Agilent Technologies 8163A - What Is a Tunable Laser; How to Set the Power

What is a Tunable Laser ? Tunable Lasers
Agilent 8163A Lightwave Multimeter, Agilent 8164A Lightwave Measurement System, & Agilent 8166A Lightwave
Multichannel System, Fourth Edition
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What is a Tunable Laser ?
A tunable laser is a laser source for which the wavelength can be varied through a
specified range. The Agilent Technologies Tunable Laser modules also allow you
to set the output power, and to choose between continuous wave or modulated
power.
How to Set the Power
The laser output can be either:
• a continuous wave (CW) signal, fixed amplitude signal, see “How to Set the
Output Power of a CW Signal” on page 104,
• a modulated signal, see “How to Modulate a Signal” on page 119, or
• a signal with increased linewidth (coherence control), see “How to Increase
Linewidth” on page 124.
If [Mod Src] is <Off>, a continuous wave signal is the chosen optical output. A
continuous wave signal is the default.
If any other [Mod Src] source is chosen, the chosen source modulates the signal.
For possible modulation sources, see “How to Modulate a Signal” on page 119.
Attenuator If your tunable laser has an built-in optical attenuator, you can choose one of
the two following power modes:
• <Automatic> Attenuation Mode, you specify the output power and the
instrument automatically sets the optical output power by using the
optimum combination of laser diode current and optical attenuation, or
• <Manual Att.> Mode, you specify the output power and the attenuation.
The two modes are separate, the values set in one mode do not affect values
set in the other.