CN103760679A - Light recovery device and corresponding stereoscopic imaging system - Google Patents

Abstract

The present invention provides a light recycling device, comprising: a beam splitter with multiple reflective surfaces, and a sub-light path corresponding to each reflective surface, wherein the beam splitter is used to transmit the first polarized light and reflect the second polarized light, and split the light The reflective surfaces of the device are used to divide the incident image into multiple sub-images, and each of the sub-light paths reflects the corresponding sub-image to a preset area, so that the sub-images are fused into a complete image. The invention can significantly reduce the volume of the light recovery device.

Description

Light recovery device and corresponding stereoscopic imaging system

technical field

The invention relates to the field of optical technology, in particular, the invention relates to a light recovery device and a corresponding stereoscopic imaging system.

Background technique

In the prior art, in order to obtain the 3D effect, the ordinary polarized light 3D system needs to hit the mixed polarized light (or natural light) emitted by the projector on the polarizer to obtain linearly polarized light. For example, Figure 1 shows a typical ordinary Schematic diagram of the technical principle of obtaining linearly polarized light in the polarized light 3D system, in which: the P light hits the screen through the polarizer, and the S light is reflected back by the polarizer. Like this, in the whole optical path, S light is wasted in vain. Therefore, the brightness of visible light on the actual screen is only half of that before passing through the polarizer.

In order to solve the above problems, people have proposed a light recycling stereoscopic imaging system. The mixed polarized light (or natural light) emitted by the projector is first divided into P light and S light through the beam splitter. The P light directly passes through the beam splitter, and then passes through the polarizer. When it hits the screen, the S light undergoes reflection and related processing (such as adjustment of polarization characteristics), and then is projected onto the screen so that the reflected image of the original S light overlaps with the P light image. In this way, the wasted S light in Fig. 1 is recycled again. Through this recycling, the light intensity can be greatly improved, so that the brightness of the polarized light output by the polarizer can be doubled.

However, since the light emitted by the projector is scattered light, the spot of the image will become larger and larger during the propagation along the optical path. After the S-ray image is reflected by the beam splitter, the optical path increases, resulting in the following three Aspects of the problem:

1) Large size, causing inconvenience in transportation, packaging, installation and maintenance. For example, a large enough window is required for screening.

2) Heavy weight; causing inconvenience in transportation, packaging, installation and maintenance.

3) The cost is high, the cost of related accessories and the cost increase due to the large volume and weight.

Therefore, there is an urgent need for a solution that can reduce the size, weight and cost of the system.

Contents of the invention

The task of the present invention is to provide a light recycling solution that reduces the volume, weight and cost of the system.

In order to achieve the above-mentioned purpose of the invention, the present invention provides a light recycling device, including: a beam splitter with multiple reflective surfaces, and a sub-optical path corresponding to each reflective surface, the beam splitter is used to transmit the first polarized light and reflect the second polarized light. Two polarized light, each reflective surface of the beam splitter divides the incident image into a plurality of sub-images, and each sub-optical path includes a reflector matched with the corresponding reflective surface, and the size of the reflector is the same as that divided by the reflective surface of the beam splitter The sub-images are adapted in size and arranged at positions close to the matching reflective surface, and each sub-light path reflects the corresponding sub-image to a preset area, so that the sub-images are fused into a complete image.

Wherein, the beam splitter is a beam splitting prism with multiple reflective surfaces.

Wherein, the beam splitter is a four-splitting beam splitting prism with four reflecting surfaces.

Wherein, the beam splitter is a two-splitting beam splitting prism with two reflecting surfaces.

Wherein, each sub-optical path sequentially includes the reflector and a back-end processing unit, and the back-end processing unit is used to rotate the polarization angle of the second polarized light to convert it into the first polarized light.

Wherein, the reflectors of each sub-optical path are installed on the omnidirectional adjustment mirror frame.

Wherein, each sub-optical path is also used to fuse each sub-image into a complete image and superimpose it with the image of the transmitted first polarized light.

