WO2021037240A1

WO2021037240A1 - Light source and projection device

Info

Publication number: WO2021037240A1
Application number: PCT/CN2020/112245
Authority: WO
Inventors: 郭祖强; 胡飞; 鲁宁
Original assignee: 深圳光峰科技股份有限公司
Priority date: 2019-08-30
Filing date: 2020-08-28
Publication date: 2021-03-04
Also published as: CN112526807A

Abstract

A light source and a projection device. The light source comprises a light-emitting apparatus (10), a wavelength conversion apparatus (20), a polarization conversion apparatus (110) and a light combination apparatus (109), wherein the light-emitting apparatus (10) is used to emit first light transmitted along a first optical path (a) and second light transmitted along a second optical path (b); the wavelength conversion apparatus (20) is arranged on the first optical path (a) and is used to convert the first light into exited light emitted along a third optical path (c); the light combination apparatus (109) is arranged at an intersection of the third optical path (c) and the second optical path (b) and is used to perform light combination processing of the exited light and the second light; the polarization conversion apparatus (110) is arranged at the light emitting side of the light combination apparatus (109) and is used to perform polarization state conversion of the combined light of the exited light and the second light, so that the polarization states of the exited light and the second light after the polarization state conversion are the same. In this way, the invention can solve the 3D projection color cast problem, improve the single-path 3D projection light effect, improve the 3D display brightness, and reduce the cost of a 3D projection device.

Description

Light source and projection equipment

Technical field

This application relates to the field of projection technology, in particular to a light source and projection equipment.

Background technique

With the continuous development of projection display technology, there are more and more applications for 3D display in cinema projectors. The principle of 3D technology is to simulate the actual human eyes to form a 3D stereoscopic picture. The current 3D technologies include active 3D technology, spectral projection technology and passive 3D technology, of which passive 3D technology is the mainstream 3D technology.

Passive 3D technology is a polarization 3D technology that uses the polarization characteristics of light and a liquid crystal controller to achieve 3D display. There are three types of passive 3D technology 3D equipment: single light path, double light path and triple light path. Among them, single optical path 3D equipment has low luminous efficiency, about 15%-16%, single optical path 3D equipment has lower display screen brightness; dual optical path 3D equipment and three optical path 3D equipment have improved luminous efficiency compared to single optical path 3D equipment , But its structure is complicated and the cost is high.

For a cinema projector system with a laser fluorescent light source, the light emitted by the lens is a mixed light of laser and fluorescent light. Due to the different polarization states of laser and fluorescence, when using passive 3D devices, the ratio of laser and fluorescence will change during the polarization process, resulting in deviations in the color of the display screen.

Summary of the invention

The main technical problem solved by this application is to provide a light source and projection equipment to improve the color cast problem of 3D projection, improve the light efficiency of 3D projection, and save the cost of 3D projection equipment.

In order to solve the above technical problems, a technical solution adopted in this application is to provide a light source. The light source includes a light emitting device, a wavelength conversion device, a polarization conversion device, and a light combining device. The light emitting device is used to emit the first light transmitted along the first optical path and the second light transmitted along the second optical path; the wavelength conversion device, It is arranged on the first optical path and used to convert the first light into the received laser light emitted along the third optical path; the light combining device is arranged at the intersection of the third optical path and the second optical path, and is used to contrast the received laser light and the second light path. Perform light combining processing; the polarization conversion device is arranged on the light output side of the light combining device, and is used to convert the polarization state of the combined light of the received laser light and the second light, so that the polarization state conversion of the received laser light and the second light The polarization state is the same.

In order to solve the above technical problems, a technical solution adopted in this application is to provide a light source. The light source includes: a light emitting device for emitting the first light transmitted along the first optical path and the second light transmitted along the second optical path; and the wavelength conversion device is arranged on the first optical path and used for converting the first light into The received laser light emitted from the third optical path; the polarization conversion device is arranged on the third optical path, and is used to convert the polarization state of the received laser light so that the polarization state of the received laser light and the second light after the polarization state conversion are the same; The device is arranged at the intersection of the third optical path and the second optical path, and is used for combining the received laser light and the second light after the polarization state conversion.

In one embodiment, the polarization conversion device is arranged on the light output side of the light combining device or the light output side of the wavelength conversion device, and the polarization conversion device includes: a polarization beam splitting element having a first light entrance surface, a first light exit surface, and a second light exit surface , The first light-incident surface and the first light-emitting surface are disposed opposite to each other, and the second light-emitting surface connects the first light-incident surface and the first light-emitting surface; the light path adjusting element has a connected second A light-incident surface and a third light-emitting surface, the second light-incident surface and the second light-emitting surface are disposed opposite to each other, and the third light-emitting surface and the first light-emitting surface are disposed on the same side; The third light-emitting surface is arranged oppositely; wherein, the polarization beam splitting element receives the received laser light or the combined light of the received laser light and the second light, and divides the received laser light or the combined light of the first polarization The light in the second polarization state is emitted from the first light-emitting surface, and the light in the second polarization state in the received laser light or the combined light is reflected to the second light-emitting surface, and the light in the second polarization state is transmitted to the second light-emitting surface. The optical path adjustment element; the optical path adjustment element emits the light of the second polarization state from the third light exit surface to the polarization conversion element; the polarization conversion element polarizes the light of the second polarization state State conversion, so that the second polarization state after the polarization state conversion is the same as the polarization state of the light in the first polarization state.

