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As we know, optical solar reflector (OSR) is used as the thermal control element for communications satellites and other
spacecraft. The solar absorption, infrared emissivity and their ratio of OSR, are considered as the main standard of its
thermal control performance. OSR is divided into conducting OSR and non-conducting OSR. When using the indium
tin oxide (ITO) film coated on the surface of conducting OSR's glass substrate, ITO film will improve OSR's solar
absorption rate and reduce the infrared emissivity. That means the thermal control performance will be declined. The
paper is aimed to revealing the reverse association mechanism between the thermal control performance of conducting
OSR used for spacecraft and the antistatic properties of ITO film. First, we combined the Drude theory with the Thermal
radiation theorem to analyze how the antistatic parameters of ITO film impact the solar absorption and the infrared
emissivity of OSR. Then,based on the theoretic analysis of main antistatic parameters of ITO, including the surface
square resistance, secondary electron emission characteristic, solar absorption rate, infrared emissivity and other optical
and electrical parameters. It illustrated that those factors have a strong reverse connection with the thermal control
parameters of OSR, and influenced the solar absorption, infrared emissivity and their ratio of OSR. Comparison of the
predicted and experimental results demonstrate that when reducing the surface square resistance of the ITO film, the
antistatic properties was declined, and increased the value of the OSR solar absorption. On the contrary, reducing the
infrared emissivity, It would result in the degradation of OSR's thermal control performance. The study has performed
that the reverse association mechanism of conducting OSR can't be ignored. And apparently it shows that if we want to
keep its application in the spacecraft thermal control environment and antistatic properties long-term stable, the
antistatic parameters principles of ITO film need to be designed reasonably.
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