CN113009770B

CN113009770B - Stereoscopic projection system

Info

Publication number: CN113009770B
Application number: CN202110518735.3A
Authority: CN
Inventors: 付伟
Original assignee: Cineappo Laser Cinema Technology Beijing Co ltd
Current assignee: Cineappo Laser Cinema Technology Beijing Co ltd
Priority date: 2020-05-14
Filing date: 2021-05-12
Publication date: 2023-08-29
Anticipated expiration: 2041-05-12
Also published as: CN113009770A; CN111505895A; CN216286146U

Abstract

The present application provides a stereoscopic projection system comprising at least one projection assembly comprising: a projector including a lens assembly for emitting a portion of polarized light; the polarization three-dimensional conversion device comprises a first shell and a light valve arranged in the first shell, wherein the light valve is a single-light-path light valve, and the light valve and the lens assembly are arranged side by side, so that partial polarized light emitted by the projector passes through the light valve and is converted into left-handed circularly polarized light and right-handed circularly polarized light for 3D projection. By using the system, the switching of 2D film projection and 3D film projection can be matched without setting an additional motion mechanism, so that the structure of the whole system becomes simple and the stability is improved.

Description

Stereoscopic projection system

Cross Reference to Related Applications

The present application claims priority from patent application number CN202010407007.0 and entitled "stereoscopic projection system," filed on 14 months 05 in 2020, the entire contents of which are incorporated herein by reference.

Technical Field

The application belongs to the technical field of display, and particularly relates to a three-dimensional projection system.

Background

This section is intended to provide a background or context to the embodiments of the application that are recited in the claims. The description herein is not admitted to be prior art by inclusion in this section.

With the wide application of passive polarization type 3D equipment and the development of automatic projection technology in projection industries such as cinema, an automatic 2D and 3D switching stereoscopic projection system becomes a mainstream technology in the field of 3D projection display. The main idea is that when 3D projection is carried out, a motion mechanism is used for moving the passive polarization 3D equipment into the light path of a projector lens and a metal screen, projector light is changed into left-handed or right-handed circularly polarized light which changes according to the time sequence of a frame sequence after passing through the polarization 3D equipment, and a 3D pattern is generated in human eyes through the metal screen and the 3D glasses. When 2D projection is carried out, the passive polarization three-dimensional conversion equipment is moved out of the light path by the motion mechanism, and the human eye directly sees the 2D pattern projected by the lens.

The moving device in the automatic switching system has the advantages that the structure of the whole projection system is complex, the occupied space is large, the requirement on the installation environment is high, the compatibility of the moving device for special occasion applications such as hoisting is poor, and the manufacturing, transportation and installation costs of the moving mechanism and the support are relatively high. Moreover, the projection lens and the 3D light valve need to move mutually, cannot be sealed, and are exposed in the air to absorb more dust and oil smoke to cause optical interface pollution, so that the 2D and 3D picture quality is affected.

Disclosure of Invention

In view of the above problems in the prior art, a stereoscopic projection system is proposed with which at least one of the above problems can be solved.

The present application provides the following.

There is provided a stereoscopic projection system comprising at least one projection assembly, the projection assembly comprising:

a projector including a lens assembly for emitting a portion of polarized light;

the polarization three-dimensional conversion device comprises a first shell and a light valve arranged in the first shell, wherein the light valve is a single-light-path light valve, the first shell is fixedly connected to the projector, and the light valve and the lens component are arranged side by side, so that partial polarized light emitted by the projector passes through the light valve and is converted into left-handed circularly polarized light and right-handed circularly polarized light for 3D projection.

In one possible embodiment, the stereoscopic projection system includes a single one of the projection assemblies, the system further comprising:

and the control circuit is electrically connected with the projector and the polarization three-dimensional conversion equipment and is used for controlling the light valve to sequentially output the left-handed circularly polarized light and the right-handed circularly polarized light according to frames when the projector performs 3D projection.

In one possible embodiment, the stereoscopic projection system includes two or more projection assemblies, wherein the projectors of the two or more projection assemblies are electrically connected, and the partially polarized light emitted by the projectors of the two or more projection assemblies form the left-handed circularly polarized light and the right-handed circularly polarized light, respectively, after passing through the respective corresponding light valves.

