Mouse

The mouse is a pointing input device; the successor to the light pen, and predecessor to the touch-pad. In addition to the abilty to point, almost all mice have had one or more buttons, to allow the user to signal the computer when some operation is desired.

With the modern GUI user interface, pointing is a key input form, and the invention of a practical mouse made it viable.

Modern mice often also include a 'scroll wheel', to allow the user to control what is displayed on the screen (the exact effect of rolling the scroll wheel depends on the application).

History

The first mice were invented by Douglas Engelbart of the Augmentation Research Center at the Stanford Research Institute. They had two large wheels, which had horizontal axes of rotation, with the axes at right angles to each other.

They worked, but were not very satisfactory (the wheel which was not being actuated had to be dragged sideways). When the Xerox Alto project at Xerox PARC decided they wanted to use a mouse for a pointing device, Bill English (who had worked with Engelbart) started to work on a new design; Ron Rider came up with a much better basic design which used a ball to pick up motion, but it was still complex and expensive.

When Apple decided to add a mouse to the Apple Lisa, they called in a team at Hovey-Kelley Design, led by Dean Hovey, who produced the modern mouse: the ball is not supported by the mouse (as in the Xerox mouse), but simply rolls on the surface, and sensing shafts, held in contact with the ball by a spring-loaded wheel on the other side of the ball, turn slotted wheels which are monitored by optical sensors.

This design still had issues (it tended to pick up dirt, and needed to get cleaned regularly), so eventually optical mice appeared, which sensed movement directly by reflecting light off the surface they were being moved over.

External links

• How the Graphical User Interface was Invented - covers the history of the mouse in some detail
• Doug Engelbart's Original Mouse
• Mighty Mouse - Hovey-Kelley's work on the Apple mouse
• The Engineer of the Original Apple Mouse Talks
• The Optical Mouse, and an Architectural Methodology for Smart Digital Sensors