US Patent 7995034 Input device having a presence sensor

A system and method for reducing power consumption of a wireless input device is disclosed. The input device may convert between a high power state and a low power state. In the high power state, a transmitter and light sources are activated, whereas both the transmitter and the light sources are deactivated in the low power state. Following a period of inactivity in which neither a key sensor for activatable keys nor a presence sensor for the user transmit input, the input device may convert from the high power state to the low power state to conserve energy. When the presence sensor detects the presence of the user, however, the input converts to the high power state wherein the transmitter and the light sources are activated.