*Transparent* E-Paper at Purdue University

[NatCh]

Nanotechnology yields nanotransistors and nanowires, and e-paper you can see through!

The folks over at Purdue University have decided not to let the uber-geeks from MIT have all the e-print fun. They've created an entirely transparent e-paper.

(Please note that the image here isn't the stuff -- the uber-geeks at Purdue haven't provided any actual images, so I had to make due)

The first image that flashes to my mind is this stuff, over a white background, with a back-light behind that, or maybe in between.

The first things that popped into their minds, evidently, included: "e-paper and flexible color screens for consumer electronics to 'smart cards' and 'heads-up' displays in auto windshields."

Most of the linked write up is recapitulation of the advantages of e-papers vis a vis conventional display techs, plus discussion of how previous approaches failed to yield fully transparent results. And a fair amount of disjointed exuberance over what they've done -- arguably well earned exuberance.

You can get the gist of what they've accomplished from the study's Abstract:

ABSTRACT

Fabrication of Fully Transparent Nanowire Transistors for Transparent and Flexible Electronics

SANGHYUN JU1, ANTONIO FACCHETTI 3, YI XUAN1, JUN LIU3, FUMIAKI ISHIKAWA2, PEIDE YE1, CHONGWU ZHOU2, TOBIN J. MARKS 3*AND DAVID B. JANES 1*
1School of Electrical and Computer Engineering, and Birck Nanotechnology Center, Purdue University; 2Department of Electrical Engineering, University of Southern California; 3Department of Chemistry and the Materials Research Center, and the Institute for Nanoelectronics and Computing, Northwestern University

In this study, the authors have demonstrated fully-transparent thin-film transistors (TFTs) on both glass and flexible plastic substrates. The TFTs utilize wide-bandgap semiconductor nanowires as the active channels, and transparent conducting oxides for the gate, source and drain electrodes. The transistors exhibit good performance characteristics, including relatively high on currents (up to 10 microamps per nanowire) and high on/off current ratios (required for digital applications in order to achieve low power operation).

For those who want as much detail as they can get, here's the full article.



A special thanks to "The Watcher" over at the Baen Bar for pointing this out!

[orcinus]

Goody! Now we can have it backlit too

[mogui]

Uh. Wouldn't that be e-Saran Wrap?

Actually I have been hoping for eTissue so I can read while attending the, er, cabinet.

Sorry for the in-joke.

[NatCh]

You should be sorry, mogui!

I should have pointed out that this stuff is still very much at the laboratory stage, though with e-ink displaying some market viability, they may be more ... motivated to bring it out of the lab than they might have otherwise been.

[Adam B.]

Very, Very, cool.

I agree that a whilte background + backlight would be ideal. I don't know how the technology works, but I like the idea.

[NatCh]

It just occurred to me -- the sort of thing they're describing might also make the old sci-fi idea of windows that you can black out without blinds or curtains possible! I've always loved that idea.

[yvanleterrible]

Originally Posted by NatCh

It just occurred to me -- the sort of thing they're describing might also make the old sci-fi idea of windows that you can black out without blinds or curtains possible! I've always loved that idea.

It does exist; LCD based. Cadillac had a proto of an automatic windshield that varies the opacity according to incoming light.

[NatCh]

But ... doesn't that stuff have to be continuously powered?

I'm thinking I'd like opaquing windows on my house, and I wouldn't want them to go all clear when the power went out. Nor would I want them drawing power all the time, if I can help it.

[yvanleterrible]

True eink would be better. LCDs of this kind take relatively low amounts of power and outages being fairly unfrequent, I don't think the family jewels would be exposed that often. Just make sure to have a bathrobe at hand!

[dugbug]

I get the impression that their "epaper" is simply the transparent film over an opaque white background. So maybe theirs would have nice strong white but weak on black.

[NatCh]

That's a thought, dugbug, they haven't specified there the mechanism for the 'ink' itself, and how opaque and black it can be is definitely an important factor.

[orcinus]

Originally Posted by yvanleterrible

It does exist; LCD based. Cadillac had a proto of an automatic windshield that varies the opacity according to incoming light.

Not just a proto. There were commercial models (other marks, Saab among them, i think, or Volvo) with LC-based window tinting. Also, a lot of cars today use LC's to auto-tint the central rear-view mirror when someone driving behind you hits it with high beams.

There were also some house windows mentioned installed somewhere (again, can't remember where ) and i recall reading about a prototype window containing both, a transparent photovoltaic layer and an LC layer, sandwiched between the glass panes.

On a side note, transparent e-paper could create some interesting new possibilities for user interfaces... Stacking sheets with annotation on sheets with content, for example (in a "dumb" way, like overhead transparencies, or with some imbued "intelligence", i.e. sheets "sensing" one another's content and position).

[NatCh]

Originally Posted by orcinus

Also, a lot of cars today use LC's to auto-tint the central rear-view mirror when someone driving behind you hits it with high beams.

I hadn't realized those were LC based!

Originally Posted by orcinus

On a side note, transparent e-paper could create some interesting new possibilities for user interfaces... Stacking sheets....

Great googley moogley. I think you just invented a true 3D display, orcinus.

[orcinus]

Originally Posted by NatCh

I hadn't realized those were LC based!

I think they are. If they aren't, what do they use?

Originally Posted by NatCh

Great googley mooogley. I think you just invented a true 3D display, orcinus.

Egads! Great idea! A BLOCK of transparent e-paper!

(BTW, too much Zappa? )

[yvanleterrible]

Originally Posted by orcinus

I think they are. If they aren't, what do they use?



Egads! Great idea! A BLOCK of transparent e-paper!

(BTW, too much Zappa? )

Frank!?! I love that guy's music. Vai's taken over you can still feel Frank's presence in his music. That must be from the years he put in with the 'Mothers'.

Great Googely Moogely was as exclamation on 'Yellow Snow' wasn't it?

BTTT I still don't understand how eink could be made transparent!