Samsung Galaxy S4's is indeed a delta-shape PenTile GRGB - Galaxy S 4 Q&A, Help & Troubleshooting

I have verified that the AMOLED in Galaxy S4 is indeed a PenTile similar to S, S3, Galaxy Nexus and other brands that uses Samsung PenTile super AMOLED displays. The new S4 AMOLED have green subpixels centered in the middle of each input pixel with red and blue subpixels situated at the bottom.
Total Number of Subpixels:
G: 1920 x 1080 = 2,073,600
R=B = 1920 x 1080 / 2 = 960 x 540 = 1,036,800
Total # of RGB subpixels = 4,147,200
The Green subpixels indeed have full resolution while the Red and Blue subpixels are halved. But this does not interfere the image quality especially the PPI is 441. Since PPI is calculated based on the full pixel density along the diagonal line, it is not accurate to measure display designed for human perception with virtual resolution. Because virtual resolution utilizes less RGB subpixels to construct single pixel width or height black and white lines. It however, works exceptionally well when the lines are narrow enough to be less than our "retina resolution" which is around 0.6 arc-minutes (binary lines). Our eyes, instead, see an averaged of the black and white lines in gray at around 6 inches away from the 5" Full HD display.
The S4 AMOLED renderer intelligently shares the red and blue subpixels horizontally to achieve a correct overall color.
I have attached an example of how S4 renders the vertical lines. Horizontal lines isn't shown because S4's AMOLED is able to display black and white horizontal lines without sharing the red and blue subpixels.

Related

Gal Note True resolution good calculation

For purpose of understanding imagine two 4" screens both with 800x480 pixels resolution:
One is RGB, the other is Pentile GRGB.
So, the area of each pixel in each screen is the same, I name it 1 unit-pixel. It happens that this unit-pixel in the RGB screen has 1/3 of area in green (sub-pixel), 1/3 of area in red and 1/3 of area in blue; In Pentile this unit-pixel has 1/3 of area in green and 2/3 of area in red (double area of red); next pixel has 1/3 of area in green and 2/3 in blue (double area of blue).
Imagine now one figure with 100 pixels represented in these two screens; imagine now this figure is color green: the number of sub-pixels green is exactly the same in RGB screen as Pentile screen, this is 100 sub-pixels, and also the same in area of green.
Imagine now the figure is color red: the number of red sub-pixels in RGB is the same as it was in the green color, this is 100 sub-pixels, but in Pentile the number of red sub-pixels is half of green, this is 50 sub-pixels; however the area of red is exactly the same as it was in green.
The same happens in blue color figure.
Saying this I guess everybody understands that in a given picture, the area of green, red and blue is exactly the same in both types of screen. It doesn't matter if screen is RGB or Pentile; the area of colored sub-pixels is exactly the same in both types.
As in red color, in Pentile screen, is one unit-pixel switch on and next unit-pixel is off, and so on, (but each one with the double in area), if the resolution is a little small like 800x480 in 4" screen, indeed, we yet will be able to see black unit-pixel in the middle of each two red pixels (never forget that color area in each color, is the same as RGB).
However this effect is reduced (not completely eliminated) because in the next line the red pixel is advanced of one unit-pixel (alternated), as Pentile in sub-pixels red/blue and lines use alternate technique.
Increasing resolution to 1280x720 in 5" screen, the unit-pixels will be so small that we will not be able to see the black unit-pixels switched off in the middle of each two unit-pixels.
Furthermore, in real situation, all unit-pixels has the sub-pixels green switched on, this is exactly the same as RGB, and as already said color area is the same.
So, we get exactly the same resolution in both systems as the unit-pixels are the same in both systems and each sub-pixel red or blue have the double in area in Pentile to compensate the half number of these sub-pixels.
Calculations only with sub-pixels, not taking in account the fact that sub-pixels red and blue are double of area in Pentile, conduces to bad and misleading results.
In Galaxy S (1) red/blue sub-pixel area is double than green sub-pixel to compensatd the half number of red/blue sub-pixels.