In one embodiment, the light source further includes a first lens, which is arranged between the wavelength conversion device and the polarization conversion device, and is used to converge the received laser light emitted by the wavelength conversion device to the polarization beam splitting element.

In one embodiment, the polarization conversion device includes a first fly-eye lens, a second fly-eye lens, and a PCS that are sequentially arranged along the third optical path, and the second fly-eye lens is arranged on a focal plane on the light exit side of the first fly-eye lens.

In one embodiment, the light emitting device includes a first light emitting unit and a second light emitting unit. The first light emitting unit is used to emit the first light transmitted along the first light path, and the second light emitting unit is used to emit the first light transmitted along the second light path. Two lights; wherein the first light includes a first color light in a first wavelength range, and the second light includes at least a first color light in a second wavelength range.

In one embodiment, the second light further includes the second color light or/and the third color light.

In one embodiment, the light-emitting device includes a light-emitting module and a beam splitter, the beam splitter is arranged on the light-emitting side of the light-emitting module, the light-emitting module is used to emit at least the first color light, and the beam splitter is used to guide a part of the first color light to The first light path serves as the first light, and another part of the first color light is guided to the second light path as the second light.

In one embodiment, the light emitting module is also used to emit the second color light or/and the third color light, and the beam splitter is also used to guide the second color light or/and the third color light to the second light path as the second light path. Light.

In one embodiment, the beam splitter is a turntable, and the end surface of the turntable is provided with a beam splitting film distributed along the circumferential direction of the turntable. The beam splitting film is used to reflect a part of the first color light to the first light path, and transmit another part of the first color light and the first light path. The second color light or/and the third color light to the second light path.

In one embodiment, the beam splitter is a turntable, and the end surface of the turntable is provided with a first section and a second section distributed along the circumferential direction of the turntable. The first section is used to reflect the first color light to the first light path and transmit The second color light or/and the third color light reaches the second light path, and the second section is used to transmit the first color light, the second color light or/and the third color light to the second light path.

In order to solve the above technical problems, another technical solution adopted in this application is to provide a projection device. The projection device includes: a light modulator, a lens, and the above-mentioned light source. The light modulator is used to modulate the light beam emitted by the light source according to the image signal to form image light, and the lens is used to project the modulated image light.

The beneficial effects of the embodiments of the present application are: the light source of the embodiments of the present application includes: the light source includes a light-emitting device, a wavelength conversion device, a polarization conversion device, and a light combining device, wherein the light-emitting device is used to emit the first light transmitted along the first optical path and The second light transmitted along the second optical path; the wavelength conversion device is arranged on the first optical path, and is used to convert the first light into the receiving laser light emitted along the third optical path; the light combining device is arranged on the third optical path and the second optical path The intersection of the received laser light and the second light is used to combine the light; the polarization conversion device is arranged on the light output side of the light combining device, and is used to convert the polarization state of the combined light of the received laser light and the second light to make the polarization The polarization state of the received laser light and the second light after the state conversion are the same. In this way, the light source of the embodiment of the present application uses a polarization conversion device to polarize the combined light of the received laser light and the second light, so that the polarization state of the received laser light emitted by the light source is the same as the polarization state of the second light, which can make the projection The combined light of the received laser and the second light emitted by the lens of the device maintains the same polarization state as the laser, which can improve the problem of 3D projection color cast; at the same time, for the projection device with better polarization maintaining effect, the light emitted from the lens The extinction ratio is high, which can improve the single-light path 3D projection light effect, increase the 3D display brightness, and save the cost of 3D equipment.

Description of the drawings

In order to explain the embodiments of the present application or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings that need to be used in the embodiments. Obviously, the drawings in the following description are only some of the present application. Embodiments, for those of ordinary skill in the art, without creative work, other drawings can be obtained based on these drawings.

Fig. 1 is a schematic structural diagram of a first embodiment of a light source according to the present application;

Fig. 2 is a schematic structural diagram of a second embodiment of a light source according to the present application;

Fig. 3 is a schematic structural diagram of a third embodiment of a light source according to the present application;

Fig. 4 is a schematic structural diagram of a fourth embodiment of a light source according to the present application;

Fig. 5 is a schematic structural diagram of a fifth embodiment of a light source according to the present application;

6A is a schematic diagram of the structure of the beam splitter in the light source of the embodiment of FIG. 5;

6B is a schematic side view of the structure of the optical splitter in the embodiment of FIG. 6A;

FIG. 7 is a schematic structural diagram of a beam splitter in a sixth embodiment of the light source of the present application;

Fig. 8 is a schematic structural diagram of a seventh embodiment of a light source according to the present application;

Fig. 9 is a schematic structural diagram of an eighth embodiment of a light source according to the present application;

FIG. 10 is a schematic structural diagram of an embodiment of a projection device according to the present application;

FIG. 11 is a schematic diagram of a specific structure of the polarization conversion device in the light source of the embodiment in FIG. 1.

detailed description

The application will be further described in detail below in conjunction with the drawings and embodiments. It is particularly pointed out that the following examples are only used to illustrate the application, but do not limit the scope of the application. Similarly, the following embodiments are only part of the embodiments of the present application, but not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art without creative work shall fall within the protection scope of the present application.

The orientation or positional relationship indicated by the terms "inner" and "outer" in the description and claims of this application and the above-mentioned drawings are based on the orientation or positional relationship shown in the drawings, or is the customary swing when the application product is used. The orientation or positional relationship is only for the convenience of describing the application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as relevant to the application. limit.

In addition, the terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and It does not have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in a sequence other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations of them are intended to cover non-exclusive inclusions.

This application first proposes a light source, as shown in FIG. 1, which is a schematic structural diagram of the first embodiment of the light source of this application. The light source of this embodiment includes: a light-emitting device 10, a wavelength conversion device 20, a light combining device 109, and a polarization conversion device 110. The light-emitting device 10 is used to emit first light transmitted along the first optical path a and transmitted along the second optical path b. The second light; the wavelength conversion device 20 is arranged on the first optical path a, used to convert the first light into the laser light emitted along the third optical path c; the light combining device 109 is arranged on the third optical path c and the second optical path b The intersection of the wavelength conversion device 20 and the second light emitted by the light-emitting device 10 are used to combine the light; the polarization conversion device 110 is installed on the light-emitting side of the light combining device 109, that is, the polarization conversion device 110 is installed On the photosynthesis path of the received laser light and the second light, it is used to convert the polarization state of the combined light of the received laser light and the second light, so that the polarization states of the received laser light and the second light after the polarization state conversion are the same.

In this embodiment, the wavelength conversion device 20 is a rotating color wheel, and an annularly distributed wavelength conversion material is arranged on the end surface of the color wheel. The wavelength conversion material can convert the first light with a short wavelength into a received laser with a longer wavelength. The wavelength conversion material may be phosphors, quantum dots or other materials used for wavelength conversion. The wavelength conversion device 20 is periodically rotated under the driving of the driving device to relieve the local high temperature condition of the wavelength conversion device 20, which is beneficial to improve the conversion efficiency of the wavelength conversion device 20. Specifically, in this embodiment, the wavelength conversion material is a yellow phosphor material for converting the first light into yellow fluorescence. In other embodiments, the color wheel may also include different sections, and different wavelength conversion materials are set in each section to generate different colors of the laser light. The wavelength conversion device 20 may also be a moving plate carrying a wavelength conversion material, and the moving plate periodically reciprocates under the drive of the driving device.

In this embodiment, the light source further includes a dichroic plate 105 and a collecting lens group 106. The dichroic plate 105 is arranged between the wavelength conversion device 20 and the light combining device 109, and the dichroic plate 105 can reflect and transmit the first light. The collection lens group 106 is arranged between the wavelength conversion device 20 and the dichroic plate 105, and is adjacent to the light-emitting surface of the wavelength conversion device 20, the collection lens group 106 usually includes 2 to 4 lenses for collecting the received laser light . The first light path a includes a first part a1 and a second part a2. The first part a1 is the light path part between the light emitting device 10 and the dichroic plate 105, and the second part a2 is the dichroic plate 105 and the wavelength conversion device 20. The part of the light path between. The first light emitted by the light emitting device 10 is transmitted to the dichroic plate 105 along the first part a1 of the first light path a, is deflected by the reflection of the dichroic plate 105, and is transmitted to the collector along the second part a2 of the first light path a The lens group 106 is condensed to the wavelength conversion device 20 through the collection lens group 106. The wavelength conversion device 20 converts the first light into the received laser light and emits the received laser light along the third optical path. The dichroic plate 105 and the collection lens group 106 Are arranged on the third optical path c, the collection lens group 106 collects the received laser light and emits the received laser light to the dichroic plate 105, the received laser light passes through the dichroic plate 105 and enters the light combining device 109, and the light combining device 109 is set at The intersection of the third optical path c and the second optical path b is used to combine the received laser light transmitted along the third optical path c with the second photosynthetic light transmitted along the second optical path b.

Among them, the light combining device 109 is a regional diaphragm, the middle area of the regional diaphragm is a reflective area, and the outer peripheral area is a transmission area. The second light emitted along the second optical path b is incident on the reflective area of the regional diaphragm and is covered by the regional diaphragm. The sheet is reflected to the photosynthesis path, and the laser light emitted along the third optical path c is transmitted to the photosynthesis path through the transmission area of the regional diaphragm. Since the optical expansion of the received laser light is large, and the optical expansion of the second light is small, the difference in optical expansion between the two can be used to combine light.

In other embodiments, the light combining device can also be realized by other reflective structures. For example, the middle area of the reflective structure is a transmissive area for transmitting the second light, and the outer peripheral area of the reflective structure is a reflective area for reflecting and receiving. Laser, thereby combining the received laser light and the second light; or the middle area of the reflective structure is provided with a through hole area for transmitting the second light, and the non-through hole area is used to reflect the received laser light, thereby combining the received laser light and the second light. Combining light with light, and so on.

