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Staro 05.06.2008., 15:53   #7
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Datum registracije: Dec 2004
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Ma LED je ok, ali nije neka značajna razlika između toga i klasičnih CCFL cijevi, tek u nešto većem gamutu (u teoriji), no uniformnost pati zbog problema sa starenjem dioda i potencijalnih "crnih rupa".

LED je dostupan kod zaslona prijenosnika tipa Macbook Air i Lenovo X300, no neznam hoće li i kad doći na tržište desktopa kao mainstream osvijetljenje za LCD monitore.
U prijenosnika je plus što ne zauzima puno mjesta, manje se grije i troši manje struje.


Evo izvadak iz wikipedije:

Usage

LED backlighting is most commonly used in small, inexpensive LCD panels. The light is usually colored, although white LED backlighting is becoming more common. ELP backlighting is often used for larger displays or when even backlighting is important; it can also be either colored or white. An ELP must be driven by relatively high voltage AC power, which is provided by an inverter circuit. CCFL backlights are used on large displays like computer monitors, and are usually white in color. These also require the use of an inverter and diffuser. Incandescent backlighting can be used when very high brightness is desired, but a drawback is the limited life of incandescent bulbs, and the amount of heat generated, which often means that the bulb needs to be mounted away from the display.

LED backlighting in larger displays is a recent innovation that helps to improve the color gamut of the LC display. LED white light is created by three separate LEDs to produce a color spectrum that closely matches the color filters in the LCD pixels themselves. In this way the filter passband can be made more narrow, so that each color component lets only a very narrow band of spectrum through the LCD. This improves the efficiency of the display since little light is blocked when white is displayed. Also, the actual Red, Green, and Blue points can be moved farther out so that the display is capable of reproducing more vivid colors. Many current LCD TVs can generate only 70-80% of the colors specified in the NTSC specification while newer displays based on LED backlights will be able to generate all the colors in the NTSC specification plus some additional colors.

[edit] Challenges

However, there are challenges with LED backlights. Good uniformity is harder to achieve especially as the LEDs age with each LED possibly aging at a different rate. Also the use of three separate light sources for Red, Green, and Blue means that the white point of the display can move as the LEDs age at different rates. Power also can be a challenge. Though it is possible for an LED display to be more power efficient, this is not a given and many first generation implementations may use the same or more power than their CCFL counterparts.

[edit] LED backlights on the rise

The usage of LED backlights on notebooks has been growing and is set to increase in 2008. Sony has used LED backlights on some of its higher end slim VAIO notebooks since 2005. Fujitsu has also introduced notebooks with LED backlights in 2006. As of 2007, Asus, Dell and Apple have also introduced LED backlights into some of their notebook models, and other companies like HP will also be marketing LED backlit notebooks in the near future.
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