In Note/Nexus, if the red/blue sub-pixels area is equal to green ones, then the bright of red/blue pixels must be the double of green ones (maintaining the due proportion) in order to maintain the color accuracy as the red/blue number of sub-pixels is half of green. However the resolution maintain equal as RGB because the number of unit-pixels is the same as RGB. So in this case the compensation to equal RGB screen is based in the bright of sub-pixels red/blue instead of double area.

Samsung: PenTile AMOLED displays last longer, that's why we use them

http://www.mobileburn.com/19548/new...ed-displays-last-longer-thats-why-we-use-them
Samsung announced its new Galaxy S III smartphone to great fanfare last week, though some observers weren't terribly happy with one particular feature: the 4.8-inch 720p Super AMOLED display uses a PenTile(INFO) subpixel layout instead of the generally more favorable RGB(INFO) layout. At CTIA 2012, we spoke to Samsung about its choice to use PenTile layouts in a large number of its displays, and the answer really comes down to durability and longevity.
Ever since the original Galaxy S in 2010, Samsung has used AMOLED(INFO) (usually branded as Super AMOLED or Super AMOLED Plus) displays in many of its high-end smartphones, and many consumers are big fans of them. AMOLED screens have tremendous contrast, very saturated and vibrant colors, and extremely wide viewing angles. Devices that feature AMOLED displays have a certain 'wow' factor when you first look at them, and many users appreciate that, even if the displays don't provide the most accurate color reproduction. Samsung says that it fully believes AMOLED displays are the best for its mobile devices, and that's why it uses them time and again.
However AMOLED isn't without its faults. Displays that use AMOLED technology have a tendency to deteriorate over time. One doesn't have to look back that far to remember the problems Google had with the original Nexus One smartphone, which featured an AMOLED screen. There were numerous reports of screen deterioration after only a few months of use, and in some cases the display was rendered unusable (HTC, the maker of the Nexus One, eventually switched to using Super LCD displays in later versions of the phone, though it cited supply constraints as the reason for the switch).
Samsung's Philip Berne explained to me that the blue subpixels on AMOLED displays actually degrade the fastest - quicker than the red or green subpixels. With a PenTile layout, the subpixels are arranged RGBG (red, green, blue, green), so they feature more green subpixels and fewer red or blue subpixels than an RGB stripe layout with the same resolution. Because of this, AMOLED displays that have the PenTile layout tend to have a longer lifespan than those with RGB layouts. Since Samsung is selling its phones to users that usually keep them for 18 months or longer, it has to be sure that the display will still offer peak performance at that time. According to the company, PenTile AMOLED displays have proven to be more reliable than those with RGB layouts.
Those that have issues with the PenTile arrangement usually complain that the screen does not look as crisp as an RGB display or that there is odd color fringing along the edges of images, such as app icons. While Berne did agree that the PenTile arrangement's faults are pronounced at lower resolutions, such as qHD or WVGA, high-resolution displays hide the problems due to the sheer density of pixels. The Galaxy S III and the Galaxy Note, for example, both feature high-resolution Super AMOLED displays with PenTile subpixel arrangements (the Galaxy S III has a 1280 x 720 pixel screen, while the Note has a 1280 x 800 pixel display). Under a microscope, one can see the pixel layout on these displays, but in real-world use, it is not visible to the vast majority of users. To that point, the Galaxy S II, which had a lower-resolution WVGA (800 x 480 pixel) display, featured an RGB layout for its subpixels.
Today's choice to use PenTile in its high-end Super AMOLED displays doesn't mean that Samsung isn't working on or won't develop future AMOLED displays that use the RGB pixel layout, provided it can maintain reliability across the board. In fact, the Samsung Galaxy Tab 7.7 tablet features a 7.7-inch Super AMOLED Plus display with 1280 x 800 pixels and an RGB pixel layout, though that screen is obviously larger than what we see on smartphones, thereby making any PenTile-related issues more noticeable.
Is the PenTile subpixel layout something that should be a concern for prospective buyers of the new Galaxy S III? We really don't think so, and in our hands-on time with the device, we really could not see any issues with the screen. Trust me, I tried. Berne did point out that the 4.8-inch display on the Galaxy S III is improved over the 4.65-inch 720p Super AMOLED screen used on the Google Galaxy Nexus, as it features smaller gaps in its subpixel matrix, further minimizing the fringing effects of the PenTile layout.
