FLIR E60 User Manual

Theory of thermography
32
• A selective radiator, for which ε varies with wavelength
According to Kirchhoff’s law, for any material the spectral emissivity and spectral absorp-
tance of a body are equal at any specified temperature and wavelength. That is:
From this we obtain, for an opaque material (since α
λ
+ ρ
λ
= 1):
For highly polished materials ε
λ
approaches zero, so that for a perfectly reflecting materi-
al (i.e. a perfect mirror) we have:
For a graybody radiator, the Stefan-Boltzmann formula becomes:
This states that the total emissive power of a graybody is the same as a blackbody at the
same temperature reduced in proportion to the value of ε from the graybody.
Figure 32.8 Spectral radiant emittance of three types of radiators. 1: Spectral radiant emittance; 2: Wave-
length; 3: Blackbody; 4: Selective radiator; 5: Graybody.
Figure 32.9 Spectral emissivity of three types of radiators. 1: Spectral emissivity; 2: Wavelength; 3: Black-
body; 4: Graybody; 5: Selective radiator.
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FLIR E60 Specifications

General

Resolution	320 x 240 pixels
Thermal Sensitivity	<0.05°C at 30°C
Field of View	25° x 19°
Battery Life	4 hours
Spatial Resolution	1.36 mrad
Image Frequency	60 Hz
MeterLink	Yes
Laser Pointer	Yes
Text Annotation	Yes
Storage Media	SD card
Spectral Range	7.5 – 13 µm
Temperature Range	-20°C to +650°C
Display	3.5" LCD touchscreen
Focus	Manual
Accuracy	±2°C or ±2% of reading
Image Modes	Thermal, visual, MSX
Voice Annotation	Yes
Battery Type	Li-Ion battery
Minimum Focus Distance	0.4 m
Operating Temperature Range	-15°C to +50°C
Storage Temperature Range	-40°C to +70°C
Connectivity	Wi-Fi, USB
Image Storage	JPEG