To study emission properties of white phosphorescent organic light emitting devices (PHOLEDs), we fabricated white PHOLEDs of ITO (150 nm) / NPB(30 nm) / TcTa(10 nm) / mCP(7.5 nm) / light-emitting layer(25 nm) / UGH3(5 nm) / Bphen(50 nm) / LiF(0.5nm) / Al(200 NM) structure. The total thickness of light-emitting layer with co-doping and blue-doping/ co-doping using a host-dopant system was 25 nm and the dopant of blue and red was FIrpic and Bt2Ir(acac) in UGH3 as host. respectively. The OLED characteristics were changed with position and thickness of doping layer and co-doping layer as light-emitting layer and the best performance seemed in structure of blue-doping(5 nm)/co-doping(20 nm) later. The white PHOLEDs showed the maximum current density of 34.5 mA /cm², maximum brightness of 5,731 cd/ m², maximum current efficiency of 34.8 cd/A, maximum power efficiency of 21.6lm/w, maximum quantum effiency of 15.6%, and a Commission International de L`Eclairage (CIE) coordinate of (0.367, 0.436) at 1,000 cd/m².

A Xe plasma flat lamp, which has been noticed as a new eco-friendly LCD (liquid crystal display) backlight, requires the improvement of the luminance and the luminous efficiency although it has several advantages. To improve the performance of a lamp, it is necessary to understand the effects of discharge variables on the luminous characteristics of the lamp. Since it is difficult to diagnose a lamp discharge experimentally, the numerical analysis can be used instead. In this study, the luminous characteristics of a planar type Xe plasma flat lamp were analyzed with the variation of an input voltage and a pulse frequency. The numerical analysis of a lamp discharge was then performed using a RCT (relaxation continuum) model and a LFA (local field approximation) model. The comparison with the experimental results showed that the RCT model is valid for the numerical analysis of the flat lamp. The numerical analysis also showed that the modifications of a high frequency component and a voltage falling rate in the input voltage waveform could improve the luminous characteristics of the lamp.