A parallel, grey-scale direct-writer for micro-optics and microstructures

A novel method for fabricating diffractive microstructures is reported. By using a parallel direct-write technique based on a liquid crystal display, arbitrary structures with micrometer dimensions may be fabricated. Both binary and grey-scale structures can be made by direct two-dimensional modulation of the exposure with the LC display. A broadband UV lamp allows illumination of a variety of photoresists, including SU-8 or hybrid xerogels. With this method, creation of custom-made diffractive optics such as kinoforms, gratings or micro-lenses is inexpensive, fast and easy. Compared to existing manufacturing techniques, this direct-writing method simplifies component development by reducing the design-to-fabrication time and by not requiring cleanroom facilities.