CN107976820A - Polarization modulating arrangement, method and the stereoscopic image showing system of stereoprojection light - Google Patents

Abstract

The present invention is applicable to the technical field of projection display, and provides a polarization modulation device for stereoscopic projection light, including: a polarization beam splitting component, which is used to split a projection beam carrying image information into two transmitted beams and two reflected beams , wherein the polarization states of the two transmitted light beams are different, and the polarization states of the two reflected light beams are also different; the first optical path direction adjustment component is used to adjust the propagation direction of the first reflected light beam; the second optical path direction adjustment component is used to adjust the second optical path direction adjustment component. The propagation direction of the reflected light beam; the polarization state conversion component is used to modulate the polarization state of part or all of the two transmitted light beams and the two reflected light beams, and the two transmitted light beams and the two reflected light beams have the same polarization state after modulation. Compared with the polarization splitting method with two optical paths, the present invention can effectively reduce the optical path difference between the reflected light beam and the transmitted light beam, so that the volume of the whole device is greatly reduced.

Description

Stereoscopic projection light polarization modulation device, method and stereoscopic image projection system

technical field

The invention belongs to the technical field of projection display, and in particular relates to a polarization modulation device and method for stereoscopic projection light and a stereoscopic image projection system.

Background technique

The principle of stereoscopic video viewing is that the left and right eyes of a person respectively receive the video images of the left and right eyes played in frame order, and then synthesize the video images of the left and right eyes through the brain to produce a stereoscopic effect.

The current left and right eye image receiving technologies mainly include the left and right polarization splitting methods, the left and right shutter switch synchronization methods, and the left and right red and blue splitting methods, among which the left and right polarization splitting methods are more widely used. In the left and right polarization splitting methods, single optical path polarization splitting technology and dual optical path polarization splitting technology have been produced successively according to the technological development track.

A typical principle of single-path polarization splitting is shown in Figure 1. The projector 11 sequentially projects a projection beam carrying an image for the left eye and a projection beam carrying an image for the right eye in sequence of frames, and the projection beams are separated by a polarizer 12. Polarized and converted into linearly polarized light, then the polarization modulator 13 modulates the left-handed circularly polarized light and the right-handed circularly polarized light according to the frame sequence, and projects it to the screen 15, and the left and right eyes of the audience receive it through the circularly polarized glasses 16 worn respectively. The left-handed circularly polarized light and the right-handed circularly polarized light reflected by the curtain 15, wherein the synchronization circuit 14 is used to control the synchronous operation of the projector 11 and the polarization modulator 13. However, because the polarizer 12 is an absorption type, only part of the light energy is polarized and another part of the light energy is discarded during the polarizing process, so that a large amount of light energy is converted into heat on the polarizer 12. When using high-brightness film When the projector is used, the temperature of the polarizer 12 will rise rapidly, so that the aging speed of the polarizer 12 is accelerated, and the optical performance is obviously deteriorated. In serious cases, the strong light beam will burn the polarizer 12 . Therefore, the single optical path polarization splitting was later replaced by the dual optical path polarization splitting.

The principle of the dual optical path polarization beam splitting method is shown in Figure 2. It is mainly realized based on a slanted plate type beam splitting prism. The beam splitting prism has a polarizing beam splitting film 2 arranged obliquely. P-polarized light and reflected S-polarized light, and then convert P-polarized light to S-polarized light or convert S-polarized light to P-polarized light, and finally modulate the two beams of light into left-handed circularly polarized light or Right-handed circularly polarized light. Since the projection light is fully utilized in the polarization process, the utilization rate of the projection light and the brightness of the projection picture are also improved.

However, the size of the modulation system using dual optical path polarization splitting will be large, and the required optical devices will also be large, and there are many difficulties in device processing and assembly.

Contents of the invention

The technical problem to be solved by the embodiments of the present invention is the large volume of the existing stereoscopic projection polarization modulation device based on the dual optical path polarization splitting technology, and aims to provide a new and smaller stereoscopic projection polarization modulation device.

In order to solve the above-mentioned technical problems, the embodiment of the present invention is implemented in the following way, a polarization modulation device for stereoscopic projection light, comprising:

A polarization beam splitting component, configured to split the projection beam carrying image information into a first transmitted beam with a first polarization state, a second transmitted beam with a second polarization state, and a first reflected beam with a second polarization state and a second reflected light beam having a first polarization state; wherein, the split first transmitted light beam and the second transmitted light beam propagate toward the direction of the imaging surface, and the first transmitted light beam and the first reflected light beam The imaging positions on the imaging surface are the same, and the imaging positions of the second transmitted light beam and the second reflected light beam are the same on the imaging surface;

a first optical path direction adjusting component, configured to adjust the propagation direction of the first reflected light beam, so that the first reflected light beam propagates toward the direction where the imaging surface is located;

a second optical path direction adjusting component, configured to adjust the propagation direction of the second reflected light beam, so that the second reflected light beam propagates toward the direction where the imaging surface is located;

a polarization state modulation component, configured to perform polarization state modulation on part or all of the first transmitted light beam, the second transmitted light beam, the first reflected light beam, and the second reflected light beam, so that the first A transmitted beam, the second transmitted beam, the first reflected beam and the second reflected beam have the same polarization state.

The embodiment of the present invention also provides a stereoscopic image projection system, comprising:

a projector, configured to sequentially project a projection beam carrying left-eye image information and a projection beam carrying right-eye image information in frame order;

A polarization modulation device for stereoscopic projection light as described above;

The curtain is used for imaging the projection light beams with the same polarization state modulated by the polarization modulation device of the stereoscopic projection light, and reflecting the formed images to the 3D glasses worn by the user.

An embodiment of the present invention also provides a method for polarization modulation of stereoscopic projection light, the method comprising the following steps:

Splitting the projection beam carrying image information into a first transmitted beam with a first polarization state, a second transmitted beam with a second polarization state, a first reflected beam with a second polarization state, and a first beam with a first polarization state The second reflected light beam; wherein, the split first transmitted light beam and the second transmitted light beam propagate toward the direction of the imaging surface, and the imaging positions of the first transmitted light beam and the first reflected light beam on the imaging surface Same, the imaging positions of the second transmitted light beam and the second reflected light beam on the imaging surface are the same;

adjusting the propagation direction of the first reflected light beam and the second reflected light beam, so that the first reflected light beam and the second reflected light beam propagate toward the direction where the imaging surface is located;

Polarization modulation is performed on part or all of the first transmitted beam, the second transmitted beam, the first reflected beam, and the second reflected beam, so that the first transmitted beam, the second transmitted beam, the first reflected beam, and the second reflected beam have the same polarization state.

