The Passive Matrix LCD(PMLCD) is the simplest and cheapest graphic LCDs to make. The PMLCD uses a simple grid type adressing of each pixel. The buildup of a PMLCD is similar to other LCDs. The two glassplates are given lines of transparent electrodes made from indium-tinoxide. One is given horisontal lines, the other vertical. These rows and columns are then connected to the driver/control electronics.

This kind of display is OK for two shade monochrome displays. They need less power than Active Matrix LCDs(AMLCD), and are therefore often used in graphic calculators and B/W PDAs. But has a slow update rate and due to relatively high resistance in the transparent electrodes, the accurate voltage control neaded for grayscale is hard. On older, cheaper laptops this LCD type is used. It's easy to identify a PMLCD on a laptop since the slow updates makes a ghostimage or fading effect on fast moving objects(like a mouse pointer), and due to the voltage control problem, a change in one pixel may lead to a small but detectable change in intencity of the entire row or coloumn. Therefore most modern PC LCDs uses active matrix technology.

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