The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 23, 1987
Filed:
Dec. 07, 1984
Applicant:
Inventor:
Mitsuyoshi Koizumi, Yokohama, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
356237 ; 250563 ; 250572 ;
Abstract
Method and apparatus for inspecting surface defects of a sample in which oblique illumination is applied onto a surface of the sample and in which illuminance of reflected beams generated from the surface is measured. Shading plate having double pinholes or double slits is used as means for shading a scattered beam from aventurine prominences of the sample surface to fully shade the scattered beam so that the inspection is accurately executed.