CN2620297Y - Object surface regulator of optical projecting system based on focus out depth analysis - Google Patents

Abstract

The utility model discloses a matter surface adjustment device for an optical projection system that is based on the defocus depth analysis, sequentially comprising an illuminating light source, an illuminating and decompn system, red, blue, green LCDs and an adjustment structure, an optical synthesis and projection imaging system, and a projection screen that is provided with a plurality of CCDs. An image collection group of each CCD on the projection screen has the following structure: the projection screen is provided with frosted glass, the back of which is provided with a lens; the back of the lens is provided with a CCD device; the frosted glass and the CCD surface respectively grip the shared lens, which makes the image on the projection screen firstly diffused by the frosted glass, and then shrunk and imaged on the CCD surface by means of a convex lens; a frosted glass pressure coil, a front pressure coil of the projection screen, a back pressure coil of the projection screen and an adjusting connected coil are all used to fix the frosted glass, the lens and the CCD device; the rotation and adjustment of the connected coil make the frosted glass clearly imaged on the surface of the CCD device; a propping screw is used to fix each pressure coil and the connected coil. The utility model has advantages that: firstly, the adjustment has a high accuracy; secondly, the adjustment has a fast speed; thirdly, the operation is simple.

Description

Object Plane Adjustment Device of Optical Projection System Based on Defocus Depth Analysis

Technical field

The utility model relates to an object plane adjustment device for an optical projection system based on defocus depth analysis.

Background technique

With the continuous advancement of various optical unit technologies, optical projection technology is gradually becoming mature, and mass production is being or has already been formed. The most typical ones are multimedia digital projectors, digital projection TVs, etc. The object plane of this type of projection system is generally LCD or other standard plates, films, etc. Because there are certain errors in the manufacturing process of optical parts and mechanical parts, and the entire optical system is very sensitive to errors, the installation error of LCD or target plate, and the manufacturing error of projection lens will make the projected image of the entire projection system not good. After adjustment, the projected image cannot be viewed at all.

Taking digital projection TV as an example (the principle of multimedia projectors is basically the same), the projection system consists of light source and light splitting part, three LCDs, three-color synthesis and projection lens and other components. Three of the LCDs display red, green, and blue images respectively, which are illuminated by the light source, synthesized by the synthesis system, and projected onto the display screen by the projection lens. The three LCDs are respectively fixed by corresponding clamps with adjustment mechanisms. Each LCD may have errors such as tilt, translation, and rotation, which may cause the projected images of each color to be unclear, the starting position is wrong, and the image is rotated. When the projection images of the three LCDs are combined, three colors will appear. Color misalignment. Therefore, it is necessary to adjust six degrees of freedom for each LCD, and a total of 18 degrees of freedom are required for adjustment.

In order to adjust the above 18 degrees of freedom, the following steps are generally adopted now:

1) To project an LCD (monochrome), first observe the sharpness of the center of the image on the projection screen, and adjust the focus position of the LCD;

2) Observe the clarity of the four sides of the image separately, and adjust the tilt of the LCD;

3) Observe the inclination of the horizontal and vertical lines of the image, and adjust the rotation direction of the LCD;

4) Perform the same adjustment on the other two LCDs;

5) Three LCDs (red, green and blue) are projected at the same time, and the relative positions of the three LCDs are adjusted to make the color registration correct.

During the entire adjustment process, the debugger needs to have sufficient experience, and the labor intensity is very high. The adjustment accuracy largely depends on the subjectivity of the debugger, and the adjustment speed is very slow. This debugging method obviously cannot meet the needs of mass production.

Contents of invention

The purpose of the utility model is to provide an optical projection system object plane adjustment device based on defocus depth analysis.

The object plane adjustment device of the optical projection system based on defocus depth analysis has an illumination source, an illumination and light splitting system, red, blue, green LCD and adjustment structure, an optical synthesis and projection imaging system, and a projection screen equipped with multiple CCDs. The structure of each group of CCD image acquisition groups on the projection screen is as follows: frosted glass is installed at the position of the projection screen, a lens is installed behind it, and a CCD device is installed behind the lens. After the image diffuses through the frosted glass, it is narrowed and imaged on the surface of the CCD by the lens. The ground glass pressure ring, the front pressure ring of the projection screen, the rear pressure ring of the projection screen and the adjusting ring are used to fix the ground glass, the lens and the CCD device. The ring is rotated and adjusted so that The frosted glass is clearly imaged on the surface of the CCD device, and the top screw is used to fix each pressure ring and adapter ring.