Different from the prior art, the light source of this embodiment uses the polarization conversion device 110 to polarize the combined light of the received laser light and the second light, so that the polarization state of the received laser light emitted by the light source is the same as the polarization state of the second light, which can make the The received laser light and the laser light emitted by the lens of the projection device maintain the same polarization state, which can improve the color cast problem of 3D projection; at the same time, for the projection device with better polarization maintaining effect, the light extinction from the lens is relatively high, which can improve Single optical path 3D projection light effect, improve the brightness of 3D display, and save the cost of 3D equipment.

The light-emitting device 10 of this embodiment includes a first light-emitting unit 21 and a second light-emitting unit 22. The first light-emitting unit 21 is used to emit the first light transmitted along the first light path, and the second light-emitting unit 22 is used to emit light along the second light path. Transmission of the second light. Wherein, the first light includes a first color light in a first wavelength range, and the second light includes at least a first color light in a second wavelength range.

Further, the second light also includes the second color light or/and the third color light.

Wherein, the first color light is first blue light, the second color light is green light, and the third color light is red light.

In this embodiment, the first light-emitting unit 21 includes a light-emitting device 101a, a lens 102, a light homogenization module 103, and a lens 104, wherein the lens 102, the light homogenization module 103, and the lens 104 are sequentially arranged on the first part a1 of the first optical path a. The second light-emitting unit 22 includes a light-emitting device 101b, a light-emitting device 101c, a light-emitting device 101d, a dichroic sheet 112a, a dichroic sheet 112b, a dichroic sheet 112c, a lens 113, a scattering wheel 114, a lens 115a and a lens 115b, The lens 113, the scattering wheel 114, the lens 115a and the lens 115b are sequentially arranged on the second optical path b. The light emitting device 101a, the light emitting device 101b, the light emitting device 101c, and the light emitting device 101d are solid light emitting devices, which may be laser diodes (LD) or light emitting diodes (LED). In this embodiment, the light emitting device 101a, the light emitting device 101b, the light emitting device Both 101c and the light-emitting device 101d are laser diodes. Accordingly, the first color light is a first blue laser, the second color light is a green laser, and the third color light is a red laser.

Specifically, the light-emitting device 101a is a blue laser diode, which emits a blue laser with a wavelength of 455 nm, as the first light, is used to excite yellow phosphors to produce yellow fluorescence, with high excitation efficiency; the light-emitting device 101c is a blue laser diode with an emission wavelength It is a 465nm blue laser, which is the blue primary color of the second light, so that its color coordinates can meet the DCI color gamut standard. The light-emitting device 101b is a green excitation diode, which emits a green laser as the green primary color display light, and the light-emitting device 101d is red The light excites the diode, which emits the red laser light as the red primary color display light.

The light-emitting device 101a emits a blue laser with a wavelength of 455nm. The blue laser sequentially passes through the lens 102, the homogenizing module 103, and the lens 104 arranged on the first part a1 of the first optical path a. The sheet 105 is reflected and incident on the collection lens group 106 arranged on the first part a2 of the first optical path a, and is condensed by the collection lens group 106 to the wavelength conversion device 20. The wavelength conversion device 20 converts the received blue laser light into yellow fluorescence. It receives the laser light; the collection lens group 106 collects and converges the yellow fluorescent light and emits it along the third optical path c, and enters the area diaphragm through the dichroic plate 105, and enters the polarization conversion device 110 through the area diaphragm; 101b generates green laser light, the green laser light is reflected by the dichroic plate 112a to the dichroic plate 112b, the dichroic plate 112b transmits the green laser light to the dichroic plate 112c, and the dichroic plate 112c reflects the green laser light to the lens 113; The light-emitting module 101c generates a blue laser with a wavelength of 465 nm, the blue laser with a wavelength of 465 nm is reflected by the dichroic plate 112b to the dichroic plate 112c, and the dichroic plate 112c reflects the blue laser with a wavelength of 465 nm to the lens 113; The light emitting module 101d generates red laser light, which is transmitted to the lens 113 through the dichroic plate 112c; the green laser light, the red laser light and the blue laser light with a wavelength of 465 nm pass through the lens 113 and the scattering wheel 114 sequentially arranged on the second optical path b The lens 115a and the lens 115b form an image on the area diaphragm, and are incident on the polarization conversion device 110 after being reflected by the area diaphragm.

Among them, the outer periphery of the scattering wheel 114 is a scattering sheet with the same scattering angle, and is coated with an anti-reflection (AR) film, which is used to disperse the spots of the blue laser, green laser and red laser with a wavelength of 465nm; homogenization module 103 can be a square rod, double compound eyes, or single compound eyes.

In other embodiments, dichroic films or lenses can be selectively used according to actual needs; the above-mentioned light-emitting modules can be replaced or selected according to projection needs.

Optionally, the light source of this embodiment further includes a light homogenization device 111, specifically, the light homogenization device 111 is disposed on the light exit side of the polarization conversion device 110 to improve the uniformity of light emitted by the light source. The homogenizing device 111 of this embodiment is a square rod. In other embodiments, the light homogenizing device may also use double compound eyes, single compound eyes, diffusers, and the like.

1 and 8, the polarization conversion device 110 of this embodiment is arranged on the light output side of the light combining device 109. The polarization conversion device 110 includes: a polarization splitting element 1101, an optical path adjusting element 1102, and a polarization conversion element 1103. The spectroscopic element 1101 has a first light-incident surface 1202, a first light-emitting surface 1203, and a second light-emitting surface 1204. The first light-incident surface 1202 and the first light-emitting surface 1203 are disposed opposite to each other, and the second light-emitting surface 1204 is connected to the first light-incident surface 1202. And the first light-emitting surface 1203; the light path adjusting element 1102 has a second light-incident surface 1205 and a third light-emitting surface 1206 connected, the second light-incident surface 1205 and the second light-emitting surface 1204 are disposed opposite to each other, and the third light-emitting surface 1206 and the first A light-emitting surface 1203 is set on the same side.

The polarization splitting element 1101 receives the combined light of the received laser light and the second light, and emits the light of the first polarization state in the combined light from the first light exit surface 1203, and reflects the light of the second polarization state in the combined light to the second light. The light exit surface 1204, the light of the second polarization state is transmitted to the light path adjustment element 1102; the light path adjustment element 1102 emits the light of the second polarization state from the third light exit surface 1206 to the polarization conversion element 1103; the polarization conversion element 1103 affects the second polarization state The polarization state of the light is converted, so that the second polarization state after the polarization state conversion is the same as the polarization state of the light in the first polarization state.

The polarization splitting element 1101 is composed of a polarization splitting film (not shown in the figure) and a first prism 1207 and a second prism 1208 adhered to both sides of the polarization splitting film. The first prism 1207 has a first light incident surface 1202 and The second light-emitting surface 1204, the second prism 1208 has a first light-emitting surface 1203, and the polarization splitting film is adhered between the two inclined surfaces of the first prism 1207 and the second prism 1208; the optical path adjustment element 1102 is composed of the third prism 1209 and the reflective element (Not labeled), the third prism 1209 has a second light-incident surface 1205 and a third light-emitting surface 1206 that are connected, and the reflective element is adhered to the inclined surface of the third prism 1209, which is connected to the second light-incident surface 1205 And the third light-emitting surface 1206. The reflection element and the polarization beam splitting film are arranged in parallel and inclined with respect to the optical axis of the received laser light emitted by the wavelength conversion device 106; the polarization conversion element 1103 may be a half-wave plate. The polarization conversion device of this embodiment has a relatively large volume, and the optical power density incident on the polarization conversion device is low, which can effectively improve the reliability of the polarization conversion device.

In this embodiment, the second light includes a green laser, a red laser, and a blue laser with a wavelength of 465 nm. The second light is polarized light with a high extinction ratio. When the polarization direction of the second light is the same as that of the polarization splitting element 1101 When the direction of the transmission axis of the film is parallel, the second light can pass through the polarization splitting film. At this time, the polarization conversion device 110 only performs polarization conversion on the received laser light; when the polarization direction of the second light is the same as that of the polarization splitting film of the polarization splitting element 1101 When the direction of the transmission axis is vertical, the polarization conversion device 110 performs polarization conversion on both the received laser light and the second light. For example, the second light has a second polarization state, and the polarization splitting element 1101 reflects light in the second polarization state and transmits the first polarization. The second light is reflected by the polarization beam splitting element 1101 to the optical path adjusting element 1102, and then reflected by the optical path adjusting element 1102 to the polarization conversion element 1103, and then the polarization conversion element 1103 performs polarization conversion.

Optionally, the light source of this embodiment further includes a first lens 108, which is arranged on the light incident side of the polarization conversion device 110, that is, the first lens 108 is arranged between the wavelength conversion device 20 and the polarization conversion device 110. To converge and collimate the received laser light incident on the polarization conversion device 110 to reduce the volume of the polarization conversion device 110, thereby reducing the volume of the projection equipment.

The polarization conversion device 110 of this embodiment has a large volume, and the light power density incident on the polarization conversion device 110 is low, which can improve the heat dissipation problem of the polarization conversion device 110.

This application further proposes the light source of the second embodiment. As shown in FIG. 2, the difference between the light source of this embodiment and the light source of the embodiment in FIG. The light incident side of the device 111 is used to converge the combined light incident on the light homogenizing device 111.

The laser spot emitted by the wavelength conversion device 20 is transformed into an intermediate image A through the collection lens group 106 and the first lens 108, and the polarization conversion device 110 is at the position of the intermediate image A; the laser spot after polarization conversion by the polarization conversion device 110 passes through the second lens 216 second imaging to the homogenizing device 111.

In this embodiment, the light spot incident on the polarization conversion device 110 is secondarily imaged to the homogenization device 111, which can effectively reduce the volume of the homogenization device 111, thereby reducing the volume of the projection equipment.

This application further proposes the light source of the third embodiment. As shown in FIG. 3, the difference between the light source of this embodiment and the light source of the second embodiment in FIG. 2 is that the polarization conversion device 110 of the light source of this embodiment is arranged on the third optical path c , It is specifically arranged between the wavelength conversion device 20 and the light combining device 109. The polarization conversion device 110 is used to convert the polarization state of the received laser light emitted by the wavelength conversion device 20, and the light combining device 109 is used to convert the polarization of the received laser light and the light emission. The second light emitted by the device 10 is combined. Among them, the first lens 108 and the second lens 216 are arranged between the polarization conversion device 110 and the light combining device 109. The first lens 108 and the second lens 216 secondarily convert the polarization state of the polarization conversion device 110 to the laser spot. Image to the homogenizing device 111.

