Detection Rating (DRI)
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.
Detection means that you will be able to see the target, however it will be little more than a speck. Specifically it means that there is a 50% chance that the target is visible on at least two pixels, and thus there is a good chance that the target is actually something of suspicion.
For a complete explanation of DRI measurements and what to expect from them, please see our Whitepaper on DRI: Thermal Distance Ratings Explained.