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What is the flexible display?

the Thin-film polymers and other flexible materials which appeared in the last ten years will change soon enough our idea of what have to be displays. Producers of a PDA and cell phones will begin to build in the « devices; rolled displays thanks to which users will have an opportunity to study the cards interesting them, schemes or Web - pages on the big screen. Portable computers will have the second display on a reverse side of the case. With its help will become possible to look through the chosen materials, addressing them and at those moments when the computer is switched off.

Prototypes of flexible displays have rather small sizes so far, however already today engineers work on creation of flexible screens with the diagonal of 14 inches. Flexibility giving to traditional types of displays is accompanied by a number of difficulties. The liquid crystal screen with an active matrix consists of two layers of glass and a number of the components placed between them. The layer of thin-film transistors in amorphous silicon is etched on the lower surface of glass where light pixels are formed. The liquid crystal layer acting as a light lock is placed from above. Under the display illumination settles down, and the mechanism of management of a color rendition and polarizers take the place above the display. Creation of the flexible display assumes an exception of illumination and replacement of glass layers with some flexible materials, for example, a film from thin polymer.

Complexity is that liquid crystals of the screen are very sensitive to deformation on a bend. Try to press on the &ndash calculator screen; you will see how figures will begin to blur and the black spot will appear. Therefore experts of a number of the companies develop now alternative technologies which would allow to arrange production of flexible displays. It is, in particular, about technologies reflecting electronic » paper; and organic light-emitting diodes.

Displays on the basis of electronic paper are called bistable as the image on them remains also at power off. The reflecting displays unlike ZhK - screens do not demand illumination and can widely be used out of rooms. The first generation of similar devices is applied as signs, price tags on store shelves, and also elements of the equipment for reading e-books.

Light-emitting diodes radiate light independently. They consume more energy, than today`s ZhK - displays with an active matrix, but differ in the increased speed and brighter paints. However to build in light-emitting diodes a flexible substrate - difficult task.

Anyway, today flexible displays still are either in a design stage, or at a stage of creation of a prototype. It belongs both to electronic paper, and to devices on the basis of light-emitting diodes. However development of such technologies will open a set of new ways of development of electronic devices. For example, there will be a possibility of creation of very small devices with the big starting screens. Release of batches is planned to be organized at the beginning of 2007. Flexible screens will be used as additional in cell phones or in the graphic tablets intended for input of information.

At production of flexible screens developers plan to address the processes of an inkjet printing and stratification which succeeded technologies of a vacuum dusting and photolithography. The press on thin polymeric sheets allows to achieve higher efficiency of the automated procedures in comparison with the discrete production technologies applied at production on the conveyor of separate silicon chips. Electronic schemes can be applied on the continuous belt of polymeric sheets by means of procedure of the press with rolled giving and acceptance.

Procedure of the press on the basis of rolled processing allows to reduce considerably prime cost and to achieve reasonable price even for disposable displays. Potential opportunities for production economy are very big. However to get in line to the local supplier of a stationery to buy from him cartridges with organic ink and polymeric sheets on which your inkjet printers will print electronic schemes, still too early.

On the other hand, so far as already today transistors for flexible displays can be applied on substrates by means of technologies of an inkjet printing what prevents us to build in the same polymeric leaf and other electronic components or maybe computer devices entirely? Creation of flexible   devices; - only matter of time. Everything will be defined by speed of rapprochement of portable computers and wireless phones with the PDA functions.

In process of expansion of a range of the electronic devices printed on a polymeric substrate their integration into screens of phones which will get certain relief outlines is possible or will even be able to brag flexible, suitable for carrying on a body or on clothes of a design.

The ultimate goal consists in receiving material for production of easy displays which can be curtailed into a tubule and which are equipped with all necessary electronic components of the next generation, including the processor and memory.

To construct the full-fledged personal computer on a flexible substrate it is difficult, but from the technical point of view, quite perhaps. The researches in the field of flexible electronics connected with memory production were already conducted. And though soon microprocessors of this sort will hardly appear in the market, however we will see other components surely.