White balance debugging method and system based on LCOS display technology

Abstract

The invention relates to the technical field of white balance debugging, in particular to a white balance debugging method and system. The white balance debugging method comprises the following steps: S1, a debugging device sends a control instruction; s2, projecting RGB (Red, Green and Blue) images with different brightness on the diffusion sheet by the image imaging unit; s3, the color analyzer obtains the RGB images, measures color coordinates and brightness values of the RGB images with different brightness at the current temperature, and sends the color coordinates and the brightness values to the debugging equipment; s4, the debugging equipment creates a brightness calibration point in the CIE Yxy color space, and calculates RGB brightness contribution ratios under different brightness; s5, the debugging equipment calculates a white brightness value which can be realized by each brightness calibration point; s6, the debugging equipment calculates an RGB current driving value under the current brightness; s7, the debugging equipment generates a calibration data table and sends the calibration data table to the HUD control board; and S8, the HUD control panel receives and stores the calibration data table. The method can solve the problems of HUD luminous efficiency difference and color temperature shift.

Description

Technical Field

[0001] The present invention relates to the technical field of white balance adjustment, and in particular to a white balance adjustment method and system. Background Art

[0002] With the continuous development of the automotive industry, the application of head up display (HUD) systems in vehicles is becoming more and more common. The head up display system can project important driving information directly onto the windshield, so that the driver does not need to look down at the dashboard, thereby improving driving safety and convenience. Among the many display technologies, liquid crystal silicon (LCOS) display technology is widely used in automotive head up display systems due to its high resolution, high brightness and color reproduction.

[0003] However, liquid crystal on silicon display technology has white balance offset problems due to differences in the installation of three-color LED light sources, differences in luminous efficiency, and under different temperature conditions. Due to the complex and changeable working environment of the car, the temperature inside the car may experience large changes, which poses a severe challenge to the color performance of the LCOS display. Without effective white balance calibration, the color accuracy and consistency of the LCOS display will be difficult to guarantee, which will in turn affect the display effect and driving experience of the HUD system. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a white balance debugging method and system based on LCOS display technology. The above system can effectively realize white balance calibration, ensure the color accuracy and consistency of the LCOS display, thereby improving the display effect and driving experience of the HUD system; the above method can solve the problem of different luminous efficiency and inconsistent color temperature caused by installation differences and differences in the BIN values ​​of the three-color LED light sources, and can solve the problem that the three-color LED light sources will have color temperature deviation under different ambient temperature conditions, thereby causing the color temperature deviation of the mixed white light.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a white balance debugging method based on LCOS display technology, comprising the following steps:

[0007] S1: The debugging device controls the HUD control board to send control instructions to the image imaging unit;

[0008] S2: the image forming unit projects RGB images of different brightness on the diffusion sheet based on the control instruction;

[0009] S3: The color analyzer obtains the RGB image through the ND filter, measures the color coordinates and brightness values ​​of the RGB images of different brightness at the current temperature, and then sends the color coordinates and brightness values ​​to the debugging device;

[0010] S4: The debugging device creates a brightness calibration point in the CIE Yxy color space, and calculates the RGB brightness contribution ratio under different brightness based on the brightness calibration point, the color coordinates, and the brightness value, wherein the RGB brightness contribution ratio includes the red light brightness contribution ratio, the green light brightness contribution ratio, and the blue light brightness contribution ratio;

[0011] S5: The debugging device calculates the white brightness value that can be achieved at each brightness calibration point based on the RGB brightness contribution ratio;

[0012] S6: the debugging device calculates the RGB current driving value at the current brightness according to the white brightness value, where the RGB current driving value includes a red light current driving value, a green light current driving value and a blue light current driving value;

[0013] S7: the debugging device generates a calibration data table based on the temperature, RGB current driving value, brightness value and color coordinates, and sends it to the HUD control board;

[0014] S8: The HUD control board receives and stores the calibration data table; the color analyzer can analyze the color coordinates and brightness values ​​of the RGB image at the current temperature, and then the debugging device can obtain it. At this time, the color coordinates and brightness values ​​will have deviations due to different temperatures and luminous efficiency. Therefore, a brightness calibration point is created through the debugging device, and the white brightness value can be calculated through the brightness calibration point, color coordinates and brightness value, so as to obtain the RGB current drive value. Since the RGB current drive value includes the red light current drive value, the green light current drive value and the blue light current drive value, the white balance calibration of the RGB image at the current temperature is achieved when the RGB current drive value is obtained. Since the above steps can be performed at different temperatures and different image imaging units can be replaced, the above method can solve the problem of luminous efficiency differences and inconsistent color temperature caused by installation differences and differences in the BIN values ​​of the three-color LED light source, and can solve the problem of color temperature deviation of the three-color LED light source under different ambient temperature conditions, thereby causing the color temperature deviation of the mixed white light.

[0015] Optionally, the color coordinates include red color coordinates, green color coordinates, and blue color coordinates; wherein x R The horizontal axis represents the red chromaticity, y R The ordinate represents the red chromaticity, x G The horizontal axis represents the green chromaticity, y G The ordinate represents the green chromaticity, x B The horizontal axis represents the blue chromaticity, yB The ordinate represents the blue chromaticity; the color coordinate and brightness value are expressed as, x W Represents the chromaticity horizontal coordinate of the RGB image, y W Represents the chromaticity ordinate of the RGB image.

[0016] Optionally, the expression of the brightness calibration point is:

[0017] X R +X G +X B =X W

[0018] Y R +Y G +Y B =Y W

[0019] Z R +Z G +Z B =Z W

[0020] Among them, X R Represents the brightness component of red on the X-axis, X G Represents the brightness component of green on the X axis, X B Represents the brightness component of blue on the X axis; Y R Represents the brightness component of red on the Y axis, Y G Represents the brightness component of green on the Y axis, Y B Represents the brightness component of blue on the Y axis; Z R Represents the brightness component of red on the Z axis, Z G Represents the brightness component of green on the Z axis, Z B Represents the brightness component of blue on the Z axis; X W , Y W and Z W Represent the X, Y, and Z values ​​of the CIE XYZ color coordinates respectively.

[0021] Optionally, the calculation formula of the RGB brightness contribution ratio is:

[0022]

[0023] Among them, Y R :Y G :Y B It is the contribution ratio of red light brightness, the contribution ratio of green light brightness and the contribution ratio of blue light brightness.

[0024] Optionally, the step S4 further includes: generating a color temperature calibration table, wherein the horizontal header of the color temperature calibration table is temperature, the vertical header is brightness, and the cells contain RGB brightness contribution ratios.

[0025] Optionally, the step S5 includes: the debugging device calculates the minimum brightness value and the maximum brightness value of the red light, the green light and the blue light respectively, and takes the minimum brightness value as the minimum and the maximum brightness value as the maximum to obtain the white brightness value.

[0026] Optionally, the calibration data table includes temperature, RGB current driving value, brightness value, and color coordinates.

[0027] Optionally, the debugging device is a computer.

[0028] In a second aspect, the present invention provides a white balance debugging system based on LCOS display technology, comprising: a HUD control board, an image imaging unit, a diffuser, an ND filter, a color analyzer, and a debugging device;

[0029] The HUD control board, image imaging unit, diffuser, ND filter and color analyzer are located in a straight line, the imaging direction of the image imaging unit is perpendicular to the diffuser, the diffuser and the ND filter are parallel, the working end of the color analyzer is toward the ND filter, the HUD control board and the image imaging unit are electrically connected, and the HUD control board and the color analyzer are electrically connected to the debugging equipment respectively.

[0030] Optionally, the white balance debugging system based on LCOS display technology also includes a fixed base, and the HUD control board, image imaging unit, diffuser, ND filter, and color analyzer are arranged on the fixed base.

[0031] In summary, the present invention at least includes the following beneficial technical effects:

[0032] 1. The white balance debugging method based on LCOS display technology can solve the problem of different luminous efficiency and inconsistent color temperature caused by installation differences and differences in the BIN values ​​of the three-color LED light sources, and can also solve the problem of color temperature shift of the three-color LED light sources under different ambient temperature conditions, which in turn causes color temperature shift of the mixed white light.

[0033] 2. The white balance debugging system based on LCOS display technology can effectively realize white balance calibration, ensure the color accuracy and consistency of the LCOS display, thereby improving the display effect and driving experience of the HUD system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of a white balance debugging system based on LCOS display technology in an embodiment of the present invention.

[0035] Figure 2 Schematic diagram of the implementation of the white balance debugging system based on LCOS display technology in an embodiment of the present invention.

