Keysight Technologies 86120B, User Manual

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Programming
Example Programs
Example 6. Increase a source’s wavelength accuracy
This example program uses the Keysight 86120B to increase the absolute wave-
length accuracy of Keysight 8167A, 8168B, and 8168C Tunable Laser Sources.
Essentially, the Keysight 86120B’s accuracy is transferred to the tunable laser
source. The absolute accuracy of the tunable laser source is increased from <
±
0.1
nm to <
±
0.005 nm which is the Keysight 86120B’s absolute accuracy (at 1550 nm).
In order to run this program, the tunable laser source’s firmware must support the
automatic alignment command, WAVEACT.
The program uses the following measurement algorithm:
Identify and initialize the Keysight 86120B and tunable laser source
Ask user for desired wavelength
Set wavelength of tunable laser source
Turn tunable laser source’s output on
Enter loop
Measure wavelength
Compare wavelength to desired wavelength
Realign tunable laser source’s wavelength
Check if wavelength changed from last pass
Repeat until (delta wavelength < 0.0015 nm or wavelength is stable)