YOKOGAWA AQ6370D User manual

User’s
Manual AQ6370D
Optical Spectrum Analyzer
IM AQ6370D-01EN
5th Edition

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Please allow us to serve you best by completing the product registration form
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http://tmi.yokogawa.com/
PIM 103-04E

i
IM AQ6370D-01EN
Thank you for purchasing the AQ6370D Optical Spectrum Analyzer. This instrument
enables high speed measurement of the optical properties of LD and LED light sources,
optical amps, and other devices. To improve ease of use, it includes mouse-based user
operation and a brand-new zoom function.
This user’s manual describes the instrument’s functions, operating procedures, and
handling precautions, and provides other important information for use of the instrument.
For correct operation, please read this manual thoroughly before use. After reading this
manual, keep it in a convenient location for quick reference in the event a question arises
during operation.
List of Manuals
The following manuals, including this one, are provided as manuals for the AQ6370D.
Please read all manuals.
Manual Title Manual No. Description
AQ6370D
Optical Spectrum Analyzer
User’s Manual
IM AQ6370D-01EN The manual is located on the CD included
in your package (pdf format). Explains
all functions and operating procedures of
the AQ6370D except remote control and
program functions.
AQ6370C/AQ6370D/AQ6373/
AQ6373B/AQ6375/AQ6375B
Optical Spectrum Analyzer
Remote Control User’s Manual
IM AQ6370C-17EN The manual is located on the CD included
in your package (pdf format).Explains
functions for controlling the instrument with
communication commands and program
functions.
AQ6370D
Optical Spectrum Analyzer
Getting Started Guide
IM AQ6370D-02EN This manual. Explains the handling
precautions, installation procedure,
component names, and specifications of
the AQ6370D.
Model AQ6370D-01
AQ6370D Optical Spectrum
Analyzer Limited model
IM AQ6370D-51EN Explains the specifications of the limited
model of the AQ6370D.
The “EN” in the manual number is the language code.
Contact information of Yokogawa offices worldwide is provided on the following sheet.
Document Description Description
PIM 113-01Z2 List of worldwide contacts
Notes
• The contents of this manual are subject to change without prior notice as a result
of improvements in the instrument’s performance and functions. Display contents
illustrated in this manual may differ slightly from what actually appears on your screen.
• Every effort has been made in the preparation of this manual to ensure the accuracy
of its contents. However, should you have any questions or find any errors, please
contact your nearest YOKOGAWA dealer.
• Copying or reproducing all or any part of the contents of this manual without the
permission of YOKOGAWA is strictly prohibited.
Trademarks
• Microsoft and Windows are registered trademarks or trademarks of Microsoft
Corporation in the United States and/or other countries.
• Adobe and Acrobat are registered trademarks or trademarks of Adobe Systems
incorporated.
• In this manual, the ® and TM symbols do not accompany their respective registered
trademark or trademark names.
• Other company and product names are registered trademarks or trademarks of their
respective companies.
5th Edition: October 2017 (YMI)
All Rights Reserved, Copyright © 2014 Yokogawa Test & Measurement Corporation

ii IM AQ6370D-01EN
Revisions
• 1st Edition: April 2014
• 2nd Edition: July 2014
• 3rd Edition: July 2015
• 4th Edition: May 2017
• 5th Edition: October 2017

iii
IM AQ6370D-01EN
Conventions Used in This Manual
Safety Markings
The following markings are used in this manual.
Improper handling or use can lead to injury to the user or damage
to the instrument. This symbol appears on the instrument to indicate
that the user must refer to the userʼs manual for special instructions.
The same symbol appears in the corresponding place in the user's
manual to identify those instructions. In the manual, the symbol is
used in conjunction with the word “WARNING” or “CAUTION.”
WARNING Calls attention to actions or conditions that could cause serious or
fatal injury to the user, and precautions that can be taken to prevent
such occurrences.
CAUTION Calls attentions to actions or conditions that could cause light injury to
the user or damage to the instrument or user’s data, and precautions
that can be taken to prevent such occurrences.
Note Calls attention to information that is important for proper operation of
the instrument.
Notations Used on Pages Describing Operating Procedures
On pages that describe the operating procedures in Chapter 3 through 11, the following
notations are used to distinguish the procedures from their explanations.
Procedure This subsection contains the operating procedure used to carry out
the function described in the current chapter. The procedures are
written with inexperienced users in mind; experienced users may not
need to carry out all the steps.
Explanation This subsection describes the setup parameters and the limitations on
the procedures. It may not give a detailed explanation of the function.
For a detailed explanation of the function, see chapter 2.
Notations Used in the Procedures
Panel Keys and Soft keys
Bold characters used in the procedural explanations indicate characters that are marked on the
panel keys or the characters of the soft keys displayed on the screen menu.
Unit
k: Denotes “1000.” Example: 100 kS/s
K: Denotes “1024.” Example: 459 KB (file data size)

