IMAGE CORRECTING DEVICE, PATTERN INSPECTING DEVICE AND IMAGE CORRECTING METHOD

PURPOSE: To provide a device capable of correcting an image in such a way that the fluctuation of a noise level does not occur according to changes in a shift amount.CONSTITUTION: An image correcting device according to an aspect of the present invention includes: a storing device 50 that stores images; an optimization processing unit 64 that determines a shift amount in the unit of a sub-pixel for either one of the entire image of the image or the partial image of the image for each position; and a sub-pixel interpolation processing unit 60 that performs an interpolation process on either one of the entire image or the partial image for each position according to the shift amount by use of the gradation value of the objective pixel and the gradation value of the peripheral pixel of the objective pixel for each pixel. The interpolation process calculates a linear sum of the gradation value of the objective pixel and the gradation value of the peripheral pixel as the interpolation value of the objective pixel by use of a weighting coefficient of each item set in such a way that the sum of the weighting coefficients of the respective items of the linear sum at the position of the pixel becomes 1, and the square sum of the weighting coefficient of each item becomes a constant which does not depend on the shift amount.SELECTED DRAWING: Figure 5 【目的】シフト量に応じたノイズレベルの変動分が生じないように画像を補正可能な装置を提供する。【構成】本発明の一態様の画像補正装置は、画像を記憶する記憶装置５０と、画像の全体画像と画像の位置毎の部分画像との一方に対して、サブ画素単位のシフト量を決定する最適化処理部６４と、全体画像と位置毎の部分画像との前記一方に対して、画素毎に対象画素の階調値と対象画素の周辺画素の階調値とを用いてシフト量に応じた補間処理を行うサブ画素補間処理部６０と、を備え、補間処理は、画素の位置における線形和の各項の重み付け係数の和が１となり、各項の重み付け係数の２乗和がシフト量に依存しない定数となるように設定された各項の重み付け係数を用いて、対象画素の補間値として、対象画素の階調値と周辺画素の階調値との線形和を演算することを特徴とする。【選択図】図５