Study On The Spectral And Radiometric Calibration Of Solar Spectrometer In The Visible Spectral Range

Promoted by atmospheric physics,solar physics,climatology,meteorology and environmental science,the measurement of extraterrestrial solar spectral radiation is a growing research field based on advance of space exploration technology.For high accuracy solar spectral irradiance measurement,Changchun Institute of Optics,Fine Mechanics and Physics(CIOMP)is developing a new generation broad band(165nm-2400nm)spaceborne solar spectrometer.The thesis studied the spectral and radiometric calibration of extraterrestrial solar spectrometer in the visible spectral range developed by CIOMP.The spectral and radiometric calibration devices were developed based on calibration theory,and the spectral and radiometric calibration of solar spectrometer in the visible spectral range was executed.The spectral irradiance responsivity of VIS solar spectrometer in the 400nm-700 nm range was obtained using NIST F661 FEL standard lamp and transferred F1391 FEL standard lamp.The output at extraterrestrial solar irradiance of VIS solar spectrometer in the 400nm-700 nm range was obtained too.The high voltage value of photomultiplier was selected as 510 V based on these data.The combined uncertainty of spectral irradiance responsivity of VIS solar spectrometer is 0.88%.Mercury lamp was used for wavelength calibration,and the linear relation between step number of stepping motor and corresponding grating wavelength is y=79.39x-8450.The linear relation was inputted into the control software of stepping motor.The precision of wavelength is 0.46 nm.The spectral resolution is 0.95 nm.The filter-double aperture linearity tester was built for linearity testing,and the conclusion is the linearity of VIS solar spectrometer photoelectricity detecting system is better than 2.5% at gain 1,0.5% at gain 2,and 0.1% at gain 3.The combined uncertainty of the linearity of VIS solar spectrometer photoelectricity detecting system is 0.88%.Shutter aperture was used to measure time constant of VIS solar spectrometer photoelectricity detecting system,the result is 1.2 second.F1391 FEL standard lamp and Gershun tube radiometer were used to test spectral irradiance stability of VIS solar spectrometer,the stability is 0.16%/hour.