An LED-backlit LCD is a liquid-crystal display that uses LEDs for backlighting instead of traditional cold cathode fluorescent (CCFL) backlighting. LED-backlit displays use the same TFT LCD (thin-film-transistor liquid-crystal display) technologies as CCFL-backlit LCDs, but offer a variety of advantages over them. While not an LED display, a television using such a combination of an LED backlight with an LCD panel is advertised as an LED TV by some manufacturers and suppliers. Comparison with CCFL-backlit LCDs Advantages When compared with earlier CCFL backlights, using LEDs for backlighting offers: Wider color gamut (with RGB-LED or QDEF) and dimming range Greater contrast ratio Very slim (some screens are less than thin in edge-lit panels) Significantly lighter and cooler, as much as half the total chassis and system weight of a comparable CCFL Typically 20–30% lower power consumption and longer lifespan Greater reliability Disadvantages Unlike OLED and microLED displays, LCDs cannot achieve true blacks for pixels which are illuminated by the backlight. Some LED-backlit LCDs use local dimming zones to increase contrast between bright and dim areas of the display, but this can result in a "blooming" or "halo" effect on dark pixels in or adjacent to an illuminated zone. This can be considered a disadvantage compared to CCFL-backlit LCDs; however, if the display allows for the local dimming algorithm to be disabled via software, doing so will remove any blooming at the cost of negating some of the display's contrast-enhancing capabilities. LED arrangements LED backlights replace CCFL (fluorescent) lamps with a few to several hundred white, RGB or blue LEDs. LEDs may be edge- or direct-lit: edge-lit (ELED): LEDs form a line around the rim of the screen direct-lit (DLED): LEDs form an array directly behind the screen at equally spaced intervals. May additionally support: local dimming: direct-lit LED clusters (rectangles, rows or columns) are individually controlled full array local dimming (FALD): direct-lit LEDs are individually controlled Additionally a special diffusion panel (light guide plate, LGP) is often used to spread the light evenly behind the screen. The local dimming method of backlighting allows to dynamically control the level of light intensity of specific areas of darkness on the screen, resulting in much higher dynamic-contrast ratios, though at the cost of less detail in small, bright objects on a dark background, such as star fields or shadow details. A 2016 study by the University of California (Berkeley) suggests that the subjectively perceived