Agilent 83437A
Broadband Light Source
User’s Guide
© Copyright 2000
Agilent Technologies
All Rights Reserved. Reproduction, adaptation, or translation without prior written
permission is prohibited,
except as allowed under copyright laws.
Agilent Part No. 83437-90010
Printed in USA
February 2000
Agilent Technologies
Lightwave Division
1400 Fountaingrove Parkway
Santa Rosa, CA 95403-1799,
USA
(707) 577-1400
Notice.
The information contained in
this document is subject to
change without notice. Companies, names, and data used
in examples herein are fictitious unless otherwise noted.
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regard to this material, including but not limited to, the
implied warranties of merchantability and fitness for a
particular purpose. Agilent
Technologies shall not be liable for errors contained herein
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performance, or use of this
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Data and Computer Software
clause at DFARS 252.227-7013
for DOD agencies, and subparagraphs (c) (1) and (c) (2)
of the Commercial Computer
Software Restricted Rights
clause at FAR 52.227-19 for
other agencies.
Warranty.
This Agilent Technologies
instrument product is warranted against defects in
material and workmanship for
a period of one year from date
of shipment. During the warranty period, Agilent Technologies will, at its option, either
repair or replace products
which prove to be defective.
For warranty service or repair,
this product must be returned
to a service facility designated by Agilent Technologies. Buyer shall prepay
shipping charges to Agilent
Technologies and Agilent
Technologies shall pay shipping charges to return the
product to Buyer. However,
Buyer shall pay all shipping
charges, duties, and taxes for
products returned to Agilent
Technologies from another
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Agilent Technologies warrants that its software and
firmware designated by Agilent Technologies for use with
an instrument will execute its
programming instructions
when properly installed on
that instrument. Agilent Technologies does not warrant that
the operation of the instrument, or software, or firmware
will be uninterrupted or errorfree.
Limitation of Warranty.
The foregoing warranty shall
not apply to defects resulting
from improper or inadequate
maintenance by Buyer, Buyersupplied software or interfacing, unauthorized modification or misuse, operation
outside of the environmental
specifications for the product,
or improper site preparation
or maintenance.
No other warranty is
expressed or implied. Agilent
Technologies specifically disclaims the implied warranties
of merchantability and fitness
for a particular purpose.
Exclusive Remedies.
The remedies provided herein
are buyer's sole and exclusive
remedies. Agilent Technolo-
gies shall not be liable for any
direct, indirect, special, incidental, or consequential damages, whether based on
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legal theory.
Safety Symbols.
CAUTION
The
caution
sign denotes a
hazard. It calls attention to a
procedure which, if not correctly performed or adhered
to, could result in damage to
or destruction of the product.
Do not proceed beyond a caution sign until the indicated
conditions are fully understood and met.
WAR NING
The
warning
sign denotes a
hazard. It calls attention to a
procedure which, if not correctly performed or adhered
to, could result in injury or
loss of life. Do not proceed
beyond a warning sign until
the indicated conditions are
fully understood and met.
The instruction manual symbol. The product is marked with this
warning symbol when
it is necessary for the
user to refer to the
instructions in the
manual.
The laser radiation
symbol. This warning
symbol is marked on
products which have a
laser output.
The AC symbol is used
to indicate the
required nature of the
line module input
power.
The ON symbols are
|
used to mark the positions of the instrument
power line switch.
The OFF symbols
❍
are used to mark the
positions of the instrument power line
switch.
The CE mark is a registered trademark of
the European Community.
The CSA mark is a registered trademark of
the Canadian Standards Association.
The C-Tick mark is a
registered trademark
of the Australian Spectrum Management
Agency.
This text denotes the
ISM1-A
instrument is an
Industrial Scientific
and Medical Group 1
Class A product.
Typographical Conventions.
The following conventions are
used in this book:
Key type
for keys or text
located on the keyboard or
instrument.
Softkey type
for key names that
are displayed on the instrument’s screen.
Display type
for words or
characters displayed on the
computer’s screen or instrument’s display.
User type
for words or charac-
ters that you type or enter.
Emphasis
type for words or
characters that emphasize
some point or that are used as
place holders for text that you
type.
ii
The Agilent 83437A—At a Glance
The Agilent 83437A—At a Glance
The Agilent 83437A Broadband Light Source provides incoherent light for
characterizing fiber-optic components. Because its single-mode output originates from edge emitting LEDs (EELEDs), the power density of the output
spectrum is considerably greater than that of surface emitting LEDs or whitelight tungsten lamp sources.
