US Patent 7642707 Electroluminescent device with a light conversion element

The invention relates to a light source to emit a mixture of primary and secondary light comprising an electroluminescent device like a light emitting diode LED or a laser, to emit the primary light into a light conversion element (3) to convert the primary light into the secondary light, where a first part of the primary light is emitted along a light path with a first conversion factor (11) for the primary light, and a second part of the primary light is emitted along a light path with a second conversion factor (12) for the primary light larger than the first conversion factor.