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To improve a viewing angle characteristic as well as a light extraction effect, we fabricated nanoporous polymer film (NPF) as a scattering medium as well as a light extraction component. We designed two types of organic light emitting diodes (OLEDs) with strong microcavity effect containing two different hole transport layer (HTL) thickness (e.g. 30 nm and 60 nm) to investigate each optical behavior of NPF. Very interestingly, we could observe a significant enhancement of external quantum efficiency (EQE) for each device [30 nm thick HTL : 18.0 %, 60nm thick HTL : 31.6 %] when we attached 125 um thick PET film coated with NPF. Furthermore, NPF successfully suppress the viewing angle dependence to realize ideal angular emission even though it's somehow different from that of Lambertian distribution.

We have fabricated transparent inverted organic light-emitting diodes (OLEDs) using a metal mesh embedded conductive film (MEF) with a non-metal transparent conductor and a novel vacuum lamination method. The device with the proposed electrode exhibits higher transmittance, lower reflectance, and especially much more stable optical properties than those of the conventional OLEDs with thin metal top electrodes over an entire visible region. Moreover, lower driving voltage is also achieved due to the embedded metal mesh. We demonstrate its potential as a reliable transparent top electrode in various optoelectronic devices.

We report on a novel fabrication method for organic lightemitting diodes (OLEDs) by using a multilayered graphene (MLG) film and a lamination technique. The OLED structure with the MLG top electrode has higher transmittance and lower reflectance than the OLED structure with the conventional thin metal electrode. Moreover, higher luminous current efficiency of the device with the MLG top electrode has been achieved compared with that of the conventional bottom-emission OLEDs with aluminum metal electrode.

We suggest a new approach to improve both out-coupling efficiency and spectrum independency on viewing angle in transparent OLEDs by introducing a random nano-structured scattering layer where the waveguide mode can be minimized between the glass substrate and the ITO layer. As a result, total efficiency was remarkably enhanced in transparent OLEDs and we have achieved 52.6 lm/W with CRI 80 with over 50% of transmittance using the random nano-structured scattering layer.

We used the magnetic resonant wireless power transmission technology to lit thin OLED lighting panels. For the magnetic resonant wireless power transmission, we used small and thin four layer printed circuit board for the receiver. The resonant frequency is lowered up to 457 kHz for the electromagnetic regulation.

This paper reports on a study of the electrical properties of integrated organic light emitting diode (OLED) with an organic photo sensor (OPS) based on poly-3-hexylthiophene (P3HT) and [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) for emotional lighting applications. The emission characteristics exhibit the changes in the current and luminance of an OLED as a function of time when the OPS is exposed to different illumination levels from full dark to 500 m W/cm2 using a xenon lamp.

The stability of ZnO TFT under bias stress was investigated. Transparent ZnO thin films deposited by means of atomic layer deposition(ALD) and plasma enhanced atomic layer deposition(PEALD) at 100 °C were used as the active channel. The TFT with PEALD grown ZnO layer has better stability under bias stress than the TFT with ALD grown ZnO layer.

In this work, we report reflective colored organic light-emitting diodes (OLEDs) integrated with color-selective reflective filter (CSRF) and transparent OLEDs functioning as the reflective and emissive mode. To fabricate transparent OLEDs with low-reflective anode, the dry bonding technology of graphene anode was developed.

Various external actions can cause the formation of patterns. In this work, we describe the spontaneous formation of wrinkles in an organic material system. The appearance of the fairly complex wrinkle structures is ascribed to the stress release during UV curing process of the liquid prepolymer solution. The wrinkle structures introduced here are demonstrated to have a light extraction function.

Since the first demonstration of oxide TFT driving AM-OLED, oxide TFT technology has attracted explosive interesting and has been developed for the mass production. The performance of oxide TFT has been verified and the remained issue is bias temperature stability. In this paper, we report the effect of interface process including channel and back channel on the oxide TFT performance in a top gate and a bottom gate structure. We also demonstrate transparent AM-OLED driven by highly stable Al doped ZTO TFT.

We have fabricated the transparent bottom gate TFTs using Al and Sn-doped zinc indium oxide (AT-ZIO) as an active layer. The AT-ZIO active layer was deposited by RF magnetron sputtering at room temperature, and AT-ZIO TFT showed a field effect mobility of 15.6 cm2/Vs even before annealing. The mobility increased with increasing In2O3 content and post-annealing temperature. The AT-ZIO TFT exhibited afield effect mobility of 33 cm2/Vs, a sub-threshold swing of 0.08 V/dec, and an on/off current ratio of more than 109 after Al2O3 passivation and post-annealing. We have fabricated AMOLED panels with the bottom gate AT-ZIO TFT back-plane successfully.

We have examined post-annealing and passivation for the transparent bottom gate IGZO TFT having an inverse co-planar structure. The oxygen-vacuum two step annealing enhanced the field effect mobility up to 18 cm2/Vs and the sub-threshold swing down to 0.2 V/dec. However, the hysterysis and the bias stability problems could not be solved just by post-annealing. Thus, we have passivated the bottom gate IGZO TFTs with organic and inorganic materials. Ga2O3, Al2O3, SiO2 and some polymer materials were effective materials for passivations. The hysterysis and the stability of the TFTs were remarkably improved by the passivations.

We have fabricated 2.15 inch AM-OLED panel composed of 176 × 144 (106 dpi) transparent pixels driven by ZnO-TFT. Transparent ZnO thin film deposited by means of atomic layer deposition at 100°C was used for the active channel. The ZnO TFT had a mobility of 1.13cm2/V.s, a threshold voltage of 0.8V, and an on/off ratio of 106. The fabrication of the ZnO TFT array for AM-OLED display has been carried out with four-mask process. and the integration of the ZnO TFT array and the transparent OLED consisted of a transparent anode and cathode and organic layers led to really transparent display.