Several output wavelengths are available
Although the standard Agilent 83437A’s output is 1500 nm, your instrument
may include additional options which provide a maximum light spread of over
500 nm. Up to four internal EELED sources can be installed when selected
from the following options:
• Option 002: 1200 nm source
• Option 003: 1310 nm source
• Option 004: 1430 nm source
• Option 005: 1500 nm source deleted
• Option 006: 1650 nm source
Even if your instrument has several wavelength options, all the light is coupled
so that it emerges from one output connector.
Each EELED can be modulated or turned off
You can digitally modulate the output of each individual source using a TTL
compatible signal. For a complete discussion of modulating the output light
and making measurements with your Agilent 83437A, refer to Chapter 2,
“Making Measurements”.
iii
The Agilent 83437A—At a Glance
Measurement accuracy—it’s up to you!
Fiber-optic connectors are easily damaged when connected to dirty or damaged cables
and accessories. The Agilent 83437A’s front-panel OPTICAL OUT connector is no exception. When you use improper cleaning and handling techniques, you risk expensive
instrument repairs, damaged cables, and compromised measurements.
Before you connect any fiber-optic cable to the Agilent 83437A, refer to “Cleaning Con-
nections for Accurate Measurements” on page 2-11.
Laser classification
The Agilent 83437A is classified as an IEC LED Class 1 product. The total power of light
energy radiated out of the OPTICAL OUT connector is less than –5 dBm. Operator maintenance or precautions are not necessary to maintain safety. No controls, adjustments,
or performance of procedures result in hazardous radiation exposure.
iv
The Agilent 83437A—At a Glance
Rear view of instrument
v
General Safety Considerations
General Safety Considerations
This product has been designed and tested in accordance with IEC Publication 61010-1, Safety Requirements for Electrical Equipment for Measurement,
Control and Laboratory Use, and has been supplied in a safe condition. The
instruction documentation contains information and warnings that must be
followed by the user to ensure safe operation and to maintain the product in a
safe condition.
WARNING
WARNING
WARNING
WARNING
WARNING
If this instrument is not used as specified, the protection provided by
the equipment could be impaired. This instrument must be used in a
normal condition (in which all means for protection are intact) only.
To prevent electrical shock, disconnect the Agilent 83437A from
mains before cleaning. Use a dry cloth or one slightly dampened with
water to clean the external case parts. Do not attempt to clean
internally.
This is a Safety Class 1 product (provided with a protective earthing
ground incorporated in the power cord). The mains plug shall only be
inserted in a socket outlet provided with a protective earth contact.
Any interruption of the protective conductor inside or outside of the
product is likely to make the product dangerous. Intentional
interruption is prohibited.
No operator serviceable parts inside. Refer servicing to qualified
personnel. To prevent electrical shock, do not remove covers.
For continued protection against fire hazard, replace line fuse only
with same type and ratings, (type T 0.315A/250V for 100/120V
operation and 0.16A/250V for 220/240V operation). The use of other
fuses or materials is prohibited. Verify that the value of the linevoltage fuse is correct.
• For 100/120V operation, use an IEC 127 5×20 mm, 0.315 A, 250 V, Agilent
part number 2110-0449.
• For 220/240V operation, use an IEC 127 5×20 mm, 0.16 A, 250 V, Agilent
Technologies part number 2110-0448.
vi
General Safety Considerations
CAUTION
CAUTION
CAUTION
CAUTION
CAUTION
CAUTION
Before switching on this instrument, make sure that the line voltage selector
switch is set to the line voltage of the power supply and the correct fuse is
installed. Assure the supply voltage is in the specified range.
This product is designed for use in Installation Category II and Pollution
Degree 2 per IEC 1010 and 664 respectively.
VENTILATION REQUIREMENTS: When installing the product in a cabinet, the
convection into and out of the product must not be restricted. The ambient
temperature (outside the cabinet) must be less than the maximum operating
temperature of the product by 4°C for every 100 watts dissipated in the
cabinet. If the total power dissipated in the cabinet is greater than 800 watts,
then forced convection must be used.
Always use the three-prong ac power cord supplied with this instrument.
Failure to ensure adequate earth grounding by not using this cord may cause
instrument damage.
