User's Guide HP 81531A Sensor Module SERIAL NUMBERS This manual applies to all instruments. ABCDE HP Part No.
Control Serial Number: Edition 2 applies directly to all instruments.
Safety Considerations Before operation, you should 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, you should keep it until you have checked the contents of the shipment for completeness and veri ed the module both mechanically and electrically.
Caution A maximum of 15V can be applied as an external voltage to any BNC connectors. Storage and Shipment The module can be stored or shipped at temperatures between 040 C and +70 C. The module should be protected from temperature extremes that may cause condensation within it.
Contents C. HP 81531A Speci cations Supplementary Performance Characteristics . . . . . . . . . . . Analog output: . . . . . . . . . . . . . . . . . . . . . . . D. Performance Tests Introduction . . . . . . . . . Equipment Required . . . . Test Record . . . . . . . . . Test Failure . . . . . . . . . Instrument Speci cation . . . Performance Test . . . . . . Accuracy and Linearity Test Test Setup . . . . . . . . I. Accuracy Test . . . . . II. Linearity Test . . . . . III. Noise Test . . . . . . . . . . .
Figures D-1. Accuracy and Linearity Test Setup . . . . . . . . . . . . . . D-2. Addition of results (example) . . . . . . . . . . . . . . . . .
C C HP 81531A Speci cations Speci cations describe the instrument's warranted performance. 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.
C HP 81531A Speci cations Sensor Element Wavelength range Power range Display resolution In GaAs 800-1700nm +3 to -90dBm dBm, dB 0.001 0.0001 on printout Watt 0.01 to 10 (depending on power range) Applicable ber type 9/125 m - 100/140 m, NA 0.3 Uncertainty (Accuracy) 62.5% (1000-1650nm)[1] Total Uncertainty 65%61.5pW (1000-1650nm)[2] Linearity (0 to -70dBm) 18 C to 28 C const. temp 60.015dB61pW 0 C to 55 C const. temp 60.05dB61.5pW Noise <1.5pW (1200-1600nm) peak-peak, avg.
C Ambient temperature 0 to 55 C, non-condensing. Within 1 year after calibration, add 0.3% for second year. For Biconic Connector add 61%. Supplementary Performance Characteristics Add 1% to total uncertainty for the full wavelength range. Outside the speci ed wavelength range, the noise increases by up to 5 times the value shown above. Analog output: Bandwidth: DC, 300 to 400Hz, depending on range and sensor module. Output voltage: 0 to 2V into open. Output impedance: 600 typical. Max.
D Performance Tests Introduction The procedures in this section test the performance of the instrument. The complete speci cations to which the HP 81531A is tested are given in Appendix C. All tests can be performed without access to the interior of the instrument. The test equipment given corresponds to tests carried out with Diamond HMS-10/HP conectors. Equipment Required Equipment required for the performance test is listed in the table below.
D Test Record Results of the performance test may be tabulated on the Test Record provided at the end of the test procedures. It is recommended that you ll out the Test Record and refer to it while doing the test. Since the test limits and setup information are printed on the Test Record for easy reference, the record can also be used as an abbreviated test procedure (if you are already familiar with the test procedures).
Performance Test D The performance test given in this section includes the Accuracy Test, the Linearity Test, and the Noise Test. Perform each step in the order given, using the corresponding test equipment. Note Make sure that all optical connections of the test setups given in the procedure are dry and clean. DO NOT USE INDEX MATCHING OIL.
D Figure D-1. Accuracy and Linearity Test Setup 3. Turn the instruments on, enable the laser source and allow the instruments to warm up for at least 20 minutes. Note The linearity test must only be performed at either 1300nm or 1550nm. The accuracy test must be performed in the -20dBm range at 10 W at both 1300nm and 1550nm. I. Accuracy Test 1. On both power meters: a. Set the calibration factor to zero. b. Set the wavelength to the wavelength of the laser source. c. Set the instruments into MEAS mode.
II. Linearity Test 1. Make sure that the HP 8156A output is disabled. ZERO the DUT. 2. Enable the HP 8156A output. 3. On the DUT, switch o autoranging and select the -20dBm range. Set the display to show results in dBm. 4. Alter the attenuation until the DUT displays -17.4dBm. 5. Press 4Disp!Ref5, then 4dB5. 6. Press 4Up5 to select the -10dBm range. 7. Note the deviation, displayed in dB, as R1 on the test record. a. In the -10dBm range. Set the display to show results in dBm. b.
Example Results for the Linearity test D Test Minimum Maximum Measurement No. Test Description Spec. Result Spec. Uncertainty II. Linearity Test dB Range Power (dBm) -20dBm -17.4 Disp!Ref -10dBm 0.004 =R1 -10dBm 0dBm -7.4 Disp!Ref -20dBm -30dBm -27.4 Disp!Ref -30dBm -40dBm -37.4 Disp!Ref -40dBm -50dBm -47.4 Disp!Ref D-6 Performance Tests -0.008 =R2 -0.008 =R3 -0.004 =R4 0.
