Abstract
In this study, we improved a Cassegrain concentrator [Appl. Opt.
59, 8603 [2020)APOPAI0003-693510.1364/AO.400756] by
redesigning the secondary optical element (SOE) with a freeform
design, including geometrically mapped and tilted steps, to replace
the design of the primary optical element (POE). This modification
increased the acceptance angle and formed a more uniform irradiance
distribution in the system without a homogenizer while maintaining the
same level of efficiency. The result is a 1236× geometric concentration ratio, 1035× concentration ratio, 83.73% optical
efficiency, ±0.40∘ acceptance angle, 8.96 uniformity,
and 0.254 aspect ratio.
Funder
National Science and Technology Council