iv IM AQ6370D-01EN
Flow of Operation
The figure below is provided to familarize the first-time user with the general flow of this
instrument operation. For a description of each item, see the relevant section or chapter.
Preparing for Measurement
Setting Conditions and Measuring
Waveform Display
Installing the Instrument
Turning the Power ON/OFF
Wavelength Calibration
Auto Sweep Setting and Measurement
Other Settings
Measurement Start (Sweep)
External Trigger Measurement
Waveform Display
Displaying Calculated Waveforms
Displaying Power Density
Marker Display
Searching
Waveform Analysis
Waveform Analysis
GO/NO-GO Judgment
Saving Display Data and Printing Out
Storage Media
Saving Data
Section 3.1
Section 3.4
Section 3.7
Section 5.1
Sections 5.2 to 5.12
Section 5.13
Section 5.16
Sections 6.1 to 6.4
Section 6.5
Section 6.8
Section 6.9
Sections 6.13 and 6.14
Sections 7.1 to 7.9
Section 7.12
Section 8.1
Sections 8.2 to 8.10

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IM AQ6370C-01EN
: Section 3.1, 3.2, 3.4 to 3.7, 8.3 to 8.11 10.7
Contents
List of Manuals...................................................................................................................................i
Conventions Used in This Manual ................................................................................................... iii
Flow of Operation.............................................................................................................................iv
Chapter 1 Part Names and Functions
1.1 Front Panel....................................................................................................................... 1-1
1.2 Rear Panel ....................................................................................................................... 1-2
1.3 Panel Keys and Knobs ..................................................................................................... 1-3
1.4 LCD Screen...................................................................................................................... 1-6
Chapter 2 Functions
2.1 System Structure.............................................................................................................. 2-1
2.2 Measurement ................................................................................................................... 2-2
2.3 Waveform Display ........................................................................................................... 2-7
2.4 Analysis .......................................................................................................................... 2-12
2.5 Other .............................................................................................................................. 2-14
Chapter 3 Preparing for Measurement
3.1 Installing the Instrument ................................................................................................... 3-1
3.2 Attaching the Connector Adapter ..................................................................................... 3-3
3.3 Connecting the Device ..................................................................................................... 3-5
3.4 Turning the Power ON/OFF.............................................................................................. 3-7
3.5 Connecting the DUT....................................................................................................... 3-12
3.6 Alignment Adjustment..................................................................................................... 3-14
3.7 Wavelength Calibration .................................................................................................. 3-18
3.8 Resolution Calibration .................................................................................................... 3-23
3.9 Important Points During Measurement........................................................................... 3-27
Chapter 4 Common Operations
4.1 Description of Soft Keys ................................................................................................... 4-1
4.2 Using the Mouse and External Keyboard......................................................................... 4-3
4.3 Entering Numerical Values and Strings............................................................................ 4-5
4.4 Screen Display ................................................................................................................. 4-7
4.5 Setting the Date and Time................................................................................................ 4-8
Chapter 5 Measurement
5.1 Auto Measurement ........................................................................................................... 5-1
5.2 Horizontal/Vertical Axis Settings....................................................................................... 5-2
5.3 Sub Scale ......................................................................................................................... 5-7
5.4 Setting the Reference Level ............................................................................................5-11
5.5 Center Wavelength (Center Frequency) Setting ............................................................ 5-15
5.6 Sweep Width Settings .................................................................................................... 5-20
5.7 Wavelength (Frequency) Resolution Settings ................................................................ 5-24
5.8 Sampling Point/Interval Settings .................................................................................... 5-27
5.9 Sensitivity Settings ......................................................................................................... 5-29
5.10 Sweep Speed Settings ................................................................................................... 5-31
5.11 Averaging Times Setting................................................................................................. 5-32
5.12 Trace Settings ................................................................................................................ 5-33
5.13 Measurement Start (Sweep) .......................................................................................... 5-35
1
2
3
4
5
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7
8
9
10
11
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Index

