摘要 |
The illumination system has a plurality of light emitters (R, G, B) and a light collimator ( 1 ) for collimating light emitted by the light emitters. Light propagation in the light-collimator is based on total internal reflection (TIR) towards a light-exit window ( 4 ) of the light-collimator. At least one light sensor ( 8 ) for optical feedback is placed outside the light-collimator and is arranged to receive light emitted by the light emitters exclusively through reflection at the light-exit window of the light-collimator. Preferably, the light sensor is placed substantially coplanar with the light emitters. Preferably, a side wall ( 35 ) of the light-collimator is provided with a protruding portion ( 9 ) for guiding the light reflected at the light-exit window of the light-collimator towards the light sensor. Preferably, the illumination system is provided with a reflector ( 12 ). Preferably, the illumination system comprises a holographic diffuser ( 17 ). Accurate sensing of the color mixing of light emitted by the illumination system is obtained.
|