User`s guide
Performance Tests Wavelength Accuracy
82 Agilent 81600B Tunable Laser Source Family, Fourth Edition
The mode-hop free tuning range is defined for the stepped mode. It is 
automatically ensured by the wavelength regulation performed by the 
TCFS, because the relative wavelength accuracy is better than half of a 
mode-hop. The mode-hop free tuning range can be tested manually in the 
same way as wavelength accuracy but with a higher wavelength 
resolution, as described in the following test sequence. The test is 
focussed to the beginning and the end of the tuning range where the 
probability of possible mode-hops is much higher.
At the start of the test the TLS is set:
• To (a) its lowest specified wavelength, then 
(b) 10 nm below its maximum specified wavelength,
• To the highest power the TLS can deliver over the 10 nm wavelength 
range at the beginning and the end of the tuning range,
• Such that any modulation is off,
• To tune over 10 steps with 1 nm increments.
Test Procedure
This test procedure is applicable to the:
It measures mode-hop free tuning range of the module at the outputs 
indicated.
Attenuate the Power Output from the TLS Reduce the output power 
delivered by the TLS to a level compatible with the capabilities of the 
wavelength meter.
Use the TLS module’s built-in attenuator, or an external attenuator.
NOTE
Agilent 81600B #200 (Output 2, High Power)
Agilent 81600B #160 (Output 2, High Power)
Agilent 81600B #150 (Output 2, High Power)
Agilent 81600B #140 (Output 2, High Power)
Agilent 81600B #142 #003
Agilent 81600B #142
Agilent 81600B #130 (Output 2, High Power)
Agilent 81600B #132










