White OLEDs for Displays and General Lighting
In 1993, we developed white-light-emitting OLEDs for the first time. Since then, the performance of white OLEDs has steadily improved and, today, they are considered to be the light source of the next generation. OLED displays based on white OLEDs have also been developed and large-size displays have been commercialized. Recently, high quantum efficiencies (QEs) are obtained by using phosphorescent emitters such as iridium complexes. External QE of 25—30% was achieved for blue, green and red OLEDs, which correspond to the internal QE of nearly 100%. Device lifetime at high luminance levels, which is required for general lighting, is significantly improved by using the multiphoton structure. By combining the above techniques, OLEDs can be extremely efficient and possess extremely long lifetime, even at high luminance level. In 2010, Lumiotec Inc. has started small-scale production of white OLED panels in Yonezawa, and luminaires using their panels have been commercialized. In this talk, recent progress in white OLEDs will be discussed.
About Junji Kido
Junji Kido was born in Osaka, Japan, in 1959. He received his B.S. degree in applied chemistry from Waseda University, Tokyo, Japan, in 1984 and the M.S. and Ph. D. degrees in polymer chemistry from Polytechnic University, New York, in 1987 and 1989, respectively.
In 1989, he joined the department of polymer chemistry in Yamagata University in Japan as an assistant professor and promoted to an associate professor in 1995, and to a full professor in 2002.
His work has been recognized by awards from the Society of Polymer Science, Japan, (Society Award), and the Society for Information Display, U.S.A. (Special Recognition Award and Fellow Award) in 2002 and in 2008. He also received the Herman F. Mark Technology Medal from Polytechnic University (2007) and the Medal with Purple Ribbon from Japanese Emperor (2013).