04033332 is referenced by 71 patents and cites 8 patents.

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 disclosed which provides an indication or alarm in the event of excessive activity or apnea, or low or high respiration rate. Readouts of respiration rate, and number of events of activity may also be provided. Circuits are disclosed for filtering out large static or relatively long term changes in the capacitance of the capacitive pad while maintaining the high sensitivity necessary to sense movements caused by respiration.

Title
Activity and respiration monitor
Application Number
287844
Publication Number
4033332
Application Date
July 21, 1975
Publication Date
July 5, 1977
Inventor
William H Holtman
LaPorte
TX, US
Edward V Hardway Jr
Houston
TX, US
Agent
Philip Sperber
Kenneth Olsen
Assignee
Cavitron Corporation
NY, US
IPC
A61B 5/10
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