To be clear on the terms used.... A cryo cooled TIC cools the detector to an insane approx. -200 Degrees Celcius. It does this with a Stirling engine cooler charged with Helium. Many have asked the question whether such a mechanical cooler could be replaced with a Peltier stack. Sadly the answer is no. The losses and physics of the Peltier stack preclude such a temperature differential at normal ambient levels on earth. I used to use Liquid Nitrogen in cameras so the Stirling cooler is a great step forwards compared to that. The maintenance cost and noise generated by the cooler are the two big drawbacks to cryo cooling, not to mention the high power consumption.
The 'uncooled' detector is called such because it does not need to be cooled to cryogenic temperature levels in order to produce useful data. The Cryo cooled detectors produce nothing useful at ambient temperatures due to their internal heating and noise. The cryogenic temperatures reduce such to levels where by the output is actually lower noise than a micro-bolometer. For scientific work Cryo-cooling is often the way to go.
The large down side to micro-bolometers is that they are basically an array of thermistors. As many will know, thermistors are used as temperature sensors as they change value with temperature. The problem is, the temperature inside a TIC changes and the die of the micro-bolometer also includes electronics that produce heat. This all adds up to a micro-bolometer that has pixel outputs straying all over the place without an image presented to them. To 'tame' the micro-bolometer, it is actually HEATED to 30 degrees Celcius and held at that temperature by a Peltier module. If the die gets too hot, it is cooled, if it gets too cool, it is heated. It is not, however considered to be a 'cooled' detector, just temperature stabilised.
Not all semiconductor based thermal imaging arrays need to be Cryo cooled. The BST detector array is such a device. These predate the Micro-bolometer and some may say they are superior. They fell behind in development when the US Govt pulled the funding. Micro-bolometers were the 'new tech' and the US Govt put the funding into that, and developed it into what you are using today. It must be remembered that this technology originally had two major uses....an aid to fire fighters rescuing people in dense smoke, and an aid to killing your enemies on the battlefield ! It is an odd world we live in but warfare and Military matters often lead to investment in technology and its rapid advancement which hopefully benefits many.
I hope this helps to explain the situation a little clearer.
The current needed to control the die temperature is not as much as you might think. The die's thermal mass is low. The Peltier module wires on my Microbolometer are actually quite thin. I will add a photo. They are the white ptfe insulated wires in the image. The PM695 draws around 1A when operating and she is an old girl in comparison to the E series, full of power hungry discrete IC's and motors ! The Peltier module normally only has to compensate for die self heating and small changes in ambient and at 30 Degrees is only around 10 degrees or so above comfort level for humans. I you take it to the Arctic or somewhere else cold, it is a different matter
it will have to work harder so battery life may be reduced.
Please look at the attached Patent document that shows the construction of micro-bolometers.
Also, please take a look at the document that is found here: (Chapter 4)
http://archives.njit.edu/vol01/etd/1990s/1997/njit-etd1997-027/njit-etd1997-027.pdf
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