Some reviewers and users may disagree, and contend that "once you see the PenTile, you can't unsee it," but we really think that the average smartphone buyer (the people that Samsung is actually selling the phone to) will never be the wiser. Additionally, as smartphones get higher and higher density displays, the argument over PenTile and RGB subpixel layouts will become less and less relevant. Are we going to be discussing this matter when smartphones with 1080p displays, perhaps some with PenTile subpixel layouts, come out in the next year or so? We really doubt it.
i wont believe that unless it comes straight from a Samsung press release article
I would say this is a make over from samsung, simply the technology is not ready for mass production hence the pentile.

[Q] How to calculate the Red & Blue subpixel has 312ppi on S4?

According to http://www.displaymate.com/Galaxy_S4_ShootOut_1.htm
"The pixels on most current OLED displays have only 2 sub-pixels in each pixel instead of the standard 3 Red, Green, and Blue sub-pixels found in most other displays and display technologies. Half of the PenTile pixels have Green and Red sub-pixels and the other half have Green and Blue sub-pixels, so Red and Blue are always shared by two adjacent pixels....
here are 312 Red and Blue Sub-Pixels Per Inch"
We know that Green subpixels has full resolution 1920 x 1080 at 5 inches with 441 SPPI. If the number of subpixels of Red/Blue is half that of the green subpixels, why is it 312 SPPI and not 220 SPPI?
G = sqrt(1920^2 + 1080^2)/5 = 441 SPPI
R = B = sqrt((1920/2)^2 + (1080/2)^2)/5 inches = 220 SPPI

Note 12.2 screen has 4 Million less subpixels...

The Note 12.2 uses a pentile [RB][GW] subpixel layout vs the TabPro 8.4 which has full [RGB].
Pentile screens use just 2/3 of the subpixels compared to full RGB.
Accordingly subPixel counts:
Note 12.2 ... 2560x1600x2 gives about 8 million sub pixels
tabPro 8.4 ... 2560x1600x3 gives about 12 million
Disappointing for a device priced so high with a 'Pro' tag?
SonicTab said:
The Note 12.2 uses a pentile [RB][GW] subpixel layout vs the TabPro 8.4 which has full [RGB].
Pentile screens use just 2/3 of the subpixels compared to full RGB.
Accordingly subPixel counts:
Note 12.2 ... 2560x1600x2 gives about 8 million sub pixels
tabPro 8.4 ... 2560x1600x3 gives about 12 million
Disappointing for a device priced so high with a 'Pro' tag?
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i believe that the actual experience of using the tablet and getting the best out of it matters more than the on paper calculations
I have a Nexus 10 and a Note Pro 12.2 and can't tell any difference in pixel density so quit complaining about paper specs. It's a great tabet!
rkirmeier said:
I have a Nexus 10 and a Note Pro 12.2 and can't tell any difference in pixel density so quit complaining about paper specs. It's a great tabet!
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Turn that in to PPI and it doesn't look so bad. The gross PPI for the N12.2 is 247. The addition of the white sub-pixel (25% of the total count) reduces the RGB pixels by 8% each leaving them at 227 PPI each. The iPad Air is at 264 PPI and the net RGB for the N10.1-14 is 274 (gross is 299) resulting in the N12.2 having 14% fewer RGB pixels per inch than the iPad and 17% less than the N10.1-14. It's 24% less than the N10 which uses a RGB stripe display. Whether those PPI reductions are comparatively noticeable depends more on individual visual acuity and the distance the device is viewed from than anything else. Some reviewers commented on the display being less sharp when compared to the Tab|Pro 8.4/10.1 and N10.1-14.
Same here. No perceived difference in sharpness/quality with my Nexus 10.
