On-site optical wavefront testing and control for the AIMS solar telescope

Abstract

The Accurate Infrared Magnetic Measurement System (AIMS) solar telescope is the world’s frst mid-infrared observational system dedicated to high precision measurements of solar magnetic felds and independently developed in China. The large number of optical components, multiple intermediate focal planes, and the long optical path together with constraints on dome space and site thermal control signifcantly increase the complexity of system alignment and verifcation. Therefore, accurate surface fgure measurement of optical elements and precise wavefront control at each focal plane are critical to achieving the desired imaging performance. In this work, we investigated the wavefront control strategy of the telescope during assembly and alignment at a representative elevation angle. We present an on-site wavefront testing strategy that enables accurate surface verifcation and multi-focalplane wavefront control under severe spatial and thermal constraints. Furthermore, a comprehensive wavefront testing scheme for routine telescope operation after commissioning was introduced. The achieved system performance meets the design expectations, providing essential technical support for stable solar observations at the Lenghu site.