04305401 is referenced by 51 patents and cites 6 patents.

A digital watch has a face mounted local pulse sensor unit which is coupled to infrared plethysmograph electronics within the watch. The local pulse sensor includes transmitter and receiver photodiodes connected to the electronics by a plurality of moveable contact fingers. A connector at one end of a flat cable is insertable into a slotted opening on the side of the local pulse sensor and between the contact fingers and the two local photodiodes to disconnect the photodiodes from the electronics. Simultaneously, a remote pulse sensor unit at the other end of the cable is electrically coupled to the contact fingers by the connector for enabling the wearer's pulse at his finger to be sensed. A loop about the connector end of the cable maintains the connector in position when inserted into the local pulse sensor receptacle. A cuff at the remote sensor end of the cable secures the sensor to a wearer's finger for pulse monitoring.

Title
Digital watch/infrared plethysmograph having a quick release remote pulse sensor having a finger cuff
Application Number
6/39531
Publication Number
4305401
Application Date
May 16, 1979
Publication Date
December 15, 1981
Inventor
Rudolf F Zurcher
Newport Beach
CA, US
Manfred W Reissmueller
Orange
CA, US
Agent
W H MacAllister
Lewis B Sternfels
Assignee
Hughes Aircraft Company
CA, US
IPC
A61B 5/02
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