In one possible implementation, the light valve includes:

the liquid crystal projector comprises a phase processor, a polaroid and a liquid crystal phase processor, wherein part of polarized light emitted by the projector sequentially passes through the phase processor, the polaroid and the liquid crystal phase processor, and the polarization direction of polarized light in the part of polarized light after passing through the phase processor is the same as the light transmission axis of the polaroid.

In one possible embodiment, the polarizer is a reflective polarizer.

In one possible embodiment, the polarization degree of the partially polarized light emitted by the projector is greater than 75%.

In one possible embodiment, the first housing is removably fixedly attached to the projector.

In one possible embodiment, the lens assembly includes a second housing and a light-emitting lens disposed inside the second housing; wherein, a sealed space is formed between the light valve and the light-emitting lens.

In one possible embodiment, the light valve is rotatably mounted to an end of the lens assembly, and the light valve is self-rotatably adjusted according to the polarization state of the partially polarized light and the rotational symmetry characteristic of the light valve to cover the current spot range of the partially polarized light emitted by the projector.

In one possible implementation, the light valve does not cover at a single instant all of the spot range of the partially polarized light emitted by the projector, the all of the spot ranges being the sum of the current spot ranges corresponding to each instant.

In one possible embodiment, the minimum distance between the light valve and the lens assembly is determined according to the size of the light valve and the maximum light energy density of the light valve, preferably the size of the light valve is smaller than the size of the light-emitting lens.

In one possible implementation, the control circuit is integrated inside the first housing and is mounted integrally with the light valve.

In one possible embodiment, the phase processor and the polarizer are separated by a first gap, and the polarizer and the liquid crystal phase processor are separated by a second gap; or the phase processor and the polaroid are attached together, and a second gap is reserved between the polaroid and the liquid crystal phase processor; or, a first gap is formed between the phase processor and the polaroid, and the polaroid and the liquid crystal phase processor are attached together.

In one possible implementation manner, the phase processor, the polaroid and the liquid crystal phase processor in the light valve are independently arranged in a single-light-path light valve outside the lens component; or, the phase processor is embedded in the second housing of the lens assembly; or, the phase processor and the polaroid attached to the phase processor are embedded in the second housing of the lens assembly.

In one possible embodiment, the phase processor is formed as an active device, the system further comprising:

the temperature monitoring equipment is used for monitoring the temperature inside the polarization three-dimensional conversion equipment;

and the driving device is used for adjusting the working parameters of the phase processor according to the temperature driving voltage acquired by the temperature monitoring equipment.

The above at least one technical scheme adopted by the embodiment of the application can achieve the following beneficial effects: in this embodiment, the polarization stereo conversion device 20 does not need to be moved, and an additional motion mechanism does not need to be arranged to move the polarization stereo conversion device 20 to match the switching of 2D and 3D film projection, so that the whole system is smaller in size, simple in structure, improved in stability, lower in cost and stronger in maintainability. Smaller light valves in performance result in lower 3D crosstalk and less loss of contrast within the system frame due to the sealing design.

It should be understood that the foregoing description is only an overview of the technical solutions of the present application, so that the technical means of the present application may be more clearly understood and implemented in accordance with the content of the specification. The following specific embodiments of the present application are described in order to make the above and other objects, features and advantages of the present application more comprehensible.

Drawings

The advantages and benefits described herein, as well as other advantages and benefits, will become apparent to those of ordinary skill in the art upon reading the following detailed description of the exemplary embodiments. The drawings are only for purposes of illustrating exemplary embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:

FIG. 1 is a schematic diagram of a stereoscopic projection system according to an embodiment of the application;

FIG. 2 is a schematic diagram of a stand-alone stereoscopic projection system according to an embodiment of the application;

FIG. 3 is a schematic diagram of a light valve according to an embodiment of the present application;

