Patent ID: 7473879
Filing Date: 2009-01-06
Classification: F21K,F21V,F21Y,H05B

Abstract:
1. A light source comprising a first component light source, said component light source comprising: N LEDs, each LED having a light emitting chip in a package, said light emitting chip emitting light in a forward direction through a top surface of said light emitting chip and light in a side direction through a side surface of said light emitting chip, wherein N>1, said light generated in said forward direction being determined by a drive signal coupled to that LED, a portion of said light in said side direction leaving said package; a photo-detector; and a light redirector positioned to scatter a portion of said light in said side direction that leaves said package of each of said LEDs onto said photo-detector, said photo-detector generating N intensity signals, each intensity signal having an amplitude related to the intensity of said light emitted in said side direction by a corresponding one of said LEDs and being independent of the intensity of light emitted by any other LED in said light source.