Living body information measuring apparatus, living body information measuring method, body fat measuring apparatus, body fat measuring method, and program recording medium

• US 20040039287A1
• Filed: 04/14/2003
• Published: 02/26/2004
• Est. Priority Date: 12/24/1998
• Status: Active Grant

• Current Assignee: Panasonic Electric Works Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Motomi Horiuchi, Shinji Uchida
• Inventors: Horiuchi, Motomi, Uchida, Shinji
• Granted Patent: US 6,985,767 B2
• Time in Patent Office: Days
• US Class Current: 600/476
• 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 5/1075 for measuring dimensions by non-invasive methods, e.g. for determining thickness of tissue layer A61B8/0858 takes precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/4872 Body fat

Abstract

A body fat measuring apparatus is provided with a light emitting device 1 for projecting light rays to a subject'"'"'s tissue, light receiving devices 3 and 4 for detecting a transmitted light ray having passed through the subject'"'"'s tissue and/or a reflected light ray reflected inside the subject'"'"'s body, and a CPU 6 for calculating the subject'"'"'s subcutaneous fat thickness and/or body fat percentage by performing an operation by use of the detection results of the light receiving devices 3 and 4. The light receiving devices 3 and 4 are situated at different distances from the light emitting device 1.

Claims

1. A living body information measuring method wherein a plurality of paths from a light emitting portion to a light receiving portion are created, and based on a light reception signal, from a path with higher accuracy, of a plurality of light reception signals obtained from the paths, living body information is calculated by a signal processor.

2. A living body information measuring method according to claim 1,

wherein a reference value is prepared, and the path with higher accuracy is decided by use of the reference value.

3. A living body information measuring method according to claim 1,

wherein the path with higher accuracy is decided by comparing the plurality of light reception signals obtained from the plurality of paths with one another.

4. A living body information measuring method according to claim 1,

wherein light rays are simultaneously or successively emitted from the light emitting portion.

5. A living body information measuring method according to claim 1,

wherein the signal processor also analyzes a wavelength component of light as well to process the light reception signals.

37. A program recording medium being readable by a computer and recording therein a program and/or data for causing a computer to perform all or some of operations of all or some of steps of a living body information measuring method according to claim 1.

42. A program recording medium being readable by a computer and recording therein a program and/or data for causing a computer to perform all or some of operations of all or some of steps of a body fat measuring method according to claim 1.

6. A living body information measuring apparatus comprising:

a light emitting portion for projecting light rays to a subject;

a light receiving portion for detecting, of the light rays, a transmitted light ray or a reflected light ray having passed through the subject; and

a signal processor for calculating the subject'"'"'s living body information by analyzing a light ray detected by the light receiving portion,

wherein at least one of the number of light emitting portions and the number of light receiving portions is not less than two, and

wherein the signal processor analyzes, of a plurality of light rays detected by the light receiving portion, a light ray with higher accuracy to calculate the subject'"'"'s living body information.

7. A living body information measuring apparatus according to claim 6,

wherein the signal processor has a function of analyzing each wavelength component of the light ray detected by each light receiving portion to determine whether the light ray has passed through a blood vessel of the subject'"'"'s or not.

8. A living body information measuring apparatus according to claim 6, further comprising a display for displaying the measured living body information.

35. A program recording medium being readable by computer and recording therein a program and/or data for causing a computer to perform all or some of functions of all or some of elements of a living body information measuring apparatus according to claim 6.

40. A program recording medium being readable by a computer and recording therein a program and/or data for causing a computer to perform all or some of functions of all or some of elements of a body fat measuring apparatus according to claim 6.

9. A body fat measuring apparatus comprising:

a light emitting portion for projecting light rays to a subject'"'"'s tissue;

a light receiving portion for detecting, of the light rays, a transmitted light ray having passed through the subject'"'"'s tissue and/or a reflected light ray reflected inside the subject'"'"'s body; and

signal processing operation means for calculating the subject'"'"'s subcutaneous fat thickness and/or body fat percentage by performing an operation by use of a detection result of the light receiving portion,

wherein either the number of light emitting portions or the number of light receiving portions is not less than two, and wherein the not less than two light emitting portions or light receiving portions are situated at different distances from corresponding light receiving portions or light emitting portions.

