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OWNERS MANUAL | Cobolt 08-01 Series | D0141-K SEPTEMBER 2020
Settings Optimization in modulation mode
Cobolt Monitor™ software allow
s the user to optimize the laser performance while in modulation mode. During
manufacturing the 06-DPLs settings are optimized for digital modulation at 1 kHz and a 50% duty cycle.
Examples of the effect of modulation frequency on pulse shape. The input signal can be seen in blue and the measured 06-DPL
output signal in green. On the left a 1 kHz square wave input signal, on the right a 10 kHz input signal.
Cobolt 06-DPL modulation mode settings
When modulating with a different input signal the user can expect changes in the pulse shape, peak power and
average power.
Modulation mode temperature
(TEC_LD
mod
), High current and Low current can be adjusted to
re-optimize performance, though 100 % of the performance may not be recoverable.
The modulation settings
of Cobolt 06-DPLs are optimized at the factory with a default modulation frequency of 1 kHz. The settings can
be adjusted to optimize performance for the modulation scenario being used. The modulation mode
temperature
(TEC_LD
mod
),
high and low current settings can have strong influence on the pulse shape and can
be optimized for a particular modulation frequency. The modulation mode settings can be adjusted to optimize
the laser
’s
modulation performance in application.
Low Current
The low current defines the drive current the laser diode is set to in the
OFF
state while in
modulation mode. The default factory setting is the current just below the lasing threshold.
If the application
requires, it is possible to set the low current to
0
mA where a perfect dark state is required. Adjusting the lower
current can have adverse effects on pulse shape.
