Diffractive shaping of the intensity distribution of a spatially partially coherent light beam

摘要

A new method is introduced to shape the intensity distribution and improve the quality of a beam emitted by a spatially partially coherent source with the aid of a periodic diffractive optical element (704). Periodic diffractive elements are not suitable for shaping spatially coherent light fields in the sense described in the invention because of the appearance of strong constructive interference effects, but the partial spatial coherence of light fields emitted by multimode sources suppresses these effects. The invention can be applied to shaping of intensity distributions emitted by lasers, light-emitting diodes, or optical fibers either, at a finite distance from the source (703) or in the far field. The invention is particularly advantageous in the shaping and quality improvement of beams emanating from high-power excimer lasers, semiconductor lasers, resonance-cavity light-emitting diodes, or arrays of lasers or light-emitting diodes (702, 705).