Boffin builds better display from... a cuttlefish
Ultra low-power reflective display
Cuttlefish have inspired boffins from the Massachusetts Institute of Technology (MIT) to develop a screen that uses less than one-hundredth the power of an LCD TV.
The mollusc’s ability to change its skin colour extremely quickly prompted Edwin Thomas, an MIT professor, to create a prototype screen that displays images by reflecting light – rather than creating it.
As a result, Thomas’ screen only uses a few volts of electricity. Admittedly, though, the display only measures several square inches but it's just one micron – one millionth of a metre – thick.
It consists of up to 30 alternating layers of polystyrene and poly-2 vinyl – a conductive material that expands between the polystyrene layers when a voltage is applied to it.
Changing its thickness changes the wavelengths of the light it reflects. Non-visible wavelengths, such as ultraviolet, can also be reflected, given the right thickness of material.
But Stephen Foulger, a professor at Clemson University in North America, told website Discovery that such screens have a limited viewing angle and can only be used in a well lit areas.
So you may never see a TV based on this technology, but it has the potential to be used in electronic ink-based gadgets and on billboards. Thomas said he also hopes to build a self-assembly kit for use by children in chemistry classes. ®
COMMENTS
@TeeCee
LMAO I cant get the image outta my head!
(Also a bird owner, but a cockatoo is just plain destructive, and likes to corner the dog too ;-)
@Greg Fleming
"Voltage by itself is meaningless. Power consumed is derived from Ohm's law:
P = {V x I} / R or P = {V² / R}"
Ignoring the niceties of the possible complex nature of the waveforms involved you might find that.....
Power
P = V x I
Ohms law
V = I x R
=>
P = I x R x I
P = I^2.R
and
V = I x R
=>
I = V/R
=>
P = (V x V)/R
P = V^2/R
"Of course, scientific rigour these days ... I'll get my coat"
That will be the one with the crib sheet still in the pocket then?
Roll up, roll up!
Get your invisible clothes and tanks here :)
Not a reflective LCD.
The clue is in the multiple layers business. LCD's only need 1 layer but the light *needs* to be polarised. This is the *real* PITA of the technology. All large area light sources, fluorescent, electroluminescent etc produce un-polarised light so lose a load (30% from memory) of light emitted. A large area flat souce whose light output was polarised by *default* rather than filtered, would be impressive.
This thing appears to be a real time variable Fabry-Perot filter. Typically passive versions (multi-layer mirrors) are swivelled to change the lengths of the light paths between the layers to permit transmission or reflection. This switches path length *without* physical movement and *without* needing polarisation.
IIRC these filters are normally used for narrow band filtering so its Achilles heel may be its optical bandwidth, along with viewing angle. The bandwidth is not necessarily a killer for a display (EG Green is 550nm +/- 10nm instead of a broad hump) but a narrow viewing angle, given the large progress in this area, would probably kill it as a display. But for printing, projection or some kind of optical image processing so what.
and just to drive the point home, amazing science
Citing the Discovery article:
"The screen is so easy to assemble, said Thomas, that he that is working with a Boston area science teacher to produce a version cheap enough, safe enough and simple enough for middle and high school students to build in chemistry class."
I am going to completely and utterly ignore all the "ohnoz, volts instead of watts!" people and instead be amazed at display technology that school children will be able to make as a not-even-science-project. Trivialisation? Please, yes, as soon as humanly possible, I want reflective full spectrum colour displays to be something anyone can whip up over a couple of hours instead of having to trust the big tech players to make what they think we will buy by making it just far away enough from what we actually want =(
