Optics and Photonics Society of Iran

In this article, by design of an optical null corrector, flat output wavefront of an interferometer is converted to parabolic wavefront and parabolic surfaces can be tested. In method that is presented in [1] it is necessary to do accurate adjustment of tilt and decenter of optical null corrector with respect to focal point of interferometer. Also, in [1] it is necessary to do accurate adjustment of distance between null corrector and focal point of interferometer. In new method that is proposed in this article, it isn't necessary to do accurate adjustment of decenter of null corrector with respect to output flat wavefront of interferometer and also it isn't necessary to do accurate adjustment on distance between null corrector and output flat wavefront of interferometer. By this two advantages, setup of test and its accuracy is improved dramatically.