Method for realizing color temperature matching based on LED with four primary colors of red light, green light, blue light and white light

Abstract

The invention discloses a method for realizing color temperature matching based on LEDs with four primary colors of red light, green light, blue light and white light. The method comprises the following steps: respectively obtaining photometric and colorimetric performance parameters of a white temperature light source and a red light source, a green light source and a blue light source; calculating a tristimulus value corresponding to each single light source; obtaining a color mixing equation set according to a color addition principle; a PWM signal or an I2C signal is used for dimming; calculating an actual output luminous flux array of each single light source according to each color temperature point in the black body curve; calculating the maximum luminous flux of each single light source; according to the light mixing mathematical module, an upper computer is built, and the maximum luminous flux of the single light source of each color temperature point in the black body curve and the maximum luminous flux after light mixing are output. According to the method, the maximum luminous flux of the white light, the green light, the red light and the blue light and the maximum luminous flux after light mixing are obtained by establishing the light mixing mathematical model of the white light, the red light, the green light and the blue light, and accurate adjustment of the color temperature along with the color temperature blackbody curve is achieved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of light mixing, and particularly relates to a method for realizing color temperature proportioning based on red, green, blue and white light four-primary-color LEDs. BACKGROUND

[0002] With the gradual development of LED lighting, LED lamps have been widely applied to indoor and outdoor lighting fields in China, and have replaced traditional lighting devices such as incandescent lamps and fluorescent lamps, becoming the representatives of energy-saving, environment-friendly and intelligent lighting. Among them, the development advantage of intelligent lighting is very obvious, and combined with the inherent characteristics of LEDs, the emitted light can be better converged, so that the LED intelligent lamp becomes an important application in the field of LED lighting, and is widely used in supermarkets, homes, offices and landscapes, and has a promising market development prospect.

[0003] Now the intelligent lamp on the market has the functions of dimming and color adjusting, but there are disadvantages such as inaccurate color temperature dimming and low luminous flux in the actual use process. In order to control the cost, many manufacturers will adopt the way of mixing light of white light + red, green and blue lamp beads for design, and adjust the color temperature by combining the concept of color temperature blackbody curve and the concept of light health, but the actual color temperature adjustment cannot meet the needs of personalized lighting and high-end lighting of customers. SUMMARY

[0004] The purpose of the present application is to provide a method for realizing color temperature proportioning based on red, green, blue and white light four-primary-color LEDs, so as to solve the problems proposed in the background. The method for realizing color temperature proportioning based on red, green, blue and white light four-primary-color LEDs provided by the present application has the characteristics of realizing accurate color temperature adjustment along the color temperature blackbody curve.

[0005] In order to achieve the above purpose, the present application provides the following technical scheme: a method for realizing color temperature proportioning based on red, green, blue and white light four-primary-color LEDs, comprising the following steps:

[0006] S1, obtaining the photometric and colorimetric performance parameters of white color temperature light sources and red, green and blue light sources respectively;

[0007] S2, calculating the corresponding tristimulus values of each single light source according to the photometric and colorimetric performance parameters of each single light source;

[0008] S3, according to the principle of color addition, that is, the tristimulus value of mixed light is equal to the sum of the tristimulus values of each single light source, a color mixing equation set is obtained;

[0009] S4, using PWM signals or I 2 C signals for dimming;

[0010] S5, calculating the actual output luminous flux array of each single light source according to each color temperature point in the blackbody curve;

[0011] S6, taking the maximum mixed light flux after mixing light of each color temperature point in the black body curve, calculating the maximum light flux of each single light source;

[0012] S7, according to the mixed light mathematical module, building an upper computer, outputting the maximum light flux of each single light source at each color temperature point in the black body curve and the maximum light flux after mixing light.

[0013] Further in the application, in S2, the formula for calculating the corresponding tristimulus value of the single color temperature light source is:

[0014]

[0015] Y = Φ;

[0016]

[0017] Wherein, X, Y and Z are the corresponding tristimulus values, (x, y) is the color coordinate of the light source; Φ is the light flux of the light source.

