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Samsung and LG Unveil 8K TVs (cnet.com)
The latest TV "must have" that you actually don't really need -- at least right now -- has arrived at the IFA electronics show in Berlin. That's 8K, the super-crisp display technology that has four times the resolution of 4K screens. CNET: Samsung on Thursday showed off the Q900, which packs in more than 33 million pixels. The 85-inch TV will be the first 8K TV to hit the US market when it goes on sale in October, although Samsung didn't specify the price. Its arch rival LG a day earlier announced what it called "the world's first" 8K OLED TV. It showed the 88-inch device to some reporters in January at CES but didn't specify when there would be an actual product for consumers. Meanwhile Sharp began shipping the LV-70X500E 70-inch 8K monitor earlier this year to Europe after launching it in late 2017 in China, Japan and Taiwan. 8K TVs dramatically boost the number of pixels in the displays, which the companies say will make pictures sharper on bigger screens. "We ⦠are confident that [consumers] will experience nothing short of brilliance in color, clarity and sound from our new 8K-capable models," Jongsuk Chu, the senior vice president of Samsung's Visual Display Business, said in a press release.
So what's the incentive to buy one of these things if the content world is pretty much still on 1080i/p, let alone 4k?
Jagged font edges can be "fixed" by anti-aliasing. Your brain is incredibly good at making up details that aren't there if it helps it make better sense of what it's seeing. So if it sees what looks like the smooth curve of the letter O, then it will see a smooth curve even if it's actually made up of different-brightness dots. The illusion is only broken when other info (non-aliased pixels) makes it obvious that the curve isn't smooth.
If you don't believe anti-aliasing fixes it, then prepare to have your mind blown. Every TV image you've seen has been displayed at non-native resolution. When you watch a 1920x1080 TV, you're actually only seeing about 1890x1060 pixels. For obscure historical reasons, TVs overscan the video image. So if a show is recorded at 1920x1080, the image that's displayed on your 19201080 TV is actually a crop of the center portion of the original image, enlarged to fit the 1920x1080 pixels of your TV screen. That breaks the 1:1 correspondence between image pixels and display pixels. But it's fixed by anti-aliasing. Usually bicubic interpolation, although lately Lanczos has been becoming more popular (it's more processor intensive, but processing power is cheap nowadays). So every TV image you've seen since we moved to digital TVs has had jaggies, they're just hidden from view by good anti-aliasing.
The real problem with modern displays is that the pixels are square. Pixels aren't supposed to be square. They're supposed to represent an infinitesimally small point, so the most accurate representation is a round blob called a point spread function. Brightest (greatest representation of the pixel's color) in the center, with the edges fading out (color info mixing with that of adjacent pixels). This is actually how the old CRT monitors and TVs displayed pixels, which is why you could use them to display any screen resolution.
But modern displays typically use a LCD grid with fixed-sized square pixels. Those squares add nonexistent information to each pixel (the sharp edges and the corners). This extraneous information makes the display appear sharper when displaying perfectly vertical or horizontal lines. But that sharpness is an illusion, and you pay the price in jaggies whenever displaying anything that's not perfectly vertical or horizontal. It also doesn't work when the underlying pixel grid of the image doesn't fall exactly on the physical pixel grid of the monitor. Which is why LCD monitors look fuzzy when displaying a non-native resolution which isn't divided by an integer multiple (which are the only resolutions which maintain the correspondence between image pixel edges and display pixel edges).
Anti-aliasing can help, but it's just a band-aid rather than a real fix. Moving to higher resolutions makes the band-aid less noticeable, and from a technical standpoint may be easier than a true fix (which I'm not sure can even be done with LCDs or even OLEDs). I use a 1080p projector to display a 150" image. And the reason I'm anxious to move up to a 4k projector is that I can actually see the pixel grid. It's easy to zone out and ignore it when watching a movie, but every now and then I notice it and it becomes annoying.
There actually is a good reason not to be annoyed by this resolution race. Holograms require about 1500 dots per mm. So an 8192x4096 display would actually be sufficient to generate holograms if you were able to shrink the display down to 5mm x 3mm. I figure in 20-40 years, display technology and GPU technology will have advanced enough to generate real-time holographic displays.