CAPACITIVE FINGERPRINT SENSOR - MICROARRAY MICROELECTRONICS CORP LTD

Title:

CAPACITIVE FINGERPRINT SENSOR

Document Type and Number:

WIPO Patent Application WO/2017/092676

Kind Code:

A1

Abstract:

A capacitive fingerprint sensor performs fingerprint imaging by measuring capacitance differences of coupling capacitors formed between valleys and ridges of a fingerprint and corresponding units of a planar sensing electrode array. A C-Q-T-type capacitive fingerprint sensor indirectly measures a capacitor by utilizing two transforms including one from capacitance into an electric charge quantity and the other from the electric charge quantity to an integrated time, and can enhance a conversion efficiency from the capacitance to the electric charge quantity via coupling a drive signal to a human body, thus improving sensitivity of the sensor. The improved C-Q-T-type capacitive fingerprint sensor in the present invention employs, as an equivalent and replacement of the drive signal coupled with a human body, an inverse-phase drive signal coupled with the ground of the fingerprint sensor, thereby further improving the sensitivity of the sensor.

Inventors:

XU KEFENG (CN)
LI YANGYUAN (CN)

Application Number:

PCT/CN2016/108037

Publication Date:

June 08, 2017

Filing Date:

November 30, 2016

Export Citation:

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Assignee:

MICROARRAY MICROELECTRONICS CORP LTD (CN)

International Classes:

G06K9/00

Foreign References:

CN105335737A	2016-02-17
CN105046194A	2015-11-11
CN102954753A	2013-03-06
CN104880635A	2015-09-02
CN103714330A	2014-04-09
CN103149450A	2013-06-12
CN103902123A	2014-07-02
US20110163768A1	2011-07-07
CN201210403271A	2012-10-22
CN201410004072A	2014-01-06

Other References: