Monte Carlo tolerancing tool using nonsequential ray tracing on a computer cluster

The development of a flexible tolerancing tool for illumination systems based on Matlab® and Zemax® is described in this paper. Two computationally intensive techniques are combined, Monte Carlo tolerancing and non-sequential ray tracing. Implementation of the tool on a computer cluster allows for relatively rapid tolerancing. This paper explores the tool structure, describing the splitting the task of tolerancing between Zemax and Matlab. An equation is derived that determines the number of simulated ray traces needed to accurately resolve illumination uniformity. Two examples of tolerancing illuminators are given. The first one is a projection system consisting of a pico-DLP, a light pipe, a TIR prism and the critical illumination relay optics. The second is a wide band, high performance Köhler illuminator, which includes a modified molded LED as the light source. As high performance illumination systems evolve, the practice of applying standard workshop tolerances to these systems may need to be re-examined.