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:
Jul. 07, 2020
Filed:
Jan. 10, 2017
Ntn Corporation, Osaka-Shi, Osaka, JP;
Hiroaki Ohba, Shizuoka, JP;
NTN CORPORATION, Osaka, JP;
Abstract
A shape measuring apparatus includes: a light source; a two-beam interference objective lens; an imaging device; an observation optical system; a positioning device; and a control device. The control device calculates, for each unit region in the plurality of images obtained by the imaging device, as a focus position of the unit region, a position of the two-beam interference objective lens at which a luminance-based evaluation value is maximized over the plurality of images, and the control device measures a shape of a target object based on the focus position of each unit region in the plurality of images. The control device uses, as the evaluation value, a luminance of each unit region in the plurality of images as well as a value correlated with a difference between the luminance of the unit region and luminances of a plurality of unit regions adjacent to the unit region.