Which of the following is used as "Input device" for the computer?
Which of the following is used as "Input device" for the computer?
The correct option is E Light pen
Light pen is used as "Input device" for the
computer
A light pen is a computer input device in the form of a
light-sensitive wand used in conjunction with a computer's CRT display.
It allows the user to point to displayed objects or draw
on the screen in a similar way to a touchscreen but with greater positional
accuracy. A light pen can work with any CRT-based display, but its ability to
be used with LCDs was unclear (though Toshiba and Hitachi displayed a similar
idea at the "Display 2006" show in Japan
A light pen detects changes of brightness of nearby
screen pixels when scanned by cathode ray tube electron beam and communicates
the timing of this event to the computer. Since a CRT scans the entire screen
one pixel at a time, the computer can keep track of the expected time of
scanning various locations on screen by the beam and infer the pen's position
from the latest timestamp.
Light pen is used as "Input device" for the computer
A light pen is a computer input device in the form of a light-sensitive wand used in conjunction with a computer's CRT display.
It allows the user to point to displayed objects or draw on the screen in a similar way to a touchscreen but with greater positional accuracy. A light pen can work with any CRT-based display, but its ability to be used with LCDs was unclear (though Toshiba and Hitachi displayed a similar idea at the "Display 2006" show in Japan
A light pen detects changes of brightness of nearby screen pixels when scanned by cathode ray tube electron beam and communicates the timing of this event to the computer. Since a CRT scans the entire screen one pixel at a time, the computer can keep track of the expected time of scanning various locations on screen by the beam and infer the pen's position from the latest timestamp.
