From the time that a PenTile display first appeared in a KDDI phone using a Samsung PenTile OLED display, I began the count of products that used PenTile.  Identifying each of these products has presented some challenges, since not every product that has used a PenTile display has advertised the use of PenTile technology.  In some cases it was pointed out by customers and bloggers.  In others, I had to find the product on the shelf and examine it with my pocket microscope to be sure.  My guess is that I  may have missed some products that have used PenTile, but as of last Friday my running count came to a milestone of 100 unique products.  This included 79 smartphones, 17 digital still cameras, one mini-tablet, and 3 other miscellaneous applications.  This count includes both PenTile RGBG OLEDs as well as PenTile RGBW LCDs.  The adoption of PenTile technology has accelerated over this past year.  As the drive for ever increasing resolution outpaces the ability to achieve energy efficient high resolution solutions, PenTile technology will continue to find homes.

With the introduction of the 4.65-inch 720 HD OLED, people have now figured out that Samsung is still heavily invested in using PenTile OLED technology for high resolution applications.  The reality is that this is the only way to achieve 300 dpi OLEDs.  When people try to compare this technology to other panels it is not possible to compare a PenTile OLED at this resolution to any other high resolution RGB stripe OLED for one reason.  Such RGB stripe OLEDs do not exist .  Such technology is not possible.

When people say that this is a low cost alternative, they have it entirely wrong.  It is not less expensive to make and there is no high resolution alternative.  We only wish it were lower cost, but so far that has not proven to be the case.  Yes, a 720P OLED could be made, but only if it were one-third larger diagonal, which no doubt would most likely be more expensive.   The use of PenTile technology for OLED has been to achieve high resolution for OLED, plain and simple.

One blog http://techcrunch.com/2011/10/20/the-scourge-of-pentile-returns-with-the-galaxy-nexus/

by Kevin Coldewey of Techcrunch  says, “..For me personally, it’s a deal-breaker sight unseen…”  How can someone who claims to be an expert criticize a technology without seeing it?  PenTile has been continually improved and now is being used at a level of dot pitch where it makes more sense than ever. Still Mr. Coldewey is quick to criticize without the benefit of looking at it with his own eyes.

In this same blog, Mr. Coldewey shows our diagram that demonstrates how it can get resolution with one-third fewer subpixels, but then asks, “Does it seem logical to you that a display can increase the number of pixels created by a number of sub-elements by a third and suffer no ill effect?”  First of all I should point out that Nouvoyance never said that there were no differences between RGB stripe and PenTile displays, but that we have designed them to work well with the human vision system to take advantage of the ability to discern high resolution for luminance.  The human vision system has far less resolution for chrominance, so any relative loss of chominance resolution by PenTile is of little impact.  In short, PenTile displays are designed to look virtually the same as RGB stripe displays when applied to high resolution formats.  Through the use of subpixel rendering, along with some very effective image processing algorithms, we have achieved the ability to make displays that have superb performance at high resolution.

The analogy would be image compression.  Does it seem logical that the electronics industry can achieve image compression, allowing high quality images with so much of the raw data removed?  Perhaps to the uninitiated it seems illogical, but to the well informed it is totally logical.  The same is the case for those who are well trained in the principles of imaging science when they fully grasp the principles of PenTile image processing  technology.

Again we are seeing people going down the path of counting dots and trying to discount the resolution that is published in the spec.  This has been covered many times in the past and can be reviewed on this blog http://pentileblog.com/?p=712 and http://pentileblog.com/?p=809 where we show how this panel meets the only industry spec for display resolution from VESA http://bit.ly/qLX9Xf .  I also have published  http://pentileblog.com/?p=778, a reference to an article by the industry icon, Alva Ray Smith, written in 1995, well before PenTile.  This article makes the case very clearly that pixels are not little squares of red plus green plus blue dots.  Instead, a pixel is a simply a point plus a reconstruction filter.  It is nothing more.  PenTile uses an area resampling methodology that uses such a reconstruction filter to bring the desired luminance to each and every pixel in the display.  Color resolvability, albeit less than luminance, also can be realized at this spec.  The human vision system can resolve far less accurately the position of color than luminance so it enables PenTile to be an engineering solution that is fit for use.

Perhaps the biggest and most valid criticism of PenTile technology has be pattern visibility since the pattern is one-third larger than that of RGB stripe.  As we get to these very high resolution formats such pattern visibility disappears.  It is only easy to see the differences between RGB stripe and PenTile through the use of magnifiers.  Yes it is different than RGB stripe, but it doesn’t matter.  One has to doubt the credibility of the pundits who are so quick to criticize PenTile before they even take their first look at these panels.

