Joule-Thomson cryostat cooled infrared cell having a built-in thermostat sensing element

摘要: A cryogenically cooled infra-red detection cell assembly comprises a Dewalask type of thermal insulation casing. The closed end the Dewar casing is front and adapted to have lead sulfide transducer mounted on inside face inner wall, outer wall form part lens system for focusing transducer. Joule-Thomson cryostat projects into so as maintain liquid nitrogen adjacent outside wall. mass absorbent packing placed in its end, just ahead cold retain there. metal mandrel, with rear mandrel serving mount small piece gold-doped germanium. This doped germanium acts variable resistance at critical range temperature control cryostat, operatively connected thermostat circuit which actuates valve controlling flow gas cryostat. electrical connections consist conductive strips extend rearwardly along surface lateral Shieldings prevent microphonics due vibration, motion are deposited surfaces walls