OPHIR vega User Manual page 77

against. It is not necessary to do this procedure again
unless the Vega is used with a different sensor. If the
procedure is not done, errors of 2% or so can occur. To
zero the sensor against the Vega, proceed as follows:
Make sure the sensor is in a quiet environment and not
subject to pulsed radiation. Plug the sensor into the Vega
and turn on. Select "Menu" and enter. Select "Zero" and
enter. Press "Start". When "ZEROING COMPLETED"
appears, press "Save", and "Exit".
6.4.1.2. Energy Measurement
1. Ordinarily, when the instrument is switched on, it is in
the main energy measurement mode. This can be
verified by the units of mJ, µJ etc. and the legend
"Energy" in the upper right corner of the display (see
Figure 6.1). If it is in power measurement mode with
units of mW, W etc., then press "Energy".
2. Enter "Range" and select the proper range. The
correct range is the lowest one that is larger than the
pulse energy measured. If you want this to be the
default, press "Save" or return to main screen by
pressing the Enter key.
3. Press the menu button, select "Configure" and press
the Enter key. Select "Max Pulse Len" and "Diffuser"
if applicable and set to the correct value for your
laser. (See section 6.2.2.1 for further details on laser
pulse width).
4. If you wish to display the average of a number of
pulses, select "Menu", enter and select "Configure"
and enter again. Select "Average" and set to the
value desired. The default value is "NONE" which
means that the pulses displayed are individual pulses
with no averaging. See section 6.2.2.2 for further
information on averaging.
The Vega is now ready to measure energy pulses. The
energy reading will operate in the following manner. If
"NONE" selected as the averaging period, following every
1/5th of a second period, the Vega will display on the
screen the next pulse which arrives. The Vega will hold
the display of the latest pulse until a new one arrives. If
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