Thermal Imaging Cameras, Thermal Imagers, Imaging Radiometers, Infrared Cameras, Image Intensifiers

There are many terms used to describe Infrared Imaging Radiometers, but care should be taken to discern exactly what one is talking about.* There are indeed many different types of technology when it comes to infrared.* That which is most often confused with thermal cameras are night vision cameras which typically utilise image intensifiers or near infrared illumination.** Image intensifiers*amplify the available light to achieve better vision, and because of this some light is required.****With Near Infrared illumination, we use*a common CCD device*that is sensitive to invisible near infrared radiation*used in conjunction with an infrared illuminator.* These methods are often loosely referred to as infrared cameras (because of the use of a near infrared illuminator) but neither actually measure in thermal*part*of the spectrum.
Then we get to the real “infrared” cameras, which should be more correctly termed by their capability.* Those systems which are capable of measuring temperature we refer to as radiometers.* It would be correct to refer to these as*an “Infrared Imaging Radiometer” or perhaps a “Thermal Imaging radiometer”.* We use the term “imaging” to differentiate from those which are single point devices (ie that give one temperature point) as oppossed to an image full of discrete measurements.* A thermal imager or infrared camera may be a thermal device, but one incapable of temperature (radiometric) measurement, such as a those used by the military or for surveillance applications.