POSITION MEASUREMENT INSTRUMENT AND POSITION MEASUREMENT METHOD

• Main Author: TANIGUCHI KAZUTAKA
• Format: Patent
• Language: English; Japanese
• Published: 05.04.2018
• Subjects: APPARATUS SPECIALLY ADAPTED THEREFOR; CALCULATING; CINEMATOGRAPHY; COMPUTING; COUNTING; ELECTROGRAPHY; HOLOGRAPHY; IMAGE DATA PROCESSING OR GENERATION, IN GENERAL; MATERIALS THEREFOR; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; ORIGINALS THEREFOR; PHOTOGRAPHY; PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES,e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTORDEVICES; PHYSICS; TESTING

PROBLEM TO BE SOLVED: To accurately measure center coordinates of a rectangular-shaped figure included in a two-dimensional original image obtained by imaging an object.SOLUTION: A position measurement instrument for measuring center coordinates of a rectangular-shaped figure included in a two-dimensional original image obtained by imaging an object comprises: an image storage unit for storing an original image obtained by imaging an object; and a computation unit for modeling pixel value distribution of the figure in the original image with use of a partial-differentiable model function and determining a plurality of coefficients included in the model function by the optimization method to find center coordinates of the figure. The plurality of coefficients include a specific coefficient which shows a change of pixel value distribution, from Gauss distribution to top hat type distribution, and a change of an equal pixel value plane formed of pixels having the same pixel value, from circular shape to rectangular shape.SELECTED DRAWING: Figure 3 【課題】対象物を撮像した二次元の原画像に含まれる矩形形状の図形の中心座標を高精度に計測する。【解決手段】対象物を撮像した二次元の原画像に含まれる矩形形状の図形の中心座標を計測する位置計測装置であって、対象物を撮像した原画像を記憶する画像記憶部と、原画像における図形の画素値分布を、偏微分可能なモデル関数にてモデル化し、モデル関数に含まれる複数の係数を最適化法にて決定することにより図形の中心座標を求める演算部と、を備え、複数の係数は、画素値分布のガウス分布からトップハット型分布への推移ならびに同一画素値を有する画素で形成される等画素値面の円形から矩形への推移を表す特定係数を含んでいる。【選択図】図３