Fresnel lens radiation shield for photodiodes

Recently, since space satellites use image sensors and photodiode sensors, their radiation tolerance has become an important concern. In addition, some available space communication systems use a photodiode sensor for communications. However, since such sensors have an aperture without shielding, the total ionizing dose tolerance of the sensors becomes so weak that the radiation tolerance becomes lower than that of other embedded components. This paper therefore presents a proposal of a Fresnel lens radiation shield for use with photodiodes. A Fresnel lens can increase the light sensitivity and radiation tolerance of a photodiode.