vi IM AQ6370C-01EN
5.14 Specifying a Sweep Range ............................................................................................ 5-37
5.15 Pulse Light Measurement............................................................................................... 5-38
5.16 External Trigger Measurement ....................................................................................... 5-44
5.17 Trigger Output ................................................................................................................ 5-48
5.18 Smoothing ...................................................................................................................... 5-49
5.19 Analog Out ..................................................................................................................... 5-50
Chapter 6 Waveform Display
6.1 Zooming In/Out on Waveforms......................................................................................... 6-1
6.2 Wavelength Updating/Fixing............................................................................................. 6-8
6.3 MAX/MIN HOLD Display ................................................................................................ 6-10
6.4 Sweep Average ...............................................................................................................6-11
6.5 Displaying Calculated Waveforms.................................................................................. 6-13
6.6 Normalized Display ....................................................................................................... 6-19
6.7 Curve Fitting .................................................................................................................. 6-20
6.8 Power Density Trace ..................................................................................................... 6-26
6.9 Marker Display ............................................................................................................... 6-27
6.10 Displaying a Split Screen ............................................................................................... 6-43
6.11 Noise Mask..................................................................................................................... 6-45
6.12 Copying and Clearing Traces ......................................................................................... 6-47
6.13 Single Search ................................................................................................................. 6-49
6.14 Multi Search ................................................................................................................... 6-53
Chapter 7 Analysis
7.1 Spectrum Width Measurement......................................................................................... 7-1
7.2 Notch Width Measurement............................................................................................... 7-4
7.3 SMSR Measurement ........................................................................................................ 7-6
7.4 POWER Measurement..................................................................................................... 7-8
7.5 DFB-LD, FP-LD, and LED Measurement ......................................................................... 7-9
7.6 PMD Measurement ........................................................................................................ 7-10
7.7 WDM Transmission Signal Analysis ............................................................................... 7-12
7.8 Optical Amp Gain and NF Measurement........................................................................ 7-19
7.9 Optical Filter Characteristics Measurement ................................................................... 7-26
7.10 Editing the Grid Table ..................................................................................................... 7-35
7.11 Measurement of Level Fluctuations in Single-Wavelength Light (0 nm Sweeping)........ 7-39
7.12 Go/No-Go Judgment (Template) .................................................................................... 7-42
7.13 Specifying an Analysis Range ........................................................................................ 7-54
7.14 Correcting Displayed Values .......................................................................................... 7-57
7.15 Analysis Data Logging.................................................................................................... 7-60
Chapter 8 Saving/Loading Data
8.1 USB Storage Media.......................................................................................................... 8-1
8.2 Temporarily Saving and Redisplaying Traces to and from Internal Memory .................... 8-2
8.3 Saving/Loading Displayed Data ....................................................................................... 8-6
8.4 Saving/Loading Displayed Data(All Trace)..................................................................... 8-22
8.5 Saving/Loading Setting Data.......................................................................................... 8-28
8.6 Saving/Loading Analysis Results Data........................................................................... 8-33
8.7 Saving/Loading Program Data ....................................................................................... 8-40
8.8 Saving Screen Image Data ............................................................................................ 8-46
8.9 Saving/Loading Template Data....................................................................................... 8-50
8.10 Saving and Loading Logging Data ................................................................................. 8-56
8.11 Creating Files ................................................................................................................. 8-62
Contents

