passive matrix These basic flat-panel displays are created by laying a layer of liquid-crystal diode elements on top of a grid of wires. By applying current to the various intersections, the diodes can be lit to act as pixels. Passive displays simply apply current to the diodes at a specific refresh rate to maintain an image. Higher-quality (and, therefore, more expensive) active-matrix or TFT displays control each diode with one or more transistors, making for sharper, brighter pictures. See also: active matrix, flat-panel display, LCD, persistence, refresh rate, TFT