FLIR TG165 - Appendices and Reference Information; Emissivity Factors for Common Materials

FLIRTG165USERGUIDEDocumentIdentifier:TG165‐en‐US_AA
28
12Appendices
12.1EmissivityFactorsforCommonMaterials
12.2InfraredEnergyandImagingOverview
Athermalimagergeneratesanimagebasedontemperaturedifferences.Inathermalimagethehottestitemin
thesceneappearsaswhiteandthecoldestitemasblack,andallotheritemsarerepresentedasagrayscale
valuebetweenwhiteandblack.

Itmaytakesometimetoget
usedtothethermalimagery.Havingabasicunderstandingofthedifferences
betweenthermalanddaylightcamerascanhelpwithgettingthebestperformancefromtheTG165.

Onedifferencebetweenthermalanddaylightcamerashastodowithwheretheenergycomesfromtocreatean
image.Whenviewingan
imagewithanordinarycamera,therehastobesomesourceofvisiblelight(something
hot,suchasthesunorlights)thatreflectsoffoftheobjectsinthescenetothecamera.Thesameistruewith
humaneyesight;thevastmajorityofwhatpeopleseeisbasedon
reflectedlightenergy.Ontheotherhand,the
thermalimagerdetectsenergythatisdirectlyradiatedfromobjectsinthescene.

Material Emissivity Material Emissivity
Asphalt 0.90to0.98 Cloth(black) 0.98
Concrete 0.94 Skin(human) 0.98
Cement 0.96 Leather 0.75to0.80
Sand 0.90 Charcoal(powder) 0.96
Soil 0.92to0.96 Lacquer 0.80to0.95
Water 0.92to0.96 Lacquer(matt) 0.97
Ice 0.96to0.98 Rubber(black) 0.94
Snow 0.83 Plastic 0.85to0.95
Glass 0.90to0.95 Timber 0.90
Ceramic 0.90to0.94 Paper 0.70to0.94
Marble 0.94 ChromiumOxides 0.81
Plaster 0.80to0.90 CopperOxides 0.78
Mortar 0.89to0.91 IronOxides 0.78to0.82
Brick 0.93to0.96 Textiles 0.90