My hat is off to to Daniel P at PhoneArena.com http://bit.ly/nDAdaq who provided a well-studied and balance review of PenTile OLED in this application.  As he pointed out, we have been very open about the benefits and deficits of PenTile technology and will continue to do so.  We will however continue to provide corrections when the technology is falsely implicated in artifacts that are not caused by PenTile.

One valid criticism of these new panels is that the white point is a little too blue.  This is not a PenTile issue, but rather a design choice of the panel maker since such a bias toward blue favors the lifetime of an OLED panel .  This is true for both PenTile OLED and RGB stripe OLED, so it would be good if people would stop attributing this to being a PenTile artifact.  Likewise, there has been some criticism of color shift off axis for PenTile OLED.  Again this is not a PenTile artifact, but is a result of thin film interference in the OLED layers.  This would be the case with an RGB stripe OLED just as it is for PenTile OLEDs.

Another invalid criticism is that of banding .  That was an issue last year with the original Nexus One when 5-6-5 color depth was input into the 8-8-8 PenTile engine for certain SW applications.  These new products are, to the best of my knowledge, all 8-8-8, so there is no banding to be seen.  If people claim this is still present, they need to provide some evidence rather than just conjecture.

It is our impression that consumers will be delighted with the new PenTile OLED panels in the 720P format.  The industry is now coming into the sweet spot for PenTile technology.  Do yourself a favor and go look at this with your own eyes rather than taking the word of those with a predisposed bias and an anti-PenTile agenda.

I never ceases to amaze me what people can become used to.  One example would be orthodonture.  How can a mouth full of brackets and wires be tolerated by so many teenagers?  What begins as discomfort soon become part of the background experience that is barely noticed.

Experiments with more radical perturbations have had surprising results.  People wearing lenses that invert images can adapt to this radical change in perception and see rather normally over time.  In fact, the removal of these lenses leads people to believe that they are now seeing normal images as inverted.

Adaption can also play a role in display technology.  CRTs had very evident horizontal raster lines which people stopped seeing over the years.  In the 1990s when CRTs were first being replaced with LCDs it was apparent to so many people that the LCDs were arranged with vertical color stripes which were far more distinct than the horizontal raster lines of CRTs.  Many complained that these lines were bothersome.  In time, however, the worst of critics adapted to these stripe artifacts for LCDs and no longer saw them.  What happened to the lines that were so bothersome only a short time before?

The fact is that the human vision system and the human brain is capable of developing filters for those portions of an image which are always there, and learns to look strictly at only the data that is being updated.  Such an adaption filter can be very helpful to remove these sources of annoyance.

For PenTile there is a pattern visibility that is different than the patterns seen in RGB stripe displays.  That which can initially be bothersome doesn’t change with the image data, so here again the eyes and brain are capable of developing filters that remove the pattern visibility of PenTile and allow the user to see only the image information that is changing.   I have seen such references repeatedly in recent weeks.  People comments generally sound like, the pattern in PenTile bothered me when I first got the phone, but now I don’t notice it at all unless I go out of my way to look for it in an image.   This is simply adaption.

At first you will noticed the patterns in the whites and stuff. (I actually liked it) but anyway. after a while of you using this device. the screen grows on you. I personally lost site of the patterns. so its like there not even there. And this screen is freaking bright. i have mine set on %30 and its just as bright as my sisters inspire 4g on full brightness.

but to me i love it.

I’m sure you wont be disapointed. I watch netfilx alot and it doesn’t bother me at all. its actually nice.

Vision scientists have long been aware of this phenomenon.  To understand this in more detail you can check out this link  http://bit.ly/qa7sIU   Here it says, “…If you stare at a pattern for a long period of time (usually 1 min is sufficient) the visual system becomes adapted. The processes underlying adaptation are not fully understood. Adaptation may be passive (neurones become fatigued) or active (recalibration). However, what is clear is that adaptation to a high contrast pattern has the result of making it more difficult to see a low contrast pattern…”

Not everyone adapts so readily, but most people will adapt given the time and opportunity.  Given that PenTile RGBW s is the most significant savings that can be afforded a smartphone, many have felt that it is worth the wait to allow adaption to occur.  Those who have done so have appreciated the benefits of  superior outdoor viewability and much bright displays without the penalty of short battery life.