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Focus Point (or Distance)
The distance from the instrument where the optical resolution is greatest.
Full Scale
The maximum of the temperature range or output signal.
Full Scale Accuracy
A convention for expressing the accuracy as percentage of an instrument’s (highest) full- scale temperature.
Gray Body
A radiating object whose emissivity is in constant ratio (not unity) at all wavelengths to that of a blackbody at the same temperature, and does not transmit infrared energy.
HAL
High Alarm. Units with this feature can sound an alarm when they sense that a
Hertz (Hz)
Units in which frequency is expressed. Synonymous with cycles per second.
Infrared (IR)
The portion of the electromagnetic spectrum extending from the far red visible at approximately 0.75 µm, out to 1000 µm. However, because of instrument design considerations and the atmospheric windows, most infrared measurements are made between 0.75 µm and 20 µm.
Infrared Thermometer
An instrument that converts incoming IR radiation from a spot on a target surface to a measurement value that can be related to the temperature of that spot.
K (Kelvin)
The unit of absolute or thermodynamic temperature scale where 0 K is absolute zero and 273.15 K is equal to 0° C. There is no (°) symbol used with the Kelvin scale, and
KθC 273.15 .
July 1, 2003 | - 78 - | Version 1.0 |
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