HOT cooled infrared detector is a high focal plane working temperature infrared detector. In 1985, C.T. Elliott first proposed the concept of using non-equilibrium mode to increase the operating temperature of photon detectors, that is, high operating temperature (High Operation Temperature) infrared photonic devices. In 1999, C.T. Elliott discussed the conditions required to reduce the noise of photon detectors to the background level and believed that removing the cryocooler was achievable, but the technological level was difficult to achieve. In 1999, Donald first proposed that the third generation of infrared cooled infrared detectors should have the characteristics of high performance, low cost, and high operating temperature.
Some people may ask, since we already have high-performance cooling infrared detectors, why do we still need to build this HOT infrared detector? This is about the advantages of HOT infrared detectors.
In the field of infrared thermal imaging, HOT cooled infrared detectors comply with the SWaP concept generally pursued by the industry. Modern optoelectronic systems are gradually developing towards smaller sizes, lower power consumption, and lower costs. High operating temperatures can reduce the cooling capacity requirements of infrared chips, which can reduce the size, weight, cost, power consumption, and cooling time of components.
The HOT infrared detector has a higher signal-to-noise ratio (imaging quality). The development of HOT infrared detectors is the mainstream technical route for optimizing SWaP. The most critical one is to suppress the dark current of the detector, because dark current is the main culprit of noise generated by the device. For this reason, HOT infrared detectors mainly use mercury cadmium telluride and type II superlattice as basic materials. In the figure below we compare the temperature dependence of dark current in standard cooled detectors and HOT detectors. It can be found from the figure that when the dark current is the same, the temperature of the HOT detector is higher than the standard detector; when the temperature is the same, the dark current of the HOT detector is smaller than the standard detector. Therefore, we can conclude that the HOT infrared detector can maintain low dark current when the temperature is higher, and its imaging quality is better.
In the 21st century, European and American infrared detector R&D manufacturers have successively launched HOT infrared detector components. Nowadays, GSTiR also has its own HOT infrared detector: C1010 high temperature medium wave cooling infrared detector. Everyone is welcome to come for consultation.