Structural design of an improved SPIDER optical system based on a multimode interference coupler.

ABSTRACT

The Segmented Planar Imaging Detector for Electro-Optical Reconnaissance (SPIDER) is a small volume, lightweight, low energy consumption, and high-resolution system expected to replace traditional large aperture telescopes for long-distance detection. In this paper, an improved SPIDER system is proposed, which uses a multimode interference (MMI) coupler instead of an orthogonal detector, and successfully doubles the space spectrum coverage. We present a three-point configuring method to configure lenslets, calculate spatial spectrum values from the output currents obtained by MMI. By comparing the performance of the MMI-SPIDER and SPIDER systems through simulations, we demonstrate that the former has more complete spatial spectrum coverage, resulting in better image restoration quality.