vii
IM AQ6370C-01EN
: Section 3.1, 3.2, 3.4 to 3.7, 8.3 to 8.11 10.7
Chapter 9 Other Operations
9.1 Registering Soft keys ....................................................................................................... 9-1
9.2 Data Initialization .............................................................................................................. 9-2
9.3 Help ................................................................................................................................ 9-16
9.4 Registering and Loading Character Strings ................................................................... 9-17
9.5 Locking Keys .................................................................................................................. 9-18
9.6 Other Settings ................................................................................................................ 9-20
9.7 Displaying System Information....................................................................................... 9-25
Chapter 10 Maintenance
10.1 Updating the Firmware ................................................................................................... 10-1
10.2 Mechanical Inspection.................................................................................................... 10-4
10.3 Operational Inspection ................................................................................................... 10-5
10.4 Inspection of Wavelength Accuracy................................................................................ 10-6
10.5 Inspection of Level Accuracy.......................................................................................... 10-7
10.6 Replacing Fuses............................................................................................................. 10-8
10.7 Daily Maintenance.......................................................................................................... 10-9
10.8 Care during Storage ......................................................................................................10-11
10.9 Recommended Replacement Parts ............................................................................. 10-12
10.10 Warning Display Function............................................................................................. 10-13
Chapter 11 Specications
11.1 Specications ..................................................................................................................11-1
11.2 External Dimensions .......................................................................................................11-4
Appendix
Appendix 1 GRID Table for WDM Wevelength.......................................................................App-1
Appendix 2 Data Calculation Algorithms for Spectrum Widths...............................................App-2
Appendix 3 Details of Each Analytical Functions ................................................................. App-11
Appendix 4 Detailed Explanations of WDM Analysis Function.............................................App-19
Appendix 5 Details of Optical Amplifier Analysis Function ................................................... App-30
Appendix 6 Details of Optical Filter Analysis Function .........................................................App-33
Appendix 7 Soft Key Tree Diagram......................................................................................App-50
Appendix 8 END USER LICENSE AGREEMENT................................................................App-69
Index
Contents
1
2
3
4
5
6
7
8
9
10
11
App
Index

1-1
IM AQ6370D-01EN
1
2
3
4
5
6
7
8
9
10
11
App
Index
Part Names and Functions
1.1 Front Panel
Front Panel
AQ6370D
OPTICAL SPECTRUM ANALYZER
USB
POWER
FUNCTION DATA ENTRY
CENTER
SWEEP
SPAN LEVEL
ZOOM
SETUP
MARKER
DISPLAY
PEAK
SEARCH
TRACE
ANALYSIS
USER MEMORY FILE
SYSTEM
ADVANCE
PROGRAM
OREMOTE
UNDO/
LOCAL
HELP
COARSE
7 8 9
4 5 6
1 2 3
0 .
-
BACK
SPASE
nm/
ENTER
m/
ENTER
OPTICAL INPUT
(600 1700nm)
CALIBRATION
OUTPUT
1 2
3 4
5 6 7 8
9 10
COPY
PRESET
11 12
No. Name Function
1 LCD display Displays measured waveform, measurement conditions,
measurement values, etc.
2 Soft key section Used to execute the functions assigned to the soft keys on
the right side of the LCD display
3 FUNCTION section Used to enter settings pertaining to all measurements
(sweep, measurement conditions, data analysis, and
various functions)
4 DATA ENTRY section Used for measurement condition parameter input, label
input, etc.
5 POWER Used to start and shut down the instrument.
6 USB interface Used to connect USB storage media
7 UNDO/LOCAL See the following table(1.3 Panel keys and Knobs)
8 HELP Used to check the contents of the soft key menu displayed
on the screen.
9 OPTICAL INPUT Optical input connector
10 CALIBRATION OUTPUT Reference light source optical output connector used for
alignment adjustments and wavelength calibration (when
the built-in light source specification is -L1)
11 COPY Save the screen as an image file.
12 PRESET Clears all internal settings of the AQ6370D except for the
remote interface (ETHERNET, GP-IB, and RS232) settings.
Chapter 1 Part Names and Functions

1-2 IM AQ6370D-01EN
1.2 Rear Panel
Rear Panel
1
2 3 4
5
6
7 8 9
10
11
AQ6370D-02, A6370D-12, A6370D-22
7 8 9
10
11
23 4
1
56
AQ6370D-01, A6370D-10, A6370D-20
No. Name Function
1 GP-IB GP-IB port for controlling this unit through an external
computer
2 TRIGGER IN Input connector for synchronous signals for the
synchronous measurement function with the Tunable Laser
Source
3 TRIGGER OUT Output connector for synchronous signals for the
synchronous measurement function with the Tunable Laser
Source
4 ANALOG OUT Analog output
5 MAIN POWER Used to turn the main power ON/OFF
6 Power cord connector Connect the power cord to this connector
7 VIDEO OUT (SVGA) Analog RGB video signal (SVGA-compliant) interface
8 SERIAL RS-232 interface
9 ETHERNET Ethernet Interface (10/100BASE-TX)
10 USB interface Used to connect USB storage media or USB mouse
11 Exhaust holes

