New low-power reflective LCD

[pdurrant]

Thanks to The Digital Reader for more news on an interesting new reflective LCD display. While it clearly is initially aimed at watches and similar devices, it can scale to ereader sized displays.

At 3mW to 4mW for a 6" display, a 3.7V, 1.9Ah battery like the one in a Kindle could power the display for 70 days or so. Of course, that's just the display, power is needed for the computer part of an ereader too, but it shows that the display is low power enough to be used in an ereader.

The displays going into production have a reflectance of 32% and a contrast ratio of 20:1

In comparison, eInk's Carta display has a reflectance of 44%, but a contrast ratio of only 15:1.

Japan Display claim 40% reflectance for their large screen prototype.

I really hope some ereader manufacturer produces a device with this display.

[Ripplinger]

Does all that mean the screen can be easily read outdoors in full sunlight the same as an e-ink screen?

[pdurrant]

Originally Posted by Ripplinger

Does all that mean the screen can be easily read outdoors in full sunlight the same as an e-ink screen?

Yes. It has no back light, it reflects light that falls on it, just like an E-Ink screen does. It does have a glass front, but it seems to be designed to be non-glare glass, rather than smooth and shiny.

It should work very well outside in full sunlight.

[Ravensknight]

2 months? Man, that is awesome!

[pdurrant]

Originally Posted by Ravensknight

2 months? Man, that is awesome!

Now, now…. I did qualify that! I would expect an actual device to have more like a two to four week battery life, like current eInk devices. The power for the computing part wasn't included in those calculations.

[drofgnal]

Now, to really get my attention also put an optional backlight on it for reading at night.

[pdurrant]

Originally Posted by drofgnal

Now, to really get my attention also put an optional backlight on it for reading at night.

I suspect that, given the way this display works, a front light as on eInk displays would be better, and poses no technical problems.

[markom]

Originally Posted by drofgnal

Now, to really get my attention also put an optional backlight on it for reading at night.

I'd rather see a very good stylus on a 10" screen.

Later they can introduce a frontlight or 13" screen.

[CRussel]

This looks promising, Paul. Especially the improved contrast. Of course, it will depend on production costs, I suspect, whether this makes it into eReaders. And how well or easily the displays scale up to eReader size.

[pdurrant]

Originally Posted by CRussel

This looks promising, Paul. Especially the improved contrast. Of course, it will depend on production costs, I suspect, whether this makes it into eReaders. And how well or easily the displays scale up to eReader size.

I'm hoping that, since it's essentially an LCD, that production costs will be low as it should be possible to produce it on existing LCD manufacturing lines. But I have no hard info about that.

I don't think there are any technical difficulties in getting eReader size displays out of the process.

[fjtorres]

Originally Posted by pdurrant

Now, now…. I did qualify that! I would expect an actual device to have more like a two to four week battery life, like current eInk devices. The power for the computing part wasn't included in those calculations.

Generally device makers trade off battery life with battery size to get cheaper and lighter devices so if the device can do 100 hours with a given battery, they'll cut back to 40 hours instead.

For a reading device matching eink battery life of 30-40 reading hours is suficient; getting color gamut and saturation well above Triton levels is the key for these displays. 5 bit color might be good enough for textbooks but they really need 12-16bit color.

[Dylrob]

What about viewing angle?

[GA Russell]

I wonder how the specs of the original post compare to the screen of a jetBook Lite. I've always been quite satisfied with that screen. Of course, the JBL screen is monochrome.

[pdurrant]

Originally Posted by GA Russell

I wonder how the specs of the original post compare to the screen of a jetBook Lite. I've always been quite satisfied with that screen. Of course, the JBL screen is monochrome.

The JBL screen has a contrast of 12:1. I couldn't find a figure on reflectance.

[Kumabjorn]

Originally Posted by markom

I'd rather see a very good stylus on a 10" screen.

Later they can introduce a frontlight or 13" screen.

Have you tested Samsung's Galaxy Note 10.1?