Impact of the LCD monitor locations on a novel alignment method: The combination of deflectometry and the sine condition test

Abstract

We have proposed a new alignment method which is the combination of deflectometry and the sine condition test. One of the great advantages of the new approach is that we need a camera and an LCD monitor larger than the clear aperture of the telescope instead of an interferometer and a return flat. To determine the state of the alignment, we have to place the monitor at two different locations: ideally at the rear principal plane of the telescope and a few meters displaced from the rear principal plane. However, for practical reasons, we may have to place the monitor closer to the telescope. We have simulated how changing the monitor location impacts the alignment, and we show the consequences of variations in the LCD locations on the alignment of a telescope using the new method. Copyright © 2022 SPIE.