1-3
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7
8
9
10
11
App
Index
Part Names and Functions
1.3 Panel Keys and Knobs
FUNCTION Section
The FUNCTION section contains 17 function keys and 4 auxiliary keys. When you press
a function key, information about the function is displayed on the soft key menu located
on the right side of the LCD display.
SWEEP
The SWEEP key contains functions related to sweeping. When you press the SWEEP
key, the soft key menu for sweeping appears.
CENTER
The CENTER key contains functions related to setting the center wavelength and center
frequency for measurements. The soft key functions change depending on whether the
screen display mode is wavelength display mode or frequency display mode.
SPAN
The SPAN key contains functions pertaining to settings for the wavelength span or
frequency span being measured. The soft key functions change according to whether the
screen display mode is wavelength display mode or frequency display mode.
LEVEL
The LEVEL key contains functions related to level axis settings.When you press the
LEVEL key, the soft key menu for setting reference level appears.
SETUP
The SETUP key contains functions related to measurement condition settings.
ZOOM
The ZOOM key contains the zoom function, which allows the user to freely enlarge or
reduce a measured waveform in order to check a small area of the measured waveform,
or to check the overall waveform.
This key is used to set the waveform enlarged/reduced display conditions.
DISPLAY
The DISPLAY key contains functions related to screen display.This key is used to set the
screen to upper/lower 2-split display mode (split mode).
TRACE
The TRACE key contains functions related to trace mode settings.
MARKER
The MARKER key contains functions related to markers.
PEAK SEARCH
The PEAK SEARCH key contains functions for searching for peaks and bottoms in
measured waveforms.
ANALYSIS
The ANALYSIS key contains functions related to measured waveform analysis.
FUNCTION
CENTER
SWEEP
SPAN LEVEL
ZOOM
SETUP
MARKER
DISPLAY
PEAK
SEARCH
TRACE
ANALYSIS
USER MEMORY FILE
SYSTEM
ADVANCE
PROGRAM
OREMOTE
UNDO/
LOCAL
HELP
COPY
PRESET

1-4 IM AQ6370D-01EN
MEMORY
The MEMORY key contains functions for writing the contents of the active trace to the
unit’s internal memory. When you press the MEMORY key, the traces and memory list
screen (soft key menu) are displayed. A memory number may be entered in the DATA
ENTRY section, or selected using the rotary knob or arrow keys.
FILE
The FILE key contains functions for saving and loading waveform data, program data,
and the like to and from USB storage media (USB memory/HDD).
PROGRAM
The PROGRAM key contains the soft keys related to program functions for controlling
measurements through a program.
SYSTEM
The SYSTEM key contains system-related functions such as monochromator adjusting
optical alignment, wavelength adjustment, hardware setup, and setting initialization.
ADVANCE
The ADVANCE key contains functions for setting reference data used to make
comparison judgments on measured data and for logging analysis data.
USER
Frequently used soft keys can be registered on the soft key menu in the USER key.
Registering frequently used soft keys in the USER key allows you to execute frequently
used functions in a small number of steps.
COPY
The COPY key is used to output the measurement screen to the internal printer or a file.
When you press the COPY key, the measured waveforms and lists displayed on the
screen are output to the internal printer or a file.
PRESET
The PRESET key clears all internal settings of the AQ6370D except for the remote
interface (ETHERNET, GP-IB, and RS232) settings.
UNDO/LOCAL
The key’s function changes depending on the status of the instrument when the UNDO/
LOCAL key is pressed. The following table shows the key’s functions.
Status of Instrument Function
UNDO action is allowed If the UNDO key is pressed after changing parameter settings,
changing or deleting data, etc., the previous action (change,
deletion, etc.) is canceled and the state preceding that action
is restored.
During user key registration If the UNDO key is pressed during user key registration,
registration mode is canceled and the soft key menu which
appeared when the SYSTEM key was pressed is displayed
again.
During remote control by external
PC (Remote light is on)
Changes the state from the remote state back to the local
state. The remote light turns off.
HELP
When you press the HELP key, a soft key menu of the currently displayed screen is
displayed explanations.
Soft keys for selecting the “MORE INFO” which indicate additional information are
displayed by some soft keys in HELP screen.
1.3 Panel keys and Knobs

