Methods and apparatus for machine vision inspection using single and multiple templates or patterns
AssigneeCognex Corporation
InventorsIvan Bachelder, Aaron Wallack
Life of this patent
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Abstract
A method for rapid determination of the position and/or orientation of a semiconductor device, electronic component or other object includes performing multiple times an operation of matching a pattern against an image. The matching operation finds the location, if any, of a respective pattern in the image and determines the degree of match. The position and orientation of the object is determined from the results of one of the matching operations, for example, from the operation that revealed the highest degree of match.
Claims11
A machine vision method for determining any of a location and an orientation in an image of an electronic component handled by a suction nozzle or other part-handling apparatus, the method comprising the steps of:
- A. performing plural times a step of matching a pattern with the same image, each time matching a different pattern, each pattern modeling one or more respective portions of the electronic component,
- B. each matching step including the steps of (i) finding a location, if any, of the respective pattern in the image, (ii) determining a degree of match between the respective pattern and the image, (iii) determining any of a position and an orientation of the electronic component based on results of the matching step, wherein the patterns are selected so as to match, individually or in combination, at least a majority of expected imaged portions of the electronic component under expected conditions of execution of the method,
- C. the performing step including (i) inspecting the image to determine a condition of the electronic component as a result of any of a defect in the component and an error in handling of the component by the suction nozzle or other part-handling apparatus, and (ii) rejecting a determination of any of a position and an orientation of the electronic component based on its condition,
- D. the inspecting step including determining a condition of the electronic component as a result of handling by the suction nozzle or other part-handling apparatus by, any of (i) finding in the image a shape corresponding to a part-handling apparatus, and (ii) finding in the image a shape corresponding to a suction nozzle.
Dependencies are inferred from the claim text.