feb15
OLED vs. LCD not like LCD vs. CRT… The CRT was the dominant display technology for nearly 100 years. There were, of course, other displays such as Vacuum Fluorescent, Electroluminscent, Projection, and Plasma. But the CRT was the “king of the hill”. As CRT technology evolved it became the only technology that could produce video images in full color. It created and dominated the television market for many decades. Then in the mid-sixties along came Liquid Crystals – a really poor display technology by any measure. Displays made with Liquid Crystals were temperature sensitive, slow to respond, barely readable with poor contrast, and difficult to address with all the rows and columns. It appeared that at best LC technology might find a home in simple and small displays such at those for wristwatches and calculators. But gradually one-by-one the problems that were limiting LC performance began to be solved. New LC materials were developed with less temperature sensitivity and faster response. New ways of controlling LC molecules were discovered. Color filters were added and better ways of backlighting were developed. However, the major driving force that propelled intense effort to develop LC technology was the introduction of the laptop computer in the early 90s. There was no other way to make a laptop than with an LC display. Clearly, CRTs were too bulky, plasma displays could not be made that small, and EL was not able to produce full color. As LC displays captured the markets for all small, and now medium size, displays this provided the base on which to build an infrastructure that encouraged further development. However, while all this was going on, manufacturers of CRTs did not feel threatened because they were confident that LC displays could not compete on image quality and that they were destined to sizes that did not exceed 20 inches. The conclusion was that in larger sizes LCDs would always be too expensive because they had to rely on semiconductor-like manufacturing processes. Of course, now we know that this conclusion did not hold up. In the first decade of the 21st century, LCDs grew to dominate all sizes of displays and the CRT was doomed to rapid obsolescence. It is my opinion that the CRT manufacturers underestimated how important flatness and lower weight would be in driving consumer behavior. The prevailing opinion was that since the CRT still produced a better image with faster response that this would be the primary determinant that consumers would use in making their purchasing decisions. However, at the larger display sizes above 30-inch diagonals, CRT televisions were seriously bulky and weighed over 100 pounds. Furthermore, CRTs were limited to sizes no larger than 36 – 40 inches because that was the largest size TV that would fit through a residential door. And at those sizes the weight approached 200 pounds. The elegance of flatness and portability overcame any small remaining defects in image quality. Even plasma technology could not keep up. As LC displays became the technology of choice for virtually all sizes, the manufacturing capability improved with better images and lower cost. By now, LC Displays can be considered a mature technology. Virtually all consumers have purchased a flat-panel TV and the quality of the images is excellent and can match and even exceed the best that was available from a CRT. Given the tremendous success that has been enjoyed by LC displays over the last several years the question then becomes, what’s next? Is there another display revolution on the horizon that would match the “great conversion” from CRTs to LCDs? Some in the display industry had the dream that introduction of 3D technology would create another major conversion. To anyone who took a careful look that was doomed to failure from the very start. The inherent defects with stereoscopic 3D viewing and the need for polarizing glasses did not bode well for having this be the next great technology era. With 3D not happening, some are now proposing that OLED technology will become the next major improvement to drive flat panel sales. While OLED technology may indeed provide some noticeable benefits in image quality, it will not become a driving force such as happened with the transition from CRTs to LCDs. There is no great impetus for converting to an OLED display such as the laptop provided for LC displays and that the bulk of the CRT provided for LCD television. OLED displays provide a modest improvement. They have done the best where battery power is a major concern such as for cell phones. OLED displays will have to become cost competitive with LCDs for larger displays to be considered a displacing technology. Right now that appears to be a major challenge and it is not yet clear how it will be resolved. The next generation of television displays will be driven by the move to higher resolutions such as 4K and UHD TV. It is most likely that for the next several years the needs for higher resolution will be met by the already mature LC technology. OLED technology will have to work hard to exceed what LCDs can do. There should be no expectation that OLED will be the driving force behind another major conversion such as we saw when CRTs were abandoned for LCD flat-panels. Should you wish to offer your thoughts on this topic or others, you may reach me directly from this site, by email at silzars@attglobal.net, or by telephone at 425-898-9117.