1-5
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1
2
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8
9
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11
App
Index
Part Names and Functions
DATA ENTRY Section
This unit allows you to enter measurement conditions and various other parameters
through the DATA ENTRY section. Three different entry methods can be used in the
DATA ENTRY section, the rotary knob, the arrow keys, and the numeric keypad.
Rotary knob
When you press a soft key which has a parameter, the current setting is displayed in
the parameter entry window. Turning the rotary knob raises or lowers the numeric value
shown in the parameter entry window (turn clockwise to increase and counterclockwise
to decrease), and the internal setting changes at the same time.
Note that if the COARSE key is on (lamp on), the numeric value increase/decrease step
will be larger.
Arrow keys (▲, ▼)
Pressing the ▲ key has the same effect as turning the rotary knob clockwise. Likewise,
pressing the ▼ key has the same effect as turning the rotary knob counterclockwise.
Holding an arrow key down for 0.5 second or longer activates auto-repeat.
If the multi-marker function has been selected, the arrow keys can be used to scroll the
marker value display in the data area.
COARSE Key
You can raise the digit of settings being entered or the increase/decrease step for
numerical values.
Each time you press this key the setting toggles between ON and OFF. When ON, the
lamp lights.
Numeric keypad
You can enter numerical values directly into the parameter input window by pressing
keys of the numeric keypad.
After you have pressed a parameter soft key to display the current setting in the
parameter display area, you can press a numeric keypad key to display the numeric
keypad input area including the entered numeric value.
If the value entered with the numeric keypad is not in the allowed value range, the
nearest allowed value will be set.
μm/ENTER Key and nm/ENTER Key
Enters values input using the numeric keypad or the parameter input window.
Use one or the other key if entering a parameter value with a particular unit.
If a parameter does not have a unit associated with it, you can use either the μm/ENTER
key or the nm/ENTER key.
BACK SPACE Key
Use this key if you make an error when inputting values with the numeric keypad. The
last entered (right-most) character is removed, allowing entry of the correct character.
By holding the BACK SPACE key down, you can erase the entire entry in the numeric
keypad input area and make the numeric keypad input area disappear, returning it to the
condition preceding numeric keypad input.
1.3 Panel keys and Knobs
DATA ENTRY
COARSE
7 8 9
4 5 6
1 2 3
0 .
-
BACK
SPASE
nm/
ENTER
m/
ENTER

1-6 IM AQ6370D-01EN
1.4 LCD Screen
1
2
3
4
5
6
7 8 9 10 11 12 13
14 15 16 17
18
19
20
21
22
23
No. Function
1 Data area
2 Measurement conditions area
3(Displayed when any of the measurement conditions are changed.)
4 Displays level axis scale per DIV
5(Displayed when measurement is not correctly carried out.)
6 Displays reference level
7 Label area (56 characters)
8 Displays wavelength resolution
9 Displays measurement sensitivity
10 Displays averaging times
11 Displays the number of measurement samples
12 Displays date and time
13 Displays each trace status
14 (Only displayed when ZOOM function is used)
15 Displays the statuses of main settings
(When a setting is ON, its display is depressed, or is displayed with white on black
background if the display colors are black and white.)
16 Displays wavelength axis scale per DIV
17 Displays sweep status
(RPT=Repeat; SGL=Single; STP=Stop)

1-7
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8
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App
Index
Part Names and Functions
No. Function
18 Displays soft key menu
(Displays markers and data analysis results.)
19 Parameter display area
20 Parameter input area
21 OVERVIEW display screen
(Only displayed when ZOOM function is used.)
22 Displays sub-scale
23 This appears when a resolution calibration has been performed.
1.4 LCD Screen

2-1
IM AQ6370D-01EN
Functions
1
2
3
4
5
6
7
8
9
10
11
App
Index
Chapter 2 Functions
2.1 System Structure
System Structure
AQ6370
OPTICALSPECTRUM ANALYZER
USB
POWER
FUNCTION DATA ENTRY
CENTER
SWEEP
SPAN LEVEL
ZOOM
SETUP
MARKER
DISPLAY
PEAK
SEARCH
TRACE
ANALYSIS
USER MEMORY FILE
SYSTEM
ADVANCE
PROGRAM
OREMOTE
UNDO/
LOCAL
HELP
COPY
FEED
COARSE
7 8 9
4 5 6
1 2 3
0 .
-
BACK
SPASE
nm/
ENTER
m/
ENTER
OPTICAL INPUT
(600 1700nm)
CALIBRATION
OUTPUT
Control target
GP-IB interface
RS-232 interface
Ethernet interface
USB mouse
USB storage
medium
PC
Analog output
External trigger input
Video signal output
trigger output
USB mouse
USB keyboard
USB storage
medium
USB 101 keyboard

2-2 IM AQ6370D-01EN
2.2 Measurement
Alignment Adjustment <<See section 3.6 for the operating procedure>>
This function allows adjustment of the optical axis of the instrument’s built-in
monochromator (spectroscope).
The instrument’s optical performance is not guaranteed until the alignment adjustment
function has been executed. Failure to perform this adjustment can result in distortion
of measured waveforms. After alignment adjustment has been executed, wavelength
calibration is also subsequently performed automatically. If you are using the instrument
for the first time or using it after it has been severely shaken while being moved, perform
the alignment adjustment procedure after warm-up ends.
Wavelength Calibration <<See section 3.7 for the operating procedure>>
Wavelength calibration can be performed using the internal reference light source (when
the built-in light source specification is -L1) or an external light source.
Resolution Calibration <<See section 3.8 for the operating procedure>>
Typically the filter response of an optical spectrum analyzer is not rectangular, and
thus the resolution bandwidth differs slightly from the equivalent noise bandwidth. This
difference becomes prominent especially when the wavelength resolution is high (e.g.,
0.05 nm or less). The resolution calibration function measures the equivalent noise
bandwidth at each resolution setting and internally sets the resolution bandwidth to the
result. The resolution bandwidth appears in parentheses in each of the resolution soft
keys on the resolution screen. The resolution bandwidth accuracy affects the results of
noise measurements and the results of optical power measurements of wideband light
sources. In detail, the resolution bandwidth is used when the following analysis and
computation functions are executed. For details, see pages 3-25 and 3-26.
• WDM analysis
• EDFA-NF (optical amp gain, NF measurement)
• Power analysis
• OSNR and total power of DFB-LD analysis
• Total power of FP-LD analysis
• Total power of LED analysis
• Power density markers, Integrated power markers
Auto Measurement <<See section 5.1 for the operating procedure>>
This function automatically sets the optimal measuring conditions for the input light and
displays the spectrum waveform. This function is useful when the characteristics of the
input light are not well known.
The wavelength range of input light that can be auto-measured is 1200–1670 nm.
The measurement conditions that are set automatically are as follows.
1. Span (SPAN)
2. Center wavelength (CENTER)
3. Reference level (REF LEVEL)
4. Resolution (RESOLUTION)
Other measuring conditions (sensitivity, averaging times, number of sampling points,
and interval settings) are set to their defaults. The horizontal and vertical axes of the
displayed spectrum waveform are zoomed to an appropriate degree.
Single Sweep <<See section 5.13 for the operating procedure>>
This function executes a single sweep or forcibly stops a sweep operation.

