Japanese display manufacturer The Semiconductor Energy Laboratory (SEL) developed a 4.38-inch hybrid display that combines OLED and LCD technologies together to create high contrast and color quality indoors, according to a Nikkei Technology and EE Times report.
During the latest SID conference, the research lab displayed its TR-Hybrid Display, where the T stands for transmissive OLED and R for reflective LCD.
The Nikkei Technology reported covered how the two displays were physically intertwined to enable the screen to swap from one mode to another. The OLED part of the display is positioned at the back of a reflective LCD, and its emitted light is transmitted through holes that are cut in part of the reflecting electrodes. The reflective LCD and OLED displays are driven independently, with respective aperture ratios of 76% and 3.9%.
The production technology for the display involves SEL using a delamination technology for flexible OLED displays by applying a peeling layer to the glass substrate for carriage, and TFTs are formed on top of it, according to the report. Bottom-emission OLED devices are formed to extract light to the TFT side and covered with a flattening film, and a glass plate put on top of it.
Afterwards, the peeling layer is detached, and the glass substrate is removed. Lastly, a color filter substrate is attached to the TFT side (without the glass substrate), and a liquid crystal material is injected.
The screen size, pixel count and resolution of the prototype display is 4.38-inches, 768 x 1,024 and 292ppi, respectively. For further details please see the Nikkei report.