MULTI-FUNCTION DIFFRACTIVE BEAM SAMPLERS FOR COMPACT DIAGNOSTIC MODULES

PHASE GRATINGS THAT CAN GENERATE ARBITRARY OUTPUT ARE USEFUL FOR BEAM DIAGNOSTICS, MULTICHANNEL IMAGING, OPTICAL COMMUNICATIONS, AND OPTICAL DIGITAL COMPUTING. BY USING DIRECT-WRITE METHODS FOR FABRICATING SURFACE-RELIEF DIFFRACTIVE OPTICS, UNIQUE BEAM SHAPING FUNCTIONS CAN BE IMPLEMENTED THAT WOULD BE EXTREMELY DIFFICULT OR IMPOSSIBLE BY HOLOGRAPHIC METHODS. USING AN ITERATIVE FOURIER-TRANSFORM ALGORITHM FOR PHASE-GRATING GENERATION, A SIGNIFICANT REDUCTION IN COMPUTATIONAL REQUIREMENTS CAN BE ACHIEVED. THE ABILITY TO WRITE GENERAL PATTERNS MEANS THAT ADDITIONAL PHASE FUNCTIONS SUCH AS OPTICAL POWER CAN BE IMPLEMENTED IN THE STRUCTURE OF THE BEAM SAMPLER. SEVERAL PHASE LEVELS, INCLUDING CONTINUOUS PHASE, CAN BE USED TO SYNTHESIZE THE OPTICAL TRANSFORMATION. IN THIS PROJECT, THE PHASE I RESEARCH INVESTIGATES THE FEASIBILITY OF GENERATING COMPACT, DIAGNOSTIC MODULES THAT USE DIFFRACTIVE OPTICAL PHASE PLATES FOR IMPLEMENTATION IN THE U-AVLIS PROGRAM. THE TWO-DIMENSIONAL DESIGNS ARE BEING ANALYZED UNDER CONDITIONS IMPOSED BY THE MISSION. DIRECT-WRITE, SURFACE-RELIEF DIFFRACTIVE ELEMENTS OFFER THE POTENTIAL FOR NEW ADVANCES IN MODULAR BEAM DIAGNOSTIC SYSTEMS. SEVERAL TASKS MAY BE PERFORMED SIMULTANEOUSLY TO PROVIDE A FEEDBACK PROCESS WHERE THE BEAM PARAMETERS ARE TIGHTLY CONTROLLED.