Advantage of the utility model:

1) High adjustment accuracy (including focus, color registration, tilt adjustment, rotation adjustment, etc.), not affected by the subjective factors of the operator, and the accuracy is guaranteed by the control system;

2) The adjustment speed is fast, and the adjustment amount of 18 degrees of freedom is given at one time, which is suitable for large-scale production;

3) The operation is simple, and the operator does not need a lot of experience.

Description of drawings

Figure 1 is a schematic diagram of the structure of the object plane adjustment device of the optical projection system based on the analysis of the defocus depth. Projection imaging system 5, green LCD and adjustment mechanism 6, projection screen 7 equipped with multiple CCDs;

Fig. 2 is the installation position distribution diagram of the color CCD on the projection screen in the object plane adjustment device of the optical projection system based on defocus depth analysis;

Fig. 3 is a schematic diagram of the structure of the CCD image acquisition group on the projection screen in the object plane adjustment device of the optical projection system based on defocus depth analysis;

Figure 4 is a unit of the standard image for debugging in the object plane adjustment device of the optical projection system based on defocus depth analysis. In the figure, A is a unit of the standard image for debugging, B is the red component pattern, C is the green component pattern, and D It is a blue component pattern.

Detailed ways

The method of adjusting the object plane of the optical projection system based on the analysis of the depth of defocus is as follows: multiple CCD image acquisition components are installed on the projection screen of the projection optical system to obtain images, and the defocus of the LCD on the object plane of the optical projection system is obtained by analyzing the images. The amount, the amount of inclination in the horizontal direction, the amount of inclination in the vertical direction, the amount of rotation, and the relative position deviation of the three LCDs give the adjustment parameters.

Said CCD image acquisition assembly is: frosted glass is installed at the position of the projection screen, an imaging lens is installed thereafter, a CCD device is installed at the rear of the lens, the frosted glass and the CCD surface are respectively conjugated with respect to the lens, so that the image on the projection screen diffuses through the frosted glass. After being shot, the image is imaged on the surface of the CCD through the lens.

Obtaining the defocus amount of the object plane LCD of the optical projection system through image analysis is to calculate the defocus amount of multiple images by using the defocus depth method to obtain the defocus amount of the image, thereby obtaining the defocus amount of the object plane LCD. Use the defocus depth method to calculate the size of the diffuse spots of each color separation image in each image, and then combine the optical parameters of the projection optical system to calculate the defocus amount of each color separation image, so as to calculate the corresponding LCD. The axial offset of the position. Through the calculation of each color separation image, three degrees of freedom of each LCD can be determined: the defocus amount along the optical axis direction, and the two deflection amounts in the vertical optical axis direction.

The so-called defocus depth method can be briefly described as follows: the standard image used in this patent is a lot of pure color lines, the image obtained by the CCD can be regarded as a step function in mathematics when the focus is correct, the system output gets a straight edge response, and the straight edge The derivative of the edge response is the line spread function of the system. Using this relationship, the size of the diffuse spot can be estimated from the straight edge response of the imaging system.

According to the simple relationship of geometric optics, the defocusing amount of the image side of the image can be easily obtained from the diffuse spot R, and the defocusing amount of the object plane can be further obtained.

Obtaining the horizontal inclination of the object plane LCD of the optical projection system through image analysis is: through the analysis and calculation of the dislocated two images obtained by CCD2 and CCD3, the corresponding two points in the horizontal direction on the projection object plane LCD are obtained. The amount of defocus, so as to obtain the amount of inclination in the horizontal direction of the LCD;

Obtaining the inclination in the vertical direction of the object plane LCD of the optical projection system through image analysis is: through the analysis and calculation of the two images obtained by the CCD4 and CCD5 that are dislocated in the vertical direction, the two vertical directions on the corresponding projection object plane LCD are obtained. The amount of defocus of the point, so as to obtain the tilt amount of the vertical direction of the LCD;

Obtain the rotation amount of the object plane LCD of the optical projection system and the relative position deviation of the three LCDs by analyzing the image, using a set of standard color patterns for adjustment, by calculating the theoretical white or color lines on each color separation image Positional relationship, calculate the relative position deviation of the three LCDs, calculate the horizontality and verticality of the horizontal and vertical lines in the image in theory, calculate the rotation around the axis of the three LCDs and the relative initial positions of the three LCDs Deviation.

The adjustment system of the utility model comprises a standard image for debugging, a multi-channel CCD image acquisition component, a computer control system and processing software.

First, the computer control software generates a set of standard images for debugging, including the color separation images output by the red, green, and blue LCDs, which are synthesized into a set of color debugging images.