Compared with the prior art, the embodiment of the present invention has the beneficial effect that: the stereoscopic light projection polarization modulation device provided by the embodiment of the present invention uses a polarization splitting component to divide the projection beam into four beams of light including two transmissions and two reflections, wherein The polarization states of the two transmitted light beams are different, and the polarization states of the two reflected light beams are also different. Since the light beam corresponding to a complete image frame is divided into two reflected light beams during polarization, there is a dual optical path with one transmitted light beam and one reflected light beam. Compared with the polarization splitting method, the embodiment of the present invention effectively reduces the optical path difference between the reflected beam and the transmitted beam, so that the subsequent optical path direction adjustment component and optical path compensation component can be selected to be smaller in size, thereby greatly reducing the volume of the entire device.

Description of drawings

Fig. 1 is the schematic diagram of the principle that the stereoscopic image projection system provided by the prior art adopts single optical path polarization splitting;

Fig. 2 is a schematic diagram of the principle of dual optical path polarization splitting used in the stereoscopic image projection system provided by the prior art;

Fig. 3 is a structural principle diagram of the polarization modulation device for stereoscopic projection light provided by the first embodiment of the present invention;

Fig. 4 is a structural principle diagram of a polarization modulation device for stereoscopic projection light provided by the second embodiment of the present invention;

Fig. 5 is a structural principle diagram of a polarization beam splitting component in the form of a prism group structure provided by the second embodiment of the present invention;

6A and 6B are schematic diagrams of the wire grid structure of the polarization splitting layer on the first substrate provided by the second embodiment of the present invention;

7A and 7B are schematic diagrams of the wire grid structure of the polarization splitting layer on the second substrate provided by the second embodiment of the present invention;

Figure 8 and Figure 9 are schematic diagrams of the wire grid structure of two polarization beam splitting layers in the polarization beam splitting component in the form of a prism group structure provided by the second embodiment of the present invention;

Fig. 10 is a schematic diagram of an optical path in which two transmitted beams exist in a mixed polarization region according to the second embodiment of the present invention;

Fig. 11 is a structural principle diagram of a polarization modulation device for stereoscopic projection light provided by the third embodiment of the present invention;

Fig. 12 is a structural principle diagram of a polarization beam splitting component in the form of a prism group structure provided by the third embodiment of the present invention;

Fig. 13 is a structural principle diagram of a polarization modulation device for stereoscopic projection light provided by the fourth embodiment of the present invention;

Fig. 14 is a structural principle diagram of a polarization beam splitting component in the form of a prism group structure provided by the fourth embodiment of the present invention;

Fig. 15 is a schematic diagram of an optical path in which two transmitted beams exist in a mixed polarization region according to the fourth embodiment of the present invention;

Fig. 16 is a structural principle diagram of a polarization beam splitting component in the form of a prism group structure provided by the fifth embodiment of the present invention;

Fig. 17 is a structural principle diagram of a polarization beam splitting assembly in the form of a prism group structure provided by the fifth embodiment of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Different from the traditional idea of dividing the projected beam into a transmitted beam and a reflected beam in the dual optical path polarization splitting method, the embodiment of the present invention divides the projected beam into four beams including two transmitted beams and two reflected beams.

Based on this principle, as shown in Figure 3, the first embodiment of the present invention provides a polarization modulation device for stereoscopic projection light, including: a polarization beam splitting component 31, a first optical path direction adjustment component 32, a second optical path direction adjustment component 33 and polarization state modulation component 34, the function of each component is introduced as follows:

Polarization beam splitting component 31----used to split the projection beam carrying image information into a first transmitted beam with a first polarization state, a second transmitted beam with a second polarization state, and a second transmitted beam with a second polarization state A first reflected beam of and a second reflected beam having a first polarization state.

The polarization modulation device 31 for stereoscopic projection light provided by the embodiment of the present invention is placed between the projector and the imaging surface (i.e., the screen) during use, and is used to optically act on the projection beam projected by the projector, so that the projection beam Before projecting onto the imaging surface, it has a uniform polarization state such as linear polarization or circular polarization. The imaging surface then reflects the projection beam with the polarization state to the 3D glasses worn by the audience. In the process of reflecting the projection beam, the polarization state of the projection beam cannot be changed, which is usually realized by a metal screen.

First, the projector alternately projects the projection beam carrying the image information of the left eye and the projection beam carrying the image information of the right eye. For the projection beam, the projection beam carrying the image information of the right eye is projected at time T2, the projection beam carrying image information of the left eye is projected at time T3, the projection beam carrying image information of the right eye is projected again at time T4, and so on. In terms of hardware, the projector is required to support video playback with a frame frequency of 100HZ or higher, and digital micromirror projectors, liquid crystal on silicon projectors, etc. can be used.

Then, the projection beam is polarized and split by the polarization beam splitting component 31. In the embodiment of the present invention, the polarization beam splitting component 31 divides the projection beam into four beams, namely, the first transmitted beam, the first reflected beam, and the second transmitted beam. beam, the second reflected beam. Wherein, the image information carried by the first transmitted light beam and the first reflected light beam are the same, and the imaging position on the imaging surface is the same; The imaging position is the same.

The split first transmitted beam has a first polarization state, the first reflected beam has a second polarization state, the second transmitted beam has a second polarization state, and the second reflected beam has a first polarization state, wherein the first transmitted beam And the second transmitted light beam directly propagates to the direction where the imaging surface is located, while the first reflected light beam is reflected and causes the propagation direction to be perpendicular to the corresponding first transmitted light beam. Similarly, the second reflected light beam is caused by being reflected The propagation direction will be perpendicular to the propagation direction of the corresponding second transmitted light beam, so it is necessary to adjust the propagation direction of the first reflected light beam and the second reflected light beam so that the first reflected light beam and the second reflected light beam can move toward the direction of the imaging surface spread.

It should be emphasized that since both the first transmitted light beam and the second transmitted light beam propagate directly to the direction of the imaging surface after splitting, they look like a whole beam of light macroscopically, but due to the different polarization states of the two , in essence, it should be understood that these are two different beams. In addition, FIG. 3 only schematically shows the propagation paths of the first transmitted light beam and the second transmitted light beam. In fact, since the projected light beam projected by the projector is divergent, the projected light beam is split by the polarization beam splitting component 31. The first transmitted light beam and the second transmitted light beam obtained after the beam are still divergent, so that the imaging areas of the first transmitted light beam and the second transmitted light beam will partially overlap on the imaging surface.

The above-mentioned first polarization state and second polarization state are both linearly polarized and the polarization directions of the two are orthogonal, for example, one is P-polarized light and the other is S-polarized light. Specifically, the first polarization state can be P-polarized light, and the second polarization state can be The two polarization states are S-polarized light, or the first polarization state is S-polarized light, and the second polarization state is P-polarized light.

