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Title: Method and apparatus for timing of laser beams in a multiple laser beam fusion system

Abstract

The optical path lengths of a plurality of comparison laser beams directed to impinge upon a common target from different directions are compared to that of a master laser beam by using an optical heterodyne interferometric detection technique. The technique consists of frequency shifting the master laser beam and combining the master beam with a first one of the comparison laser beams to produce a time-varying heterodyne interference pattern which is detected by a photo-detector to produce an AC electrical signal indicative of the difference in the optical path lengths of the two beams which were combined. The optical path length of this first comparison laser beam is adjusted to compensate for the detected difference in the optical path lengths of the two beams. The optical path lengths of all of the comparison laser beams are made equal to the optical path length of the master laser beam by repeating the optical path length adjustment process for each of the comparison laser beams. In this manner, the comparison laser beams are synchronized or timed to arrive at the target within .+-.1.times.10.sup.-12 second of each other.

Inventors:
 [1];  [2]
  1. Pittsford, NY
  2. Rochester, NY
Issue Date:
Research Org.:
University of Rochester, Laboratory for Laser Energetics, Rochester, New York
OSTI Identifier:
863903
Patent Number(s):
4272193
Assignee:
United States of America as represented by United States (Washington, DC)
Patent Classifications (CPCs):
G - PHYSICS G01 - MEASURING G01J - MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRA-RED, VISIBLE OR ULTRA-VIOLET LIGHT
G - PHYSICS G21 - NUCLEAR PHYSICS G21B - FUSION REACTORS
DOE Contract Number:  
EY-76-C-02-2812
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
method; apparatus; timing; laser; beams; multiple; beam; fusion; optical; path; lengths; plurality; comparison; directed; impinge; common; target; directions; compared; master; heterodyne; interferometric; detection; technique; consists; frequency; shifting; combining; produce; time-varying; interference; pattern; detected; photo-detector; electrical; signal; indicative; difference; combined; length; adjusted; compensate; equal; repeating; adjustment; process; manner; synchronized; timed; arrive; times; 10; -12; path lengths; frequency shift; master laser; interference pattern; path length; laser beams; electrical signal; laser beam; optical path; signal indicative; optical heterodyne; multiple laser; interferometric detection; common target; /356/376/

Citation Formats

Eastman, Jay M, and Miller, Theodore L. Method and apparatus for timing of laser beams in a multiple laser beam fusion system. United States: N. p., 1981. Web.
Eastman, Jay M, & Miller, Theodore L. Method and apparatus for timing of laser beams in a multiple laser beam fusion system. United States.
Eastman, Jay M, and Miller, Theodore L. Thu . "Method and apparatus for timing of laser beams in a multiple laser beam fusion system". United States. https://www.osti.gov/servlets/purl/863903.
@article{osti_863903,
title = {Method and apparatus for timing of laser beams in a multiple laser beam fusion system},
author = {Eastman, Jay M and Miller, Theodore L},
abstractNote = {The optical path lengths of a plurality of comparison laser beams directed to impinge upon a common target from different directions are compared to that of a master laser beam by using an optical heterodyne interferometric detection technique. The technique consists of frequency shifting the master laser beam and combining the master beam with a first one of the comparison laser beams to produce a time-varying heterodyne interference pattern which is detected by a photo-detector to produce an AC electrical signal indicative of the difference in the optical path lengths of the two beams which were combined. The optical path length of this first comparison laser beam is adjusted to compensate for the detected difference in the optical path lengths of the two beams. The optical path lengths of all of the comparison laser beams are made equal to the optical path length of the master laser beam by repeating the optical path length adjustment process for each of the comparison laser beams. In this manner, the comparison laser beams are synchronized or timed to arrive at the target within .+-.1.times.10.sup.-12 second of each other.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 1981},
month = {Thu Jan 01 00:00:00 EST 1981}
}