[0036] Figure 3 It is a flowchart of a white balance debugging method based on LCOS display technology in an embodiment of the present invention.

[0037] Figure 4 Schematic diagram of brightness calibration points in CIEYxy color space.

[0038] Explanation of the reference numerals: 1. fixed base; 2. HUD control board; 3. image forming unit; 4. diffusion sheet; 5. ND filter; 6. color analyzer. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0040] The terms used in the following embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to be used as limitations of the present invention. As used in the specification of the present invention and the appended claims, the singular expressions "one", "a kind of", "said", "above", "the" and "this" are intended to also include plural expressions, unless there is a clear contrary indication in its context. It should also be understood that the term "and / or" used in the present invention refers to and includes any or all possible combinations of one or more listed items. The term "exemplary" means "used as an example, embodiment or illustrative", and any embodiment described as "exemplary" here does not have to be interpreted as being superior to or better than other embodiments. The terms "first" and "second" are only used for descriptive purposes, and cannot be understood as implying or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" can expressly or implicitly include one or more of these features, and in the description of the embodiments of the present invention, unless otherwise specified, the meaning of "multiple" is two or more.

[0041] The embodiment of the present invention provides a white balance debugging system based on LCOS display technology.

[0042] refer to Figure 1 and Figure 2A white balance debugging system based on LCOS display technology includes: a fixed base 1, a HUD control board 2, an image generation unit 3 (Picture Generation Unit, PGU), a diffuser 4 (Diffuser), an ND filter 5 (ND Filter, neutral gray filter), a color analyzer 6 and a computer.

[0043] The fixed base 1 is in the shape of a long strip and is arranged horizontally. The HUD control board 2, the image imaging unit 3, the diffuser 4, the ND filter 5 and the color analyzer 6 are sequentially installed on the fixed base 1, and the HUD control board 2, the image imaging unit 3, the diffuser 4, the ND filter 5 and the color analyzer 6 are located in a straight line, the imaging direction of the image imaging unit 3 is vertically toward the diffuser, the diffuser 4 and the ND filter 5 are parallel, and the working end of the color analyzer 6 is toward the ND filter 5. The HUD control board 2 and the image imaging unit 3 are electrically connected, and the HUD control board 2 and the color analyzer 6 are respectively electrically connected to the debugging device, and the debugging device is installed with white balance debugging software.

[0044] The HUD control board 2 adopts a PCBA board, which has a memory for processing and electrical connection with a processor, and has communication, storage and control functions. The image imaging unit 3 adopts an LCOS pixel imaging unit, and the color analyzer 6 adopts a CA410 model.

[0045] The debugging device is electrically connected to the HUD control board 2 via a USB cable or an HDMI cable, the debugging device is electrically connected to the color analyzer 6 via a USB cable, and the image imaging unit 3 is electrically connected to the HUD control board 2 via an FPC (Flexible Printed Circuit) cable.

[0046] In an embodiment of the present application, the debugging device adopts a computer, which includes a host, a display screen, a keyboard, a mouse and other external devices electrically connected to the host, and the host includes a main board, a CPU, a memory, a graphics card, a hard disk, a power supply and other modules respectively arranged on the main board. Each module is connected through a system bus and is connected to the external device through various interfaces.

[0047] When debugging the white balance, the staff opens the white balance debugging software in the computer, and controls the HUD control board 2 to issue control instructions through the white balance debugging software. The image imaging unit 3 can receive the control instructions and perform image imaging on the diffuser 4 based on the control instructions. At this time, the diffuser 4 can provide a uniform surface light source image. After that, the surface light source image passes through the ND filter 5 to achieve image brightness attenuation, so that the image brightness does not exceed the range of the color analyzer 6. The surface light source image after image brightness attenuation is then received and analyzed by the working end of the color analyzer 6. Finally, the color analyzer 6 sends the analysis results to the computer, and the staff performs calculations based on the analysis results to perform white balance calibration on the HUD control board 2, thereby ensuring the color accuracy and consistency of the LCOS display, thereby improving the display effect and driving experience of the HUD system.

[0048] The embodiment of the present invention also provides a white balance debugging method based on LCOS display technology.

[0049] refer to Figure 3 , a white balance debugging method based on LCOS display technology, comprising the following steps:

[0050] S1: The debugging device controls the HUD control board 2 to send a control instruction to the image imaging unit 3.

