Analysis,Measurement And Correction Of Stray Light In Imaging Spectrometer

Imaging spectrometer can obtain one dimensional spectral information and twodimensional spatial information(data cube)at the same time.It is widely used in remote sensing fields such as military reconnaissance,geological exploration and marine pollution monitoring.Stray light is an important parameter for imaging spectrometer.It will affect the detection of dim target information.Therefore,the analysis,measurement and correction of stray light in imaging spectrometer is of great significance.In this paper,the stray light simulation analysis,experimental measurement device and stray light correction method of imaging spectrometer at home and abroad are summarized.Based on the basic theory of stray radiation and the imaging spectrometer studied,the sources of stray light are analyzed,and the relevant suppression measures of stray light are introduced.Then,based on the asymmetry of the field of view of the Offner imaging spectrometer studied,a baffle is designed and the extinction ratio of two different angles of incidence in the field of view is given.According to the optical design requirements,the system's optical machine modeling is carried out,and the scattering path of the system is given.Finally,the spectral dimension veiling glare of the imaging spectrometer is simulated based on the notch method.The veiling glare at the notch wavelength of 633 nm is 0.34%,which satisfies the requirement of the miscellaneous light coefficient less than 1%.Then,the existing method of measuring stray light of imaging spectrometer is compared.According to the characteristics of the Offner imaging spectrometer studied in this paper,a set of measurement of the stray light based on the notch method is designed.The actual measurement of the veiling glare is 0.84%.The uncertainty of the measuring results is evaluated by the GUM method,the error source of the stray light measurement device is analyzed.The optimal estimation value and the expansion uncertainty of the stray light are given.Finally,the principle of stray light correction matrix is introduced,and the dynamic range of the measuring device is expanded by using the attenuation plate.The relevant data are measured and the stray light correction matrix is processed,and the stray light of the imaging spectrometer is effectively corrected by the stray light matrix.The research work provides a technical guarantee for the study of stray light in imaging spectrometer and the development of high resolution imaging spectrometer.