The energy utilization rate of excimer lasers has become an important factor restricting its further development in the processing field. In order to solve this problem, this paper carried out research and design of a new type of tapered optical element for excimer laser convergence. Through the extraction and simulation of the outer contour of the taper quartz tube, combined with the variation of the melting zone during the taper process, the curve function of the taper region is obtained, which is corrected and compared with the outer contour data of a large number of taper quartz glass tubes. Get the taper shape function. Based on the shape function to simulate the actual shape of the component, the actual loss and spot shape of the beam are simulated by the tracking of the beam and the calculation of the loss. Finally, a taper optical element is fabricated based on the function curve of the simulation result. After the excimer laser passes through the optical system, a circular spot with an inner ring diameter of 100 μm can be obtained at the light exiting port, and the utilization rate of light energy is about 80%, which solves the problem that the excimer laser spot shape is irregular and the energy distribution is uneven.