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Integrating organic light-emitting diodes (OLEDs) with light therapy can significantly advance biomedical applications by offering non-invasive, precise, and customizable treatments. Developing innovative device designs and performing cellular tests is essential to assess the safety and effect of OLED-based light therapies in dermatology. As such, a wearable OLED medical device prototype has been created for easy attachment to the body, ensuring consistent exposure to skin injuries due to its comfortable fit and user-friendly operation. Moreover, it has demonstrated effectiveness in enhancing wound healing, as indicated by a max 23% increase in fibroblast proliferation at the cellular level. [ABSTRACT FROM AUTHOR]

The characteristics of the discharge modes in the microplasma generated in a plasma display with a coplanar gap and an auxiliary electrode were investigated in accordance with various plate gaps and coplanar gaps. The measurement results of the discharge current peak time, discharge current, and luminous efficacy showed that modes 2 and 3 appeared in the microplasma in the cases of various plate gaps and coplanar gaps and that the luminous efficacy increased in mode 2 and decreased in mode 3. In addition, a stabilized microplasma in a plasma display with an auxiliary electrode was obtained when the plate gap was longer than the coplanar gap, and the maximum luminous efficacy was obtained when the plate gap was similar to the coplanar gap. According to the measurement results, the discharge modes and the parametric studies are attractive to obtain and design for high luminous efficacy in a plasma display with a coplanar gap and an auxiliary electrode. Index Terms--Auxiliary electrode, coplanar gap, discharge current, discharge current peak time, discharge mode, luminous efficacy, microplasma, plasma display, plate gap.

Variation of wall voltage and priming effect due to an auxiliary electrode are investigated with the aim of attaining a better understanding of the discharge phenomenon in an ac plasma display panel with an auxiliary electrode. A periodic positive pulse, which is applied to the auxiliary electrode during afterglow, reduced wall charges accumulated on the auxiliary and sustain electrodes so that discharge current decreased with an increase of auxiliary-pulse voltage. In addition, the auxiliary pulse influenced on the priming particles so that the optical output was not changed as much as the reduced current and sustain voltage was lowered. Based on these results, modified auxiliary-pulse waveforms, i.e., dual auxiliary pulses, were applied to the auxiliary electrode to utilize more priming particles to improve luminous efficacy. The proposed auxiliary waveforms improved IR efficiency by 10%-15% as compared to that obtained with a single auxiliary pulse. Index Terms--Auxiliary electrode, detecting pulse, plasma display panel (PDP), priming effect, wall voltage.

The microplasma modes generated in a plasma display with a coplanar gap and an auxiliary electrode were investigated using the discharge current peak time (discharge delay) and discharge current. Three types of modes were classified as follows: Mode 1) showed a decrease in both the discharge current and the discharge delay, Mode 2) showed a decrease in the discharge current and an increase in the discharge delay, and Mode 3) showed an increase in the discharge current and a decrease in the discharge delay. The infrared efficiency increased in Modes 1) and 2) with an increase in the auxiliary pulse voltage. However, in Mode 3), the IR efficiency started to decrease. According to the measurement results, Modes 1) and 2) are suitable for microplasma generated in a coplanar gap with an auxiliary electrode to obtain high efficacy. Index Terms--Auxiliary electrode, coplanar gap, discharge current peak time, discharge delay, infrared (IR) efficiency, IR peak time, microplasma, plasma display.

In this study, the basic characteristics of an address discharge have been investigated on the dependence of an address pulse voltage and its characteristics were analyzed by the wall voltage measurement method. During the address operation, the discharge between an address electrode and a scan electrode is first generated by an address pulse voltage and then the discharge between a scan electrode and a common electrode is induced. The resultant wall voltage between the address electrode and a scan electrode is strongly dependent on an address pulse voltage while the resultant wall voltage between a scan electrode and a common electrode is roughly independent on an address pulse voltage. Index Terms--Address discharge, wall voltage, wall voltage measurement method.

According to the viewpoint of a driving scheme, the luminance and luminous efficiency is mainly determined during the sustain period. Therefore, it is very important to understand the characteristics of the wall voltage during the sustain period, which is essential to design the driving pulse scheme. In this study, the quantitative analysis of the wall voltage has been carried by the wall voltage measurement method during the sustain period. The initial difference of the wall voltage is sharply stabilized due to the sustain discharges and it is mainly determined by the sustain voltage. The wall voltage between the sustain electrodes is changed symmetrically for the reference voltage level, while the wall voltage between the address and sustain electrode is positively sustained which is roughly mean value of the total effective voltage. Index Terms--Priming effects, sustain period, wall voltage, wall voltage measurement method.

