BIOLOGICAL-INFORMATION OBTAINING APPARATUS AND METHOD THEREOF

• US 20080306372A1
• Filed: 06/02/2008
• Published: 12/11/2008
• Est. Priority Date: 06/06/2007
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Masuno, Tomonori, Ohki, Mitsuharu
• Granted Patent: US 8,180,437 B2
• Time in Patent Office: Days
• US Class Current: 600/407
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: A61B 5/02125 of pulse wave propagation time
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/6826 Finger
• CPC Class Codes: A61B 5/6838 Clamps or clips

Abstract

A biological-information obtaining apparatus includes a light-emitting unit, an image sensor configured to capture images, in time sequence, relating to a living body, a lens, an extreme-occurrence-time obtaining unit configured to obtain times T1 and T2 at which extremes occur in time sequence with respect to brightness values of a first region and a second region of each of the captured images, the time T1 being obtained for one of the first regions and the time T2 being obtained for one of the second regions, and a PWV calculation unit configured to calculate a pulse wave velocity P=(Y×L/f)/(T2−T1), where Y represents a distance on the image sensor, the distance corresponding to a distance between the first region and the second region, f represents the focal length of the lens, and L represents a distance between the lens and the living body.

Claims

1. A biological-information obtaining apparatus comprising:

light-emitting means for emitting light;

an image sensor for capturing images, in time sequence, obtained by irradiating a living body with the light emitted and by causing the light to be transmitted through or reflected by the living body;

a lens for causing the images to be formed on the image sensor;

extreme-occurrence-time obtaining means for obtaining times T1 and T2 at which extremes occur in time sequence with respect to brightness values of a first region and a second region of each of the captured images, the time T1 being obtained for one of the first regions and the time T2 being obtained for one of the second regions; and

pulse-wave-velocity calculation means for calculating a pulse wave velocity P=(Y×

L/f)/(T2−

T1), where Y represents a distance on the image sensor, the distance corresponding to a distance between the first region and the second region, f represents the focal length of the lens, and L represents a distance between the lens and the living body in the case of capturing the images.

2. The biological-information obtaining apparatus according to claim 1, wherein the light-emitting means emits monochromatic light.

3. The biological-information obtaining apparatus according to claim 1, wherein the extreme-occurrence-time obtaining means obtains the times T1 and T2 at which the extremes occur in time sequence with respect to brightness averages of the first region and the second region of each of the captured images, the time T1 being obtained for one of the first regions and the time T2 being obtained for one of the second regions.

4. The biological-information obtaining apparatus according to claim 1, wherein

the extreme-occurrence-time obtaining means obtains the times T1 and T2 at which the extremes occur in time sequence with respect to brightness averages of the first region and the second region of each of the captured images, the first region and the second region being obtained by halving the captured image, the time T1 being obtained for one of the first regions and the time T2 being obtained for one of the second regions, and

the pulse-wave-velocity calculation means calculates the pulse wave velocity P=(Y×

L/f)/(T2−

T1), where Y represents a distance on the image sensor, the distance corresponding to a distance between midpoints of the first and second regions.

5. A biological-information obtaining apparatus comprising:

light-emitting means for emitting light;

an image sensor for capturing images, in time sequence, obtained by irradiating a living body with the light emitted and by causing the light to be transmitted through or reflected by the living body;

a lens for causing the images to be formed on the image sensor;

parameter storing means for storing, as parameters, a length K of the image sensor, the focal length f of the lens, and a distance L between the lens and the living body in the case of capturing the images;

extreme-occurrence-time obtaining means for obtaining times T1 and T2 at which extremes occur in time sequence with respect to brightness averages of a first region and a second region of each of the captured images, the first region and the second region being obtained by halving the captured image, the time T1 being obtained for one of the first regions and the time T2 being obtained for one of the second regions; and

pulse-wave-velocity calculation means for calculating a pulse wave velocity P=((K/2)×

L/f)/(T2−

T1) on the basis of the times T1 and T2 obtained by the extreme-occurrence-time obtaining means and the parameters stored in the parameter storing means.

6. A method of obtaining biological information, the method being performed by a biological-information obtaining apparatus including light-emitting means for emitting light, an image sensor for capturing images, in time sequence, obtained by irradiating a living body with the light emitted and by causing the light to be transmitted through or reflected at the living body, a lens for causing the images to be formed on the image sensor, and parameter storing means for storing, as parameters, a length K of the image sensor, the focal length f of the lens, and a distance L between the lens and the living body in the case of capturing the images, the method comprising the steps of:

obtaining times T1 and T2 at which extremes occur in time sequence with respect to brightness averages of a first region and a second region of each of the captured images, the first region and the second region being obtained by halving the captured image, the time T1 being obtained for one of the first regions and the time T2 being obtained for one of the second regions; and

calculating a pulse wave velocity P=((K/2)×

L/f)/(T2−

T1) on the basis of the times T1 and T2 obtained by the extreme-occurrence-time obtaining means and the parameters stored in the parameter storing means.

7. A biological-information obtaining apparatus comprising:

a light-emitting unit configured to emit light;

an image sensor configured to capture images, in time sequence, obtained by irradiating a living body with the light emitted and by causing the light to be transmitted through or reflected at the living body;

a lens configured to cause the images to be formed on the image sensor;

an extreme-occurrence-time obtaining unit configured to obtain times T1 and T2 at which extremes occur in time sequence with respect to brightness values of a first region and a second region of each of the captured images, the time T1 being obtained for one of the first regions and the time T2 being obtained for one of the second regions; and

a pulse-wave-velocity calculation unit configured to calculate a pulse wave velocity P=(Y×

L/f)/(T2−

T1), where Y represents a distance on the image sensor, the distance corresponding to a distance between the first region and the second region, f represents the focal length of the lens, and L represents a distance between the lens and the living body in the case of capturing the images.

8. A biological-information obtaining apparatus comprising:

a light-emitting unit configured to emit light;

an image sensor configured to capture images, in time sequence, obtained by irradiating a living body with the light emitted and by causing the light to be transmitted through or reflected at the living body;

a lens configured to cause the images to be formed on the image sensor;

a parameter storage unit configured to store, as parameters, a length K of the image sensor, the focal length f of the lens, and a distance L between the lens and the living body in the case of capturing the images;

an extreme-occurrence-time obtaining unit configured to obtain times T1 and T2 at which extremes occur in time sequence with respect to brightness averages of a first region and a second region of each of the captured images, the first region and the second region being obtained by halving the captured image, the time T1 being obtained for one of the first regions and the time T2 being obtained for one of the second regions; and

a pulse-wave-velocity calculation unit configure to calculate a pulse wave velocity P=((K/2)×

L/f)/(T2−

T1) on the basis of the times T1 and T2 obtained by the extreme-occurrence-time obtaining unit and the parameters stored in the parameter storage unit.