10. A body fat measuring apparatus according to claim 9,

wherein the light receiving portion comprises:

a first light receiving portion situated at a predetermined distance from the light emitting portion; and

a second light receiving portion situated farther away from the light emitting portion than the first light receiving portion,

wherein the first light receiving portion detects the transmitted light ray and/or the reflected light ray having arrived by way of the subject'"'"'s skin or skin and a layer in the vicinity thereof,

wherein the second light receiving portion detects the transmitted light ray and/or the reflected light ray having arrived by way of the subject'"'"'s skin and subcutaneous fat layer, and

wherein the signal processing operation means corrects a detection result of the second light receiving portion by a detection result of the first light receiving portion and performs an operation by use of a result of the correction to thereby calculate the subject'"'"'s subcutaneous fat thickness or body fat percentage.

11. A body fat measuring apparatus according to claim 10,

wherein the correction performed by the signal processing operation means is to divide the detection result of the second light receiving portion by the detection result of the first light receiving portion.

12. A body fat measuring apparatus according to claim 9,

wherein the signal processing operation means analyzes a light component of a wavelength of substantially 950 nm, and

wherein the distance between the first light receiving portion and the second light receiving portion exceeds 2 mm.

13. A body fat measuring apparatus according to claim 9,

wherein the signal processing operation means analyzes all or some of light components of wavelengths of substantially 600 to 660 nm, and

wherein the distance between the first light receiving portion and the second light receiving portion is not less than 2 mm.

14. A body fat measuring apparatus according to claim 13,

wherein a central wavelength of the light projected from the light emitting portion is 650 nm.

15. A body fat measuring apparatus according to claim 9,

wherein the light emitting portion comprises:

a first light emitting portion situated at a predetermined distance from the light receiving portion; and

a second light emitting portion situated farther away from the light receiving portion than the first light emitting portion,

wherein the light receiving portion detects a light ray projected from the first light emitting portion as a first transmitted light ray and/or reflected light ray having passed through the subject'"'"'s skin or skin and a layer in the vicinity thereof, and detects a light ray projected from the second light emitting portion as a second transmitted light ray and/or reflected light ray having passed through the subject'"'"'s skin and subcutaneous fat layer and/or a reflected light ray, and

wherein the signal processing operation means corrects a detection result obtained by the second light emitting portion and the light receiving portion by a detection result obtained by the first light emitting portion and the light receiving portion and performs an operation by use of a result of the correction to thereby calculate the subject'"'"'s subcutaneous fat thickness or body fat percentage.

16. A body fat measuring apparatus according to claim 11,

wherein the correction performed by the signal processing operation means is to divide the detection result obtained by the second light emitting portion and the light receiving portion by the detection result obtained by the first light emitting portion and the light emitting portion.

17. A body fat measuring apparatus according to claim 15,

wherein the signal processing operation means analyzes a light component of a wavelength of substantially 950 nm, and

wherein the distance between the first light emitting receiving portion and the second light emitting portion exceeds 2 mm.

18. A body fat measuring apparatus according to claim 16,

wherein the signal processing operation means analyzes a light component of a wavelength of substantially 950 nm, and

wherein the distance between the first light emitting receiving portion and the second light emitting portion exceeds 2 mm.

19. A body fat measuring apparatus according to claim 15,

wherein the signal processing operation means analyzes all or some of light components of wavelengths of substantially 600 to 660 nm, and

wherein the distance between the first light emitting portion and the second light emitting portion is not less than 2 mm.

20. A body fat measuring apparatus according to claim 16,

wherein the signal processing operation means analyzes all or some of light components of wavelengths of substantially 600 to 660 nm, and

wherein the distance between the first light emitting portion and the second light emitting portion is not less than 2 mm.

21. A body fat measuring apparatus according to claim 15,

wherein a central wavelength of the light projected by the first and the second light emitting portions is substantially 650 nm.

22. A body fat measuring method using a body fat measuring apparatus according to claim 10, said body fat measuring method comprising the steps of:

projecting light rays to the subject by the light emitting portion;

detecting a transmitted light ray and/or a reflected light ray having arrived by way of the subject'"'"'s skin or skin and a layer in the vicinity thereof by the first light receiving portion;

detecting a transmitted light ray and/or a reflected light ray having arrived by way of the subject'"'"'s skin and subcutaneous fat layer and/or by the second light receiving portion; and

calculating the subject'"'"'s subcutaneous fat thickness or body fat percentage by the signal processing operation means by correcting a detection result of the second light receiving portion by a detection result of the first light receiving portion and performing an operation by use of a result of the correction.

