Zoom optics in fourth-generation synchrotron radiation: Design and simulation

Brilliance of the fourth-generation synchrotron radiation sources are increased in the order of magnitude, which further emphasizes the coherent applications. The zoom system of traditional optics can realize coherence regulation while achieving the target size of focus spots at designated position. This paper develops the design method of zoom system to fully exploit partially coherent fields. According to the first-order optics and imaging theory, the design method is reasonably simplified. The flux-optimization acceptance-angle ratio approximately linearly varies with the coherent fraction, which contributes to the slit-aperture determination. In order to validate the design method, wave-optics simulations are conducted in this paper.