Software dims backlight LEDs when necessary to boost contrast

Sound technology specialist Dolby has moved into display technology, showing software that can boost the contrast on LCD screens.

The most obvious result is that screens can render what appears to be true black, according to an EE Times reporter who saw a demo at the company's New York office.

Conventional LCD displays render black poorly because the can never completely block out the backlight in individual pixels.

Dolby's High Dynamic Range technology exploits the fact that light-emitting diode (LED) backlights, used on many modern displays, can be controlled individually just like pixels. So when a black is required the illuminating LED can be dimmed as well as the pixel.

The system, first announced at Cebit, was demonstrated this week on a 46in panel, illuminated by 1838 LEDs, from Italian home-theatre manufacturer SIM2. Dolby claims it has a contrast ratio of up to eight times that of a normal LCD.

The HDR processing was done on a PC for the purposes of the demonstration but it is to be implemented on a custom cjhip to be fitted into TVs, says EE Times.