Optical diffraction method and apparatus for integrated circuit lead inspection
First Claim
Patent Images
1. A method for detecting damage of leads arranged in a generally parallel periodic pattern, comprising the steps of:
- (a) directing a coherent light beam at a plurality of adjacent leads;
(b) detecting an image at a distance from the leads at which said light beam would form a diffraction image having substantially uniform intensity when said leads form a substantially uniform pattern;
(c) moving said pattern of leads and said light beam with respect to each other; and
(d) detecting damage of leads from variation in intensity of the detected image.
2 Assignments
0 Petitions
Accused Products
Abstract
A technique for detecting damage of leads arranged in a generally parallel periodic pattern, includes the following steps: directing a coherent light beam at a plurality of adjacent leads; detecting an image at a distance from the leads at which the light beam would form a diffraction image having substantially uniform intensity when the leads form a substantially uniform pattern; moving the pattern of leads and the light beam with respect to each other; and detecting damage of leads from variation in intensity of the detected image.
-
Citations
20 Claims
-
1. A method for detecting damage of leads arranged in a generally parallel periodic pattern, comprising the steps of:
-
(a) directing a coherent light beam at a plurality of adjacent leads; (b) detecting an image at a distance from the leads at which said light beam would form a diffraction image having substantially uniform intensity when said leads form a substantially uniform pattern; (c) moving said pattern of leads and said light beam with respect to each other; and (d) detecting damage of leads from variation in intensity of the detected image. - View Dependent Claims (2, 3, 4, 5)
-
-
6. Apparatus for detecting damage of leads arranged in a generally parallel periodic pattern, comprising:
-
means for directing a coherent light beam at a plurality of adjacent leads; means for detecting an image at a distance from the leads at which said light beam would form a diffraction image having substantially uniform intensity when said leads form a substantially uniform pattern; means for moving said pattern of leads and said light beam with respect to each other; and means for determining the variation in intensity of the detected image. - View Dependent Claims (7, 8, 9, 10, 11, 12, 13)
-
-
14. Apparatus for detecting damage of leads arranged in a generally parallel periodic pattern, comprising:
-
means for directing a coherent light beam at plurality of adjacent leads; means for detecting an image at a distance from the leads at which said light beam would form a diffraction image having substantially uniform intensity when said leads form a substantially uniform pattern, said means for detecting an image comprising a photodetector array; and means for determining the variation in intensity of the detected image. - View Dependent Claims (15, 16, 17, 18, 19, 20)
-
Specification