Method and apparatus for detecting defects of printed circuit patterns

Claim 1

A method of detecting a defect of a circuit pattern comprising the steps of: (a) converting an optical image of a circuit pattern into electrical image signals by using an image pickup means; (b) transforming said electrical image signals into binary signals of picture elements by using a binary unit; (c) providing a pad of said pattern represented by said binary signals of picture elements with a symbol forming an object pad number corresponding to an address of said pad when said pad is detected at the position of said address designated by a pad position memory; (d) examining the connectivity between pads thus provided with a symbol forming said object pad number by using a connectivity processor, thereby to provide a pad with a symbol forming a mother pad number representative of the same group to which said pad belongs if said pad is connected with the other pad, and to provide a pad with a symbol forming a mother pad number corresponding to the object pad number of said pad if said pad is not connected with the other pad; (e) generating connection data consisting of said object pad number and said mother pad number to represent connectivity of said pads; (f) storing said connection data into a connection data memory; (g) storing into a design data memory design data consisting of an address of a pad of said pattern and a pad number corresponding to another address of another pad of said pattern if said pad and said another pad are connected with each other; and (h) comparing said connection data with said design data by using a processor to produce attribute data on the basis of which defectiveness of the circuit pattern is determined.

Claim 2

A method of detecting a defect of a circuit pattern comprising the steps of: (a) converting an optical image of a circuit pattern into electrical image signals by using an image pickup means; (b) transforming said electrical image signals into binary signals of picture elements by using a binary unit; (c) providing a pad of said pattern represented by said binary signals of picture elements with a symbol forming an object pad number corresponding to an address of said pad when said pad is detected at the position of said address designated by a pad position memory; (d) examining the connectivity between pads thus provided with a symbol forming said object pad number by using a connectivity processor, thereby to provide a pad with a symbol forming a mother pad number representative of the same group to which said pad belongs if said pad is connected with the other pad, and to provide a pad with a symbol forming a mother pad number corresponding to the object pad number of said pad if said pad is not connected with the other pad; (e) generating connection data consisting of said object pad number and said mother pad number to represent connectivity of said pads; (f) storing said connection data into a connection data memory; (g) storing into a design data memory design data consisting of an address of a pad of said pattern and a pad number corresponding to another address of another pad of said pattern if said pad and said another pad are connected with each other; and (h) comparing said connection data with said design data by using a processor to produce attribute data on the basis of which defectiveness of the circuit pattern is determined.

Claim 12

An apparatus for detecting a defect of a circuit pattern comprising: image pickup means which senses an optical image of a circuit pattern and provides an electrical image signal; a binary digitizing circuit which transforms said electrical image signal into binary signals representing picture elements; connection data generating means which examines the connectivity relationship between two selected points of the circuit pattern represented by said binary and produces connection data signals representative of a connectivity relationship expressed by a pair of symbols given to said points; and comparison means for comparing said connection data signals with design data signals expressed in the form of a circulation list of symbols given to points in connectivity relationship, whereby determination of defectiveness of the pattern is made based on the output of said comparison means.

Claim 13

An apparatus for detecting a defect of a circuit pattern comprising: image pickup means which senses an optical image of a circuit pattern and provides an electrical image signal; a binary digitizing circuit which transforms said electrical image signal into binary signals representing picture elements; connection data generating means which examines the connectivity relationship between two selected points of the circuit pattern represented by said binary and produces connection data signals representative of a connectivity relationship expressed by a pair of symbols given to said points; and comparison means for comparing said connection data signals with design data signals expressed in the form of a circulation list of symbols given to points in connectivity relationship, whereby determination of defectiveness of the pattern is made based on the output of said comparison means.

Claim 16

An apparatus for detecting a defect of a circuit pattern comprising means for illuminating an object and means for transducing an optical image of said illuminated object into an electrical signal so as to detect a defect of a circuit pattern formed on a planar surface of said object, wherein said illumination means is disposed so that said object is illuminated on a side of the formation of said circuit pattern, and wherein said apparatus further comprises two sets of image pickup means which sense the same position of said illuminated pattern along optical axes of different directions on the side of pattern formation and transform luminance images of the circuit pattern into electrical signals, and means for composing pattern sections of said two electrical signals.

