公开(公告)号：US11559216B1

公开(公告)日：2023-01-24

申请号：US15675543

申请日：2017-08-11

Applicant: Apple Inc.

Inventor： Arpit Mehta ,  Guocheng Shao ,  Tobias J. Harrison-Noonan

IPC: A61B5/024 ,  A61B5/00

Abstract: This relates to one or more integrated photodiodes on a back surface of a PPG device. The one or more integrated photodiodes can reduce the gap between one or more windows and the active area of the photodiode(s) to increase the PPG signal strength without affecting the depth of light penetration into skin tissue. In some examples, the photodiode stackup can contact the surface of the windows. In some examples, the photodiode stackups can exclude a separate substrate. In some examples, the photodiode stackup can be deposited on the inner surface of the windows opposite the outer surface of the device. In some examples, the photodiode stackup can be deposited on the back surface and/or outer surface of the device. In this manner, PPG sensors can be included in the device without the need for extra layers and measurement accuracy can be improved due to lower light loss.