Wide-field optical design for a 60 m submillimeter telescope

作者：Zheng Lou, Yingxi Zuo, Qijun Yao, Sheng‐Cai Shi, Ji Yang, Xuepeng Chen · 发表于：Applied Optics · 年份：2020 · DOI：10.1364/ao.388320 · 被引用次数：9 · 研究领域：Adaptive optics and wavefront sensing、Optical Coatings and Gratings、Advanced optical system design

We present a practical wide-field optical design for a 60 m aperture submillimeter telescope, which is currently under conceptual design study in China. The telescope is specified to operate over a wavelength range of 0.65–3 mm and provide a wide field of view (FOV) of 1° in diameter. We designed an F/6 Ritchey Chrétien (RC) system with a quasi-planar tertiary corrector, which cancels all spherical, coma, and astigmatism aberrations. It also achieves a good balance among the mirror sizes, central obscuration, and focal-plane curvature. The problems of focal surface curvature and nontelecentricity are treated in the subfield instrumental design, which employs a simple silicon wedge prism to obtain flat and telecentric focal planes for each subfield instrument module. Our studies show that by such a design, more than 10 5 detector pixels can be efficiently and uniformly fed at the shortest wavelength band with Strehl ratios above 0.85 across the entire 1° FOV. Several practical issues related to the telescope optics are also discussed.