The polarizing beam splitting component 31 can use a polarizing beam splitting film for beam splitting and polarizing, can also use an optical wire grid for beam splitting and polarizing, or use a polarizing beam splitting film and an optical wire grid structure for beam splitting and polarizing, for example, use a polarizing beam splitting The film splits the first transmitted light beam and the first reflected light beam, and adopts the optical wire grid structure to split the second transmitted light beam and the second reflected light beam.

The first optical path direction adjusting component 32 is used to adjust the propagation direction of the first reflected light beam, so that the first reflected light beam propagates toward the direction of the imaging surface.

The adjustment direction of the first optical path direction adjustment assembly 32 can make the final imaging position of the first reflected light beam on the imaging surface overlap with the imaging position of the first transmitted light beam. During specific implementation, the adjustment direction of the first optical path direction adjustment assembly 32 can be set To be adjustable, in order to adjust the imaging position of the first reflected beam on the imaging surface, it can usually be realized by devices with reflective functions such as plane mirrors and curved mirrors that can expand or reduce the size of the beam. Of course, lenses and the like can also be used. Realization of optical devices that change the direction of the light path.

The second optical path direction adjusting component 33 is used to adjust the propagation direction of the second reflected light beam, so that the second reflected light beam propagates toward the direction of the imaging surface.

Similarly, the adjustment direction of the second optical path direction adjustment assembly 33 can make the final imaging position of the second reflected light beam on the imaging surface overlap with the imaging position of the second transmitted light beam. During specific implementation, the adjustment of the second optical path direction adjustment assembly can be The direction is set to be adjustable, so as to facilitate adjustment of the imaging position of the second reflected light beam 33 on the imaging surface. Usually, it can be realized by using a device with reflection function such as a plane mirror or a curved mirror that can expand or reduce the size of the beam. Of course, it can also be realized by using Lenses and other optical devices that change the direction of the light path are realized.

Polarization modulation component 34----is used to modulate the polarization state of part or all of the first transmitted light beam, the second transmitted light beam, the first reflected light beam and the second reflected light beam, so that the first transmitted light beam, the second reflected light beam The two transmitted beams, the first reflected beam and the second reflected beam have the same polarization state.

The polarization state modulation component 34 sequentially modulates the four beams of light into a polarization state that can only be received by the left eye and a polarization state that can only be received by the right eye according to the frame sequence. For example, in the current frame, the four beams of light are modulated to be received by The polarization state received by the left eye but not received by the right eye is modulated in the next frame to the polarization state which cannot be received by the left eye but can be received by the right eye.

However, in any frame, the polarization states of the four light beams need to be modulated to be consistent before reaching the imaging surface. During the specific modulation, only the polarization states of part of the light beams can be modulated. For example, whether the image corresponding to the left-eye image is played frame or the image frame corresponding to the right-eye image, the polarization state modulation component 34 only converts the polarization state of the first transmitted light beam and the second reflected light beam from the first polarization state to the second polarization state, so that the four beams all have the second polarization state. The polarization state, or the polarization state modulation component 34 only converts the polarization state of the second transmitted light beam and the first reflected light beam from the second polarization state to the first polarization state, so that the four beams all have the first polarization state; it can also be All four beams of light participate in the polarization state modulation process. For example, when playing the image frame corresponding to the left-eye image, the polarization state modulation component 34 converts the polarization state of the first transmitted light beam and the second reflected light beam from the first polarization state to the second polarization state. Two polarization states, so that the four beams of light all have the second polarization state, and when playing the image frame corresponding to the right-eye image, the polarization state modulation component 34 changes the polarization state of the second transmitted light beam and the first reflected light beam from the second polarization state converted to the first polarization state, so that the four beams all have the first polarization state.

As mentioned above, the polarization states of the four beams split by the above-mentioned polarization beam splitting component 31 are linear P polarization or S polarization. Then, if the audience wears linear polarized glasses, the polarization modulation component only needs to change It is sufficient to modulate the four beams of light into all P-polarized or modulated to S-polarized in one frame, but if the audience wears circularly polarized glasses, further modulation is required to be left-handed circularly polarized light and right-handed circularly polarized light. When it needs to be modulated into circularly polarized light, the polarization state modulation component 34 needs to include: a polarization state conversion unit and a light modulator.

Among them, the polarization conversion unit needs to modulate the four beams of light to have a unified linear polarization state in each frame. Based on the above-mentioned principles, the polarization conversion unit has two working modes:

Mode 1: The polarization state conversion unit is used to convert the polarization state of the first transmitted light beam and the second reflected light beam from the first polarization state to the second polarization state, so that the first transmitted light beam, the second transmitted light beam, and the first reflected light beam and the second reflected light beam are both in the second polarization state; or, for converting the polarization state of the second transmitted light beam and the first reflected light beam from the second polarization state to the first polarization state, so that the first transmitted light beam , the second transmitted light beam, the first reflected light beam and the second reflected light beam are all in the first polarization state.

Mode 2: the polarization state conversion unit is used to convert the polarization state of the first transmitted beam and the second reflected beam from the first polarization state to the second polarization state when playing the image frame corresponding to the left-eye image, so that the four beams has a second polarization state, and when playing the image frame corresponding to the right eye image, the polarization state of the second transmitted light beam and the first reflected light beam is converted from the second polarization state to the first polarization state, so that the four beams all have the first polarization state A state of polarization.

Then, the first transmitted light beam, the second transmitted light beam, the first reflected light beam and the second reflected light beam uniformly having the first polarization state or the second polarization state are modulated into left-handed circularly polarized light and right-handed circularly polarized light by the light modulator in frame sequence. circularly polarized light.

Among them, when the polarization conversion unit works in the above-mentioned mode 1, it can be implemented by using a half-wave plate, which can convert P-polarized light into S-polarized light or S-polarized light into P-polarized light. Of course, other optional Devices that rotate the linear polarization state by 90 degrees are realized, such as TN liquid crystal cells, etc. When the polarization conversion unit works in the above-mentioned mode 2, it can be implemented by selecting a device that can rotate the polarization state by 90 degrees in the optical path of each beam, such as a TN liquid crystal cell, etc., and only needs to control the TN corresponding to the four beams. For the operation of the liquid crystal cell, each frame of image needs to control two of the TN liquid crystal cells to rotate the polarization direction of the linearly polarized light by 90 degrees, while the other two are in a non-rotational working state.

The above-mentioned optical modulator can be realized by using a device with a quarter-wave delay function, such as a liquid crystal device or a quarter-wave plate, which can share one optical modulator for four beams of light, or can be separated on the four beams of light. Set up a light modulator.

