Our system has one of the highest array sizes, i.e. resolutions (ours is 640×480 compared to the more common 320×240). This allows us to capture a broader screening area (both height and width) than most systems. This also allows us to have a more favorable Instantaneous Field-of-View, or IFOV (the angle subtended by a single detector element). This matters because our system scans a very specific part of the face (inside corners of the eyes, as described below), and if the IFOV is too large, other (cooler) parts of the face will get mixed in, resulting in a higher rate of missed detections.
Our cameras are inherently accurate, meaning no external blackbody source is required. We accomplish this through extensive in-house calibration. Blackbody setup can skew temperatures if the blackbody is not angled, positioned, or calibrated properly, as well as if temperature drifts due to environmental factors. By avoiding the need for a blackbody, we avoid this potential performance issue. Additionally, we provide mid-use touch-up of our detectors using shutter-based calibration to maintain a high degree of radiometric consistency and uniformity.