Do not
connect ac power until you have verified the line voltage is correct as
described in “Line Power Requirements” on page 1-7. Damage to the
equipment could result.
This instrument has autoranging line voltage input. Be sure the supply voltage
is within the specified range.
vii
Contents
The Agilent 83437A—At a Glance iii
1 Getting Started
Step 1. Inspect the Shipment 1-4
Step 2. Check the Fuse 1-6
Step 3. Connect the Line-Power Cable 1-7
Step 4. Turn on the Agilent 83437A 1-9
Returning the Instrument for Service 1-10
2 Making Measurements
Modulating the Output Light 2-3
Performing Stimulus-Response Measurements 2-4
Ambient Light Suppression 2-8
Cleaning Connections for Accurate Measurements 2-11
3 Specifications and Regulatory Information
Specifications 3-3
Regulatory Information 3-8
4 Reference
Instrument Options 4-2
Accessories 4-2
Front-Panel Fiber-Optic Adapters 4-3
Power Cords 4-4
Agilent Technologies Service Offices 4-5
5Servicing
General Information 5-4
Electrostatic Discharge Information 5-10
Troubleshooting 5-12
Performance Tests 5-18
Adjustment Procedures 5-22
Replacing Instrument Assemblies 5-27
Replaceable Parts 5-34
Replaceable Parts 5-47
Contents-1
1
Step 1. Inspect the Shipment 1-4
Step 2. Check the Fuse 1-6
Step 3. Connect the Line-Power Cable 1-7
Step 4. Turn on the Agilent 83437A 1-9
Returning the Instrument for Service 1-10
Getting Started
Getting Started
Getting Started
Getting Started
The instructions in this chapter show you how to install your Agilent 83437A.
You should be able to finish these procedures in about ten to twenty minutes.
After you’ve completed this chapter, continue with Chapter 2, “Making Mea-
surements”.
Refer to Chapter 3, “Specifications and Regulatory Information” for information on operating conditions such as temperature.
If you should ever need to clean the cabinet, use a damp cloth only.
WARNING
CAUTION
CAUTION
CAUTION
This is a Safety Class I product (provided with a protective earthing
ground incorporated in the power cord). The mains plug shall only be
inserted in a socket outlet provided with a protective earth contact.
Any interruption of the protective conductor inside or outside of the
product is likely to make the product dangerous. Intentional
interruption is prohibited.
This product has autoranging line voltage input. Be sure the supply voltage is
within the specified range.
VENTILATION REQUIREMENTS: When installing the product in a cabinet, the
convection into and out of the product must not be restricted. The ambient
temperature (outside the cabinet) must be less than the maximum operating
temperature of the product by 4°C for every 100 watts dissipated in the
cabinet. If the total power dissipated in the cabinet is greater than 800 watts,
then forced convection must be used.
This product is designed for use in INSTALLATION CATEGORY II and
POLLUTION DEGREE 2, per IEC 1010 and 664 respectively.
1-2
Getting Started
Getting Started
Measurement accuracy—it’s up to you!
Fiber-optic connectors are easily damaged when connected to dirty or damaged cables
and accessories. The Agilent 83437A’s front-panel OPTICAL OUT connector is no excep-
tion. When you use improper cleaning and handling techniques, you risk expensive
instrument repairs, damaged cables, and compromised measurements.
Before you connect any fiber-optic cable to the Agilent 83437A, “Cleaning Connections
for Accurate Measurements” on page 2-11.
1-3
Getting Started
Step 1. Inspect the Shipment
Step 1. Inspect the Shipment
1
Verify that all components ordered have arrived by comparing the shipping
forms to the original purchase order. Inspect all shipping containers.
If your shipment is damaged or incomplete, save the packing materials and
notify both the shipping carrier and the nearest Agilent Technologies service
office. Agilent Technologies will arrange for repair or replacement of
damaged or incomplete shipments without waiting for a settlement from the
transportation company. Notify the Agilent Technologies customer engineer
of any problems.
