Abstract

Phase plates have been used in. holography¹ and laser fusion² to produce a well-defined far-field intensity envelope that is relatively independent of the input-beam profile. However, superimposed on this envelope is unwanted highly modulated speckle from the interference between different phase-plate elements. The speckle can have deleterious effects such as creating intensities in the nonlinear region of a hologram-recording medium or by initiating filamentation and hydrodynamic instabilities in laser-fusion applications. A technique has been developed for choosing the phase-plate elements (in combination with polarization rotation) such that these intensity fluctuations approach zero in the limit of plane-wave nearfield irradiation. Such phase plates are referred to as zero-correlation masks (ZCM).

© 1993 Optical Society of America