touchscreen

Question 1

how does resistive screen work?
(eg cash machines)

Answer 1

consists of 2 conductive layers. The top layer is flexible. When the screen is touched the two layers connect completing the circuit.

Question 2

+ of resistive screen

Answer 2

• cheap to produce
• resistant to surface contaminants
• can be activated by nearly every object (eg stylus , finger ,gloved hand)

Question 3

how infrared screen works?
( eg tablets laptops smartphones)

Answer 3

• Infrared rays sent across screen
• sensors capture beams
• rays form grid across screen
• ray is broken by finger blocking beam
• coordinates used to locate touch

Question 4

+ of infrared screen

Answer 4

• excellent image quality
• high precision
• durable
• allows for multiple touches at the same time

Question 5

-of infrared screens

Answer 5

requires bare finger or stylus for activation

Question 6

how capacitive screen works?
( eg large scale commerical displays)

Answer 6

made up of a protective layer a transparent conductive layer and a glass substrate. touching the screen changes the electrostatic field of the conductive layer.
- sensors monitor the electrostatic field
- when touched the electrostatic charge is transferred to finger
- c

Question 7

+ of capacitive screen

Answer 7

• excellent image quality
• unlimited touch life
• scale well

Question 8

-of capacitive screen

Answer 8

sensitive to interference from light, water, snow