2
Make sure that the serial number and options listed on the instrument’s rearpanel label match the serial number and options listed on the shipping
document. The following figure is an example of the rear-panel serial number
label:
1-4
Step 1. Inspect the Shipment
Table 1-1. Agilent 83437A Options
Option Description
001 1550 nm isolator (offered only with standard instrument or Option 022)
002 1200 nm EELED source installed
003 1310 nm EELED source installed
004 1430 nm EELED source installed
005 Delete 1550 nm EELED source
006 1650 nm EELED source installed
011 Diamond HMS-10 fiber-optic input connector interface
013 DIN 47256 fiber-optic input connector interface
014 ST fiber-optic input connector interface
017 SC fiber-optic input connector interface
Getting Started
022 Angled contact fiber-optic output interface. Angled contact connects only with
FC/PC and Diamond HMS-10.
1-5
Getting Started
Step 2. Check the Fuse
Step 2. Check the Fuse
1
Locate the line-input connector on the instrument’s rear panel.
2
Disconnect the line-power cable if it is connected.
3
Use a small flat-blade screwdriver to open the pull-out fuse drawer.
WARNING
4
Verify that the value of the line-voltage fuse in the pull-out drawer is correct.
The recommended fuse is an IEC 127 5×20 mm, 6.3A, 250 V, Agilent part
number 2110-0703.
Notice that an extra fuse is provided in a drawer located on the fuse holder.
For continued protection against fire hazard, replace line fuse only
with same type and ratings, (type T 6.3A/250V for 100/240V
operation). The use of other fuses or materials is prohibited.
1-6
Step 3. Connect the Line-Power Cable
Step 3. Connect the Line-Power Cable
Getting Started
CAUTION
CAUTION
CAUTION
Always use the three-prong AC power cord supplied with this instrument.
Failure to ensure adequate earth grounding by not using this cord may cause
instrument damage.
Do not
connect ac power until you have verified the line voltage is correct as
described in the following paragraphs. Damage to the equipment could result.
This instrument has autoranging line voltage input. Be sure the supply voltage
is within the specified range.
1
Verify that the line power meets the requirements shown in the following table.
Line Power Requirements
Power: 115 VAC: 50 WATTS MAX.
230 VAC: 50 WATTS MAX.
Voltage nominal: 115 VAC / 230 VAC
range 115 VAC: 90-132 V
range 230 VAC: 198-254 V
Frequency nominals: 50 Hz / 60 Hz
range: 47-63 Hz
2
Connect the line-power cord to the instrument’s rear-panel connector.
1-7
Getting Started
Step 3. Connect the Line-Power Cable
3
Connect the other end of the line-power cord to the power receptacle.
Various power cables are available to connect the Agilent 83437A to ac power
outlets unique to specific geographic areas. The cable appropriate for the area
to which the Agilent 83437A is originally shipped is included with the unit. You
can order additional ac power cables for use in different geographic areas.
Refer to “Power Cords” on page 4-4.
1-8
Step 4. Turn on the Agilent 83437A
Step 4. Turn on the Agilent 83437A
Getting Started
1
Press the front-panel
The front-panel
ply after the EMC filters and before other parts of the instrument.
2
Use the front-panel
If the Agilent 83437A fails to turn on properly, consider the following possibilities:
• Is the line fuse good?
• Does the line socket have power?
• Is it plugged into the proper ac power source?
If the instrument still fails, return it to Agilent Technologies for repair. Refer to
“Returning the Instrument for Service” on page 1-10.
LINE
key.
LINE
switch disconnects the mains circuits from the mains sup-
ACTIVE
key to turn the light output on and off.
1-9
Getting Started
Returning the Instrument for Service
Returning the Instrument for Service
The instructions in this section show you how to properly return the instrument for repair or calibration. Always call the Agilent Technologies Instrument
Support Center first to initiate service
service office. This ensures that the repair (or calibration) can be properly
tracked and that your instrument will be returned to you as quickly as possible. Call this number regardless of where you are located. Refer to “Agilent
Technologies Service Offices” on page 4-5 for a list of service offices.
Agilent Technologies Instrument Support Center . . . . . . . . . . . (800) 403-0801
If the instrument is still under warranty or is covered by an Agilent Technologies maintenance contract, it will be repaired under the terms of the warranty
or contract (the warranty is at the front of this manual). If the instrument is
no longer under warranty or is not covered by an Agilent Technologies maintenance plan, Agilent Technologies will notify you of the cost of the repair after
examining the unit.
