Optical integrating cavity lighting system using multiple LED light sources with a control circuit

摘要

A system to provide radiant energy of selectable spectral characteristic (e.g. a selectable color combination) uses an integrating cavity to combine energy of different wavelengths from different sources. The cavity has a diffusely reflective interior surface and an aperture for allowing emission of combined radiant energy. Sources of radiant energy of different wavelengths, typically different-color LEDs, supply radiant energy into the interior of the integrating cavity. In the examples, the points of entry of the energy into the cavity typically are located so that they are not directly visible through the aperture. The cavity effectively integrates the energy of different wavelengths, so that the combined radiant energy emitted through the aperture includes the radiant energy of the various wavelengths. The apparatus also includes a control circuit coupled to the sources for establishing output intensity of radiant energy of each of the sources. Control of the intensity of emission of the sources sets the amount of each wavelength of energy in the combined output and thus determines a spectral characteristic of the radiant energy output through the aperture.

主权项

1. A lighting system comprising:
a lighting fixture for a visible illuminating type lighting application in a region or area intended to be occupied by a person, the lighting fixture comprising: an optical integrating cavity having at least one white diffusely reflective interior surface and an optical passage for allowing emission of optically integrated light out of the cavity; and a plurality of light emitting diode (LED) sources 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 illuminating type lighting application; a control circuit coupled to the sources for establishing output intensity of light of each of the sources; and a deflector having a reflective inner surface coupled to the optical passage and configured to expand outward as it extends away from the optical passage for deflecting at least some of the optically integrated light emitted through the optical passage and defining a field of illumination for the emitted light with respect to the lighting application.