To sum up, in the first embodiment, since the projection beam corresponding to a complete image frame is divided into two reflected beams by the polarization beam splitting component 31 during polarization, the optical path between the reflected beam and the transmitted beam is effectively reduced difference, so that the subsequent optical path direction adjustment components and optical path compensation components can be selected to be smaller in size, so that the volume of the entire device is greatly reduced.

The structure and position of the polarization beam splitting component 31 and the polarization conversion unit in the first embodiment of the present invention can be designed in various ways, as long as the above optical functions can be satisfied. Several embodiments are listed below for explanation and description. It should be understood that during specific implementation, those skilled in the art can flexibly change other various implementations based on the present invention as needed.

FIG. 4 shows a polarization modulation device for stereoscopic projection light according to a second embodiment of the present invention. This embodiment is suitable for the situation where the audience wears circular polarizing glasses.

In this embodiment, the first polarization state and the second polarization state of the beam split by the polarization beam splitting component are both linearly polarized, and the polarization directions of the two are orthogonal, for example, the first polarization state and the second polarization state are respectively For linear P polarization and S polarization. The polarizing beam splitting component includes a first substrate 3111 and a second substrate 3112, the two substrates are connected to each other in a V shape, and a ridge A1 is formed at the connected position, and the protruding direction of the ridge A1 is opposite to the propagation direction of the projected beam. That is, the protruding direction of the ridge A1 is toward the direction where the projector is located. In specific use, it is preferable to place the ridge A1 on the center line of the projection beam. Both the first substrate 3111 and the second substrate 3112 are provided with a polarization splitting layer, and the polarization splitting layer of the first substrate 3111 can transmit the first transmitted beam and reflect the first reflected beam, and the polarization splitting layer of the second substrate 3112 can The second transmitted light beam is transmitted and the second reflected light beam is reflected. In Figure 4, "●" indicates that the beam is in a linearly polarized state and the polarization direction is perpendicular to the paper, Indicates that the beam is linearly polarized and the polarization direction is parallel to the paper, and "○" indicates that the beam is circularly polarized.

As a variation structure of the second embodiment, the polarization beam splitting component can also be designed as a structure of a polarization beam splitting prism group. As shown in Figure 5, the polarization beam splitting prism group is formed by bonding three isosceles right-angle prisms of at least the first prism 3121, the second prism 3122 and the third prism 3123. After bonding, the whole is a rectangular parallelepiped structure. Made of transparent substrate. The two right-angle sides of the third prism 3123 are attached to the hypotenuse of the first prism 3121 and the hypotenuse of the second prism 3122 respectively, and the joints respectively have a first polarization splitting layer 3124 and a second polarization splitting layer 3125, the first The polarizing beam splitting layer 3124 and the second polarizing beam splitting layer 3125 are vertical and connected to each other in a V-shape. A ridge A2 is formed at the connected position. The polarization splitting layer 3124 can transmit the first transmitted beam and reflect the first reflected beam, and the second polarization splitting layer 3125 can transmit the second transmitted beam and reflect the second reflected beam. In the above-mentioned polarization beam splitter prism group, the surface where the ridge A2 is located is the incident surface of the projected light beam. In specific use, it is best to place the ridge A2 on the centerline of the projected light beam.

Please refer to FIG. 4 again, the function of the first optical path direction adjustment assembly 321 in this embodiment is the same as that of the first optical path direction adjustment assembly 32 in the first embodiment, and the second optical path direction adjustment assembly 331 in this embodiment The function of is the same as that of the first optical path direction adjusting component 33 in the first embodiment, and details are not repeated here. The polarization state modulation component includes: a first polarization state converter 3411 , a second polarization state converter 3412 and a light modulator 3413 . Wherein, the first polarization state converter 3411 is located on the optical path where the first reflected light beam is located, and is used to convert the polarization state of the first reflected light beam from the second polarization state to the first polarization state; the second polarization state converter 3412 is located on the second polarization state The optical path where the two transmitted beams are located is used to convert the polarization state of the second transmitted beam from the second polarization state to the first polarization state. It should be understood that the first polarization state converter 3411 and the second polarization state converter 3412 can also be placed on the optical path where the other two light beams are located during specific implementation, for example, the first polarization state converter 3411 is placed on the second reflected light beam on the optical path where the polarization state of the second reflected light beam is converted from the first polarization state to the second polarization state; The polarization state of a transmitted light beam is switched from the first polarization state to the second polarization state.

After the first polarization state converter 3411 and the second polarization state converter 3412 respectively adjust the polarization states of the light beams to be consistent, the light modulator 3413 will uniformly have the first polarization state or the second polarization state. The light beam, the second transmitted light beam, the first reflected light beam and the second reflected light beam are sequentially modulated into left-handed circularly polarized light and right-handed circularly polarized light, for example, in the current frame, the light modulator 3413 adjusts each light beam to be left-handed circularly polarized light so that the left lens of the circularly polarized glasses worn by the audience can pass through the left-handed circularly polarized light, while the right lens cannot pass through the left-handed circularly polarized light; Circularly polarized light, so that the right lens of the circularly polarized glasses worn by the audience can pass through the right-handed circularly polarized light, while the left lens cannot pass through the right-handed circularly polarized light.

Wherein, the first polarization state converter 3411 and the second polarization state converter 3412 can be implemented with half-wave plates, which can convert P-polarized light into S-polarized light or S-polarized light into P-polarized light. A TN liquid crystal cell that can rotate the linear polarization state by 90 degrees is selected. The above-mentioned optical modulator can be realized by using a device with a quarter-wave delay function, such as a liquid crystal device or a quarter-wave plate, which can share one optical modulator for four beams of light, or can be separated on the four beams of light. Set up a light modulator.

In the second embodiment, whether it is the polarization beam splitting layer on the plate-shaped polarization beam splitting assembly or the polarization beam splitting layer on the polarization beam splitting assembly with a prism group structure, a wire grid structure is used to realize polarization splitting, wherein the beam splitting The wire grid arrangement directions of the wire grid parts that emit the first transmitted light beam and the first reflected light beam are orthogonal to the wire grid arrangement directions of the wire grid parts that split the second transmitted light beam and the second reflected light beam.

Specifically, for the polarization beam splitting layer on the plate-shaped polarization beam splitting component, Figure 6A and Figure 6B are the wire grid structure on the polarization beam splitting layer on the first substrate 3111, wherein Figure 6A is a plan view of the wire grid structure, and Figure 6B is Schematic diagram of the cross-section of the wire grid structure, "●" indicates that the direction of the wire grid is perpendicular to the paper. 7A and 7B are the wire grid structure on the polarization splitting layer on the second substrate 3112, wherein FIG. 7A is a plan view of the wire grid structure, and FIG. 7B is a schematic cross-sectional view of the wire grid structure, Indicates that the direction of the wire grid is parallel to the paper. It can be seen that the arrangement direction of the wire grids in the polarization beam splitting layer of the first substrate 3111 is perpendicular to the arrangement direction of the wire grids in the polarization beam splitting layer of the second substrate 3112 .

