IGF::OT::IGF OUR PROPOSED INNOVATION IS A ROBUST MANUFACTURING PROCESS FOR FREE-FORM OPTICAL SURFACES WITH…

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IGF::OT::IGF OUR PROPOSED INNOVATION IS A ROBUST MANUFACTURING PROCESS FOR FREE-FORM OPTICAL SURFACES WITH LIMITED MID-SPATIAL FREQUENCY (MSF) IRREGULARITY ERROR. NASA AND MANY OTHERS HAVE A DIRECT AND CRITICAL NEED FOR HIGH QUALITY FREE-FORM OPTICAL COMPONENTS. FREE-FORMS CAN IMPROVE THE OPTICAL PERFORMANCE OF MANY TYPES OF OPTICAL SYSTEMS WHEN COMPARED TO ASPHERES. MSF ERROR IS A MAJOR CONCERN WITH FREEFORM OPTICS AS THE STANDARD METHOD FOR MANUFACTURING FREE-FORMS (SUB-APERTURE TOOL POLISHING) CAN LEAD DIRECTLY TO LARGE MSF ERROR. SIMPLY, MSF ERROR IS A HEIGHT ERROR ON THE SURFACE IN THE SPATIAL REGIME BETWEEN ROUGHNESS (MICRO) AND IRREGULARITY (MACRO). MSF ERRORS DRAMATICALLY DEGRADE PERFORMANCE IN OPTICAL SYSTEMS. OUR FREE-FORM MANUFACTURING PROCESS IS DIFFERENTIATED BY FULL-APERTURE POLISHING STEP, CALLED VIBE, AND BY THE PROPOSED SMOOTHING STEP. THE VIBE STEP DOES NOT CREATE MSF ERROR AS THE SUBAPERTURE PROCESS DOES. THE SMOOTHING STEP WILL REDUCE ANY INHERENT MSF ERROR. IN THIS MANNER, WE WILL MANUFACTURE FREE-FORM OPTICAL SURFACES WITHOUT MSF ERRORS. OUR TECHNICAL OBJECTIVES ARE THREE FOLD: 1) DETERMINE MOST FEASIBLE SMOOTHING PARAMETERS, 2) DETERMINE FEASIBILITY OF SMOOTHING FOR FREE-FORMS FOR REDUCED MID-SPATIAL FREQUENCY ERROR, AND 3)DETERMINE THE EFFECTIVENESS OF USING A COMPUTER GENERATED HOLOGRAM (CGH) FOR FREE-FORM MEASUREMENTS. TO ACCOMPLISH THESE OBJECTIVES WE HAVE SET OUT THE FOLLOWING WORK PLAN. FIRST WE WILL DESIGN THE FREE-FORM SURFACE AND THE ASSOCIATED CGH (WITH FEATURE FOR EASY ALIGNMENT). NEXT, WE WILL PERFORM A STUDY ON SMOOTHING TO DETERMINE THE OPTIMIZED SMOOTHING PARAMETERS TO REMOVE MID-SPATIAL FREQUENCY ERRORS ON FREE-FORM SURFACES. THEN, WE WILL MANUFACTURE PRECISION FREE-FORM SURFACES USING THE OPTIMIZED PARAMETERS. DURING EACH STEP IN THE MANUFACTURING PROCESS (GENERATION, VIBE POLISHING, SMOOTHING, SUB-APERTURE FIGURE CORRECTION, AND SOMETHING) WE EVALUATE BOTH THE IRREGULARITY AND MID-SPATIAL FREQUENCY ERRORS.