Keysight Technologies 81940A User manual

Keysight 81940A, 44A, 49A,
80A & 89A Compact Tunable
Laser Source Modules
User’s Guide

Notices
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Manual Part Number
81980-90A11
Edition
Edition 5, March 2015
Edition 4, April 2005
Edition 3, January 2005
Edition 2, July 2004
Edition 1, October 2003
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In This Guide...
Chapter 1, “Getting Started.
This chapter contains an introductory description of the modules and aims
to make the modules familiar to you.
Chapter 2, “Accessories.
This chapter contains details of the various modules and options available.
Chapter 3, “Specifications.
This chapter contains the full performance specifications for the modules.
Chapter 4, “Performance Tests.
This chapter contains full detailed instructions that enable you to run a
performance test on a High Power Optical Attenuator. Also included are
Test Report sheets to record the measurements taken during the
performance test.
Chapter 5, “Cleaning Information.
This appendix contains information as to how best clean your instrument,
along with some general safety instructions that you should follow when
cleaning your instrument.

Keysight 81940A, 44A, 49A, 80A & 89A Compact TLS modules, Edition 5 5
Table of Contents
Getting Started 11
Safety Considerations 12
Safety Symbols 12
Initial Inspection 13
Line Power Requirements 13
Operating Environment 13
Input/Output Signals 14
Storage and Shipment 14
Initial Safety Information for Tunable Laser Modules 15
Laser Safety Labels 16
Introduction 17
Typical Use Models 20
Optical Output 22
Polarization Maintaining Fiber 22
Angled and Straight Contact Connectors 23
Signal Input and Output 24
Accessories 25
Modules and Options 26
Modules 27
Options 27
Connector Interfaces 28
User’s Guides 29
Specifications 31
Definition of Terms 32
General Definitions 46
Compact Tunable Laser Module Specifications 47
Conditions 53
Supplementary Performance Characteristics 54
General 56

6Keysight 81940A, 44A, 49A, 80A & 89A Compact TLS modules, Edition 5
Performance Tests 57
Required Test Equipment 58
Test Record 59
Performance Test Instructions 60
General test Setup 60
Wavelength Tests 61
Wavelength Meter Settings for all Wavelength Tests 61
Wavelength Accuracy 62
Absolute and Relative Wavelength Accuracy 62
Mode-Hop Free Tuning 66
Wavelength Repeatability 67
Power Tests 69
Maximum Output Power 69
Power Linearity 74
Power Flatness versus Wavelength 77
Power Stability 80
Signal-to-Source Spontaneous Emission Ratio 83
Optional Performance Tests 86
Signal-to-Total-Source Spontaneous Emission Ratio 86
Test Records 90
Test Record 91
Test Record 101
Test Record 111
Test Record 118
Test Record 128
Cleaning Information 139
Cleaning Instructions 140
Safety Precautions 140
Why is it important to clean optical devices ? 141
What do I need for proper cleaning? 142
Preserving Connectors 146
Cleaning Instrument Housings 146
Which Cleaning Procedure should I use? 147
How to clean connectors 148
How to clean connector interfaces 150

Keysight 81940A, 44A, 49A, 80A & 89A Compact TLS modules, Edition 5 7
How to clean bare fiber adapters 151
How to clean instruments with a fixed connector interface 152
Additional Cleaning Information 153
Other Cleaning Hints 154
Index 155

8Keysight 81940A, 44A, 49A, 80A & 89A Compact TLS modules, Edition 5