The Silent Sound Technology uses electromyography, monitoring tiny muscular movements that occur when we speak.
Electromyography (EMG) is a technique for evaluating and recording the electrical activity produced by skeletal
muscles. EMG is performed using an instrument called an electromyograph, to produce a record called an
electromyogram. An electromyograph detects the electrical potential generated by muscle cells when these cells are
electrically or neurologically activated.
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Monitored signals are converted into electrical pulses that can then be turned
into speech, without a sound uttered. It is a technique which monitors tiny muscular movements and pulses generated
by it. The transducers involved converts the pulses into electric signals. The electrical source is the muscle membrane
potential of about -90mV.
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Measured EMG potentials range between less than 50 μV and up to 20 to 30mV,
depending on the muscle under observation.
As shown in Figure 2 the electromyography sensors attached to the facerecords the electric signals produced by the
facial muscles, compare them with prerecorded signal pattern of spoken words.