Patent ID: 7479622

Claim:
A system comprising: A) a light fixture for a visible illuminating type lighting application, to illuminate or to provide task or object illumination, in a region or area intended to be occupied by a person, the light fixture comprising: 1) an optical integrating cavity having at least one diffusely reflective interior surface and an optical passage through a wall of the cavity for allowing emission of optically integrated light from the cavity; and 2) a plurality of sources of light coupled to directly supply light to the optical integrating cavity in one or more directions to cause substantial portions of light supplied by the sources to reflect from said at least one diffusely reflective surface of the optical integrating cavity one or more times to optically integrate the light from the sources before emission as the optically integrated light through the optical passage of the integrating cavity for the visible lighting application, at least two of the sources emitting light of respective different colors, wherein the sources provide sufficient light energy in the optically integrated light and the optical integrating cavity is configured to direct the optically integrated light emitted through the optical passage in a direction to facilitate said visible illuminating type lighting application; and B) a control circuit coupled to the sources for establishing output intensity of light of each of the sources to set contributions of the different colors to the optically integrated light within the cavity and thus set a spectral characteristic of the optically integrated light emitted through the optical passage of the optical integrating cavity.