Preliminary Evaluation of Radiation Total Ionization Dose Influence on the Optical Transmittance of CBERS 3&4 Multispectral Camera (MUX) Subsystem

Abstract. This paper is result of a preliminary work that has been carried out to evaluate the influence of space radiation total ionization dose on the optical transmittance of the CBERS 3&4 Multispectral Camera (MUX) Subsystem. The exposure of optical glasses used in the lens system to ionizing radiation generates color centers which decrease the total optical transmittance of the optics and, consequently, reduce the signal-to-noise ratio. The experimental transmittance of optical glass samples was determined for different dose values, yielding the dose coefficient curve and allowing the extrapolation of the transmission loss due to radiation at any dose level. The results were used to have a first estimative of the system total transmittance after the three years of mission