Agilent Technologies 86120C, User Manual

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2-9
Making Measurements
Measuring Wavelength and Power
Measuring broadband devices and chirped lasers
When first turned on (or the green Preset key is p ressed), the
Agilent 86120C is configured to measure narrowband devices such as
DFB lasers and modes of FP lasers. If you p lan to measure broadband
devices such as LEDs, op tical filters, and chirp ed lasers, use the
Setup
menu first to reconfigure the instrument. When broadband devices are
selected, the display shows the
BROAD annotation on the screen.
The measurement algorithm for broadband devices determines the
wavelength based up on the center- of- mass of the p ower sp ectrum. The
peak excursion function is used to determine the value of the integra-
tion limits. Care must be taken to ensure that the integration limits
are above any noise. This is especially true when measuring devices
with slop ing noise floors, like an EDFA amp lifier. For more informa-
tion on peak excursion,
refer to “Defining Laser- Line Peaks” on p age
2- 15 .
Instrument specifications apply when the Agilent 86120C is configured
to measure narrowband devices. Specifications do not apply when the
instrument is configured to measure wideband devices.
To measure broadband devices
1 Press the Setup key.
2 Press MORE twice, and then the DEVICE softkey.
3 Press the BROAD softkey.
To return to measuring narrowband devices, p ress NARROW .