Patent ID: 9018853
Filing Date: 2015-04-28
Classification: H05B

Abstract:
1. A method for calibrating a color LED light unit comprising at least first-, second-, and third-color LEDs, comprising: a) defining a target color on a color map to calibrate; b) selecting initial calibration coefficients associated with the target color; c) storing: 1) the initial, or 2) updated calibration coefficients in a non-volatile memory of the light unit; d) controlling the light unit with a controller to drive the LEDs to attempt to emit the target color, producing an attempted color, utilizing one of the initial and updated calibration coefficients; e) measuring the attempted color to determine if it matches the target color within a predefined tolerance; f) if the attempted color matches the target color, then terminating the method; g) if the attempted color does not match the target color, then performing the following; h.1) selecting a first color component; i.1 adapting at least one calibration coefficient associated with the selected first color component by a first color component first amount; j.1 a performing (c)-(g) again; h.2) selecting a second color component that is different from the first color component; i.2) adapting at least one calibration coefficient associated with the selected second color component by a second color component first amount; j.2) performing (c)-(g) again; h.3) selecting the first color component; i.3) adapting the at least one calibration coefficient associated with the selected first color component by a first color component second amount that is smaller than the first color component first amount and avoids an overshoot of the target color; i.3) performing (c)-(g) again; h.4) selecting the second color component; i.4) adapting the at least one calibration coefficient associated with the selected second color component by a second color component second amount that is smaller than the second color component first amount and avoids an overshoot of the target color; j.4) performing (c)-(g) again; wherein a path in a color space of the attempted colors forms: a) a converging winding path when only two color components are utilized; and b) a converging spiral when three color components are utilized.