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Measuring Wavelength and Power 3
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3
Measuring Wavelength and Power
Limiting the wavelength measurement range 3-3
Measuring broadband devices and chirped lasers 3-4
Graphical display of optical power spectrum 3-5
Instrument states 3-6
Power bar 3-6
Limiting the wavelength measurement range
The wavelength range of measurement can be limited
with the wavelength limit function. When the wave-
length limit function is on (LIM ON), the WDM channel
analyzer has an input range from the start wavelength
to the stop wavelength. Both start and stop wave-
lengths can be chosen. The units of the wavelength
start and stop are the same as the currently selected
wavelength units. If wavelength units are later changed,
the start and stop wavelength units will change accord-
ingly. Note that a
start wavelength limit in nm will
become a stop wavelength limit if THz is chosen. See
“To change the units of measure” on page 3-7 .
The graphical display always uses the start and stop
wavelength values to plot the power spectrum, whether
the wavelength limit function is on (LIM ON) or off
(LIM OFF).
Preset turns wavelength limiting on. Only responses
that are within the boundaries of the chosen start and
stop wavelength limits are measured.
To limit the wavelength range
1 Press the
Setup
key.
2 Press the
WL LIM
softkey.
3 Press the
STARTWL
softkey to adjust the start wavelength
value and then press
RETURN
when you are done.
4 Press the
STOP WL
softkey to adjust the stop wavelength
Note
If the measured amplitudes are low, clean the front-panel OPTI-
CAL INPUT connector.