A miniature pulse tube refrigerator reaching temperatures below 100K h
as been developed. In this paper the test results of the refrigerator
are reported. The refrigerator is a orifice pulse tube refrigerator. I
t is based on a miniature Stirling refrigerator. It consists of a comp
ressor, a cold head and a reservoir. The features are high operating f
requency and compact size. The lowest temperature is achieved to 98K.