PenTile RGBG matrix technology explained
Samsung's Pentile matrix technology is a sub-pixel design architecture family. The basic PenTile structure is the RGBG matrix. In RGBG PenTile displays there are only two subpixels per pixel, with twice as many green pixels than red and blue ones. You can see a PenTile matrix vs a Real-Stripe one on the images below (the PenTile is on the right):
The Pentile technology was commercialized by Clairvoyante. In March 2008, Samsung bought the company's PenTile related IP and technology, and formed a new company called Nuovoyance to continue development of this display technology. Here's an image from Nuovoyance showing Pentile vs RGB matrix (which they call a 'legacy' matrix):
PenTile relies on the human eye design - if you reduce the number of blue subpixels, you barely reduce the image quality. There are other advantages to PenTile displays (for example longer liftime, which will be explained below). But even Samsung admits that a real-stripe RGB matrix is better than Pentile, for example here's some marketing image from Samsung showing how a non-Pentile display (the Super AMOLED Plus) is better than the pentile Super AMOLED:
Some people indeed do not like PenTile displays. Mostly it seems because there is a visible pattern when you look at the display up close. Your eyes get used to this pattern quickly though, and the higher resolution the display is, the less visible the pattern is. Modern PenTile OLED displays reach very high pixel densities that make it virtually impossible to notice the patern.
Samsung's AMOLED and Super AMOLED displays
Diamond Pixel Pentile
Samsung's latest Super AMOLED displays adopt a new subpixel arrangement called Diamond Pixel. The first phone to use this pentile type was the Galaxy S4 (later phones adopted a slightly different Diamond pattern). In a Diamond Pixel display, there are twice as many green subpixels as there are blue and red ones, and the green subpixels are oval and small while the red and blue ones are diamond-shaped and larger (the blue subpixel is slightly larger than the red one). The diamond shapes were chosen to maximize the sub-pixel packing and achieve the highest possible PPI. The greens are oval because they are squeezed between the larger red and blue ones.
Pentile displays last longer
One of the advantages of PenTile displays is that they last longer. In fact today this is one of the major reasons Samsung are using PenTile for high-resolution (over 230 ppi) OLEDs. Read here for Nuovoyance (Samsung's company in charge of PenTile) explanation.
The latest Pentile news:
DisplayMate: the Galaxy Note 3 has the best performing OLED display ever, beats LCDs across the board
DisplayMate, the display testing, measurement and calibration experts just got their hands on a pre-release Galaxy Note 3 production unit, with its 5.7" Full-HD Super AMOLED display (386 PPI, PenTile). They put the unit to extensive testing (and also compared it to the Note 2). The conclusion? This is the best performing OLED display ever and it beats LCDs across the board!
The most notable advancement in this new panel is the high brightness. It can achieve 660 cd/m2 in high ambient light. It's not just 55% brighter than the Note 2, it's actually the brightest display ever tested at DisplayMate. A very notable achievement for Samsung's OLEDs, which were lagging behind LCDs in brightness.
When Samsung unveiled the Galaxy Note 3 they said it's got a 5.7" Full-HD Super AMOLED display (386 PPI) - but they didn't reveal what is the sub-pixel arrangement. Some sites say it is a Pentile display while other say it not.
According to Chinese site RBMen, the Note 3 uses a Diamond Pixel architecture - similarly to the Galaxy S4. Diamond Pixel is indeed a PenTile subpixel scheme, and there are twice as many green subpixels as there are blue and red ones. The green subpixels are oval and small while the red and blue ones are diamond-shaped and larger. So perhaps both reports are right: it is indeed a PenTile display, but not a regular one...
French site Lesnumeriques posted an article on Samsung's KN55S9C curved OLED TV, in which they include a macro-photo showing the TV's sub pixels up close:
As you can see, the blue subpixels are bigger than the red and green ones (about twice as large). This was designed this way because the blue OLED has the lowest lifetime - if it is bigger then you can lower the brightness and so conserve lifetime. We've seen many OLED displays with differently-sized subpixels - including PenTile ones and the rather unique display used in the Note 2.
When Samsung launched the GS4, they said the Super AMOLED display uses PenTile. Back in January, it was reported that Samsung will adopt a new subpixel scheme that uses diamond sub-pixels, but up until now we didn't hear anything official from Samsung. Today the company finally did acknowledge the new design, and published two closeup photos of the GS4 display.
