Blood pressure measurement device and method for measuring blood pressure

Patent metadata

Field	Value
Publication number	US-12575746-B2
Application number	US-202318494804-A
Country	US
Kind code	B2
Filing date	Oct 26, 2023
Priority date	Aug 2, 2023
Publication date	Mar 17, 2026
Grant date	Mar 17, 2026

Abstract

A blood pressure measurement device includes a substrate, a protrusion portion, an image sensor, a first light source, a second light source, and a control and processing unit. A plurality of hollow portions is disposed within and enclosed by the protrusion portion. The first light source projects a first light toward the substrate. A finger presses the protrusion portion and the hollow portions, and the image sensor captures an image of a bright area. The control and processing unit determines whether the finger has enough pressure based on the bright area image. The second light source projects a second light toward the substrate, penetrating the substrate and the finger skin to be reflected by a blood vessel. The image sensor captures an image of a changed volume of the blood vessel, and the control and processing unit calculates the systolic or diastolic pressure.

First claim

What is claimed is:

1 . A blood pressure measurement device, comprising:
a substrate; a protrusion portion, disposed on the substrate and the protrusion portion having a plurality of hollow portions formed within the protrusion portion with each of the plurality of hollow portions being enclosed by the protrusion portion; an image sensor, disposed below the substrate and the image sensor corresponding to the hollow portions; at least one first light source, disposed below one side of the substrate; at least one second light source, disposed below the substrate; and a control and processing unit, electrically connected to the image sensor, the at least one first light source, and the at least one second light source; wherein, the at least one first light source projects a first light toward the substrate, and the first light forms a total reflection inside the substrate; when a finger presses the protrusion portion and sinks into the plurality of hollow portions of the protrusion portion to press against the substrate, the total reflection of the first light is destroyed and the first light is reflected by the finger; the image sensor receives a reflected first light and captures a bright area image; the control and processing unit calculates a number of light-receiving pixels (B) based on the bright area image and a number of light-receivable pixels (A) of the image sensor, to obtain a ratio (B/A) % of the number of light-receiving pixels of the bright area image to the number of light-receivable pixels of the image sensor to determine whether a pressure exerted by the finger is sufficient; wherein, the at least one second light source projects a second light toward of the substrate; the second light penetrates the substrate and the skin of the finger and is reflected by a blood vessel; the image sensor receives a reflected second light and captures a blood vessel volume change image, and the control and processing unit calculates a systolic pressure or a diastolic pressure based on the blood vessel volume change image.

2 . The blood pressure measurement device according to claim 1 , wherein when the ratio is between 90 and 98%, the control and processing unit determines that the pressure exerted by the finger is sufficient; when the ratio is less than 90%, the control and processing unit determines that the pressure exerted by the finger is insufficient; and when the ratio is greater than 98%, the control and processing unit determines that the pressure exerted by the finger is too high.

3 . The blood pressure measurement device according to claim 1 , further comprising a reflective layer disposed between the protrusion portion and the substrate, the reflective layer being used to prevent a path of the total reflection of the first light from changing or being destroyed before the first light enters the hollow portions.

4 . The blood pressure measurement device according to claim 1 , further comprising a warning unit electrically connected to the control and processing unit; wherein, when the control and processing unit determines that the pressure exerted by the finger is insufficient or too high, the warning unit sends out a warning signal.

5 . The blood pressure measurement device according to claim 1 , further comprising a uniform sheet light source, disposed above the protrusion portion; wherein the uniform sheet light source projects a third light toward the substrate, and the third light passes through the hollow portions and the substrate in sequence; the image sensor receives the third light and captures an actual bright area image; and the control and processing unit determines an actual number of light-receivable pixels of the image sensor according to the actual bright area image.

6 . A blood pressure measurement method, comprising the following steps:
preparing a substrate disposed with a protrusion portion, the protrusion portion having a plurality of hollow portions formed within the protrusion portion with each of the plurality of hollow portions being enclosed by the protrusion portion; positioning a finger to press the protrusion portion, the finger sinking into the plurality of hollow portions of the protrusion portion and pressing against the substrate; activating at least one first light source to project a first light toward the substrate, the first light forming a total reflection inside the substrate, and the total reflection of the first light being destroyed and the first light being reflected by the finger; using an image sensor to receive a reflected first light and capture a bright area image; using a control and processing unit to calculate a light-receiving pixel number (B) based on the bright area image, and compare with a number of light-receivable pixels (A) of the image sensor to obtain a ratio (B/A) % of the number of light-receiving pixels of the bright area image and the number of light-receivable pixels of the image sensor to determine whether a pressure exerted by of the finger is sufficient; activating at least one second light source to project a second light toward the substrate when the pressure exerted by the finger is determined to be sufficient, the second light penetrating the substrate and the skin of the finger and then being reflected by a blood vessel; using the image sensor to receive a reflected second light and capture a blood vessel volume change image; and using the control and processing unit to calculate a systolic pressure or a diastolic pressure based on the blood vessel volume change image.

7 . The blood pressure measurement method according to claim 6 , wherein when the ratio is between 90 and 98%, the control and processing unit determines that the pressure exerted by the finger is sufficient; when the ratio is less than 90%, the control and processing unit determines that the pressure exerted by the finger is insufficient; and when the ratio is greater than 98%, the control and processing unit determines that the pressure exerted by the finger is too high.

8 . The blood pressure measurement method according to claim 6 , wherein a reflective layer is disposed between the protrusion portion and the substrate to prevent a path of the total reflection of the first light from changing or being destroyed before the first light enters the hollow portions.

9 . The blood pressure measurement method according to claim 6 , wherein when the control and processing unit determines that the pressure exerted by the finger is insufficient or too high, a warning unit sends out a warning signal.

10 . The blood pressure measurement method according to claim 6 , wherein a uniform sheet light source projects a third light toward the substrate and the third light passes through the hollow portions and the substrate in sequence, the image sensor receives the third light and captures an actual bright area image; and the control and processing unit determines an actual number of light-receivable pixels of the image sensor according to the actual bright area image.

Assignees

• Guangzhou Tyrafos Semiconductor Tech Co Ltd

Inventors

• Chung Jun-Wen
• Fu Hsu-Wen
• Fu Za-Hara
• Chang Chia-Hao

Classifications

• A61B5/6826 Primary

  Finger · CPC title

• A61B5/02416

  using photoplethysmograph signals, e.g. generated by infrared radiation (A61B5/14552 takes precedence) · CPC title

• A61B5/021 Primary

  Measuring pressure in heart or blood vessels · CPC title

• A61B5/02108 Primary

  from analysis of pulse wave characteristics · CPC title