Daylight Computer Company and the definition of electronic paper

Can Live Paper be accurately categorised as electronic paper?

Daylight Computer Company markets Live Paper (an adapted Transflective LCD technology) as electronic paper - in their words, it is like E Ink but better. This opens the question: What is electronic paper? Are there characteristics that define a display as electronic paper? Can Live Paper be classified as an electronic paper solution?

A case of false advertising?

Daylight Computer Company is not using false advertising when it likens Live Paper to E Ink. Rather, it is a question of definition. Daylight has a minimalist understanding of electronic paper, including any display technology requiring no internal light source. While Daylight’s tablet (DC-1) has a backlight that can be turned on when needed, it can operate without one activated. Thus, based on this minimalist definition, Live Paper falls under electronic paper, reflecting external light like a printed page.

Other definitions of e-paper are more stringent, including insensitivity to external lighting conditions and bistability, i.e., the ability to sustain an image without needing an external power source. Bistable technologies include electrophoretic (e.g., E Ink), Electrowetting, Interferometric modulator (Mirasol), cholesteric liquid-crystal (ChLCD) and Electrochromic displays. RLCD and Transflective LCD can operate without an internal light source but still rely on a power source to maintain an image.

External lighting conditions also affect the level of darkness and viewing angles of RLCD and Transflective LCDs. For example, HannsNote 2 (a colour RLCD e-note) requires an environmental brightness above 500 Lux, with 800 to 1500 Lux suggested for reading.

Why is Daylight Computer Company signalling E Ink? Due to its E Ink’s prominence in the e-paper space, Daylight is attempting to give DC-1 a unique selling point. The idea is simple: Live Paper has the refresh rates of a regular LCD while being eye-friendly and power-efficient (compared to emissive display technologies). Technically, DC-1 does share similarities with E Ink, even if its transflective LCD screen is a different display technology.

Is Transflective LCD better than E Ink?

Whether a Transflective LCD is better than E Ink is a question of application. The positives of a Transflective LCD like Live Paper include interactive fluidity and content streaming. These benefits are use cases that will define whether the positives of a Transflective LCD are worth the trade-offs of a dimmer screen, poorer viewing angles and higher power consumption.

Another factor is cost. The lower volumes produced and higher manufacturing cost means RLCD and Transflective LCDs will cost more than E Ink. For example, DC-1 costs nearly twice that of Onyx BOOX Go 10.3.