System considerations in the design of QWIP-based thermal imager

We discuss the possible applications that may suit the new QWIP detector technology. We identified the tactical, mid-end land applications as a suitable application field in which QWIP detectors have a good chance of becoming a competitive option for thermal imager users. The effects of microscan and the capacitor size on the system performance were studied and we found the former to be more important than the latter, since the typical QWIP system is basically resolution limited and not sensitivity limited. Additionally, we have devised a preliminary semi-quantitative model as an aid in the task of optimizing system parameters such as field of view, F/# and QWIP temperature. The model aims at pointing to the set of parameters which will maximize the user benefit while keeping the system’s cost to a necessary minimum. Using this model we found that optimal cost-effectiveness will be achieved for a horizontal field of view of 2.5 to 3 degrees and F/# of about 2.