skip to main content
DOE Patents title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Method and apparatus for determining peak temperature along an optical fiber

Abstract

The invention relates to a new method and new apparatus for determining the hottest temperature or the coldest temperature prevailing along the length of an optical-fiber light guide. The invention is conducted with an optical fiber capable of supporting multidiode propagation of light and comprising a core, a cladding, and a jacket. The core is selected to have (1) a higher refractive index than the core and the cladding and (2) a relatively high negative temperature coefficient of refractive index. A light beam capable of establishing substantially single-mode propagation in the core is launched into an end thereof at an angle to the axis. The angle is increased to effect the onset of light refraction from the core into the cladding. The value of the launch angle corresponding to the onset is determined and then used to establish the refractive index of the core corresponding to the onset angle. The maximum temperature prevailing along the fiber then is determined from the (1) refractive index so determined and (2) the temperature coefficient of refractive index for the core. The invention is based on the finding that the launch angle corresponding to the onset of refraction into the cladding is uniquely determinedmore » by the maximum value of the ratio of the core refractive index to the cladding refractive index, which maximum occurs at the hottest point along the fiber.« less

Inventors:
 [1]
  1. (Oak Ridge, TN)
Issue Date:
Research Org.:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN
OSTI Identifier:
865442
Patent Number(s):
4515474
Assignee:
United States of America as represented by United States (Washington, DC) ORNL
DOE Contract Number:  
W-7405-ENG-26
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
method; apparatus; determining; peak; temperature; optical; fiber; relates; hottest; coldest; prevailing; length; optical-fiber; light; guide; conducted; capable; supporting; multidiode; propagation; comprising; core; cladding; jacket; selected; refractive; index; relatively; negative; coefficient; beam; establishing; substantially; single-mode; launched; angle; axis; increased; effect; onset; refraction; value; launch; corresponding; determined; establish; maximum; based; finding; uniquely; ratio; occurs; temperature coefficient; optical fiber; light beam; refractive index; light guide; fiber light; maximum temperature; maximum value; substantially single; /356/374/

Citation Formats

Fox, Richard J. Method and apparatus for determining peak temperature along an optical fiber. United States: N. p., 1985. Web.
Fox, Richard J. Method and apparatus for determining peak temperature along an optical fiber. United States.
Fox, Richard J. Tue . "Method and apparatus for determining peak temperature along an optical fiber". United States. https://www.osti.gov/servlets/purl/865442.
@article{osti_865442,
title = {Method and apparatus for determining peak temperature along an optical fiber},
author = {Fox, Richard J.},
abstractNote = {The invention relates to a new method and new apparatus for determining the hottest temperature or the coldest temperature prevailing along the length of an optical-fiber light guide. The invention is conducted with an optical fiber capable of supporting multidiode propagation of light and comprising a core, a cladding, and a jacket. The core is selected to have (1) a higher refractive index than the core and the cladding and (2) a relatively high negative temperature coefficient of refractive index. A light beam capable of establishing substantially single-mode propagation in the core is launched into an end thereof at an angle to the axis. The angle is increased to effect the onset of light refraction from the core into the cladding. The value of the launch angle corresponding to the onset is determined and then used to establish the refractive index of the core corresponding to the onset angle. The maximum temperature prevailing along the fiber then is determined from the (1) refractive index so determined and (2) the temperature coefficient of refractive index for the core. The invention is based on the finding that the launch angle corresponding to the onset of refraction into the cladding is uniquely determined by the maximum value of the ratio of the core refractive index to the cladding refractive index, which maximum occurs at the hottest point along the fiber.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1985},
month = {1}
}

Patent:

Save / Share: