CN221039754U

CN221039754U - Optical machine and projector

Info

Publication number: CN221039754U
Application number: CN202322802126.8U
Authority: CN
Inventors: 闫国枫; 陈晓峰
Original assignee: Shenzhen Huole Science and Technology Development Co Ltd
Current assignee: Shenzhen Huole Science and Technology Development Co Ltd
Priority date: 2023-10-18
Filing date: 2023-10-18
Publication date: 2024-05-28
Anticipated expiration: 2033-10-18

Abstract

The present disclosure relates to an optical bench, comprising: the light source module is used for emitting light source light; an imaging chip for modulating the light source into first image light; the projection module is used for receiving the first image light and projecting and emitting second image light; and a light guiding module for guiding the light source light to the imaging chip and for guiding the first image light to the projection module; the projection module further comprises a depolarizer, the depolarizer is used for converting the first image light into second image light, the first image light is polarized light, and the second image light is unpolarized light. The optical machine is beneficial to reducing speckle of image light. The disclosure also relates to a projector comprising the optical machine.

Description

Optical machine and projector

Technical Field

The present disclosure relates to a light engine and a projector including the light engine.

Background

A solution to the problem of how to design a light engine for a projector that is simple in construction, uniform in color, and good in speckle-dissipating effect has been a concern of manufacturers, with a diffuser and dynamic optical elements (e.g., rotating diffuser wheels) to eliminate speckle, with the diffuser rotating to provide random phase to the light converging on the diffuser. However, when the size of the diffusion sheet is smaller, the random phase that can be provided is less, the effect of resolving the speckles is poor, when the size of the diffusion sheet is larger, the large-size rotating wheel is needed to match the diffusion sheet, the size of the optical machine is increased, the actual utilization area of the diffusion sheet is limited, that is, the diffusion sheet with the corresponding size cannot achieve the effect of providing the random phase with the corresponding number. Therefore, the scheme of eliminating the speckles through the diffusion wheel cannot achieve the effects of improving the speckles eliminating effect and reducing the size of the optical machine.

Disclosure of utility model

The present disclosure discloses an optical machine and a projector, which are beneficial to weakening speckle of a projection picture.

In a first aspect, the present disclosure provides an optical engine comprising:

The light source module is used for emitting light source light;

an imaging chip for modulating the light source into first image light;

The projection module is used for receiving the first image light and projecting and emitting second image light; and

A light guiding module for guiding the light source light to the imaging chip and for guiding the first image light to the projection module;

The projection module further comprises a depolarizer, the depolarizer is used for converting the first image light into second image light, the first image light is polarized light, and the second image light is unpolarized light.

The projection module further comprises a lens, and the depolarizer is arranged at a diaphragm of the lens.

The projection module further comprises a lens, and the depolarizer is arranged on one side of the lens, which is close to the light guide module.

The projection module further comprises a lens, and the depolarizer is arranged on one side, away from the light guide module, of the lens.

The depolarizer comprises a first wedge prism and a second wedge prism, and the inclined plane of the first wedge prism and the inclined plane of the second wedge prism are mutually adjacent.

Wherein, the contained angle between the optical axis of first wedge prism and the optical axis of second wedge prism is 45 ± 1.

The light guiding module comprises a polarization beam splitter prism, and is used for guiding the light source light with a first polarization state to the imaging chip and guiding the first image light with a second polarization state to the projection module.

The light guide module further comprises a polaroid, and the polaroid is arranged between the polarization beam splitter prism and the light source module and is used for converting the light source light into light with the first polarization state.

The light source module comprises a laser light source, wherein the laser light source is used for emitting the light source light with the first polarization state.

In a second aspect, the present disclosure further provides a projector, including the optical engine described above.

The optical machine provided by the disclosure comprises the depolarizer through the projection module, and the image light emitted by the imaging chip can be converted into unpolarized light from polarized light, so that speckles formed by projection of the image light are reduced, the optical machine is simple in integral structure, and the size of the optical machine is reduced when the speckle dissipation effect is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings that are needed in the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present disclosure, and other drawings may be obtained according to these drawings without inventive effort to a person of ordinary skill in the art.

