摘要 |
The wireless computer input system uses a pen-type input device and a receiver. The pen-type input device includes a LED, at least one switch, a rechargeable battery, and a control circuit. The control circuit provides signals to the LED upon activation of the switch, and provides for power management functions allowing the pen to conserve power during idle periods. The receiver includes one or more light-detecting elements connected to position computation circuitry. The light-detecting element or elements are either a two-dimensional PSD, two one-dimensional PSDs or a four division photodiode. Optional lenses, optical filters, and apertured plates are positioned before the light-detecting element(s), improving the signal-to-noise ratio of the system. The computation circuitry receives the signals from the light-detecting element(s), digitizes them, and computes the coordinates of the pen which are output to a host computer. A recharging circuit, connected to the computation circuit, allows the pen to be recharged within the receiver or connected by a cord when the battery lacks sufficient power. |