US Patent No. 10,637,437

AT-CUT CRYSTAL ELEMENT AND CRYSTAL RESONATOR


Patent No. 10,637,437
Issue Date April 28, 2020
Title At-cut Crystal Element And Crystal Resonator
Inventorship Hiroyuki Yamauchi, Saitama (JP)
Kazuhiko Osawa, Saitama (JP)
Shohei Takeda, Saitama (JP)
Assignee NIHON DEMPA KOGYO CO., LTD., Tokyo (JP)

Claim of US Patent No. 10,637,437

1. An AT-cut crystal element, comprising:side surfaces that intersect with a Z?-axis of a crystallographic axis of crystal,
at least one side surface of the side surfaces being constituted of three surfaces of a first surface, a second surface, and a third surface, wherein
the first surface being an m-surface of a quartz crystal,
the second surface intersecting with the first surface and being other than the m-surface,
the third surface intersecting with the second surface and being other than the m-surface.