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:
Nov. 14, 2017
Filed:
Dec. 25, 2014
Sumco Corporation, Minato-ku, Tokyo, JP;
Toshiaki Sudo, Akita, JP;
Tadahiro Sato, Akita, JP;
Ken Kitahara, Akita, JP;
Eriko Kitahara, Akita, JP;
SUMCO CORPORATION, Tokyo, JP;
Abstract
In an embodiment, a distortion-measuring apparatus for measuring a distortion distribution of an entire vitreous silica crucible in a non-destructive way includes: a light source; a first polarizerand a first quarter-wave platedisposed between the light sourceand an outer surface of a vitreous silica crucible wall; a cameradisposed inside of a vitreous silica crucible; a camera control mechanismconfigured to control a photographing direction of the camera; a second polarizerand a second quarter-wave platedisposed between the cameraand an inner surface of the vitreous silica crucible wall. An optical axis of the second quarter-wave plateinclines 90 degrees with respect to the first quarter-wave plate