9-3
IM AQ1200-01EN
Optical Power Meter (Option)
3
2
1
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
App
Index
20
Explanation
This feature is available on models with the /SLT, /HLT, /PPM or /SPM option.
Wavelength
The light receiving element of the optical power measurement section has a wavelength sensitivity
characteristic. The Instrument measures optical power more accurately by adjusting the sensitivity
according to the specified wavelength.
Models with /SLT, /HLT or /SPM option
The wavelength ranges and steps vary depending on the wavelength mode that you set in the
detailed setup screen. You can set the wavelength within the following ranges.
Wavelength Mode
Range and Steps
Simple
You can select from 850 nm, 1300 nm, 1310 nm, 1490 nm, 1550 nm, 1625 nm, and
1650 nm.
Detail
You can set the wavelength to a value from 800 to 1700 nm in 1 nm steps.
CWDM
You can set the wavelength to a value from 1270 to 1610 nm in 20 nm steps.
Models with /PPM option
You can set the wavelength to one of the following values.
1310 nm, 1490 nm, 1550 nm
Modulation Mode
You can set the modulation mode for optical measurement to one of the following options.
CW (continuous light), 270 Hz, 1 kHz, 2 kHz
Unit
You can set the optical power display unit to one of the following options.
dB (relative value), dBm (absolute value), W (absolute value)
• The following
prefixes are attached to W: m (10
–3
), μ (10
–6
), n (10
–9
), and p (10
–12
).
• The relationship between the absolute values dBm and W is indicated below.
P
dBm
= 10 × log (P
w
× 10
3
)
Where P
dBm
is the optical power in units of dBm and P
w
is the optical power in units of W.
Reference
You can set a reference and display measured values as relative values (display their difference from
the reference).
• Press the DREF soft key to make the displayed measured value the reference and display
subsequent measured values as relative values. The unit will change to dB.
• Press the DREF soft key or set the unit to dB to display the Reference box in the Power Meter
screen.
• You can set the reference manually in the Reference box. The range is –80 to 40 dBm.
• If you set the unit to dBm or W, the Reference box disappears and the measured values are
displayed as absolute values.
Wavelength Mode
You can set the mode to one of the following options.
Simple, Detail, CWDM
When you change the wavelength mode, the wavelength range and steps for the Wavelength item
change as explained above.
Average Count
Averages of the measured values are displayed. You can set the number of values to average to one
of the following options.
1, 10, 50, 100
9.2 Setting Optical Power Measurement Conditions and Holding the Display
