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. 23, 2019
Filed:
Dec. 16, 2015
Applicant:
Fujitsu Limited, Kawasaki-shi, Kanagawa, JP;
Inventors:
Assignee:
FUJITSU LIMITED, Kawasaki, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03B 5/32 (2006.01); H03B 5/36 (2006.01); H03H 9/10 (2006.01); G01H 15/00 (2006.01); G01N 27/02 (2006.01); G01R 23/02 (2006.01); G01R 27/16 (2006.01); G01R 29/22 (2006.01); G01R 31/28 (2006.01);
U.S. Cl.
CPC ...
G01N 27/02 (2013.01); G01H 15/00 (2013.01); G01N 27/028 (2013.01); G01R 23/02 (2013.01); G01R 27/16 (2013.01); G01R 29/22 (2013.01); G01R 31/2824 (2013.01); H03B 5/323 (2013.01); H03B 5/36 (2013.01); H03H 9/1021 (2013.01);
Abstract
A method for inspecting a crystal unit, the method includes: generating a sub-vibration in a crystal blank of the crystal unit by applying an input signal to a plurality of electrodes formed on the crystal blank; obtaining frequency characteristics of impedance between the plurality of electrodes from an output signal of the plurality of electrodes; and comparing the frequency characteristics obtained with reference frequency characteristics indicating quality of the crystal unit.