Fig. 1 is a schematic structural diagram of an optical machine in an embodiment provided in the present disclosure.

Fig. 2 is a schematic structural diagram of a projection module according to an embodiment of the disclosure.

Fig. 3 is a schematic diagram of an exploded structure of a depolarizer in one embodiment provided by the present disclosure.

Fig. 4 is a schematic structural diagram of an optical machine in another embodiment provided in the present disclosure.

Description of the main reference signs

Ray machine 100

Light source module 10

Imaging chip 30

Projection module 50

Depolarizer 51

First wedge prism 511

First optical axis 512

Second wedge prism 513

Second optical axis 514

Vertical plane 515, 517

Inclined surfaces 516, 518

Lens 53

Light guiding module 70

Polarization beam splitter prism 71

Lens group 73

Polarizing plate 75

Light source light L1

First image light L3

Second image light L5

The application will be further described in the following detailed description in conjunction with the above-described figures.

Detailed Description

The following description of the embodiments of the present disclosure will be made clearly and fully with reference to the accompanying drawings of the embodiments of the present disclosure, in which it is evident that the described embodiments are only some, but not all, of the embodiments of the present disclosure. All other embodiments, which can be made by one of ordinary skill in the art without inventive effort, based on the embodiments in this disclosure are intended to be within the scope of this disclosure.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When a component is considered to be "connected" to another component, it can be directly connected to the other component or intervening components may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only.

It should be noted that the terms "first," "second," and the like in this disclosure are merely used to distinguish between different devices, modules, or units and are not used to define an order or interdependence of functions performed by the devices, modules, or units.

Besides the scheme that the diffusion sheet is matched with the dynamic optical element, the scheme that the incident laser is converged through the light homogenizing rod to be subjected to multiple reflection to be homogenized, so that spots are dissipated is also provided, however, as each laser beam has very good directivity, different laser beams are reflected at different angles in the light homogenizing rod after direct convergence, the reflection times of the laser beams close to the optical axis before convergence are less, the reflection times of the edge laser beams are more, the laser beams cannot be well homogenized, and the projected picture still has the phenomena of spots and the like.

When the optical machine guides the laser beam by the polarization beam splitter prism, the laser beam is usually guided to the imaging chip by the polarization beam splitter prism, modulated into image light including image information by the imaging chip, and emitted through the polarization beam splitter prism. One method is to integrate and homogenize light by using a fly-eye lens, however, the homogenizing effect of the fly-eye lens is not ideal, and the light beam cannot be well homogenized, so that a picture formed by projection still has color spots, and high time and spatial coherence of image light cannot be reduced.

Referring to fig. 1, an optical machine 100 provided in an embodiment of the disclosure includes: the light source module 10, the imaging chip 30, the projection module 50 and the light guide module 70. The light source module 10 is configured to emit light source light L1, and the imaging chip 30 is configured to modulate the light source light L1 into first image light L3. The light guiding module 70 is used for guiding the light source light L1 to the imaging chip 30 and for guiding the first image light L3 to the projection module 50. The projection module 50 includes a depolarizer 51 for converting the first image light L3 into a second image light L5, where the second image light L5 is unpolarized, and the projection module 50 is further configured to project the second image light L5, and the second image light L5 after being projected is irradiated onto a projection plane (not shown) to display an image.

Referring to fig. 2, in the present embodiment, the projection module 50 further includes a lens 53, and the depolarizer 51 is disposed at a stop (not shown) of the lens 53. Specifically, the lens 53 may be a lens or a lens group for receiving the first image light L3 and projecting the second image light L5, and the depolarizer 51 is disposed at a stop of the lens 53 for converting the first image light L3 into the second image light L5. When the depolarizer 51 is disposed at the aperture of the lens 53, the depolarizer 51 has minimal influence on the image light, so that the image quality of the second image light L5 projected is best. In other embodiments, the depolarizer 51 may be disposed at other positions, for example, at a side of the lens 53 close to the light guiding module 70, or at a side of the lens 53 far from the light guiding module 70, which is not limited in the disclosure, so long as the depolarizer 51 is disposed on the light path of the first image light L3 emitted from the light guiding module 70, which is within the scope of the disclosure.

