Keithley 2520INT, Быстрый старт

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2-8 Getting Started Model 2520INT Quick Start Guide
Typical responsivity values are summarized in Table 2-3 .
Measuring dark current
1. Connect the Model 2520INT to the desired Model 2520 detector channel.
2. 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.
3. From the Model 2520 front panel, press the CONFIG FILTER key.
4. Enter the number of readings to average (1-100).
5. Turn on the outputs, then press TRIG.
6. Note the detector current reading.
Optical power measurements
Optical power calculation
Optical power is calculated as follows:
Optical power = (I
measured
- I
dark current
)/Responsivity
Where: I
measured
= measured photodiode current (amps)
I
dark current
= photodiode dark current in amps (see above)
Responsivity = amps/watt (see supplied Model 2520INT calibration constants)
Table 2-3
Typical sphere responsivity
Sphere
Typical Responsivity
( m A/W)
980nm 1550nm
Germanium 3.5 7.5