[0018] Further in the application, in S3, the mixed color equation set is:

[0019]

[0020] Combined with the calculation formula of the tristimulus value, it is obtained that:

[0021]

[0022]

[0023] Wherein, X mix =X1+X2+X3+X4; Y mix =Y1+Y2+Y3+Y4; Z mix =Z1+Z2+Z3+Z4; X mix , Y mix , Z mix are the tristimulus values after mixing light; X1, Y1, Z1 are the tristimulus values of the white color temperature light source; X2, Y2, Z2 are the tristimulus values of the green light source; X3, Y3, Z3 are the tristimulus values of the red light source, X4, Y4, Z4 are the tristimulus values of the blue light source; (x mix , y mix ) are the color temperature coordinate values in the black body curve; (x1, y1) are the coordinate values of the white color temperature light source, Φ1 is the maximum light flux of the white color temperature light source; (x2, y2) are the coordinate values of the green light source, Φ2 is the maximum light flux of the green light source; (x3, y3) are the coordinate values of the red light source, Φ3 is the maximum light flux of the red light source; (x4, y4) are the coordinate values of the blue light source, Φ4 is the maximum light flux of the blue light source.

[0024] Further in the present application, in S5, according to the blackbody curve color temperature coordinate value, assuming condition 1: K mix >K1, take K mix <K1, take Assuming condition 2: According to different precision levels, the values are enlarged or reduced in proportion; the arrays of the actual output luminous flux of white light , the actual output luminous flux of green light , the actual output luminous flux of red light , and the actual output luminous flux of blue light are calculated respectively; wherein, K mix is the color temperature point in the blackbody curve, and K1 is the color temperature of the white light source.

[0025] Further in the present application, in S6, according to Wherein, Φ mix is the luminous flux after mixing light; the Φ mix of each color temperature point in the blackbody curve takes the maximum value, and the maximum white light luminous flux , the maximum green light luminous flux , the maximum red light luminous flux , and the maximum blue light luminous flux

[0026] Compared with the prior art, the present application has the following beneficial effects:

[0027] 1. The present application establishes a mixed light mathematical model of white light, red, green and blue, obtains the maximum luminous flux of white light, green, red and blue and the maximum luminous flux after mixing light, and realizes the precise adjustment of the color temperature blackbody curve to the color temperature.

[0028] 2. The optical output after mixing light of the present application meets the color point distribution of the color temperature blackbody curve.

[0029] 3. The present application can directly output the maximum luminous flux after mixing light, and the mixing light precision is high. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is the flowchart of the present application. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0032] Please refer to Figure 1 The application provides the following technical solutions: a method for realizing color temperature proportioning based on red, green, blue and white light four-primary color LEDs, comprising the following steps:

[0033] S1, obtaining the photometric and chromaticity performance parameters of a white color temperature light source and a red, green and blue light source respectively;

[0034] S2, calculating the corresponding tristimulus values of each single light source according to the photometric and chromaticity performance parameters of each single light source;

[0035] S3, obtaining a color mixing equation set according to the color addition principle, i.e. the tristimulus value of the mixed light is equal to the sum of the tristimulus values of each single light source;

[0036] S4, using a PWM signal or an I 2 C signal to perform dimming;

[0037] S5, calculating the actual output luminous flux array of each single light source according to each color temperature point in the black body curve;

[0038] S6, calculating the maximum luminous flux of each single light source by taking the maximum mixed light luminous flux after mixing light of each color temperature point in the black body curve;

[0039] S7, building an upper computer according to the light mixing mathematical module, and outputting the maximum luminous flux of each single light source and the maximum luminous flux after mixing light of each color temperature point in the black body curve.

[0040] Specifically, in S2, the formula for calculating the tristimulus value corresponding to the single color temperature light source is:

[0041]

[0042] Y=Φ;

[0043]

[0044] Wherein, X, Y and Z are the corresponding tristimulus values, (x, y) is the color coordinate of the light source; and Φ is the luminous flux of the light source.

