Format

Send to

Choose Destination
Sensors (Basel). 2018 Jan 19;18(1). pii: E293. doi: 10.3390/s18010293.

Transparent Fingerprint Sensor System for Large Flat Panel Display.

Author information

1
Ulsan National Institute of Science and Technology, School of Electrical & Electronic Engineering, Ulsan 44919, Korea. stepkr@unist.ac.kr.
2
Electronics and Telecommunications Research Institute, Reality Device Research Division, Daejeon 34129, Korea. jepi@etri.re.kr.
3
Electronics and Telecommunications Research Institute, Reality Device Research Division, Daejeon 34129, Korea. helloshcho@etri.re.kr.
4
Electronics and Telecommunications Research Institute, Reality Device Research Division, Daejeon 34129, Korea. lovesky@etri.re.kr.
5
Electronics and Telecommunications Research Institute, Reality Device Research Division, Daejeon 34129, Korea. kang2476@etri.re.kr.
6
CrucialTec, Pankyo 13486, Korea. lovesky@etri.re.kr.
7
CrucialTec, Pankyo 13486, Korea. hwang-cs@etri.re.kr.
8
Ulsan National Institute of Science and Technology, School of Electrical & Electronic Engineering, Ulsan 44919, Korea. myunghee.lee@unist.ac.kr.

Abstract

In this paper, we introduce a transparent fingerprint sensing system using a thin film transistor (TFT) sensor panel, based on a self-capacitive sensing scheme. An armorphousindium gallium zinc oxide (a-IGZO) TFT sensor array and associated custom Read-Out IC (ROIC) are implemented for the system. The sensor panel has a 200 × 200 pixel array and each pixel size is as small as 50 μm × 50 μm. The ROIC uses only eight analog front-end (AFE) amplifier stages along with a successive approximation analog-to-digital converter (SAR ADC). To get the fingerprint image data from the sensor array, the ROIC senses a capacitance, which is formed by a cover glass material between a human finger and an electrode of each pixel of the sensor array. Three methods are reviewed for estimating the self-capacitance. The measurement result demonstrates that the transparent fingerprint sensor system has an ability to differentiate a human finger's ridges and valleys through the fingerprint sensor array.

KEYWORDS:

a-IGZO thin film transistors (TFTs); fingerprint; readout integrated circuit (ROIC); sensor array; transparent

Supplemental Content

Full text links

Icon for Multidisciplinary Digital Publishing Institute (MDPI) Icon for PubMed Central
Loading ...
Support Center