Input Output Ppt

Project on input

Devices

INDEX• DEFINATION OF INPUT DEVICES.

• INPUT UNIT &HOW IT WORKS.

• HOW DOES A INPUT DEVICES WORK.

• CLASSIFACITION OF INPUT DEVICES.

• VARIOUS TYPES OF INPUT DEVICES .

KeyboardThe commonest way to enter data into a computer.

Each key is simply a switch, which when pressed, results in a digital code being sent to the computer.

MICROPHONE /AUDIO DEVICE !!!.

• A microphone, sometimes colloquially called a mic or mike, is an acoustic-to-electric transducer or sensor that converts sound into an electrical signal. Microphones are used in many applications such as telephones, tape recorders, hearing aids.

WEBCAM-image &video input device!!!

• Webcams are mostly used during long distance chatting. There are many uses of it some are positive while some are negative. Webcams typically include a lens, an image sensor, and some support electronics .

MouseThe movement of the mouse over a flat surface is mirrored by a pointer on the monitor screen.

Under the mouse is a ball which rolls and turns two shafts, one for each direction - left/right & up/down.

Touch sensitive screen

This device acts like a mouse that the user can move by touching the screen.

It is used by people who find using a mouse difficult, too time consuming.

Bar code readerThe bar coded item is swiped over a laser scanner is swiped over the bar code to read in the data.

It is the same as a scanner but due to the simple nature of the bar code the scanning is very rapid.

ScannerLike a photocopier it scans a full page with laser light but, it transmits the image to the computer as digital code, which can be saved as a file.

Digital camera

Light received through the lens is converted to digital signals by sensors. The resulting "photograph" can then be stored on a computer and used just like any clipart files.

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OutputOutput

Four common type of output are text, graphics, audio and video.

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OutputOutput

Output Devices

Digital signals from computer are converted into human readable form.

Hard Copy

Soft Copy

Output Devices

Display monitors

Com

Printers

Plotters

Speech Synthesizers

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OutputOutput

CRT Monitors

•Raster scan technology

•An electron beam moves back and forward across the back of the screen

•This causes dots on the front of the screen to glow, producing an image

•Available in various sizes 15 – 22 inches

•Flat and curved screens

Resolution

•CRT monitors ( 1280 X 1024 pixels)

•High end CRT monitors (2048 X 1536 pixels)….

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OutputOutput

LCD Monitors

•An electric current passes through the crystals causing them to twist, block light waves and create an image.

….

Computer Output Microfilm (COM)

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OutputOutput

Printers

Impact printers :- It is the Result of mechanically striking paper medium.

Dot Matrix:

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OutputOutput

Non-impact printers - no physical contact between paper and printing device- 3 technologies used:ink jet :-

Ink droplets are used

thermal - special paper - expensive to run - up to photographic quality…

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OutputOutput

Laser

- need enough memory to hold an entire page - 600 to 2400 dpi and greater- operates similar to a photocopy machine…

Plotters

• Flatbed Plotter

• Drum Plotter

Flatbed Plotters

Drum Plotters

Speech Synthesizers