When an instrument is returned to a Agilent Technologies service office for
servicing, it must be adequately packaged and have a complete description of
the failure symptoms attached. When describing the failure, please be as specific as possible about the nature of the problem. Include copies of additional
failure information (such as the instrument failure settings, data related to
instrument failure, and error messages) along with the instrument being
returned.
before
returning your instrument to a
Preparing the instrument for shipping
1
Write a complete description of the failure and attach it to the instrument.
Include any specific performance details related to the problem. The following
1-10
Getting Started
Returning the Instrument for Service
information should be returned with the instrument.
• Type of service required.
• Date instrument was returned for repair.
• Description of the problem:
• Whether problem is constant or intermittent.
• Whether instrument is temperature-sensitive.
• Whether instrument is vibration-sensitive.
• Instrument settings required to reproduce the problem.
• Performance data.
• Company name and return address.
• Name and phone number of technical contact person.
• Model number of returned instrument.
• Full serial number of returned instrument.
• List of any accessories returned with instrument.
2
Cover all front or rear-panel connectors that were originally covered when you
first received the instrument.
CAUTION
CAUTION
Cover electrical connectors to protect sensitive components from electrostatic
damage. Cover optical connectors to protect them from damage due to physical
contact or dust.
Instrument damage can result from using packaging materials other than the
original materials. Never use styrene pellets as packaging material. They do not
adequately cushion the instrument or prevent it from shifting in the carton.
They may also cause instrument damage by generating static electricity.
3
Pack the instrument in the original shipping containers. Original materials are
available through any Agilent Technologies office. Or, use the following
guidelines:
• Wrap the instrument in antistatic plastic to reduce the possibility of damage
caused by electrostatic discharge.
• For instruments weighing less than 54 kg (120 lb), use a double-walled, cor-
rugated cardboard carton of 159 kg (350 lb) test strength.
• The carton must be large enough to allow approximately 7 cm (3 inches) on
all sides of the instrument for packing material, and strong enough to accommodate the weight of the instrument.
• Surround the equipment with approximately 7 cm (3 inches) of packing ma-
terial, to protect the instrument and prevent it from moving in the carton. If
packing foam is not available, the best alternative is S.D-240 Air Cap™ from
1-11
Getting Started
Returning the Instrument for Service
Sealed Air Corporation (Commerce, California 90001). Air Cap looks like a
plastic sheet filled with air bubbles. Use the pink (antistatic) Air Cap™ to
reduce static electricity. Wrapping the instrument several times in this material will protect the instrument and prevent it from moving in the carton.
4
Seal the carton with strong nylon adhesive tape.
5
Mark the carton “FRAGILE, HANDLE WITH CARE”.
6
Retain copies of all shipping papers.
1-12
2
Modulating the Output Light 2-3
Performing Stimulus-Response Measurements 2-4
To characterize a passive device 2-6
Ambient Light Suppression 2-8
To suppress ambient light 2-9
Cleaning Connections for Accurate Measurements 2-11
Making Measurements
Making Measurements
Making Measurements
Making Measurements
In this chapter, you’ll find examples of making measurements using the
Agilent 83437A. These examples use your Agilent 83437A in conjunction with
an Agilent 71450/1/2B optical spectrum analyzer. Because of the
Agilent 83437A’s relatively high power density, the optical spectrum analyzer
can sweep much faster than if a white light source or surface emitting LED
were used.
The last section of this chapter explains how to maintain top performance of
your instrument by using proper handling and cleaning techniques. Be sure to
read this section before using your Agilent 83437A.
2-2
Modulating the Output Light
Making Measurements
Modulating the Output Light
The rear panel of the instrument is equipped with a
tor for each installed source. You can use these connectors to digitally modulate the source or completely disable its output light.
Digital modulation requires a TTL compatible signal. Modulation rates can
range from DC to 100 kHz. A “high” TTL value turns the source on. A “low”
TTL value turns the source off. The following schematic shows the input circuitry for each
If you want to turn a source off, simply connect a BNC short to the rear-panel
modulation input. You can order a BNC short from Agilent Technologies using
the following part number: 1250-0774.
MODULATION INPUT
connector.
MODULATION INPUT
connec-
2-3
Making Measurements
Performing Stimulus-Response Measurements
Performing Stimulus-Response Measurements
This section shows you how to perform stimulus-response measurements. The
more wavelength options your Agilent 83437A has installed, the wider the
wavelength range that can be measured. The combination of using the
Agilent 83437A for broadband stimulus and the optical spectrum analyzer for
selective response provides the following benefits:
• All wavelengths are available simultaneously
• Fast measurement speeds
• Small coherence length
• High dynamic range and high resolution
Measurements for DWDM systems
The following figure shows a system which is well suited for characterizing
dense wavelength-division multiplexed (DWDM) components. These include
devices such as phased arrays and add and drop demultiplexers.