The present invention also provides a stereoscopic imaging system, comprising: a projector, and a light recovery device arranged on the output optical path of the projector, the light recovery device is the aforementioned light recovery device, and is used to polarize the stereoscopic image sequence output by the projector. modulation, the image of the first polarized light and the image of the second polarized light output by the light recovery device are used as left and right eye images respectively.

The present invention also provides another stereoscopic imaging system, comprising: a plurality of projectors, a light recovery device arranged on the output optical path of each projector, the light recovery device is the aforementioned light recovery device, and is used for outputting the stereoscopic image of the projectors. The image sequence is modulated with polarized light, and each light recycling device outputs an image with a single polarization angle as a left-eye or right-eye image.

Compared with the prior art, the present invention has the following technical effects:

1. The present invention can significantly reduce the volume of the light recovery device.

2. The present invention facilitates adjustment of the projection positions of the sub-images, so that the sub-images can be perfectly fused.

Description of drawings

Fig. 1 shows a schematic diagram of the technical principle of obtaining linearly polarized light in a typical ordinary polarized light 3D system;

Fig. 2 shows a schematic diagram of the light path of the light recycling device according to an embodiment of the present invention;

Fig. 3 shows a schematic diagram of light splitting of a 4-split beam splitting prism;

Fig. 4 shows an example of the sub-image divided into four quadrants of the incident image by a 4-splitting beam-splitting prism;

Fig. 5 shows a schematic diagram of the moving direction of the sub-image on the screen;

FIG. 6 shows a schematic structural diagram of a stereoscopic imaging system based on a stand-alone solution in another embodiment of the present invention;

Fig. 7 shows a schematic structural diagram of a stereoscopic imaging system based on a two-device solution in another embodiment of the present invention.

Detailed ways

First of all, it should be noted that the P-polarized light and S-polarized light described in this article are synonymous with two different linearly polarized lights. P-polarized light and S-polarized light can have multiple meanings, for example, but not limited to the following Any one of a to f is defined:

a.P polarized light is horizontal linearly polarized light, and S polarized light is vertical linearly polarized light

b. P polarized light is vertical linearly polarized light, S polarized light is horizontal linearly polarized light

c. P polarized light is 45 degree linearly polarized light, S polarized light is 135 degree linearly polarized light

d. P-polarized light is 135-degree linearly polarized light, and S-polarized light is 45-degree linearly polarized light

e.P polarized light is transmitted linearly polarized light, and S polarized light is reflected linearly polarized light

f. P polarized light is reflected linearly polarized light, and S polarized light is transmitted linearly polarized light

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Figure 2 shows a light recovery device provided according to an embodiment of the present invention, including: a dichroic prism with 4 reflective surfaces, reflecting mirrors 1a, 1b, 1c, 1d respectively corresponding to the respective reflective surfaces of the dichroic prism, the first A reflective surface 1a and its back-end processing unit form the first sub-optical path (upper sub-optical path), the second reflective surface 1b and its back-end processing unit form the second sub-optical path (lower sub-optical path), and the third reflective surface 1c and its subsequent The end processing unit constitutes the third sub-optical path (left sub-optical path), and the fourth reflective surface 1d and its back-end processing unit constitute the fourth sub-optical path (right sub-optical path). In addition, a corresponding back-end processing unit is also arranged behind the dichroic prism.

In this embodiment, the optical segmentation technology is used to divide a complete picture into multiple independent small pictures for separate processing, and finally the picture fusion technology is used to merge the divided small pictures into a complete picture. In the original light recovery device, a beam splitter is used to split the P polarized light and S polarized light for the complete image, and then the separated P polarized light and S polarized light are processed separately. In this embodiment, a dichroic prism with four reflective surfaces is used, and each reflective surface of the dichroic prism can reflect S polarized light and transmit P polarized light. Figure 3 shows a schematic diagram of the light splitting of the dichroic prism in this embodiment, in which P polarized light is transmitted, and the picture of S polarized light is divided into four by four reflecting surfaces (as shown in Figure 4), forming four quadrant sub-pictures, and reflect in four directions of up, down, left, and right respectively, and the reflectors of the up, down, left, and right sub-light paths respectively correspond to the sub-pictures reflected in these four directions. In one example, the mirrors of the upper, lower, left and right sub-optical paths respectively correspond to and reflect the sub-images of the first, fourth, second and third quadrants. In this way, when the mixed polarized light (or natural light) image enters the beam splitter, a transmitted P polarized light image and four S polarized light sub-images reflected in four directions will be obtained. The 4 sub-images of S polarized light are reflected by the corresponding mirrors, propagate along the corresponding sub-optical paths to their respective preset designated areas (such as the corresponding areas on the screen), and can be seamlessly stitched through image fusion technology to form a complete image Image.

