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With the introduction of the Galaxy S4 and its 440 PPI PenTile OLED display, a new bar has been set for high resolution OLED displays and for high performance smartphones.

Friends and colleagues have heard me repeat an old expression, “ There is no such thing as being too thin or too rich.”  When it comes to displays it seems that there is a similar thing that can be said that a display cannot be too thin or too high in resolution.  In point of fact there are people who are too thin and there are limits to how much resolution can be seen.  But, we are not at that top end resolution yet.  My prediction is that the march toward increasingly higher resolution will end only when we get to 600 PPI.  The reason for this is that there are people who can focus (accommodate) a display at very close distances and can also resolve 50 cycles/degree.  Consequently, there will be some people who can still perceive pattern visibility.  At 440 PPI the PenTile OLED in the Galaxy S4 has exceeded the ability to see pattern visibility for all but those very few people with better than average accommodation and visual acuity.

At 440PPI the only way to retain the brightness and lifetime of an OLED display is with PenTile technology.  Don’t get me wrong, Samsung has made great strides in pushing their resolution capability to higher levels for both RGB stripe OLED as well as for PenTile OLED.  There have been reports that this is a result of combining PHOLED for improved red and green efficiency and OLED technology for blue (bit.ly/X51DsE).  Such a technique would allow for red and green subpixels to occupy still smaller percentages of the display real estate.  If a 440 PPI PenTile OLED is possible, then, by definition, an RGB stripe at 293 PPI is also possible.  That said, even for a 293 PPI display if one uses PenTile technology one can push up the brightness to improve outdoor viewability—a better choice for most users.

One blog today (http://bit.ly/15cQhWP  ) quoted me as saying that there is no technical solution for replacing PenTile in OLED smartphone displays on the horizon.  This is due to the inherent weakness in blue OLED materials, as confirmed to me by Professor Ching Tang, the inventor of OLED technology.  He said that the energetics involved in blue quantum excitation was at just at the right level to break the bonds in the OLED materials which means that there’s no solution in the forseeable future for improved blue OLED efficiency.

Can OLED displays extend beyond 440 PPI?  Only time will tell.

Galaxy S3 beats iPhone5 for best device of 2012 according to Lindsey Turrentine of CNET.

http://cnet.co/YWpaBX

After reviewing  the 10 best and most influential tech products of the year CNET found the Galaxy S3 as the leader and “worldwide hero”.  She specifically cited the large, vibrant HD display as a key attribute.  This phone uses a 300PPI HD PenTile RGBG OLED display.

It seems that all that I am able to blog about this week are industry pioneers who have passed away. Perhaps this has more to say about the maturity of our industry then about the health of our contributors.  There was a nice writeup in Forbes http://onforb.es/TxgI34

Hill started out as a newspaper writer for 20 years in Scotland. In 1986 he joined Aldus to work on the development of their PageMaker layout program. He moved on to work at  Microsoft in 1994 to run its typography group and left Microsoft in 2009 to work on screen-reading projects. He died last Wednesday of a sudden heart attack.  He will be most remembered for his contributions in the development of ClearType, the application of subpixel rendering to the display of fonts.  It is difficult to imagine anyone who has not had the use of ClearType in today’s world.

Without question Bill Hill will be one of those people who so many will miss.

On November 13^th the digital imaging industry lost one of the key pioneers, Bryce Bayer, who died in Bath, Maine at the age of 83.  http://bit.ly/Tq3jOT While working at Kodak he understood the key issues associated with digital cameras even before there were any digital cameras.  He used his knowledge of human vision to design a color filter layout for imaging sensors that more closely mimicked how the human vision system perceived images to more efficiently capture higher resolution images.  Our eyes primarily see luminance in green and resolve primarily through the modulation of luminance, rather than chrominance.   By developing a layout of filters that populated colors in ration of 25% red, 50% green, and 25% blue it was possible to emulate the manner in which the human vision system primarily uses luminance to resolve details.  The layout he used is shown below:

Bayer color filter pattern

Today this layout is universally used in all digital still cameras and smartphone cameras to enable ultra-compact cameras to capture images that are far better than would have otherwise been possible.  We owe Bryce Bayer an enormous debt of gratitude for his fundamental inventions in digital imaging and digital photography.  No doubt he will be missed by many.

Samsung Galaxy Note Superbowl Ad

With all of the focus on the Superbowl and the Superbowl ads it was gratifying to see two ads for PenTile equipped products in a single Superbowl.  One was for the Galaxy Note with a 5.3-inch diagonal 800 x 1280 format PenTile OLED display http://bit.ly/yW5brS  The other ad was for the Motorola RAZR with a 4.3-inch qHD format PenTile OLED display. http://huff.to/wqqHYr

By my count today PenTile has shown up in 118 products to date.