Printed circuit board defect detection of detecting maximum line

Optics: measuring and testing – Inspection of flaws or impurities – Having predetermined light transmission regions

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356394, 356398, 382 8, G06K 900

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active

045002029

ABSTRACT:
An automatic printed wiring (or circuit) board (PWB) method for detecting maximum line width violations is described. The method utilizes an array of optical sensors for optically inspecting a printed wire circuit. The array forms a binary image pattern of the PWB which is tested for compliance with logical rules of correctly printed PWB's regarding maximum line width. The detector comprises a plurality of CCD arrays arranged to form a series of pixels consisting of electronic binary signals corresponding to the instantaneous image viewed by each element in the CCD array. These pixels are formed in an image data stream of sequential pixels line-by-line of the CCD array, i.e., pixel sequential line sequential digital image data. The digital pixel data is formatted in an "N" by "N" bit matrix of points in proper image orientation. All such points are available for sampling. Each pixel progressively occupies each point in the matrix in proper orientation to its neighbors. Each pixel passes through each "N" bit point of the matrix thus forming a moving "window" of "N" by "N" bits in size of a portion of the image viewed by the CCD array. The contents of the matrix are addressed and selected and logic applied thereto to determine compliance with localized PWB principles.

REFERENCES:
patent: 3389789 (1968-06-01), Watson et al.
patent: 3665326 (1972-05-01), Sullivan
patent: 3969577 (1976-07-01), Lloyd et al.
patent: 3987244 (1976-10-01), Messman
patent: 4083035 (1978-04-01), Riganati et al.
patent: 4152723 (1979-05-01), McMahon et al.
patent: 4185298 (1980-01-01), Billet et al.
patent: 4240750 (1980-12-01), Kurtz et al.
patent: 4251837 (1981-02-01), Janeway
patent: 4259662 (1981-03-01), Yoshida
patent: 4269515 (1981-05-01), Altman
patent: 4295120 (1981-10-01), Yoshida
patent: 4295198 (1981-10-01), Copeland et al.
patent: 4300122 (1981-11-01), McMahon
patent: 4301471 (1981-11-01), Holscher et al.
patent: 4345314 (1982-08-01), Melamud et al.
patent: 4392120 (1983-07-01), Mita et al.
patent: 4403294 (1983-09-01), Hamada et al.
"The Inspectron: An Automatic Optical Printed Circuit Board (PCB) Inspector" by William A. Bentley, SPIE, vol. 201, Optical Pattern Recognition (1979), pp. 37-47.
"An Automatic Optical Printed Circuit Inspection System" by Robert C. Restrick, III, SPIE, vol. 116 Solid State Imaging Devices (1977).
"Distance Checking Algorithms" by Per-Erik Danielsson & Bjorn Kruse, Linkoping University, Dept. of Electrical Engineering, 09-21-1977.
"An Automatic Inspection System for Printed Wiring Board Masks" by Goto et al., Pattern Recognition, vol. 12, pp. 443-455, Pergamon Press Ltd. 1980.
"Automated Optical Inspection of Multilayer Printed Circuit Boards" by William A. Bentley, SPIE, vol. 220, Optics in Metrology and Quality Assurance (1980).

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