In this embodiment, the back-end processing unit of each sub-optical path is used to adjust S-polarized light to P-polarized light (for example, rotate the polarization angle of S-polarized light to obtain P-polarized light), so that the complete image after fusion is a P-polarized image, and It is superimposed with the P polarized image transmitted from the beam splitting prism and hits the screen to increase the brightness.

Further, with reference to Fig. 2, in this embodiment, the reflectors of each sub-optical path can be installed on the omnidirectional adjustment mirror frames 2a, 2b, 2c, 2d matched therewith, by adjusting the omnidirectional adjustment mirror frames, it can be conveniently Adjust the projection position of each sub-image so that the two sub-images projected on the screen are seamlessly spliced and fused into a complete image (the moving direction of the sub-images on the screen is shown in Figure 5). This fused image is superimposed with the image transmitted from the beam-splitting prism and hits the screen to increase the brightness of the screen.

This embodiment maintains the characteristics of high light efficiency and high image quality of the traditional light recovery device, because the optical segmentation technology is used to divide the image into small blocks for processing, which greatly reduces the physical size of the optical components and reduces the size of the system volume, reducing the weight of the system, this is because the inventors have found through research: 1) the reflective surface of the dichroic prism divides the image of the incident window into multiple sub-images, so that the size of the sub-images will be reduced by at least half, so that the reflection surface of the reflector The size (such as the size in the latitude direction) can be reduced accordingly, so that the area of the window required by each corresponding reflector is significantly reduced; 2) Due to the reduced size of the reflector, the reflector can be arranged more compactly, such as arranged in Closer to the position of the beam splitter prism (as long as the distance between the reflected S-polarized light and the transmitted P-polarized light image does not interfere with each other), the optical path of the sub-image from the reflective surface of the beam-splitter prism to the corresponding mirror is also reduced accordingly , thereby reducing the spread of the image as the optical path increases, so that the incident window of the mirror can be further reduced. Therefore, under the combined effect of the above two factors, the size of the mirror and subsequent optical elements and the distance between each element can be significantly reduced, so that the volume of the optical path corresponding to each sub-image is much smaller than that of a traditional light recycling device. 1/4 of the reflected light path. Therefore, although this embodiment requires four light paths to recycle the reflected S-polarized light (traditional light recovery devices only need one light path to recycle the reflected S-polarized light), this embodiment can still significantly reduce the overall volume of the system.

According to other embodiments of the present invention, the present invention can also use beam splitters with other numbers (greater than or equal to 2) of reflecting surfaces, such as 2-split beam-splitting prisms, 3-split beam-splitting prisms, and 5-split beam-splitting prisms. 2. The dichroic prism may be a triangular prism, including a bottom surface and two side surfaces, wherein the two sides are reflective surfaces, which can transmit the first polarized light and reflect the second polarized light, and the bottom surface can transmit the first polarized light.

According to another aspect of the present invention, the light recovery device based on the above-mentioned embodiments can respectively implement a stereoscopic imaging system based on a single-device solution and a stereoscopic imaging system based on a dual-device solution.

