WO2019196430A1

WO2019196430A1 - Light source system and projection system

Info

Publication number: WO2019196430A1
Application number: PCT/CN2018/118818
Authority: WO
Inventors: 侯海雄; 唐晓峰; 李屹
Original assignee: 深圳光峰科技股份有限公司
Priority date: 2018-04-12
Filing date: 2018-12-03
Publication date: 2019-10-17
Also published as: CN110376833B; CN110376833A

Abstract

A light source system (100, 200, 300, 400) capable of effectively reducing light spots in a projection image, and a projection system. The light source system (100, 200, 300, 400,) comprises: a first laser module (102) used for emitting a laser having a first wavelength range; an area light-splitting piece (111) having a central area (A1) capable of reflecting the laser and a peripheral area (A2) capable of transmitting the laser; a colour wheel (113), at least part of the laser reflected by the central area (A1) entering the colour wheel (113), and the colour wheel (113) reflecting the laser as light having Lambertian distribution; a focusing lens (105) arranged between the first laser module (102) and the area light-splitting piece (111) for focusing the laser onto the central area (A1); a collecting lens set (112) arranged between the area light-splitting piece (111) and the colour wheel (113) for focusing at least part of the laser on the colour wheel (13) and parallelising the light having a Lambertian distribution incident from the colour wheel (113); a square rod (115) having an incident light face and an emergent light face, the parallelised light being focused onto the incident light face by the focusing lens (105); and a light diffusion element (201) positioned between the collecting lens set (112) and the square rod (115).

Description

Light source system and projection system

Technical field

The present invention relates to the field of projection, and in particular to a light source system for a theater and a projection system employing the same.

Background technique

At present, in the field of laser display, with the continuous advancement of phosphor technology, the advantages of laser light source in the field of cinema light source are gradually revealed. Generally, the laser light source system of the projection system used for cinema projection uses a three-primary laser module as a light source, which is a true high-purity light source, which can achieve more than 90% of the human eye identifiable color in nature, which is twice that of the conventional projection light source. the above. Therefore, in addition to having a very high brightness, the laser light source has a higher color gradation performance and a strong image layering. Especially for the playback of stereoscopic movies, the use of laser light sources can greatly enhance the 3D stereoscopic effect. In addition, in terms of service life, the laser light source has a long life, low attenuation, can work continuously for a long time, and does not need to be replaced for a long time, and the service life can be even more than 80,000 hours. In addition, in terms of safety of use, the laser element has no high-voltage structure, no danger of frying light, no mercury pollution, and low daily maintenance cost.

In the existing laser light source system, the red laser light emitted by the red laser module is usually reflected to the collecting lens group before being incident on the projection square rod, and is focused on the color wheel by the collecting lens group, and then reflects the red of the Lambertian distribution. Light. However, since the collecting lens in the collecting lens group has a large curvature, the AR film plated on the surface thereof is relatively difficult to control, and a part of the red laser light is easily reflected when it is incident on the collecting lens. This part of the reflected red laser does not have a Lambertian distribution, and gathers on the light exit surface of the projection square after passing through a series of optical elements, resulting in a "red spot" phenomenon as shown in Fig. 1 on the projection screen (requires description) In order to satisfy the drawing requirements of the drawings, FIG. 1 is a projected image after gradation processing, and the plaques of different gradations shown in the figure are actually "red spots" of different brightness in the projected image. Similarly, there are also staining phenomena of other colors caused by other color lasers.

Summary of the invention

In view of the above problems, the present invention is expected to provide a light source system and a projection system capable of attenuating the phenomenon of a laser projection.

A light source system according to an embodiment of the present invention includes: a first laser module for emitting a laser having a first wavelength range; a region beam splitter, the region beam splitter having a central region and a peripheral region, the central region capable of reflecting the a laser and the peripheral region capable of transmitting the laser; a color wheel to which at least a portion of the laser light reflected by the central region is incident, the color wheel reflecting the incident laser light to have a Lambert Distributed light; a focusing lens disposed between the first laser module and the regional beam splitter to focus the laser light to the central region; collecting a lens group, the collecting lens group being disposed Between the region beam splitter and the color wheel, focusing at least a portion of the laser light to the color wheel and parallelizing the light having a Lambertian distribution incident from the color wheel; The square bar has a light incident surface and a light exit surface, and the parallelized light is concentrated by the focusing lens to the light incident surface of the square bar. The light source system further includes a light diffusing element positioned between the collecting lens group and the square bar.

Preferably, the light diffusing element is a diffusing sheet, and the diffusing sheet is disposed on an optical path near the light incident surface of the square bar.

Alternatively, the light diffusing element is a diffusing sheet, and the diffusing sheet is disposed at a focus of the focusing lens. Further, the light source system is further provided with a relay system disposed on an optical path between the diffusion sheet and the square bar and imaging a spot on the diffusion sheet to the light incident surface.

