LED luminaire with electrically adjusted color balance using photodetector

摘要: The combined light output (chromaticity) of a white emitting LED luminaire is electronically controlled based on measurements by single photodiode arranged to measure the outputs at least plurality LEDs in array. This accomplished measuring each color separately sequence time pulses. For an array red, green, and blue there are three pulses sequence. During pulse, current for being measured turned off. response typical extremely short, so can be performed sufficiently short that an-observer will not detect it (e.g. 10 ms). Measured colors compared desired outputs, which may set user controls, changes power supply blocks made as necessary. Chromaticity thus automatically without regard factors cause change. inputs permit varying chromaticity either warm (more red output) or cool output).