3-81
Function Reference
Select Path INT/EXT
Select Path INT/EXT
For 86144B/86146B only.
Allows you to select between internal (50 µm) and external (9 µm) fiber. The
dual fiber outputs from the monochromator allow the instrument to have
improved resolution bandwidth and dynamic range when using the 9 µm fiber.
The 50 µm fiber is the default setting.
Internal (50 µm) path resolution bandwidth include: 0.06, 0.1, 0.14, 0.2,
0.33, 0.5, 1, 2, 5, 10 settings
External (9 µm) path resolution bandwidth include: 0.04, 0.06, 0.1, 0.14,
0.2, 0.33, 0.5, 1, 2, 5, 10 settings
Key Path Bandwidth/Sweep > Select Path
Remote
Commands INSTrument:SELect “FILTER”
Sensitivity
Requests the lowest amplitude signal that can be measured relative to the
power at “top of screen”. It is defined as the signal that is six times the RMS
noise. The minimum setting is –100 dB. An error will be reported for values
outside of this range and the sensitivity will round to the nearest valid se nsitiv-
ity. See “Setting the Sensitivity” on page 2-9
Manual allows manual input of sensitivities and enables auto gain ranging.
The “top of screen” and the sensitivity setting determines the requested
dynamic range. The system will sweep once per gain s tage and may require up
to three sweeps to achieve the requested dynamic range.
Auto automatically chooses a sensitivity and a single gain ran ge base d on “top
of screen”. This will result in approximately 40 dB of dynamic range.
The sweep time (ST) that is displayed in the lower portion of the displ ay is the
time for the OSA to sweep over one gain stage. The OSA may take up to three
sweeps in three different gain stages to make the measurement. This de pends
on the settings for sensitivity, reference level, auto range and also the particu-
lar device being measured. The final data trace is a blended co mpos ite of eac h
trace taken in the different gain stages. For more informa tion refer to “Setting
the Sensitivity” on page 2-9.