HP HP 81551MM User manual

Operating and Programming Manual
HP 81551MM Lightwave
Multimeter Source Module
SERIAL NUMBERS
This manual applies to all instruments.
ABCDE
HP Part No. 81551-90011
Printed in the Federal Republic of Germany
Second Edition
E1294

Control Serial Number: Edition 2 applies directly to all instruments.
Edition 1 : 1st May 1990 : 81551-90011 : E0590
Edition 2 : 1st November 1990 : 81551-90011 : E1190
1st August 1991 : 81551-90011 : E0891
1st December 1994 : 81551-90011 : E1294

Safety Considerations
Before operation, review the instrument and manual, including the red safety
page, for safety markings and instructions
.You must follow these to ensure safe
operation and to maintain the instrument in safe condition.
Initial Inspection
Inspect the shipping container for damage. If there is damage to the container
or cushioning, keep them until you have checked the contents of the shipment
for completeness and veried the instrument both mechanically and electrically.
The Performance Tests give procedures for checking the operation of the
instrument. If the contents are incomplete, mechanical damage or defect is
apparent, or if an instrument does not pass the operator's checks, notify the
nearest Hewlett-Packard oce.
Warning
To avoid hazardous electrical shock, do not perform
electrical tests when there are signs of shipping damage to
any portion of the outer enclosure (covers, panels, etc.).
Line Power Requirements
The HP 81551MM operates when installed into the HP 8153A Lightwave
Multimeter mainframe
Operating Environment
The HP 8153A safety information summarizes the HP 81551MM operating
environment ranges. In order for the HP 81551MM to meet specications, the
operating environment must be within the limits specied for the HP 8153A.
Storage and Shipment
The module can be stored or shipped at temperatures between 0 40

C and
+70

C. Protect the module from temperature extremes that may cause
condensation within it.
iii

Initial Safety Information for Laser Source Modules
The specications for these modules are as follows:
HP 81551MM
Laser Type FP-Laser
InGaAsP
Laser Class
According to IEC 825-1 3A
(not USA)
(EN 60825-1 Europe)
According to 21 CFR 1040.10 1
(USA)
Output Power > -2dBm
Beam Diameter 50  m
Numerical Aperture 0.2
Wavelength 850 6 10nm
iv

Sicherheitsinformation f  ur Laser Quellen
Die Spezikationen f ur die Lasereinsch ube sind wie folgt:
HP 81551MM
Laser Typ FP-Laser
InGaAsP
Laser Klasse
Entsprechend IEC 825-1 3A
(EN 60825-1 Europa)
Ausgangsleistung > -2dBm
Strahldurchmesser 50  m
Numerische Apertur 0.2
Wellenl 
ange 850 6 10nm
v

Informations et Consignes de S  ecurit  e Relatives  a l'Utilisation
des Lasers.
Les Sp ecications des Modules Laser sont les Suivantes:
HP 81551MM
Type de Laser FP-Laser
InGaAsP
Classe du Laser
Conforme au STD IEC 825-1 3A
(EN 60825-1 Europe)
Puissance de Sortie > -2dBm
Diam ^ etre du Faisceau 50  m
Ouverture Num  erique 0.2
Longueur d'Onde 850 6 10nm
vi

Contents
C. HP 81551MM Specications
Suppelementary Performance Characteristics .... .. .. .. C-2
Internal Digital Modulation . . . . . . . . . . . . . . . . . . C-2
Output Attenuation .. .. .. .. .. .. .. .. .. .. . C-2
Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
Spectral Bandwidth (FWHM) ................. C-2
D. HP 81551MM Performance Tests
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . D-1
Equipment Required . . . . . . . . . . . . . . . . . . . . . . D-1
Test Record .......................... D-2
Test Failure .......................... D-2
Instrument Specication .. .. .. .. .. .. .. .. .. .. D-2
Performance Tests . . . . . . . . . . . . . . . . . . . . . . . D-2
Output Power and Stability Tests .... .. .. . .. .. .. D-3
Output Power Test.... .. .. .. .. .. .. .. .. . D-3
Attenuation Function Test .... .. .. .. .. .. .. . D-4
Modulation Function Test .... .. .. .. .. .. .. . D-4
Stability Test ........................ D-4
E. Cleaning Procedures
The Cleaning Kit . . . . . . . . . . . . . . . . . . . . . . . . E-1
Other Cleaning Tools . . . . . . . . . . . . . . . . . . . . . E-3
Preserving Connectors . . . . . . . . . . . . . . . . . . . . . E-4
Cleaning Instrument Housings ................. E-4
Cleaning Procedures . . . . . . . . . . . . . . . . . . . . . . E-5
Cleaning Cable Connectors . . . . . . . . . . . . . . . . . . E-5
Cleaning Connector Adapters . . . . . . . . . . . . . . . . . E-6
Cleaning Connector Interfaces ................ E-6
Contents-1