Alternatively, the light diffusing element is the light incident surface of the square rod, and the light incident surface is processed to have scattering characteristics.

Alternatively, the light diffusing element is the central area of the area beam splitter, the center area being processed to have scattering characteristics. Preferably, the processing is an etching process.

Preferably, the light source system further includes a second laser module for emitting a laser having a second wavelength range different from the first wavelength range. The central region of the area beam splitter is capable of transmitting the laser light having the second wavelength range, and the peripheral region is capable of reflecting the laser light having the second wavelength range as excitation light of the color wheel . Further, the color wheel is capable of converting the incident laser light into a laser light having a third wavelength range. Further, the laser light having the second wavelength range and the laser light emitted from the color wheel passing through the central region of the region beam splitter are respectively concentrated by the focus lens to the square rod The light entrance surface.

Embodiments of the present invention also provide a projection system that includes a light source system as described above.

The light source system and projection system according to the present invention can effectively reduce flares such as erythema in a projected image.

It should be understood that the beneficial effects of the present invention are not limited to the above effects, but may be any of the advantageous effects described herein.

DRAWINGS

Figure 1 shows the "red spot" phenomenon in the projection screen of the prior art;

2 is a schematic view for explaining an example of an optical path of a light source system;

3 is a schematic view showing a region beam splitter used in a light source system;

4 is a light path diagram showing a cause of formation of "erythema" in a light source system;

Figure 5 is a partial schematic view of a collecting lens surface for explaining the cause of "erythema" formation;

FIG. 6 is a schematic view showing a light source system according to an embodiment of the present invention; FIG.

FIG. 7 is a schematic view showing a light source system according to another embodiment of the present invention; FIG.

FIG. 8 is a schematic view showing a light source system according to still another embodiment of the present invention; FIG.

9 is a schematic view showing a region beam splitter of a light source system according to still another embodiment of the present invention.

detailed description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of a light source system and a projection system according to the present invention will be described with reference to the accompanying drawings. It is to be emphasized that all the dimensions in the drawings are only schematic and are not necessarily illustrated in a true scale, and thus are not limiting.

Prior to the specific description of the embodiments of the present invention, the optical path of the conventional light source system and the cause of the occurrence of "erythema" will be briefly explained with reference to FIGS. 2 to 4. It should be noted that, for convenience of explanation, the "erypene" phenomenon caused by the red laser is described herein as an example. However, the light source system and projection system according to the present invention can be used not only to solve the "red spot" phenomenon generated by the red laser, but can also be used to solve the stain phenomenon of other colors due to reasons similar to those described below, such as Green spots caused by green laser light, blue spots caused by blue laser light, and the like.

As shown in FIG. 2, an exemplary light source system 100 includes a blue laser module 101 (corresponding to a second laser module herein) and a red laser module 102 (corresponding to a first laser module herein). The blue laser module 101 may include an upper blue laser module and a lower blue laser module. The blue laser light (corresponding to the laser light having the second wavelength range herein) emitted from the blue laser module 101 is compressed by the reflection of the reflection strip 103 and the mirror 104, and then focused by the focus lens 105 to the square rod 106. . The blue laser light that has been homogenized by the square bar 106 is parallelized by the relay lens 107, the mirror 108, and the relay lens 109, and is then reflected by the anti-blue transparent film 110 to the area beam splitter 111. The optical performance of each region of the area beam splitter 111 is shown in FIG. As shown in FIG. 3, the peripheral area A1 of the area beam splitter 111 is an anti-blue yellow-transparent area that reflects blue light and transmits yellow light, and the central area A2 of the area beam splitter 111 reflects the reflection of red light through the blue light and the green light. Red blue and green areas. On the one hand, the blue laser light incident on the area A1 (anti-blue yellow-transparent area) of the area beam splitter 111 is reflected to the collecting lens group 112, and then focused by the collecting lens group 112 onto the color wheel 113. The blue laser light incident on the color wheel 113 is used as excitation light of the color wheel and is converted into yellow fluorescence having a Lambertian distribution (corresponding to the laser light having the third wavelength range in the present invention). The yellow laser light emitted from the color wheel 113 is parallelized by the collecting lens group 112 and then focused by the focusing lens 114 into the square bar 115. On the other hand, the blue laser light incident on the central area A2 (anti-red blue-green area) of the area beam splitter 111 is transmitted, and then focused onto the diffusion sheet 117 through the collecting lens group 116. By the reflection of the diffusion sheet 117, a blue laser having a Lambertian distribution is generated. This portion of the blue light is reflected by the area A1 of the area beam splitter after being parallelized by the collecting lens group 116, and then focused by the focusing lens 114 into the square bar 115.

