Understanding Infrared Thermography Reading 3

125. Thermogram - A thermal map or image of a target where the gray tones or color
hues correspond to the distribution of infrared thermal radiant energy over the
surface of the target (qualitative thermogram); when correctly processed and
corrected, a graphic representation of surface temperature distribution
(quantitative thermogram).
126. Thermograph - Another word used to describe an infrared thermal imager.
127. Thermometer - Any device used for measuring temperature.
128. Thermopile - A device constructed by the arrangement of thermocouples in
series to add the thermoelectric voltage. A radiation thermopile is a thermopile
with junctions so arranged as to collect infrared radiant energy from a target, a
type of thermal infrared detector.
129. Time constant - The time it takes for any sensing element to respond to 63.2
percent of a step change at the target being sensed. In infrared sensing and
thermography, the time constant of a detector is a limiting factor in instrumcnt
performance, as it relates to response time. (?)
130. Total field of view (TFOV) - In imagers, the total solid angle scanned, usually
rectangular in cross section. (TFOV=FOV?)
131. Transducer - Any device that can convert energy from one form to another. In
thermography, an infrared detector is a transducer that converts infrared radiant
energy to some useful electrical quantity.
Charlie Chong/ Fion Zhang