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Entry  Wed Apr 21 21:56:27 2010, Kevin, Update, PSL, Innolight 2W Vertical Beam Profile bp2.jpgbp2.dat
    Reply  Wed Apr 21 22:11:48 2010, rana, Update, PSL, Innolight 2W Vertical Beam Profile 
    Reply  Wed Apr 21 23:35:37 2010, Koji, Update, PSL, Innolight 2W Vertical Beam Profile 
    Reply  Thu Apr 22 21:42:24 2010, Alberto, Update, PSL, Innolight 2W Vertical Beam Profile 
Message ID: 2829     Entry time: Wed Apr 21 22:11:48 2010     In reply to: 2828
Author: rana 
Type: Update 
Category: PSL 
Subject: Innolight 2W Vertical Beam Profile 

Back in Gainesville in 1997, I learned how to do this using the chopper wheel. We had to make the assumption that the wheel's blade was moving horizontally during the time of the chop.

One advantage is that the repetitive slices reduces the random errors by a lot - you can trigger the scope and average. Another advantage is that you can download the average scope trace using USB, floppy, or ethernet instead of pencil and paper.

But, I never analyzed it in enough detail to see if there was some kind of nasty systematic error.

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