Led Backlighting Techniques - Panasonic TC-L42D2 Technical Manual

LED Backlighting Techniques

LED Lights the Way to Better Images, Thinner TVs and Energy Savings.
Introducing LED edge-lit technology to the VIERA® 2010 LCD model line-up. Edge
lighting uses white LEDs arranged around the inside frame of the TV along with a special
diffusion panel designed to spread the light evenly behind the LCD panel. This method of
backlighting the LCD panel allows for the LED LCD HDTVs to become extremely thin and
offers a wider color gamut than traditional back-lit LCDs, which use fluorescent bulbs to
provide the light source. Combined with the IPS panel, the viewing angle is improved,
contrast is better and there is lower power consumption.
LED-backlit LCD TVs are considered a more sustainable choice, with a longer life and
better energy efficiency than plasmas and conventional LCD TVs. Unlike CCFL
backlights, LEDs also use no mercury in their manufacture. However, other elements
such as gallium and arsenic are used in the manufacture of the LED emitters themselves,
meaning there is some debate over whether they are a significantly better long term
solution to the problem of TV disposal in the environment.
Because LEDs are able to be switched on and off more quickly than CCFL displays and
can offer a higher light output, it is theoretically possible to offer very high contrast ratios.
They can produce deep blacks (LEDs off) and a high brightness (LEDs on), however care
should be taken with measurements made from pure black and pure white outputs, as
technologies like Edge-LED lighting do not allow these outputs to be reproduced
simultaneously on-screen.
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