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Chameleon Liquid Could Replace LCDs
InvisblePinkUnicorn writes "NewScientist reports on a color-changing liquid that could cheaply replace the color components of standard LCDs. According to researchers at UC Riverside, the liquid 'contains tiny iron oxide particles coated with plastic. It is cheap and easy to make, and could also be used in flexible, rewritable, electronic paper.' From the article: 'The opposing forces of electrostatic repulsion [in the plastic] and magnetic attraction [in the iron oxide] result in the particles arranging themselves into an ordered structure, known as a colloidal "photonic crystal". The colloidal crystal reflects light because the spacing between neighboring particles in the structure is equivalent to the wavelength of light. Also, tuning the spacing slightly alters the exact wavelength, or colour, of light that is reflected. This can easily be done by varying the strength of the magnetic field applied to the crystal.'"
And it's called white-out, duh!
I'm tired of these new technologies that never make it out to the customer. Stop telling me what we could do, and do it already!
I remember having fun with powerful magnets and CRTs, does this mean LCD panels made with this new liquid be susceptible to magnetic fields too?
To do something right, you often have to roll up your sleeves and get busy.
Um, it's only fairly recently-ish we've had sub-6ms LCDs... it's funny you mention 8 ms because 8 ms is widely considered the "acceptable" gaming threshold, at least in my research when I was looking at buying an LCD a year ago or so. (Note: I held off until a couple months back, and my current display is 2 ms latency.) Not to mention, the panels on older laptop computers had significantly higher latency, and they were quite usable for basic office tasks.
Slow response time would be fine for websurfing, photo albums, PIMs, etc. The display could be used for certain PDA's, smart phones, electronic books/newspapers, etc... I think it still would be cool.
the tags are right. The brown color is not in the hue (compare with rainbow), so controlling the wavelength is not enough. You'd need to controll brightness at least, and then brown would be kind-of dark-orange.
Also, if you rely on reflecting light (aka. mirror), you rely on fact that the light source HAS this color wavelength in its spectrum. This is not always the case if you don't use sunlight.
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#\ @ ? Colonize Mars
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No, they just invented the entirely new "toner in liquid". There's no prior art and the patent is coming soon.
It sounds cute, but it's another minor advance in materials science, and a long way from being a new display technology.
The basic problem is that it requires a big array of electromagnets, one per pixel. Fabricating large arrays of electromagnets is expensive; it's hard to fabricate coils using an IC process. And it doesn't scale down well; tiny coils are tough to make. It's also hard to contain a magnetic field in a small space. So electrostatic devices, like LCDs, and emission devices, like plasma panels, tend to win out.
Previous technologies shot down by this fact include magnetic bubble and magnetic core memories. They worked, but they never got either cheap or tiny.
The variation in color around the tubes shown in the photos seem to suggest that the color is angle-dependent (not surprising given the photonic crystal design). One would see a redder (longer-wavelength) when viewing straight on to the panel than from any angle to the side. This is NOT acceptable for most applications.
I do hope they can create angle-independence -- perhaps microlenses or shaping of the cell well would help in some way.
Two wrongs don't make a right, but three lefts do.
And a magnet didn't make your CRT go all "wonky" rainbow colored?
Layne
is that they aren't susceptible to magnetic interference. With modern day TV rooms, this is essential. Even though everyone claims they have "magnetically shielded" speakers, put a few big ones close to a CRT, then tell me whether or not they are truly "magnetically shielded."
For Aiur !
\u262D = \u5350
[Fuck Beta]
o0t!
Maybe...
It just depends on how susceptible. Weren't floppy disks susceptible to being erased by magnetic interference, but people rarely took special precautions.
Yeah, because the wall behind your monitor changes all the time! Never a dull moment there!
-- Cheers!
200 micrometer is REAL BIG in lithography land. No problems there that I can see.
-- Cheers!
You're right that the change isn't instantaneous on a CRT, but the maximum refresh rate of a CRT is very much related to the decay rate of the phosphors, at least after you adjust for the marketing lies. That's why fixed-frequency 60 Hz monitors (or TVs) don't have huge flicker problems, but a multi-sync monitor with a 180 Hz maximum refresh will put you into seizures if run with a 60 Hz refresh.
