ILX Lightwave LDX-36000 Series User Manual

CALIBRATION AND TROUBLESHOOTING
Photodiode Current (PDI) Measurement
130 LDX-36000 Series
CHAPTER 6

Photodiode Current (PDI) Measurement
To perform an accurate photodiode calibration, large resistor values are
recommended.
1 Set the 36000 display to Power Photodiode by sending the following command:
LAS:DIS:PPD
2 Set the PD Bias to 0 Volts by sending the following command: LASER:PDBIAS 0
3 Set the user photodiode calibration to 0 by sending the following command:
LAS:CALPD 0
4 Set the factory photodiode calibration to default values by sending the following
command: LAS:CAL:MDI 1,0
5 Connect a current source to the photodiode input pins in the DB9 connector on the back
of the 36000. Set the current source to 20% of full scale (2 mA)
6 Record the 36000’s photodiode current measurement with the following command:
LAS:PPD?
7 Set the current source current to 80% of full scale (8 mA)
8 Record the 36000’s photodiode current measurement with the following command:
LAS:PPD?
9 Calculate the slope and offset of the photodiode current measurement with the following
equations:
slope = (80% Setpoint Current Value - 20% Setpoint Current Value) / (36000 80%
measurement - 36000 20% measurement)
offset = 80% Setpoint Current Value - (slope * 36000 80% measurement)
10 Send the photodiode measurement calibration to the 36000 using the following command:
LAS:CAL:MDI slope,offset
11 Set the current on the current source to 50% of full scale ( 5 mA)
12 Retrieve the 36000’s photodiode current measurement with the following command:
LAS:PPD?
13 Verify that the photodiode current measurement is within the accuracy specifications of
the instrument

ILX Lightwave LDX-36000 Series Specifications

General

Brand	ILX Lightwave
Model	LDX-36000 Series
Category	Portable Generator
Language	English