NCJ Number
177458
Journal
Law Enforcement Technology Volume: 26 Issue: 5 Dated: May 1999 Pages: 22-26
Date Published
1999
Length
5 pages
Annotation
After describing the technologies of image intensifiers and thermal imagers, this article discusses the police uses of these two technologies.
Abstract
Image intensification systems collect available light and intensify it thousands of times to create a distinguishable image in the dark. Thermal imaging technology senses thermal radiation from the 7.5 to 13.5 micron range. A thermal imager measures these small temperature differences that cannot be seen with the human eye to create a thermal picture. In zero-light conditions, a thermal imager can create an image of a human, but an image intensifier cannot. Some officers use these devices in tandem; for example, a thermal imager can detect the presence and location of a human in the dark, and then the image intensifier makes the image clearer so that identification is possible. When it comes to the variety of uses, however, thermal imaging apparently is superior. Officers us image intensifiers in low- light situations, search and rescues, fugitive searches, and surveillance operations. On the other hand, the Law Enforcement Thermographers Association has sanctioned 11 thermal imaging uses for law enforcement and expects to add more this year. These include search and rescue missions, fugitive searches, perimeter surveillance, vehicle pursuits, flight safety, marine and ground surveillance, structure profiles, disturbed surfaces, hidden compartments, environmental hazards, and officer safety. Other emerging uses of thermal imaging are the obtaining of more accurate skid-mark measurements at a crash scene and the obtaining of evidence at a crime scene that cannot be observed with the human eye.