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Message ID: 13940     Entry time: Mon Jun 11 17:18:39 2018
Author: pooja 
Type: Update 
Category: Cameras 
Subject: CCD calibration 

Aim: To calibrate CCD of GigE using LED1050E.

The following table shows some of the specifications for LED1050E as given in Thorlabs datasheet.

Specifications Typical maximum ratings
DC forward current (mA)   100
Forward voltage (V) @ 20mA (VF) 1.25 1.55
Forward optical power (mW) 1.6  
Total optical power (mW) 2.5  
Power dissipation (mW)   130

 The circuit diagram is given in Attachment 1.

Considering a power supply voltage Vcc = 15V, current I = 20mA & forward voltage of led VF = 1.25V, resistance in the circuit is calculated as,

R = (Vcc - VF)/I = 687.5\ohm\ohms\Omega

Attachment 2 gives a plot of resistance (R) vs input voltage (Vcc) when a current of 20mA flows through the circuit. I hope I can proceed with this setup soon.


Attachment 1: led_circuit.pdf  9 kB  Uploaded Mon Jun 11 19:03:52 2018  | Hide | Hide all
Attachment 2: R_vs_V.pdf  11 kB  Uploaded Mon Jun 11 20:23:49 2018  | Hide | Hide all
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