OLEDs, performance measurement

Methods to determine or justify the utility of the electron transport properties of ETM are TOF electron mobility and electron-only diode device measurement as well as the overall OLED performance. 

The development and manufacture of organic light-emitting diodes (OLEDs) have demanded the use of the most advanced microstructural characterization techniques and sophisticated performance measurement devices [1-14], In this chapter, we will briefly describe these techniques and devices and review how scientists and engineers utilize them to improve the performance of OLEDs. 

In conclusion, we have presented many microstructural characterization and performance measurement techniques, together with examples of how to use these techniques to improve the performance of OLEDs. Seeing the enormous progress recently, we expect more and more OLED-related products will be used in our daily life. 

Characterizing the performance of the OLED devices requires an understanding of how the device functions and how the performance is measured. First, we discuss the subjective visual response in relation to the objective emission of light. Then we describe basic measurements and efficiency calculations. Next, we describe energy levels in OLED devices. Finally, we discuss the lifetime measurements. 

Performance of Several OLEDs Made by UDC. Both Luminous Efficiency and Luminance Were Measured at 1 mA/cm2. Initial Luminance for Red Is at 300 cd/m2 and 600 cd/m2 for Green in Lifetime Test... 

Judging from the present OLED status, the most important research was Partridge s report on the EL utilized poly(vinyl carbazole) (PVCz) thin films in 1982.26-29 He used the 500-nm-thick PVCz thin films doped with fluorescent molecules as an emissive center, equipped with the efficient hole-injection electrode (SbCls/PVCz) and the electron-injection electrode (cesium) as a low-workfunction metal. Although no quantitative measurement of luminance was described, surprisingly the injection current density reached 1 mA/cm2. Nowadays, we can fabricate very similar OLED devices with superior EL performance. Thus, Partridge s device contributed to establishing the prototypes of present OLED devices. 

Figures 7 and 8 show two different designs with a different number of layers in the metal-dielectric AR part of the structure, along with their calculated performances (reflectance and luminance spectra). The complex refractive index of all layers were measured from films deposited in the same conditions as our devices. When compared to the performance of a conventional OLED shown in Fig. 3(b) and (c), we see that the new designs reduce the reflectance to 2% and less, which is 25 times less than that of a typical OLED, and that the emission is of the same order of magnitude.

Despite the established sensing approach, in particular for gas phase measurements, extensive studies of optical O2 sensors are still continuing in an effort to enhance sensor performance, reduce sensor cost and size, simplify fabrication, and develop an O2 sensor that is compatible with in vivo biomedical monitoring [56]. Development of field deployable, compact sensors such as those envisioned for the structurally integrated OLED-based platform is therefore expected to be beneficial for the varied needs of gas... 

A PS PtOEP film was drop cast on the second, third, fourth, and fifth pairs when viewed in color, these pairs are orange due to the superposition of the green Alqg OLED EL and the red PtOEP PL. A GOx-doped sol-gel film was deposited on the third pair, while AOx and LOx were contained each in a separate glass well, whose base was the PtOEP-doped PS film, above pairs 4 and 5, respectively. The measurement was performed using a PMT. 

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