Input devices

Question 1

Touch screen work?

Answer 1

There are crisscrossing beams of infrared light in front of the monitor. The computer detects the position of the finger and responds accordingly.

Question 2

What are light pens?

Answer 2

A light pen is a computer input device in the form of a light-sensitive wand used in conjunction with a computer’s CRT TV set or monitor. It allows the user to point to displayed objects, or draw on the screen, in a similar way to a touch screen but with greater positional accuracy.

Question 3

4 uses of webcams

Answer 3

1. Video calling and conferencing
2. Video security
3. Video clips and stills
4. Input control devices

Question 4

Disadvantages of magnetic strip codes.

Answer 4

The cards can easily be damaged, especially by magnets. If this happens the card will no longer be readable.

Question 5

Digital cameras?

Answer 5

Digital cameras have a built-in computer and record images electronically where conventional cameras depend on mechanical/chemical processes to capture images and print it on film or paper.

Question 6

Bar code scanners work?

Answer 6

A bar code consists of a number of black and white stripes of different thickness. A bar code reader reads the light reflected from the dark and light lines. The lines represent numbers and are read by a wand or scanner.

Question 7

Application of OCR?

Answer 7

One application of OCR is reading postcodes on letters when sorting the letters.