The polarization controller is used to characterize polarization dependencies
of a device. For example, the center wavelength shift or the polarization
dependent loss of a demultiplexer. Because the Agilent 83437A emits unpolarized light, if you need polarized light, add a polarizer.
Increasing wavelength accuracy
When measuring deep-notch filters, increased absolute wavelength accuracy
may be required. To increase wavelength accuracy, the combination of an
Agilent 8168E/F tunable laser source and the Agilent 86120A multi-wavelength meter can be used to calibrate the optical spectrum analyzer. Simply
enter the difference between the two wavelength readings (optical spectrum
analyzer and multi-wavelength meter) into the optical spectrum analyzer as a
correction factor. Refer to the user’s guide for the optical spectrum analyzer to
learn how to enter correction factors. If you use this technique, be aware that
the Agilent 8168E/F measures wavelength in a vacuum and the optical spectrum analyzer measures wavelength in air unless you change its settings.
2-4
Making Measurements
Performing Stimulus-Response Measurements
Characterizing an optical amplifier
In addition to the measurement described in this section, the Agilent 83437A
is an ideal broadband light source for measuring the noise-gain profile of optical amplifiers. This allows you to accurately predict the amplifier’s perfor-
mance in a 4, 8, or 16 channel DWDM systems. The Agilent 71452B optical
spectrum analyzers is ideal for performing these measurements. For more
information, refer to Agilent Technologies product notes 71452-1, -2, and -3
which are available from your local Agilent Technologies service office.
2-5
Making Measurements
Performing Stimulus-Response Measurements
To characterize a passive device
1
Turn on the optical spectrum analyzer and the Agilent 83437A, and allow them
to warm up for 1 hour.
2
Use a fiber optic cable to connect the Agilent 83437A’s output to the input of
the optical spectrum analyzer.
3
On the optical spectrum analyzer, press
AUTO ALIGN
4
On the optical spectrum analyzer, use the
wavelength range.
5
Press
6
Press
beyond this value if needed.
7
If you are measuring a deep-notch filter, more sensitivity may be required.
Perform the following steps:
a
Press
b
Press
These steps cause the optical spectrum analyzer to compensate for the effect
of stray light inside the analyzer’s monochromator.
8
Press
9
Press
If changes to wavelength range or resolution bandwidth are made after this
trace is stored, repeat this step.
2-6
.
REF LEVEL
SENS,
State
STORE THRU->B,
, and set the reference level to –30 dBm.
and set the sensitivity to –70 dBm. You can increase the sensitivity
Amptd
BW,Swp
instr modes
,
MORE
,
, and then
SWPTIME AutoMan
,
, and then
and then
CHOP On
STM/RESP
NORM On Off
INSTR PRESET, AUTO MEAS,
START
so that On is underlined.
, and set the sweep time to 50 seconds.
.
to normalize the response.
and
STOP
keys to set the proper
and then
Making Measurements
Performing Stimulus-Response Measurements
10
Insert the device you are testing between the optical spectrum analyzer and the
Agilent 83437A.
11
NORMAL ON/OFF
Press
to turn the marker on. Rotate the front-panel knob to
read the values along the response.
2-7
Making Measurements
Ambient Light Suppression
Ambient Light Suppression
Ambient light can add significant errors to optical power measurements. This
is especially true when you are using or characterizing open beam devices.
The following example shows how the combination of the Agilent 83437A and
an Agilent 71450/1/2B optical spectrum analyzer can be used to eliminate this
error. The picture below shows the optical spectrum analyzer’s display. The
top trace shows the amplitude contribution from ambient light. The bottom
trace was captured after performing the procedure in this section.
In order to perform this measurement, the Agilent 83437A’s output is modulated at 270 Hz. Because, the optical spectrum analyzer has the ability to synchronize its data acquisition with the modulated light it can subtract out the
effects of ambient light. To learn more about using the optical spectrum analyzer’s adc trigger feature, refer to Agilent Technologies Product Note
71452–4, “Pulsed or Time-Dependent Optical Spectra Measurements.”
2-8
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