Study Of Reflective Telescopes Alignment Based On Vector Wavefront Aberretion

Vector wavefront aberration theory, also known as nodal aberration theory (NAT), can quantitatively describe the wavefront aberration of optical systems under the influence of decenter and tilt of surface. By Vector wave aberration theory, wavefront aberration of misaligned optical systems can be analyzed to guide alignment of optical systems, and for some optical systems equations between the designed optical parameters, misalignment values and the wavefront aberration of misaligned optical system are established, misalignment values can be sovled through testing the wavefront aberration of misaligned optical system.Currently the alignment of high-precision reflective telescopes often use computer-aided alignment technology. Computer-aided alignment technology often used the mathematical methods of iteration or approximation to solve the amounts of misalignment, because of the lack of theoretical guidance, many practical problems were encountered. This dissertation researches on reflective telescope alignment based on vector wavefront aberration theory, the object of study is common two-mirror and three-mirror optical systems, the purpose of study is to improve the alignment efficiency of reflective telescopes and reduce the blindness of alignment which make up the defect of the computer-aided alignment technology. The main research contents are summarized in the following aspects:1. The first-order properties of decentered and tilted optical systems are analyzed in detail, the relation formula between aberration field center and decenter and tilt of each optical component is derived.2. The behavior of third-order aberration in decentered and tilted optical systems are described in detail, focusing on distribution of the coma, astigmatism and field curvature in the entire field of view.3. Using vector wavefront aberration theory, theoretical issues to align two mirror telescopes is discussed, the necessary conditions of aligned two-mirror telescopes is summarized, a method based on vector wavefront aberration theory and interference wavefront aberration testing technique is introduced which can exactly solve the misalignment values.4.The behavior of wavefront aberration of misaligned three-mirror telescopes in the whole field of view is analyzed, theoretical issues to align three mirror telescopes is discussed, and some important conclusions is obtained.