In this paper, we propose a novel voltage programmed pixel circuit based on amorphous-indium-gallium-zinc-oxide thin-film transistors (a-IGZO TFTs) for active-matrix organic light-emitting displays. Through the extensive simulation work based on a-IGZO TFT and OLED models, we confirm that the proposed pixel circuit can compensate for threshold voltage variations of TFTs and OLED degradation over wide dynamic range (~104) of OLED current as well as achieve a high pixel aperture ratio with the suppressed OLED current error rate below 9%.
The paper presents a wearable textile antenna embroidered on a fabric for wireless power transfer systems. A planar spiral coil was generated with the conductive thread on a cotton substrate, and was connected to a rectifier circuit fabricated on flexible polyethylene terephthalate film to constitute a bendable receiver by the magnetic resonance. At a resonance frequency of 6.78 MHz, the proposed system could achieve −5.51 dB transfer efficiency and 12.75 mW power transmission at a distance of 15 cm. It was also demonstrated that the resonance frequency and transmitted power of the proposed system could be maintained as the same even when the system was bent conformingly to the surface curvature of the human body model for a bending radius up to 50 mm or larger.
Ultrahigh-resolution patterning with high-throughput and high-fidelity is highly in demand for expanding the potential of organic light-emitting diodes (OLEDs) from mobile and TV displays into near-to-eye microdisplays. However, current patterning techniques so far suffer from low resolution, consecutive pattern for RGB pixelation, low pattern fidelity, and throughput issue. Here, we present a silicone engineered anisotropic lithography of the organic light-emitting semiconductor (OLES) that in-situ forms a non-volatile etch-blocking layer during reactive ion etching. This unique feature not only slows the etch rate but also enhances the anisotropy of etch direction, leading to gain delicate control in forming ultrahigh-density multicolor OLES patterns (up to 4500 pixels per inch) through photolithography. This patterning strategy inspired by silicon etching chemistry is expected to provide new insights into ultrahigh-density OLED microdisplays.