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Display Makers To Use Quantum Dots For Efficiency and Color Depth
ArmageddonLord writes with this news from the IEEE Spectrum, reporting on display industry gathering Display Week: "Liquid crystal displays dominate today's big, bright world of color TVs. But they're inefficient and don't produce the vibrant, richly hued images of organic light-emitting diode (OLED) screens, which are expensive to make in large sizes. Now, a handful of start-up companies aim to improve the LCD by adding quantum dots, the light-emitting semiconductor nanocrystals that shine pure colors when excited by electric current or light. When integrated into the back of LCD panels, the quantum dots promise to cut power consumption in half while generating 50 percent more colors. Quantum-dot developer Nanosys says an LCD film it developed with 3M is now being tested, and a 17-inch notebook incorporating the technology should be on shelves by year's end."
Any word on burn-in, permanent image persistence, or uneven aging? That's my main concern with OLED and Plasma.
LCD can get image persistence if it shows the same image for very long periods of time (e.g. 24 hours) but on most displays it is only temporary.
I'd be interested to hear if quantum dot might have any of these issues.
Careful with names containing L slashdot.org/~AiphaWolf_HK slashdot.org/~AlphaWoif_HK slashdot.org/~AiphaWoif_HK
Actually you're dead wrong. Quantum dots are A Thing. Here's how to make them in a basic lab: http://www.youtube.com/watch?v=bNuoYm7Su4o
You won't know how many pixels are dead until you open the box.
If you mod me down the terrorists will have won
A pure color is light with a narrow spectral bandwidth. It doesn't matter which color, just that there is ONLY that color.
Color != Frequency. They always put that color chart under frequency, but it's rather misleading. Colors are the response of our three types of cones to a particular spectrum of light.
-- Let us endeavor so to live that when we pass even the undertaker shall be sorry. -- M. Twain
Because the energy levels of the electrons are at quantum levels. They transition between these levels and emit light. This is an absolutely correct usage of the word "quantum". You are a foolish troll.
Oh, and even if what you were saying was true, it wouldn't really change the resolution at all. That's not how sampling works. If your display is 1024*768, you have that many pixels. Making it so each pixel can show any color wouldn't really increase the resolution. Your ability to resolve spatial changes in color is lower than in intensity. So adding "color spatial resolution" is not equivalent to adding "intensity spatial resolution" - this is why many encoding schemes use more bits for intensity than color information - it's more efficient.
-- Let us endeavor so to live that when we pass even the undertaker shall be sorry. -- M. Twain
The whole field of computing is built on three-primary color specification anyway. Either RGB, or HSV, or YUV, or some varient of them. Or CMYK, in which the K is really a fudge-factor used to account for real inks not behaving like mathematically ideal inks. So even if someone built a display of a wider gamut, good luck finding any content to use it. I suspect this is just marketing being allowed to write the press report.
Perhaps because they're semiconductor particles whose electronic properties are size-determined due to quantum confinement, rather than bulk material properties.
They mean "we need funding and investors, and 50% more sounds great without actually saying anything".
Seven puppies were harmed during the making of this post.
If you're going to call somebody out for being wrong, you might want to actually do some research. Those 1024x768 pixels are made up of basically triple that in terms of red, green and blue sites that emit the actual light. If you replace those with ones that can handle the entire gamut you would need a third of them and you lose the overhead from having to have individual shutters on each one.
Well, yes and no the chart is technically not wrong if you have a single frequency light source like a laser. The trouble is that most real world objects emit a spectrum of light. This chart shows the cone response relative to frequency so the cone's response is an integral over the spectrum*sensitivity. The problem is that in all commonly current display technologies (CRT, LCD, LED, OLED, 3-chip DLP) you only have a fixed number of frequencies to work with. For example say you have red (600nm), green (540nm) and blue (440nm). Well, it turns out you can't actually produce all combinations with just three wavelengths as real world objects do with infinite wavelengths.
The reason for this if you look at the response chart is that the curves overlap, you can't simply decompose them into three components you can set individually. Any wavelength you send to stimulate the M cones also stimulate the S or L cones. And our vision is particularly good at picking up on those differences, it's a two-stage process like illustrated here. Even if the mix in the SML cones is mostly right the Cg and Cb cells are extremely good at picking up on differences in the relative mix. Ideally you'd like more wavelengths or white light + a color wheel like used in single chip DLP, but it's not that easy and you need a signal with the extended information like xvYCC.
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Fully saturated, i.e. a single wavelength, as a laser produces.
The color filters of LCD panels let through a narrow but not-single-wavelength bandwidth of color. This restricts the color gamut you can reproduce. As explained in TFA.
Wonder what the public key field is for?
" beautiful displays that would be inexpensive and easy to manufacture."
But expensive to buy for sure. And will only be slightly cheaper when the next superior tech is at the door. Rinse and repeat...
