METHOD OF MEASURING DIAMETER AND SLIT WIDTH OF LINEAR BODY

摘要

Provided is a method for measuring the diameter of a linear body on the basis of a light diffraction pattern of a laser beam which is projected upon the linear body. The method comprises: a first step of projecting a laser beam toward a light receiving unit in a state wherein a linear body is not positioned in a measuring unit, and acquiring a first light intensity distribution with the light receiving unit; a second step of projecting the laser beam toward the light receiving unit in a state wherein the linear body is positioned in the measuring unit, and acquiring a second light intensity distribution with the light receiving unit; a step of subtracting the second light intensity distribution which is acquired with the second step from the first light intensity distribution which is acquired with the first step, and acquiring a light diffraction pattern; and a step of computing the diameter of the linear body on the basis of a primary light peak gap which is obtained from the acquired light diffraction pattern.