UNEVENNESS INSPECTION METHOD AND SYSTEM OF PERIODICAL PATTERN

• Main Authors: OKAZAWA ATSUSHI, SOEDA MASAHIKO
• Format: Patent
• Language: English
• Published: 22.04.2004
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS; ELECTRICITY; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; PHYSICS; TESTING; TESTING STATIC OR DYNAMIC BALANCE OF MACHINES ORSTRUCTURES; TESTING STRUCTURES OR APPARATUS NOT OTHERWISE PROVIDED FOR

PROBLEM TO BE SOLVED: To accurately inspect periodical patterns without being influenced by moire fringes by inputting the just focused image of an object. SOLUTION: When the object W with narrow patterns repeatedly formed in the widthwise direction is inspected, the pixel line direction of a line sensor camera 12 is squared with the formation direction of the patterns; the proper focus is set; each pattern in an imaging range is set in a visual field of one pixel over the total width; the object image is imaged by setting a scan rate causing an aspect ratio to exceed one in an optical condition where a luminance value in the case that two patterns are partially included in the visual field of one pixel is not equal to that in the case that only one of the patterns is included; a transmittance image is formed by dividing the image by a light source image imaged by excluding the object; a pattern image of a pixel corresponding to the luminance value of the total width of the each pattern is created from the image; and the pattern is inspected based on the image. COPYRIGHT: (C)2004,JPO