this is pretty exciting! i agree about the squeak-like approach. what would you use for the screen? i've been thinking that sharp's memory-in-pixel displays are the best option, but my power budget for the zorzpad is a milliwatt including screen, flash, and keyboard, not just the soc
There are ultra low power ePaper displays that only need power to change pixels but need no power to light the display or hold an image. They are usually black and white or grayscale.
> Typically, the energy required for a full switch on an E-Ink display is about 7 to 8mJ/cm2.
>The most common eInk screen takes 750 - 1800 mW during an active update
The Smalltalk-80 Alto, the Lisa and the 128K Mac had full window GUIs in black and white and desk top publishing.
The One Laptop Per Child (OLPC) had low power LCD color screens especially made for use in sunlight and would combine nicely with solar panels.
hey, i've been looking for those numbers for years! where did you get them?
the particular memory lcd i have is 35mm × 58mm, which is 20cm², so at 7½ millijoules per square cm, updating the same area of epaper would require 150 millijoules to update if it were epaper. the lcd in fact requires 50 microwatts to maintain the display. so, if it updates more than once every 50 minutes, it will use less power than the epaper display, by your numbers. (my previous estimate was 20 minutes, based on much less precise numbers.) at one frame per second it would use about a thousand times less power than epaper
so in this context epaper is ultra high power rather than ultra low power. and the olpc pixel qi lcds, excellent as they are, are even more power-hungry
pixel qi and epaper both have the advantage over the memory lcd that they support grayscale (and pixel qi supports color when the backlight is on)
