4-6
IM AQ6360-02EN
4.4 Inspection of Level Accuracy
Perform a check of the instrument’s level accuracy.
Use a light source of 1310 nm or 1550 nm.
AQ6360
Light source
Optical power meter
9.5/125 µm SM optical fiber
Procedure
1.
Connect the light source and instrument with a 9.5/125
µ
m SM optical fiber and
turn the light source ON.
2.
Tap
. The Main Menu window appears.
3.
Tap
SWEEP
and then
Auto
on the function menu.
Auto measurement of the light source spectrum starts. When auto measurement
is complete, repeat sweep starts automatically.
4.
Display the Main Menu window, and tap
SETUP
.
5.
Tap
Resolution
on the function menu, and set the instrument’s wavelength
resolution to 0.1 nm.
6.
Display the Main Menu window, and tap
PEAK SEARCH
. The waveform peak
level will be measured.
7.
Remove the SM optical fiber from the instrument and connect the light source to
an optical power meter.
8.
Use the optical power meter to measure power values of the light source.
9.
Check that peak level values obtained in step 6 agree with the ones obtained by
the optical power meter (within the specified level accuracy). For information on
level accuracy, see chapter 5, “Specifications.”
Note
• For the light source, prepare a line spectrum light source such a gas laser or DFB-LD. If a
wide spectrum light source is used, the power measurements may not be accurate.
• The level measurement error of the instrument changes as shown in the figure below,
according to the numerical aperture (NA) of the optical fiber connected to the input
connector. The instrument’s absolute level is calibrated using a 9.5/125 μm single-mode
optical fiber (SSMA type in JIS C6835, with PC polishing, 9.5 μm mode field diameter, and
0.104 to 0.107 NA). Even if a single-mode optical fiber is used, the level accuracy will be
outside the specifications if the NA is not in the range shown above.
