Patent ID: 7658528

Claim:
An illumination system comprising: a plurality of light emitters, a first light-collimator for collimating light emitted by the light emitters, the first light-collimator being arranged around a longitudinal axis of the illumination system, light propagation in the first light-collimator being based on total internal reflection, at least a second light-collimator for collimating light emitted by the light emitters, the second light-collimator being arranged around the first light-collimator along the longitudinal axis, light propagation in the second light-collimator being based on total internal reflection or on reflection at an outer surface of the second light-collimator facing away from the longitudinal axis, the first and the second light-collimator defining a cavity therebetween, a switchable optical element based on electrowetting disposed in the cavity, the switchable optical element being switchable in a mode of operation reducing the effect of the second light-collimator.