Patent ID: 8172415

Claim:
A color-tunable illumination system, comprising: a first light source, a second light source and a layer of first luminescent material being arranged inside a light mixing chamber having a light exit window for emitting the light therefrom, the first light source and the second light source each comprising at least one light emitting diode and emitting light of a first predefined color into the light mixing chamber, the first luminescent material absorbing light of the first predefined color and converting the absorbed light into light of a second predefined color different from the first predefined color, the first luminescent material being arranged remote from the first light source and the second light source, the first light source being positioned with respect to the first luminescent material for illuminating the first luminescent material with a first relative flux of light being a part of the light emitted by the first light source into the light mixing chamber, the second light source being positioned with respect to the first luminescent material for illuminating the first luminescent material with a second relative flux of light being a part of the light emitted by the second light source into the light mixing chamber, the first relative flux being different from the second relative flux, and a controller for controlling an intensity of the light emitted by the first light source relative to the intensity of the light emitted by the second light source for altering a flux of light of the first predefined color which illuminates the first luminescent material, or for controlling a position of the first light source with respect to the luminescent material relative to the position of the second light source with respect to the luminescent material.