부산대학교 도서관

A new efficient and accurate method which identifies phase distribution of coherent light from its modulated intensity images has been developed. This method is summarized as the following. 1) The observation equations of the conventional method is simplified. The unknown phase distribution is expanded to Zernike series and neglected its higher order terms. Then the identification problem reduced to the non linear optimization problem whose design valuables are the Zernike coefficients. These treatment regularized the ill condition of the problem. The non-linear optimization problem could be solved by the quasi Newton method. 2) Fast Fourier Transform was applied to the large scale matrix calculation, in order to decrease the computational time. 3) The matrix which represents the coherent light propagation is accurately modeled with boundary element method. 4) Some numerical example problems are solved to demonstrate the effectiveness of the present method. 5) Practical experiment was performed, and the phase distribution could be identified from real data within two seconds. It is noted that various types of optical setting can be employed to modulate the light.