Human heartbeat sensor - photoelectrically measures changes in light transmission of body part dependent on blood flow

摘要

Human heartbeat sensor uses photoelectric sensing of the change oflight transmissibility of a body part in dependence on blood flow through it. Preferably, the periodic and individual alterations in the course of the photoelectric output signal are extracted by conventional electronic e.g. frequency filters. More particularly, this gives an indirect method for medical diagnosis by a simple procedure, which is more accurate than sensing of pressure and does not require undressing the patient since the measurement can be taken at a normally uncovered part, e.g. finger, ear, or any other thin organ. The light source is preferably infrared or of a reddish colour. The body organ is placed between this source and the photoelectric receiver which converts the intensity of light to an electrical potential or current.