Patent ID: 6600554
Filing Date: 2003-07-29
Classification: G01M

Abstract:
A defect detecting method for detecting defect of an optical fiber, in which a laser beam is illuminated onto the optical fiber to be measured from a direction transverse to an optical axis of said optical fiber to check intensity distribution of forward scattering light permeated through said optical fiber and scattered, and the defect of said optical fiber to be measured is detected on the basis of a pattern of the intensity distribution, comprising:subjecting said pattern of the intensity distribution to a smoothing process having weak smoothness and a smoothing process having strong smoothness to form first and second patterns, respectively; forming a judging pattern on the basis of a difference between said first and second patterns; forming a change threshold pattern associated with said first and second patterns; and detecting the defect of said optical fiber to be measured by comparing said change threshold pattern with said judging pattern.