GS3 Pentile vs GNex Pentile/Question about gaps between subpixels

**jean15paul** · 05-11-2012, 09:43 AM

Alex Dobie wrote a really good article about GS3 hype/expectations vs reality. One thing he talked about was the GS3 screen and how a lot of people are disappointed that it's pentile matrix. He went on to say that the GS3's 720p SuperAMOLED looks better than the GNex's 720p SuperAMOLED. In that paragraph he made these 2 statements:

"...Samsung came out with its 4.8-inch, 720p SuperAMOLED panel [for the GS3] (with -- gasp -- slightly lower pixel density than the Galaxy Nexus)..."

"Philip Berne reveals that the gaps between the subpixels on the S III are smaller [than on the Galaxy Nexus], making for a sharper-looking image and fewer jaggies."

I have a question about this. I understand that the GS3 has a lower pixel density than the GNex because it has the same resolution on a bigger screen. But if the GS3 has a lower pixel density then how can the gaps between subpixels be smaller? Lower pixel density seems to imply that the pixels (and subpixels I assume) are farther apart, therefore I'd expect the gaps to be bigger.

Does anyone have any insight?

(Full article here: http://www.androidcentral.com/hype-e...g-galaxy-s-iii The 11th and 12th paragraphs discuss the screen hardware.)

**MrSmith317** · 05-11-2012, 10:33 AM

The only way I can figure that the gap would be smaller is because of a bigger screen. If the screens were the same size and one had a lower pixel density then they would have to be further apart. But with a slightly bigger screen you can jam more pixels in tighter and still wind up with a lower density because of the larger screen. Basically you're skewing the dpi by not adding a full dimension more to the screen.

**jean15paul** · 05-11-2012, 10:46 AM

Originally Posted by MrSmith317

The only way I can figure that the gap would be smaller is because of a bigger screen. If the screens were the same size and one had a lower pixel density then they would have to be further apart. But with a slightly bigger screen you can jam more pixels in tighter and still wind up with a lower density because of the larger screen. Basically you're skewing the dpi by not adding a full dimension more to the screen.

But I would have thought that if you add more pixels you would increase the resolution. Is that now how it works?

Also if you're jamming more pixels in tighter, doesn't that result in a higher pixel density? Maybe I don't understand the definition of pixel density.

**MrSmith317** · 05-11-2012, 12:27 PM

Originally Posted by jean15paul

But I would have thought that if you add more pixels you would increase the resolution. Is that now how it works?

Also if you're jamming more pixels in tighter, doesn't that result in a higher pixel density? Maybe I don't understand the definition of pixel density.

You're not increasing the density enough to increase the average number of pixels per inch because you haven't added a full inch. Does that make sense? In other words the DPI is not a good indicator of picture quality.

**Kevin O'Quinn** · 05-11-2012, 12:39 PM

Something has to give. You can't have both 1) a physically larger screen and 2) subpixel that have "tighter gaps". Unless you increase the size of the subpixel, which could theoretically make the pentile layout more noticeable (but that's unlikely due to the marginal increase in screen size).

I'm hoping for some clarification because it seems like PR isn't talking to engineering before they say something. The math just doesn't work out. Also, you can't just add more subpixel to increase the density, that would throw everything all out of whack.

**jean15paul** · 05-11-2012, 01:01 PM

Originally Posted by Kevin O'Quinn

Something has to give. You can't have both 1) a physically larger screen and 2) subpixel that have "tighter gaps". Unless you increase the size of the subpixel, which could theoretically make the pentile layout more noticeable (but that's unlikely due to the marginal increase in screen size).

I'm hoping for some clarification because it seems like PR isn't talking to engineering before they say something. The math just doesn't work out. Also, you can't just add more subpixel to increase the density, that would throw everything all out of whack.

Thanks Kevin. That's pretty much what I was thinking too, but I don't have a lot of experience with phone hardware, so I thought I might be missing something. So how do we get some clarification?

**MrSmith317** · 05-11-2012, 02:12 PM

Originally Posted by Kevin O'Quinn

Something has to give. You can't have both 1) a physically larger screen and 2) subpixel that have "tighter gaps". Unless you increase the size of the subpixel, which could theoretically make the pentile layout more noticeable (but that's unlikely due to the marginal increase in screen size).

I'm hoping for some clarification because it seems like PR isn't talking to engineering before they say something. The math just doesn't work out. Also, you can't just add more subpixel to increase the density, that would throw everything all out of whack.

The math works just fine. If they added 1 actual dot per inch then they would be packed tighter but when you take total dots / screen size and DPI comes out less, it makes total sense.

**Kevin O'Quinn** · 05-11-2012, 04:23 PM

Originally Posted by MrSmith317

The math works just fine. If they added 1 actual dot per inch then they would be packed tighter but when you take total dots / screen size and DPI comes out less, it makes total sense.

Solid point. Still trying to figure out how making the gaps smaller makes the image sharper and text better. Seems like that would be an even trade to me. Make the gaps smaller, but the subpixels bigger and you basically break even. It does explain the extra brightness they are claiming, though.

Seems like the engineering time would be better spent making it RGB stripe. I mean, if they had the space to make the subpixels bigger than why not just do it right and have it be a non-pentile? Unless Samsung is skirting around the longevity issue by not going +, but that's just a guess (especially since they do have a 1280x800 SAMOLED+ panel in the Tab 7.7).

**Vladabeast** · 05-16-2012, 03:07 AM

Pentile sucks *** no matter what, but they are already coming out with SuperAMOLED HD plus so I'd hope they'd put it in the gs3 but i doubt they will. And the super lcd2 inthe one x is wayyyyyy better than the SuperAMOLED w/pentile so I'm probaably gonna pass onthe gs3

Sent from my HTC EVO 3D

**jean15paul** · 05-17-2012, 12:45 PM

I also asked this question in the comments on the blog and Alex Dobie provided a response. See below:

Alex Dobie says:
You're right, lower pixel density means the distance between pixels themselves (individual clusters of RGBG) is larger. What Phil Berne is saying is that the space between the individual red, green, blue and green *subpixels* that make up each pixel is smaller on the S III. This means the four subpixels which make up each pixel are packed more tightly together, making the PenTile matrix pattern less obvious. Hopefully that makes sense

This seems to make sense to me. If thesubpixels are closer together than you should get less jagged lines. Thoughts?

**Kevin O'Quinn** · 05-17-2012, 01:13 PM

Physically, though, things are still larger. So instead of having empty space you have color in that space. Resolution is the same, subpixels are larger. They still are "offset" in reference to each other. A pentile layout will ALWAYS have sharpness issues because of this. Perfectly straight lines just aren't possible.

Yes, this may help, or it may not. Everybody's eyes are different. Some people will notice it, some won't. Pixel density is so high that you shouldn't see it in day-to-day use.

Still technologically inferior to RGB layout, though.