A calibration technique based on internally illuminated integrating sphere was presented

and the large area uniform (~2%) source of radiance close to ideal source was achieved

the radiance responsivities of the ultraviolet remote sensing spectroradiometer in space under development were obtained. Under the condition that FEL standard lamp was assumed to be a uniform point source

the illuminating factors of both sources were corrected

in the mean time

two kinds of diffusers were involved in the experimental research for this correction. A conclusion is given that the radiance responsivities of the spectroradiometer obtained through these two kinds of diffusers are consistent within 1%. A preliminary analysis of calibration data shows that the uncertainty of the spectral irradiance measurement in the quartz tungsten halogen lamp and the uncertainty in distance measurement are the major factors of uncertainty in the sphere calibration technique. This technique can be used to improve the precision of calibration in ultraviolet wavelength range

and the uncertainty in calibration can be reduced significantly too.