Illumination design for high-contrast, high-power UV DLP projector

Abstract

The use of Digital Light Processing (DLP)-based technologies has driven innovation in industries such as additive manufacturing, metrology, lithography and, increasingly, biomedical research and bioprinting. In addition to image quality parameters (magnification, line contrast, distortion), two key characteristics govern the manufacturing success: intensity on the image plane, and Full On / Full Off (fo:fo) contrast. Both need to be balanced carefully in the illumination design. We discuss detailed considerations for developing an UV DLP projector. Specifically, by choosing TIR prism design rationale, fine tuning the exact geometry, tailoring the other illumination optics and an improved coating design, we achieve an illumination that is both high-contrast and high-intensity.