General > General Technical Chat
what are monochrome 4K-LCDs used for?
<< < (4/4)
helius:
Subpixel rendering is only useful for bitonal objects like fonts (and most implementations only support fonts).
tooki:

--- Quote from: NiHaoMike on March 21, 2020, 12:31:55 am ---
--- Quote from: tooki on March 20, 2020, 01:26:41 pm ---Ugh, I hope this doesn’t become popular until the technology allows for extremely fast rates like 1000Hz. I am sensitive to flicker, and I can spot a DLP projector from a mile away when it’s a mostly dark background with a few bright objects, as the famous rainbow effect.

--- End quote ---
That's exactly why it has not caught on. I'm not sure why so far, nobody has tried that in a device that's primarily monochrome with colors mostly just for minor things like accents, for example, an ebook reader. (The tablet tried to be a normal tablet with "eink mode".)

--- End quote ---
How would that make any difference? It's not motion in the image that causes the rainbow effect, it's eye movements of the viewer.

I mean, you could use very fast backlight pulsing to change the backlight color of an e-reader, but what use is that, or rather, what about that wouldn't be achievable with regular LED backlighting, just with RGB LEDs or various shades of white, if it's just adjusting the color temperature.



--- Quote from: Circlotron on March 21, 2020, 02:17:53 am ---You could say a 4K lcd actually has 12K horizontal pixels whereas a monochrome one would only have 4K. Wouldn’t the colour one give better resolution if it used sub pixel rendering?

--- End quote ---
In theory, yes. But it comes with its own tradeoffs, like the fact that white areas have three times as many gaps in them as a monochrome LCD would.


--- Quote from: helius on March 21, 2020, 05:35:56 am ---Subpixel rendering is only useful for bitonal objects like fonts (and most implementations only support fonts).

--- End quote ---
There's no reason for it to apply only to bitonal things — if anything, it only really works well for things that have variations in brightness, which is why we invariably apply subpixel rendering to antialiased font rendering, not bitonal rendering. Without the antialiasing, the color fringing is too distracting.

Most implementations of subpixel rendering are very limited in where they can apply, insofar as I don't know of any that are applied to anything but text, and many of those only apply it to text on white or black backgrounds. But it works beautifully on color backgrounds, too, and there's no reason it couldn't be applied to complex backgrounds*. I suspect that if high-resolution (as in, pixel density) displays hadn't become available, we might have invested the effort to make our graphics drawing engines perform subpixel rendering on everything. But with the high-res displays with pixels so small as to be invisible becoming commonplace (and many of them using complex nonuniform subpixel arrangements), it became easier to simply brute force it in hardware.

*and this can be tested by taking subpixel-rendered text on a white background, and then photoshopping that onto an arbitrary background image. The result is actually flawless. (At least, in my experiments of essentially using it as subpixel "ink" onto a light background. I haven't tried anything where the text is lighter than the background.)
jogri:

--- Quote from: amyk on March 21, 2020, 01:39:28 am ---Eizo makes a bunch of them for medical applications. Prices are in the 4-5 figure range.

--- End quote ---

Those are used for viewing X-ray images, they even need to be calibrated every so often to make sure the colour tones are exactly right as the difference between healthy tissue and a tumor can be hard to see (remember, we are talking about differences in density), especially with small tumors.

If you see them on sale on ebay etc they probably failed the test/calibration.
SiliconWizard:

--- Quote from: Circlotron on March 21, 2020, 02:17:53 am ---You could say a 4K lcd actually has 12K horizontal pixels whereas a monochrome one would only have 4K. Wouldn’t the colour one give better resolution if it used sub pixel rendering?

--- End quote ---

Nah. The spatially distributed RGB dots will always make the image look a little fuzzier. If you want to look at grayscale images only, you can't beat a purely grayscale panel IMO.
Besides, given they are simpler to design, they may also have better luminance resolution (that's why I was asking for bit depth). A typical RGB panel has 6 to 8 bits per individual dot, the grayscale panels may have more (although I'd like to see specs!)
Miyuki:
EIZO medical monochrome panels have up to 14-bit tones it is way more than conventional ones
Navigation
Message Index
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod