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Message ID: 144     Entry time: Sat Jun 27 22:09:36 2009
Author: Dmass 
Type: Laser 
Category: PSL 
Subject: I did some things in lab, some of which were bad. 

I fired up the 35W, and everything was still working as per my last entry - we still could lock the PMC, and were generating small amounts of green.

  • I replaced the old home made mode matching lens slider mounts with real slider mounts
  • I then realized that I had no transverse adjustment with these sliders, which ended up being a royal PITA for alignment
  • I went back to the old mounts and tried to restore their position very faithfully, but had not documented their placement
  • I am now not aligned well into the PMC, and can't find the 00 - some combination of lens position adjustment and angular alignment should fix this.


I took a series of beam scans to find the waist size/position of the beam coming into the PMC and noticed a few things:

  • The beam scan IS UNHAPPY <edit with specific error> when it boots up the software
  • This *seems* to be making a number of features unavailable (i.e. the position dot, the contour plots, dual axis display...)
  • All of the things that I was unable to get to work involved needing both axes of the beamscan to work.
  • It seems like there is at least one ghost beam which is ~ on axis. I am unsure as to whether this is modal content of the PSL or a ghost from some optic.
  • The horizontal axis was FUGLY in modal content; the near vertical was pretty, and resembled a guassian. <Pics to be attached>


  • Troubleshoot: Look at the beamscan documentation regarding its startup errors/running the features that were "greyed out"
  • Enter data into mode matching program - get desired adjustments to lens positions
  • Verify orientation of lenses (both are plano convex, and I currently have the curved surfaces pointed towards each other)
  • Once I get a lock to the 00 mode, do fine tune of mode matching and angular alignment by hand
  • Move on to making my SHG more efficient, and maybe move up to tens of uW


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