Patent ID: 7289735

Claim:
A light emitting apparatus for emitting light with a controllable degree of polarization (DoP), comprising: a first optical emitter for emitting a first at least partially polarized light beam having a prevailing polarization component; a second optical emitter for emitting a second at least partially polarized light beam having a prevailing polarization component; a beam combining means for combining the first and second light beams into a combined beam of light wherein the prevailing polarization components of the first and second beams of light are mutually orthogonal; and, a DoP control means comprising: modulating means for modulating output powers of the first and second optical emitters with first and second distinct modulating signals, respectively; detecting means disposed to receive at least a portion of the combined beam of light for detecting a modulation component thereof related to the first and second distinct modulating signals; and, control circuitry coupled to the detecting means for maintaining a target DoP of the combined radiation by controlling an average output power of at least one of the first and second optical emitters in dependence upon the detected modulation component of the combined beam of light so as to maintain a ratio of the first and second distinct modulating signals in the combined beam of light at a pre-determined value corresponding to the target DOP.