Imaging analysis of holographic concave grating spectrometer

Abstract

The geometric aberration theory has widespread application in optical design because it can provide the concrete expressions of the various aberrations. Nevertheless, it is very complicatedto analyze the imaging quality of the concave grating by using the aberration theory, because it can’t provide intuitive imaging formula and quantitative spatial resolution. In contrast, holographic reconstruction theory can simplify imaging analysis and give concise results. In this work, imaging formula and magnification formula are achieved by using holographic reconstruction theory. Both the defocus distance from the real image plane to ideal image plane and the confusion diameter that are derived by using magnification formula and geometrical relationship.The results can provide useful information for intuitively understanding, analyzing the imaging properties of HCG and putting forward a good design idea. In addition, an HCG spectrometer is designed by geometric aberration theory and analyzed by the formula derived from holographic reconstruction theory. As a result, theoretical estimation is accordance with the software simulation.