What is stirling microcooler?

Answer 1

A sterling micro cooler is a small device typically used in thermal imaging devices. It operates on the principle of an alpha type sterling engine (two seperate cylinders.) that is powered by a small dc motor.

Most hobby type sterling engines are powered by heating the hot cylinder with an external heat source. The temperature differential between the hot and cold cyclinders being what cycles the mechanism and spins the flywheel.

In a microcooler application, the sterling engine is powered by a dc motor that cycles the mechanism, thus creating a temperature differential between the two cyclinders. The hot side tends to resemble a heat sink or the cylinder of an air cooled internal combustion engine, it is the bulkier part of the device and sports many cooling fins. The cold side is a thin rod. When the infrared detector is mounted to the cold side, the rod goes inside of it to cool it internaly.

This cools the ir detector sufficiently to give it resolution required to produce an IR image. Some IR cameras are not cooled, but most with a range of more than 4 feet or that need higher quality video output are cooled with sterling coolers that are sealed and use Helium as the gas medium.