The Baffle Of The Stray Light Suppression Performance Simulation Analysis And Optimization Design

Background stray light has a serious impact when the star sensor is in orbit. To a lesser extent, the signal-to-noise ratio is reduced, affecting the detection or identification ability of the system. In severe cases, the target signal is completely submerged and the system is not able to extract the target. As an important part of the space optical system, baffle has been widely used in suppressing the stray light effectively. However, the stray light suppression effect of the baffle is largely dependent on the selection of stray light material and the design of stray light suppression structure. In order to design and develop the baffle products with better stray light suppression performance, the performance simulation and optimization design of the baffle are studied, aiming at the stray light suppression requirements for practical engineering applications. The specific work includes the following aspects:(1) Theoretical analysis of stray light suppression. Based on the theory of radiation transfer, stray light suppression mechanism is elaborated by analyzing the reflection, scattering, diffraction and environmental stray light.And stray light suppression method is put forward from the baffle structural design, the design of aura block and the selection of material on the inner wall with high absorption rate. At the same time, scattering characteristics measurement and data processing is carried out for stray light suppression material. According to the read requirements of LightTools, format the measured data. Finally, from the structural design of baffle and aura block, the stray light suppression structure design is finished.(2) The simulation and verification of stray light suppression performance of the baffle.Reasonable evaluation index of the stray light suppression performance is built such as extinction ratio, the average energy density and energy concentration, focusing on the need for quantitative assessment of the stray light suppression performance. According to the structural design method of baffle model, build the baffle model in Solidworks and import the model into LightTools. At the same time, the setting of stray light suppression materials is completed, through the read on scattering characteristics files of inner surface of the baffle by LightTools. And obtain the evaluation results of stray light suppression performance by simulation analysis. In addition, based on baffle product which is designed and developed, verification experiment of the ground measurement is carried out to verify that the stray light suppression performance simulation method is correct.(3) The optimization design of the stray light suppression of the baffle. Based on the constructed structure model of the baffle, set different simulation input parameters and a lot of evaluation results of stray light suppression performance of the baffle are generated by the simulation of LightTools. According to the corresponding relation of simulation input parameters and results of performance evaluation, construct large sample space of the evaluation of the stray light suppression performance. Aiming at the constructed sample space, establish forecasting model of stray light suppression performance by using the Bayesian neural network algorithm. Finally,according to the actual needs of engineering design, the optimal structure model can be solved by using the forecasting model. The optimized design of stray light suppression can be realized.In a word, A series of research work includes the analysis of mechanism of stray light suppression, the acquisition and processing of the scattering data of stray light suppression materials, the design of stray light suppression components, the simulation and verification of stray light suppression and the optimization of stray light suppression performance. For the demand of practical engineering application, the research work constructs a set of scientific structure design and performance analysis method of stray light suppression and provides important technical support for the design and optimization of the star sensor and the performance evaluation of stray light suppression.