As for the polarization beam splitting layer on the polarization beam splitting component adopting the prism group structure, Fig. 8 and Fig. 9 respectively show the wire grid structure on the first polarization beam splitting layer 3124 and the wire grid structure on the second polarization beam splitting layer 3125, It can be seen that the wire grids in FIG. 8 are arranged along the vertical direction. When the unpolarized projected light beam R _Randomly is incident on the wire grid structure on the first polarization splitting layer 3124, the transmitted S linearly polarized light R can be split into beams. _s and the reflected P linearly polarized light R _p ; while the wire grids in Fig. 9 are arranged along the horizontal direction, when the unpolarized projected light beam R _Randomly enters the wire grid structure on the second polarization splitting layer 3125, the beam can be split out Reflected S linearly polarized light R _s and transmitted P linearly polarized light R _p .

To sum up, in the second embodiment, the projected light beam corresponding to a complete image frame is divided into two reflected light beams by the polarization splitting layers on the two substrates during polarization, or is polarized by two polarized light beams inside the prism group. The splitting layer is divided into two reflected beams, effectively reducing the optical path difference between the reflected beam and the transmitted beam, so that the subsequent optical path direction adjustment components and optical path compensation components can be selected to be smaller in size, so that the volume of the entire device is greatly reduced, and, Compared with the double optical path slanted plate beam splitter, this "V" shaped polarization beam splitter can be made thinner and its thickness can be reduced by almost half.

Further, considering that the projection beam in the second embodiment is not strictly divided into two parts that do not intersect each other up and down when passing through the polarization beam splitting component, in fact, a part of the beam passing through the upper half of the polarization beam splitting component will run to Below, on the contrary, part of the light beam passing through the lower half of the polarization beam splitting component will also run to the top, so in the central area of the imaging surface, the light beams of the two polarization states are actually mixed together, as shown in Figure 10, where "dot-dash Line" indicates the upper half of the projected beam, and "long and short lines" indicate the lower part of the projected beam. It can be seen that after passing through the polarization beam splitting component, there will be a mixed area between the upper and lower parts of the projected beam , there are two kinds of polarization states of transmitted light in the mixing region, so that it will be difficult for the subsequent polarization state modulation component to adjust the polarization state consistency of the projected light beam in the mixing region. To solve this technical problem, the third embodiment of the present invention provides a polarization modulation device for stereoscopic projection light as shown in FIG. 11 . This embodiment is suitable for the situation where the audience wears circular polarizing glasses.

Please refer to FIG. 11 , the difference from the second embodiment is the position where the second polarization state converter 3412 is placed in this embodiment. In this embodiment, the second polarization state converter 3412 is attached to the second substrate 3112 to transmit On the surface of the second transmitted light beam, this is equivalent to converting the polarization state of the second transmitted light beam before the second transmitted light beam is mixed with the first transmitted light beam. In the mixing region shown in FIG. 10 The polarization states of the beams are already aligned. It should be understood that, in specific implementation, if the first polarization state converter 3411 is located on the optical path where the second reflected light beam is located, the second polarization state converter 3412 needs to be attached to the first substrate 3111 to transmit the first transmitted light. On the surface.

For the polarization beam splitting assembly in the form of a prism structure shown in the second embodiment, the second polarization state converter 3412 can be packaged in the polarization beam splitting prism group, and the second polarization splitting layer 3125 can transmit the second transmission One side of the beam, as shown in Figure 12. Of course, the second polarization state converter 3412 can also be packaged on the side of the first polarization splitting layer 3124 that can transmit the first transmitted light beam.

The rest of the third embodiment is the same as that of the second embodiment, and will not be repeated here.

To sum up, in the third embodiment, the projected light beam corresponding to a complete image frame is not only divided into two by the polarization beam splitter layers on the two substrates or by the two polarization beam splitter layers inside the prism group during polarization. reflected beam, and before the second transmitted beam is mixed with the first transmitted beam, the polarization state of the second transmitted light has been converted, therefore, effectively reducing the optical path difference between the reflected beam and the transmitted beam, making the whole device While the volume is greatly reduced, it is also more conducive to the modulation of the polarization states of the two transmitted beams by the subsequent polarization modulation component. Similarly, the polarization beam splitting component of the "V" structure in this embodiment and the slant plate type with dual optical paths Compared with the traditional beam splitting prism, it can also be made thinner, and the thickness is reduced by almost half.

FIG. 13 shows a polarization modulation device for stereoscopic projection light according to a fourth embodiment of the present invention. This embodiment is also applicable to the situation where the audience wears circular polarizing glasses.

Please refer to FIG. 13. In this embodiment, the first polarization state and the second polarization state of the beam split by the polarization beam splitting component are both linearly polarized, and the polarization directions of the two are orthogonal, for example, the first polarization state and the second polarization state The second polarization states are linear P polarization and S polarization, respectively. The polarizing beam splitting component includes a first substrate 3211 and a second substrate 3212, the two substrates are connected to each other in a V-shape, and a ridge B1 is formed at the connected position, and the protruding direction of the ridge B1 is the same as the propagation direction of the projection beam, that is, The protrusion direction of the ridge B1 coincides with the propagation direction of the projection beam. In specific use, it is preferable to place the ridge B1 on the centerline of the projection beam. Both the first substrate 3211 and the second substrate 3212 are provided with a polarization splitting layer, and the polarization splitting layer of the first substrate 3211 can transmit the first transmitted beam and reflect the first reflected beam, and the polarization splitting layer of the second substrate 3212 can The second transmitted light beam is transmitted and the second reflected light beam is reflected, wherein the first reflected light beam split by the polarization splitting layer of the first substrate 3211 can pass through the second substrate 3212 and then be directed by the second optical path direction adjustment component 332 adjusts the propagation direction to the direction of the imaging surface, the second reflected light beam split by the polarization splitting layer of the second substrate 3212 can pass through the first substrate 3211 and then the first optical path direction adjustment component 322 adjusts the propagation direction to The direction in which the imaging surface is located. In Figure 13, "●" indicates that the beam is in a linearly polarized state and the polarization direction is perpendicular to the paper, Indicates that the beam is linearly polarized and the polarization direction is parallel to the paper, and "○" indicates that the beam is circularly polarized.

