GENERATION OF LARGE-DIAMETER DIFFRACTIVE ELEMENTS WITH LASER PATTERN GENERATION

We describe the design and construction of a high-precision laser writ ing machine for the direct generation of large-diameter rotationally s ymmetric diffractive optics with continuous profiles in photoresist. T he photoresist profile can be used as a replication master surface or etched into a silica substrate. Machine design methodology, as well as qualification of performance, is provided. Test results for an f/2 10 0-mm clear-aperture diffractive lens directly etched into a silica sub strate are presented. Diffraction efficiency as a function of zone spa cing and wave-front performance are given. (C) 1997 Optical Society of America.