Related Experiment Video
Updated: Jun 23, 2026
07:44
Production and Characterization of Vacuum Deposited Organic Light Emitting Diodes
Published on: November 16, 2018
Polarized micro-cavity organic light-emitting devices.
Byoungchoo Park1, Mina Kim, Chan Hyuk Park
1Department of Electrophysics, Kwangwoon University, Seoul, Korea. bcpark@kw.ac.kr
Optics Express
|April 29, 2009
Summary
This study shows that polarized micro-cavity Organic Light-Emitting Devices (OLEDs) emit light efficiently at low voltages. The emission
Area of Science:
- Organic Light-Emitting Devices (OLEDs)
- Photonic Crystals (PCs)
- Optoelectronics
Background:
- Anisotropic one-dimensional (1-D) photonic crystal (PC) films offer unique optical properties.
- Micro-cavity structures are crucial for controlling light emission in OLEDs.
Purpose of the Study:
- To investigate light emission characteristics of a polarized micro-cavity OLED using a flexible anisotropic 1-D PC film.
- To understand the relationship between light polarization and emission modes.
Main Methods:
- Fabrication of a flexible, anisotropic 1-D PC film substrate for the OLED.
- Characterization of electroluminescent (EL) emissions under varying polarization states.
- Analysis of peak wavelengths and bandwidths of emitted light.
Main Results:
- Luminous EL emissions were achieved at low operating voltages.
- Peak emission wavelengths correlated with split eigen modes at the high-energy band edges of the PC film.
- Emission modes showed strong dependence on the polarization direction relative to the PC's optical axes.
Conclusions:
- The polarization and emission mode of the micro-cavity OLED can be precisely controlled.
- Selection of the appropriate optical axis of the anisotropic 1-D PC film allows for tailored light emission properties.
Related Concept Videos
01:16Biasing of P-N Junction
The operation of a p-n junction diode involves various biasing conditions, including forward bias, reverse bias, and equilibrium.
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
01:31Dielectric Polarization in a Capacitor
The presence of a dielectric medium in a capacitor not only changes the voltage and capacitance but also affects the electric field. In general, dielectrics can be of two types: polar and nonpolar. In a polar dielectric, the positive and negative charges in the molecules are separated by a distance and hence have a permanent dipole moment. In contrast, no such charge separation exists in a nonpolar dielectric, however the nonpolar molecules get polarized in the presence of an external electric...
01:14Photoluminescence: Applications
Photoluminescence offers a wide range of applications due to its inherent sensitivity and selectivity. This technique allows for both direct and indirect analyses of the analyte. Direct quantitative analysis is possible when the analyte exhibits a favorable quantum yield for fluorescence or phosphorescence. However, an indirect analysis may be feasible if the analyte is not fluorescent or phosphorescent, or if the quantum yield is unfavorable. Indirect methods include reacting the analyte with...
01:29Potential Due to a Polarized Object
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...