Development of a 5 to 20 W at 80 K GM Pulse Tube Cryocooler

In order to select the most suitable phase shifting mechanism for the GM pulse tube coolers applied to cryoelectronic devices, we evaluated the performance of both double-inlet and four-valve type phase shifting mechanisms by using a single-stage GM pulse tube cooler and an on-off timing control system designed for valved cryocoolers. The lowest temperature achieved was 29.1K and the largest cooling capacity at 80K and 60K was 13 and 10W, respectively. For the four-valve type cooler, the cooling capacity at 80K was 72% of that for the double inlet type cooler.