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New Display Technology to Compete with LCDs?
NetRanger writes "C|Net's News.com has a really interesting article to a new display technology that is based on interference of light patterns. The company, Iridigm, has a very compelling case for why their display method is far superior to LCD, including far brighter displays, far less power consumption... but the cool this is that the display actually works like RAM (it retains its state until voltage is applied to reset it) -- so what do you see when the driver crashes?"
Only like SRAM, not DRAM.
SRAM is pretty much static until changes are made, DRAM you'll hear described like a leaky capacitor. When you give it a charge it will slowly loose it, so you need to refresh it... many many times per second.
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This technology is great for displaying text (and pictures of butterflies) but it is very bad for games.
Look at the description of how it works. The colour is determined by the distance between glass layer and the metal plate. Big gap = red. Small gap = blue.
This is fine for static images, but it means that it takes 5 times as long for a red pixel to change state as it does a blue one.
When you have a quickly moving image, the result in severe ghosting for red objects. White objects will leave a rainbow trail - red at the far end, blue near the object. Blue objects are relatively unaffected.
If you do use this for playing Quake 3, just make sure you're on the blue team.
IANAEES....
Both SRAM and DRAM require constant power to reliably store data.
SRAM differs from DRAM because the cells that hold bits are always charged [howstuffworks has a diagram, basically its 5 logical gates in feedback]. As a result SRAM takes more power but has no refresh delays [and is bigger]
DRAM uses capacitors to store the data and requires refreshing. This makes DRAM smaller, less power instense but much slower.
For example, cache inside processors is a version of SRAM. If SRAM were as cheap as DRAM we'd be seeing 2MB caches common place nowadays...
Anyways... Peace out.
Someday, I'll have a real sig.
Actually, the hysteresis in the MEMS position suggests that a residual image might be maintained if power is lost. It just won't retain the original colors.
How can we afford to ever sleep
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Not that I'm an expert, but my guess is that the display wouldn't be affected by magnetic fields.
CRT's are sensitive because the electrons are moving with respect to the magnetic field, thus being deflected. This display works via a static charge... no way, that'll be affected by a magnetic field.
EM? well, that depends on how they build the thing... but if they know what they're doing that DEFINITELY shouldn't be a problem.
"I don't know that Atheists should be considered as citizens, nor should they be considered patriots." -George H.W. Bush
IIRC isn't this a property of Light Emitting Polymers? At least not the first incarnations, or the later revisions in that a charge is only needed to change the polymer state... so more power is used when viewing a constantly changing images (i.e. multimedia), whereas spreadsheet/office use would be on the lower end of the power scale.
Are you local? There's nothing for you here!
The company's website reports microsecond response times for their iMOD elements. Ten microseconds would support 100 FPS, which should be fine for gaming (isn't TV interlaced 50 FPS?)
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So sound again
--ebtg
Now they don't seems to have any data on framerate you can achieve or power consumption when the complete screen is refreshed frequently.
It needs a front light but only in dark environments. Apparently, the reflectivity of the surface is sufficient for normal lighted environments
How can we afford to ever sleep
So sound again
--ebtg
This is more for those that don't know :)
60Hz refresh is ok-ish in places like Australia, New Zealand and anywhere else using 50Hz mains rather than North America's 60Hz. The flicker you see on a monitor is caused by the monitor and the room's lighting interfering with each other and causing beat frequencies: very much like two musical instruments that aren't quite in tune.
Bill - aka taniwha
--
Leave others their otherness. -- Aratak
but it was good of you to think of the modulation rate based color method. BTW, did you know that modulation based color perception is a genetic trait? not all people percieve color from the spinning disk experiment. i am one that does not, and i was very frustrated when i was trying to get the experiment to work until i found out that some people are not sensitive in that way. folks in my computer club were programming their B&W monitors to show color using the technique before there were any color TV interaces.
I heard on NPR the other day an even neater sounding alternative that is about five years off.
_
It uses the fact that certain plastics when charged with electricity will emit light and certain colors. The screen would be flat and completely flexible.
Literally you would have a screen (a TV for example) that could be rolled up and put into your backpack.
