International Business Machines Corporation

Pemstar, Inc.

Arlen John Bowen

Nathaniel C Anderson

Robert Duane Ahmann

Randy J Bornhorst

David L Erickson

David George Nutt

Venkat R Koka

Ralph Emil Beastrom

Daniel W Jewell

Ronald James Keller

The present invention relates to a head tester for testing heads having a read element and a write element. The tester comprises a substrate on which a read coil is positioned to be sensitive to the write element of the head. A write coil is also formed on the substrate and this coil is positioned such that the read element of the head to be tested is sensitive to the write coil.

Magnetic head tester with write coil and read coil

The present invention includes a system for monitoring surface structures on a planar surface utilizing a radiation source emitting a beam. The planar surface has various surface structure types, including a plurality of grooves therein which intersect at various angles which are equal to or less than a predetermined maximum angle. The system includes an apparatus for directing the beam to the planar surface along an optical axis perpendicular to the planar surface resulting in radiation being scattered from the planar surface and a reference beam being specularly reflected from the planar surface. The system also includes detector responsive to radiation scattered from the planar surface. This detector produces a first signal representative thereof. Also provided is a spatial filter for filtering radiation scattered from the planar surface to allow only radiation from at least selected one of the plurality of surface structure types to reach the detector responsive to radiation scattered from the planar surface. The system may also include a detector responsive to the reference beam, producing a second signal in response to the reference beam and a circuit for producing a final signal from the first signal and the second signal.

Optical inspection system utilizing wedge shaped spatial filter

The burnishing tool has a plurality of holes in the planar surface which engages the flexible magnetic disk. Each hole contains a burnishing blade positioned at 45.degree. to the direction of motion. A manifold connects each hole to a vacuum pump which draws air into the holes causing the flexible magnetic disk to fly against the planar surface. The vacuum also removes the debris from the burnishing tool.

Apparatus and method for burnishing magnetic disks

A document card reader including a row of light sources transmitting light through a corresponding series of column-like cavities within a pair of members between which a document card with punched openings therethrough may move and a convex lens placed so as to receive light transmitted through the document card openings and transmit the light from all of the openings to a photodetector positioned at substantially the focal point of the lens.

Multiplexing document card reader with convex lens

Growing community of inventors

Rochester, MN, United States of America

Arlen John Bowen