[0045] Specifically, in S3, the color mixing equation set is:

[0046]

[0047] Combined with the calculation formula of the tristimulus value, it is obtained that:

[0048]

[0049] Wherein, X mix =X1+X2+X3+X4;Y mix =Y1+Y2+Y3+Y4;Z mix=Z1+Z2+Z3+Z4;;X mix Y mix Z mix X1, Y1, and Z1 are the tristimulus values ​​after light mixing; X2, Y2, and Z2 are the tristimulus values ​​of a white warm light source; X3, Y3, and Z3 are the tristimulus values ​​of a red light source; and X4, Y4, and Z4 are the tristimulus values ​​of a blue light source. mix y mix (x1, y1) represents the color temperature coordinates of the blackbody curve; (x2, y2) represents the coordinates of the white warm light source, and Φ1 represents the maximum luminous flux of the white warm light source; (x2, y2) represents the coordinates of the green light source, and Φ2 represents the maximum luminous flux of the green light source; (x3, y3) represents the coordinates of the red light source, and Φ3 represents the maximum luminous flux of the red light source; (x4, y4) represents the coordinates of the blue light source, and Φ4 represents the maximum luminous flux of the blue light source.

[0050] Specifically, in S5, based on the color temperature coordinates of the blackbody curve, assumption 1: K mix >K1, take K mix <K1, take Assumption 2: Values ​​are scaled up or down proportionally according to different accuracy levels; the actual output luminous flux of the white temperature is calculated respectively. The array; actual output luminous flux of the green light source Array of red light sources; actual output luminous flux of red light sources The array; actual output luminous flux of the blue light source An array; where K mix K1 represents the color temperature point in the blackbody curve, and K1 is the color temperature of a white warm light source.

[0051] Specifically, in S6, according to Where, Φ mix The luminous flux after light mixing; Φ at each color temperature point in the blackbody curve. mix Take the maximum value and calculate the maximum white light luminous flux. Maximum green light luminous flux Maximum red light luminous flux Maximum blue light luminous flux

[0052] Example 1

[0053] S1. According to the specifications, input the coordinates of the white warm light source (0.3818, 0.3797) and luminous flux of 300 lm; the coordinates of the green light source (0.1852, 0.7247) and luminous flux of 50 lm; the coordinates of the red light source (0.6989, 0.3010) and luminous flux of 40 lm; and the coordinates of the blue light source (0.1544, 0.0287) and luminous flux of 50 lm.

[0054] S2. Dimming adopts PWM dimming, and the white light dimming accuracy is 1% amplified value;

[0055] S3. Calculate the actual output luminous flux of white light, green light, red light, and blue light based on the color temperature coordinates of the blackbody curve;

[0056] S4. Based on the above light mixing mathematical module, build a host computer to output the maximum luminous flux of white light, green light, red light, and blue light, as well as the maximum luminous flux after light mixing.

[0057] The following table shows the output results of this embodiment:

[0058] Black body curve color temperature steps W_x coordinate W_y coordinate W_lumens G_x coordinate G_y coordinate G_lumens R / B_x coordinate value R / B_y coordinate value R / B_Y3 lumens Total output lumens Calculation form 2200 0.3818 0.3797 24 0.1852 0.7247 38.3015 0.6989 0.301 37.1367 99.4382 WGR 2500 0.3818 0.3797 42 0.1852 0.7247 43.5458 0.6989 0.301 39.5432 125.089 WGR 2700 0.3818 0.3797 72 0.1852 0.7247 46.5555 0.6989 0.301 39.8547 158.4102 WGR 3000 0.3818 0.3797 132 0.1852 0.7247 48.2673 0.6989 0.301 39.3253 219.5926 WGR 3500 0.3818 0.3797 300 0.1852 0.7247 43.2427 0.6989 0.301 34.4768 377.7195 WGR 4000 0.3818 0.3797 300 0 0 0 0 0 0 300 W 4500 0.3818 0.3797 300 0.1852 0.7247 17.6083 0.1544 0.0287 1.6774 319.2857 WGB 5000 0.3818 0.3797 300 0.1852 0.7247 34.964 0.1544 0.0287 3.2602 338.2242 WGB 5700 0.3818 0.3797 291 0.1852 0.7247 49.7199 0.1544 0.0287 5.0798 345.7997 WGB 6500 0.3818 0.3797 207 0.1852 0.7247 49.7745 0.1544 0.0287 5.3001 262.0746 WGB

[0059] In summary, this invention establishes a mathematical model for mixing white, red, green, and blue light, thereby obtaining the maximum luminous flux of each light source (white, green, red, and blue) and the maximum luminous flux after mixing. This achieves precise adjustment of color temperature based on the color temperature blackbody curve. The optical output after mixing conforms to the color point distribution of the color temperature blackbody curve. Furthermore, this invention can directly output the maximum luminous flux after mixing, demonstrating high mixing accuracy.

