Output devices

Output devices

Screens, projectors, printers, 3D printers and speakers: what each one does.

Transcript

A screen is made of tiny pixels. An L C D screen uses liquid crystals to block or pass light, and an L E D screen uses light emitting diodes as its backlight.

A projector shines a bright light through a small image, onto a wall or screen. An L C D projector uses liquid crystal panels, and a D L P projector uses thousands of tiny mirrors.

An inkjet printer sprays tiny drops of liquid ink onto paper, which suits photos. A laser printer draws the page on a drum with a laser, then fuses toner powder to the paper with heat. It is fast, and good for lots of text.

A three D printer builds a solid object, layer after layer, from a plastic or resin, following a digital model.

A speaker turns an electrical signal into sound, by vibrating a cone. An actuator turns a signal into movement, for example a motor that opens a door.

Screens and projectors show. Printers make things on paper, or in plastic. Speakers and actuators make sound, and movement.

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