Automated design of a uniform distribution using faceted reflectors

Abstract

William J. CassarlyStuart R. DavidDavid G. JenkinsAndrew P. RiserOptical Research Associates3280 E. Foothill Blvd.Pasadena, California 91107E-mail: billc@opticalres.comThomas L. DavenportUniversity of ArizonaOptical Sciences Center1630 East University Blvd.Tucson, Arizona 85721Abstract. Faceted reflectors are a ubiquitous means for providing uni-form illumination in many commercial lighting products, examples beingnewer flashlights, department-store display lighting, and the faceted re-flectors found in overhead projectors. However, the design of facetedreflectors using software has often been more limited by the tools avail-able to design them than by the imagination of the designers. One of thekeys to enabling a broader range of design options has been to allowmore complex surfaces using constructive solid geometry (CSG). CSGuses Boolean operations on basic geometric primitives to define shapesto create individual facets. In this paper, we describe an improved fac-eted reflector design algorithm and use it to create a wide range of CSG-based reflectors. The performance of various reflectors is compared us-ing a Monte Carlo ray-trace method.