A generalized expression for accelerating beamlet decomposition simulations.

Paraxial diffraction modeling based on the Fourier transform has seen widespread implementation for simulating the response of a diffraction-limited optical system. For systems where the paraxial assumption is not sufficient, a class of algorithms has been developed that employs hybrid propagation physics to compute the propagation of an elementary beamlet along geometric ray paths. These "beamlet decomposition" algorithms include the well-known Gaussian beamlet decomposition (GBD) algorithm, of which several variants have been created. To increase the computational efficiency of the GBD algorithm, we derive an alternative expression of the technique that utilizes the analytical propagation of beamlets to tilted planes. We then use this accelerated algorithm to conduct a parameter-space search to find the optimal combination of free parameters in GBD to construct the analytical Airy function. The experiment is conducted on a consumer-grade CPU, and a high-performance GPU, where the new algorithm is 34 times faster than the previously published algorithm on CPUs, and 67,513 times faster on GPUs.

Modeling and characterization of OASIS inflatable primary antenna by dual modality metrology.

OASIS (Orbiting Astronomical Satellite for Investigating Stellar Systems) is a space-based observatory with a 14 m diameter inflatable primary antenna that will perform high spectral resolution observations at terahertz frequencies. The large inflatable aperture, non-traditional surface configuration, and the double layered membrane structure afford unique challenges to the modeling and testing of the primary antenna. A 1-meter prototype of the primary antenna (A1) was built to validate our technical approach. A laser radar coordinate measuring system was adopted to measure the shape of A1. In addition, deflectometry was performed to monitor the stability of A1 during the radar measurement. Test cases pertaining to specific operational conditions expected for the 14 m OASIS primary were explored. The measured data were then compared to the Fichter model and Finite-element Analyzer for Inflatable Membranes (FAIM).