Figures
D-1. Performance Test Setup ................... D-3
Tables
C-1. HP 81551MM Specications . . . . . . . . . . . . . . . . . . C-1
Contents-2

C
HP 81551MM Specications
Specications describe the instrument's warranted preformance. Supplementary
performance characteristics describe the instrument's non-warranted typical
performance.
Because of the modular nature of the instrument, these performance
specications apply only to this module.You should insert these pages into the
appropriate section of the manual.
Table C-1. HP 81551MM Specications
Laser Type Fabry Perot Laser
Central Wavelength
1
850 6 10nm
Fiber type multimode, 50/125  m
Spectral Bandwidth
2
< 1.5nm rms
Output Power
2
> -2dBm
CW-Stability
Short Term (15min, T=constant) 6 0.01dB
Long Term (6h, T= 0

Cto55

C 6 1K) 6 0.06dB
Operating temperature 0

C to +55

C
Dimensions 75mm H, 32mm W, 335mm D (2.8 " 2 1.3 " 2 13.2 " )
Weight net 0.7kg (1.5lbs), shipping 1kg (2.2lbs)
Recalibration Period 1 year
1
Central Wavelength is shown on the display.
2
rms: root mean square.
3
Class 3A according to IEC 825-1 (1993), Class 1 according to FDA CFR 21 (1986)
4
After a warm-up time of 60 min. with output enabled. If previously stored at
the same temperature, 20 min. only.
HP 81551MM Specications C-1

Suppelementary Performance Characteristics
Internal Digital Modulation
You can select internal modulation frequencies of 270HZ, 1kHz, or 2kHz. All
outputs are pulse shaped, with a duty cycle of 50%.
Output Attenuation
The output can be attenuated from 0 to 6dB, in steps of 0.1dB.
Stability
The value of the long term CW-stability doubles with just one minute warmup
time (laser enabled).
Spectral Bandwidth (FWHM)
The spectral bandwidth is, typically, twice the specied RMS value.
C-2 HP 81551MM Specications

D
HP 81551MM Performance Tests
Introduction
The procedures in this section test the optical performance of the instrument.
The complete specications to which the HP 81551MM is tested are given in
Table C-1 . All tests can be preformed without access to the interior of the
instrument. The performance tests refer specically to tests using the Diamond
HMS-10/HP connector.
Equipment Required
Equipment required for the performance test is listed below. Any equipment
that satises the critical specications of the equipment given in the list may be
substituted for the recommended models.
Instrument/Accessory Recommended Model
Power Meter Standard HP 8153A Mainframe with
HP 81533A Optical Head Interface Module with
HP 81520A Optical Head
Multimeter Mainframe HP 8153A
Connector Adapter
(head)
HP 81000AA
Connector Interface HP 81000AI 2ea (08154-61701)
Multimode Fiber HP 81501AC
BNC to BNC Cable 8120-1840
Oscilloscope
HP 81551MM Performance Tests D-1

