Apple has recently been awarded patents for a number (here, here) of microphone/speech recognition patents.
The most descriptive is this patent which was filed in July 2002 entitled "Microphone elements for a computing system". The patent abstract is as follows:
- An improved speech recognition device is provided. The speech recognition device comprises a display with at least two built in microphones and a speech recognition module electrically connected to the display. The speech recognition module uses an algorithm that may take into account the position of the built in microphone on the display. The display may have a first axis of rotation where the microphones may be placed an equal distance from the first axis of rotation.
The application itself explains the difficulties in filtering out background noise from speech for recognition, and describes a technique with "at least two built in microphones and a speech recognition module electrically connected to the display".
Apple has not publically released any displays or computers that incorporate this technology.