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OWNERS MANUAL | Cobolt Modulated DPSS Lasers | D0342-C JUNE 2016
Plot of typical optical output power as function of the applied analogue voltage. There is a device specific maximum.
Digital modulation
In pure digital modulation, the applied analogue voltage determines the on-state optical output power in accordance
with the plot above. E.g. if the amplitude of the digital modulation should be maximized, the analogue voltage
corresponding to the maximum output power should be applied. In this way, the on-state optical power in digital
modulation can be controlled.
An digital modulation
The analogue and digital modulation described above can be combined where the digital modulation can be seen as
a control signal that can switch the analogue modulation on and off. The principle is schematically illustrated in the
figure below.
Schematic illustration of the three different modulation modes.
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Voltage on analogue input (mV)
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Analogue input voltage
Digital input voltage
Optical output power
Analogue modulation
Digital modulation
An Digital modulation