[0051] The debugging device is installed with white balance debugging software, and the debugging device can control the HUD control board 2 to send control instructions to the image imaging unit 3 through the white balance debugging software, so that the image imaging unit 3 works according to the control instructions.

[0052] The debugging device can be various forms of computers, such as tablet computers, laptop computers, and desktop computers.

[0053] S2: The image forming unit 3 projects an RGB image with different brightness on the diffusion sheet 4 based on the control instruction.

[0054] After acquiring the control instruction, the image forming unit 3 works according to the control instruction, thereby projecting an RGB image (image forming) on ​​the diffuser 4. At this time, the diffuser 4 can provide a uniform surface light source image. It should be understood that RGB images of different brightness are generated by multiple projections of the image forming unit 3, and the image forming unit 3 only projects an RGB image of one brightness each time.

[0055] S3: The color analyzer 6 obtains the RGB image passing through the ND filter 5, measures the color coordinates and brightness values ​​of the RGB image with different brightness at the current temperature, and then sends the color coordinates and brightness values ​​to the debugging device.

[0056] The surface light source image is passed through the ND filter 5 to achieve image brightness attenuation, so that the image brightness does not exceed the range of the color analyzer 6. Specifically, if the maximum driving current of the image imaging unit 3 is 6A, and the current driving accuracy of the hardware driver is 0.8mA, the maximum current driving value of the RGB image is 6A / 0.8mA=7500. In order to prevent the image imaging unit 3 from working in an extreme state for a long time, the current driving value is limited to 7000. Therefore, we can divide the brightness level into 7 brightness test points of 100, 200, 500, 1000, 2000, 5000, and 7000.

[0057] The color analyzer 6 obtains the RGB image (i.e., the surface light source image after the image brightness is attenuated) through the ND filter 5, and then the color coordinates and brightness values ​​of the RGB image at the current temperature can be directly measured. The color coordinates and brightness values ​​at the current temperature are a set of data. When the temperature changes, another set of data can be obtained. When the brightness changes, another set of data can be obtained. Different data groups are obtained by the color analyzer 6 obtaining RGB images under different conditions. Finally, the color analyzer 6 can send the color coordinates and brightness values ​​to the debugging device.

[0058] The color coordinates include the red chromaticity coordinate (x R ,y R ), green chromaticity coordinates (x G ,y G ), blue chromaticity coordinates (x B ,y B ). R The horizontal axis represents the red chromaticity, y R The ordinate represents the red chromaticity, x G The horizontal axis represents the green chromaticity, y G The ordinate represents the green chromaticity, x B The horizontal axis represents the blue chromaticity, y B The ordinate represents the chromaticity of blue. The above coordinates are coordinates in the CIEYxy color space (CIE 1931 Yxy color space).

[0059] The brightness value and color coordinates are expressed as (Y W , x W ,y W ), x W Represents the chromaticity horizontal coordinate of the RGB image, y W Represents the chromaticity ordinate of the RGB image.

[0060] In the embodiment of the present application, the current temperature may be -35°C, -15°C, 5°C, 25°C, 45°C, 65°C, or 85°C. The brightness value may be 50 cd / m 2 、100cd / m 2, 200cd / m 2 , 500cd / m 2 , 1000cd / m 2 、2000cd / m 2 , 5000cd / m 2 、10000cd / m 2 , 20000cd / m 2 , 50000cd / m 2 , 70000cd / m 2 (Affected by the above current driving value) It should be understood that the above temperature and brightness values ​​are only examples, and other values ​​of temperature and brightness may also be used. According to the above temperature and brightness values, a color temperature calibration table can be designed.

[0061] Specifically, the goal of this application is to calibrate an RGB image to a desired white point (a color coordinate) that can be converted to an x, y coordinate pair in the CIE Yxy color space, which is derived from the CIE XYZ color space.

[0062] When converting CIE Yxy color space to CIE XYZ color space:

[0063] Y=Y

[0064] x=X(X+Y+Z)

[0065] y=Y(X+Y+Z)

[0066] When converting CIE XYZ color space to CIE Yxy color space:

[0067]

[0068] Y=Y

[0069]

[0070] S4: The debugging device creates a brightness calibration point in the CIEYxy color space, and calculates the RGB brightness contribution ratio under different brightness based on the brightness calibration point, color coordinates, and brightness value. The RGB brightness contribution ratio includes the red light brightness contribution ratio, the green light brightness contribution ratio, and the blue light brightness contribution ratio.

