An illumination device comprising: - a plurality of light sources emitting light along an optical axis; - a light collector adapted to collect light from the light sources and adapted to project at least a part of said light along said optical axis, wherein the plurality of light sources comprises, such as consists of: - a first group of light sources comprising a plurality of light sources, which can be driven to emit white light, such as the first group of light sources being white light sources, such as the first group of light sources being phosphor-converted white light emitting diodes (LEDs), - a second group of light sources comprising a plurality of light sources which can be driven, such as can only be driven, to emit non-white light, such as light having a positive D uv value, such as green light, such as the second group of light sources being green light sources, characterized in that the plurality of light sources can be driven so that - a total D uv value of light emitted from the illumination device is closer to zero, such as at least 0.001 or 0.002 or 0.0003 or 0.005 D uv points closer to zero, than each of a first D uv value of light emitted from the illumination device originating from the first group of light sources and a second D uv value of light emitted form the illumination device originating from the second group of light sources, and - a luminous efficacy of the second group of light sources is higher, such as at least 10 % higher, such as at least 15 % higher, such as at least 20 % higher, such as at least 30 % higher, such as at least 40 % higher, such as at least 50 % higher, than a luminous efficacy of the first group of light sources, such as when driven at identical conditions, such as identical current and (junction) temperature. - a plurality of light sources emitting light along an optical axis; - a light collector adapted to collect light from the light sources and adapted to project at least a part of said light along said optical axis, - a first group of light sources comprising a plurality of light sources, which can be driven to emit white light, such as the first group of light sources being white light sources, such as the first group of light sources being phosphor-converted white light emitting diodes (LEDs), - a second group of light sources comprising a plurality of light sources which can be driven, such as can only be driven, to emit non-white light, such as light having a positive D uv value, such as green light, such as the second group of light sources being green light sources, characterized in that the plurality of light sources can be driven so that - a total D uv value of light emitted from the illumination device is closer to zero, such as at least 0.001 or 0.002 or 0.0003 or 0.005 D uv points closer to zero, than each of a first D uv value of light emitted from the illumination device originating from the first group of light sources and a second D uv value of light emitted form the illumination device originating from the second group of light sources, and - a luminous efficacy of the second group of light sources is higher, such as at least 10 % higher, such as at least 15 % higher, such as at least 20 % higher, such as at least 30 % higher, such as at least 40 % higher, such as at least 50 % higher, than a luminous efficacy of the first group of light sources, such as when driven at identical conditions, such as identical current and (junction) temperature.