Are there 2 layers to the kindle screen?

[fallsauce]

I'm wondering how the kindle screen works.

I know the ebook needs to be refreshed each time a new screen can be shown (ie. pageflips.) But the menu, highlight, search, etc moves straight away. So is it on a layer above the ebook part of the reader?

[paperwastage]

Originally Posted by fallsauce

I'm wondering how the kindle screen works.

I know the ebook needs to be refreshed each time a new screen can be shown (ie. pageflips.) But the menu, highlight, search, etc moves straight away. So is it on a layer above the ebook part of the reader?

the purpose of a screen refresh(goes to black, then displays the stuff) is to clear away the remnants of the previous screen

for some stuff, you dont really care about clearing the entire screen(like menu loading, scrolling...) you still see some ghosting (from the previous image), but its not really a big deal

but for new page loading, you should refresh the screen to prevent ghosting, or it'll look weird

go try... open the menu, go up and down, you'll see ghosting... alt-g to manually refresh, and no ghosting

[fallsauce]

Thank you. Excellent explanation!

So is the battery usage calculated by how much stuff has changed/moved on the screen?

[TomF]

E Ink Website - How it works

[MrPLD]

Originally Posted by fallsauce

Thank you. Excellent explanation!

So is the battery usage calculated by how much stuff has changed/moved on the screen?

Battery consumption is still dominated by the underlying electronics, CPU, wifi, 3G. The screen updates tend to require very little power.

Paul.

[jphphotography]

If you disregard the wifi/3G circuitry (ie have them off) then it would stand to reason that full-screen refreshes would drain the battery more than just localized changes like the highlight feature you mentioned.

Still from what I understand of it the e-ink screen even with full page refreshes draws very little power so the difference is probably negligible. It does make me wonder though if you took two people, one who reads very fast and one who reads quite slow, I'd imagine the fast reader would drain the battery noticeably faster.

[Zerodime]

Only because he has more pageturns per time.
If the fastreader would read only the books the slowreader does, then there would be no differenze (when you disregard WLAN and 3G)

[MrPLD]

Technically the fast-reader gets a higher number of pages per battery charge - because there's a constant 'quiescent' power drain at all times when the machine is 'idle'. It's comparatively small but in the spirit of being technical it makes a difference