Referring to fig. 2 and 3 together, in the present embodiment, the depolarizer 51 includes a first wedge prism 511 and a second wedge prism 513, a slope 516 of the first wedge prism 511 and a slope 518 of the second wedge prism 513 are adjacent, and an angle between a first optical axis 512 of the first wedge prism 511 and a second optical axis 514 of the second wedge prism 513 is 45 ° ± 1 °.

Specifically, the first wedge prism 511 includes a vertical surface 515 and a slope 516 inclined with respect to the vertical surface 515, a wedge angle is provided between the vertical surface 515 and the slope 516, the second wedge prism 513 includes a vertical surface 517 and a slope 518 inclined with respect to the vertical surface 517, a wedge angle is provided between the vertical surface 517 and the slope 518, and when the slope 516 of the first wedge prism 511 and the slope 518 of the second wedge prism 513 abut each other, the vertical surface 515 of the first wedge prism 511 and the vertical surface 517 of the second wedge prism 513 are parallel to each other. That is, the wedge angle of the first wedge prism 511 and the wedge angle of the second wedge prism 513 are equal. The first image light L3 is vertically incident on the first wedge prism 511, and the second image light L5 is vertically emitted from the second wedge prism 513.

Taking the first wedge prism 511 as an example, when the first image light L3 passes through the first wedge prism 511, since the beam section of the first image light L3 has a certain size, the optical path length of the same beam is different between the vertical plane 515 and the inclined plane 516 of the first wedge prism 511, so that when the first image light L3 exits, different phase delays are generated at the portions of the beam of the first image light L3 corresponding to different thicknesses of the first wedge prism 511, so that the first image light L3 originally having a single polarization direction includes multiple polarization directions after exiting, thereby implementing depolarization. The second wedge prism 513 has the same effect as the first wedge prism 511, and the first image light L3 projected onto the first wedge prism 511 is converted into unpolarized light by the second image light L5 emitted from the second wedge prism 513 after passing through the first wedge prism 511 and the second wedge prism 513 due to a phase delay caused by the difference in thickness.

In this embodiment, the first wedge prism 511 and the second wedge prism 513 are both quartz crystals, and in other embodiments, the first wedge prism 511 and the second wedge prism 513 may be made of other materials, which is not limited in this disclosure. The first optical axis 512 of the first wedge prism 511 and the second optical axis 514 of the second wedge prism 513 are perpendicular to the incident direction of the first image light L3. When the included angle between the first optical axis 512 and the second optical axis 514 is 45 °, the depolarization effect of the first image light L3 passing through the first wedge prism 511 and the second wedge prism 513 is best, and in practical application, a certain error may exist in the included angle between the first optical axis 512 and the second optical axis 514, which is not limited in the disclosure.

The first wedge prism 511 and the second wedge prism 513 may be fixed by gluing, for example, ultraviolet light curing glue, or may be fixed using other means, which is not limited in the present disclosure.

In other embodiments, the depolarizer 51 may be another optical element capable of implementing a depolarizing function, for example, a liquid crystal depolarizer, which is configured to set directions of different liquid crystal molecules, so as to generate different phase delays at different positions of a beam of light, thereby implementing depolarization. Or an optical element composed of two or more quartz crystals glued to each other, a superlens realizing depolarization by providing a nanostructure on a substrate, or the like, for example, the present disclosure is not limited thereto, and any function capable of realizing depolarization is within the scope of the present disclosure.

In the present embodiment, the light source module 10 is a red, green and blue laser light source, and can directly emit the polarized light source light L1. In other embodiments, referring to fig. 4, the light source light L1 emitted from the light source module 10 may also be unpolarized light, and the light guiding module 70 includes a polarizer 75 for converting the light source light L1 into polarized light.

