MicroVision, Inc.
Method and apparatus for laser beam combining and speckle reduction

Abstract:

A beam combining device combines laser beams and performs speckle reduction of the laser light. Two laser beams are incident on a non-polarizing beam splitter and combined beams are split into two light paths with different optical path lengths. The two light paths may have different geometric path lengths and/or different indices of refraction in the paths to produce the different optical path lengths. One of the light paths is passed through a polarization rotation device and then the two light paths are recombined with a polarizing beam splitter to produce a combined reduced speckle laser beam.