Defect information processing apparatus and method
AssigneeCanon Kabushiki Kaisha
InventorMasaharu Okabe
Life of this patent
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Abstract
A two-dimensional image of an object to be inspected is captured, and is converted into multi-valued digital data by an A/D converter (2). A vertical filter (4) computes difference values of the multi-valued digital image data in units of pixels within a predetermined range in the vertical direction, and a horizontal filter (5) computes difference values in the horizontal direction based on the difference values computed by the vertical filter (4). A binary converter (7) converts the difference values computed by the horizontal filter (5) into binary data on the basis of a predetermined reference value. A defect portion of the object to be inspected is detected based on the multi-valued digital data as the difference values computed by the horizontal filter (5), and binary data.
Claims24
A defect information processing apparatus comprising:
- image input means for capturing a two-dimensional image of an object to be inspected;
- digital conversion means for converting the two-dimensional image into multi-valued digital image data;
- vertical filter means for filtering the multi-valued digital image data in a vertical direction;
- horizontal filter means for filtering the multi-valued digital image data, which has been filtered by said vertical filter means, in a horizontal direction;
- binarization means for converting the multi-valued digital image data, which has been filtered by said horizontal filter means, into binary data on the basis of a predetermined reference value;
- and
- detection means for detecting a defect portion of the object to be inspected on the basis of the multi-valued digital image data and binary data,
- wherein said vertical filter means comprises vertical difference computation means for computing a difference value of the multi-valued digital image data within a predetermined range in the vertical direction, and vertical weighting means for weighting the difference value computed by said vertical difference computation means, and
- said horizontal filter means comprises horizontal difference computation means for computing a difference value of the multi-valued digital image data within a predetermined range in the horizontal direction, and horizontal weighting means for weighting the difference value computed by said horizontal difference computation means.
A defect information processing method comprising:
- the image input step of capturing a two-dimensional image of an object to be inspected;
- the digital conversion step of converting the two-dimensional image into multi-valued digital image data;
- the vertical filter step of filtering the multi-valued digital image data in a vertical direction;
- the horizontal filter step of filtering the multi-valued digital image data, which has been filtered in the vertical filter step, in a horizontal direction;
- the binarization step of converting the multi-valued digital image data, which has been filtered in the horizontal filter step, into binary data on the basis of a predetermined reference value;
- and
- the detection step of detecting a defect portion of the object to be inspected on the basis of the multi-valued digital image data and binary data,
- wherein the vertical filter step comprises the vertical difference computation step of computing a difference value of the multi-valued digital image data within a predetermined range in the vertical direction, and the vertical weighting step of weighting the difference value computed in the vertical difference computation step, and
- the horizontal filter step comprises the horizontal difference computation step of computing a difference value of the multi-valued digital image data within a predetermined range in the horizontal direction, and the horizontal weighting step of weighting the difference value computed in the horizontal difference computation step.
A computer readable memory that stores a program code which comprises codes of the image input step of capturing a two-dimensional image of an object to be inspected, the digital conversion step of converting the two-dimensional image into multi-valued digital image data, the vertical difference computation step of computing a difference value of the multi-valued digital image data within a predetermined range in the vertical direction, the vertical weighting step of weighting the difference value computed in the vertical difference computation step, the horizontal difference computation step of computing a difference value of the multi-valued digital image data within a predetermined range in the horizontal direction, the horizontal weighting step of weighting the difference value computed in the horizontal difference computation step, and the detection step of detecting a defect portion of the object to be inspected on the basis of the multi-valued digital image data and binary data, which is generated via the binarization step of converting the multi-valued digital image data, which has been computed via the horizontal weighting step, into binary data on the basis of a predetermined reference value, and processes defect information of the object to be inspected, comprising:
- a code of the step of computing feature data of a pixel which corresponds to the binary data=1;
- and
- a code of determining based on the feature data if the object to be inspected is good.
Dependencies are inferred from the claim text.