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Behrang H. Hamadani, Jonathan E. Seppala, Clarence J. Zarobila
Abstract
Additive manufacturing methods based on photopolymerization offer a great potential for fabrication of high quality, highly transparent optical components. One appropriate use of these technologies is related to fabrication of parts that can be used in very specific and narrow applications, such as concentrating the output of a particular LED array down to a small but uniform spot for a required application. In this work, we first performed optical raytracing simulations to model an optimized freeform nonimaging concentrator for a custom 12- LED array and then fabricated different waveguide concentrators using 3D printing and characterized their optical characteristics. Our results demonstrate that realizing an intensity of 17 kW/m2 or more with a spatial irradiance nonuniformity of better than 2% over an area approaching 1 cm2 is realistic and that such an approach can rival intensities achieved with powerful lasers over a similar area
Hamadani, B.
, Seppala, J.
and Zarobila, C.
(2020),
3D printed optical concentrators for LED arrays, Optics Express, [online], https://doi.org/10.1364/OSAC.398260
(Accessed October 9, 2025)