Directional lighting and method to distinguish three...

Details Directional lighting and method to distinguish three... Directional lighting and method to distinguish three...

2005-05-31

2005-05-31

Mehta, Bhavesh M. (Department: 2625)

Image analysis

Applications

Manufacturing or product inspection

C382S154000, C382S190000, C348S126000, C348S131000, C348S208800, C356S237400

Reexamination Certificate

active

06901160

ABSTRACT:
The present invention provides a method and an apparatus for evaluating the surfaces of substrates for three dimensional defects. The present invention uses low-angled lighting positioned on opposite sides of the substrate. A camera positioned above the substrate captures two images thereof, one using the first light source and one using the second. The first and second images are subtracted from one another to create a third image. Camera data suggestive of three dimensional features is emphasized by subtracting the two images and can be evaluated. A fourth image may be created by selecting the minimum values between the first and second images on a point-by-point basis. The fourth image also provides useful information in evaluating three dimensional defects.

REFERENCES:
patent: 5608547 (1997-03-01), Nakatani et al.
patent: 5774574 (1998-06-01), Hoki
patent: 5859698 (1999-01-01), Chau et al.
patent: 5920387 (1999-07-01), Nakajo et al.
patent: 5943125 (1999-08-01), King et al.
patent: 5949901 (1999-09-01), Nichani et al.
patent: 6177682 (2001-01-01), Bartulovic et al.
patent: 6256088 (2001-07-01), Gordon
patent: 6353222 (2002-03-01), Dotan
patent: 6658144 (2003-12-01), Hatab
patent: 19511534 (1996-10-01), None
patent: 0 898 163 (1999-02-01), None
patent: 1 030 173 (2000-08-01), None
patent: 63215952 (1988-08-01), None
patent: 04279848 (1992-05-01), None
PCT International Search Report (Application No. PCT/US 01/13477).

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