then multiply, or add, to the actual measured value to calculate the corrected
value. The 841-P-USB will then display the corrected value.
Figure 2.8 User Offset dialog box.
For example, if you are measuring a laser beam passing through the 99.9%
back reflector of a laser (giving 1/1000
th
of the real value), choose
Multiplier
#1
and enter 1000 in the dialog box. The 841-P-USB will display the laser’s
actual power rather than the measured 0.1% sample on the main display.
When a correction factor is active the “Head” value will be different from the
displayed measurement. The corrected measurement appears in the top left
of the screen.
It is also essential to make sure that the actual measured value complies with
the power and energy limits of the detector head.
Note that the
Statistics
are computed for the corrected values only.
To disable the correction factor, re-select the Correction Factor (multiplier,
offset) in the
Corrections submenu
of the
Settings menu
. Then select
None
in that submenu.
2.3.2.4 Power Unit
By default, the measurement unit is Watt. The
Power Unit
setting allows to
select Watt or dBm for measurements
2.3.2.5 Energy mode
This feature allows the measurement of the energy contained in a single pulse
with an
818P-Series High Power Detector
. This mode of operation gives
access to the same options as when using an 818E-Series Energy Detector.
The only restriction is that the time delay between pulses,
Rate
Rep.
Delay
1
must be more than three times the time constant of the detector. (Please refer
to the instruction manual for the specific power detector you are using.)