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Edward V Hardway Jr, William H Holtman: Activity and respiration monitor. Cavitron Corporation, Kenneth Olsen, Philip Sperber, July 5, 1977: US04033332 (71 worldwide citation)

A contactless activity and respiration monitor is described which includes a resilient, capacitive pad, which may be a mattress, or a pad used with a mattress, having a capacitor therein responsive to the activity or respiration of a body lying on it. Electronic capacitance sensing circuitry is disc ...


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