[0071] refer to Figure 4 , the debugging device creates a brightness calibration point in the CIE Yxy color space on the white balance debugging software, and the brightness calibration point is a white point.

[0072] Specifically, the red, green, and blue brightness balance is calculated based on the red, green, and blue chromaticities and any desired brightness calibration points. The following system of equations uses linear XYZ space to additively combine the red, green, and blue components to create an output CIE XYZ color coordinate. This allows merging RGB to create an output brightness calibration point (W):

[0073] X R +X G +X B =X W

[0074] Y R +Y G +Y B =Y W

[0075] Z R +Z G +Z B =Z W

[0076] Among them, X R Represents the brightness component of red on the X-axis, X G Represents the brightness component of green on the X axis, X B Represents the brightness component of blue on the X axis; Y R Represents the brightness component of red on the Y axis, Y G Represents the brightness component of green on the Y axis, Y B Represents the brightness component of blue on the Y axis; Z R Represents the brightness component of red on the Z axis, Z G Represents the brightness component of green on the Z axis, Z B Represents the brightness component of blue on the Z axis; X W , Y W and Z W Represent the X, Y, and Z values ​​of the CIE XYZ color coordinates respectively.

[0077] From the above equations we can derive the following equation matrix to solve for the required brightness of each color:

[0078]

[0079] Among them, the red chromaticity coordinate (x R ,y R ), green chromaticity coordinates (x G ,y G ), blue chromaticity coordinates (x B ,y B ), brightness value and color coordinates (YW ， xW ,y W ) has been obtained in step S3, so the red light brightness Y can be obtained R , green light brightness Y G , blue light brightness Y B , that is, calculate the RGB brightness contribution ratio under different brightness (red light brightness Y R : Green light brightness Y G : Blue light brightness Y B ), the RGB brightness contribution ratio includes the red light brightness contribution ratio, the green light brightness contribution ratio and the blue light brightness contribution ratio.

[0080] It should be understood that if the target brightness Y W If set to 1, the brightness of R, G, and B will become percentages that sum to 1, and these R, G, and B brightnesses will scale linearly as the target brightness changes.

[0081] For example, assuming that the required brightness calibration point is (0.3127, 0.3290), the theoretical brightness that can be achieved with current drive values ​​of 1000 (0.8A) and 2000 (1.6A) is 932.011cd / m 2 and 1759.848cd / m 2 (A 4-fold attenuation was used during the measurement.) However, to achieve the color coordinates of (0.3127, 0.3290), the color coordinates of the measured current drive values ​​of 1000 and 2000 and the target color coordinates need to be substituted into the derived equation to obtain:

[0082]

[0083]

[0084] The calculation results show that the ratio of the two is very small, so in the actual implementation process, the average of the two is taken as the RGB brightness contribution ratio of this section. This is done because: the color coordinate offset of adjacent brightness levels at the same temperature is less than 0.02; the current drive value between 1000 and 2000 needs to be interpolated, and a unified calculation reference value is required.

[0085] So the final RGB brightness contribution ratio is:

[0086]

[0087] After obtaining the RGB brightness contribution ratio, a color temperature calibration table can be generated to correct and compensate the HUD through the changes in color temperature and brightness to achieve the expected target brightness and chromaticity. The horizontal header of the color temperature calibration table is temperature, and the vertical header of the color temperature calibration table is brightness. The content in each horizontal and vertical corresponding cell is the RGB brightness contribution ratio.

[0088] S5: The debugging device calculates the achievable white brightness value for each brightness calibration point based on the RGB brightness contribution ratio.

[0089] The debugging device can obtain the white brightness value of the mixed brightness calibration point (white point, ie, target color coordinate) based on the current driving value mixing ratio obtained in the above step S4.

[0090] The achievable brightness range is calculated based on the red LED:

[0091] W min1 =155.07 / 0.2169885≈714

[0092] W max1 =297.27 / 0.2169885≈1370

[0093] Among them, W min1 Represents the minimum brightness of red light, W max1 Represents the maximum value of red light brightness. The minimum value of red light brightness is: the red light brightness of the minimum current drive value (1000) divided by the red light brightness contribution ratio. The maximum value of red light brightness is: the red light brightness of the maximum current drive value (2000) divided by the red light brightness contribution ratio.