Right now they are looking into small scale electronics applications of the technology in terms of putting in screens for car radios and such but they have the big plan of a flexible plastic tv or computer monitor.
Of course if you pay attention is the fact that it needs no backlighting and can be extremely thin. Very neat stuff.
_______________________________________________
ACK
repeating above, there are sub-pixels: up to 100 cells per display pixel gives ability to graduate the color.
If you'd care to look a Iridigm's website, specifically the bit about power usage, that does not seem to be the case. They give power usage for "video imagery".
Granted, they don't give a lot of detail, and the graph doesn't even have a scale... but they claim that the technology uses little power even with moving images, and there is no basis to dispute that at this time.
I would have a tough time believing that it uses more power than a CRT. Even if it does use substantially more power than they claim, it would still be well within laptop territory.
Check here
They have a Palm display side-by-side with display with their technology. (it's b&w) you canhardly see any individual pixels on their screen. Text is rather crisp, almost printed.
Why aren't you encrypting your e-mail?
will still crack and break for no apparent reason.
On the website, it's stated that since the manufacturing process is done at a low temperature, plastics can be used in a future implementation of the product. This would mean that the display would be more durable than LCD displays with glass. Currently they use glass in the manufacturing procees, probably due to the tight manufacturing integration with LCD display manufacturing, since they're trying to reduce initial costs.
If you're looking here for something insightful or thought provoking, you're probably looking in the wrong place.
SRAMs can be designed for raw speed (CPU caches) or low power (CMOS memory in old PCs before flash). High speed SRAMs can suck down a lot of power due to all of the gates and frequent logic transitions.
OTOH, The low power SRAMs intended for nonvolatile storage use all CMOS FET transistors in their logic gates. These gates draw essentially zero current unless they are actually switching.
Thus, while low power SRAMs require a voltage (typically supplied by a battery) to retain their state, they draw no current when idle. Therefore, in a technical sense, they don't actually require "power" (voltage*current) to keep their state, just a static potential.
A hydraulic analogy would be rigging two toilet flush flap valves in series, then ensuring that they never open simultaneously. This setup could store one bit (1 - open/closed, 0 - closed/open) with just static water pressure and zero flow. (A little water would flow when the valves are actually flipped.)
(btw, IAAEE)
[i]The flicker you see on a monitor is caused by the monitor and the room's lighting interfering with each other and causing beat frequencies: very much like two musical instruments that aren't quite in tune.[/i]
I usually have all the lights off when I work on a computer, and I can still see flicker whenever the refresh rate is under 85Hz. I've had cases where some unrelated change in my video driver settings caused (for whatever reason) the refresh rate to drop to 60Hz, and I had to go fix it because the flicker was bothering me so much. It has nothing to do with room lighting.
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Uh, no. Framerate in general has nothing to do with the actual display, although the image will look better if the two are in synch at some multiple.
Framerate, at least when you're talking about gaming, is how fast the game engine and graphics card can update memory. The refresh rate is how fast the electron beam is swept across a CRT. LCDs don't have refresh rates, but they do have response times And I would assume this thing would as well.
The "frame rate" on an LCD or one of these things is 1/response time.
autopr0n is like, down and stuff.
Static RAM certanly does not maintain state when the power goes out. However, it does require very little power to maintain state, and no special circuity.
SRAM is basically something like 6 transistors per bit.
DRAM, on the other hand, not only requires power to maintain state, but also requires special refresh circuitry. This is because a bit in DRAM is effectively a transistor and a tiny capacitor.
Well, the Economist article reproduced on the Iridigm website indirectly answers this question.
Iridigm's technology, which it calls an interferometric modulator, or I-mod, works by fine-tuning the gap between reflective surfaces. I-mod pixels (the dots that make up the display) are tiny paired mirrors, and the distance between these mirrors can be adjusted to one of four settings. Three of these settings correspond to the primary colours red, green and blue, from which all other colours can be constructed. The fourth is "closed", which means that no light can be reflected, and so the pixel, and thus that part of the image, is black.
Apparently, they'll be generating all colors (including white) by using RGB (plus black) combinations
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--ebtg
If SRAM were as cheap as DRAM we'd be using it for system memory and might not even need cache at all.
