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:
Aug. 08, 2000
Filed:
Apr. 28, 1997
Wayne Isami Imaino, San Jose, CA (US);
Anthony Juliana, Jr, San Jose, CA (US);
Milton Russell Latta, San Jose, CA (US);
Charles H Lee, San Jose, CA (US);
Wai Cheung Leung, San Jose, CA (US);
Hal J Rosen, Los Gatos, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A laser based inspection tool (LIT) for inspecting planar surfaces is described. In a preferred embodiment the LIT can simultaneously inspect both planar surfaces of disks for use in disk drives. In an embodiment of the invention, the incident beam is directed onto the surface to be inspected at an angle slightly offset from perpendicular so that the reflected beam is physically separated from the incident beam. Although slightly offset the reflected beam is routed back through the telecentric lens and scanner which are used for the incident beam. Preferably an aperture mask is placed in the path of the reflected beam and the incident beam to limit the cone of scattered light. Since the incident and reflected beams are physically separated, there may be an aperture for each beam, but the two masks may be physically connected. The aperture masks may also be used for alignment adjustments of the beams.