Fiber optic flaw detector and identification system

摘要

A fiber optic flaw detection system and method for detecting flaws in an optical fiber and for identifying the type of flaw as a lump, neckdown or other is provided. Three collimated beams of light rays illuminate the optical fiber substantially orthogonal to a longitudinal axis thereof. Each beam is scattered by a flaw-free optical fiber into an in-plane scattered light segment which is scattered in a radial plane substantially perpendicular to the longitudinal axis of the optical fiber. A flaw in the optical fiber scatters the light rays into an out-of-plane scattered light segment which is outside of the radial plane. A pair of photocells detects the out-of-plane scattered light segment for each of the beams. One photocell detects the portion of the out-of-plane light segment scattered opposite the direction of travel of the optical fiber. The other photocell detects the portion of the out-of-plane scattered light segment scattered toward the direction of travel of the optical fiber. Based on the temporal order of the illumination of the respective photocells, the type of flaw in the optical fiber is determined. The size of the flaw is also determined based on the level of illumination each photocell experiences.