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:
Apr. 02, 2019
Filed:
Dec. 28, 2016
Nihon Dempa Kogyo Co., Ltd., Tokyo, JP;
Yoshiharu Sato, Saitama, JP;
Yoshiro Teshima, Saitama, JP;
Hirokazu Iwata, Saitama, JP;
Kazuhiro Hirota, Saitama, JP;
NIHON DEMPA KOGYO CO., LTD., Tokyo, JP;
Abstract
An AT-cut crystal element includes a crystal element having two side surfaces (namely, a Z'-surface) intersecting with a Z-axis of a crystallographic axis thereof. At least one of the two side surfaces is constituted of three of first to third surfaces. The first to the third surfaces meeting following conditions: the first to the third surfaces intersect with one another in this order and formed by rotating a principal surface of the crystal element by predetermined angles; and expressing the angle of the first surface as θ, a length of the first surface as D, a thickness of a part of the crystal element having the principal surface as t, and M=D/t, and a conversion percentage as fn (M, (θ)), the θand the M are set such that the conversion percentage fn (M, (θ)) becomes a predetermined value Th or less.