FIG. 4 is a schematic diagram illustrating an optical axis relationship of a light valve according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a stereoscopic projection system according to an embodiment of the application, wherein a control circuit is integrated inside a first housing;

fig. 6a is a schematic structural view of a light valve according to an embodiment of the present application, fig. 6b is a schematic structural view of a light valve according to another embodiment of the present application, and fig. 6c is a schematic structural view of a light valve according to yet another embodiment of the present application;

fig. 7a is a schematic structural view of a stereoscopic projection system according to an embodiment of the present application, fig. 7b is a schematic structural view of a stereoscopic projection system according to another embodiment of the present application, and fig. 7c is a schematic structural view of a stereoscopic projection system according to yet another embodiment of the present application;

FIG. 8 is a schematic diagram of a dual stereoscopic projection system apparatus according to an embodiment of the application;

in the drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

In the present application, it should be understood that the terms "first," "second," and the like, as used in this specification and the claims, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Likewise, the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. "plurality" or "plurality" means two or more. Unless otherwise indicated, the terms "front," "rear," "lower," and/or "upper" and the like are merely for convenience of description and are not limited to one location or one spatial orientation. The word "comprising" or "comprises", and the like, means that elements or items appearing before "comprising" or "comprising" are encompassed by the element or item recited after "comprising" or "comprising" and equivalents thereof, and that other elements or items are not excluded. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items. The terms "comprises" or "comprising" and the like are intended to indicate the presence of features, numbers, steps, acts, components, portions or combinations thereof disclosed in the specification, and are not intended to exclude the possibility of one or more other features, numbers, steps, acts, components, portions or combinations thereof being present.

In addition, it should be noted that, without conflict, the embodiments of the present application and the features of the embodiments may be combined with each other. The application will be described in detail below with reference to the drawings in connection with embodiments.

Referring to fig. 1, embodiments of the present application provide a stereoscopic projection system including at least one projection assembly, which may be a stand-alone stereoscopic projection system, or a dual or multi-machine stereoscopic projection system, without limitation,

wherein, the projection subassembly includes: a projector 10, the projector 10 comprising a lens assembly 11 for emitting a portion of polarized light, which is a combined beam of polarized light and natural light, outwards; a polarization stereo conversion device 20, the polarization stereo conversion device 20 includes a first housing 21 and a light valve 22 disposed inside the first housing 21, the light valve 22 being a single-light path light valve, wherein the light valve 22 is disposed side by side with the lens assembly 11, so that the partial polarized light emitted from the projector 10 when performing 3D projection passes through the light valve to be converted into left-handed circularly polarized light and right-handed circularly polarized light for 3D projection.

The stereoscopic projection system of the application arranges the light valve 22 and the lens component 11 side by side, so that the polarization stereoscopic conversion device 20 is always positioned in the emergent light path of the projector 10, and part of polarized light emitted by the projector 10 passes through the light valve and is converted into left-handed circularly polarized light and right-handed circularly polarized light for 3D projection, thus the polarization stereoscopic conversion device 20 does not need to be moved, and an additional motion mechanism does not need to be arranged to move the polarization stereoscopic conversion device 20 to match the switching of 2D and 3D film projection, thus the structure of the whole system becomes simple, the stability is improved, the requirement on the installation space is small, and the stereoscopic projection system has the advantages of small occupied space, low manufacturing cost, low maintenance cost and the like.

Hereinafter, the present application will be specifically described and illustrated with respect to the case of a stand-alone stereoscopic projection system and the case of a dual or multi-machine stereoscopic projection system, however, it should be understood that the present disclosure should not be limited by the embodiments set forth herein.

Single-machine three-dimensional projection system

In some embodiments, referring to fig. 2, the stereoscopic projection system may be a stand-alone stereoscopic projection system, i.e., the stereoscopic projection system includes a single said projection assembly, and the system may further include: and a control circuit 30, wherein the control circuit 30 is electrically connected with the projector 10 and the polarization stereo conversion device 20, and is used for controlling the light valve 20 to sequentially output the left circularly polarized light and the right circularly polarized light according to frames when the projector 10 performs 3D projection, so that the 3D three-dimensional image projection can be synthesized subsequently.

Alternatively, the control circuit 30 may include a synchronization signal processing unit, a CPU unit, and a polarization modulator driving unit. The synchronization signal processing unit is used for processing the synchronization signal output by the projector 10 and isolating the interference signal introduced by the synchronization signal line of the projector 10. The CPU unit judges the states of the 2D and 3D movies projected by the projector 10 based on the output signals of the synchronization signal processing unit, and decides the operation mode of the polarization modulator driving unit based on the movie states. The polarization modulator drive unit is used to generate drive signals that match the motion picture state of projector 10 to drive the operation of light valve 22. When the projector 10 plays a 3D movie, the polarization modulator driving unit drives the light valve 22 to output left-handed circularly polarized light or right-handed circularly polarized light in frame order, thereby synthesizing a 3D three-dimensional image projection.

In some embodiments, referring to fig. 3, the light valve 22 may specifically include: the liquid crystal display device includes a phase processor 221, a polarizer 222, and a liquid crystal phase processor 223, wherein the phase processor 221 is configured to convert polarized light and partial unpolarized light in partial polarized light into linearly polarized light having a polarization direction equal to a transmission axis of the polarizer 222. The polarizer 222 is used for performing polarization state filtering treatment on the light beam after passing through the phase processor; the liquid crystal phase processor 223 is a group of two liquid crystal quarter-wave retarders attached side by side, and as shown in fig. 4, the light absorption axis X of the linear polarizer 222 bisects the 90-degree angle formed by the two liquid crystal optical axes Y of the liquid crystal phase retarder 223. In other words, part of the polarized light emitted from the projector 10 sequentially passes through the phase processor 221, the polarizer 222, and the liquid crystal phase processor 223, and is converted into left-circularly polarized light and right-circularly polarized light for 3D projection. It will be appreciated that conventional single-path light valves generally include only a polarizer and a liquid crystal retarder, and that the additional use of a phase processor in addition to this has the advantage of matching the direction of a portion of polarized light with the polarizer to increase transmittance. When the polarization ratio of partial polarized light emitted by the projector is greater than 60%, the transmittance of the single-path light valve is equivalent to that of the double-path or the triple-path light valve, and when the polarization ratio of 1 part polarized light emitted by the projector is greater than 90%, the transmittance of the single-path light valve is higher than that of the traditional double-path or triple-path light valve.

In some embodiments, the first housing 21 is detachably and fixedly connected to the projector 10, so that the polarization stereo conversion device 20 can be fixedly installed on the projector 10 when 2D and 3D projection is required, and the connection between the polarization stereo conversion device 20 and the projector 10 is dust-proof sealed, so that the purpose of reducing the exposed pollution of the lens assembly 11 and the light valve 22 can be achieved. And the polarization stereoscopic conversion device 20 is detached from the projector for use when only 2D projection is performed.

It can be understood that the polarization stereo conversion device 20 may be an ultra-high light efficiency 3D device, when the light emitted from the projector 10 is high in transmittance (typically, greater than 80%) at the position of the polarization stereo conversion device 20, the 2D projection can meet the requirement of projection brightness without moving the polarization stereo conversion device 20 out of the optical path of the projector 10, and at this time, the connection position between the polarization stereo conversion device 20 and the projector 10 is dust-proof sealed, so as to achieve the purpose of reducing the exposed pollution of the lens assembly 11 and the light valve 22.

In some embodiments, the polarizer 222 may be a reflective polarizer, so that a heat dissipation effect of the polarizer may be ensured.

In some embodiments, to ensure that projector 10 meets the lighting requirements of 2D and 3D presentations after being fixedly connected to polarization stereoscopic conversion device 20, the polarization of the partially polarized light emitted by the projector is greater than 75%. The light valve can generate high transmittance, realize the maximum utilization of light and not waste too much light.

In some embodiments, referring to fig. 1, the lens assembly 11 includes a second housing 111 and a light-emitting lens 112 disposed inside the second housing 111; wherein a sealed space is formed between the light valve 22 and the light-emitting lens 112.