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BarryH_GEG said:
Turn that in to PPI and it doesn't look so bad. The gross PPI for the N12.2 is 247. The addition of the white sub-pixel (25% of the total count) reduces the RGB pixels by 8% each leaving them at 227 PPI each. The iPad Air is at 264 PPI and the net RGB for the N10.1-14 is 274 (gross is 299) resulting in the N12.2 having 14% fewer RGB pixels per inch than the iPad and 17% less than the N10.1-14. It's 24% less than the N10 which uses a RGB stripe display. Whether those PPI reductions are comparatively noticeable depends more on individual visual acuity and the distance the device is viewed from than anything else. Some reviewers commented on the display being less sharp when compared to the Tab|Pro 8.4/10.1 and N10.1-14.
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All these calculations are a waste of time and effort. I can't tell the difference side by side so no one is going to be able to honestly perceive that one is better then another... These kind of arguments and numbers are only for haters or people who can't afford a device but want to convince themselves they really don't want it because of some technical specs that can't be perceived in real world usage/conditions.
Look it is what it is.
Samsung used a pentile screen in the 12.2 . Pentile screens have 2/3 of the sub pixels of a normal RGB display.
The display quality of the TabPro 8.4 is incredible, 1078 sub pixels per inch,
whereas the 12.2 pentile display clocks in at 494 sub pixels per inch.
As others have noted, the 12.2 Note screen is more than usable, but it's inferior to a full RGB display.
SonicTab said:
Look it is what it is.
Samsung used a pentile screen in the 12.2 . Pentile screens have 2/3 of the sub pixels of a normal RGB display.
The display quality of the TabPro 8.4 is incredible, 1078 sub pixels per inch,
whereas the 12.2 pentile display clocks in at 494 sub pixels per inch.
As others have noted, the 12.2 Note screen is more than usable, but it's inferior to a full RGB display.
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So you are not getting one ?!
As I said actual experience matter than paper specs and calculations etc. I have seen no one disappointed about the screen not on here or in a YouTube video but you . everyone is charmed by the beauty of the screen and happy with it . those calculations are not a deal breaker for anyone around here and if you are not happy with what you would get with the note pro you could simply get the 8.4 tap pro its a personal reference .
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SonicTab said:
Look it is what it is.
Samsung used a pentile screen in the 12.2 . Pentile screens have 2/3 of the sub pixels of a normal RGB display.
The display quality of the TabPro 8.4 is incredible, 1078 sub pixels per inch,
whereas the 12.2 pentile display clocks in at 494 sub pixels per inch.
As others have noted, the 12.2 Note screen is more than usable, but it's inferior to a full RGB display.
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Sorry but you are being stupid. Stop analyzing the specs and actually try out the devices. No way you can perceive any difference under normal operating conditions. I truly feel sorry for you...
It's an lower quality display. The difference can be seen, and stated and is unexpected in a premium product.
If your charmed by the product or unable to see the difference, all the better.
Maybe Samsung has judged its target audience correctly.
SonicTab said:
Look it is what it is.
Samsung used a pentile screen in the 12.2 . Pentile screens have 2/3 of the sub pixels of a normal RGB display.
The display quality of the TabPro 8.4 is incredible, 1078 sub pixels per inch,
whereas the 12.2 pentile display clocks in at 494 sub pixels per inch.
As others have noted, the 12.2 Note screen is more than usable, but it's inferior to a full RGB display.
Click to expand...
Click to collapse
SonicTab said:
The Note 12.2 uses a pentile [RB][GW] subpixel layout vs the TabPro 8.4 which has full [RGB].
Pentile screens use just 2/3 of the subpixels compared to full RGB.
Accordingly subPixel counts:
Note 12.2 ... 2560x1600x2 gives about 8 million sub pixels
tabPro 8.4 ... 2560x1600x3 gives about 12 million
Disappointing for a device priced so high with a 'Pro' tag?
Click to expand...
Click to collapse
Actually the way pentile and rgb stripe displays render information is totally different. Rgb use an entire pixel (rgb) to create an image. Rgbw displays render on the subpixel level. The pixels actually have no locked in grid they must conform to but rather work with all those around them to render the same resolution image as rgb with 2/3 of the subpixels. There is no discernable difference except that rgbw actually conforms to the process of the human eye better and thus can achieve better color parity with real life.
