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Model 2520INT Integrating Sphere Quick Start Guide A G R E A T E R M E A S U R E O F C O N F I D E N C E...
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WARRANTY Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a period of 1 year from date of shipment. Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables, rechargeable batteries, diskettes, and documentation.
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Revision A (Document Number 2520INT-903-01) ............April 2002 All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc. Other brand names are trademarks or registered trademarks of their respective holders.
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Keithley products are designed for use with electrical signals that are rated Installation Category I and Installation Category II, as described in the International Electrotechnical Commission (IEC) Standard IEC 60664. Most measurement, control, and data I/O signals are Installation Category I and must not be directly connected to mains voltage or to voltage sources with high tran- sient over-voltages.
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To maintain protection from electric shock and fire, replacement components in mains circuits, including the power transformer, test leads, and input jacks, must be purchased from Keithley Instruments. Standard fuses, with applicable national safety ap- provals, may be used if the rating and type are the same. Other components that are not safety related may be purchased from other suppliers as long as they are equivalent to the original component.
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This series covers the offering of Integrating Spheres for use with the Model 2520 Pulser Test System. Products The following lists the current products in the 2520INT Series. Each product has bundled a CD Manual, Calibration report, and ¼-20 post and base.
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Outer Shield – Not Connect (Isolated from chassis) Photodiode Outer-most Shield (NC) Pulsed Operation The 2520INT supports the pulse capabilities of the 2520 Pulsed Laser Diode Test System. Fiber Tap Port Connector Type: SMA Numerical Aperature (NA): 0.22 (typ.) (µ µ µ µ m) 62.5...
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Based on detector being linear to up to 25mA photocurrent and on a Signal to Noise Ratio (SNR) ≥ 100. Calibration of the 2520INT is performed with an open fiber tap port. The power measurement will increase by approximately 1% with an SMA patch cord attached to the port.
Configuring the Model 2520 detector polarity for the Model 2520INT ..............2-6 Configuring the Model 2520 detector current measurement range for the Model 2520INT ....... 2-6 Remote instrument setup ............. 2-6 Detector dark current measurements .......... 2-7 Description ................2-7 Optical power measurements ..........
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List of Illustrations General Overview Figure 1-1 Model 2520INT configuration ..........1-5 Getting Started Figure 2-1 Detector terminals ..............2-2 Figure 2-2 Electrical connections ............. 2-3 Figure 2-3 Divergent beams ..............2-4 Figure 2-4 Collimated beams ..............2-4 Figure 2-5 Horizontal and vertical acceptance angle ........
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List of Tables General Overview Getting Started Table 2-2 Command summary for 2520INT connected to Detector 1 ... 2-7 Table 2-1 Remote voltage bias and detector polarity measurement commands to bias 2520INT ........... 2-7 Table 2-3 Typical sphere responsivity ............ 2-8...
Specifications Model 2520INT specifications shown at the front of this guide were current at the time of duplication, but they are subject to change without notice. For the most recent specifica- tions, refer to the web site at www.keithley.com.
Laser safety precautions WARNING While the Model 2520INT does not incorporate a laser, it is designed to be used with laser diode devices. The following safety practices must be used to protect operators and other users of this product from potential exposure to laser radiation: •...
Optional accessories The following accessory is available to make connections to the Model 2520INT. Triax cable The following cable is required to connect the Model 2520INT detector output to the input of the Model 2520 Pulsed Laser Diode Test System: •...
Model 2520INT Quick Start Guide General Overview Product overview The 2520INT series of integrating sphere-based detectors are specifically designed to pro- vide highly accurate light intensity measurements. The integrating sphere simplifies pro- duction testing of optical components by eliminating common measurement problems related to detector alignment, beam profile, polarization, and back reflection.
Model 2520 channel as follows: Connect one end of the Model 7078-TRX triax cable to the Model 2520INT detector output connector. Connect the other end of the Model 7078-TRX triax cable to the desired Model 2520 DETECTOR jack.
Connections to DUT Free space operation and alignment considerations For free space operation, position the Model 2520INT as close as possible to the DUT. Proper alignment of the Model 2520INT to the light source under test is important for optimum optical power measurement. Key considerations include divergent beams, colli- mated beams, and full beam collection.
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Getting Started Model 2520INT Quick Start Guide Figure 2-3 Divergent beams Detector Entrance Port Light Source Collimated beams Collimated beams differ from divergent beams in that the edges of the beam are parallel. As shown in Figure 2-4, the beam diameter stays constant even as the distance from the source increases.
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Model 2520INT Quick Start Guide Getting Started Full beam collection Full beam collection is important for optimum optical power measurement (Figure 2-5). The maximum acceptance angle of the sphere in the vertical direction is 45˚ half angle (divergence) from the entrance port. The maximum acceptance angle of the sphere in the horizontal direction is 25°...
The reverse bias reduces the capacitance of the detector in the 2520INT, which greatly speeds up the reaction time, permitting the 2520INT to respond to the 100 ns (or less) rise time of the Model 2520’s pulses. The recommended bias is -5V. The necessary trade off for using the bias is an increase in the dark current.
Set detector #2 measure range (0.01, 0.02, 0.05, 0.1). :SENSe3:CURRent:POLarity <polarity> Set detector #2 measure polarity. Programming example Table 2-2 summarizes the commands for the 2520INT connected to Detector 1. These commands set up the Model 2520 as follows: • Measurement range: 10mA •...
Measuring dark current Connect the Model 2520INT to the desired Model 2520 detector channel. Cover the optical input port of the Model 2520INT with a dust-free, lightproof cover. Light leakage will result in erroneous dark current measurements and will effect the overall accuracy of absolute power measurements.
Optical Power Measurements. 3. Enter 1/Responsivity (W/A) of sphere for device wavelength as M. Responsivity values are supplied with your 2520INT. Reference values are also given in Table 2-1. 4. Enter sphere dark current as B. 5. Select units as W for Watts.
2-10 Getting Started Model 2520INT Quick Start Guide Table 2-4 Remote MX+B commands used to calculate optical power Command Description :CALC2:KMAT:MBF <B_value> Set detector 1 B value for MX + B math. :CALC2:KMAT:MMF<M_value> Setdetector 1 M value for MX + B math.
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Model 2520INT Quick Start Guide Handling and cleaning precautions Dust Cover the optical port opening when not in use to prevent internal contamination of the Model 2520INT. Inconsistencies on the internal surface of the sphere will cause inaccura- cies in measurements. Cleaning •...
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Index range Remote instrument setup accessories alignment considerations Safety symbols and terms Saving and restoring user setups 2-10 Specifications Calibration Collimated beams Configuration Triax cable connections Connections to Model 2520 Contact information voltage bias current measurement polarity Warranty information detector current measurement range Detector dark current measurements Detector output terminals detector polarity...
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Service Form Model No. _______________ Serial No. __________________ Date _________________ Name and Telephone No. ____________________________________________________ Company _______________________________________________________________________ List all control settings, describe problem and check boxes that apply to problem. _________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ ❑ Intermittent ❑ Analog output follows display ❑...
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Specifications are subject to change without notice. All Keithley trademarks and trade names are the property of Keithley Instruments, Inc. All other trademarks and trade names are the property of their respective companies. Keithley Instruments, Inc. 28775 Aurora Road • Cleveland, Ohio 44139 • 440-248-0400 • Fax: 440-248-6168 1-888-KEITHLEY (534-8453) •...
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