In other embodiments, the second lens may not be provided.

The received laser light generated by the wavelength conversion device 20 is not polarized light, and the second light is polarized light with a high extinction ratio. The polarization characteristics of the above laser and received laser light can be used to adjust the light path of the light source, so that the polarization conversion device 110 only responds to the received laser light. It is polarized, and the received laser light is converted into polarized light and then combined with the second photosynthetic light.

The polarization conversion device 110 of this embodiment only needs to polarize the received laser light, and the second light does not pass through the polarization conversion device 110, which can prevent the short-wavelength blue laser in the second light from aging the structure of the polarization conversion device 110, and can improve the light source. The reliability of the polarization conversion device 110 is large, which can effectively improve the heat dissipation problem of the polarization conversion device 110.

After the received laser light in the embodiment of FIG. 3 is collimated by the collection lens group 106, the received laser light is converted from an angular distribution to a surface distribution, and the optical expansion amount of the received laser light incident to the polarization conversion device 110 for the polarization conversion process is greatly diluted. In order to solve this technical problem, this application further proposes a light source of the fourth embodiment. As shown in FIG. 4, the difference between the light source of this embodiment and the light source of the embodiment of FIG. 3 is that: of the light source of this embodiment: the first lens 108 is set at the wavelength Between the conversion device 20 and the polarization conversion device 110, the second lens 216 is disposed between the light combining device 109 and the light homogenizing device 111.

In this embodiment, by optimizing the design of the optical path, the laser spot is re-imaged, so that the optical expansion maintenance rate of the intermediate image A of the laser beam incident on the polarization conversion device 110 becomes higher.

This application further proposes a light source of the fifth embodiment. As shown in FIG. 5, the difference between the light source of this embodiment and the light source of the embodiment of FIG. 4 is that the light-emitting device 50 of this embodiment includes a light-emitting module 601 and a beam splitter 614. 614 is arranged on the light emitting side of the light emitting module 601, the light emitting module 601 is used to emit at least the first color light, the beam splitter 641 is used to guide a part of the first color light to the first light path a as the first light, and another part of the first light One color light is guided to the second light path b as the second light.

Further, the light emitting module 601 also emits the second color light or/and the third color, and the beam splitter 641 is used to guide the second color light or/and the third color light to the second light path b as the second light.

Further, the light-emitting device 50 of this embodiment further includes a lens 113, a lens 102, a light homogenizing module 103, a reflecting mirror 613, a lens 104, a lens 115a, and a lens 115b, wherein the lens 102, the light homogenizing module 103, the reflecting mirror 613 and The lens 104 is arranged on the first optical path a, and the lens 115a and the lens 115b are arranged on the second optical path b.

Among them, the light-emitting module 601 is a three-color light-emitting module, including a blue light-emitting module (not shown), a green light-emitting module (not shown), and a red light-emitting module (not shown), which are used to emit blue laser light. , Green laser and red laser. In other embodiments, the light emitting module 601 may be a two-color light emitting module, such as a blue light emitting module and a green light emitting module, or a blue light emitting module and a red light emitting module.

Wherein, as shown in Figs. 6A and 6B, Fig. 6A is a schematic structural diagram of the beam splitter in the light source of the embodiment in Fig. 5; Fig. 6B is a side structural schematic diagram of the beam splitter in the embodiment of Fig. 6A. The beam splitter 614 of this embodiment is a turntable. The end surface of the turntable is provided with a light splitting film distributed along the circumference of the turntable. The light splitting film is used to reflect a part of the first color light to the first light path a, and transmit another part of the first color light and the first light path. The second color light or/and the third color light to the second light path b. Specifically, the light-incident surface of area B of the end face of the turntable is provided with a dichroic film, which can reflect a part of the blue laser light to the first optical path a as the first light, and transmit the green laser, the red laser and the other part of the blue laser. To the second light path b, as the second light. The light-emitting surface of area B is a scattering surface, and an AR film is provided.

The blue laser and green laser emitted by the light-emitting module 601 are converged on the spectroscopic film on the end face of the turntable through the lens 113, and a part of the blue laser is reflected by the spectroscopic film to the first optical path a, and then exits to the mirror 613 through the lens 102 and the homogenizing module 103 The reflector 613 reflects this part of the blue light to the lens 104, and then is reflected by the dichroic plate 105 to the collecting lens group 106 after passing through the lens 104 to form the first light to excite the wavelength conversion device 20; the green laser, the red laser and others A part of the blue laser light is transmitted to the lens 115a through the dichroic film, and then is imaged to the light combining device 109 through the lens 115a and the lens 115b to form the second light.

The blue laser light emitted by the light-emitting module 601 of this embodiment is used as the phosphor excitation light and the blue primary color display light at the same time through the beam splitter 614, avoiding the use of two blue light-emitting modules, which can reduce the volume of the light source, thereby reducing the cost of the projection equipment. volume.

In another embodiment, as shown in FIG. 7, the beam splitter of this embodiment is a turntable, and the end surface of the turntable is provided with a first section C and a second section D distributed along the circumferential direction of the turntable. The first section C Used to reflect the first color light to the first light path a and transmit the second color light or/and the third color light to the second light path b, and the second section D is used to transmit the first color light, the second color light or/ And the third color light to the second light path b.

