October 2005 Flexible Displays – Why?…
For over two thousand years we have had flexible displays. From my imprecise recollection of history, it would appear that papyrus roll-to-roll displays were around for quite some time before we decided to put written information onto “pages” in the shapes and sizes that resemble today’s books. Over many centuries, techniques for making these “pages” improved and new uses were found. Gradually, these flexible displays evolved into the variety of useful formats that we see today – books and magazines on paper, signs and banners on cloth and a variety of other materials, and even “wearable” flexible displays such as T-shirts and other articles of clothing.

The one obvious limitation of all these display formats is that they cannot be readily and frequently updated. If we are finished reading a magazine and would like new information, we have to discard the old one and find a place that sells us a new one. Of course this information that we so casually discard is potentially reusable by someone else who has not seen it yet. As for the T-shirt slogans that were so cute just a few months ago, they may no longer fit into the latest fashion or political statement. This leads one to the “obvious” conclusion that a combination of flexibility and change-ability should be something that many of us wish to have.
Some years ago, I was taught in a marketing class that the fundamental path to business success is to “find a need and meet it”. So what could more clearly be a need -- if flexibility is good and change-ability is also good then the two together should be really good? This combination, therefore, surely must meet new needs that neither flexible non-changeable displays nor non-flexible changeable displays can satisfy.

For the moment, let’s accept this premise. Given this assumption we are, however, still left with a “minor” nagging problem. Namely, once we have created our superbly flexible displays, how do we get new information into them? At this stage of our display technology development, the only way we know how to do high-information-content two-dimensional displays, that can be updated with a wide variety of images, is to use rows and columns with the junctures representing the information points we can address. That means that every row and every column must have a connection to it, and this connection must lead to some kind of electronic circuitry that will provide the voltages and currents to put the information into all of the pixels of our flexible display.
With this requirement, our up-to-now elegant display medium has suddenly acquired a complicated umbilical cord. We could, of course, assume that there must be a way to make the electronics also flexible and easy to integrate into or onto the display itself. If we do that, then we will still need a connection to the information source, but the connection will be much simpler.
However, by the time we have added the drive electronics and a power source, such as a battery pack, the promise of a display that will have the look and feel of a piece of high-quality paper is met only if we ignore these extra items needed to make it work. We may also be disappointed that the display does not really look and feel like “real” paper, and that the resolution is limited by the fixed format of the rows and columns.
Nevertheless, if there is a market potential such inconveniences should not get in the way. An excellent example of this is the laptop computer. The early LC displays for these computers were truly awful. They were monochrome with poor contrast and virtually no gray scale. They were slow to respond and had limited resolution. But these rudimentary passive matrix-addressed LCDs were the only way to make a laptop computer. And we all wanted one! Therefore, in spite of all the imperfections, the technology was used and a revolutionary product was successfully brought to market. Is there such an opportunity for flexible displays?
What could be some new applications where flexibility combined with updateable information is so important that we will make use of such a product even in its early stages of development? Hmmm…

Books and magazines seem to be doing just fine in their existing formats. So far all of the attempts to make them “electronic” have not had much success. There is something very convenient and comforting about a book, and the turning of pages gives one a satisfying measure of progress. The cost of the paper medium is so low that buying a new one is not a concern. Posters and banners may benefit from flexibility along with updating capability but it may have to be at a cost that will have to be competitive with conventional printing. And, in any case, that may be a limited market because billboards and other “boards” that are not flexible can provide the desired information content in most applications.

Well then, how about “wearable” displays or displays for portable electronic appliances? We are becoming more and more connected through cell phones and the Internet. But what advantage will we gain from flexibility?

It seems to me that flexibility in itself may not do that much for us. However, suppose you could have a display that is not only flexible but is very thin. Suppose you can have a display that is emissive, i.e. does not require a back light, and that is in addition so thin that it can easily be implemented into all kinds of portable and “wearable” electronic appliances. And suppose that these displays can be scaled up to larger sizes and used almost like wallpaper. Perhaps now, we may be onto something. The interesting answer may not lie in flexibility but in thinness.

Would this satisfy the marketing fundamental of “finding a need and meeting it”? I certainly would not hesitate to consider a business venture that could bring to market displays that are very thin and can be used without additional lighting sources. Some flexibility may be desirable, but perhaps more from the standpoint of ruggedness than for making active surfaces in strange shapes. Flexible displays may yet have an interesting future once we recognize why we really need them and want them. Until then it will be interesting to watch how the various new ventures position themselves to find that magic need that they can try to meet.

I welcome your comments on this topic or any other “flexible” subjects that may stimulate your thinking. You can reach me directly from this web site, via e-mail at silzars@attglobal.net, by telephone at 425-898-9117, or by fax 425-898-1727.