Gentec-EO P-LINK User Manual

Page 21

P-

LINK User’s Manual Revision 15.0

Gentec Electro

joulemeter. The only restriction is that the time delay between pulses,

Delay

Rep. Rate









, must be

more than three times the constant time of the detector. (Please refer to the instruction manual for the
specific power detector you are using.)

This command is a toggle so a checkmark indicates when it is on. Select it again to turn it off. The
default is off.

Allow at least 2 laser pulses for the auto scale to select the optimal scale for your measurement.

Keep in mind that the power detectors are optimized to sustain high average power, not high peak
energy. Always keep the energy density below the maximum energy density quoted in the manual for
that specific detector.

The single pulse energy measured in Energy Mode is precise to ±5% of the power measurement
calibration. This is larger than the uncertainty in the power measurement (typically ±2.5%) because the
energy calibration is computed from the power measurement calibration. A precision of ±3% in the single
pulse energy measurement can be achieved if the power detector head is specifically calibrated to
measure in single pulse energy mode. Please contact your local Gentec-EO distributor or nearest
Gentec-EO office for more information on obtaining a single pulse energy measurement calibration.

5.2.6 Settings - Trig Level

The trigger level is only used with a power detector head and PC-LINK is in Energy mode. This option
allows the user to change the Trigger Level in absolute values. This proves to be especially useful in
noisy environments.

To change the Trigger Level value, access the dialog box by selecting Trig Level from the Settings
menu and enter the desired number in absolute value. The P-LINK will not detect pulses with a value
under the Trig level.

The value of the Trigger level is shown in the status menu confirming that the Trigger level is activated to

a specific user level.

Selecting a high value for the trigger level may cause problems with the detection of widely varying
energy values in the Autoscale mode. The Autoscale function uses the energy level of the last pulse to
set the scale level. Therefore it will not detect the next pulses if they are lower than the trigger level. As a
result, the Autoscale may become caught on a high scale value. To solve this problem, select a lower
value for the trig level, then send the serial command *SHI. If you want to select the higher Scale, send
the serial command *SLO. To select the autoscale, send the serial command *FAS.

Erratic triggering?

For a few detector heads, in electrically noisy environments, it is possible that the P-LINK will
inadvertently trigger on the noise. In that case, increase the trigger level..

5.2.7 Settings - Anticipation

Thermal power detectors are inherently slow. The P-LINK uses an algorithm to significantly accelerate
the response. This is called “anticipation”. By default, this option is enabled. The reasons for disabling
the anticipation are to slow down the response and to lower the noise level. Anticipation is not used in
energy mode.