As a variation structure of the fourth embodiment, the polarization beam splitting component can also be designed as a structure of a polarization beam splitting prism group. As shown in Figure 14, the polarization beam splitter prism group is formed by bonding three isosceles right-angle prisms of at least a first prism 3221, a second prism 3222 and a third prism 3223. After bonding, the whole is a rectangular parallelepiped structure. Made of transparent substrate. The two right-angle sides of the third prism 3223 are attached to the hypotenuse of the first prism 3221 and the hypotenuse of the second prism 3222 respectively, and the joints respectively have a first polarization splitting layer 3224 and a second polarization splitting layer 3225, the first The polarization splitting layer 3224 and the second polarization splitting layer 3225 are vertical and connected to each other in a V-shape, and a ridge B2 is formed at the connected position, and the protruding direction of the ridge B2 is consistent with the propagation direction of the projection beam, and the first polarization The light splitting layer 3224 can transmit the first transmitted light beam and reflect the first reflected light beam, and the second polarized light splitting layer 3225 can transmit the second transmitted light beam and reflect the second reflected light beam, wherein the beam split by the first polarized light splitting layer 3224 The first reflected light beam can pass through the second polarization splitting layer 3225, and then the second optical path direction adjustment component 332 can adjust the propagation direction to the direction of the imaging surface, and the second reflected light beam split by the second polarization splitting layer 3225 The propagation direction can be adjusted to the direction of the imaging surface by passing through the first polarization splitting layer 3224 and then adjusted by the first light path direction adjustment component 322 . In the above-mentioned polarization beam splitter prism group, the surface where the ridge B2 is located is the incident surface of the projected light beam. In specific use, it is preferable to place the ridge B2 on the center line of the projected light beam.

Please refer to FIG. 13 again, the function of the first optical path direction adjustment assembly 322 in this embodiment is the same as that of the first optical path direction adjustment assembly 32 in the first embodiment, and the second optical path direction adjustment assembly 332 in this embodiment The function of is the same as that of the first optical path direction adjusting component 33 in the first embodiment, and details are not repeated here. The polarization state modulation component includes: a polarization state converter 3421 and a light modulator 3422 . Wherein, the polarization state converter 3421 is located on the optical path where the first reflected light beam is located and the optical path where the second transmitted light beam is located at the same time, and is used to convert the polarization state of the first reflected light beam and the second transmitted light beam from the second polarization state to the second polarization state. A state of polarization. It should be understood that during specific implementation, the polarization state converter 3421 can also be set to be located on the optical path where the second reflected light beam is located and the optical path where the first transmitted light beam is located at the same time, so as to convert the polarization states of the second reflected light beam and the first transmitted light beam to Switch from the first polarization state to the second polarization state.

After the polarization state converter 3421 adjusts the polarization states of the light beams to be consistent, the light modulator 3422 uniformly transforms the first transmitted light beam, the second transmitted light beam, and the first reflected light beam with the first polarization state or the second polarization state and the second reflected light beam are modulated into left-handed circularly polarized light and right-handed circularly polarized light in frame order. The specific modulation principle of the light modulator 3422 is the same as that of the light adjuster 3413 in the second embodiment, and will not be repeated here.

Wherein, the polarization state converter 3421 can also be realized by using a device capable of rotating the linear polarization state by 90 degrees, such as a half-wave plate or a TN liquid crystal cell, and details are not repeated here.

Same as the second embodiment, the polarization splitting layer on the plate-shaped polarization beam splitting component in this embodiment, or the polarization splitting layer on the polarization beam splitting component with a prism group structure, all adopt a wire grid structure to realize polarization splitting, Wherein, each wire grid arrangement direction of the wire grid part that splits the first transmitted light beam and the first reflected light beam is opposite to each wire grid arrangement direction of the wire grid part that splits the second transmitted light beam and the second reflected light beam pay. For the specific wire grid structure, please refer to FIG. 6A , FIG. 6B , FIG. 7A , FIG. 7B , FIG. 8 and FIG. 9 , and details will not be repeated here.

To sum up, in the fourth embodiment, the projected light beam corresponding to a complete image frame is divided into two reflected light beams, which effectively reduces the optical path difference between the reflected light beam and the transmitted light beam, so that the subsequent optical path direction adjustment components, The optical path compensation component can be selected in a smaller size, so that the volume of the whole device is greatly reduced. Similarly, the polarization beam splitting component of the "V" shape structure in this embodiment can also be compared with the inclined plate beam splitting prism with two optical paths. Make it thinner and reduce the thickness by almost half.

Similar to the second embodiment, the fourth embodiment also has the situation that there are two kinds of polarization states of transmitted light in the mixing region of the two transmitted light beams, as shown in FIG. 15 . To solve this technical problem, the fifth embodiment of the present invention provides a polarization modulation device for stereoscopic projection light as shown in FIG. 16 . This embodiment is suitable for the situation where the audience wears circularly polarized glasses.

Please refer to FIG. 16 , the difference from the fourth embodiment is the position where the polarization state converter 3421 is placed. In this embodiment, the polarization state converter 3421 is attached to the second substrate 3212 to transmit the second transmitted light beam and the first reflected light beam. On the surface of , this is equivalent to converting the polarization state of the second transmitted light before the second transmitted light is mixed with the first transmitted light. The polarization state of the beam in the mixing region shown in Fig. 15 Already agreed. It should be understood that, during specific implementation, the polarization state converter 3421 may also be attached to the surface of the first substrate 3211 through which the first transmitted light beam and the second reflected light beam can be transmitted.

For the polarization beam-splitting component in the form of a prism structure shown in the fourth embodiment, in this embodiment, the polarization state converter 3421 can be packaged in the polarization beam-splitting prism group, and located in the second polarization beam-splitting layer 3225 that can transmit One side of the second transmitted beam and the first reflected beam, as shown in Figure 17. Of course, the polarization state converter 3421 can also be packaged on the side of the first polarization splitting layer 3224 that can transmit the first transmitted light beam and the second reflected light beam.

The remaining parts of the fifth embodiment are the same as those of the fourth embodiment, and will not be repeated here.

To sum up, in the fifth embodiment, the projected light beam corresponding to a complete image frame is not only divided into two by the polarization beam splitter layers on the two substrates or by the two polarization beam splitter layers inside the prism group during polarization. reflected beam, and before the second transmitted beam is mixed with the first transmitted beam, the polarization state of the second transmitted light has been converted, therefore, effectively reducing the optical path difference between the reflected beam and the transmitted beam, making the whole device While the volume is greatly reduced, it is also more conducive to the modulation of the polarization states of the two transmitted beams by the subsequent polarization modulation component. Similarly, the polarization beam splitting component of the "V" structure in this embodiment and the slant plate type with dual optical paths Compared with the traditional beam splitting prism, it can also be made thinner, and the thickness is reduced by almost half.