Not necessarily. There's an inherent slow-down associated with large address spaces. Not to mention the heat decipation. Heck, why else do we have 3 to 5 layers caching? The practical approach is to have successive layers of cheaper, larger and slower memory.
Since we already have 8 meg caches (in some high end machines), there's little value in doing away with multi-gig low-power, low-cost memories. Theoretically some apps will achieve noticable performance gains, but at enormous costs (today at least).
Furthermore, DRAM with internally managed refresh logic is functionally identical to SRAM (but non-deterministically slower). For something like video memory which regularly touches every byte of memory, the refresh logic would be unnecessary; thereby speeding up the memory. Further, DRAM is sufficiently performant enough to handle refreshes. 4MB * 80fps (for true color 1280x1024) = 320MBps. DDR can handle 2.1GBps alone. This doesn't even acknowledge the possibility of interleaving/banking/segmentation or what-ever types of tricks they may utilize.
-Michael
OLEDs are great and will take over, but the last remaining hurdle is they have a limited lifetime. Currently they put them in things like cell phones where the display isn't on all the time. The limited life is no problem there because of the intermittent use. But on a laptop, you don't want the thing wearing out (getting dimmer) quickly. They're making progress. Once they've got the thing up to a long enough lifetime the OLED display will explode. Bright as a CRT, less power and much thinner than a backlit LCD, fast response for good video, able to be put on flexible substrates, and in large quantities should be cheaper than LCD. Not bad!
Where an iMoD display wins isn't in framerate -- that's going to be driven by your graphics card, anyway -- but in the fact that it has no refresh per se, the way a CRT does. The problem with conventional CRTs is that the screen image is drawn in an essentially serial manner -- each pixel is displayed in scan line order, scan line by scan line. If you update the screen image data faster than the monitor can draw the whole image on the screen, you can wind up drawing the top part of the screen with data from frame X, the middle from frame X+1, and the bottom from frame X+2. If the screen image data is changing rapidly, the visible objects on the screen may not line up correctly across the whole frame; this is artifacting.
The iMoD display, because the pixels are addressable randomly, the same way that LCD displays are, can 'back up' to the top of the display for each frame. The pixel update time is short enough that, unlike LCD displays, you're not going to get 'trails' (and the pixels can be updated many more times per second than either an LCD or conventional monitor), and the addressing electronics can be designed to allow more than one pixel to be updated at a time, making a whole-screen update even faster, so that it's not impossible that it might be able to obtain an order-of-magnitude increase in screen redraw rate over a 60Hz (read: rock-bottom) CRT.
But the real advantage comes more from the fact that, without the screen redraw being tied to a fixed sweep rate, the actual display refresh rate can be exactly the same as the frame rate produced by your video card. With a CRT running at a refresh rate of 72Hz, no matter how many frames your video card can draw per second, you're only going to see 72 frames per second; having a video card that can draw 90 frames a second on the simple scenes only means that you can lose 18 fps due to scene complexity before you see any frame rate loss. With an iMoD display, if your video card can render 90 frames per second, you would be able to see all of them. On the other hand, since the display updates would be matched to the video card's frame rate, degradation of your frame rate due to scene complexity would be immediately visible (subject to the response of the human eye).
No.
This happens to nearly every display card in existance, it's just not always apparent since usually the screen is cleared immediately after a mode set.
This has nothing to do with static ram, it's all DRAM. The DRAM is kept valid by refresh circuitry that doesn't differentiate between memory that's being used and memory that isn't. It just refreshes all of it. So what you get is that ALL of the video memory stays put, which can be useful if you want to do page flipping, or store bitmaps offscreen in the framebuffer for faster blitting.
Most metals exist in more than one form of crystal matrix. These different types of crystals exist in almost every chunk of metal you find. You will usually end up with a small area of one form of crystal (with all atoms lined up in the same direction) which is surrounded by another form of crystal. These small areas are called grains. The smaller these grains are, the more easily the metal bends, due to the fact that the atoms on the edge of a grain do not bond well to the atoms outside the grain.
When you bend metal you tend to form more grains in it, due to the movement breaking up existing grains and splitting them into smaller pieces. The increase in grains causes the metal to weaken, even if it is a small amount every time. If the metal is allowed to "relax" for a period of time, there is the chance that two extremely close and aligned grains will convert the atoms between them into their crystaline form. This reduces the amount of grains and re-stiffens the material. This re-conversion is very slow under normal temperatures and pressures and thus is a minor effect.
You can increase the grain size and lower the number of grains by heating the metal at a certain temperature for a period of time. If you then quickly cool the metal (quench it in water, for example) you will end up with a harder material (but more brittle). This is how blades are made that hold an edge and stay sharp, the harder the blade is the better it will hold an edge. However, if you make the blade too hard then it will not bend at all and it will be brittle.
Sapere aude!
I used to work as an aquatic biologist, diving and photographing fishes from all over the globe. My photography skills are legendarily poor, but even the experts I worked with were continually frustrated with the inability of film to capture the brilliant metallic and irridescent colors we saw in person.
Alas, while it may be possible for this display technology to duplicate some of the bright colors, interference colors are usually dependant upon binocular viewing for most of their spectacular effects, and the monitor will definately be mono.
Finally, while I wish it were't so, this technology seems to be display only. I see no ready bridge to adopt this technology to CCD's or film (our two existing image capture options) or to use it directly as a capture device. More's the pity.
yep - my workmate has a cell phone (motorola, i *think*) that has an OLED display. it is BRIGHT BLUE! i thought it was vacuum florescent the first time i saw it.
Actually, that stuff's electroluminescent tape.
http://www.3dxtreme.org/pcmodstape.shtml
Not quite the same as an OLED.
Si
Coming soon - pyrogyra
Well if you had looked at the technology at their web site, the subpixels CAN'T be White. Thay can be only Black or one specific color (eg. Red). The technology has the color of each subpixel fixed by it's physical properties. (ie. it's digital, not analog) so there are red/black, green/black, blue/black subpixel types. Same idea as the old CGA displays but without the intensity bit (ie. only one bit per gun.)
Sadly, no mention on the site of how they think they play to provide any INTENSITY information.
ECL was fast, but it was just about as opposite of CMOS as you can get. It works using bipolar transistors to continually shunt large currents through resistors even when the gate is idle. That single 1K chip I worked on probably drew several of watts of power. Nevertheless, it was considered to be a SRAM.
(The mainframe CPUs put a hundred or more ECL chips on a ceramic substrate, then used the mother of all water cooled heatsinks to pull out the massive heat that was generated.)
The way the display works, I think the light would have to be reflective, not coming from the back. It appears to use the property of Iridescence.
The lighting would have to come from the side, and would reflect off the display.
One major advantage of this tech is that it should look better as the light gets brighter!
You'll have to excuse me, I was shooting from the hip and didn't realize that I had made a mistake in my original discussion.
I originally said, "When you bend metal you tend to form more grains in it, due to the movement breaking up existing grains and splitting them into smaller pieces. The increase in grains causes the metal to weaken, even if it is a small amount every time."
This is not exactly true, it had been a while since I studied metallurgy and I didn't have any reference texts to consult. To clarify, the reason the metal weakens is not that the number of grains is increasing and making the material more ductile (easily bendable), but that the dislocations (areas of stress in the metal matrix) and impurities are getting moved to the edge of the grains and are collecting together. This means that less of the metal has flaws distorting its structure and is therefore harder. Since it is harder it is now less flexible and more brittle. This causes micro cracks to form during the bending. Eventually these cracks lengthen and the metal fails.
Work hardening occurs when the metal is plasticly deformed. These deformations cause impurities and other strains to gather together and less distort the structure of the metal. Since more of the metal is ordered, it is harder than it was originally.
One thing you should know is that metallurgy is very complex. There are many factors which enter into the equation, such as grain size, alloys, impurities, many different phases (crystal structures) of the metal, etc. Often simply how the metal is composed, heated, cooled, worked can vastly change its properties.
Here are some sites to study more about metallurgy:
PLANT MATERIAL PROBLEMS - a site on metal failure
Metallurgical Terms Made Simple - a site on the basics of steel metallurgy
The Metallurgy Of Carbon Steel - a more in-depth analysis of steel metallurgy
Sapere aude!