40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  PSL  Not logged in ELOG logo
Entry  Sun Mar 10 14:23:56 2013, Evan, Notes, Drawings, Mode matching plan for beat breadboard beat_modematch_layout.pdfbeat_modematch_alm.pdf
    Reply  Tue Mar 12 20:51:00 2013, rana, Notes, BEAT, Mode matching plan for beat breadboard 
Message ID: 1113     Entry time: Sun Mar 10 14:23:56 2013     Reply to this: 1115
Author: Evan 
Type: Notes 
Category: Drawings 
Subject: Mode matching plan for beat breadboard 

I ran CVI's list of 1064-nm silica lenses through a la mode looking for a good way to get the cavity beams onto the beat PD. We're looking for a spot with radius somewhere between 80 and 150 um at the PD.

I tried a few optimizations with only one lens in each beam's path, but the results weren't very good; the beam is either too large, too small, or requires excessive path length after the BS. What I've attached is the result of an optimization for two lenses in each beam's path. It gives a 102 um waist a few inches after the last folding mirror, which is nice. The spot radius at the BS is 470 um, which is not too large.

Attachment 1: beat_modematch_layout.pdf  17 kB  | Hide | Hide all
beat_modematch_layout.pdf
Attachment 2: beat_modematch_alm.pdf  91 kB  | Hide | Hide all
beat_modematch_alm.pdf
ELOG V3.1.3-