Referring to fig. 1, the projector 10 specifically includes a body 12 and a lens assembly 11, the lens assembly 11 including a second housing 111 and a lens group disposed inside the second housing 111 and juxtaposed with a light valve 22. In the present embodiment, the lens group may include a plurality of lenses, and the kind and the number of lenses may be set according to actual needs, which is not limited in the present application. It will be appreciated that only the outermost light-emitting lens 112 of the lens group is shown, and the light-emitting lens 112 is disposed in the second housing 111 at a position away from the main body 12. One end of the second housing 111 is fixedly connected to the body 12, and the other end is fixedly and hermetically connected to the first housing 21. Alternatively, the first housing 21 may be connected to an end portion, an outer side wall, or directly connected to the body 12 of the second housing 111 to achieve the above-mentioned sealing connection, and the embodiment is not particularly limited. The other end of the second housing 111 is fixedly and hermetically connected to the first housing 21 of the polarization stereo conversion device 20 such that the light-emitting lens 112 is arranged side by side with the light valve 22. The lens assembly 11 includes a second housing 111 and a light-emitting lens 112 disposed inside the second housing 111; wherein the first housing is connected to an end of the second housing, an outer sidewall, or an end of the body. Thereby forming a sealed space between the light valve and the light-emitting lens. Thus, the problem of intra-frame contrast attenuation caused by dust accumulation during projection can be solved. For the mobile scheme, 3 faces are easy to accumulate ash when 3D projection is carried out, and the contrast ratio in the frame is affected. And after sealed connection, only one face is prone to dust accumulation when 3D projection applications are performed. In addition, the 3D projection is less than the movable dust accumulation surface, and the influence of dust accumulation on the intra-frame contrast can be reduced compared with the movable type. In addition, the polarization stereo conversion device 20 is in sealing connection with the projector 10 to realize sealing installation, so that the lens assembly 11 and the light valve 22 adjacent to the lens assembly are not polluted by the environment, the attenuation of brightness and contrast is reduced, and the polarization stereo conversion device is beneficial to ensuring the stability of image quality.

In some embodiments, the light valve 22 is rotatably mounted to an end of the lens assembly 11, specifically, the first housing 21 may be rotatably mounted to an end of the second housing 111, an outer side wall, or directly connected to the body 12, and the light valve 22 is disposed inside the first housing 21 and may be self-rotated following the rotation of the first housing 21, but it is also possible to rotate the light valve 22 along the axis of the lens assembly by a rotating member. The light valve 22 performs self-rotation adjustment according to the polarization state of the partial polarized light and the rotation symmetry characteristic of the light valve, so that the light valve has the same influence on the emergent partial polarized light before and after rotation, the light valve 22 can cover the current light spot range of the partial polarized light emitted by the projector by using rotation displacement, and the same displacement range of light spots on a lens or the light valve is satisfied, so that the light valve can have the same efficacy as a large light valve covering all areas of light spot displacement. The light valve 22 does not cover the full spot range of the partially polarized light emitted by the projector at a single instant, the full spot range being the sum of the current spot ranges corresponding to each instant. Preferably, the size of the light valve 22 is such that the smallest size that enables the light valve 22 to cover each current spot range with rotational displacement.

In some embodiments, the minimum distance between the light valve and the lens assembly is determined based on the size of the light valve and the maximum optical energy density of the light valve. It will be appreciated that in conventional single-path light valves, the distance between the light valve and the light-emitting lens is typically 100mm or more, and the light valve width is greater than the lens outer diameter. In the present embodiment, the distance L between the light valve and the light-emitting lens is greater than Lmin, wherein when the distance between the light valve 22 and the end face of the light-emitting lens is greater than Lmin, the optical energy density on the light valve 22 is the maximum empirical value that the light valve can withstand. The size of the light valve is smaller than that of the light emergent lens, so that the light emergent lens still has a good appearance after a single-light-path three-dimensional conversion system is added.

In some embodiments, referring to fig. 5, the control circuit 30 may be integrated inside the first housing and integrally mounted with the light valve, and the control circuit 30 is configured to drive the light valve to operate. It will be appreciated that the closer the control circuit 30 and the drive board and light valve FPC (flexible circuit board) wires therein, the more resistant to external interference. And the integrated installation can ensure the matching problem of the light valve parameters and the driving parameters, and is convenient for production, transportation and installation, thereby being beneficial to saving the cost.

Alternatively, the control circuit 30 may of course be provided outside the first housing, as well, to which the present application is not limited in particular.