Test Record
Results of the performance test may be noted in the P
erformance Test Record.
The Test Record can also be used as a permanent record and may be reproduced
without written permission from Hewlett-P
ackard
Test Failure
If the HP 81551MM fails any performance test, return the instrument to the
nearest Hedwlett-Packard Sales/Service Oce for repair.
Instrument Specication
Specications are the performance characteristics of the instrument that
are caertied. These specication, listed in Table C-1, are the perfornamce
stahdards or limits agains which the HP 81551MM can be tested. Appendix C
also lists some supplemental characteristics of the HP 81551MM and should be
considered as additional information.
Any changes in the specications due to manufacturing changes, design, or
traceability to the National Bureau of Standards will be covered in a manual
change supplement or revised manual. the specications listed in such a change
supercede any previously published.
Performance Tests
The performance tests given in this section are separated into Output Power
Test and Stability Test. Perform each step in the tests in the order they are
given, using the corresponding test equipment.
Note
Make sure that all optical connections in the test setups given in
the procedure are dry and clean.
D-2 HP 81551MM Performance Tests

The ambient temperature must be constant ( 6 2

C) during the
test. The power meter must be zeroed before the measurement.
Output Power and Stability Tests
Specications:
Optical output power of 50/125
 m ber: > -2dBm
Stability over 15 minutes at constant temperature:
6 0.01dB
Stability over 6h and 6 2

C env. temp. window: 6 0.06dB
Output Power Test
1. Make sure that cable connectors and detector windows are clean.
2. Turn instruments on, enable the laser output of the HP 81551MM and allow
instruments to warm up for at least 20 minutes.
3. On the power meter:
a. Set  to the wavelength displayed for the HP 81551MM source channel.
b. Make sure that the CAL parameter on the power meter is set to zero
.
c. With the connector adapter, on the optical head, coverd with a plastic
cap, press 4
Zero
5 to zero the power meter.
4. Connect the equipment as shown in Figure D-1.
Figure D-1. Performance Test Setup
HP 81551MM Performance Tests D-3

5. On the HP 8153A with the module under test:
a. Press 4
Param
5 until the AUX parameter is selected. Make sure that this
parameter is set to CW .
b. Press 4
Param
5 until the ATT parameter is selected. Make sure that this
parameter is set to zero.
6. Measure the output power and note the result in the Test Record.
Attenuation Function Test
7. On the power meter, press 4
Disp ! Ref
5 . Press 4
dB
5 to select a display in dB.
8. Using the modify keys on the HP 8153A with the module under test,
increase the attenuation and check that the output power changes.
Note the reaction on the Test Record.
9. Set the attenuation to 1.0dB.
Modulation Function Test
10. Using a BNC cable, connect the power meter transducer output to the
oscilloscope input and set the oscilloscope as follows: 0.5V/DIV DC coupled,
1ms/DIV.
11. On the power meter, switch the autoranging o and select the 0dBm range.
12. On the HP 8153A with the module under test, press 4
Param
5 to select the AUX
parameter. Monitor the frequency change on the oscilloscope as you set the
modulation to 270Hz, 1kHz, and then to 2kHz.
Note the reaction on the Test Record.
Stability Test
1. Enable the HP 81551MM laser output and allow the instruments to warm up
for 20 minutes.
2. Select the channel with the source.
a. Press 4
Param
5 to select the AUX parameter. Set this parameter to CW .
b. Press 4
Param
5 to select the ATT parameter. Set this parameter to zero.
D-4 HP 81551MM Performance Tests

3. On the power meter:
a. Cover the input to the sensor with a plastic cap and press
4
Zero
5 to zero the
meter.
b. Press 4
Param
5 to select the  parameter. Set this parameter to the value
displayed for the source.
c. Press 4
Param
5 to select the T parameter. Set this parameter to 1s .
4. Using the HP 81501AC cable, connect the output of the source to the input
of the sensor. Make sure that the cable is xed and that it cannot be moved
during the measurement.
5. Select the MENU mode on the power meter.
a. Press 4
Record
5 to select STABILTY .
b. Press 4
Edit
5 and select the T_TOTAL parameter. Set the T_TOTAL parameter
to 15 minutes.
c. Press 4
Edit
5 and then 4
Exec
5 to run the stability application.
6. When the stability test has completed, press 4
More
5 to select the SHOW
application. Press 4
Edit
5 and then 4
Next
5 / 4
Prev
5 to display the DIFF result.
Divide this result by 2 to obtain the value for the stability:
DI F F
2
= S tabil ity ( dB )
Note the result on the Test Record.
7. Repeat the stability measurement (steps 5 and 6) with T_TOTAL set to 6
hours.
HP 81551MM Performance Tests D-5

