TV backlight is located behind LCD panel, providing light for image display. LCD panel doesn't produce light itself, requiring external illumination. Backlight technology has evolved significantly over decades
Electric lighting replaced candles and gas lights in early 20th century. Volta created first electric battery in 1799-1800. Warren de la Rue invented first electric light bulb in 1840. Edison and Swan independently developed functional incandescent lamps in 1870s. Coolidge introduced tungsten filament in 1912
First battery-powered flashlights appeared around 1899 with dry cells. David Misell patented the first flashlight in 1899. LED flashlights replaced incandescent bulbs in early 2000s
Power consumption measured using Kill-A-Watt meter with checkerboard pattern. Tested in SDR with local dimming disabled and HDR with maximum brightness
LCD is the most common flat panel display type. LED displays use LEDs as backlight, available in Edge-Lit and Direct-Lit variants. IPS is a panel technology, offering higher image quality than TN and VA
Basic LED setup requires LED, power supply, and resistors. Radioshack offers various LED voltages and power supplies. LEDs come in different sizes, brightnesses, and voltages