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Entry  Wed Nov 18 17:49:05 2020, Paco, DailyProgress, Optics, beam profiles 2020_11_18_ecdlprofile.png2020_11_18_mephistoprofile.png
    Reply  Mon Dec 21 16:35:14 2020, Anchal, DailyProgress, Optics, Took beam profile of laser right off the head LaserHeadBeamProfileAvg.pdfLaserHeadBeamProfileX.pdfLaserHeadBeamProfileY.pdf
       Reply  Tue Dec 22 15:54:03 2020, Anchal, DailyProgress, Optics, Took beam profile of near EOM area BeamProfileNearEOMAvg.pdf
          Reply  Mon Dec 28 15:51:51 2020, Anchal, DailyProgress, Optics, Mode matching solution for Cavity Solutions1-7merged.pdf
             Reply  Thu Dec 31 16:41:59 2020, Anchal, DailyProgress, Optics, Mode matching solution for Cavity Solutions.pdf
                Reply  Wed Jan 6 09:34:34 2021, Anchal, DailyProgress, Optics, Corrected analysis and found better solutions. Solutions.pdf
                   Reply  Fri Jan 8 17:00:26 2021, Anchal, DailyProgress, Optics, Included lens made by cavity input mirror and distrotion due to crystal Solutions.pdf
                   Reply  Fri Jan 8 17:17:19 2021, Anchal, DailyProgress, Optics, Included lens made by cavity input mirror and distrotion due to crystal Solutions.pdf
                      Reply  Tue Jan 26 11:33:32 2021, rana, DailyProgress, Optics, Included lens made by cavity input mirror and distrotion due to crystal 
                      Reply  Tue Jan 26 11:34:51 2021, rana, DailyProgress, Optics, Included lens made by cavity input mirror and distrotion due to crystal 
Message ID: 1887     Entry time: Wed Jan 6 09:34:34 2021     In reply to: 1886     Reply to this: 1890   1891
Author: Anchal 
Type: DailyProgress 
Category: Optics 
Subject: Corrected analysis and found better solutions. 

Errors in the previous analysis

  • Previously, we wrongly assumed. that the reflected light from the cavity would be as if a reflection is happening from a flat mirror. It actually follows the same paths as incident light in the reflection path.
  • Lens were restricted to non-overlapping regions but that meant that solutions where lens are close to each other can only happen near the boundaries of these regions. Removing this condition widens the search for a good solution.
  • We collimated the beam to near 0.5 mm radius with a 229.1 mm focal length lens at 67" from laser head and put faraday isolator in front. So now the problem only remained to match the mode after this point to the cavity mode.

Goals and restrictions:

  • Use the fewest lenses as possible after having used a fixed lens at 67" point before the faraday isolator.
  • Choose a lens from a list of focal lengths available in west bridge labs.
  • Find the best overlap with the target beam of 18 um at the cavity waist with the most sensitivity with respect to lens positions.
  • The lens should not be closer than 1.5 inches from each other or to the EOM mount or cavity edge.
  • The beam widths should not exceed 4mm in diameter anywhere to ensure small areas of lenses are used.

Analysis & Results


Analysis & Data

Attachment 1: Solutions.pdf  327 kB  | Show | Show all
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