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IM AQ6370D-01EN
Functions
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Index
Repeat Sweep <<See section 5.13 for the operating procedure>>
This function performs repeat sweeping or forcibly stops a sweep operation. It enables
repeated, real-time measurement of waveforms.
Sweeping between Markers << See section 5.14 for the operating procedure >>
This function enables sweeping between two specified waveform line markers. You can
sweep any desired area on screen.
Segment Measurement <<See section 5.13 for the operating procedure>>
This function allows you to divide up items to be measured in units of previously specified
segments.
Allows measurement delimited by segments (portions).
Smoothing << See section 5.18 for the operating procedure >>
This function attenuates the noise in the measured waveform. By using the Smoothing
function, areas on the waveform with a large amount of noise can be “smoothed out”
when measured.
One-Action Keys <<See sections 5.4 to 5.6 for the operating procedure>>
This is the general name for a key that uses data from the active trace waveform (the
currently displayed waveform) to set measurement conditions.
Setting conditions requires that a waveform is displayed for the active trace.
One-Action Key Name Description
PEAK → REF LEVEL Sets the peak level of the measured waveform of the active trace as
the reference level.
MARKER→ REF LEVEL Sets the moving marker level as the reference level.
PEAK→CENTER Sets the peak wavelength or the peak frequency of the active trace
measurement waveform to center wavelength or center frequency.
MEAN WL→CENTER Sets THRESH 3 dB center wavelength or center frequency of the
active trace measured waveform to center wavelength or center
frequency.
VIEW→MEAS Sets the currently displayed ZOOM scale as the measurement scale
(CENTER, START, STOP, SPAN) for the next sweep.
MARKER →CENTER Sets the wavelength of the moving marker to center wavelength or
center frequency.
Δλ→SPAN Sets the sweep width as six times the RMS 20 dB width of the
active trace measurement waveform.
MKR L1-L2 →SPAN Sets spacing between line markers 1 and 2 for sweep width.
PEAK→ZOOM CTR Sets the peak wavelength of the active trace measurement
waveform to center wavelength or center frequency of zoom display.
MARKER →ZOOM CTR Sets the wavelength of the moving marker to center wavelength or
center frequency of zoom display.
MKR L1-L2 →ZOOM SPAN Sets spacing between line markers 1 and 2 for sweep width of zoom
display.
2.2 Measurement

2-4 IM AQ6370D-01EN
Switching between Vacuum Wavelength and Air Wavelength
<<See section 5.2 for the operating procedure>>
This function switches the measured wavelength to either a vacuum wavelength or an air
wavelength.
Measurement can be performed in either air or vacuum wavelength mode.
Switching between Wavelength and Frequency
<<See section 5.2 for the operating procedure>>
This function switches the horizontal axis display to wavelength or frequency.
You can display either the wavelengths or frequencies of marker values and analysis
results.
Averaging <<See section 5.11 for the operating procedure>>
This function performs multiple measurements and displays the average values.
The function is used in cases such as: when the light source’s level is fluctuating; when
measuring a modulated signal of several kHz or less; when the waveform is disrupted
and difficult to measure; when it is necessary to obtain even higher measurement
sensitivity.
Power Density Display <<See section 7.4 for the operating procedure>>
The power per 1 nm is called the power density.
The level axis of the AQ6370D indicates the absolute power per wavelength resolution.
For example, if the resolution is set to 0.1 nm, the power per 0.1 nm will be displayed.
Since the optical spectrum of such devices as a gas laser or a laser diode is narrower
than the wavelength resolution of the instrument, the entire power is accommodated
within the band of a resolution. Therefore, the measured power (peak level) is equal
to the total power of the light source. This instrument has been calibrated to display
accurate power under such conditions.
On the other hand, natural light or lights such as fluorescent lamps or LEDs, have,
in many cases, optical spectrums wider than the wavelength resolution set for the
instrument. Therefore, if the instrument measures these lights, measured power will vary,
depending on the resolution setting.
In order to deal with this issue, the instrument is equipped with the dBm dBm/nm soft key
to allow the level axis displays to switch from the absolute power (dBm, mW, μW, nW,
pW) per resolution to power density (dBm/nm, mW/nm, μW/nm, nW/nm, pW/nm).
In the case of power density displays, a measured value is converted to power per 1 nm.
Therefore, whatever resolution is used for measurement, certain measured values will
always be available.
For information on the use of dBm and dBm/nm, see “Power Density Display” in section
5.2, “Horizontal/Vertical Axis Settings.”
The trace computation function can be used to display the power density in the specified
bandwidth within the range of 0.1 nm to 10 nm (see section 6.8).
Note
Specifications such as level accuracy, measurement level range, and level linearity of the
instrument are provided for the absolute power display.
2.2 Measurement