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Entry  Wed May 17 18:08:45 2017, Dhruva, Update, Optical Levers, Beam Profiling Setup 1.jpg2.jpg3.jpg4.jpg5.jpg
    Reply  Mon May 22 10:53:02 2017, Dhruva, Update, Optical Levers, Beam Profiling Results  6x
       Reply  Tue May 23 10:27:24 2017, Dhruva, Update, Optical Levers, Beam Profiling Results  6x
          Reply  Tue May 23 15:22:04 2017, rana, Update, Optical Levers, Beam Profiling Results  
             Reply  Tue May 30 18:31:54 2017, Dhruva, Update, Optical Levers, Beam Profiling Results  plots.pdfspot_size_y.pdf
                Reply  Thu Jun 8 12:43:42 2017, Dhruva, Update, Optical Levers, Beam Profiling Results  profile.pdf
          Reply  Tue May 23 16:33:00 2017, Steve, Update, Optical Levers, Beam Profiling Results  
Message ID: 13006     Entry time: Tue May 23 10:27:24 2017     In reply to: 13002     Reply to this: 13007   13008
Author: Dhruva 
Type: Update 
Category: Optical Levers 
Subject: Beam Profiling Results  

I have attempted to calculate the instrument error (micrometer least count) using the values of the spot size obtained by the least squares fitting method. This error is large towards the centre of the beam as the power varies significantly between adjecent markings of the micrometer. Using the new values of error obtained, I used the chi-square fitting minimisation method to further optimise the waist size. 

The modified values are - 

z(cm)    w (in)

4         0.0134

10        0.0135

15        0.0140

20        0.0142

25        0.0150

 

And the revised values for the beam waist and location are 338.63 microns and -2.65 cm respectively. 

I will now try to use the chi-square stastitic to estimate the error in spot size. 

Attachment 1: z_25_chisq.pdf  8 kB  | Hide | Hide all
z_25_chisq.pdf
Attachment 2: z_20_chisq.pdf  25 kB  | Hide | Hide all
z_20_chisq.pdf
Attachment 3: z_15_chisq.pdf  7 kB  | Hide | Hide all
z_15_chisq.pdf
Attachment 4: z_10_chisq.pdf  7 kB  | Hide | Hide all
z_10_chisq.pdf
Attachment 5: z_4_chisq.pdf  7 kB  | Hide | Hide all
z_4_chisq.pdf
Attachment 6: spotsize.pdf  8 kB  | Hide | Hide all
spotsize.pdf
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