Design of optical systems with toroidal curved detectors

TL;DR

This paper explores the use of toroidal curved detectors in optical systems, showing that re-optimizing for such detectors can significantly enhance image quality, with practical methods for shaping the detectors demonstrated.

Contribution

It introduces the concept of using toroidal curved detectors in optical design and demonstrates their benefits through analytical and finite-element analysis.

Findings

Up to 40% improvement in image quality with toroidal detectors.

Toroidal shape can be achieved by bending a thin detector.

Applicable to re-imaging three-mirror anastigmats.

Abstract

We consider using toroidal curved detectors to improve the performance of imaging optical systems. We demonstrate that some optical systems have an anamorphic field curvature. We consider an unobscured re-imaging three-mirror anastigmat as an example (f'=960 mm, F/5.3, FoV 4x4 degrees). By assuming that the image is focused on a toroidal detector surface and perform re-optimization, it becomes possible to obtain a notable gain in the image quality - up to 40 % in terms of the spot RMS radius. Through analytic computations and finite-element analysis, we demonstrate that this toroidal shape can be obtained by bending of a thinned detector in a relatively simple setup.