RayTek ThermoView Ti30 - Manual (Page 80)

Non-Gray Body
A radiating object that is partly transparent to infrared (transmits infrared energy at certain
wavelengths); also called Colored Bodies. Glass and plastic films are examples of non-gray
bodies.
Optical Pyrometer
A system that, by comparing a source whose temperature is to be measured to a
standardized source of illumination (usually com-pared to the human eye), determines the
temperature of the former source.
Optical Resolution
The distance to size ratio (D:S) of the IR measurement spot, where the distance is usually
defined at the focus distance, and the size is defined by the diameter of the IR energy spot at
the focus (typically at the 90% IR energy spot diameter). Optical resolution may also be
specified for the far field by using values of far field distance and spot size.
Pyroelectric Detector
Infrared detector that behaves as a current source with an output proportional to the rate of
change of the incident IR energy.
°R (Rankine)
Temperature scale where , or also .
K 8 . 1 R u q 460 F R  q q
Radiation Thermometer
A device that calculates an object’s temperature (given a known emissivity) from
measurement of either visible or infrared radiation from that object.
Recall (RCL)
When the Recall loop is activated, stored values can be recalled from either the RUN or
LOG loops.
Reflectance
The ratio of the radiant energy reflected off a surface to that incident on the surface; for a
gray body this is equal to unity minus emittance; for a perfect mirror this approaches unity;
and for a blackbody the reflectance is zero.
July 1, 2003 - 80 - Version 1.0
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