title: High ambient-contrast-ratio display using tandem reflective liquid crystal display and organic light-emitting device.
abstract: A high ambient-contrast-ratio (A-CR) and large aperture-ratio display is conceptually demonstrated and experimentally validated by stacking a normally black reflective liquid crystal display (NB-RLCD) and an organic light-emitting device (OLED). Such a tandem device can be switched between the NB-RLCD mode and the OLED mode under bright and dark ambient light, respectively. The normally black characteristic of the RLCD also helps to boost the A-CR under OLED-mode operation. To obtain a better image quality in the RLCD mode, a bumpy and transmissive structure is used to eliminate the specular reflection and to increase the viewing angle performance that results in CR>2:1 over 55 degrees viewing cone. Besides, such a structure can also increase the external quantum efficiency of the OLED by 49.4%. In our experiments, regardless of the ambient intensity the A-CR is kept higher than 100:1.
authors.forename: Jiun-Haw
authors.initials: JH
authors.lastname: Lee
authors.forename: Xinyu
authors.initials: X
authors.lastname: Zhu
authors.forename: Yi-Hsin
authors.initials: YH
authors.lastname: Lin
authors.forename: Wing
authors.initials: W
authors.lastname: Choi
authors.forename: Tien-Chun
authors.initials: TC
authors.lastname: Lin
authors.forename: Sheng-Chih
authors.initials: SC
authors.lastname: Hsu
authors.forename: Hoang-Yan
authors.initials: HY
authors.lastname: Lin
authors.forename: Shin-Tson
authors.initials: ST
authors.lastname: Wu