What's the point of e-ink? I's good when the picture changes once in a few hours, sucks for word processing.
A monochrome transreflective LCD (without a backlight) would consume fractions of a milliwatt, can be a high resolution graphical display or character-based display, and would look plenty sharp under direct sunlight. Also widely available and inexpensive.
It can't have such a high contrast as e-ink though.
typically monochrome transflective lcds consume quite a bit more than fractions of a milliwatt, though it does depend on how big they are. the two-line reflective lcds commonly found on pocket calculators do indeed consume a fraction of a milliwatt, but power consumption scales mostly with display size
e-ink is fast enough to be usable for word processing because the updates are small and incremental and, most importantly, can tolerate some ghosting
Yeah, best compromise is a single row LCD display for the "live", "editing" line of text and then eInk for the rows of text above. Of course scrolling the eInk is still slow.
the memory-in-pixel lcd is better than that approach in every way except that it's more expensive, there's no grayscale, and the display panels don't come in large sizes
A monochrome transreflective LCD (without a backlight) would consume fractions of a milliwatt, can be a high resolution graphical display or character-based display, and would look plenty sharp under direct sunlight. Also widely available and inexpensive.
It can't have such a high contrast as e-ink though.