1. Field of the Invention
The present invention relates to a pointing device for a computer system with inertial click-event detection and to a corresponding click-event detection method.
2. Description of the Related Art
As is known, most computer systems and computer-controlled devices are provided with pointing peripherals that enable commands to be imparted and a high number of operations to be executed in an extremely simple and intuitive way. In particular, the mouse is now the most common interface between a user and a computer and is manually displaced on a plane or on a two-dimensional surface for controlling a cursor or pointing element displayed on a screen. For this purpose, the typical mouse has a plurality of sensors that detect a movement in two dimensions of the mouse, a plurality of keys for entering commands, and a communication interface for communicating with the computer system.
In a conventional mouse, the keys actuate normally-open electromechanical switches so as to modify the state of a recognition circuit, and are controlled directly by the user's fingers (usually, the index finger and the middle finger). In use, the mouse is held by the user in his hand, and the fingers rest on the keys, which are actuated by exerting a slight pressure. To facilitate recognition of voluntary acts by the user, the keys are triggered only if a sufficient force is applied, higher than a pre-set threshold. Since triggering produces a sound event, actuation of a key is typically defined as “click” or “click event”.
A drawback of traditional pointing devices is that the contacts of the switches, with time, tend to oxidize, and hence electric-type detection of the click events fails. Clearly, this problem renders unusable traditional pointing devices and limits their average life.