a multi-color segment color wheel 3.

[0032] The light homogenizing component 4 includes a light homogenizing rod 41. The light ray 37 is emitted after being totally reflected inside the light homogenizing rod 41, and passes through a lens 6 42, a lens 7 43, a prism component 47 and a DMD 48 in sequence. The lens 6 42 is used to reduce the focal length of the light ray 37 and increase the numerical aperture of the optical system. The lens 7 43 is used to diffuse the light of the light ray 37. The prism component 47 performs spectral processing on the light ray 37 while changing the propagation direction of the light ray 37 to ensure that the DMD 48 accurately adjusts the intensity of the light ray 37. Then the light ray 37 is reflected by the DMD 48 and passes through the prism component 47 to the spatial light modulator 49 for light wave modulation.

[0033] The prism assembly 47 is formed by a combination of two prisms, and is used to accurately modulate the spatial distribution of the optical signal of the light beam 7, so as to meet the diverse requirements of the projection system for optical signal processing by changing the propagation path and distribution pattern of the laser.

[0034] The light homogenizing assembly 4 further includes at least one reflector 44, which is used to change the reflection path of the light 3 7 to optimize the layout of the laser projection system. In this embodiment, two reflectors 44 are provided, both of which are provided on the path of the light 3 7 propagating from the lens 7 43 to the prism assembly 47; wherein, a lens 8 45 for focusing the light 3 7 is provided between the two reflectors 44, and a lens 9 46 for converging the light is further provided between the reflector 44 and the prism assembly 47; wherein, the lens 8 45 is a meniscus lens, and the lens 9 46 is a biconvex lens.

[0035] It should be noted that if Figure 3 As shown, after the light ray 3 7 is reflected for the second time by the reflector 44, it is projected along the α° direction; specifically, 45°, so as to improve the light utilization rate and make the brightness of the projected image more uniform, avoid the appearance of dark areas or bright areas, and help reduce the loss of light during the propagation process.

[0036] This embodiment also provides a laser projector, including the laser projection system provided above. The laser projection system has the same structural features and functions as the laser projection system in the above embodiment, which will not be described in detail here.

Claims

1. Laser projection system, characterized in that: The invention comprises at least two light source assemblies, wherein the light source assemblies are used to project light, and the light is respectively guided to a fluorescent wheel for color processing into light one and light two, and is spatially staggered to improve the optical path difference of the light; a light combining assembly, a color wheel and a light homogenizing assembly are sequentially arranged on the refraction path of the light source assembly, and the light one and the light two are combined into light three by the light combining assembly, and the color is mixed by the color wheel, and then homogenized and modulated by the light homogenizing assembly, and finally reflected to the projection lens.

2. The laser projection system according to claim 1, characterized in that: The light source assembly includes a light emitting body, lens one, lens two and a filter. The light is emitted by the light emitting body, first converged by lens one, and then refracted to lens two for further convergence. The light passing through lens two propagates to the filter. The light of a specific wavelength can be reflected onto the fluorescent wheel, reflecting light one or light two. Light one or light two is finally transmitted through the filter and combined by the light combining assembly.

3. The laser projection system according to claim 2, characterized in that: A diffusion plate may be further provided between the second lens and the filter. The diffusion plate is used to improve the optical uniformity of the light so that the light can be uniformly refracted on the filter.

4. The laser projection system according to claim 2, characterized in that: The light source assembly also includes lens three, lens four and lens five. The light reflected at the filter is converged to the fluorescent wheel by lens three and lens four in turn, reflecting light one or light two. Light one or light two is converged to the filter by lens four and lens three in turn, and finally transmitted through lens five. Light one and light two are combined by the light combining assembly.

5. The laser projection system according to claim 1, characterized in that: The light homogenizing component includes a light homogenizing rod. The light ray 3 is emitted after being totally reflected inside the light homogenizing rod, and passes through lens 6, lens 7, prism component and DMD in sequence. The lens 6 is used to reduce the focal length of the light ray 3 and increase the numerical aperture of the optical system. The lens 7 is used to diffuse the light of the light ray 3. The prism component performs spectral processing on the light ray 3 while changing the propagation direction of the light ray 3 to ensure that the DMD accurately adjusts the intensity of the light ray 3. Then the light ray 3 is reflected by the DMD and passes through the prism component to the spatial light modulator for light wave modulation.

6. The laser projection system according to claim 5, characterized in that: The light homogenizing component also includes at least one reflector, and the reflector is used to change the reflection path of the light 3.

7. The laser projection system according to claim 6, characterized in that: Two reflectors are provided, both of which are provided on the path of the light 3 propagating from the lens 7 to the prism assembly.

8. The laser projection system according to claim 6, characterized in that: After being reflected by the reflector, the light ray 3 is projected along the α° direction.

9. The laser projection system according to claim 8, characterized in that: The α° is 30°~60°.

10. Laser projector, characterized in that: A laser projection system comprising the laser projection system according to any one of claims 1 to 9.

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