Non-contact blood-pressure measuring device and non-contact blood-pressure measuring method

Patent metadata

Field	Value
Publication number	US-2016100766-A1
Application number	US-201514873229-A
Country	US
Kind code	A1
Filing date	Oct 2, 2015
Priority date	Oct 9, 2014
Publication date	Apr 14, 2016
Grant date	—

Abstract

A non-contact blood-pressure measuring device includes: an image acquiring section that acquires a skin image obtained by capturing skin of a user; a pulse-wave timing calculating section that calculates, as a pulse-wave timing, time information indicative of a time at which time-varying luminance in the skin image reaches a peak; a millimeter-wave acquiring section that acquires a signal of a radio wave reflected by the user; a heartbeat timing calculating section that calculates, as a heartbeat timing, time information indicative of a time at which a time-varying distance to the user obtained on the basis of the signal of the radio wave acquired by the millimeter-wave acquiring section reaches a peak; and a blood-pressure determining section that determines blood pressure of the user on the basis of a time difference between the pulse-wave timing and the heartbeat timing.

First claim

What is claimed is:

1 . A non contact blood-pressure measuring device comprising:
an image acquirer that acquires a skin image obtained by capturing skin of a user; a pulse-wave timing calculator that calculates a temporal change of luminance in the skin image by using the skin image and calculates, as a pulse-wave timing, time information indicative of a time at which the luminance reaches a peak; a radio wave acquirer that acquires a signal of a radio wave reflected by the user and received by a reception antenna; a heartbeat timing calculator that calculates a temporal change of a distance between the user and the reception antenna by using the signal of the radio wave acquired by the radio wave acquirer and calculates, as a heartbeat timing, time information indicative of a time at which the distance reaches a peak; and a blood-pressure determiner that determines blood pressure of the user on the basis of a time difference between the pulse-wave timing and the heartbeat timing.

2 . The non-contact blood-pressure measuring device according to claim 1 , wherein
the heartbeat timing calculator calculates, as the heartbeat timing, the time information indicative of a time at which the distance reaches a peak within a predetermined time range before the pulse-wave timing calculated by the pulse-wave timing calculator.

3 . The non-contact blood-pressure measuring device according to claim 1 , further comprising a posture measurer that measures an amount of change of a posture of the user on the basis of the skin image acquired by the image acquirer, wherein
the blood-pressure determiner determining the blood pressure on the basis of a time difference between the pulse-wave timing calculated on the basis of the skin image acquired by the image acquirer during a period in which the amount of change measured by the posture measurer is equal to or lower than a predetermined threshold value and the heartbeat timing calculated on the basis of the radio wave acquired by the radio wave acquirer during the period.

4 . The non-contact blood-pressure measuring device according to claim 3 , wherein
the image acquirer acquires the skin image obtained by capturing a portion including the skin of the user and a chest of the user; the posture measurer measures, as the amount of change, an amount of movement of a skin portion of the skin image or an amount of movement of a chest portion of the skin image; and the blood-pressure determiner that determines the blood pressure on the basis of a time difference between the pulse-wave timing calculated on the basis of the skin image acquired by the image acquirer during a period in which the amount of movement of the skin portion or the chest portion measured by the posture measurer is equal to or lower than a predetermined threshold value and the heartbeat timing calculated on the basis of the radio wave acquired by the radio wave acquirer during the period.

5 . The non-contact blood-pressure measuring device according to claim 3 , wherein
the image acquirer includes an acquirer for posture measurement that acquires an image obtained by capturing the user from a direction different from a direction in which the radio wave acquirer acquires a radio wave; and the posture measurer measures the amount of change on the basis of the image acquired by the acquirer for posture measurement.

6 . The non-contact blood-pressure measuring device according to claim 1 , wherein
the blood-pressure determiner determines the blood pressure on the basis the time difference between the pulse-wave timing calculated by the pulse-wave timing calculator and the heartbeat timing calculated by the heartbeat timing calculator by using a predetermined relational expression including a predetermined parameter and the time difference.

7 . The non-contact blood-pressure measuring device according to claim 6 , wherein
the non-contact blood-pressure measuring device further includes a cuff-type blood pressure measurer that measures the blood pressure of the user by using a cuff; and the blood-pressure determiner determines the predetermined parameter included in the relational expression by using the blood pressure of the user measured by the cuff-type blood pressure measurer.

8 . The non-contact blood-pressure measuring device according to claim 7 , wherein
the pulse-wave timing calculator calculates a plurality of pulse-wave timings; the heartbeat timing calculator calculates a plurality of heartbeat timings that correspond to the respective calculated pulse-wave timings; and the blood-pressure determiner determines the predetermined parameter included in the relational expression on the basis of (i) a time difference determined on the basis of a pair of pulse-wave timing and heartbeat timing included in a period from a first timing at which maximum blood pressure is measured by the cuff-type blood pressure measurer to a second timing at which minimum blood pressure is measured by the cuff-type blood pressure measurer, (ii) a time difference determined on the basis of a pair of pulse-wave timing and heartbeat timing that is closest to the first timing, or (iii) a time difference determined on the basis of a pair of pulse-wave timing and heartbeat timing that is closest to the second timing, among pairs of pulse-wave timing and heartbeat timing that correspond to each other.

9 . The non-contact blood-pressure measuring device according to claim 7 , wherein
the skin image is a skin image obtained by capturing skin of a portion anterior to a portion at which the cuff-type blood pressure measurer is attached among portions of an arm of the user.

10 . The non-contact blood-pressure measuring device according to claim 1 , wherein
the pulse-wave timing calculator calculates a plurality of pulse-wave timings; the heartbeat timing calculator calculates a plurality of heartbeat timings that correspond to the respective calculated pulse-wave timings; and the blood-pressure determiner calculates a plurality of time differences on the basis of respective pairs of pulse-wave timing and heartbeat timing that correspond to each other and determines the blood pressure on the basis of a value obtained by performing statistical processing on the calculated plurality of time differences.

11 . The non-contact blood-pressure measuring device according to claim 6 , further comprising:
a model accumulator in which candidates of the predetermined parameter included in the relational expression are stored; and an acceptor that accepts profile information including at least one of height, weight, age, and blood pressure of the user, the blood-pressure determiner determining a candidate to be used to determine the blood pressure among the candidates stored in the model accumulator on the basis of the profile information accepted by the acceptor and determines the blood pressure by using the relational expression including the determined candidate.

12 . The non-contact blood-pressure measuring device according to claim 1 , further comprising a second presenter that presents information designating a position of a body of the user so that the body of the user is located at a position suitable for acquisition of the skin image by the image acquirer and for acquisition of the radio wave by the radio wave acquirer.

13 . The non-contact blood-pressure measuring device according to claim 12 , wherein
the second presenter further presents, to the user, instruction information instructing the user to stay still, to be at rest, to inhale, or to exhale when the image acquirer acquires the skin image and when the radio wave acquirers acquires t

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Yoshioka Mototaka
• Ozawa Jun

Classifications

• A61B5/0205 Primary

  Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition · CPC title

• A61B5/02108

  from analysis of pulse wave characteristics · CPC title

• A61B5/7278

  Artificial waveform generation or derivation, e.g. synthesizing signals from measured signals · CPC title

• A61B5/0507

  using microwaves or terahertz waves · CPC title

• G01S13/88

  Radar or analogous systems specially adapted for specific applications (electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00) · CPC title