OWNERS MANUAL | Cobolt 06-01 Series | D0136-K DECEMBER 2018
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TEC LD
mod
Adjustment
The 06-DPLs optical output power is influenced heavily by
the match between the pump diode’s emission
spectrum and
the laser crystal’s gain spectrum
. Modulation mode operation is achieved by direct modulation of
the drive current to the pump diode. Decreasing the ON time and thereby the diode temperature, must be
compensated by an increase in the platform temperature to maintain a constant pump diode wavelength.
TEC_LD
mod
is a ‘virtual TEC’ used to control the platfor
m temperature when in modulation mode and can be
used to optimize the temperature of the pump diode. Adjust the TEC_LD
mod
temperature inversely with duty
cycle.
Thermal compensation for wavelength shift in modulation mode
High Current Adjustment
It is not always sufficient to increase the TEC_LD
mod
temperature to achieve maximum average power. When
necessary the High current level can be increased up to as much as 3000 mA, the maximum safe operating
current for 06-DPLs as set at the factory.
Low Current Adjustment
If the application requires, it is possible to set the low current to
0
mA where a perfect dark state is required, but
adjusting the lower current can have adverse effects on pulse shape.
