32-bit true color rendering method

Abstract

The application discloses a 32-color true color restoration method, and calculates 32 primary wavelength points based on given three primary color LEDs; calculates 32 primary wavelength intersection points according to the 32 primary wavelength points; calculates all primary wavelength color points corresponding to the 32 color points in a three color domain through color purity, wherein the three color domain is surrounded by the connecting lines RG, GB, BE and ER in a CIE chromaticity diagram, R, G and B are coordinate points of the given three primary color LEDs in the CIE chromaticity diagram, and E is an equal-energy center point of the CIE chromaticity diagram; and takes the primary wavelength color point with any color purity P E as a target color point to calculate the mixing proportion of the three primary color LEDs. The application quantitatively divides the given RGB three primary color three color domain into 32 primary wavelength colors, and quantitatively realizes the change of each primary wavelength color in the given three color domain through the concept of color purity, so that the required illumination color is quantitatively restored.

Description

Technical Field

[0001] This invention relates to the field of lighting technology, specifically a method for 32-color true color reproduction. Background Technology

[0002] In recent years, LEDs have been increasingly used in scene lighting, resulting in a richer variety of lighting scenes and modes. However, the shortcomings of scene lighting technology have also become more prominent. Typically, scene lighting uses RGB three-primary-color LEDs for color mixing. Traditional color mixing methods start from the RGB brightness gradient, setting the gradient level of the RGB three-primary-color LEDs to 255, and mixing various colors using duty cycles between 0 and 255 for each color. The resulting color is merely a simulation of different duty cycles. While it achieves rich color variations, it doesn't consider whether the lighting color truly reflects actual needs or provides a precise quantitative definition of the color result. Summary of the Invention

[0003] The purpose of this invention is to provide a 32-color true color reproduction method to solve the problems of existing technologies that use different duty cycles of RGB three primary colors to achieve various colors, without considering whether the lighting color is combined with actual needs and accurately reproduced, and without being able to accurately define the color result quantitatively.

[0004] The present invention solves the above problems through the following technical solution:

[0005] A method for restoring 32-color true color, comprising:

[0006] Step S100: Calculate 32 dominant wavelength points based on the given three-primary-color LEDs;

[0007] Step S200: Calculate the 32 main wavelength intersection points based on the 32 main wavelength points;

[0008] Step S300: Calculate all dominant wavelength color points corresponding to the 32 color points in the three-color domain by color purity. The three-color domain is enclosed by the lines RG, GB, BE and ER in the CIE chromaticity diagram. R, G and B are the coordinate points of the given three primary color LEDs in the CIE chromaticity diagram, and E is the isoenergetic center point of the CIE chromaticity diagram.

[0009] Step S400: Using any color purity P E Using the dominant wavelength color point as the target color point, the mixing ratio of the three primary color LEDs is calculated.

[0010] Step S100 specifically includes:

[0011] Step S110: Based on the coordinates R, G, and B of the given three primary color LED in the CIE chromaticity diagram and the isoenergetic center point E of the CIE1931 chromaticity diagram, connect RG, GB, BE, and ER to form the three role domains that the given three primary color LED can realize.

[0012] Step S120: Connect ER, EG, and EB respectively and extend them to the edge curve of the CIE chromaticity diagram. The intersection points are the main wavelengths of the three primary colors. Divide the main wavelengths of the three primary colors from the smallest to the largest into 32 main wavelength points at a set interval.

[0013] The specific steps of step S200 include: the line connecting the isoenergetic center point E and the 32 dominant wavelength points intersects the edge line RG or edge line GB of the three-color domain respectively, to obtain 32 dominant wavelength intersection points, which are the 32 most saturated color points of the three-color domain.

[0014] Step S300 specifically includes:

[0015] Step S310: Normalize the color purity of the three color domains. Taking the boundary color points of the three color domains as 100%, divide the intersection points of the isoenergetic center point E and the 32 dominant wavelengths into evenly divided intervals of 0-100% color purity according to a set interval, and perform the following steps:

[0016] Step S311: Select a dominant wavelength intersection point J(x) within the three-dimensional domain. J ,y J ), corresponding to any color purity P E The dominant wavelength color point P(x) P ,y P ):

[0017] x P =x J +(100%-P) E )×(x E -x J )

[0018] y P =y J +(100%-P) E )×(y E -y J )

[0019] Step S312: Repeat step S311 until traversing 32 main wavelength intersection points to obtain 32 main wavelength color points;

[0020] Step S320: Repeat steps S311-S312 until all color saturations P have been traversed. E We obtained the dominant wavelength color points corresponding to different color purities at the intersection points of the 32 dominant wavelengths.

[0021] Step S400 specifically includes:

[0022] Step S410: Take any color purity as P E Any dominant wavelength color point P(x) P ,y P Connect BP and extend the intersection line RG at M(x) M ,y M Then we have:

[0023]

[0024]

[0025] Where R1, G1, and B1 are the amounts of the three primary color LEDs, and M1 is the mixing amount of R1 and G1, M1 = R1 + G1. Substituting the coordinates, we obtain the color purity P. E The geometric blending ratio of the color points is R1:G1:B1;

[0026] Step S420, the conversion relationship between the three-primary-color LED mixing ratio and geometric ratio, optical parameters, and electrical parameters is as follows:

[0027]

[0028]

[0029] in, W represents the luminous flux of red light. R This refers to the red light radiation power. For green light luminous flux; W G The green light radiation power; Blue light luminous flux; W B This refers to the blue light radiation power. This is the ratio of red light energy efficiency; This is the ratio of green light energy efficiency; The ratio of blue light efficiency; y R y G y B Let y be the y-coordinate of the tri-color LED;

[0030] Step S430: Substitute the coordinates and geometric mixing ratios to obtain the three-primary-color LED mixing ratio R1':G1':B1';

[0031] Step S440: Repeat steps S410-S430 until all dominant wavelength color points are traversed, obtaining the color purity P of all dominant wavelength color points. E The color mixing ratio of the three primary color LEDs is R1':G1':B1';

[0032] Step S450: Repeat steps S410-S440 until all color purities are traversed, and the three-primary-color LED mixing ratio R1':G1':B1' of all primary wavelength color points under all color purities is obtained.

[0033] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0034] (1) The present invention quantitatively divides the given RGB three primary color three role domains into 32 dominant wavelength colors, and quantitatively realizes the change of each dominant wavelength color in the given three role domains through the concept of color purity, and quantitatively restores the required lighting color.

[0035] (2) This invention uses reverse derivation to target 32 ​​main wavelengths, gives the variation law in the three color domains, and calculates the three primary color mixing ratios of the 32 main wavelengths at each color purity based on the variation law, so as to achieve the purpose of scene lighting color restoration. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the three-color domain formed by the RGB three primary colors of the present invention;

[0037] Figure 2 This is a schematic diagram of the dominant wavelength of CIE chromaticity.

[0038] Figure 3 A schematic diagram of the intersection points of the 32 main wavelengths;

[0039] Figure 4 A schematic diagram of 32 dominant wavelength color points corresponding to 40% color purity;

[0040] Figure 5 This is a schematic diagram for calculating the RGB color mixing ratio. Detailed Implementation

[0041] The present invention will be further described in detail below with reference to embodiments, but the implementation of the present invention is not limited thereto.

[0042] Example:

[0043] A method for restoring 32-color true color, comprising:

[0044] I. Determine the boundary of 32 dominant wavelength points

[0045] Given an RGB LED with coordinates R(0.7000, 0.2993), G(0.1609, 0.7342), and B(0.1298, 0.0698) on the CIE chromaticity diagram, and the isoenergetic center E(0.3333, 0.3333) of the CIE chromaticity diagram, the area enclosed by lines RG, GB, BE, and ER represents the three-color domain that can be achieved by this RGB LED. Figure 1 As shown;

[0046] According to the CIE colorimetric principle, the isoenergetic center point is the CIE 1931 colorimetric value. Figure 3 The primary colors are equal-energy white light. For any color, the extension of the line connecting the center point of equal energy to that color intersects the edge curve of the CIE 1931 chromaticity diagram. The wavelength corresponding to this intersection point is the dominant wavelength of that color. Therefore, the dominant wavelengths of the RGB three primary colors are 625nm, 525nm, and 470nm. In the CIE chromaticity diagram, from 470nm to 625nm, there are 32 dominant wavelength points at 5nm intervals, such as... Figure 2 As shown;

[0047] II. Calculate the intersection points of the 32 principal wavelengths based on the 32 principal wavelength points.

[0048] The line connecting the isoenergetic center point E to the 32 principal wavelength points intersects the three-color domain boundaries RG and GB at 32 points. These 32 intersection points are the most saturated color points in the three-color domain. The 32 principal wavelength intersection points are as follows: Figure 3 As shown;

[0049] Detailed calculation process:

[0050] The intersection of the 32 main wavelengths can be calculated using the connecting function y = kx + b.

[0051] Let the dominant wavelength point be S(x) S y S ), the isoenergetic center point E(x) E ,y E The equation for the line connecting ES is:

[0052]

[0053] Similarly, let the RGB coordinates of the three-dimensional domain fixed point be divided into R(x) and R(x). R y R ), G(x G y G B(x) B y B Then the equation of the line connecting the three role domain boundaries RG and GB is:

[0054]

[0055]

[0056] The coordinates of the isoenergetic center point are E(0.3333, 0.3333), and RGB are the given three primary colors with coordinates R(0.7000, 0.2993), G(0.1609, 0.7342), and B(0.1298, 0.0698). Substituting these coordinates into formulas (1), (2), and (3), we obtain the formulas for connecting ES, RG, and GB.

[0057] ES Connection:

[0058]

[0059] RG connection:

[0060] y = -0.8067x + 0.8640 (5)

[0061] GB connection:

[0062] y = 21.3633x - 2.7032 (6)

[0063] Using formulas (4), (5), and (6), the 32 intersection points of the main wavelengths corresponding to ES and RG, and ES and GB, can be calculated respectively. In equation (4), x S y S For arbitrary dominant wavelength coordinates, the CIE chromaticity diagram in colorimetry is drawn based on the coordinates corresponding to each wavelength within the range of 380nm–780nm (as shown in Table 1). Therefore, the 32 dominant wavelengths between 470nm and 625nm are the defined coordinate points. Figure 3 As shown.

[0064] Table 1. CI E Chromaticity Diagram: Color Coordinates for 455nm-650nm

[0065]

[0066]

[0067] For ease of understanding and calculation, we take the 560nm main wavelength point as an example. The coordinates corresponding to 560nm can be found in Table 1 as (0.3731, 0.6245). Substituting these coordinates into equation (4), we get:

[0068] ES Connection:

[0069] y = 7.3153x - 2.1049 (7)

[0070] The dominant wavelength of 560nm is on one side of the RG edge, so by combining equations (5) and (7), we can obtain:

[0071] x=[0.8640-(-2.1049)]÷[7.3153-(-0.8067)]=0.3655

[0072] y=7.3153×0.3655-2.1049=0.5691

[0073] That is, the intersection point J(0.3655,0.5691) of the dominant wavelength with a dominant wavelength of 560nm on the boundary of the three-dimensional domain RG. According to the above method, the coordinates of the dominant wavelength intersection points corresponding to the 32 dominant wavelengths of the three-dimensional domain can be calculated. See Appendix Table 2 for details.

[0074] Table 2. Coordinates of the 32 color points at the boundary of the three-color domain and coordinates at 40% color purity.

[0075]

[0076]

[0077]

[0078] III. Calculation of 32-color purity

[0079] Color purity provides the total number of colors corresponding to the 32 hues within the three-role domain. According to the colorimetric definition, the color purity of a color point is the ratio of the distance from the isoenergetic center point to that color point to the distance from the isoenergetic center point to the dominant wavelength of that color. On the CIE colorimetric diagram, the color purity of the edge curves is 100%, and the color purity of the isoenergetic center is 0.

[0080] To facilitate the calculation of color point coordinates within the three-color domain, the color purity of the three-color domain is renormalized. The boundary color points of the three-color domain are set to 100%, and the line connecting the isoenergetic center point and the 32 color points represents the color purity from 0% to 100%. The range is divided evenly according to a set interval; that is, color purity is the unknown variable in this technology, denoted by P. E express.

[0081] Take any dominant wavelength point J(x) within the three role domains J ,y J ), corresponding to a certain color purity P E The color point (x) P ,y P The coordinates are:

[0082] x P =x J +(100%-P) E )×(x E -x J (8)

[0083] y P =y J +(100%-P)E )×(y E -y J (9)

[0084] In formulas (8) and (9), x E y E Let x be the coordinates of the isoenergetic center E (0.3333, 0.3333). J y J Given the coordinates of the intersection points of the three dominant wavelengths at the boundary of the three role domains, find the corresponding coordinate values ​​of the dominant wavelengths in Table 2. E It is a numerical variable, input from the outside.

[0085] For example, still taking the dominant wavelength of 560nm as an example, the coordinates of the chromatic point at 560nm on the boundary of the three color domains are J(0.3655, 0.5691). Assume that the color purity P needs to be calculated. E Substituting the coordinates of 40% of the color points into equations (8) and (9), we get:

[0086]

[0087]

[0088] That is, P E The coordinates of the color point when it is 40% are (0.3462, 0.4276).

