文档介绍：INPUT DEVICES
AND OUTPUT DEVICES
Speaker
- Output device
- The presiding officer in a legislative assembly, esp. the House of Representatives
Scanner
- A device for examining, reading, or monitoring something, in particular
- Output device
Concept keyboard
- Input device
- Overlay keyboards are often used as a quick and easy way to input items with just two buttons.
Trackerball
- Input device
- A trackball is a pointing device consisting of a ball held by a socket containing sensors to detect a rotation of the ball about two axes--like an upside-down mouse with an exposed protruding ball.
Optical mark
- Input device
- Many traditional OMR devices work with a dedicated scanner device that shines a beam of light onto the form paper.
recognition (OMR)
- Input device
- Input device
- The contrasting reflectivity at predetermined positions on a page is then used to detect the marked areas because they reflect less light than the blank areas of the paper.
Plotter
- Output device
- The plotter is puter printer for printing vector graphics .
MICROPHONE
- Input device
- An instrument for converting sound waves into electrical energy variations, which may then be amplified.
Biometric Scanners
- Input device
- Biometrics is used puter science as a form of identification and access control. It is also used to identify individuals in groups that are under surveillance.