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

Samsung uses PenTile technology in virtually all of their Super AMOLED displays, which are used in most of the company's smartphones - including the Galaxy S7 and S7 edge.

Samsung GS6 and GS6 Edge photo

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.

Further reading