Samsung to use Sub-Pixel VGA Screens

pdawerks writes "Samsung Electronics has developed a new graphics chip that will allow half VGA screens to produce VGA resolution. The novelty is specially aimed at future mobiles with VGA screens that will be less than 2.4 inches. It generates color using an entirely new driving method called sub-pixel unit driving methodology." Not sure if I think it is exactly new or not, but it's nifty.

Comments

More Information

[Temporal Outcast]

More details can be found at Deisgntechnica.

Geekzone also has a similar article.

Re:More Information

[Stanhenge]

Refer to the patent US#5193008 for a technique that increases resolution of a raster device.

DP-Tek developed this for laser printer devices, but the idea applies to other technologies. Basically, you can place a physical line between adjacent laser scan lines, using the analog memory of the OPC drum.

MS Cleartype

[darkmeridian]

The article is really short, but it says that the screen will use sub-pixel technology to allow a half-VGA screen to render VGA resolution. MS Cleartype also uses sub-pixel technology, though to make text sharper.

A linkie with information about sub-pixels in general (though it's on grc.com, whatever.) http://grc.com/cleartype.htm

Re:Sounds Like Interlacing?

[DeepFried]

Interlacing does not double lines. It is just a process that brings the lines up in an alternating (odd/even) sequence. This is now being joined by progressive scan which brings the lines on in order from top to bottom.

Progressive or interlaced, can each scale in lines of resolution to HiDef. 1080i and 720p respectively. (i=interlaced p=progressive)

Interlacing is used to reduce flicker

[GillBates0]

and does not have anything to do with the resolution. Infact, interlacing is sometimes called "interlace scanning", because the gun in the CRT draws alternate lines across the screen to reduce the visible flicker arising due to the time required to move the gun from top to bottom.

As usual, Wikipedia has a good article. To quote:

Interlacing is a method of displaying images on a raster-scanned display, such as a cathode ray tube (CRT), that results in less visible flickering than non-interlaced methods. The display draws first the even-numbered lines, then the odd numbered lines of each picture.

Re:Interlacing is used to reduce flicker

[shirai]

Interlacing is used to reduce flickering? I think not. It used to be used to reduce *bandwidth*.

An interlaced image refreshing at 60Hz (30 full fields per second divided by 2) is going to have the same flicker as a non-interlaced image refreshing at 60Hz.

This is actually a very complex subject to do with how people view images, resolution vs fields per second, what type of images you are viewing, movement vs. still images, etc. but in terms of reducing flicker, I would say, at the very least, the statement is deceptive.

In fact, one of the major problems with old Amigas running in interlaced mode was the annoying (you got it) flicker. This is because a horizontal line that was exactly 1 pixel would turn on and off every 60th of a second. So in this case, it would depend on how you defined the world flicker too.

To be fair, I think what you meant to say was that given the same bandwidth on a non-digitally compressed transmission and without digitally upconverting the signal, you can get 60 fields per second (at 30 frames per second) instead of 30 fields per second (at 30 frames per second) meaning that you will probably get less inter-frame flicker. But even this is deceptive because if you built televisions specifically for 30 frames per second, you could simply reformulate the glow on the screen to last an extra 1/60th of a second longer. But perhaps this is (a) hard to do and (b) back then they wanted the extra fields per second for smoother motion. By the way, a lot of the bandwidth savings doesn't apply to digital due to the way that digital compression works. This was a controversial point during the discussions on HDTV resolutions.

Fudge. I'm trying to cover all my bases here so I don't get flamed for not knowing what I'm talking about. Suffice it to say, interlacing and reduction of flicker do NOT walk hand in hand. It is simply one factor, of many, that comes into play.

Re:Interlacing is used to reduce flicker

[Anonymous Coward]

>Suffice it to say, interlacing and reduction of flicker do NOT walk hand in hand.

When the TV was invented, it was noticed that a phosphor did not remain lit long enough for the beam to make a complete pass at 29.9fps, therefore there would be significant "flicker" in the picture. The inventor(s) decided to interlace so you'd get a more uniform brighness to the picture and eliminate the flicker. This problem has long since been solved in other ways.

During the VGA days, however, the reasons were entirely different, as you suggest.

Re:Interlacing is used to reduce flicker

[mercuryresearch]

Parent reply post is on the mark here.

Where the confusion comes up is in the old days where interlacing was first used -- black and white television. Interlaced TV signals drove black and white CRTs... and by selecting the right phosphor, the displays had persistence, where the image would continue to glow into the next frame even after being drawn. High persistance phosphor DID cut down on flicker, and was necessary because of the interlacing.

If you want to get into really obscure stuff... Radar display tubes (and some oscilloscopes) often had incredible persistence -- often lasting several to even tens of seconds. Surplus radar tubes were popular among ham radio operators doing slow-scan television, as they could maintain the TV display at the insanely low frame rates used at the time (I think it was about 1 frame per 8 seconds or so, memory is hazy here.)

Anyway, think of the displays long ago as a giant analog visual low-pass filter -- you could throw pretty much any signal at them regarless of flicker and get a flicker-free display, so the bandwidth savings from interlacing was an obvious choice. Not so with digital technology today.

Re:READ THE DAMN ARTICLE

[Greger47]

Err, why? It's the same thing as ClearType, they just rotated the display 90 degrees and are doing subpixles vertically instead of horizontally.

My guess is that someone read that MS patent really carefully and concluded that it only covers horizontal subpixels. :)

The novelty would be that it's implemented in the display driver chip thus I guess it can move any pixel around, not only when rendering fonts.

/greger

Article missing critical technical information

[francisew]

Here is a link to the Samsung website about the technology: http://www.samsung.com/Products/TFTLCD/Technology/ 4colorrandering.htm

I wouldn't complain too hard about the confusion in the details. They couldn't even spell 'rendering' right on their own site (4 color randering???).

It also discusses 'physicail' pixels. I dunno about that.

They seem to have created smaller pixels, which are spatially located across a different area than normal.

They then need fewer wires to connect the given number of pixels. Meaning a higher resolution with fewer interconnects. Maybe I'm completely wrong in this 1 minutes evaluation.

The neat thing is the overlap of their 'logical' pixel arrangements. It would seem they are using traditional dithering with a complicated arrangement of pixels. This should do exactly what they state. Ther weird thing is that their sub-pixel seems to have the wrong number of color sub-elements.

One would expect a ratio of 2:1:1 for green:red:blue emitters. They have 4:2:1. Maybe their red emitters are much brighter than the blue, which would make sense.

They mention replacing some rows with white pixels, but their diagrams don't show anything. Maybe the media-relations people just don't know how the technology works, and are making stuff up until someone corrects them.

Tiny hints from the article...

[raygundan]

According to the article, they're generating a white signal from the RGB input and have four color elements for each pixel-- RGBW. I suspect they're arranged in a square, like:

RG
BW

or some such. This would let them apply a system like ClearType or OSX or the old Apple II subpixel rendering in two dimensions, rather than just one as with the typical horizontal RGB subpixel arrangement.

Re:Gmail!

[Anonymous Coward]

No. Hex code would look like this:

http://www.google.com/%75r%6C?%73%61=D&%71=%68%7 4%74%70%3a%2f%2f%77%77%77%2e%61%64%65%72%6b%61%63% 68%2e%6f%72%67%2f%3fu=%49%63%68

This is the hyperlink for a google redirect:
http://www.google.com/url?sa=D&q=http:/ /www.aderkach.org/?u=Ich

I hope you find this useful. The above hex is simply masking the URL in the above redirect. Unfortunately, when you use the hex to post to slashdot as the link, it converts it into text. The text "https://gmail.google.com/08udjfou38494o5rjd9357" is just text, the same way that "CLICK HERE!" would be text.

Maybe

[Andy Dodd]

They seem to be indicating that the RGBW trick is a whole different thing used to increase brightness (similar to CMYK for printers to make dark black colors).

There is a chance the subpixel rendering trick might depend on the new RGBW setup though, but it seems like they're two seperate technologies.

Re:Nothing is impossible

[stonecypher]

Because current LCD pixels require six lead lines, and we can't make lead lines small enough to shrink the pixels any further. The article phrases this badly: it's not that pixels can't be made smaller. It's that TFT LCD pixels' lead lines take all of the available current space, and there is no current technique on the horizon to solve this. Other monitor types do not have this particular problem; this is peculiar to LCD and OLED.

Good writeup on subpixel rendering

[IGnatius T Foobar]

Here's a very good writeup on how subpixel rendering works:

http://grc.com/ctwhat.htm

It goes into detail with pictures and everything, demonstrating how the technology takes advantage of the separate red, green, and blue subpixels to achieve additional smoothing.

I'm not sure how Samsung intends to implement "white subpixels" though.

Re:So does that mean...

[rpenguin]

Whoa, you're not getting it, rewt66. It sounds like you think what's going on is simply sampling of higher resolution data down to a lower resolution and claiming it's as good. (i.e. if a white pixel and a black pixel were next to each other, they would be replaced with a single 50% grey pixel.)

That's not quite the technology here. You see, a normal LCD has 'subpixels' which are really just pixels that can display one of the three additive primary colors (red, green and blue.) These pixels are necessarily not in the same exact space, and are usually arranged into rows This means that you can increase pixel resolution at the cost of color accuracy.

Today this technology is utilized by software to provide sharper text display, although if you squint you can sometimes see strange blue and red artifacts around the edge of fonts. Here's an example: close-up of black text on white background

As far as I can tell, the technology here differs in the arrangement of subpixels and the addition of a white/brightness subpixel.

Sounds bogus

[Theovon]

First, it sounds like they're simply scaling 640x480 down to 320x240 with antialiasing. Big whoop.

Second, if they only do a luma blend (ie, ignore the nonlinearity of human perception of light), then it really won't be quite the same thing. I just don't think they're doing it right, because a proper luminance blend is computationally expensive.

Technology from Clairvoyant

[happynut]

The sub-pixel technology was actually licensed from Clairvoyante, and is available to all comers. Clairvoyante calls it a PenTile Matrix.

I know they are working with other panel folks too, so you will probably see more of these type of sub-pixel displays soon.