[0094] The achievable brightness range is calculated based on the green LED:

[0095] W min2 =740.19 / 0.75230817≈981

[0096] W max2 =1396.4 / 0.75230817≈1856

[0097] Among them, W min2 Represents the minimum brightness of green light, W max2 Represents the maximum green light brightness. The minimum green light brightness is: the green light brightness of the minimum current drive value (1000) divided by the green light brightness contribution ratio. The maximum green light brightness is: the green light brightness of the maximum current drive value (2000) divided by the green light brightness contribution ratio.

[0098] The achievable brightness range is calculated based on the blue LED:

[0099] W min3=36.751 / 0.03075293≈1195

[0100] W max3 =66.178 / 0.03075293≈2152

[0101] Among them, W min3 Represents the minimum brightness of blue light, W max3 Represents the maximum value of blue light brightness. The minimum value of blue light brightness is: the blue light brightness of the minimum current drive value (1000) divided by the blue light brightness contribution ratio. The maximum value of blue light brightness is: the blue light brightness of the maximum current drive value (2000) divided by the blue light brightness contribution ratio.

[0102] After respectively calculating the minimum red brightness, the maximum red brightness, the minimum green brightness, the maximum green brightness, the minimum blue brightness and the maximum blue brightness, the minimum of the above calculation results is taken as the maximum, and the maximum is taken as the minimum. Therefore, the achievable brightness range between 1000 and 2000 is 1195~1370cd / m 2 , that is, the white brightness value is 1195~1370cd / m 2 .

[0103] S6: The debugging device calculates the RGB current driving value at the current brightness according to the white brightness value, and the RGB current driving value includes a red light current driving value, a green light current driving value, and a blue light current driving value.

[0104] Suppose now we want to achieve 1200cd / m 2 The white brightness value can be calculated through the RGB brightness contribution ratio to get R=260.32, G=902.77, B=36.90. Combining the brightness coordinates corresponding to the three colors R, G, and B, linear interpolation can be performed to obtain the current driving values ​​of R, G, and B, which are 1740, 1248, and 1005 respectively. R, G, and B represent red light, green light, and blue light respectively.

[0105] S7: The debugging device generates a calibration data table based on the temperature, RGB current driving value, brightness and color coordinates, and sends it to the HUD control board 2.

[0106] The debugging device can achieve the brightness value and color coordinates of the HUD system by controlling the mixing ratio of the RGB current drive value (the mixing ratio of the R, G, B current drive values) at different temperatures. Therefore, the calibration data table contains: temperature, RGB current drive value, brightness value, and color coordinates. It should be understood that the brightness value and color coordinates include various components, which will not be repeated here. After generating the calibration data table, the debugging device sends the calibration data table to the HUD control board 2.

[0107] S8: The HUD control board 2 receives and stores the calibration data table.

[0108] After the debugging device sends the calibration data table to the HUD control board 2, the HUD control board 2 receives the calibration data table and stores it in the memory for subsequent HUD use.

[0109] In the above process, the problem of different luminous efficiency and inconsistent color temperature caused by installation differences and differences in BIN values ​​(brightness) of the three-color LED light source is solved, and the problem of color temperature shift of the three-color LED light source under different ambient temperature conditions, which leads to color temperature shift of the mixed white light, is solved. In addition, the white balance adjustment system can achieve any white light chromaticity between 2700K and 6500K, and the color coordinate error is less than 0.02.

[0110] As described above, the above embodiments are only used to introduce the technical solution of the present invention in detail, but the description of the above embodiments is only used to help understand the method and core idea of ​​the present invention and should not be understood as limiting the present invention. Changes or substitutions that can be easily thought of by technicians in this technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A white balance debugging method based on LCOS display technology, characterized in that: The following steps are involved: S1: The debugging device controls the HUD control board (2) to send a control instruction to the image forming unit (3); S2: the image forming unit (3) projects RGB images of different brightness onto the diffusion sheet (4) based on the control instruction; S3: The color analyzer (6) obtains the RGB image through the ND filter (5), measures the color coordinates and brightness values ​​of the RGB images of different brightness at the current temperature, and then sends the color coordinates and brightness values ​​to the debugging device; S4: The debugging device creates a brightness calibration point in the CIE Yxy color space, and calculates the RGB brightness contribution ratio under different brightness based on the brightness calibration point, the color coordinates, and the brightness value, wherein the RGB brightness contribution ratio includes the red light brightness contribution ratio, the green light brightness contribution ratio, and the blue light brightness contribution ratio; S5: The debugging device calculates the white brightness value that can be achieved at each brightness calibration point based on the RGB brightness contribution ratio; S6: the debugging device calculates the RGB current driving value at the current brightness according to the white brightness value, where the RGB current driving value includes a red light current driving value, a green light current driving value and a blue light current driving value; S7: the debugging device generates a calibration data table based on the temperature, RGB current driving value, brightness value and color coordinates, and sends it to the HUD control board (2); S8: The HUD control board (2) receives and stores the calibration data table.