PenTile® technology is biomimetic, meaning it is designed to compliment the complex mechanics of the eye-brain system. As a simple example of eye mechanics consider how the eye utilizes the color blue. The eye has cone receptors that sense color and brightness, and discern patterns. These cones are sensitive to different wavelengths of color—primarily red, green, and blue. The blue cones detect mostly color (chroma) information, while the red and green cones do most of the work resolving images by discerning luminance, edges, and structural details of images, as well as contributing to color vision. The red and green cones are used independently, each cone seeing a "dot" of black and white—ignoring its color to produce high resolution luminance perception—and are used in opposition, comparing the amount of red versus green, to produce low resolution color perception.
If there was an obvious disadvantage I doubt one of the largest and most successful electronics companies to ever exist would not use pentile. Or have you all forgotten that the NOTE 3 pentile is hailed as the best screen on a phone period (with regards to new 2k screens coming this year) even beating out all lcd rgb competition?
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SonicTab said:
Maybe Samsung has judged its target audience correctly.
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^This.
Measurement is objective, but enjoyment is subjective.
Duly.noted said:
Actually the way pentile and rgb stripe displays render information is totally different. Rgb use an entire pixel (rgb) to create an image. Rgbw displays render on the subpixel level. The pixels actually have no locked in grid they must conform to but rather work with all those around them to render the same resolution image as rgb with 2/3 of the subpixels. There is no discernable difference except that rgbw actually conforms to the process of the human eye better and thus can achieve better color parity with real life.
PenTile® technology is biomimetic, meaning it is designed to compliment the complex mechanics of the eye-brain system. As a simple example of eye mechanics consider how the eye utilizes the color blue. The eye has cone receptors that sense color and brightness, and discern patterns. These cones are sensitive to different wavelengths of color—primarily red, green, and blue. The blue cones detect mostly color (chroma) information, while the red and green cones do most of the work resolving images by discerning luminance, edges, and structural details of images, as well as contributing to color vision. The red and green cones are used independently, each cone seeing a "dot" of black and white—ignoring its color to produce high resolution luminance perception—and are used in opposition, comparing the amount of red versus green, to produce low resolution color perception.
If there was an obvious disadvantage I doubt one of the largest and most successful electronics companies to ever exist would not use pentile. Or have you all forgotten that the NOTE 3 pentile is hailed as the best screen on a phone period (with regards to new 2k screens coming this year) even beating out all lcd rgb competition?
Sent from my SCH-I605 using XDA Premium 4 mobile app
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PREACH.
The only other image related difference, I believe, is that the tab can record HD video at a higher fps. The camera only weighs in at a craptastic 8 MP, and I don't use my tablet, of all things, to film video. The s-pen, on the other hand, is fantastic for graphic work.
rkirmeier said:
Sorry but you are being stupid. Stop analyzing the specs and actually try out the devices. No way you can perceive any difference under normal operating conditions. I truly feel sorry for you...
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Click to collapse
How is this stupid? We are not talking about a $100 or a $200 device; this is the most expensive Android tablet where EVERYTHING should be premium. When the build quality is already meh, not having 2560x1600 at standard RGB stripe for a LCD is a kick to the teeth.
The comparison with the Note 3 is asinine, because this is not 1080p AMOLED on a 5.7" screen where the tradeoffs with Pentile are more than worth it. 2560x1600 RGB is only 227 ppi, Pentile reduces it to 2/3 to 150 ppi. The claim you make that people can't see the difference like Retina iPad is ridiculous.
My brother has the 12.2 which I have actually used it so don't use the "you didn't tried it out hurr hurr" excuse to shut people up. Straight edges are clearly blurrier than my iPad Air. But hey if you like Samsung to continue selling you inferior specs at high prices be their guest.
But at the end it's not the pixel density. If you get the same effect with new technique, you don't need so high density. But as you said you see the difference in straight edges so probably buyers should then first check the screen do they see the same or not.
Sent from my N8000.
I have the note 3, note 10.1 2012 and the note pro 12.2, the note pro is much better than my note 3 and my note 10.1 2012 combined. If you want to complain about ppi, then you should complain about the first note 10.1. 1280 x 800 on a 10.1 inch screen vs 2560 x 1600 on a 12 inch screen. Considering the first note 10.1, that is a screen upgrade to me.