Which would then give you enough space to triple the resolution (which may be what the GGP was driving at) or, if not, would increase sharpness in any case. As demonstrated by the effectiveness of Cleartype, RGB subsampling does have an impact on perceived resolution, and RGB subpixel techniques can be applied to colour images as well as text.
systemd is Roko's Basilisk.
The term is related to Quantum Well and Quantum Wire. A quantum well is a system where particles (electrons) are confined to move in 2D by two very large potential barriers on either side of the well. It's generally one of the first systems studied in quantum mechanics. Quantum wires are like quantum wells except the potential barriers also exist in a second dimension, so that the particle is confined to move in 1D along the "wire". A quantum dot is a small box which is confined by potential barriers in all directions so that the electron can only exist within the extremely small dot.
Obviously quantum dots are going to be around the nm range so that they can actually confine the particles in any meaningful sense, but the point is the effects that QM predicts for that particular configuration. The size and shape of the dot allows us to precisely tweak the energy levels and wavefunction symmetries involved, something fairly particular to the "nano 3D potential barrier" system.
The whole field of computing is built on three-primary color specification anyway. Either RGB, or HSV, or YUV, or some varient of them. Or CMYK, in which the K is really a fudge-factor used to account for real inks not behaving like mathematically ideal inks. So even if someone built a display of a wider gamut, good luck finding any content to use it. I suspect this is just marketing being allowed to write the press report.
RGB has nothing to do with computing, but everything to do with the physics of light. Printing uses CMYK also because of the physics of light. The difference is RGB is when light is emmitted and CMYK when it is reflected. That is why blue and yellow paint make green, but blue and yellow light make magenta. With light, mixing colors is additive, with painting/printing, it is subtractive.
Apparently from all the other posts, the 16.7M colors we can get now do not overlap 100% with the 10M colors we can see. I believe this is called the Gamut range of colors being produced vs the Gamut we can see.
Supposedly these light emitters can create a Gamut of light frequencies (colors) that overlaps more, thus can produce more colors (that we can see).
A fool throws a stone into a well and a thousand sages can not remove it.
RGB were the chosen wavelengths only because by mixing them in appropriate ratios it is possible to reproduce the perception of most colors to human vision. If there were any non-humans animals smart enough to judge, they'd tell you that all the colors on television look wrong. Humans see subjective colors, not spectrographs. To represent a color with precision would require storing the entire spectrum, which is impractical.
The mathematics of CMYK say that f you have full use of C, M and Y all absorbing you should get nothing reflecting at all - pure black. But real inks don't work quite like that, they reflect a little light even in regions of the spectrum the user would rather they didn't, so what you'd actually get is a murky blackish-brown. That's why the extra K: The additional black allows for the imperfect nature of ink to be corrected for.
Single frequency peak. That is a pure colour. When you look at a typical incandescent light it is a broadband signal spread across the visible range and well into infrared (hence their inefficient at lighting a room despite being very efficient way of converting electrical energy into photons). For an LCD displaying pure red the peaks actually look rather fat around the red with minor peaks in the green and blue range as well as the backlight bleeding through the display. These imperfections is what makes the primary colours not pure and is also the reason the LCDs can't display black.
A fully saturated colour on your display is not a fully saturated colour. For comparison take a green LED and try and generate the same colour visually in photoshop. It can't be done on an LCD display. Really high end displays do come close in the red and blue areas though.
Pure colours are those emitted by single peak sources. Lasers and diodes are are good example as the energy of the photons emitted is related to the bandgap in the semiconductor and thus is quite well controlled and of a single frequency.
To visualise this on a graphic take a look at this: https://upload.wikimedia.org/wikipedia/commons/thumb/6/60/Cie_Chart_with_sRGB_gamut_by_spigget.png/537px-Cie_Chart_with_sRGB_gamut_by_spigget.png The CIE diagram displays the visual range of colours the human eye can perceive. It's stretched to represent our enhanced sensitivity to greens. Points along the outside edge of the diagram represent pure single frequency colours. The point with the temperatures in Kelvin represent black body sources like the sun which are broadband. Finally the sRGB triangle is formed by the three primary colours which match 99.9% of the LCDs on the market. As you can see our standard displays cover less than half of the visible range of colours.
I measured an OLED display with a spectrometer once. The three peaks were right at the edges of the horseshoe at 460nm, 530nm, and 620nm. Not perfect coverage for the human eye but still amazingly better than what most monitors can do.
Because the gamut of 24-bit RGB doesn't cover the entire range of visible colors and intensities. While we can only distinguish ~ 8M colors, we can distinguish a huge range of intensities. 24-bit displays cover 16M colors AND intensities, so in this case, 16M is not > 8M because they're counting different things.
While current displays are adequate for most purposes, they do not display all of the colors we can see, nor all the intensities we can see. Typical displays only cover 45%-75% of the AdobeRGB (1998) color-space, which itself is a subset of the visible gamut. Some (more expensive) displays cover a greater percentage of the visible range, but none cover the entire range.
make imaginary.friends COUNT=100 VISIBLE=false
I don't care about colors or power savings. Get me better DPI or just more pixels overall.