By applying the wavefront coding technique to an optical system, the depth of focus can be greatly increased. Several complicated methods, such as Fisher Information based method, have already been taken to optimize f...By applying the wavefront coding technique to an optical system, the depth of focus can be greatly increased. Several complicated methods, such as Fisher Information based method, have already been taken to optimize for the best pupil phase mask in ideal condition. Here one simple point spread function (PSF) based method with only the standard deviation method used to evaluate the PSF stability over the depth of focus is taken to optimize for the best coefficients of pupil phase mask in practical optical systems. Results of imaging simulations for optical systems with and without pupil phase mask are presented, and the sharpness of image is calculated for comparison. The optimized results showed better and much more stable imaging quality over the original system without changing the position of the image plane.展开更多
According to the Collins’ formula and its inverse diffraction computation,this paper presents an algorithm for reconstructing the object wavefront of a numerical holograph.To improve the quality of wavefront reconstr...According to the Collins’ formula and its inverse diffraction computation,this paper presents an algorithm for reconstructing the object wavefront of a numerical holograph.To improve the quality of wavefront reconstruction,a technique of eliminating the zero-order diffraction light is introduced,which is achieved by subtraction of two intensities of the interference patterns.The computer simulation and image processing show that the method of eliminating the zero-order diffraction beam can be applied to the wavefront reconstruction of inverse diffraction computation.展开更多
文摘By applying the wavefront coding technique to an optical system, the depth of focus can be greatly increased. Several complicated methods, such as Fisher Information based method, have already been taken to optimize for the best pupil phase mask in ideal condition. Here one simple point spread function (PSF) based method with only the standard deviation method used to evaluate the PSF stability over the depth of focus is taken to optimize for the best coefficients of pupil phase mask in practical optical systems. Results of imaging simulations for optical systems with and without pupil phase mask are presented, and the sharpness of image is calculated for comparison. The optimized results showed better and much more stable imaging quality over the original system without changing the position of the image plane.
基金Supported bythe Natural Science Foundation of Yunnan Province(2004F0025 M)
文摘According to the Collins’ formula and its inverse diffraction computation,this paper presents an algorithm for reconstructing the object wavefront of a numerical holograph.To improve the quality of wavefront reconstruction,a technique of eliminating the zero-order diffraction light is introduced,which is achieved by subtraction of two intensities of the interference patterns.The computer simulation and image processing show that the method of eliminating the zero-order diffraction beam can be applied to the wavefront reconstruction of inverse diffraction computation.