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:
Nov. 28, 2000
Filed:
Jul. 28, 1998
Toshihide Kuriyama, Tokyo, JP;
Michihisa Suga, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A fingerprint sensor is disclosed, which employs a plurality of tactile sensors, each has an elastic insulating body between a member of an electrically conductive material, i.e., a gate electrode, and an insulating film deposited on a channel region of a field-effect transistor (FET). The channel region is formed between a source region and a drain region. Each of the tactile sensors is connected in series with a transistor that serves as a source of constant or steady current to form a source follower circuit. With the source follower circuit, output of each of the tactile sensors is converted into source voltage. The source voltage of each of the source follower circuits is extracted via a first switching element at a common output terminal. The source follower circuits are connected via a second switching element to a source of electric power.