In the good old days we had CRT monitors at 60Hz, and even at 50Hz and guess what? They didn't flicker! And neither does your TV!!
Nope. The phosphor is designed for that particular refresh rate.
The problems started when PCs decided they wanted to refresh at lots of different rates so the phosphor was designed for the highest rates supported by the monitor.
Result? 60Hz flickered like mad on them.
So...he's right and you're wrong. Ergo, you suck.
No sig today...
If you want a good waveform, you'll need an OLED. Those can respond in a few ms from/to any brightness level (just like an LED). Once those take off in popularity, they will probably rule the roost for gaming and video, if not everything.
"the resolution and control still isn't very good"
Looks like a glass vial to me. With a single magnet in the middle. So, yeah, resolution seems to be 1:1 and they are showing off all the colors in the vial, not trying to make it a single color. And I *do* see most colors you would need, so that's a plus.
As for liquid paper: it can be made flexible, I suppose it uses little energy and it uses reflexion as well. Couple this with high dpi and this would qualify it for digital paper in my view. Actually, for me, it would even be viable for electronic paper even without the flexible bit. I have no issue bringing a light A4/letter slab with me if it can bring up all my paperwork on request.
Well,you could put this panel on the end of some sort of tube, and have a gun of some sort emitting a focused magnetic field that swipes across the panel in an array of some sort changing the pixels one by one until it builds an image.
-Darkshadow (There was a thing called Heaven; but all the same they used to drink enormous quantities of alcohol.)
Another issue with this, which has yet to be addressed, is that the pixels in this display aren't made up of RGB subpixels. This means that when color is processed by the computer, it needs to be transmitted as a color, rather than shades of RGB. Should this technology come to market, it seems that it would be too impractical to take an RGB signal from the computer, analyze it, convert it to a color, and then display it. It would require an entirely new video driver (possibly new graphics hardware) to output a "color" signal, rather than an RGB signal.
As far as brightness is concerned, this is "easily" solved by backlighting the display with white OLEDs. This way, you have a color and a brightness, everything you need for a pixel.
Sorry, you are wrong on two counts:
a) modern LCD panels do not have a square pulse. In order to achieve fast switching times, the frame-to-frame differences are actually overdriven. Say you are currently at pixel value 100, and want to go to 150. You would actually drive the pixel at 170 or so, such that at the end of the new frame, the time-averaged transmission over the frame interval is the desired 150. The numbers are made up of course, but the principle holds.
b) CRT phosphors have a non-zero decay period, but they are actually fairly fast. So much so, that you can measure easily where the electron gun is at any given point in time. This is how light pens work (used to be the input device of choice before the mouse and touchscreens, now http://www.fastpoint.com/ seems to be the only manufacturer), or how security researchers manage to read the screen content from a reflection on the wall: http://www.cl.cam.ac.uk/~mgk25/ieee02-optical.pdf
>>Not really. It results in disappearance of the mouse cursor, and interferes with scrolling.
I guess it depend too on what you mean by "slow" response time. The OP in not so many words said it had to be fast enough to play video games without ghosting. Most applications are not that demanding.
If it was too slow you could not use a mouse or scroll, but their could be workarounds (page up and down instead of scroll, moveable focus rather than a moveable cursor).
Try this. Take your digital camera, put it into the highest ISO setting, open the aperture all the way, and take a really short exposure of a CRT screen. What you'll see is a block of scanlines (about 20 or so for a 1/1000s exposure) that is bright, and the rest of the screen, which is very dim by comparison. The transitions between the bright and the dark regions will be very sharp, which will show you that the phosphor decay is quite rapid, and you only see multiple illuminated lines because, even at 1/1000s, the exposure time is still too long to see a point.
Phosphors have an exponential decay, which means that they fall off to a fraction of their peak intensity fairly rapidly, but it takes forever for them to dim completely. That is why you see radiation in a dark room, but it is at a level that is MUCH smaller than the level you get even showing a black screen with an active electron gun.