Diamond Pixel, as Samsung's calls their new design, is a PenTile subpixel scheme, in which there are twice as many green subpixels as there are blue and red ones. The green subpixels are oval and small while the red and blue ones are diamond-shaped and larger (the blue subpixel is slightly larger than the red one). DisplayMate says that this is because green is the most efficient (and long lasting) OLED emitter while the blue has the shortest lifetime.
Samsung unveiled their new flagship smartphone, the Galaxy S4. As expected, it sports a 4.99" Full-HD (1920x1080, 441 PPI) Super AMOLED display behind a Corning Gorilla Glass 3. This phone will launch towards the end of April worldwide (on 327 carriers in 155 countries). The S4 seems to be more of an upgrade to the S3 than a revolutionary new handset.
According to previous reports, Samsung Display started producing these 5" Full-HD AMOLED panels in February at a rate of 3 million units per moth (this will grow to almost 10 million monthly units in coming months). The S3 is Samsung's best selling and fastest selling smartphone, and obviously the company hopes that the S4 will sell even better.
According to Digitimes, Samsung's upcoming "next-gen" AMOLED panels will use a new pixel layout. Reportedly, Samsung are developing hexagon and diamond shaped pixels. This means that Samsung will increase the resolution but the picture will suffer due to jagged pixel artifacts and blurring. It's probably that at such high pixel density this won't actually be noticed, but still.
In the Galaxy Note II Samsung introduced a new sub-pixel scheme, an RGB matrix in which the blue subpixel is twice as large as the red and green ones - which achieved 267 PPI. Obviously the new 4.99" Full-HD displays have a much higher PPI (440). I assumed Samsung will use the same PenTile arrangement used in most of their AMOLED displays.
Samsung announced today that the Galaxy Note 2 has launched in South Korea. It will soon launch worldwide in 128 countries via 260 mobile carriers. The Note II is the successor to the popular "Phablet" Galaxy Note. This large phone/tablet has a 5.5" HD Super AMOLED display (1280x720, non-Pentile), a quad-core 1.6Ghz processor and a large 3,100mAh battery. The Note II is only 9.4mm thick.
Update: I just talked to DisplayMate's Raymond Soneira, and he says that the power-consumption test was done on an all-white screen. This is the worst-case scenario for an OLED, and so real-world results will be better (depending on your typical phone usage of course).
DisplayMate posted an interesting and comprehensive comparison between the iphone 5 IPS-LCD and the Super AMOLED HD display used in the Galaxy S3. They say that the iPhone's display is superior - its a very accurate display, and it's the best Smartphone display they have ever seen. It's actually quite an improvement over the display used in the iPhone 4S.
DisplayMate says that the OLED display on the S3 is not as bright as the LCD, it is less readable in high ambient lighting, it has saturated green and distorted and exaggerated colors. They still complain about Samsung not calibrating the color gamut. On the other hand, they say that OLED is a new technology and hasn't been refined to the same degree as LCDs yet. They still say OLEDs have a very promising future.
Yesterday I posted about the Galaxy Note 2 subpixl scheme, with the 5.5" 1280x720 HD Super AMOLED display featuring 267 ppi (with three subpixels per pixel). Our readers pointed out that the new scheme used in the Note 2 looks very much like Ingis Innovations' patented HR pixel structure (as part of their AdMo-p technology). This may explain how Samsung managed to get good enough lifetime at such a high PPI without PenTile.
Just as a reminder, here's how the Note 2 pixels are arranged. It's not exaclty the same as in the HR structure as the red and green sub-pixels have the same size. In any case:
When Samsung announced the Galaxy Note 2, with its 5.5" 1280x720 HD Super AMOLED display, I assumed it was a Pentile display. But it seems that the Note 2 actually uses an RGB matrix in a unique arrangement (see the photo below). Samsung calls this new matrix S-Stripe. This is rather confusing on several accounts - mostly because up till now Samsung used the brand Super AMOLED Plus for non-pentile OLEDs.
Just a few weeks ago we explained that Pentile OLED displays enable higher lifetime, and we were told that for an RGB OLED with over 230 PPI, lifetime becomes too low for Samsung and they choose Pentile in those displays. But the Note II has a PPI of 267 - the highest PPI non-Pentile OLED. This means it has a lower lifetime compared to a Pentile display (but the advantage is that there's no visible Pentile pattern of course).