The red laser module 102 emits a red laser (corresponding to the laser having the first wavelength range in the present invention). After the red laser light is collimated, it is focused by the red focus lens 118 to the central area A2 of the area beam splitter 111 (anti-red blue-green area). The red laser light is reflected to the collection lens group 112 and then focused by the collection lens group 112 onto the color wheel 113. The color wheel 113 reflects the incident red light to form red light having a Lambertian distribution. The red light having the Lambertian distribution emitted from the color wheel 113 is parallelized by the collecting lens group 112, and then concentrated by the focusing lens 114 to the light incident surface of the square bar 115, and enters the square bar 115. The blue light, the yellow light, and the red light incident on the square bar 115 are uniformly mixed in the square bar 115 by multiple reflections, and then emitted as projection light from the light exit surface of the square bar 115.

In the light source system 100 having the above structure, since the surface curvature of the collecting lens 1121 in the collecting lens group 112 is large, the surface-plated anti-reflection film is liable to be defective. In this case, as shown in FIG. 5, a part of the incident red laser light is easily reflected directly on the surface of the collecting lens 1121. As shown in FIG. 4, this portion of the red laser light directly reflected by the collecting lens 1121 gathers on the light exiting surface of the square bar 115 after passing through a series of optical devices, thereby causing a "red spot" phenomenon on the projection screen.

In order to suppress or dilute the above-mentioned "erythema" phenomenon, the light source system according to the present invention is provided with a light diffusing element in the optical path of the red laser. The light diffusing element has a light diffusing property for diffusing laser light directly reflected by a surface of the collecting lens in the collecting lens group, thereby being capable of improving the uniformity of the laser light directly reflected by the portion, thereby achieving suppression or dilution of the above-mentioned "erythema" "The effect of the phenomenon.

First embodiment

FIG. 6 shows a schematic diagram of an optical path of a light source system 200 in accordance with an embodiment of the present invention. In FIG. 6, the same components as those of the light source system 100 of FIG. 4 are denoted by the same reference numerals. The light source system 200 according to the embodiment of the present invention is different from the light source system 100 shown in FIG. 4 in that a light-scattering plate 201 is provided on the optical path near the light incident surface of the square bar 115 (corresponding to the light diffusing element) ). The diffusion sheet 201 may be, for example, a frosted glass or a diffuse mirror or the like.

The red laser light directly reflected by the collecting lens 1121 passes through the diffusion sheet 201 before entering the square rod 115. The red laser light that originally collected on the light-emitting surface of the square bar 115 is scattered when passing through the diffusion sheet 201. Therefore, the "erythema" caused by this part of the red light is weakened, becomes less obvious, and reaches a controllable range.

Second embodiment

FIG. 7 shows a schematic diagram of an optical path of a light source system 300 in accordance with another embodiment of the present invention. In FIG. 7, the same components as those of the light source system 100 of FIG. 4 are denoted by the same reference numerals. The light source system 300 according to another embodiment of the present invention is different from the light source system 100 system shown in FIG. 4 in that a diffusion sheet 301 and a relay are disposed on an optical path between the focus lens 114 and the square bar 115. System 302. The diffusion sheet 301 is disposed at the focus of the focus lens 114. . The diffusion sheet 301 may be, for example, a frosted glass or a diffuse mirror or the like. The relay system 302 is disposed between the diffusion sheet 301 and the square bar 115 and images the light spot on the diffusion sheet 301 to the light incident surface of the square bar 115. The diffuser 301 and the relay system 302 correspond to the light diffusing elements herein.

In this case, the red laser light directly reflected by the collecting lens 1121 passes through the diffusion sheet 301 and the relay system 302 before entering the square rod 115. The diffusion sheet 301 and the relay system 302 can improve the uniformity of this portion of the red laser light at the light exit surface of the square rod 115. Therefore, the "red spot" caused by this part of red light is diluted.

Third embodiment

FIG. 8 shows a schematic diagram of an optical path of a light source system 400 in accordance with yet another embodiment of the present invention. In FIG. 8, the same components as those of the light source system 100 of FIG. 4 are denoted by the same reference numerals. The light source system 400 according to still another embodiment of the present invention is different from the light source system 100 shown in FIG. 4 in that the square bar 415 replaces the square bar 115, and the light incident surface of the square bar 415 is processed by etching or the like. Has scattering properties. The light incident surface of the square rod 415 having scattering characteristics corresponds to the light diffusing element herein.

According to the present embodiment, since the light incident surface of the square bar 415 is processed to have scattering characteristics (for example, a surface having irregularities after processing), the red laser light directly reflected by the collecting lens 1121 is entered into the square bar 415 while being Into the light surface scattering with scattering properties. Therefore, the uniformity of the portion of the red laser light at the light exit surface of the square rod 415 can be improved, so that the "erythema" is diffused and faded, and becomes inconspicuous.

