Research On Microlens Array-Based Optical Expanding And Coupling Beam Technology

With the development of science and technology, infrared target simulator has become an important component of the missile simulation system that consisting the interference source, compound lens, the beam expander and collimating lens of four parts. Microlens arrays as beam expanders could effectively solve the point target simulator's multi-beam expansion problem. This paper acquired the optical design of microlens array as a beam expander, analyzed the structural parameters, position errors and other factors on the influence of the system's coupling efficiency. The main contents include the following three aspects:(1) According to the point source target simulator's optical system, four existing beam expander devices, such as the netted mirror, optical fiber image bundles, light scattering component and microlens array are introduced, and their principles of expanding beams are analyzed. The feasibility of these four devices is discussed. Finally, microlens array is selected as the beam expander component in this device.(2) According to the system indicators, microlens array beam expander is designed. The structure parameters of silicon microlens array: the microlens aperture, the microlens radius and substrate thickness are identified. The error factors, such as the processing error, environmental temperature and position errors, are analyzed on the influence of the system's coupling efficiency.(3) As the limitations of the existing fabrication technology, there are some errors in processed sample. The processed sample is examined and simulated to determine whether it meets the requirements of beam expand and the coupling efficiency. The results show that the processing error within a certain range could meet the system requirement.The results of this paper show that the microlens array as point source target simulator's coupling beam expander optical components is feasible in fabrication techniques and principle. The results could be used for the further study of the devices, and could provide data support for the devices'fabrication and alignment.