ALLIED Vision Technologies Pearleye P-030 LWIR - Manual (Page 31)

Camera interfaces
Pearleye Technical Manual V2.3.0
31
The following diagram shows the result:
Consideration of the emission ratio
Every material has its own emissivity value for IR, so the measured value is not
equal to the real temperature. The best result can be reached with materials
that have emissivity ratio near to 1.0 (100%).
The following formula allows correcting the temperature value, when the emis-
sivity ratio is known:
with:
T
t
[K]: Corrected value in Kelvin
T
m
: Measured value in Kelvin
T
b
: Background temperature in Kelvin
:
Emission ratio
Figure 9: Conversion of image data to temperature data: Pearleye P-030 LWIR
Formula 1: Emissivity correction
T
t
K
 
T
m
4
1
 –   T
b
4  – 4
 4
----------------------------------------------- =