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Title: High power, high beam quality regenerative amplifier

Abstract

A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct themore » beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.« less

Inventors:
;
Issue Date:
OSTI Identifier:
6038291
Patent Number(s):
5239408 A
Application Number:
PPN: US 7-948488
Assignee:
Univ. of California, Oakland, CA (United States)
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Patent
Resource Relation:
Patent File Date: 22 Sep 1992
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; LASERS; DESIGN; AMPLIFICATION; GAIN; LASER MIRRORS; LASER RADIATION; PHASE SHIFT; POLARIZATION; REGENERATION; ELECTROMAGNETIC RADIATION; MIRRORS; RADIATIONS; 426002* - Engineering- Lasers & Masers- (1990-)

Citation Formats

Hackel, L A, and Dane, C B. High power, high beam quality regenerative amplifier. United States: N. p., 1993. Web.
Hackel, L A, & Dane, C B. High power, high beam quality regenerative amplifier. United States.
Hackel, L A, and Dane, C B. Tue . "High power, high beam quality regenerative amplifier". United States.
@article{osti_6038291,
title = {High power, high beam quality regenerative amplifier},
author = {Hackel, L A and Dane, C B},
abstractNote = {A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1993},
month = {8}
}