Question

Differentiate between joystick and light pen

Answer 1

A light pen is a pen shaped device. It is held in hand and can detect the presence or absence of light with the help of photo electric light with the help of photo electric cell mounted at its front end. Its other end is connected to a computer terminal by means of cable. It sends electrical signal along the cable which indicates whether or not light of sufficient intensity is being sensed. The light pen has an advantage that it eliminates the need to type the input. For example on moving the pen across a bar code, it can directly be fed the data into the computer. Also input by a light penis after than that given by using keyboard. Its disadvantage is that it can detect only the presence or absence of light and also works only with the software written for it. 

A joystick is another input device. With the help of a Joystick, a user can control the movements of objects on the screen by maneuvering a small lever in any direction around its zero position. Usually the Joystick has buttons which can be used for carrying out actions. Joystick is very useful for controlling objects in computer games. In fact the function of a joystick and mouse is similar.