The Future of Television Displays

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The future of Digital Technology 

OLED (organic Light-emitting diodes) 

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Imagine a cardboard thin TV screen.  Now imagine rolling up your TV screen and storing it in a closet or putting it in your briefcase and taking it with you.  This will soon be a reality through OLEDs or organic light-emitting diodes.  OLED technology exist today and can be seen in its use of some mobile phones, MP3 players, car radios and even in some digital cameras.  But on October 1st, 2007, Sony became the first company to announce an OLED television.  The XEL-1 11" OLED digital television sells for around $2500 in Canada as of April 24, 2008 (although it was really more of a prototype).  You can't roll this television up just yet.  But manufactures hope that possibility isn't too far away.     

This new display technology promises to deliver thin, power efficient and bright displays.  The biggest difference between the traditional liquid crystal displays, LCDs and OLEDs is OLEDs don't require a backlight to function.  Since there is no need for a backlight, it allows OLEDs to be much, much thinner than a LCD panel.  Another advantage of the OLED is that they use up far less power.   OLED technology is based on light-emitting diodes made from polymers as well as from semiconductors with a series of organic thin films between two conductors.  When an electrical current between the layers is added it will emit a very bright light.  This is called electro phosphorescence.  The polymer materials are applied in rows and columns onto a flat carrier (glass, plastic or even fabric) by a simple, yet precision ink jet printing process. The resulting matrix of pixels can emit light of different colors.  Using this technology, pixels of red, green, and blue material are applied. 

Since the manufacturing process of this the new technology is simple, requiring a very limited number of process steps compared to other television manufacturing processes while using fewer materials, it can be manufactured at a much lower cost.  The whole display can be built on one sheet of glass or plastic.  This technology will enable the production of full-color displays less than 1 mm thick, combined with a large viewing angle, high brightness and contrast and full video capability.   

The drastically different manufacturing process of OLEDs lends itself to many advantages over flat-panel displays made with LCD technology. Since OLEDs can be printed onto any suitable base material using an inkjet printer or even screen printing technologies, new applications such as roll-up displays and displays embedded in fabrics or clothing are now a real possibility.

These systems are ideal for use in not only televisions screens but also laptops, stereo displays, car navigation systems (which is seen today) and even billboards and roar signs.  The possibilities are literally endless.  OLEDs can also be used for a general light source for space illumination and large-area light-emitting elements. OLEDs typically emit less light per area than inorganic solid-state based LEDs which are usually designed for use as point-light sources. There are a few drawbacks to the new technology.  

The biggest problem for OLEDs is the organic materials do have a limited lifetime.  For example, blue OLEDs traditionally have a lifespan of around 14,000 hours.  Broken-down that is roughly 5 years at 8 hours a day.  The typical lifespan of the LCD is around 60,000 hours.  Another issue is that the slightest amount of water can destroy the organic materials so the sealing process are important for practical manufacturing.     

OLED pixel colors appear correct and unshifted, even if one was to view the display from a 90 degree angle.  Since OLED pixels directly emit light, it enables a greater range of colors, brightness, and viewing angle as compared to LCDs.  While LCDs use a backlight and cannot show true black, an "off" OLED element produces no light and consumes no power.  LCDs also waste more power than OLEDs because they require polarizerís which filter out about half of the light emitted by the backlight.  

The possibilities are endless with OLED technology.  Reports show that by 2009 people may start to see this technology begin to pop-up on a consumer level.  10 to 14 inch laptop screens are expected to be among the first round of  consumer based ìdisplayî products open for the publics consumption with more commercial products hitting shelves by 2011.   

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Bibliography 

http://www.oledinfo.com/oledTV

http://electronics.howstuffworks.com/oled.htm

http://ces.cnet.com/8301-1_1-9842035-67.html

http://www.wave-report.com/tutorials/oled.htm