4-Input and Output Devices

CRT Monitor

(Cathode ray tube) generally the cheapest form of monitor. They are also the oldest and are extremely chunky. Output device

MICR

(Magnetic ink character recognition) It helps the reader to 'see' the shapes of the characters clearly.The characters can be read by humans as well as the programme. The numbers on the bottom of a cheque are printed using magnetic ink so that they can be read by a special reader even if they have been written over

OCR

(Optical Character Recognition) If a scanned image contains text, you can use software to turn it into text that can be used by a word processor. OCR is helpful for Blind people or for passports scanned!

OMR

(Optical Mark Reader) A scanner can also be used to scan sheet of paper looking for marks on the paper, such as multiple choice.

TFT Monitor

(Thin Film Transistor) These screens have a similar size display area, but the they are far thinner and lighter than the CRT monitor. (Output device)

Bar code reader

A bar code reader is a set of short parallel lines in contrasting colours, often black and white. Bar codes are read by devices that shine a laser at them and then read the reflection to tell how the thick lines are.

Multimedia Projector

Are devices that can project an image from a computer onto as large a surface as is necessary.

Qwerty Keyboards

Gets its name from the arrangement of letter on the top line of keys.

Flatbed plotter

Have the pen lying flat under the pen,

Plotters

They are line-drawing devices.

Inkjet printers

They work by squirting ink at the page out of different nozzles for different coloured ink.

Dot matrix printers

Use a set of pins to press an inked ribbon against paper.

Laser Printer

Work by using a laser to draw the required output onto a drum.

An optical mark reader is used for reading and inputting pencil marks on a form such as a school register or examination answers; any application involving input of a choice of options

optical mark reader

Concept keyboards

unlike qwerty keyboards, allow the user to decide what each keys should stand for and they can be changed when necessary

What are the types of pointing devices?

A mouse,Touchpad,Trackerballs,Joysticks

Control Application

Sensors and control devices together with the controlling computer make up a control application

Direct Input Systems

Some devices, such as optical mark readers, enable dat to be entered directly, without human intervention. These direct input or direct data entry methods are used when large amounts of similar data need to be entered.

Actuator

The device that turns the computer signal into movement is called actuator.

Manual Input Devices

The devices that are used by people to enter data themselves. Keyboards, pointing devices, cameras, scanners and microphones.

Drum plotter

The paper lies on a drum that spins to drive the paper under the pen while the pen itself moves across the drum.

Graphics tablet

is a very large touchpad. It senses the movement of an object moving over its surface and sends this information to the computer

A trackerball is a pointing device used by people with limited motor skills such as young children or those with disabilities.

trackerball