Publications by authors named "Seok-Whan Chung"
Article Synopsis
- The paper introduces a fine dust detection system that utilizes surface acoustic wave (SAW) sensors, which change their resonance points when exposed to fine dust.
- The system includes two channels—a sensing channel and a reference channel—each equipped with a SAW oscillator and a 20-bit asynchronous counter to measure frequency differences.
- The proposed circuit demonstrates a high frequency resolution of 0.95 parts per million (ppm) while operating at 460 MHz and was fabricated using a TSMC 130 nm CMOS process.
In this study, a mutual capacitive-type on-screen fingerprint sensor, which can recognize fingerprints on a display screen to provide smartphones with full-screen displays with a minimal bezel area, is fabricated. On-screen fingerprint sensors are fabricated using an indium tin oxide transparent conductor with a sheet resistance of ~10 Ω/sq. and a transmittance of ~94% (~86% with the substrate effect) in the visible wavelength range, and assembled onto a display panel.
View Article and Find Full Text PDFThe display quality of touchscreen devices with on-screen fingerprint sensors is reduced by moiré patterns, interference phenomena caused by an overlap between the pixel pattern of the display, and the electrode pattern of the fingerprint sensor. A promising strategy for resolving this issue is to reduce the visibility of the moiré pattern, by including a filling layer with a transmittance similar to that of the electrodes, between the different patterns. We propose a moiré-free fingerprint sensor that uses an oxide-metal-oxide (IZO/Ag/IZO) multilayer as a highly transparent electrode.
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