Tektronix OM4006D, Руководство пользователя

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Operating basics
If the lasers are used in conjunction with the OM4000 instrument and OUI, the
laser usage type needs to be set using the dialog on the lower right corner of each
laser panel. The OUI uses the setting to determine from which laser frequency
information is retrieved. A usage type can only be selected once between all
of the tabs but you can have one usage type on one tab and another usage type
on a second tab.
NOTE.
Only the Reference laser selection is important to OUI operation. The
other selections are to help identify which laser is which.
Once laser emission is On, the channel 1 and grid spacing settings become
read-only and cavity lock becomes editable. Also the power goes from “off” to
the actual power being read from the laser. Readings are taking from the laser
once per second.
The receiver gauge (shown at the bottom of the LRCP window) is only
active for equipment that have the appropriate hardware present (such as the
OM4000 instruments). The receiver gauge, when active, displays the total
photocurrent.
Setting laser parameters
NOTE.
For all text fi eld entries it is necessary to click away from the fi eld, or press
the Tab key, for the value entered to be accepted by the application.
CAUTION.
LRCP does not save the state of any hardware settings. The hardware
keeps the settings until that hardware is turned off. After turning on the hardware
again, all settings return to their default state, including emission (which is Off).
Channel : Type a number or use the up/down arrows to choose a channel.
The range of channels available will depend on the type of laser, the First
Frequency, and the Grid. The
fi ner the Grid, the more channels are available
for a given laser. The channel range is indicated next to the word Channel.
The laser channel can also be set by entering a wavelength in the text box to
the right of the channel entry. The laser will tune to the nearest grid frequency.
Cavity Lock : The Intel/Emcore ITLA laser that is included in the
OM4000 instrument has the ability to toggle its channel lock function.
Ordinarily, Cavity Lock should be checked so that the laser is able to tune and
lock on to its frequency reference. However, once tuning is complete and the
laser has stabilized, this box can be unchecked to turn off the frequency dither
needed for locking the laser to its reference. The laser can hold its frequency
for days without the bene
fi t of the frequency dither. The OM4000 software
will work equally well with the Cavity Lock dither on or off.
OM4000D Series Coherent Lightwave Signal Analyzer 21