Welcome to Vidyasirimedhi Institute of Science and Technology.


Professor Dr. Vinich Promarak

Department of Materials Science and Engineering
School of Molecular Science and Engineering (MSE)
Tel. 033 014150
Email vinich.p@vistec.ac.th


Organic Light-Emitting Diodes (OLEDs) for Low Energy Consumption Lighting Panels


Research Overview

The OLED is expected to be the next generation lighting and to revolutionize the whole lighting and space concept. OLEDs do not need light distribution elements. Furthermore, in contrast with LED lighting components they are not a point source technology. An OLED lighting panel has ultrathin layers of organic matter. Every layer has a function, but the thickness is less than 1/1000 of a human hair. The thin OLED layer is then sandwiched between positive and negative electrodes, and gives off light when a current is applied. Optimization of light-emitting materials to achieve highly efficient, stable, OLED device and OLED lighting panels will open the way to unexpected developments towards practical technological devices.

Organic light-emitting diodes (OLEDs)

Organic light-emitting diodes (OLEDs) are semiconductors made of layers of thin organic materials only a few nanometers thick, which can potentially be mounted on a variety of flexible substrates such as glass, metal foil or plastic. Because OLEDs emit light in a diffuse way to form an area light source, they are a key part of a revolution in the rapidly-growing display market: fulfilling the dream of paper-thin, highly efficient displays with brilliant colors and amazing design flexibility. We believe that OLEDs represent the future of a vast array of completely new lighting applications. By combining color with shape, OLEDs can create a new ways of decorating and personalizing personal surroundings with light. Main parts of an OLED are substrate, anode, cathode and two organic layers (transport + emissive layer). The working principle of the OLEDs involves the current flow from the cathode to the anode through the organic layers. Firstly, electrons move from the conducting layers into the emissive layer. This leaves holes in the conductive layer where the electrons were removed. These holes jump to the emissive layer, where the electrons recombine with them. As the electrons drop into the holes, they release extra energy as light, thus becoming an organic light source.

Through their special properties (surface light source, transparent, flat, potentially flexible), OLEDs can open up new applications such as light tiles, light partitions or transparent light sources, which only emit light at night, by day or serve as a window. In addition to that, OLEDs can be integrated in installations, for example in kitchens and bathrooms, allowing revolutionary lighting design.

Benefit of OLED in lighting applications

  • OLED: Better quality of light, Human-friendly light, No glare or eye strain, No UV and No heat
  • Unlimited Design Possibilities: Thin & light, Flexible, Transparent
  • Structural Advantages: Uniform surface light with no heat

Applications for OLED lighting?

  • Study room lighting & study desk lamp
  • Lighting for window/shelf display where requiring quality light (High CRi)
  • Portable lighting for outdoor activities
  • Decorative lighting
  • Lighting fitted with curve surface (Flexible OLED)
  • Automotive lighting & aircraft lighting
  • Integrated lighting into construction materials such as glass or wall
Our research team at VISTEC has been developing variety of new light-emitting materials for OLEDs for many years. High efficiency OLED devices and lighting-panel prototypes have been fabricated from these new emitters. The aim of the research project is to develop new solution processable non-doped light-emitting materials for achieving highly efficient, stable, OLED devices and lighting-panels and to develop the OLED lighting panels to the application stage.

Selected Publications

  1. Thangtong, D. Meunmart, T. Sudyoadsuk, S. Jungsuttiwong, N. Prachumrak, T. Keawin, V. Promarak Chemical Communications, 2011, 47, 7122-7124.
  2. A. M. Thangthong, N. Prachumrak, R. Tarsang, T. Keawin, S. Jungsuttiwong, T. Sudyoadsuk, V. Promarak Journal of Materials Chemistry, 2012, 22, 6869-6877.
  3. T. Khanasa, N. Prachumrak, R. Rattanawan, S. Jungsuttiwong, T. Keawin, T. Sudyoadsuk, T. Tuntulani, V. Promarak Journal of Organic Chemistry, 2013, 78, 6702–6713.
  4. N. Prachumrak, S. Pojanasopa, S. Namuangruk, T. Kaewin, S. Jungsuttiwong, T. Sudyoadsuk, V. Promarak ACS Applied Materials & Interfaces, 2013, 5, 8694-8703.
  5. P. Moonsin, N. Prachumrak, S. Namuangruk, S. Jungsuttiwong, T. Keawin, T. Sudyoadsuk, V. Promarak Journal of Materials Chemistry C, 2014, 2, 5540-5552.
  6. A. Thangthong, N. Prachumrak, T. Sudyoadsuk, S. Namuangruk, T. Kaewin, S. Jungsuttiwong, N. Kungwan, V. Promarak Organic Electronics, 2015, 21, 117–125.
  7. T. Sangchart, A. Niroram, T. Kaewpuang, N. Prachumrak, S. Namuangruk, T. Sudyoadsuk, T. Keawin, S. Saengsuwan, S. Jungsuttiwong, S. Maensiri, N. Kungwan, V. Promarak RSC Advances, 2015, 5, 26569–26579

Research Group Members:

Prof. Dr. Vinich Promarak (Professor)
Dr. Pichaya Pattanasattayavong (Lecturer)
Assist. Prof. Dr. Taweesak Sudyoasuk
(Postdoctoral Research Fellow)
Dr. Anurach Poloek (Postdoctoral Research Fellow)
Dr. Rossatorn Muangpaisal(Postdoctoral Research Fellow)
Mr. Jakkapan Kumsampao
Mr. Phattananawee Nalaoh
Mr. Jirat Chatsirisupachai
Mr. Sebastian Broll
Ms.Namthip Khammultri