The color debugging image is projected by the initially installed projection system, and a color debugging image is obtained on the projection screen. The image may have a variety of error defects, including: out of focus, image tilt or rotation, three colors not overlapping, and more.

The object plane adjustment device of the optical projection system based on defocus depth analysis has an illumination source, illumination and spectroscopic system, red, blue, green LCD and adjustment structure, optical synthesis and projection imaging system, projection screen equipped with multiple CCDs, projection The structure of each group of CCD image acquisition groups on the screen is: frosted glass 14 is installed at the projection screen 9 positions, a lens 11 is installed thereafter, and CCD device 12 is installed at the rear of the lens, and ground glass 14 and CCD surface are respectively conjugated with respect to the lens, so that After the image on the projection screen diffuses through the ground glass, it is imaged on the surface of the CCD through the lens. The ground glass pressure ring 8, the front pressure ring 13 of the projection screen, the rear pressure ring 15 of the projection screen and the adjustment ring 17 are used to fix the ground glass, the lens and the CCD. The device and the adapter ring are rotated and adjusted so that the frosted glass is clearly imaged on the surface of the CCD device, and the top screw 16 is used to fix each pressure ring and the adapter ring.

Therefore, the error in each direction of the three LCDs can be calculated by analyzing the diffuse spots, line clarity and relative position of each color separation map of multiple color images, and all 18 degrees of freedom are determined. According to the adjustment plan given by the computer software, the operator can easily adjust all directions of the LCD, and the whole system is adjusted quickly. Adjustment and observation do not require too much prior experience of the operator, and the adjustment accuracy is guaranteed by the system and is not affected by the operator's subjective factors.

Figure 1 shows the main components of the projection system: light source, spectroscopic lighting system, three LCDs with adjustment structure, optical synthesis and projection imaging system, and projection display screen.

Figure 2 is a distribution diagram of the installation positions of the color CCD on the projection screen. As a typical example, five CCDs are placed on the projection screen, which are respectively installed in the center (CCD1), left middle (CCD2), right middle (CCD3), upper middle (CCD4) and lower middle (CCD5).

Figure 3 shows the structure of each group of CCD image acquisition groups. A frosted glass 14 is installed at the position of the projection screen 9, a lens 11 is installed behind it, and a CCD device 12 is installed at the rear of the lens. The frosted glass 14 and the CCD surface are respectively conjugated with respect to the lens, so that after the image on the projection screen diffuses through the frosted glass, it passes through the lens. Zoom out and image on the surface of the CCD. Frosted glass pressure ring 8, projection screen front pressure ring 13, projection screen rear pressure ring 15 and adjustment ring 17 are used to fix the ground glass, lens and CCD device, and the connection ring can be rotated and adjusted so that the ground glass is clearly imaged on the surface of the CCD device . Jack screw 16 is used for fixing.

表示红色，

表示绿色， 表示蓝色，

表示黄色(红加绿色)， 表示青色(绿加蓝色)，

表示品红色(红加蓝色)，

表示白色(红加绿加蓝色)，“空白”表示黑色。调试用图案可以是多种形式的，本图仅为一种典型形式。Fig. 4 is a unit of a standard image for debugging in a form (the complete pattern is the multiple cycle of accompanying drawing 4, guaranteeing that each piece of CCD installed on the projection screen can collect more than a complete unit). FIG. 4R is a red component pattern of a standard image, FIG. 4G is a green component pattern, and FIG. 4B is a blue component pattern. In the picture:

means red,

means green, means blue,

Indicates yellow (red plus green), Represents cyan (green plus blue),

Indicates magenta (red plus blue),

means white (red plus green plus blue), and "blank" means black. The patterns for debugging can be in various forms, and this figure is only a typical form.

Claims (1)

1. An optical projection system object plane adjustment device based on defocus depth analysis, characterized in that: it has an illumination source, illumination and spectroscopic system, red, blue, green LCD and adjustment structure, optical synthesis and projection imaging accordingly system, a projection screen equipped with multiple CCDs, the structure of each group of CCD image acquisition groups on the projection screen is: frosted glass (14) is installed at the position of the projection screen (9), and a lens (11) is installed behind it. The CCD device (12) is installed, and the frosted glass (14) and the CCD surface are respectively conjugated with respect to the lens, so that after the image on the projection screen is diffused by the frosted glass, the image is narrowed and imaged on the surface of the CCD through the lens, the frosted glass pressure ring (8), the projection screen The front pressure ring (13), the projection screen rear pressure ring (15) and the adjustment ring (17) are used to fix the frosted glass, the lens and the CCD device. Screws (16) are used to fix each pressure ring and adapter ring.

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