Method and device for characterizing a coherent light field in amplitude and phase

摘要

A method and a device for characterizing a coherent light field (1) in amplitude and phase are described with the following steps: Providing an object (10) with known transmission function T (x, y) for the light field (1) in amplitude and Phase; • irradiating the object (10) with the coherent light field (1) to be characterized in an object plane (11) in which the object (10) is arranged; • recording an intensity distribution I '(x, y) of the diffraction image (22 ) of the light field (1) spatially behind the irradiated object (10) in a detector plane (21) by means of an area detector (20); • Reconstructing the light wave function u (x, y) after it has passed through the object (10) by iteratively determining Phase and amplitude of the light wave from the recorded intensity distribution I '(x, y); • Calculation of the light wave (1) before it passes through the object by applying the known transmission function T (x, y) to the reconstructed light wave function u (x, y); It is provided that an object with a structure area (12) is used as the object (10), the structure area (12) of the object (10) being defined by a transmission mask which only contains strongly absorbing areas (13) with a transmission T ≈ 0 and non-absorbing areas (14) with a transmission of T ≈ 1.