FLIR E60 User Manual

Theory of thermography
32
32.4 Infrared semi-transparent materials
Consider now a non-metallic, semi-transparent body – let us say, in the form of a thick flat
plate of plastic material. When the plate is heated, radiation generated within its volume
must work its way toward the surfaces through the material in which it is partially ab-
sorbed. Moreover, when it arrives at the surface, some of it is reflected back into the inte-
rior. The back-reflected radiation is again partially absorbed, but some of it arrives at the
other surface, through which most of it escapes; part of it is reflected back again.
Although the progressive reflections become weaker and weaker they must all be added
up when the total emittance of the plate is sought. When the resulting geometrical series
is summed, the effective emissivity of a semi-transparent plate is obtained as:
When the plate becomes opaque this formula is reduced to the single formula:
This last relation is a particularly convenient one, because it is often easier to measure
reflectance than to measure emissivity directly.
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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