Alignment Reaseach Of A Catadioptric Asstronomy Telescope

With the use of aspherical mirror, the property of the system could be designed better, so there are more and more complicated systems with perfect imaging quality. But on the other hands, the difficulty of the alignment is bigger, so how to realize the high precision alignment is urgent.Based on a practical RC telescope system whose focus length is 560mm and diameter is 150mm, the alignment method is researched, which includes the micro-stress assemble and optical alignment machining of aspherical mirror, axis replacing and vertical optical alignment used to realize the high co-axiality, the computer-aided alignment based on interferometry collimating testing. The final system RMS is 0.05λ.This thesis mainly focuses on following aspects:1.The relationship between the system aberration and Zernike coefficients is introduced. With the analyses of the RC optical system, it is conclude that the system aberration of several sight of view is essential to ensure the good imaging quality of all sight of view.2.The influence of reflector’s surface error to the system aberration is researched. It is conclude that the micro-stress assemble of reflector is essential. Also how to realize the micro-stress of reflector in four kinds of supporting structure are analyzed.3.A method of axis replacing and vertical optical alignment is used to realize the high co-axiality. For the optical alignment machining, the shaking amount of spherical center image and the movement amount of the end surface are both adjusted and controlled. By using interferometry collimating testing of wave aberration, combined with the vector wavefront aberration theory, the amount and the direction of the misalignment can be calculated. The elements of optical system are adjusted according to the amount and the direction of the misalignment.