Simulation and characterization of ellipsoidal monocapillary X-ray lens with a micro focal spot for high energy X-ray

To obtain high-energy X-ray micro-focal size for monocapillary X-ray lens in X-ray micro-area analysis, a high-energy X-ray micro-focal spot lens based on ellipsoidal monocapillary was designed and simulated．The inner surface of lens coated with metal oxide film was simulated, the composition of which was HfO₂．Simulations showed that both coated and ordinary glass lens could focus X-rays at 100 keV into a focal size below 10 microns．Compared with ordinary glass lenses, the upper limit of X-ray focusing energy was increased 2-fold after coating the lens．To improve input flux, the coated lens was redesigned．Compared with glass lens, newly coated lens showed a 3.8-fold increase in luminous flux at the focal size at 100 keV, the power density gain increased by an order of magnitude, indicating that lens coating was valuable to focus high-energy X-rays．It is concluded that simulations could guide fabrication and application of ellipsoidal monocapillary high-energy X-ray lenses．