Claim 17

An apparatus for detecting a defect of a circuit pattern comprising means for illuminating an object and means for transducing an optical image of said illuminated object into an electrical signal so as to detect a defect of a circuit pattern formed on a planar surface of said object, wherein said illumination means is disposed so that said object is illuminated on a side of the formation of said circuit pattern, and wherein said apparatus further comprises two sets of image pickup means which sense the same position of said illuminated pattern along optical axes of different directions on the side of pattern formation and transform luminance images of the circuit pattern into electrical signals, and means for composing pattern sections of said two electrical signals.

Claim 23

An apparatus for detecting a defect of a circuit pattern comprising: image pickup means which senses an optical image of a circuit pattern and provides an electrical image signal; a binary digitizing circuit which transforms said electrical image signal into binary signals representing picture elements; expansion means connected to said binary digitizing circuit for effecting a expansion process on the pattern represented by said binary signals to produce expanded pattern signals; first connection data generating means connected to said binary digitizing circuit for examining the connectivity relationship between two selected points of the circuit pattern represented by said binary signals and producing first connection data signals representative of a connectivity relationship for said points; second connection data generating means connected to said expansion means for examining the connectivity relationship between said two selected points of the circuit pattern represented by said expansion pattern signals and producing second connection data signals representative of a connectivity relationship for said points; and comparison means for comparing said first and second connection data signals to design data signals for said two selected points for producing an output representing a determination of the defectiveness of the pattern based on said comparison.

Claim 24

An apparatus for detecting a defect of a circuit pattern comprising: image pickup means which senses an optical image of a circuit pattern and provides an electrical image signal; a binary digitizing circuit which transforms said electrical image signal into binary signals representing picture elements; expansion means connected to said binary digitizing circuit for effecting a expansion process on the pattern represented by said binary signals to produce expanded pattern signals; first connection data generating means connected to said binary digitizing circuit for examining the connectivity relationship between two selected points of the circuit pattern represented by said binary signals and producing first connection data signals representative of a connectivity relationship for said points; second connection data generating means connected to said expansion means for examining the connectivity relationship between said two selected points of the circuit pattern represented by said expansion pattern signals and producing second connection data signals representative of a connectivity relationship for said points; and comparison means for comparing said first and second connection data signals to design data signals for said two selected points for producing an output representing a determination of the defectiveness of the pattern based on said comparison.

Claim 26

An apparatus for detecting a defect of a circuit pattern comprising: image pickup means which senses an optical image of a circuit pattern and provides an electrical image signal; a binary digitizing circuit which transforms said electrical image signal into binary signals representing picture elements; contraction means connected to said binary digitizing circuit for effecting a contraction process on the pattern represented by said binary signals to produce contraction pattern signals; first connection data generating means connected to said binary digitizing circuit for examining the connectivity relationship between two selected points of the circuit pattern represented by said binary signals and producing first connection data signals representative of a connectivity relationship for said points; second connection data generating means connected to said contraction means for examining the connectivity relationship between said two selected points of the circuit pattern represented by said contraction pattern sigals and producing second connection data signals representative of a connectivity relationship for said points; and comparison means for comparing said first and second connection data signals to design data signals for said two selected points for producing an output representing a determination of the defectiveness of the pattern based on said comparison.

Claim 27

An apparatus for detecting a defect of a circuit pattern comprising: image pickup means which senses an optical image of a circuit pattern and provides an electrical image signal; a binary digitizing circuit which transforms said electrical image signal into binary signals representing picture elements; contraction means connected to said binary digitizing circuit for effecting a contraction process on the pattern represented by said binary signals to produce contraction pattern signals; first connection data generating means connected to said binary digitizing circuit for examining the connectivity relationship between two selected points of the circuit pattern represented by said binary signals and producing first connection data signals representative of a connectivity relationship for said points; second connection data generating means connected to said contraction means for examining the connectivity relationship between said two selected points of the circuit pattern represented by said contraction pattern sigals and producing second connection data signals representative of a connectivity relationship for said points; and comparison means for comparing said first and second connection data signals to design data signals for said two selected points for producing an output representing a determination of the defectiveness of the pattern based on said comparison.