Granted Patent
B1
US 12,575,773 · App. 18/793,155 · Granted Mar 17, 2026
Photoplethysmography sensors and processes
Inventors:
Brennan Torstrick (Atlanta, GA); Christopher Lee (Atlanta, GA); Yanni Angelides (Atlanta, GA); Mohsen Safaei (Atlanta, GA); Claire Parnell (Atlanta, GA); Don Griffin (Atlanta, GA); Donald Mock (Atlanta, GA)
Assignee:
HUXLEY MEDICAL, INC.
View Patent ↗
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Abstract
The present disclosure relates to devices and processes that produce superior photoplethysmography (PPG) signals. In various embodiments, the present devices and processes leverage load backing, conformal contact, and strain isolation mechanisms to produce higher quality and amplitude PPG signals, and provide more repeatable results than previous devices and processes. In at least one embodiment, the devices discussed herein include a rigid support structure and elastic spacer for supporting a PPG sensor and various adhesive layers.
Claims (48)
1 . A method comprising:
preparing skin of a patient for attaching a patch;
removing backing from the patch to expose a first adhesive and a second adhesive for attaching the patch to skin of a patient, the patch comprising:
a photoplethysmography (PPG) sensor;
a first area proximate the PPG sensor;
a second area comprising a rigid support structure backing at least a portion of the second adhesive, the second area surrounding the first area;
an elastic spacer operatively connected to the rigid support structure and the PPG sensor; and
a vertical distance between a bottom of the patch and the PPG sensor;
translationally and rotationally locating the patch on the patient based on at least one alignment feature;
pressing the PPG sensor into the skin of the patient by affixing the patch to the skin of the patient via the first adhesive and the second adhesive, wherein:
pressing the PPG sensor into the skin of the patient results in a force applied to the PPG sensor against the skin of the patient;
the second area strain isolates the PPG sensor when the patch is affixed to the skin of the patient; and
the force applied to the PPG sensor and the strain isolation of the PPG sensor mitigates skin strain and maintains skin contact between the PPG sensor and the skin of the patient.
2 . The method of claim 1 , wherein the second adhesive is a stronger adhesive than the first adhesive.
3 . The method of claim 2 , wherein the rigid support structure comprises a cradle for attaching a pod to the patch.
4 . The method of claim 3 , wherein the PPG sensor extends from the pod through an opening defined by the patch and an opening defined by the cradle.
5 . The method of claim 4 , wherein the first area corresponds to the opening defined by the patch.
6 . The method of claim 5 , wherein the patch further comprises one or more electrocardiogram (ECG) electrodes.
7 . The method of claim 6 , wherein the pod comprises a microcontroller operatively connected to the PPG sensor and the ECG electrodes.
8 . The method of claim 7 , wherein the at least one alignment feature comprises an indicator line for rotationally locating the patch along the longitudinal axis of the chest of the patient.
9 . The method of claim 8 , wherein rotationally locating the patch comprises aligning the indicator line along a sternum of the patient.
10 . The method of claim 9 , wherein:
the at least one alignment feature comprises an arc for translationally locating the patch based on the base of the neck of the patient; and
the indicator line extends perpendicular to the arc.
11 . The method of claim 10 , wherein at least one of the one or more ECG electrodes is near or over a sternum of the patient when the patch is affixed to the patient.
12 . A method comprising:
preparing skin of a patient for attaching a patch;
removing backing from the patch to expose a first adhesive and a second adhesive for attaching the patch to skin of a patient, the patch comprising:
a photoplethysmography (PPG) sensor;
a first area proximate the PPG sensor;
a second area comprising a rigid support structure backing at least a portion of the second adhesive, the second area surrounding the first area;
an elastic spacer operatively connected to the rigid support structure and the PPG sensor; and
a vertical distance between a bottom of the patch and the PPG sensor;
locating the patch on the chest of the patient based on at least one alignment feature; and
pressing the PPG sensor into the skin of the patient by affixing the patch to the skin of the patient via the first adhesive and the second adhesive, wherein:
pressing the PPG sensor into the skin of the patient results in a force applied to the PPG sensor against the skin of the patient;
the second area strain isolates the PPG sensor when the patch is affixed to the skin of the patient; and
the force applied to the PPG sensor and the strain isolation of the PPG sensor mitigates skin strain and maintains skin contact between the PPG sensor and the skin of the patient.
13 . The method of claim 12 , wherein the second adhesive is a stronger adhesive than the first adhesive.
14 . The method of claim 13 , wherein the rigid support structure comprises a cradle for attaching a pod to the patch.
15 . The method of claim 14 , wherein the PPG sensor extends from the pod through an opening defined by the patch and an opening defined by the cradle.
16 . The method of claim 15 , wherein the first area corresponds to the opening defined by the patch.
17 . The method of claim 16 , wherein the patch further comprises one or more electrocardiogram (ECG) electrodes.
18 . The method of claim 17 , wherein the pod comprises a microcontroller operatively connected to the PPG sensor and the ECG electrodes.
19 . The method of claim 18 , wherein:
locating the patch on the chest of the patient comprises translationally and rotationally locating the patch on the patient based on the at least one alignment feature; and
the at least one alignment feature comprises an indicator line for rotationally locating the patch along the longitudinal axis of the chest of the patient.
20 . The method of claim 19 , wherein rotationally locating the patch comprises aligning the indicator line along a sternum of the patient.
Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST
Recorded Sep 23, 2025
From: TORSTRICK, BRENNAN; LEE, CHRISTOPHER; ANGELIDES, YANNI; SAFAEI, MOHSEN; PARNELL, CLAIRE; GRIFFIN, DON; MOCK, DONALD
To: HUXLEY MEDICAL, INC.
Reel/Frame 072344/0769 →
Continuity (4)
Continuation
18338888
· Jun 21, 2023
Continuation In Part
17821990
· Aug 24, 2022
Provisional Application
63354119
· Jun 21, 2022
Provisional Application
63236511
· Aug 24, 2021
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