The temperature-dependent characteristics of ac plasma display panels (PDPs) are investigated, based on various case studies using a conventional driving scheme with reset pulses. Though the main factor of the thermal effects is caused by strong sustain discharges, it is not only caused by the panel characteristics, but also by the temperature-dependent characteristics of the driving system. One important thermal effect is a decreased breakdown voltage due to an increase in the panel temperature. Therefore, these results may be helpful in solving image-sticking and temperature-related phenomena. Index Terms--Image sticking, light emission, reset discharge, sustain discharge, thermal effects.

The change in the surface condition of the MgO thin film in an ac plasma display panel during the discharge aging process is studied and reported. The superficial layer on the MgO thin film was created during the discharge aging process, which was related to the minimum sustain voltage and the light intensity emitted from the Neon+Xenon gas mixture discharge.

Discharge characteristics of Ne+N[subscript 2] gas mixtures are studied for possible use in a plasma display panel.

The temporal effects of charged and metastable particles in the micro-discharges of an ac plasma display panel (ac-PDP) were investigated under actual driving conditions. The discharge gas used in the 4-in PDP was Neon + 4% Xenon. The discharge characteristics in terms of the time scale related to the space-charge decay, wall charge decay, metastable decay, and charge accumulation were investigated using a pulse technique. For Neon+4% Xenon gas-mixture discharges of 500 torr, 4 [micro]s was related to the time scale of the space-charge decay and wall-charge accumulation time. The minimum sustain voltage started to dramatically increase at 20 [micro]s, which was related to the time scale of the metastable particles. Whereas, after 40 [micro]s, the minimum sustain voltage slowly increased with a slope of 0.01581, which was related to the inverse of the time scale of the wall charge decay. Index Terms--Charge accumulation, plasma display panel (PDP), space charge, wall charge, wall-charge decay.

The effects of auxiliary voltage pulses on the improvement of luminance and luminous efficiency are examined in the surface-discharge of a 4-in AC plasma display panel (PDP) test panel.

Research into luminous efficiency of alternate current plasma display panels is presented. A new type of sustain waveform, with a longer discharge at the rising edge and self-erasing discharge at the falling edge, is proposed.

The authors examine the mechanics of plasma displays for use in high-definition television. Topics include cylindrical hollow cathodes, photoluminescence, and abnormal glowing

The author describes a new design for plasma displays. Topics include micorbridges, hollow cathode tubes, and glow levels.

A research on the microbridge plasma display revealed that its optimum operating pressure range for a 20 mum gap is 700-900 Torr, which is based on both breakdown voltage and luminance data. It was noted that this operating pressure is two to three times more that those of conventional plasma display panels. Thus, an increase in panel life is expected as this works in accord with the fifth power of the gas pressure when current limiting techniques are used.

A numerical analysis of the microdischarge in a plasma display panel have been made by using 2-dimensional multifluid equations. The discharge gas is used as Ne + Ar 0.1% in a state of non-LTE glow. The distributions of the microscopic variables such as the density, temperature, velocity of the charged particles and the density of the uncharged particles are obtained. The distributions of excited species are examined during glow and afterglow. From the simulation results, the nondischarge pulses applied to the auxiliary anode confine the plasma to the core of the microdischarge. It is found that metastable species and other excited species are locally confined around the auxiliary anode during glow and afterglow. Locally confined particles indirectly due to the nondischarge pulses play a role to improve the characteristics of the DC plasma display panel.

As the demand for flexible, rollable, and foldable displays grows, various state-of-the-art component technologies, including thin-film transistors (TFTs), electrodes, thin-film encapsulations (TFEs), and touch screen panels, have been developed based on organic light-emitting diodes (OLEDs) with flexible organic layers. Developing highly reliable flexible OLEDs is essential to realize flexible displays, but the flexible encapsulation technology still has technical difficulties and issues to be addressed. This review covers the recent developments in encapsulation technologies, particularly their material and structural designs, for highly reliable, flexible OLEDs. The solution concepts for the existing technical hurdles in flexible encapsulations are addressed. Among the various advanced flexible encapsulation technologies developed so far, neutral-axis engineering with a thin metal layer and a crack arrester is introduced. [ABSTRACT FROM AUTHOR]