In some embodiments, referring to fig. 6a, the phase processor 221 and the polarizer 222 are separated by a first gap, and the polarizer 222 and the liquid crystal phase processor 223 are separated by a second gap; or, referring to fig. 6b, the phase processor 221 and the polarizer 222 are attached together, and a second gap is formed between the polarizer 222 and the liquid crystal phase processor 223; alternatively, referring to fig. 6c, the phase processor 221 and the polarizer 222 are separated by a first gap, and the polarizer 222 and the liquid crystal phase processor 223 are bonded together. It can be understood that when the phase processor 221, the polarizer 222 and the liquid crystal retarder 223 are attached together, the polarizer 222 absorbs heat to raise the temperature of the phase processor, thereby affecting the phase retardation of the phase processor 221, lowering the transmittance of the polarizer 222, further absorbing more and raising the temperature, and thus forming a vicious circle until balance. Meanwhile, the polarizer 222 absorbs heat to raise the temperature of the liquid crystal phase processor 223, resulting in a reduced stereoscopic contrast and serious ghosting. In the present embodiment, the low transmittance and the serious ghost caused by heat dissipation can be solved by arranging the phase processor 221, the polarizer 222 and the liquid crystal phase retarder 223 separately to increase the heat dissipation area.

In some embodiments, referring to fig. 7a and 7b, a phase processor 221 may be embedded in the second housing 111 of the lens assembly 11, integrating the polarizer 222 and the liquid crystal phase retarder 223 remaining in the light valve. Alternatively, referring to fig. 7c, the phase processor 221 and the polarizer 222, which are attached to each other, may be embedded together in the second housing 111 of the lens assembly 11. The AR glass of the lens end face can be reduced in design.

Alternatively, the light valve 22 shown in fig. 6a, 6b and 6c may of course not be embedded in the lens assembly 11, but rather be formed separately as one piece.

In some embodiments, the phase processor is formed as an active device, and the system may further include: the temperature monitoring equipment is used for monitoring the temperature inside the polarization three-dimensional conversion equipment; and the driving device is used for adjusting the working parameters of the phase processor according to the temperature driving voltage acquired by the temperature monitoring equipment. In practical use, the light valve 22 is applied to projectors with different brightness and different projection ratios, and the different optical power densities on the light valve lead to different temperatures on the liquid crystal, and different environmental temperatures with different application scenes are added, so that in different application scenes, the temperature on the liquid crystal is high or low, even different by 10 to 20 ℃, and when the temperature is different, the phase processor (namely, a quarter wave plate) is not an accurate 1/4 wave plate, thereby leading to reduced contrast and serious ghost. Therefore, the temperature monitoring device can be used for monitoring the internal temperature and adjusting the working parameters of the phase processor according to the acquired temperature driving voltage so as to restore the accurate function.

Dual or multi-machine stereoscopic projection system

In some embodiments, the stereoscopic projection system may also be a dual or multi-machine stereoscopic projection system comprising two or more of the projection assemblies, wherein the projectors of the two or more of the projection assemblies are electrically connected, and the partially polarized light emitted by the projectors of the two or more of the projection assemblies, after passing through the respective light valves, forms the left-handed circularly polarized light and the right-handed circularly polarized light, respectively.

Referring to fig. 8, a dual stereoscopic projection system is shown, wherein the number of projection assemblies is two, and the electrical connection between the projectors 10 of the two projection assemblies can be understood as two single-path 3D projection assemblies, unlike the above-described embodiments. The light valve of the polarization stereoscopic conversion device 20 may include a phase processor, a linear polarizer, and a passive phase retarder. The difference between the present embodiment and the embodiment in which the stereoscopic projection system is a stand-alone stereoscopic projection system is that the phase retarder in the light valve of the foregoing embodiment is a liquid crystal active phase retarder, and the phase retarder in the light valve of the present embodiment is a passive phase retarder, but the polarization directions of the light modulated by the two are both left-handed or right-handed circularly polarized light.

The light beams of the projectors 10 of the two groups of the projection assemblies respectively output left circularly polarized light and right circularly polarized light after passing through the respective light valves. It will be appreciated that the two beam images of the two projectors 10 can be superimposed on the screen 90. In the 3D projection, the light beams from the light-emitting lenses 112 of the two projectors 10 form left circularly polarized light and right circularly polarized light through the 3D light valves, respectively, and the two polarized light beams are combined into a 3D image in the human brain through the metal screen 90 and the 3D glasses 80.