[0089] Similarly, following the example above, all coordinates of the 32 color points at 40% color purity can be calculated, such as... Figure 4 As shown, the coordinates of 40% color purity are just one set of color points within the three color domains. They are only used here to show the changing trend of the 32 dominant wavelength color points within the three color domains, and also to facilitate the calculation of the mixing ratio of the RGB three primary colors in the next step. The coordinates of 40% color purity are detailed in Table 2.

[0090] Similarly, by changing the color purity and repeating the above steps, we can obtain the corresponding dominant wavelength color points for each dominant wavelength under different color purity.

[0091] IV. Calculation of the mixing ratio of RGB three primary color LEDs:

[0092] Based on the calculation results of the dominant wavelength and color purity above, the changes of each color in the RGB three-color domain are finally represented by the 32 dominant wavelength and its color purity P. E To quantify, P E Variations between 0% and 100% manifest as changes in color points across the three color domains. Therefore, different P... EThe dominant wavelength color point under color purity is used as the target color point. The method for calculating the RGB three-primary-color LED mixing ratio is based on invention patent ZL201711098700.9, entitled "Multi-channel LED Geometric Mixing Method". The details are as follows:

[0093] Let the purity of a certain color be P. E The dominant wavelength color point P(x) P ,y P Connect BP and extend it to intersect RG at M(x) M ,y M Then we have:

[0094] BP connection:

[0095]

[0096] For ease of calculation, we will still take the 40% color purity 560nm main wavelength from Chapter 2 as an example. From Table 2, we can find that the corresponding main wavelength color point is P(0.3462, 0.4276). Substituting it into B(0.1298, 0.0698), equation (10) simplifies to:

[0097] y = 1.6536x - 0.1448 (11)

[0098] By combining formulas (5) and (11), the intersection point M(x) of BP and RG can be calculated. M ,y M ):

[0099] x M = [0.8640 - (-0.1448)] ÷ [1.6536 - (-0.8067)] = 0.4100

[0100] y M =1.6536 × 0.4100 - 0.1448 = 0.5332

[0101] According to the color mixing principle of colorimetry, the color point M(x) M ,y M The color point P(x) is formed by mixing color points R(0.7000, 0.2993) and G(0.1609, 0.7342). P ,y P ) by color point M(x M ,y M If B(0.1298, 0.0698) is mixed with B(0.1298, 0.0698), then we have:

[0102]

[0103]

[0104] In formulas (10) and (11), R1, G1, and B1 are the quantities of the three primary color LEDs, and M1 is the mixing quantity of R1 and G1, where M1 = R1 + G1. Substituting the color points P(0.3462, 0.4276), M(0.4100, 0.5332) and the RGB three primary color coordinates into and transforming formulas (12) and (13), we get:

[0105]

[0106]

[0107] If G1 is set to 1, then R1:G1:B1 = 0.859:1:0.549. This ratio is the geometric mixing ratio of the given RGB three primary color LEDs to form a color point with a main wavelength of 560nm and a color purity of 40%. The actual power ratio needs to be calculated by combining the luminous efficacy of each color LED and the actual required brightness.

[0108] According to the "Multi-channel LED Geometric Mixing Method", the conversion relationship between the final three-primary-color LED mixing ratio R1':G1':B1' and the geometric ratio R1:G1:B1, optical parameters, and electrical parameters is as follows:

[0109]

[0110]

[0111] In the formula, —The ratio of light energy efficiency. W represents the luminous flux of red light. R This refers to the red light radiation power. For green light luminous flux; W G The green light radiation power; Blue light luminous flux; W B This refers to the blue light radiation power. This is the ratio of red light energy efficiency; This is the ratio of green light energy efficiency; This is the ratio of blue light efficiency. For a given LED, this ratio can be considered a constant, obtained through testing. The luminous efficiency ratios of the selected RGB three-color LEDs in this technology are 164.42, 485.24, and 75.15, respectively; R y G y B —The y-coordinates of RGB three-color LEDs. For a given RGB three-color LED, the y-coordinates can be considered constant. In this technology, the y-coordinates of the selected RGB three-color LEDs are 0.2993, 0.7342, and 0.0698, respectively.

[0112] Substituting the above data and geometric proportions into equations (15) and (16), we get:

[0113] R':G':B'=0.7140:1:0.8944 (17)

[0114] Equation (17) is the mixing ratio of the three primary colors with a main wavelength of 560nm and a color purity of 40%.

[0115] Similarly, following the example method described above, the mixing ratio of the three primary colors under different dominant wavelengths and color purities can be calculated. This ratio is based on green (G) being 1; regardless of which color is set to 1, the ratio will not change. This ratio can be directly converted into the driving current ratio of RGB three-primary-color LEDs.

