FLIR TG165 - FLIR TG165 Distance-to-Spot Ratio (24:1)

FLIRTG165USERGUIDEDocumentIdentifier:TG165‐en‐US_AA
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4.3IRThermometerDistance‐To‐SpotRatio(24:1)
Basics
TheTG165Distance‐to‐Spotratio(D:S)is24:1.Fromadistanceof24”theTG165measurestheaverage
temperatureofaspot1”indiameter.Fromadistanceof48”thespotdiameteris2”andfromadistanceof72”
thespotdiameteris3”.Thetemperatureisshown
atthetopleftoftheTG165display.
ThermometerLens
InFig4‐1,thelens’fieldofviewisrepresentedbythegreendottedlinesemanatingfromthethermometer
lens.Thisfieldofviewisangled0.04
o
.Thespotsizes(greencircles1,2,and3”indiameter)areshowninFig4‐1
atdistancesof24,48,and72”.Twoviewsofthetargetspotsareshown:targetspotsasseenfromtheside,
andtargetspotsasseenfromtheuser’sperspective(pointingat
thetargetspotswithTG165inhand).
LaserPointers
TheLaserpointerlensesareshownasred(rightsidelens)andblue(leftsidelens)coloreddots.Theselenses
arehorizontaltooneanotheronthemeterbut,asthemeterismovedawayfromthetarget,theLaserbeams
rotatecompletelyverticalsoastocreatea1”spot
atadistanceof24”.Atadistanceof48”,theLasersrotate
further(2and8o’clockpositions)sothatthespotdiameteris2”.Thebeamsremainatthispositionforfurther
distances(comparethebeamrotationsat48”and72”).
DisplayCrosshairs
ThedisplaycrosshairsrepresentthetargetspotthattheIRThermometerlensissensing.
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Fig4‐1DistancetoSpotratioandtherotatingLaserpointerbeams