Performance Test for the HP 81551MM
Page 1 of 3
Test Facility:
Report No.
Date
Customer
Tested By
Model HP 81551MM Source Module
Serial No. Ambient temperature

C
Options Relative humidity %
Firmware Rev. Line frequency Hz
Special Notes:
D-6 HP 81551MM Performance Tests

Performance Test for the HP 81551MM
Page 2 of 3
Test Equipment Used:
Description Model No. Trace No. Cal. Due Date
1. Lightwave Multimeter (Std.) HP 8153A
2. Opt. Head Interface Module HP 81533A
3. Optical Head 850nm HP 81520A
4. Lightwave Multimeter (DUT) HP 8153A
5. Connector Interface HP 81000AI N/A N/A
6. Connector Adapter HP 81000AA N/A N/A
7. Multimode Fiber HP 81501AC N/A N/A
8. BNC to BNC Cable P/N 8120-1840 N/A N/A
9. Oscilloscope
10.
11.
12.
13.
14.
15.
16.
17.
18.
HP 81551MM Performance Tests D-7

Performance Test for the HP 81551MM
Page 3 of 3
Model HP 81551MM Source Module No. Date
Test Minimum Maximum Measurement
No.Test Description Spec. Result Spec. Uncertainty
1. Output Power Test
Output Power -2dBm 0.1dB
2. Attenuation Function Test
Passed (P)/Failed (F)
3. Modulation Function Test
Passed (P)/Failed (F)
4. Stability Tests
Stability (15min.) -0.01dB +0.01dB
Stability (6h.) -0.06dB +0.06dB
D-8 HP 81551MM Performance Tests

E
Cleaning Procedures
The Cleaning Kit
A full cleaning kit contains the following items:
Isopropyl alcohol This is usually available from pharmaceutical suppliers or chemists
.
If possible, use alcohol supplied for medical purposes, rather than impure
alcohol or alcohol with additives.
Caution
Do not use other solvents as some can damage plastic materials and claddings.
For example,Acetone dissolves the adhesives used in ber optic devices.
Warning
Never drink this alcohol as this can lead to blindness or other serious damage
to your health.
Cotton-swabs Use swabs such as Q-tips or other cotton-swabs. These are typically available
from local distributors of medical or hygiene products (such as supermarkets or
pharmacies).
Note If you are cleaning connector interfaces or adapters, the diameter of the
cotton swab is important. Cotton swabs for babies normally have a smaller
diameter.
Caution
Do not use foam swabs, as these can leave lmy deposits on the surface you
are cleaning.
Store your cotton-swabs carefully and never reuse them. Dust and dirt from
the air or from previous cleaning, can scratch or dirty your optical device.
Soft-tissues These are available from most stores and distributors of medical and hygiene
products (such as supermarkets or pharmacies).
Use multi-layer tissues made from non-recycled cellulose. These are more
absorbent and softer than other types and they do not scratch the surface of
your device.
Caution
Store your soft-tissues carefully and never reuse them, as dust and dirt from
the air or from previous cleaning can scratch and dirty your optical device.
Cleaning Procedures E-1

Pipe-cleaner This is available from tobacco shops.
Ensure that the bristles of the pipe-cleaner are soft, so that they do not scratch
your device during cleaning.
Caution
Store your pipe-cleaners carefully and never reuse them as dust and dirt from
the air or from previous cleaning can scratch and dirty your optical device.
Compressed Air This is available from laboratory suppliers.
It is essential that your compressed air is free of dust, water and oil. Only use
clean, dry air. If you do not, it can lead to lmy deposits or scratches.
When using compressed air from a can,
Hold the can upright. A slant can cause propellant to escape with the
compressed air and dirty your optical device.
Spray the rst couple of seconds into the air, as the rst stream of
compressed air can contain condensation or propellant. Any condensation
produces a lmy deposit.
If you are using compressed air from a can, you should select one with a
CFC-free propellant, for the sake of the environment.
E-2 Cleaning Procedures