A Novel Approach to Reduce Optical Aberrations by using Deformable Bushes at Opto-Mechanical Interfaces

Abstract

There is a continuous need to enhance the aperture size of telescopes by astronomers to explore the space much deeper by getting better resolutions and high image quality. Supporting large optics and maintaining high dynamic stability involves more number of constraints. This renders optical surface more distorted and results in poor image quality, since the image quality deteriorates with increase in RMS surface error. A new approach is proposed to introduce deformable bushes at the interfaces. These are tuned to deform under speci¯c clamping force and thus arrests all Degrees of Freedom (DOF). This limits the clamping force exerted by an axial DOF (Uz) to an insigni¯cant value. This approach helps to arrest Uz without imposing clamping stress on the opto-mechanical mount and brings down optical aberrations and enhances dynamic stability of the mounting system. This due to the fact that all clamping forces are taken by deformable bushes and the stress is not transferred to mount and thus does not contribute to non-uniformity of the optical surface. The non-uniformity of the optical surfaces in°uenced by clamping forces is simulated by Finite Element (FE) techniques. The use of deformable bush approach in minimizing optical aberrations and stability enhanced by additional constraints to opto-mechanical mounts are demonstrated by simulations.