Thin film transistor liquid crystal display (TFT-LCD) is a variant of LCD which uses thin-film transistor (TFT) technology to improve image quality. TFT LCD is one type of Active matrix LCD, though all LCD-screens are based on matrix addressing. TFT LCDs are used in television sets, computer monitors, mobile phones, handheld video game systems, personal digital assistants, navigation systems, projectors, etc.