主权项 |
1. A transcription module comprising:
a mounting unit adapted for positioning said transcription module over a work surface; first and second acoustical receivers attached to said mounting unit, each acoustical receiver comprising a microphone with a microphone input surface wherein acoustical signals enter to be received by said microphone, said microphone positioned over a corresponding location on said work surface and in close proximity to said work surface, each microphone pointing to said work surface at said corresponding location with the normal to the microphone input surface intersecting said work surface at approximately a right angle, each microphone configured to receive acoustical signals generated by an input device that includes an acoustical transmitter and operating over said work surface, wherein said acoustical receivers do not directly view said input device, and wherein said acoustical receivers are used to measure the location of said input device; and a electromagnetic detector that detects an electromagnetic signal that is synchronized with said acoustical signals, wherein at least one of said acoustical receivers includes a physical sound shield to inhibit the reception of sound signals from sources that are significantly above said work surface. |