Research On Multi-channel Optical System And Measurement Capacity For Atmospheric Background Measure

Aerosphere is the guarantee for the lives of earth beings. Following the extend of people's volitant space and concerned the safe of country, the people begin to dispose space detector to measure the aerosphere. The purpose of doing this is to accumulate experience about target identify plan and system design after the research of measurement for atmosphere background. The thesis focus on the research about multi-channel optical system and metrical ability for background measurement. Mainly including:Firstly, the performance and characteristics of optical systems used in background metrical system are analyzed. Then, the background characteristics of atmosphere and the influence of atmosphere transmission are introduced briefly.Secondly, the multi-channel optical system of American MSTI-3 used for background measurement are researched detailedly, mainly including: (1)the characteristical parameters of optical system are demonstrated; (2)the optical structure layout traits and main function of every channel are analyzed carefully; (3)every channel of optical system is simulated by using optical software ZEMAX and the imaging qualities are evaluated; (4)the thermal focus shift of MWIR channel and SWIR channel are calculated, the thermal compensatory measure which is used in MWIR and SWIR channel of MSTI-3 optical system is analyzed detailedly; (5)the signal noise ratio of every channel of MSTI-3 optical system is calculated so as to evaluate the performance of the whole system; (6)the opti-mechanical model of MSTI-3 multi-channel optical system is established by using thermal stray light analysis software Tracepro, then, the stray light radiation is analyzed. In this part, the main task is to analyze the restraining effect of field stop and baffling shutter which is shaped taper; the task also focus on the influence of mechanical structure's inner radiation by itself in wave band 4.21~4.43μm. By using Tracepro, the merits of using new shape cold stop and refrigerating the optical system part by part are validated.Lastly, according to the imaging quality, some improvements are made to the VNIR optical system channel. The imaging quality of improved VNIR optical system is better than the original one; according to the requirement of signal noise ratio, the thesis puts forward new indices of optical system, designs the new multi-channel optical system and distributes tolerances.