Specifically, the exit surface of the first section C is a scattering surface and is coated with an AR film. The incident surface of the first section C can reflect the blue laser to the first optical path a, and transmit the red laser and the green laser to the first optical path a. Two optical path b; the incident surface of the second section D is a polished surface, the exit surface is a scattering surface, and the incident surface and the exit surface of the second section D are both coated with AR film, the second section D can transmit the blue laser, The green laser and the red laser are transmitted to the second optical path b. The turntable of this embodiment is divided into two sections, so that the light emitted by the light source has two timings, so it can be used in a projection system of a two-chip spatial light modulator.

In another embodiment, as shown in FIG. 9, the light source of this embodiment uses double compound eyes 208 and a polarization conversion system (PCS) 308 instead of the polarization conversion device 20 of the above embodiment, and the double compound eyes 208 are set in the wavelength conversion. Between the device 20 and the PCS308, the double compound eye 208 includes a first compound eye lens 208a and a second compound eye lens 208b. The PCS is cemented by a number of prisms and half-wave plates. Each prism is provided with a parallel polarization splitting film and reflection The first fly-eye lens, the second fly-eye lens and the PCS308 are arranged in sequence along the third optical path, and the second fly-eye lens is arranged on the focal plane on the light-emitting side of the first fly-eye lens. That is to say, the light beam incident to the first compound eye 208a is divided by the multiple lens units of the first compound eye 208a and focused on the lens unit of the second compound eye 208b, and then the second compound eye 208b emits the array light beam to the PCS 308, and the PCS 308 will enter the The light is converted into polarized light of the same polarization state.

The double compound eye 208 is used to homogenize the received laser light, and the PCS108 is used to perform polarization state conversion on the homogenized laser light, which can improve the PCS308 incident light power density is too high and the problem of poor heat dissipation.

In this embodiment, double compound eyes 208 and PCS308 are used to polarize the received laser light. The degree of optical extension dilution of the received laser light is related to the number of rows of the compound eye unit N, and the degree of optical extension dilution is N/(2N+1). Compared with the polarization conversion device used in the foregoing embodiment to achieve polarization, this embodiment uses dual compound eyes 208 and PCS308 to achieve polarization, which can ensure a higher optical expansion maintenance rate; and has a lower requirement on the number of compound eye rows and is more difficult to manufacture It is small and has high practicability.

The polarization splitting film of the PCS308 of this embodiment is all inclined (downward) in one direction, and the optical axis of the received laser beam after the polarization conversion of the PCS308 is shifted downward, resulting in the subsequent optical axis of the optical device in the laser optical path. Need to pan down.

In order to solve this technical problem, this application proposes another embodiment of the light source. As shown in Figure 10, the PCS408 in this embodiment includes an upper half area and a lower half area, and the polarization splitting film in the upper half area of the PCS408 and The reflective film is tilted upward, and the polarization splitter film and reflective film in the lower half of PCS408 are tilted downward. The optical axis of the laser beam converted by the polarization of the upper half of PCS408 is shifted upward and polarized by the lower half of PCS408. The optical axis of the converted laser beam is shifted downward, but the overall optical axis of the laser beam remains unchanged. Therefore, the optical axis of the optical device in the subsequent laser optical path does not need to be shifted. In addition, the polarization conversion of the PCS408 intermediate zone After the received laser beam is translated upward and downward, the optical density is reduced, so the loss of the received laser beam by the light combining device 109 can be reduced.

This application further proposes a projection device. As shown in FIG. 11, the projection device of this embodiment includes a light modulator 150, a lens 120, and a light source 130. The light source 130 is the light source of the above-mentioned embodiment for emitting light beams. 150 is used to modulate the light beam emitted by the light source 130 according to the image signal to form image light, and the lens 120 is used to project the modulated image light.

Further, the projection device of this embodiment also includes a relay system 140 and other structures. The relay system 140 is used to guide the light beam emitted by the light source 130 to the light modulator 150.

Different from the prior art, the light source in the embodiment of the present application includes: the light source includes a light-emitting device, a wavelength conversion device, a polarization conversion device, and a light combining device. The light-emitting device is used to emit the first light transmitted along the first optical path and the second light along the second optical path. The second light transmitted by the optical path; the wavelength conversion device is arranged on the first optical path to convert the first light into the laser light emitted along the third optical path; the light combining device is arranged at the intersection of the third optical path and the second optical path , Used to combine the received laser light and the second light; the polarization conversion device is arranged on the light exit side of the light combining device, and is used to convert the polarization state of the combined light of the received laser light and the second light, so that the polarization state is converted The polarization state of the received laser light and the second light are the same. In this way, the light source of the embodiment of the present application uses a polarization conversion device to polarize the combined light of the received laser light and the second light, so that the polarization state of the received laser light emitted by the light source is the same as the polarization state of the second light, which can make the projection The combined light of the received laser and the second light emitted by the lens of the device maintains the same polarization state as the laser, which can improve the problem of 3D projection color cast; at the same time, for the projection device with better polarization maintaining effect, the light emitted from the lens The extinction ratio is high, which can improve the single-light path 3D projection light effect, increase the 3D display brightness, and save the cost of 3D equipment.