The sixth embodiment of the present invention also provides a stereoscopic image projection system, including a projector, a polarization modulation device and a curtain. Wherein, the projector is used to sequentially project the projection light beam carrying the left-eye image information and the projection light beam carrying the right-eye image information in frame order; the polarization modulation device can adopt the polarization modulation device provided in any of the above embodiments; and The curtain is used as an imaging surface for imaging the projection light beams with the same polarization state modulated by the stereoscopic projection light polarization modulation device, and reflects the formed images to the 3D glasses worn by the user.

The seventh embodiment of the present invention also provides a method for polarization modulation of stereoscopic projection light, said method comprising the following steps:

Step S1, splitting the projection beam carrying image information into a first transmitted beam with a first polarization state, a second transmitted beam with a second polarization state, a first reflected beam with a second polarization state, and a first transmitted beam with a first polarization state. A second reflected light beam in a polarization state; wherein, the split first transmitted light beam and the second transmitted light beam propagate toward the direction of the imaging surface, and the first reflected light beam and the second reflected light beam are finally on the imaging surface It can be spliced into a complete video picture.

Step S2, adjusting the propagation directions of the first reflected light beam and the second reflected light beam, so that the first reflected light beam and the second reflected light beam propagate toward the direction where the imaging surface is located.

Step S3, performing polarization state modulation on part or all of the first transmitted beam, the second transmitted beam, the first reflected beam, and the second reflected beam, so that the first transmitted beam, the second transmitted beam, the first reflected beam, the second The two reflected beams have the same polarization state.

For the specific implementation principles of the above steps, please refer to the content disclosed above, and will not repeat them one by one.

It should be noted that the above-mentioned embodiments can also be implemented by adding different functional components to achieve corresponding effects. For example, a polarizing device that acts as a filter can be set in the optical path of each beam, so that the polarization state of each beam is more accurate. Pure, it is also possible to set an optical path compensation component in the optical path of some beams, so that all beams have the same optical path when they reach the imaging surface.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention. Inside.

Claims (15)

1. A kind of 1. polarization modulating arrangement of stereoprojection light, it is characterised in that including：

   Polarization beam splitting assembly, the projected light beam beam splitting for will carry image information are the first transmission with the first polarization state Light beam, the second transmitted light beam with the second polarization state, the first the reflected beams with the second polarization state and with first polarization Second the reflected beams of state；Wherein, the first transmitted light beam and the second transmitted light beam gone out by beam splitting is to the side where imaging surface To propagation, and image space of first transmitted light beam with first the reflected beams on imaging surface is identical, and described Image space of two transmitted light beams with second the reflected beams on imaging surface is identical；

   First optical path direction adjusts component, for adjusting the direction of propagation of first the reflected beams so that first reflection Light beam is propagated to the direction where imaging surface；

   Second optical path direction adjusts component, for adjusting the direction of propagation of second the reflected beams so that second reflection Light beam is propagated to the direction where imaging surface；

   Polarization state modulation component, for first transmitted light beam, second transmitted light beam, first the reflected beams and Part or all of in second the reflected beams carries out polarization state modulation, so that first transmitted light beam, described second saturating Irradiating light beam, first the reflected beams and second the reflected beams have identical polarization state.
2. 2. the polarization modulating arrangement of stereoprojection light as claimed in claim 1, it is characterised in that first polarization state and Two polarization states are linear polarization and the polarization direction of the two is orthogonal；The polarization state modulation component includes：Polarization converted unit And optical modulator；

   The polarization converted unit, for by the polarization state of first transmitted light beam and second the reflected beams from first Polarization converted is the second polarization state, so that first transmitted light beam, second transmitted light beam, first the reflected beams It is the second polarization state with second the reflected beams；Alternatively, it is used for second transmitted light beam and first reflected light The polarization state of beam from the second polarization converted be the first polarization state so that first transmitted light beam, second transmitted light beam, First the reflected beams and second the reflected beams are the first polarization state；

   Alternatively, the polarization converted unit, for when playing the corresponding picture frame of left-eye images, by first transmitted light The polarization state of beam and second the reflected beams from the first polarization converted be the second polarization state so that first transmitted light Beam, second transmitted light beam, first the reflected beams and second the reflected beams are the second polarization state, and are being played During the corresponding picture frame of right-eye image, by the polarization state of second transmitted light beam and first the reflected beams from the second polarization State is converted to the first polarization state so that first transmitted light beam, second transmitted light beam, first the reflected beams and institute It is the first polarization state to state the second the reflected beams；

   The optical modulator, for unified the first transmitted light beam with the first polarization state or the second polarization state, second to be transmitted Light beam, the first the reflected beams and the second the reflected beams are modulated to left circularly polarized light and right-circularly polarized light according to frame sequential.
3. 3. the polarization modulating arrangement of stereoprojection light as claimed in claim 1, it is characterised in that first polarization state and Two polarization states are linear polarization and the polarization direction of the two is orthogonal；The polarization state modulation component includes：First polarization converted Device, the second polarization form converter and optical modulator；

   Wherein, first polarization form converter is located in the light path where the first the reflected beams, for by the first the reflected beams Polarization state from the second polarization converted be the first polarization state；Second polarization form converter is located at where the second transmitted light beam Light path on, for by the polarization state of the second transmitted light beam from the second polarization converted be the first polarization state；

   Alternatively, first polarization form converter is located in the light path where the second the reflected beams, for by the second the reflected beams Polarization state from the first polarization converted be the second polarization state；Second polarization form converter is located at where the first transmitted light beam Light path on, for by the polarization state of the first transmitted light beam from the first polarization converted be the second polarization state；

   The optical modulator, for unified the first transmitted light beam with the first polarization state or the second polarization state, second to be transmitted Light beam, the first the reflected beams and the second the reflected beams are modulated to left circularly polarized light and right-circularly polarized light according to frame sequential.
4. 4. the polarization modulating arrangement of stereoprojection light as claimed in claim 3, it is characterised in that the polarization beam splitting assembly bag Two substrates are included, two substrates are connected with each other and are in the shape of the letter V, and the propagation of the protrusion direction and projected light beam for the formed ridge that is connected Direction contrary；

   Polarization spectro layer is equipped with described two substrates, and the polarization spectro layer transmissive of first substrate therein goes out first Transmitted light beam and reflect the first the reflected beams, the polarization spectro layer transmissive of second substrate goes out the second transmitted light beam and reflects Second the reflected beams.
5. 5. the polarization modulating arrangement of stereoprojection light as claimed in claim 4, it is characterised in that：

   Second polarization form converter is attached at the second substrate transmissive and goes out on the surface of the second transmitted light beam；