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Metallic Palladium said:
How is this stupid? We are not talking about a $100 or a $200 device; this is the most expensive Android tablet where EVERYTHING should be premium. When the build quality is already meh, not having 2560x1600 at standard RGB stripe for a LCD is a kick to the teeth.
The comparison with the Note 3 is asinine, because this is not 1080p AMOLED on a 5.7" screen where the tradeoffs with Pentile are more than worth it. 2560x1600 RGB is only 227 ppi, Pentile reduces it to 2/3 to 150 ppi. The claim you make that people can't see the difference like Retina iPad is ridiculous.
My brother has the 12.2 which I have actually used it so don't use the "you didn't tried it out hurr hurr" excuse to shut people up. Straight edges are clearly blurrier than my iPad Air. But hey if you like Samsung to continue selling you inferior specs at high prices be their guest.
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Good, I hope you don't buy a 12.2 for this reason. No one really cares and it's your loss... I firmly stick by my claims, I have better then 20/20 vision and at normal viewing distance (i.e. 18inches or so) it's impossible to tell the difference. You go ahead and stick face right up to the tablet screens and compare them side by side finding that under non normal usage it's technically possible to see a slight difference if that is what you need to do. 99.9% of people who want this tablet have no issue with the screen cause if you take away the specs and evaluate the screen under normal usage conditions it's as good as anything on the market. If you think your little online rant about the resolution is going to force Samsung to make a screen that meets your specs you need a reality check. I'm going to enjoy my Note 12.2 and in a year from now Samsung will likely release a newer upgrade model with a "better" screen (as that is what happens every year) that may meet your technical requirements. Until then you enjoy your little iPad Air and I'll me enjoying my Note 12.2!
How is this thread still going? Either you buy one, or you don't. I bought it, and I'm never looking back. It has all the functionality I need, plus things I've not yet gotten around to messing with. It's an awesome tablet. If subpixels are what you're in the market for, then you have done your homework and know this isn't what you need.
This is what I need. Very pleased.
Thank you, and goodnight.
Metallic Palladium said:
How is this stupid? We are not talking about a $100 or a $200 device; this is the most expensive Android tablet where EVERYTHING should be premium. When the build quality is already meh, not having 2560x1600 at standard RGB stripe for a LCD is a kick to the teeth.
The comparison with the Note 3 is asinine, because this is not 1080p AMOLED on a 5.7" screen where the tradeoffs with Pentile are more than worth it. 2560x1600 RGB is only 227 ppi, Pentile reduces it to 2/3 to 150 ppi. The claim you make that people can't see the difference like Retina iPad is ridiculous.
My brother has the 12.2 which I have actually used it so don't use the "you didn't tried it out hurr hurr" excuse to shut people up. Straight edges are clearly blurrier than my iPad Air. But hey if you like Samsung to continue selling you inferior specs at high prices be their guest.
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Samsung FIRMLY believes that pentile is a better screen technology than lcd they are the ones driving it's development. It is more akin to how the human eye actually works and it is easier on the eyes. The number of sub pixels is the same just one per every four is white, It is 30% more energy efficient and it requires fewer sub pixels to display at the same resolution, the human eye will see it the same as a higher resolution. To be technical though gentile displays have ZERO sub pixels. Each individual subpixel is rendered separately. They are not in pre defined groups and can be combined into any number of logical pixels. So technically the screen is using 12,288,000 individual pixels.*
conventional RGB stripe displays render (draw) images by assigning a color and luminance (brightness) to an entire RGB-triplet as a whole pixel, adjusting its three RGB subpixels to set a single addressable point. Images on a PenTile RGBW™ panel are subpixel rendered, meaning they are drawn at the subpixel level (the individual points of light), rather than to the whole pixels of an RGB stripe display. In fact "pixels" in the traditional sense have been eliminated in PenTile RGBW™ displays; individual subpixels are not restricted to use in one pixel group, but instead participate in multiple "logical" pixels in their surrounding vicinity.
Subpixel rendering dramatically increases addressability and enables the sophisticated image processing used in PenTile RGBW™ displays.