Although the present application has been described in terms of the preferred embodiments, it is not intended to be limited to the embodiments, and any person skilled in the art can make any possible variations and modifications to the technical solution of the present application by using the methods and technical matters disclosed above without departing from the spirit and scope of the present application, so any simple modifications, equivalent variations and modifications to the embodiments described above according to the technical matters of the present application are within the scope of the technical matters of the present application.

Claims

1. A stereoscopic projection system for 2D projection and 3D projection comprising at least one projection assembly, the projection assembly comprising:

the projector comprises a lens assembly, wherein the lens assembly comprises a second shell and a light-emitting lens arranged in the second shell and used for emitting partial polarized light, and the polarization degree of the partial polarized light is more than 75%;

the polarization three-dimensional conversion equipment comprises a first shell and a light valve arranged in the first shell, wherein a sealing space is formed between the light valve and the light-emitting lens, and the second shell is fixedly and hermetically connected with the first shell of the polarization three-dimensional conversion equipment;

the light valve is a single-light path light valve, wherein the light valve and the lens component are arranged side by side, so that the partial polarized light emitted by the projector passes through the light valve, and the light valve comprises: the polarization direction formed by the partial polarized light after passing through the phase processor is the same as the transmission axis of the polaroid;

and the control circuit is used for generating a driving signal matched with the film state of the projector to drive the light valve to work, and controlling the light valve to sequentially output left-handed circularly polarized light and right-handed circularly polarized light according to frame sequences when the projector performs 3D projection.

2. The stereoscopic projection system of claim 1, wherein the stereoscopic projection system comprises a single one of the projection assemblies, the system further comprising:

and the control circuit is electrically connected with the projector and the polarization three-dimensional conversion equipment.

3. The stereoscopic projection system of claim 1 comprising two or more of the projection assemblies, wherein the projectors of the two or more of the projection assemblies are electrically connected and the partially polarized light emitted by the projectors of the two or more of the projection assemblies, after passing through the respective corresponding light valves, forms the left circularly polarized light and the right circularly polarized light, respectively.

4. A stereoscopic projection system according to claim 2 or 3, wherein the partially polarized light emitted by the projector passes through the phase processor, the polarizer and the liquid crystal phase processor in that order.

5. The stereoscopic projection system of claim 4 wherein the polarizer is a reflective polarizer.

6. The stereoscopic projection system of claim 1, wherein the first housing is removably fixedly coupled to the projector.

7. The stereoscopic projection system of claim 1 wherein the light valve is rotatably mounted to an end of the lens assembly, the light valve being self-rotatably adjusted according to the polarization state of the partially polarized light and the rotational symmetry characteristics of the light valve to cover the current spot range of the partially polarized light emitted by the projector.

8. The stereoscopic projection system of claim 7 wherein the light valve does not cover at a single instant all of the spot range of the partially polarized light emitted by the projector, the all of the spot ranges being the sum of the current spot ranges corresponding to each instant.

9. The stereoscopic projection system of claim 1 wherein a minimum distance between the light valve and the lens assembly is determined based on a size of the light valve and a maximum optical energy density of the light valve.

10. The stereoscopic projection system of claim 1, wherein the size of the light valve is smaller than the size of the light extraction lens.

11. The stereoscopic projection system of claim 2, wherein the control circuit is integrated within the first housing and integrally mounted with the light valve.

12. The stereoscopic projection system of claim 4 wherein the phase processor is separated from the polarizer by a first gap and the polarizer is separated from the liquid crystal phase processor by a second gap; or the phase processor and the polaroid are attached together, and a second gap is reserved between the polaroid and the liquid crystal phase processor; or, a first gap is formed between the phase processor and the polaroid, and the polaroid and the liquid crystal phase processor are attached together.

13. The stereoscopic projection system of claim 12 wherein,

the phase processor, the polaroid and the liquid crystal phase processor in the light valve are independently arranged in a single-light-path light valve outside the lens component; or, the phase processor is embedded in the second housing of the lens assembly; or, the phase processor and the polaroid attached to the phase processor are embedded in the second housing of the lens assembly.

14. The stereoscopic projection system of claim 4 wherein the phase processor is formed as an active device, the system further comprising: