Gaussian to super-Gaussian laser beam intensity profile conversion using glass micro-optic fabricated with reflowed photoresist

Abstract

Summary form only given. Some optical systems require both high laser power and high beam quality. The wavefront distortion induced by illuminating an absorbing transmissive optical material with a Gaussian beam is not parabolic in shape, which causes the laser beam quality to degrade. The thermal lens induced by a high-order super-Gaussian or top-hat intensity profile laser beam, however, is parabolic and does not degrade laser beam quality. To avoid laser beam duality degradation when passing through transmissive optics, we create a pair of optics, which convert a Gaussian intensity profile into a super-Gaussian profile for transmission through the absorbing optics, and then convert the super-Gaussian profile back into a Gaussian for subsequent use. We performed ray-optics modeling to determine the spatial phase profile necessary to convert a Gaussian intensity profile into a super-Gaussian intensity profile.