2. A white balance debugging method based on LCOS display technology as claimed in claim 1, characterized in that: The color coordinates include the red chromaticity coordinate (x R ,y R ), green chromaticity coordinates (x G ,y G ), blue chromaticity coordinates (x B ,y B ), where x R The horizontal axis represents the red chromaticity, y R The ordinate represents the red chromaticity, x G The horizontal axis represents the green chromaticity, y G The ordinate represents the green chromaticity, x B The horizontal axis represents the blue chromaticity, y B The ordinate represents the blue chromaticity; the color coordinate and brightness value are expressed as (Y Q , x Q ,Y Q ), x W Represents the chromaticity horizontal coordinate of the RGB image, Y Q Represents the chromaticity ordinate of the RGB image.

3. A white balance debugging method based on LCOS display technology as claimed in claim 2, characterized in that: The expression of the brightness calibration point is: X R +X G +X B =X W AND R +Y G +Y B =And W WITH R +Z G +Z B =Z W Among them, X R Represents the brightness component of red on the X-axis, X G Represents the brightness component of green on the X axis, X B Represents the brightness component of blue on the X axis; Y R Represents the brightness component of red on the Y axis, Y G Represents the brightness component of green on the Y axis, Y B Represents the brightness component of blue on the Y axis; Z R Represents the brightness component of red on the Z axis, Z G Represents the brightness component of green on the Z axis, Z B Represents the brightness component of blue on the Z axis; X Q , Y Q and Z Q Represent the X, Y, and Z values ​​of the CIE XYZ color coordinates respectively.

4. A white balance debugging method based on LCOS display technology as claimed in claim 3, characterized in that: The calculation formula of the RGB brightness contribution ratio is: Among them, Y G : Y G : Y B It is the contribution ratio of red light brightness, the contribution ratio of green light brightness and the contribution ratio of blue light brightness.

5. A white balance debugging method based on LCOS display technology as claimed in claim 4, characterized in that: The step S4 further includes: generating a color temperature calibration table, wherein the horizontal table header of the color temperature calibration table is temperature, the vertical table header is brightness, and the cells are RGB brightness contribution ratios.

6. A white balance debugging method based on LCOS display technology as claimed in claim 4, characterized in that: The step S5 comprises: the debugging device calculates the minimum brightness value and the maximum brightness value of the red light, the green light and the blue light respectively, and takes the minimum brightness value as the minimum and the maximum brightness value as the maximum to obtain the white brightness value.

7. A white balance debugging method based on LCOS display technology as claimed in claim 1, characterized in that: The calibration data table includes temperature, RGB current driving value, brightness value, and color coordinates.

8. A white balance debugging method based on LCOS display technology as claimed in claim 1, characterized in that: The debugging device adopts a computer.

9. A white balance debugging system based on LCOS display technology for implementing a white balance debugging method based on LCOS display technology as claimed in any one of claims 1 to 8, characterized in that: include: HUD control board (2), image forming unit (3), diffusion sheet (4), ND filter (5), color analyzer (6) and debugging equipment; The HUD control board (2), the image forming unit (3), the diffuser (4), the ND filter (5) and the color analyzer (6) are located in a straight line, the imaging direction of the image forming unit (3) is perpendicular to the diffuser, the diffuser (4) and the ND filter (5) are parallel, the working end of the color analyzer (6) is facing the ND filter (5), the HUD control board (2) and the image forming unit (3) are electrically connected, and the HUD control board (2) and the color analyzer (6) are respectively electrically connected to the debugging equipment.

10. A white balance debugging system based on LCOS display technology as claimed in claim 9, characterized in that: It also comprises a fixed base (1), on which the HUD control panel (2), the image forming unit (3), the diffusion sheet (4), the ND filter (5), and the color analyzer (6) are arranged.

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