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. 21, 2020
Filed:
May. 21, 2018
Guangdong Oppo Mobile Telecommunications Corp., Ltd., Dongguan, Guangdong, CN;
Qiang Zhang, Guangdong, CN;
Lizhong Wang, Guangdong, CN;
Haitao Zhou, Guangdong, CN;
Kui Jiang, Guangdong, CN;
Wei He, Guangdong, CN;
GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD., Dongguan, CN;
Abstract
A method and an apparatus for determining existence of a foreign material on a surface of a fingerprint sensor of a terminal are provided. The method includes the following. A current capacitance value of the fingerprint sensor of the terminal is obtained. A first difference between the current capacitance value and a preset capacitance reference value is calculated. Determine that the foreign material is present on the surface of the fingerprint sensor when the first difference is within a preset foreign-material threshold range. The preset capacitance reference value is a capacitance value tested with no foreign material on the surface of the fingerprint sensor before leaving the factory and is stored in a system in advance. The preset foreign-material threshold range is set in advance according to experimental data of capacitance-change tests performed on the fingerprint sensor when different conductive foreign materials are on the surface of the fingerprint sensor.