   Go out alternatively, second polarization form converter is attached at the first substrate transmissive on the surface of the first transmitted light beam.
6. 6. the polarization modulating arrangement of stereoprojection light as claimed in claim 3, it is characterised in that the polarization beam splitting assembly is Polarization splitting prism group；The polarization splitting prism group is bonded by least three prisms to be formed, and joint place has two polarizations point Photosphere, two polarization spectro layers are connected with each other and are in the shape of the letter V, and the propagation of the protrusion direction and projected light beam for the formed ridge that is connected Direction contrary, and the first polarization spectro layer transmissive therein goes out the first transmitted light beam and reflects the first the reflected beams, the Two polarization spectro layer transmissive go out the second transmitted light beam and reflect the second the reflected beams.
7. 7. the polarization modulating arrangement of stereoprojection light as claimed in claim 6, it is characterised in that：

   Second polarization form converter is packaged in the polarization splitting prism group, and can positioned at the second polarization spectro layer Transmit the side of the second transmitted light beam；

   Alternatively, second polarization form converter is packaged in the polarization splitting prism group, and positioned at the described first polarization point Photosphere transmissive goes out the side of the first transmitted light beam.
8. 8. the polarization modulating arrangement of stereoprojection light as claimed in claim 1, it is characterised in that first polarization state and Two polarization states are linear polarization and the polarization direction of the two is orthogonal；The polarization state modulation component includes：Polarization converted unit And optical modulator；

   The polarization converted unit is at the same time positioned at the light path where first the reflected beams and the second transmitted light beam institute Light path on；

   Alternatively, the polarization converted is at the same time positioned at the light path where the second the reflected beams and the light path where the first transmitted light beam On；

   The optical modulator, for unified the first transmitted light beam with the first polarization state or the second polarization state, second to be transmitted Light beam, the first the reflected beams and the second the reflected beams are modulated to left circularly polarized light and right-circularly polarized light according to frame sequential.
9. 9. the polarization modulating arrangement of stereoprojection light as claimed in claim 8, it is characterised in that the polarization beam splitting assembly bag Two substrates are included, two substrates are connected with each other and are in the shape of the letter V, and the propagation of the protrusion direction and projected light beam for the formed ridge that is connected Direction is identical；

   Described two substrates include first substrate and second substrate, and polarization is equipped with the first substrate and the second substrate Beam splitter layer, and the polarization spectro layer transmissive of first substrate therein goes out the first transmitted light beam and reflects the first reflected light Beam, the polarization spectro layer transmissive of second substrate go out the second transmitted light beam and reflect the second the reflected beams, wherein, by described First the reflected beams that the polarization spectro layer beam splitting of one substrate goes out may pass through the second substrate again by second light path The direction of propagation is adjusted the direction to where imaging surface by direction adjustment component, by the polarization spectro layer beam splitting of the second substrate Second the reflected beams gone out may pass through the first substrate and adjust component by the direction of propagation by first optical path direction again Adjust the direction to where imaging surface.
10. 10. the polarization modulating arrangement of stereoprojection light as claimed in claim 9, it is characterised in that the polarization converted list Member is attached at the second substrate transmissive and goes out on the surface of the second transmitted light beam and the first the reflected beams；

    Alternatively, the polarization converted unit, which is attached at the first substrate transmissive, goes out the first transmitted light beam and the second reflected light On the surface of beam.
11. 11. the polarization modulating arrangement of stereoprojection light as claimed in claim 8, it is characterised in that the polarization beam splitting assembly For polarization splitting prism group；The polarization splitting prism group is bonded by least three prisms to be formed, and joint place has two polarizations Beam splitter layer, two polarization spectro layers are connected with each other and are in the shape of the letter V, and be connected the formed protrusion direction of ridge and the biography of projected light beam It is identical to broadcast direction, and the first polarization spectro layer transmissive therein goes out the first transmitted light beam and reflects the first the reflected beams, Second polarization spectro layer transmissive goes out the second transmitted light beam and reflects the second the reflected beams, wherein, by the described first polarization point First the reflected beams that photosphere beam splitting goes out may pass through the second polarization spectro layer and be adjusted again by second optical path direction The direction of propagation is adjusted the direction to where imaging surface by component, second reflected light gone out by the second polarization spectro layer beam splitting Beam may pass through the first polarization spectro layer and again be adjusted the direction of propagation to imaging table by first optical path direction adjustment component Direction where face.
12. 12. the polarization modulating arrangement of stereoprojection light as claimed in claim 11, it is characterised in that the polarization converted list Member is packaged in the polarization splitting prism group, and goes out the second transmitted light beam and positioned at the second polarization spectro layer transmissive The side of one the reflected beams；

    Alternatively, the polarization converted unit is packaged in the polarization splitting prism group, and it is located at first polarization spectro Layer transmissive goes out the side of the first transmitted light beam and the second the reflected beams.
13. 13. such as the polarization modulating arrangement of claim 1 to 12 any one of them stereoprojection light, it is characterised in that described inclined The polarization spectro layer for being used in beam splitting component carry out projected light beam polarization beam splitting that shakes is wire grid construction, wherein, beam splitting goes out first Each grid arrangement direction of the wiregrating part of transmitted light beam and the first the reflected beams, goes out the second transmitted light beam and second anti-with beam splitting Each grid arrangement direction of the wiregrating part of irradiating light beam is mutually orthogonal.
14. A kind of 14. stereoscopic image showing system, it is characterised in that including：

    Projector, the projected light beam of left-eye images information is carried for being projected successively with frame sequential and carries right-eye image The projected light beam of information；

    The polarization modulating arrangement of claim 1 to 13 any one of them stereoprojection light；

    Curtain, for each projected light beam with identical polarization state modulated for the polarization modulating arrangement of the stereoprojection light It is imaged, and imaging is reflexed to the 3D glasses of user's wearing.
15. 15. a kind of polarization modulation method of stereoprojection light, it is characterised in that the described method includes following step：

    By the projected light beam beam splitting for carrying image information for the first transmitted light beam with the first polarization state, with the second polarization Second transmitted light beam of state, the first the reflected beams with the second polarization state and the second the reflected beams with the first polarization state； Wherein, the first transmitted light beam and the second transmitted light beam gone out by beam splitting is propagated to the direction where imaging surface, and described first Image space of the transmitted light beam with first the reflected beams on imaging surface is identical, second transmitted light beam and described the Image space of two the reflected beams on imaging surface is identical；

    Adjust the direction of propagation of the first the reflected beams and the second the reflected beams so that the first the reflected beams and the second the reflected beams to Propagate in direction where imaging surface；

    It is inclined to the part or all of progress in the first transmitted light beam, the second transmitted light beam, the first the reflected beams, the second the reflected beams Polarization state is modulated so that the first transmitted light beam, the second transmitted light beam, the first the reflected beams, the second the reflected beams have identical inclined Polarization state.