We report the optical design of an infrared (0.85-1.8 μm) pyramid wavefront sensor (IRPWFS) that is designed for the 6.5m MMT on telescope adaptive optics system using the latest developments in low-noise infrared avalanche photodiode arrays. The comparison between the pyramid and the double-roof prism based wavefront sensors and the evaluation of their micro pupils’ quality are presented. According to our analysis, the use of two double-roof prisms with achromatic materials produces the competitive performance when compared to the traditional pyramid prism, which is difficult to manufacture. The final micro pupils on the image plane have the residual errors of pupil position, chromatism, and distortion within 1/10 pixel over the 2×2 arcsecond field of view, which meet the original design goals.

Date Published: 5 September 2017
PDF: 11 pages
Proc. SPIE 10401, Astronomical Optics: Design, Manufacture, and Test of Space and Ground Systems, 104011H (5 September 2017); doi: 10.1117/12.2273290

Published in SPIE Proceedings Vol. 10401:
Astronomical Optics: Design, Manufacture, and Test of Space and Ground Systems
Tony B. Hull; Dae Wook Kim; Pascal Hallibert, Editor(s)