Fourth embodiment

In addition, the uniformity of the red laser light reflected by the collecting lens 1121 can be improved by other means. For example, FIG. 9 shows a schematic diagram of a region beam splitter 511 of a light source system according to still another embodiment of the present invention. As shown in FIG. 9, the central area A2 of the area beam splitter 511 is processed (for example, etched) to have scattering characteristics. Therefore, the red laser light becomes more uniform while being reflected by the central area A2 of the area beam splitter 511, so that the "red spot" phenomenon is faded or eliminated. The central region of the region beam splitter 511 that has been processed to have scattering characteristics corresponds to the light diffusing element herein.

Furthermore, the projection system according to the invention comprises any of the light source systems described above.

It should be understood that the light source system and projection system according to the present invention are not limited to the specific embodiments described above. According to the actual situation, those skilled in the art can achieve the "red spot" formed by dimming the red laser light reflected by the collecting lens in the collecting lens group by providing other light diffusing elements in the optical path of the red laser. In addition, the light source system using the blue laser module and the red laser module is described in the above embodiment, but the combination of the laser modules of the light source system is not limited thereto, and the laser module of other colors may be combined with the red laser module as needed. . In other words, the first laser module, the second laser module, the first wavelength range, the second wavelength range, and the third wavelength range in the present specification can be selected and combined as needed. Correspondingly, the spectroscopic manner of the peripheral region and the central region of the regional beam splitter may also be changed according to the color of the laser used, as long as the central region is capable of reflecting the laser light of the first wavelength range and the peripheral region is capable of transmitting the first wavelength range. The laser can be.

Furthermore, as described above, the light source system and projection system according to the present invention can be used not only to solve the "red spot" phenomenon generated by the red laser, but also to solve the stain phenomenon of other colors due to similar reasons, such as Green spots caused by green laser light, blue spots caused by blue laser light, and the like. In this case, it is only necessary to apply the various features described above and combinations thereof to the optical path of the corresponding color.

Although the light source system and the projection system according to the present invention have been described above with reference to the accompanying drawings, the present invention is not limited thereto, and those skilled in the art should understand that the substance or scope defined by the appended claims In this case, various changes, combinations, sub-combinations, and variations can be made.

Claims

A light source system, the light source system comprising:

a first laser module for emitting a laser having a first wavelength range;

a region beam splitter, the region beam splitter having a central region and a peripheral region, the central region capable of reflecting the laser light and the peripheral region capable of transmitting the laser light;

a color wheel, at least a portion of the laser light reflected by the central region being incident to the color wheel, the color wheel reflecting the incident laser light into light having a Lambertian distribution;

a focusing lens disposed between the first laser module and the regional beam splitter to focus the laser light to the central region;

Collecting a lens group disposed between the area beam splitter and the color wheel, focusing the at least a portion of the laser light to the color wheel and having an incidence from the color wheel The light parallelization of the primary distribution; and

a square rod having a light incident surface and a light exit surface, wherein the parallelized light is concentrated by the focusing lens to the light incident surface of the square rod,

Wherein, the light source system further comprises a light diffusing element, the light diffusing element being located between the collecting lens group and the square rod.
The light source system according to claim 1, wherein said light diffusing element is a diffusing sheet, and said diffusing sheet is disposed on an optical path in the vicinity of said light incident surface of said square bar.
The light source system according to claim 1, wherein said light diffusing member is a diffusion sheet, said diffusion sheet being disposed at a focus of said focus lens, and

The light source system is further provided with a relay system disposed on an optical path between the diffusion sheet and the square bar and imaging a spot on the diffusion sheet to the light incident surface.
The light source system according to claim 1, wherein said light diffusing element is said light incident surface of said square bar, and said light incident surface is processed to have a scattering characteristic.
The light source system according to claim 1, wherein said light diffusing member is said central region of said region beam splitter, said central region being processed to have scattering characteristics.
A light source system according to claim 4 or 5, wherein the processing is an etching process.
The light source system according to any one of claims 1 to 5, further comprising a second laser module for emitting laser light having a second wavelength range different from the first wavelength range.
The light source system according to claim 7, wherein said central region of said area beam splitter is capable of transmitting said laser light having said second wavelength range, and said peripheral area is capable of reflecting said second The laser light of the wavelength range is used as excitation light for the color wheel.
The light source system according to claim 8, wherein said color wheel is capable of converting said incident excitation light into a laser light having a third wavelength range.
The light source system according to claim 9, wherein said laser light having said second wavelength range and said laser light emitted from said color wheel passing through said central region of said area beam splitter The focusing lens is respectively concentrated by the focusing lens to the light incident surface of the square bar.
A projection system comprising the light source system according to any one of claims 1 to 10.