The Study On Radiation Effect Of Optocoupler

Optocoupler with small volume, long life-span and stronganti-electromagnetic interference capability, etc is now widely used in satelliteoptical communication systems, as one of the key components in satellite opticalcommunications. All of the devices that work in space should take account of theradiation effect because of the radiation environment of space. So the research onthe radiation effect of optocoupler and how to protect the device from the radiationis very important. But the study of space radiation effect on optocoupler is not yetmature currently, therefore it’s necessary and urgent to study deeply on spaceradiation effect of optocoupler.The working principles of optocoupler and space radiation damage have beenanalyzed. The carrier concentration, minority carrier lifetime and diffusion lengthhave been discussed. The radiation damage on optical power of light emittingdiode (LED), current of phototransistor and current transfer ratio (CTR)ofoptocoupler have been deduced. The radiation damage models of LED,phototransistor and optocoupler have been established. This is one of theinnovations of this paper.The radiation experiment of optocoupler has been carried out. Theexperimental results such as optical power of LED, current of phototransistor andthe CTR of optocoupler have been analyzed. The experimental results andtheoretical model have been compared, which verify the correctness of thetheoretical model. The long-term annealing effects of all devices have beenobserved, which is one of the innovations of this paper.On this basis of the above study, the radiation-hardening design of optocouplerhas been proposed, which provides a reference for its space applications.