[0116] Based on the CIE colorimetric principle, this invention innovatively divides the given RGB three primary color three role domains into 32 dominant wavelength colors using the concept of dominant wavelength, and further quantifies the changes of each dominant wavelength color within the given three role domains through the concept of color purity, thereby quantitatively restoring the required lighting color.

[0117] This invention, through reverse derivation, targets 32 dominant wavelengths, gives the variation law in the three color domains, and calculates the three primary color mixing ratios of the 32 dominant wavelengths at various color purities based on the variation law, thereby achieving the purpose of scene lighting color reproduction.

[0118] Although the present invention has been described herein with reference to illustrative embodiments, the above embodiments are merely preferred embodiments of the present invention, and the implementation of the present invention is not limited to the above embodiments. It should be understood that those skilled in the art can devise many other modifications and implementations, which will fall within the scope and spirit of the principles disclosed in this application.

Claims

1. A method for restoring 32-color true color, characterized in that, include: Step S100: Calculate 32 dominant wavelength points based on the given three-primary-color LEDs; Step S200: Calculate the 32 main wavelength intersection points based on the 32 main wavelength points; Step S300: Calculate all dominant wavelength color points corresponding to the 32 color points in the three-color domain by color purity. The three-color domain is enclosed by the lines RG, GB, BE and ER in the CIE chromaticity diagram. R, G and B are the coordinate points of the given three primary color LEDs in the CIE chromaticity diagram, and E is the isoenergetic center point of the CIE chromaticity diagram. Step S400: Using any color purity Using the dominant wavelength color point as the target color point, calculate the mixing ratio of the three primary color LEDs; Step S100 specifically includes: Step S110: Based on the coordinates R, G, and B of the given three primary color LED in the CIE chromaticity diagram and the isoenergetic center point E of the CIE1931 chromaticity diagram, connect RG, GB, BE, and ER to form the three role domains that the given three primary color LED can realize. Step S120: Connect ER, EG, and EB respectively and extend them to the edge curve of the CIE chromaticity diagram. The intersection points are the main wavelengths of the three primary colors. Divide the main wavelengths of the three primary colors from the smallest to the largest into 32 main wavelength points at a set interval. The specific steps of step S200 include: the line connecting the isoenergetic center point E and the 32 principal wavelength points intersects the edge line RG or edge line GB of the three-color domain respectively, to obtain 32 principal wavelength intersection points, which are the 32 most saturated color points of the three-color domain; Step S300 specifically includes: Step S310: Normalize the color purity of the three color domains. Taking the boundary color points of the three color domains as 100%, divide the intersection points of the isoenergetic center point E and the 32 dominant wavelengths into evenly divided intervals of 0-100% color purity according to a set interval, and perform the following steps: Step S311: Take a dominant wavelength intersection point J within the three-dimensional domain. , ), corresponding to any color purity The dominant wavelength color point P ( , ): ； ； Step S312: Repeat step S311 until traversing 32 main wavelength intersection points to obtain 32 main wavelength color points; Step S320: Repeat steps S311-S312 until all color saturations have been traversed. We obtained the dominant wavelength color points corresponding to different color purities at the intersection points of the 32 dominant wavelengths; Step S400 specifically includes: Step S410: Take any color with a purity of... Any dominant wavelength color point P(x) P ,y P Connect BP and extend the intersection line RG to M ( , Then we have: ； ； Where R1, G1, and B1 represent the amounts of the three primary color LEDs, and M1 represents the mixing amount of R1 and G1. Substituting the coordinates, we obtain the color purity. The geometric blending ratio of the color points is R1:G1:B1; Step S420, the conversion relationship between the three-primary-color LED mixing ratio and geometric ratio, optical parameters, and electrical parameters is as follows: ； ； in, For red light luminous flux; This refers to the red light radiation power. For green light luminous flux; The green light radiation power; Blue light luminous flux; This refers to the blue light radiation power. This is the ratio of red light energy efficiency; This is the ratio of green light energy efficiency; This is the ratio of blue light efficiency. , , Let y be the y-coordinate of the tri-color LED; Step S430: Substitute the coordinates and geometric mixing ratios to obtain the three-primary-color LED mixing ratios. : : ; Step S440: Repeat steps S410-S430 until all dominant wavelength color points have been traversed, obtaining the color purity of all dominant wavelength color points. Three-color LED mixing ratio : : ; Step S450: Repeat steps S410-S440 until all color saturations are traversed, obtaining the three-primary-color LED mixing ratios for all dominant wavelength color points under all color saturations. : : .

Images