In the present embodiment, the light guiding module 70 includes a polarization beam splitter prism 71 and a lens group 73, and the polarization beam splitter prism 71 may reflect the light source light L1 having the first polarization state and transmit the first image light L3 having the second polarization state, thereby guiding the light source light L1 to the imaging chip 30 and guiding the first image light L3 to the projection module 50. The lens group 73 is used to modulate the light source light L1 to achieve collimation, beam expansion, and the like of the light source light L1. In other embodiments, the light guiding module 70 may also include a light splitting prism such as a total reflection prism, which is not limited by the present disclosure.

The imaging chip 30 is a liquid crystal on silicon (Liquid crystal on Silicon, LCOS) imaging chip, which can change the polarization state of the laser light, when the light source light L1 is reflected by the polarization splitting prism 71 onto the imaging chip 30, the imaging chip 30 changes the polarization state of a part of light to be imaged according to the imaging content, so that the first image light L3 with the second polarization state is reflected by the imaging chip 30 back to the polarization splitting prism 71, and is transmitted and emitted to the projection module 50. In other embodiments, the imaging chip 30 may also be other chips, such as a digital micromirror device (Digital Micromirror Device, DMD) chip, or the like, that converts the light source light L1 having the first polarization state into the first image light L3 having the second polarization state by reflection. When the imaging chip 30 cannot change the polarization state of the light source light L1, a phase retardation wave plate may be further provided between the polarization splitting prism 71 and the imaging chip 30, thereby adjusting the polarization state of the first image light L3.

According to the optical engine 100 provided by the embodiment of the disclosure, the depolarizer 51 is arranged on the projection module 50, so that the first image light L3 with polarization characteristics emitted from the imaging chip 30 can be modulated into the second image light L5 with unpolarized light, and compared with polarized light, the second image light L5 is the unpolarized light, speckles projected on the projection surface can be well suppressed, and the depolarizer 51 and the lens 53 are arranged together, so that the space utilization rate of the optical engine 100 can be improved, and the size of the optical engine 100 is optimized. By arranging the depolarizer 51 on the optical path of the light guide module 70 for emitting the first image light L3, the selection of the optical elements of the light guide module 70 is not affected, for example, the operation of the polarization beam splitter 71 is not affected, which is beneficial to improving the optical element selection surface of the optical engine 100, thereby improving the application surface of the optical engine 100.

The present disclosure also provides a projector including the optical engine 100 in the above embodiment.

The foregoing description is only exemplary embodiments of the present disclosure, and not intended to limit the scope of the disclosure, and all equivalent structures or equivalent processes using the descriptions and the drawings of the present disclosure, or direct or indirect application in other related technical fields are included in the scope of the present disclosure.

Claims

1. A light engine, comprising:

The light source module is used for emitting light source light;

an imaging chip for modulating the light source into first image light;

2. The light engine of claim 1, wherein the projection module further comprises a lens, and the depolarizer is disposed at a stop of the lens.

3. The light engine of claim 1, wherein the projection module further comprises a lens, and the depolarizer is disposed on a side of the lens adjacent to the light guide module.

4. The light engine of claim 1, wherein the projection module further comprises a lens, and the depolarizer is disposed on a side of the lens away from the light guide module.

5. The light engine of claim 1, wherein the depolarizer comprises a first wedge prism and a second wedge prism, the inclined surfaces of the first wedge prism and the second wedge prism abutting each other.

6. The light engine of claim 5, wherein an angle between an optical axis of the first wedge prism and an optical axis of the second wedge prism is 45 ° ± 1 °.

7. The light engine of claim 1, wherein the light directing module includes a polarizing beam splitter prism for directing the source light having a first polarization state to the imaging chip and directing the first image light having a second polarization state to the projection module.

8. The light engine of claim 7, wherein the light guide module further comprises a polarizer disposed between the polarizing prism and the light source module for converting the light source light into light having the first polarization state.

9. The light engine of claim 7, wherein the light source module comprises a laser light source configured to emit the light source light having the first polarization state.

10. A projector, comprising:

the light engine according to any of claims 1-9.