ROD INTEGRATOR THAT REDUCES SPECKLE IN A LASER-BASED PROJECTOR

摘要

The present invention provides an optical component (100 700 800 900), projection engine (200-300), and method that reduces laser speckle and at the same time ensures homogeneous illumination of a projected image. By combining a laser with a rod integrator (100 700 800 900), part of the laser light can be forced to pass through the rod integrator (100) several times before exiting and hitting a spatial light modulator, such as a transmissive LCD panel. When the length of the rod integrator (100 700 800 900) is in the order of the coherence length of the laser or larger, significant speckle reduction is obtained, while at the same time the illumination profile is homogenized.