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Title: Growing Crystaline Sapphire Fibers By Laser Heated Pedestal Techiques

Abstract

An improved system and process for growing crystal fibers comprising a means for creating a laser beam having a substantially constant intensity profile through its cross sectional area, means for directing the laser beam at a portion of solid feed material located within a fiber growth chamber to form molten feed material, means to support a seed fiber above the molten feed material, means to translate the seed fiber towards and away from the molten feed material so that the seed fiber can make contact with the molten feed material, fuse to the molten feed material and then be withdrawn away from the molten feed material whereby the molten feed material is drawn off in the form of a crystal fiber. The means for creating a laser beam having a substantially constant intensity profile through its cross sectional area includes transforming a previously generated laser beam having a conventional gaussian intensity profile through its cross sectional area into a laser beam having a substantially constant intensity profile through its cross sectional area by passing the previously generated laser beam through a graded reflectivity mirror. The means for directing the laser beam at a portion of solid feed material is configuredmore » to direct the laser beam at a target zone which contains the molten feed material and a portion of crystal fiber drawn off the molten feed material by the seed fiber. The means to support the seed fiber above the molten feed material is positioned at a predetermined height above the molten feed material. This predetermined height provides the seed fiber with sufficient length and sufficient resiliency so that surface tension in the molten feed material can move the seed fiber to the center of the molten feed material irrespective of where the seed fiber makes contact with the molten feed material. The internal atmosphere of the fiber growth chamber is composed substantially of Helium gas.

Inventors:
 [1];  [2];  [2]
  1. St. Petersburg, FL
  2. Tampa, FL
Issue Date:
Research Org.:
Univ. of South Florida, Tampa, FL (United States)
OSTI Identifier:
879239
Patent Number(s):
5607506
Application Number:
08/327454
Assignee:
University of South Florida (Tampa, FL)
Patent Classifications (CPCs):
C - CHEMISTRY C30 - CRYSTAL GROWTH C30B - SINGLE-CRYSTAL-GROWTH
Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
DOE Contract Number:  
FC04-95AL85816
Resource Type:
Patent
Country of Publication:
United States
Language:
English

Citation Formats

Phomsakha, Vongvilay, Chang, Robert S. F., and Djeu, Nicholas I. Growing Crystaline Sapphire Fibers By Laser Heated Pedestal Techiques. United States: N. p., 1997. Web.
Phomsakha, Vongvilay, Chang, Robert S. F., & Djeu, Nicholas I. Growing Crystaline Sapphire Fibers By Laser Heated Pedestal Techiques. United States.
Phomsakha, Vongvilay, Chang, Robert S. F., and Djeu, Nicholas I. Tue . "Growing Crystaline Sapphire Fibers By Laser Heated Pedestal Techiques". United States. https://www.osti.gov/servlets/purl/879239.
@article{osti_879239,
title = {Growing Crystaline Sapphire Fibers By Laser Heated Pedestal Techiques},
author = {Phomsakha, Vongvilay and Chang, Robert S. F. and Djeu, Nicholas I},
abstractNote = {An improved system and process for growing crystal fibers comprising a means for creating a laser beam having a substantially constant intensity profile through its cross sectional area, means for directing the laser beam at a portion of solid feed material located within a fiber growth chamber to form molten feed material, means to support a seed fiber above the molten feed material, means to translate the seed fiber towards and away from the molten feed material so that the seed fiber can make contact with the molten feed material, fuse to the molten feed material and then be withdrawn away from the molten feed material whereby the molten feed material is drawn off in the form of a crystal fiber. The means for creating a laser beam having a substantially constant intensity profile through its cross sectional area includes transforming a previously generated laser beam having a conventional gaussian intensity profile through its cross sectional area into a laser beam having a substantially constant intensity profile through its cross sectional area by passing the previously generated laser beam through a graded reflectivity mirror. The means for directing the laser beam at a portion of solid feed material is configured to direct the laser beam at a target zone which contains the molten feed material and a portion of crystal fiber drawn off the molten feed material by the seed fiber. The means to support the seed fiber above the molten feed material is positioned at a predetermined height above the molten feed material. This predetermined height provides the seed fiber with sufficient length and sufficient resiliency so that surface tension in the molten feed material can move the seed fiber to the center of the molten feed material irrespective of where the seed fiber makes contact with the molten feed material. The internal atmosphere of the fiber growth chamber is composed substantially of Helium gas.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1997},
month = {3}
}

Works referenced in this record:

Graded reflectance mirrors and phase-unifying mirrors for XeCl lasers
journal, July 1994


Characterization of single‐crystal sapphire fibers for optical power delivery systems
journal, November 1989


Crystal growth of sapphire filaments by a laser-heated floating zone technique
journal, March 1977


Low-Loss Single-Crystal Sapphire Optical Fibers
conference, May 1986