Glossary
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Glossary of Thermography Terms
Objective, Objective Lens
The primary lens of an optical system, On an infrared instrument, usually the interchangeable lens that defines the total field of view.
Opaque
Impervious to radiant energy. In Thermography, an opaque material is one that does not transmit thermal infrared energy, (τ = 0).
Optical Element, Infrared
Any element that collects, transmits, restricts or reflects infrared energy as part of an infrared sensing or imaging instrument.
Oversampling
Collecting samples at a rate higher than the Nyquist critical frequency, fc = 1/(2∆), where ∆ is the sampling interval. Applies to both time and spatial domains.