Volume 4, Number 2 May/June 1996
A revolutionary portable infrared camera developed by NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif., could allow doctors to detect tumors through heat analysis and enable defense forces to identify rockets by their plumes.
The one-of-a-kind camera, which uses a large focal plane of quantum-well infrared photodetectors or QWIPs that are so sensitive they can detect heat in the eight to nine microns range, was developed at JPL's Center for Space Microelectronics Technology in partnership with Amber, a Raytheon company, in Goleta, Calif.
The camera's QWIPs allow it to see radiation at wavelengths not normally visible to the human eye because the objects' infrared glows are considered to be cold. No other portable infrared camera has been developed that can see and record objects that give off wavelengths to this extreme of the infrared spectrum. The QWIP technology has been developed over the past six years for observation satellites under a contract managed by NASA's Office of Space Access and Technology.
The higher sensitivity of the camera's QWIPs makes it viable for a number of uses including detecting tumors, identifying rockets by their plumes and allowing pilots to make better landings, said Development Team Leader Dr. Sarath Gunapala of JPL.
Gunapala explained that the camera could detect tumors close to a patient's skin due to a change in the heat pattern of the patient's blood circulation. Ballistic Missile Defense Organization, using this same camera could identify launched rockets because the camera can see the rocket's cold body as it is surrounded by its hot plume. The recorded temperature difference identifies the rocket's type. Airplanes equipped with the cameras would be able to see the landing strip in total darkness or dense fog so that their pilots may make more precise landings.
Other uses include pollution monitoring, weather detection, law enforcement and search and rescue operations.
Infrared light detectors must be kept very cold if they are to work. The new camera contains a Stirling cooler, a closed-cycle refrigerator about the size of a fist. The small motor cycles cooling gas millions of times and cools the camera from room temperature to very low temperatures (-343 degrees Fahrenheit) in about 10 minutes. Still the camera weighs just less than 10 pounds and is about 4.5 inches wide, 10.5 inches deep and 7 inches high. The camera's current prototype plugs into a 110-volt wall socket for power, although it may be powered by batteries to make it portable.
For more information, contact Tim Brice at Jet Propulsion Laboratory. Phone: 818/354-4426, E-mail: timothy.m.brice@jpl.nasa.gov Please mention that you read about it in Innovation.
