INPUT DEVICE

INPUT Device

In computing, an input device is any peripheral (piece of computer hardware equipment) used to provide data and control signals to an information processing system such as a computer or other information appliance. Examples of input devices include keyboards, mice, scanners, digital cameras and joysticks.

example of input device :

        Mouse

An object used as a pointing and drawing device. The mouse usually has a ball and buttons and is connected to the system unit through serial port. As a mouse is rolled across the flat desktop in any direction, it locates the pointer correspondingly on the screen. Then it issues commands using the selection buttons on the mouse. Many portable microcomputers such as lap-tops use track balls instead of mice.

Touch Screen

A touch screen is a monitor screen that allows users to interact with a computer system by touching an area of the display screen. The screen is covered with a clear plastic layer that has a matrix of cells. A user touches a graphic button that displays option on the screen. Touch screens are easy to use. Thus, many kiosks use touch screens as input forms.

Light Pen

A light pen is a light-sensitive pen-like device used by pointing it at the display surface. A user brings the light pen to the desired point on the screen and presses a button, causing it to identify the current location. It is used to select options from a menu or to draw images.

Digitizer Tablet

A digitizer tablet is also called a graphics tablet or just a digitizer. The digitizer is a drawing tablet used to sketch new images or trace old drawing or photograph. The user uses a pen-like device called a cursor to draw images. Designers and architects usually use digitizers. Light pen and digitizer technologies are used for pen-based computing.

Scanner

A scanner is a device that reads spatial pattern such as images, graphics and texts, and then generates digital signals of that pattern. Converted digital data may be processed by a computer, stored in a disk, printed by a printer or displayed on a monitor. Scanners are commonly used to capture graphic images that can then be placed in a page or on any document.Scanners usually include optical character recognition (OCR) software so that scanners can read and capture texts directly through optical scanning.

Bar Code Readers

A bar code is a specialized code represented by sets of parallel bars of varying thickness and separation. This is used for fast identification of items with an optimal scanner. The optical scanner is called a bar code reader. The bar code reader is a photoelectric scanner that read the bar code.

Magnetic Data Entry

There are two technologies in magnetic data entry. A magnetic ink character recognition (MICR) technology reads iron oxide ink preprinted or encoded on checks, deposit slips or on documents. An MICR reader electronically captures data, by first magnetizing the magnetic ink characters and then sensing the signal.
Another form of magnetic data entry is the magnetic stripe technology that makes computers read credit cards. The dark magnetic stripe on the back of credit cards is the iron oxide coating. A magnetic stripe reader reads this magnetic stripe.

Voice Input Devices

Voice input devices are also called speech- recognition devices or voice-recognition systems. This device uses a voice recognition technology that converts a user's speech into a digital code. Spoken words are first digitized and then matched against a dictionary of patterns previously stored in the computer.
Speaker-dependent systems should be trained by taking actual user's word sample before using, but speaker-independent systems can recognize only limited vocabularies. The advantage of the voice input systems is that they enable users to keep their hands free for other tasks.