Closed-cycle mechanical cryogenic refrigerators, or cryocoolers, are an enabling technology for next generation
infrared (IR) sensors. Passive cryoradiators and stored cryogen systems have been used successfully in the past, but the
increased cooling requirements for emerging systems cannot practically be met with these passive techniques. Modern
systems are employing much larger focal plane arrays that dissipate more energy and have higher parasitic thermal loads
than in the past. Additional "on chip" FPA data processing capability, such as time delay and integration (TDI) and
analog-to-digital conversion (ADC), is further driving up the heat loads. While loads are going up, temperatures are
going down. The desire to operate at long wave infrared (LWIR) wavelengths (>9 microns) for a broader range of
remote sensing missions is driving the need for 35-40 K refrigeration, significantly colder than past systems that operated
at shorter wavelengths. Unfortunately, the use of a mechanical rather than passive cryocooler introduces an additional
jitter source that must be properly mitigated. Techniques include the use of inherently low vibration cryocoolers, closedloop
active vibration cancellation servo systems, damping struts, soft mounts, or a combination of these techniques.
Implementation of these techniques within a proper system engineering context is presented.