The main difference between LCD (Liquid Crystal Display) and LED (Light Emitting Diode) televisions lies in the type of backlighting used.
LCD TVs have a liquid crystal display panel that blocks or allows the passage of light to create images. They require a separate light source called a CCFL (Cold Cathode Fluorescent Lamp) backlight, located behind the display panel, to illuminate the screen. The CCFL backlight emits a steady light across the entire screen, resulting in less contrast and poorer black levels.
On the other hand, LED TVs also use an LCD panel but employ LED backlighting technology. LEDs are small, energy-efficient, solid-state light sources that can be placed either behind the display panel (direct-lit) or around the edges of the panel (edge-lit). Direct-lit LED TVs offer better picture quality by providing more uniform brightness across the screen and allowing local dimming, where specific areas of the screen can be dimmed or turned off to enhance contrast and black levels. Edge-lit LED TVs, on the other hand, are slimmer and lighter but may not offer the same level of picture quality as direct-lit LED TVs.
In summary, the main difference lies in the backlighting technology. LCD TVs use CCFL backlights, while LED TVs use LED backlights, which can offer better picture quality, improved contrast, and black levels.