Jenoptik VARIOSCAN high resolution Series Manual page 52

Temperature measurement
By varying the offset value, the user can adjust the temperature display
of the camera to the actual temperature value. As this offset acts on the
radiant power on which temperature calculation is based, unknown
fractions of extraneous radiation are easily compensated.
object
(1) Direct radiation of measured object:
ε ∗ τ
o
(2) Ambient radiation reflected by measured object:
(
− ε
1
(3) Characteristic radiation of air path:
(
− τ
1
Total radiation:
= ε ∗
P
1 o
When you switch-on the VARIOSCAN high resolution, a calibration file
is loaded containing the temperature-relevant parameters of the current
camera configuration. This file also contains the thermal characteristic
of the camera set up of 20 calibration points distributed over the entire
temperature measuring range and the corresponding conditions of
calibration. Subsequently, all other temperatures are derived by
52
environment
air path
( )
∗ λ
P T , with
P o
) ( )
τ ∗ ∗ λ
P T ,
o p A
) ( )
∗ λ
P T ,
p p
( ) (
τ ∗ λ +
P T ,
p o
2
1
3
− ∗
ap dis tan ce
τ =
1000
e
p
) (
− ε ∗ τ ∗
1 P T
o p
camera
( ) (
)
λ + − τ ∗
, 1 P
A p
)
λ +
T , O
p u