Patent ID: 7576478

Claim:
A color conversion cell for adjusting a color or color temperature of light from a light source having a first emission spectrum, the color conversion cell comprising a color converting substance in a matrix held between two electrodes, the color converting substance having a second emission spectrum different from the first emission spectrum, and a switchable reflector positioned behind the color converting substance such that the color converting substance is between the reflector and the light source, forming a switchable resonance structure for the first emission spectrum; the color conversion cell being shiftable between at least a first state wherein the reflector will at least substantially reflect source light incident on the cell, and the color converting substance will absorb a first ratio, A 1 , of light incident on the cell, emit light with the second emission spectrum, and transmit a second ratio, T 1 , of light incident on the cell, and a second state wherein the reflector will at least substantially transmit source light incident on the cell, and the first ratio, A 2 , is smaller than in the first state and wherein the second ratio, T 2 , is larger than in the first state.