Patent · US Expired

Apparatus for detecting a fault location in an optical fiber line

US6185020A · kind A · utility

22Cited by
7References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 4, 1997
Grant dateFeb 6, 2001
Priority date
Expiry dateAug 4, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B10/071
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Disposing optical fiber gratings 10a each reflecting a wavelength .lambda.1 which is different from a signal wavelength .lambda.s along an optical fiber line 10 at suitable intervals and positions. The wavelength .lambda.s of signal light is not reflected by the grating 10a, but transmitted through the optical fiber line 10. An optical pulse tester 14 outputs probe pulse lights of wavelengths .lambda.0, .lambda.1, which are different from the signal wavelength .lambda.s, at slightly different times. The probe lights of the wavelengths .lambda.0, .lambda.1 are input into the optical fiber line 10 through an optical adding and dividing device 16 and transmitted through the optical fiber line 10. Reflected light of the wavelength .lambda.1 of probe light contains therein reflection pulses of the grating 10a, and each reflection pulse serves as a position reference. The probe light of the wavelength .lambda.0 does not contain reflection light of the grating 10a. Comparison of the reflected lights of the wavelengths .lambda.0, .lambda.1 to each other by the optical pulse tester 14, provides determination of whether there is a fault location, and, if so, detection of fault location with …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.