According to an embodiment of the present invention, as shown in FIG. 6 , in stand-alone applications, a light recycling device based on the foregoing embodiments is added to the output light path of the projector to perform polarization modulation on the output stereoscopic image sequence. Among them, at this time, the back-end processing unit in each sub-optical path of the light recovery device does not need to convert S polarized light into P polarized light, but directly uses the fused S polarized light as the left eye (or right eye) image, and at the same time converts the transmitted P polarized light directly as a right-eye (or left-eye) image. The screen adopts a metal screen, so that the polarized light keeps the polarization direction unchanged after being reflected by the screen. At the same time, the projector outputs a 3D synchronous signal to the controller, and the controller outputs a 3D control signal according to the 3D synchronous signal. When the image sequence reflected by the screen passes through the polarized 3D glasses, the left and right eyes can see the left and right eye images respectively, thereby synthesizing a stereoscopic image in the brain.

According to an embodiment of the present invention, as shown in FIG. 7 , in the dual-machine application based on the foregoing embodiments, the two projectors respectively output a left-eye image sequence and a right-eye image sequence. Add a light recovery device based on the aforementioned embodiment on the output light paths of the two projectors, respectively perform polarized light modulation on the left-eye image sequence and the right-eye image sequence output by the two projectors, and then project a single polarization direction on the screen. A sequence of left and right eye images whose polarization angles are perpendicular to each other. The screen is a metal screen to ensure that the polarization direction of the polarized light remains unchanged after being reflected by the screen. When the image sequence reflected by the screen passes through the polarized 3D glasses, the left and right eyes can respectively see the image sequence for the left and right eyes, thereby synthesizing a stereoscopic image in the brain.

In addition, the light recycling scheme of the present invention is also applicable to multi-camera imaging, which is easily understood by those skilled in the art.

The above descriptions are only illustrative specific implementations of the present invention, and are not intended to limit the scope of the present invention. Any equivalent changes, modifications and combinations made by those skilled in the art without departing from the concept and principle of the present invention shall fall within the protection scope of the present invention.

Claims (10)

1. a light retracting device, comprise: the optical splitter with a plurality of reflectings surface, and the sub-light path that corresponds respectively to each reflecting surface, wherein, described optical splitter is for the first polarized light and reflection second polarized light of transmission incident image, described a plurality of reflectings surface of optical splitter are for being divided into a plurality of subimages by incident image, and the sub-light path described in each reflexes to predeterminable area by corresponding subimage, makes each subimage be fused into complete image.

2. smooth retracting device according to claim 1, is characterized in that, described optical splitter is the Amici prism with a plurality of reflectings surface.

3. smooth retracting device according to claim 2, is characterized in that, described optical splitter is to have four of 4 reflectings surface to cut apart Amici prism.

4. smooth retracting device according to claim 2, is characterized in that, described optical splitter is to have two of 2 reflectings surface to cut apart Amici prism.

5. smooth retracting device according to claim 1, it is characterized in that, every described sub-light path comprises the catoptron matching with corresponding reflecting surface successively, the size of the subimage that the size of described catoptron and spectrophotometric reflection face are partitioned into adapts, and is arranged in the position near the reflecting surface coordinating.

6. smooth retracting device according to claim 5, is characterized in that, described in each, the catoptron of sub-light path is installed on omnidirectional's adjustment mirror holder.

7. smooth retracting device according to claim 5, is characterized in that, every described sub-light path also comprises back-end processing unit.

8. smooth retracting device according to claim 7, it is characterized in that, described back-end processing unit, for the polarization angle of rotating described the second polarized light, makes it convert the first polarized light to, and makes each subimage be fused into after complete image the image stack with the first polarized light of transmission.

9. a stereo imaging system, comprise: projector, be arranged on the light retracting device on projector output light path, described smooth retracting device is the light retracting device described in any one in described claim 1 to 7, for the sequence of stereoscopic images of projector output is carried out to polarized light modulation, the image of described the first polarized light of described smooth retracting device output and the image of described the second polarized light are respectively as left-and right-eye images.

10. a stereo imaging system, comprise: two projectors, be separately positioned on two light retracting devices on every projector output light path, described smooth retracting device is the light retracting device described in any one in described claim 1 to 8, for the sequence of stereoscopic images of projector output is carried out to polarized light modulation, the image that described in each, light retracting device is all exported single polarization angle is as left eye or eye image.

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