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:
Sep. 24, 1991
Filed:
May. 03, 1990
Motohito Hino, Nagoya, JP;
Abstract
An optical surface roughness measuring apparatus for measuring roughness of a surface of a subject, by irradiating the surface with two linearly polarized beams of light which have orthogonal planes of polarization and different frequencies, and detecting a change in a beat frequency of the two beams reflected by the surface. The optical surface measuring apparatus includes a laser device for producing two linearly polarized laser beams as the two linearly polarized beams, and an optical device having a single optical path between the laser device and the surface of the subject, so that the two linearly polarized laser beams are propagated from the laser device toward the surface along the single optical path. The optical device includes a double-focus lens, and is operable for converging one of the two laser beams so as to irradiate a reading spot on the surface of the subject, and converting the other of the two laser beams into parallel ray of light for irradiating an area on the surface, the area being aligned with the reading spot and having a diameter larger than the reading spot.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile