Modeling UV-C irradiation chambers for mask decontamination using Zemax OpticStudio

Ultraviolet decontamination of personal protective equipment, particularly masks, is important in situations where mask reuse is practiced. To assist in the development of UV-C decontamination chambers, we have constructed ray tracing models in Zemax OpticStudio v20.1 for two distinct geometries, namely, a rectangular cabinet and a cylindrical can. These models provide irradiance distributions that can be used for comparison with experiment, as well as to predict local irradiance variation over the surface of a mask. In this paper we describe the model details, including: (1) a mask object in CAD format; (2) our assumptions for modeling surface properties; (3) the use of polygon object detectors for local irradiance analysis; and (4) experimental results that compare favorably to the simulations.