Detection, Recognition, and Identification (DRI) are guidelines that have been set in place by The Night Vision Thermal Imaging Systems Performance Model, also referred to as the Johnson criteria. They are a universally accepted set of standards developed by the US Army to provide a means of measuring the distance whereby a thermal sensor can produce an image of a specific target.
Contrary to what might be expected, recognition does not mean that you can recognize a person. Recognition simply means that you are able to recognize an object’s class (is it a human or a car, is it a truck or a tank, etc).
For a complete explanation of DRI measurements and what to expect from them, please see our Whitepaper on DRI: Thermal Distance Ratings Explained.