Research On The Contrast Of Optical Diffraction Imaging

Modern diffraction optics technique based on optical diffractive imaging theory is a leading discipline crossing over optics and microelectronics. The diffraction optical elements are compact, light and easy duplicating which are applied in fiber communication, microelectronics mechanical system and national defense.The thesis did research on scalar diffraction theory based on optical diffraction imaging in visible range, and analyzed the contrast of diffraction element imaging quality. We did investigation on imaging distance and contrast when incident light passed through diffraction elements.The research is as following:(1)according to scalar diffraction theory, the basic theory and CAD method were described with diffraction element algorithm are compared and analyzed;(2)under Fresnel approximation of scalar diffraction, the contrast of single-point and multiple-point diffraction imaging quality phase distribution were analyzed with G-S iterative algorithm is analyzed by computing the digital holography through G-S algorithm in computer program;(3) the research on the influence of variation of beam radius to the quality of diffraction image when a Gaussian beam incident to a DOE based on a plane wave incident is carried out. The diffraction imaging process of a DOE based on a Gaussian beam irradiating is simulated;(4) the influence of incident angle of incident light to the quality of diffraction image was computed and analyzed.