Patent ID: 11864877
Assignee: ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE (EPFL)
Field: Audio-visual technology (Electrical engineering)
Classification: CPC A  H | IPC A  H

Claim 8:
9. A photoplethysmography (PPG) sensing device, the device comprising:
a pulsed light source,
at least one pixel for light-to-charge conversion to create photo-generated electrons, comprising:
a pinned photodiode including a well,
a sense node, and
a transfer gate having its source electronically connected to one electronic connection node of the pinned photodiode, and being configured to act as a transfer gate between the pinned photodiode and the sense node to transfer at least part of any integrated photo-generated electrons to the sense node for a read-out;
a first capacitance to store a value of an output signal, when the pulsed light source is off and the sense node well is empty, and a second capacitance to store a value of the output signal, when the pulsed light source is off, and the device is just subject to ambient light, and to store a value of the output signal when the pulsed light source is on.