Example Calculated Results for the Linearity Test Test No. Test Description Non-Linearity Range Minimum Spec. Result Maximum Measurement Spec. Uncertainty Formula 0dBm R1+R2 -0.015dB -0.004dB +0.015dB 60.006dB -10dBm R1 -0.015dB 0.004dB +0.015dB 60.006dB -20dBm 60.00dB 0.000dB -30dBm R3 -0.015dB -0.008dB +0.015dB 60.006dB -40dBm R3+R4 -0.015dB -0.012dB +0.015dB 60.008dB -50dBm R3+R4+R5 -0.015dB 0.008dB +0.015dB 60.
D III. Noise Test Note The noise measurement must be performed with either a module or a blank panel in the second channel position. Connect the equipment as shown in Figure D-1. Disable the HP 8156A output. On the DUT, select AUTOranging, and display in Watts. Set the averaging time to 1s. Press 4Zero5. Select the MENU mode. Press 4Record5, to select Stability. Press 4Edit5 and select the T_TOTAL parameter. Set T_TOTAL to 1 minute. Press 4Edit5, and then 4Exec5 to run the noise measurement.
Performance Test for the HP 81531A Page 1 of 4 Test Facility: Report No. Date Customer Tested By Model HP81531A Sensor Module Serial No. Ambient temperature C Options Relative humidity % Firmware Rev.
Performance Test for the HP 81531A D Page 2 of 4 Test Equipment Used: Description Model No. 1. Lightwave Multimeter (Std.) HP 8153A 2. Opt. Head Interface Module HP 81533A 3. Optical Head HP 81524A 4a1. CW Laser Source HP 81552SM 4a2. CW Laser Source HP 81553SM 4b. CW Laser Source HP 81554SM 5. Optical Attenuator Trace No. Cal. Due Date 6. Lightwave Multimeter (DUT) HP 8156A Opt.101 HP 8153A 7. Connector Interface HP 81000AI N/A N/A 8. Connector Adapter HP 81000AA N/A N/A 9.
Performance Test for the HP 81531A Model HP 81531A Sensor Module Test No. Test Description I. Accuracy Test No. Minimum Spec. Date Result W Page 3 of 4 Maximum Measurement Spec. Uncertainty measured at nm Output Power 9.72 W 10.28 W 62% measured at nm Output Power 9.72 W 10.28 W 62% II. Linearity Test Range Power (dBm) -20dBm -17.4 Disp!Ref -10dBm -10dBm 0dBm -7.4 Disp!Ref -20dBm -30dBm -27.4 Disp!Ref -30dBm -40dBm -37.4 Disp!Ref -40dBm -50dBm -47.
Performance Test for the HP 81531A D Model HP 81531A Sensor Module No. Test Minimum No. Test Description Spec. Result Non-Linearity Range Page 4 of 4 Date Maximum Measurement Spec. Uncertainty Formula 0dBm R1+R2 -0.015dB dB +0.015dB 60.006dB -10dBm R1 -0.015dB dB +0.015dB 60.006dB -20dBm 0.000dB 0.00dB -30dBm R3 -0.015dB dB +0.015dB 60.006dB -40dBm R3+R4 -0.015dB dB +0.015dB 60.008dB -50dBm R3+R4+R5 -0.015dB dB +0.015dB 60.010dB III. Noise Test pW <1.
E Cleaning Procedures E 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.
Pipe-cleaner E Compressed Air 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. 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.
Other Cleaning Tools To examine devices you also require: Microscope Select a microscope with a magni cation range of between 50X and 300X. These should be available from photographic stores or laboratory suppliers. Ensure that the light source of the microscope is exible. This helps you to examine your device closely and from di erent angles. A microscope allows you to determine the type of dirt on your device and its extent.
Preserving Connectors E Listed below are some hints on how to keep your connectors in the best possible condition. Making Before you make any connection you must ensure that all cables and Connections connectors are clean. If they are dirty, use the appropriate cleaning procedure. When inserting the ferrule of a patchcord into a connector or an adapter, make sure that the ber end does not touch the outside of the mating connector or adapter.
Correct Cleaning Procedure If you are unsure about the correct cleaning procedure for your device or if you are unsure whether the procedure given here is suitable for your device, check with the manufacturer or sales distributor, or try the procedure on a dummy or test device rst. E Cleaning Cable Connectors Cleaning connectors is di cult as the core diameter of a singlemode ber is only about 9 m. This generally means you cannot see streaks or scratches on the surface.
Cleaning Connector Adapters E Caution Some adapters have an anti-re ection coating on the back to reduce back re ection. This coating is extremely sensitive to solvents and mechanical abrasion. Extra care is needed when cleaning these adapters. Preferred 1. Clean the adapter by rubbing a new, dry cotton-swab over the surface using a small circular movement. Procedure 2. Blow away any remaining lint with compressed air.
How to clean instruments with a recessed lens interface Light dirt If you nd any particles of dirt on the xed connector interface, or on the input of the optical block, clean them with compressed air. This cleaning method is gentle to your optical device and is an ideal approach if there is no fat on the surface of your device. Heavy dirt Using compressed air, blow away larger particles of dirt. Clean the recessed lens interface with a dry cotton swab by rubbing gently over its surface.