[0060] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for achieving color temperature matching based on red, green, blue, and white four-primary-color LEDs, characterized in that, Includes the following steps: S1. Obtain the photometric and colorimetric performance parameters of the white warm light source and the red-green-blue light source, respectively; S2. Calculate the tristimulus values ​​corresponding to each single light source based on the photometric and colorimetric performance parameters of each single light source. S3. According to the principle of color addition, that is, the tristimulus value of the mixed light is equal to the sum of the tristimulus values ​​of each individual light source, we can obtain the color mixing equations. S4, using PWM signal or I 2 Dimming is achieved using the C signal; S5. Calculate the actual output luminous flux array of each single light source based on each color temperature point in the blackbody curve; S6. Take the maximum mixed light flux of each color temperature point in the blackbody curve after mixing, and calculate the maximum light flux of each single light source. S7. Based on the light mixing mathematical module, build a host computer to output the maximum luminous flux of a single light source and the maximum luminous flux after light mixing at each color temperature point in the blackbody curve.

2. The method for achieving color temperature matching based on red, green, blue, and white four-primary-color LEDs according to claim 1, characterized in that: In step S1, the photometric and colorimetric performance parameters of the monochromatic temperature light source are obtained using an integrating sphere spectrometer or the light source specification sheet.

3. The method for achieving color temperature matching based on red, green, blue, and white four-primary-color LEDs according to claim 1, characterized in that: In S2, the formula for calculating the tristimulus values ​​corresponding to a monochromatic temperature light source is: Y = Φ; Where X, Y, and Z are the corresponding tristimulus values, (x, y) are the color coordinates of the light source, and Φ is the luminous flux of the light source.

4. The method for achieving color temperature matching based on red, green, blue, and white four-primary-color LEDs according to claim 3, characterized in that: In S3, the color mixing equations are: Based on the formula for calculating tristimulus values, we can derive: Among them, X mix =X1+X2+X3+X4; Y mix =Y1+Y2+Y3+Y4; Z mix =Z1+Z2+Z3+Z4;;X mix Y mix Z mix X1, Y1, and Z1 are the tristimulus values ​​after light mixing; X2, Y2, and Z2 are the tristimulus values ​​of a white warm light source; X3, Y3, and Z3 are the tristimulus values ​​of a red light source; and X4, Y4, and Z4 are the tristimulus values ​​of a blue light source. mix y mix (x1, y1) represents the color temperature coordinates of the blackbody curve; (x2, y2) represents the coordinates of the white warm light source, and Φ1 represents the maximum luminous flux of the white warm light source; (x2, y2) represents the coordinates of the green light source, and Φ2 represents the maximum luminous flux of the green light source; (x3, y3) represents the coordinates of the red light source, and Φ3 represents the maximum luminous flux of the red light source; (x4, y4) represents the coordinates of the blue light source, and Φ4 represents the maximum luminous flux of the blue light source.

5. The method for achieving color temperature matching based on red, green, blue, and white four-primary-color LEDs according to claim 1, characterized in that: In S5, based on the color temperature coordinates of the blackbody curve, assumption 1: K mix >K1, take K mix <K1, take Assumption 2: Values ​​are scaled up or down proportionally according to different accuracy levels; the actual output luminous flux of the white temperature is calculated respectively. The array; actual output luminous flux of the green light source Array of red light sources; actual output luminous flux of red light sources The array; actual output luminous flux of the blue light source An array; where K mix K1 represents the color temperature point in the blackbody curve, and K1 is the color temperature of a white warm light source.

6. The method for achieving color temperature matching based on red, green, blue, and white four-primary-color LEDs according to claim 1, characterized in that: In S6, according to Where, Φ mix The luminous flux after light mixing; Φ at each color temperature point in the blackbody curve. mix Take the maximum value and calculate the maximum white light luminous flux. Maximum green light luminous flux Maximum red light luminous flux Maximum blue light luminous flux

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