Theoretical Simulation of X-ray Transmission Through a Polycapillary X-ray Lens with a Variable Capillary Radius

This article presents a model for simulating the X-ray transmission properties of a polycapillary X-ray lens in which the capillaries are arranged in a layered hexagonal structure. Each layer consists of hexagonally shaped capillary bundles which are arranged symmetrically around a centerline, and the capillary radius varies with the layer. The transmission efficiency of X-rays in different layers is studied, and by designing the capillary radius, a uniform X-ray intensity distribution is generated at the output of the polycapillary parallel X-ray lens, which has remarkable differences with the distribution of a conventional polycapillary parallel X-ray lens. In addition, several common defects in the manufacturing process of the polycapillary lens are simulated.