Miniaturized gas refrigeration device with two or more thermal regenerator sections

The size of a miniature cryocooler (100) operating on the Stirling refrigeration cycle is further reduced by shortening a first thermal regenerator module (R) disposed on a cold side of a thermal barrier (T) and providing a second thermal regenerator module (R1) disposed on a warm side of the thermal barrier (T). A thermally insulated fluid flow passage (172) is disposed to interconnect the first and second regenerator modules to thermally insulate the fluid passage (172). In combination, the first and second regenerator modules provide 100% thermal regenerator effectiveness in the device.