The above are only implementations of this application, and do not limit the scope of this application. Any equivalent structure or equivalent process transformation made using the content of the description and drawings of this application, or directly or indirectly applied to other related technologies In the same way, all fields are included in the scope of patent protection of this application.

Claims

A light source, characterized in that the light source comprises:

The light emitting device is used to emit the first light transmitted along the first optical path and the second light transmitted along the second optical path;

A wavelength conversion device, arranged on the first optical path, for converting the first light into a received laser light emitted along the third optical path;

The light combining device is arranged at the intersection of the third light path and the second light path, and is used to perform light combining processing on the received laser light and the second light;

The polarization conversion device is arranged on the light exit side of the light combining device, and is used to convert the polarization state of the combined light of the received laser light and the second light, so that the polarization state of the received laser light and the second light after the polarization state conversion is changed. The same state.
A light source, characterized in that the light source comprises:

The light emitting device is used to emit the first light transmitted along the first optical path and the second light transmitted along the second optical path;

A wavelength conversion device, arranged on the first optical path, for converting the first light into a received laser light emitted along the third optical path;

A polarization conversion device, arranged on the third optical path, for converting the polarization state of the received laser light, so that the polarization state of the received laser light after the polarization state conversion is the same as the polarization state of the second light;

The light combining device is arranged at the intersection of the third light path and the second light path, and is used for combining the received laser light and the second light after the polarization state conversion.
The light source according to claim 1 or 2, wherein the polarization conversion device is disposed on the light exit side of the light combining device or the light exit side of the wavelength conversion device, and the polarization conversion device comprises:

The polarization beam splitting element has a first light entrance surface, a first light exit surface, and a second light exit surface. The first light entrance surface and the first light exit surface are disposed opposite to each other, and the second light exit surface is connected to the first light exit surface. A glossy surface and the first light-emitting surface;

The light path adjusting element has a second light-incident surface and a third light-emitting surface that are connected, the second light-incident surface and the second light-emitting surface are disposed opposite to each other, and the third light-emitting surface is the same as the first light-emitting surface. Side setting

The polarization conversion element is arranged opposite to the third light-emitting surface;

Wherein, the polarization beam splitting element receives the received laser light or the combined light of the received laser light and the second light, and transmits the light of the first polarization state in the received laser light or the combined light from the first A light exit surface emits, and the received laser light or the light in the second polarization state in the combined light is reflected to the second light exit surface, and the light in the second polarization state is transmitted to the optical path adjusting element; The optical path adjusting element emits the light in the second polarization state from the third light exit surface to the polarization conversion element; the polarization conversion element performs polarization conversion on the light in the second polarization state so as to be polarized The second polarization state after the state conversion is the same as the polarization state of the light in the first polarization state.
The light source according to claim 3, wherein the light source further comprises a first lens, which is arranged between the wavelength conversion device and the polarization conversion device, and is used to transmit the received laser light emitted by the wavelength conversion device Converge to the polarization beam splitting element.
The light source according to claim 2, wherein the polarization conversion device comprises a first fly-eye lens, a second fly-eye lens and a PCS arranged in sequence along a third optical path, and the second fly-eye lens is arranged on the first fly-eye lens. On the focal plane of the light exit side of the fly-eye lens.
The light source according to claim 1 or 2, wherein the light-emitting device comprises a first light-emitting unit and a second light-emitting unit, and the first light-emitting unit is used to emit the first light transmitted along the first light path. The second light-emitting unit is used to emit the second light transmitted along the second optical path;

Wherein, the first light includes a first color light in a first wavelength range, and the second light includes at least a first color light in a second wavelength range.
The light source according to claim 6, wherein the second light further comprises a second color light or/and a third color light.
The light source according to claim 1 or 2, wherein the light-emitting device comprises a light-emitting module and a beam splitter, the beam splitter is arranged on the light-emitting side of the light-emitting module, and the light-emitting module is used for at least The first color light is emitted, and the beam splitter is used to guide a part of the first color light to the first light path as the first light, and guide another part of the first color light to the second light path as the The second light.
The light source according to claim 8, wherein the light emitting module is also used to emit the second color light or/and the third color light, and the beam splitter is also used to transmit the second color light or/ And the third color light is guided to the second light path as the second light.
The light source according to claim 9, wherein the beam splitter is a turntable, and the end surface of the turntable is provided with a dichroic film distributed along the circumferential direction of the turntable, and the dichroic film is used to reflect a part of the first color The light to the first light path transmits another part of the first color light, the second color light or/and the third color light to the second light path.
The light source according to claim 9, wherein the beam splitter is a turntable, the end surface of the turntable is provided with a first section and a second section distributed along the circumferential direction of the turntable, and the first section Used to reflect the first color light to the first light path and transmit the second color light or/and the third color light to the second light path, and the second section is used to transmit the first light path Color light, the second color light or/and the third color light to the second light path.
A projection device, wherein the projection device comprises: a light modulator, a lens, and the light source according to any one of claims 1 to 11, and the light modulator is used to emit a light beam to the light source according to an image signal Modulation is performed to form image light, and the lens is used to project modulated image light.