EMCCD Tutorial

Q7 Why is a vacuum seal important?

For a high-end EMCCD to operate reliably it must be kept in a very high vacuum. The outgassing that occurs in cameras built to other non-vacuum designs, such as housing of the sensor within an o-ring sealed enclosure that is ‘back-filled’ with inert gas, can result in reduced cooling performance, QE degradation and even complete sensor failure. This danger is particularly prevalent for back-illuminated sensors, which are much more exposed to harmful moisture and volatile organic condensates. In fact, it can be considered vital that back-illuminated sensors are housed in vacuum enclosures. The motivation for some manufacturers to offer such high-end sensors in unsuitable non-vacuum designs is fairly transparent, in that it can cost notably less to build a camera to this reduced design specification! For a ‘tier-one’ EMCCD, insist on a proven vacuum enclosure….or demand a very, very good discount.

Click here to read a tech note which explains why a hermetic vacuum seal is important