Simulation of grazing-incidence coherent imaging

A method is proposed for simulating optical object images formed by oblique or grazing-incidence coherent beams. The theoretical approach relies on the solution of a parabolic equation, which generalises the Fresnel integral. Our numerical results are given for experimental conditions close to those realised when use is made of modern soft X-ray lasers. The newly developed method may also be employed to simulate X-ray imaging systems developed around synchrotron and free-electron laser beams.