ACHIEVING THE DEEP CRYOGENIC BACKGROUND ENVIRONMENT OF SPACE CRYOGENIC OPTICAL EXPERIMENT

In order to get the deep cryogenic background conditions of space cryogenic optical test,it discussed achieving deep cryogenic environment simulation technology and helium cooling system.It's analysed that 20K stable deep cryogenic cold and black background established by helium circulating is the most suitable cryogenic optical test Environment.The system is a closed circulatory system,which is composed of the helium liquefaction system with corresponding cold helium assigned device and the terminal cold cabin.Helium liquefaction system is based on the Claude cycle,that is composed of Brayton cycle and Joule-Thomson effect.It can continuously provide the liquid helium with a certain flow and pressure or cold helium as cycle refrigerant,and supply a stable deep cryogenic environment for the experiment.