That is from nouyance the company that invented pentile and rgbw They also say
PenTile® technology is biomimetic, meaning it is designed to compliment the complex mechanics of the eye-brain system. As a simple example of eye mechanics consider how the eye utilizes the color blue. The eye has cone receptors that sense color and brightness, and discern patterns. These cones are sensitive to different wavelengths of color—primarily red, green, and blue. The blue cones detect mostly color (chroma) information, while the red and green cones do most of the work resolving images by discerning luminance, edges, and structural details of images, as well as contributing to color vision. The red and green cones are used independently, each cone seeing a "dot" of black and white—ignoring its color to produce high resolution luminance perception—and are used in opposition, comparing the amount of red versus green, to produce low resolution color perception.
The PenTile RGBW™ layout uses each red, green, blue and white subpixel to present high-resolution luminance information to the red and green cones, while using the combined effect of all the color subpixels to present lower-resolution chroma (color) information to all three cone types. Combined, this optimizes the match of display technology to the biological mechanisms of human vision.
Other human-vision factors such as the logarithmic representation of luminance values, variable resolution between the center and edge of vision, and the separation and compression of brightness and color differences are also exploited in the design of PenTile RGBW™ displays.
The human eye perceives the resolution of the PenTile RGBW™ panel as the same as an equivalent RGB stripe panel, yet the PenTile®*panel uses one-third fewer subpixels. Consider the figure below to understand how this is accomplished.
At the top is the PenTile RGBW™ layout; at the bottom RGB stripe. The circle at the bottom center demonstrates the finest pattern of vertical black and white lines an RGB stripe display is capable of rendering. This requires three columns (R + G + B) be turned "on" and an equivalent width of three columns be turned "off" to write one cycle of a black and white line. From a suitable distance this collection of color subpixels appears to the eye as a white line.
The top center circle shows the equivalent pattern of vertical black and white lines written to the PenTile RGBW™ layout. From a distance the array of color subpixels in two columns will appear to the eye as a white line, identical to that generated by the RGB stripe layout, and the following two columns will write the corresponding black line. With only four columns being used to accomplish the same linear cycle that required six columns for legacy RGB stripe, two columns are saved. Hence, PenTile RGBW™ technology maintains the same resolution with one-third fewer columns, one-third fewer subpixels and one-third fewer transistors in the array. This results in wider columns and improved aperture ratio (ratio of transmissive area of a subpixel to the total area of that subpixel).
The circles on the right of the figure demonstrate the finest pattern of black and white lines which may be written horizontally to RGB stripe (bottom) and PenTile RGBW™ (top). Note that both layouts require the same number of rows for horizontal lines.
from this information we can see that a rgb display and a rgbw pentile are equal in displayed resolution and the pentile is more efficient. In black and white images and full color media Petite and rgb are 100% indistinguishable and only when displaying text against a fully saturated background (color text against a solid Colored background) or a sudden transition between two colors can a difference be seen and these are almost unnoticeable on high density displays like the Note 2014 or Note 12.2 pro. What you call drawbacks to pentile I call progress and efficiency. If I can't see a difference there isn't one. Only mine is bigger and more useful with better battery life. I owned the 2014 and work around and begrudgingly sell ipad airs on regular basis. I also have perfect vision in one eye and nobody I have EVER had come into my store has seen the 12.2's Screen as anything short of magnificent. Yes I suppose if you get close enough to your screen that you can barely focus on it that You could see a difference but ya Know I have a life and at normal viewing distances it is flawless. I mean I guess I better not buy a laptop anytime Soon since their dpi's are lower than an ipads right? Or if I want something really worth owning I need that 20" 4K tablet. And my TV is only 1080p? Its 50" THAT'S ONLY 44 DPI OMG I BETTER TRASH IT!!! Forget viewing distances I can't believe I enjoy this crap. I need at least an 8K tv to get a good dpi now I just need to wait about 6 years before I can own a tv again. And a 100" tv? Give me 16k and we can talk.
ExtremeRyno said:
How is this thread still going? Either you buy one, or you don't. I bought it, and I'm never looking back. It has all the functionality I need, plus things I've not yet gotten around to messing with. It's an awesome tablet. If subpixels are what you're in the market for, then you have done your homework and know this isn't what you need.
This is what I need. Very pleased.
Thank you, and goodnight.
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you said what i wanted to say exactly last night but i decided not too since things are getting awkward and pointless since he clearly is decided not to buy it but also the thread seems to be to make people stop buying the device based on some quality calculations

About DPI confusion

Hello ,
I read on gsmarena that grand i9082 has 187ppi screen..with some resolution..now I am actually confused as gsmarena mentioned the resolution and we can change the PPI using some procedure...so after that we can arrange more items on our screen ..meaning we are actually changing the resolution..am I right?....so a phone with 440 PPI is same as modified ppi grand..??
DPI and PPI are different terms changing DPI is possible to certain limits but ppi cannot be changes to give a idea let me explain .
A pixel is the smallest indivisible unit of information in a digital image. Pixels may be displayed, or they may be printed, but you can't divide pixels into smaller pieces to get more information. How many channels and bits per channel make up one pixel is the measure of how subtle the information in a pixel may be, but the basic fact is that 1 pixel the smallest increment of information in an image. If you do video, you know that pixels don't have to be square -- they are non-square in all older video formats. Square or not, a pixel is still the smallest unit of a picture.
An inch is a unit of linear measurement on a surface, which could be a screen or a piece of paper.
A dot is, well, a dot. It can be a dot on a screen, or it can be a dot produced by a printhead. Like pixels, dots are atomic. They're either there, or they're not. How much fine detail a screen can display depends on how close the dots are (what they used to call "dot pitch" in the old CRT days). How small the dots are from an inkjet, a laser printer or an imagesetter determines how much fine detail it can reproduce.
Dots per inch is fairly easy. A screen has so many dots (each comprising R, G and B elements) per inch of screen. It's the same on paper. A 1200 dpi printer can lay down 1200 dots in one linear inch. In describing screen detail or printer output, dots per inch is the correct term.
PPI is where the confusion comes in. An image has so many pixels. Its metadata contains an output size in inches, cm, mm, M&Ms, whatever. It's the width in pixels divided by the output width in the metadata that "per inch" comes from. So the same image with different metadata may be 72 ppi, 150 ppi or 8000 ppi. The image information is the same; all that's changed is the metadata.
A quick and easy demo that somewhat illustrates the point is to make some marks on a piece of elastic, say five to an inch. Stretch the elastic to twice its length. The number of marks hasn't changed, even though the "marks per inch" is now 2.5.
You can see this in Photoshop if you turn off Resample Image and change the size. The ppi value changes to reflect how small the pixels must be reproduced in order to hit the measurement value in inches/cm/mm etc. Note that in this case the Pixels fields are disabled. You can't change those values unless you resample.
Mass confusion entered in when image pixels were mapped to screen dots in web browsers. A 200 pixel image shows up as 200 pixels in a browser. How large it is, measured with a ruler, depends on the dots per inch of the screen. The image metadata might say it's 200 ppi or 72 ppi or 1 ppi, it will still occupy exactly 200 screen dots. The world remains fixated on "72 ppi for the web," so the question of "what's the right resolution for web images" keeps coming up, and the correct answer, "it doesn't matter," keeps being supplied ad nauseam.
If you're still with me, there's one last step that brings the two together.
A 720-pixels-wide image at 10 physical inches wide has a resolution of 72 pixels per inch. If you print it on a 1200 dpi printer, there will be 1200 dots per inch on the paper, but the image is still 72 pixels per inch. That's why it looks like crap. On the other hand, a 7200 pixels wide image printed at 1 inch wide will exceed the resolution of our 1200 dpi printer. Photoshop (let's say) and the printer driver decide which pixels to throw away and which to actually print. Some of the printed dots will be averaged among adjacent image pixels, but, regardless, some of the image information has to be thrown away. The output will be 1200 dpi, but the resolution of the printed image will have been reduced to at most 1200 dpi by the software.
So changing DPI is just like changing resolution on PC..but the phone PPI will be same as it is in the hardware..?? Can we feel phone with 180ppi and 440 PPI as different from each other while using?

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