The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 29, 2003
Filed:
Aug. 15, 2001
The Furukawa Electric Co., Ltd., Tokyo, JP;
Abstract
In defect detecting method for detecting defect of an optical fiber to be measured, in which a laser beam is illuminated onto an optical fiber to be measured from a direction transverse to an optical axis of the fiber to check intensity distribution of forward scattering light permeated through within the optical fiber and scattered, and the defect of the optical fiber to be measured is detected on the basis of a pattern of the intensity distribution, the pattern of the intensity distribution is subjected to a smoothing process having weak smoothness and a smoothing process having strong smoothness to form first and second patterns, respectively, and a judging pattern is formed on the basis of a difference or the quotient between the first and second patterns, and the defect of the optical fiber to be measured is detected by evaluating magnitude of the judging pattern. The pattern of the intensity distribution is subjected to Fourier transform to form a frequency spectrum pattern, and the frequency spectrum pattern is evaluated by using double logarithmic axis, and a judging curve having high contributing rate to the frequency spectrum pattern is applied to the frequency spectrum pattern to seek dispersion of the frequency spectrum pattern from the judging curve, and the defect of the optical fiber to be measured is detected on the basis of magnitude of the dispersion.