In April 2016, Japan's Semiconductor Energy Laboratory (SEL) and Advanced Film Device announced they have developed a hybrid OLED - reflective LCD display, that can switch between an OLED mode (for dark environments) and reflective LCD mode (for sunlight visibility). Such a display could be very power efficient.

SEL TR-Hybrid display, OLED mode photoTR-Hybrid in OLED mode

SEL demonstrated a prototype display at SID 2016, and provided more information. SEL calls these displays TR-Hybrid displays (TR means Transmissive OLED and Reflective LC). To create this display, SEL introduced holes into the reflecting electrodes of a reflective LCD, and the OLED layer beneath transmitted light through these holes in OLED mode.

SEL TR-Hybrid display, reflective LCD mode photoTR-Hybrid in reflective LCD mode

The prototype screen was 4.38" in size, and had a resolution of 768x1024 (292 PPI). The display used an IGZO substrate. The aperture ratio are 76% for the LCD and 3.9% for the OLED. The drive frequency can be adaptive, so that power consumption on the reflective LCD mode can be reduced to about 1/180 when driving at 1/3 Hz (down from 60Hz in OLED mode). The contrast in OLED mode is 2850:1.

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