23. A body fat measuring method using a body fat measuring apparatus according to claim 15, said body fat measuring method comprising:

a step in which a light ray projected by the first light emitting portion is detected by the light receiving portion as a first transmitted light ray and/or a reflected light way having passed through the subject'"'"'s skin or skin and a layer in the vicinity thereof;

a step in which a light ray projected by the second light emitting portion is detected by the light receiving portion as a second transmitted light ray and/or a reflected light ray having passed through the subject'"'"'s skin and subcutaneous fat layer; and

a step in which the subject'"'"'s subcutaneous fat thickness or body fat percentage is calculated by the signal processing operation means by correcting a detection result obtained by the second light emitting portion and the light receiving portion by a detection result obtained by the first light emitting portion and the light receiving portion and performing an operation by use of a result of the correction.

24. A body fat measuring method using a body fat measuring apparatus according to any of claims 16, said body fat measuring method comprising:

a step in which a light ray projected by the first light emitting portion is detected by the light receiving portion as a first transmitted light ray and/or a reflected light way having passed through the subject'"'"'s skin or skin and a layer in the vicinity thereof;

a step in which a light ray projected by the second light emitting portion is detected by the light receiving portion as a second transmitted light ray and/or a reflected light ray having passed through the subject'"'"'s skin and subcutaneous fat layer; and

a step in which the subject'"'"'s subcutaneous fat thickness or body fat percentage is calculated by the signal processing operation means by correcting a detection result obtained by the second light emitting portion and the light receiving portion by a detection result obtained by the first light emitting portion and the light receiving portion and performing an operation by use of a result of the correction.

25. A living body information measuring apparatus comprising:

a light emitting portion for projecting light rays to a subject'"'"'s tissue;

a light receiving portion for detecting, of the light rays, a transmitted light ray having passed through the subject'"'"'s tissue and/or a reflected light ray reflected inside the subject'"'"'s body; and

signal processing operation means for calculating the subject'"'"'s living body information by performing an operation by use of a detection result of the light receiving portion,

wherein either the number of light emitting portions or the number of light receiving portions is not less than two,

wherein the not less than two light emitting portions or light receiving portions are situated at different distances from corresponding light receiving portion or light emitting portions,

wherein light sources of the plurality of light emitting portions are the same, or photoelectric conversion devices of the plurality of light receiving portions are the same, and

wherein one of outputs of the plurality of light emitting portions or outputs of the plurality of light receiving portions is corrected by another one of the outputs.

26. A living body information measuring apparatus according to claim 25,

wherein the plurality of light emitting portions are realized by the light source being moved by moving means, or the plurality of light receiving portions are realized by the photoelectric conversion device being moved by the moving means.

27. A living body information measuring apparatus according to claim 25,

wherein a plurality of optical paths are provided from the one light source and the plurality of light emitting portions are realized by switch among the optical paths, or a plurality of optical paths are provided from the one photoelectric conversion device and the plurality of light receiving portions are realized by switching among the optical paths.

28. A living body information measuring apparatus according to claim 27,

wherein the switching among the optical paths is performed by optical path adjusting means comprising a movable shutter disposed in front of the light source and having a hole and a plurality of optical path members derived from the shutter.

29. A living body information measuring apparatus according to claim 27,

wherein the optical paths are made of an optical fiber or an acrylic resin.

30. A living body information measuring apparatus according to claim 25,

wherein attenuating means is provided for attenuating a quantity of light output from, of the plurality of light emitting portions, a light emitting portion closer to the light receiving portion.

31. A living body information measuring apparatus according to claim 30,

wherein the attenuating means has a function of attenuating the quantity of the light to 50 to 5%.

32. A living body information measuring apparatus according to claim 30,

wherein the attenuating means is made of a transparent resin substrate and an absorbing member attached thereonto.

36. A program recording medium being readable by computer and recording therein a program and/or data for causing a computer to perform all or some of functions of all or some of elements of a living body information measuring apparatus according to claim 25.

41. A program recording medium being readable by a computer and recording therein a program and/or data for causing a computer to perform all or some of functions of all or some of elements of a body fat measuring apparatus according to claim 25.

33. A method of measuring living body information by projecting light from a light emitting portion to a subject and measuring a quantity of light having passed through the subject, said method comprising:

a first step in which the light emitting portion is situated adjacent to a light receiving portion, and the quantity of the light having passed through the subject is measured by the light receiving portion;

a second step in which a distance between the light receiving portion and the light emitting portion is increased, light is projected to the subject, and the quantity of the light having passed through the subject is measured by the light receiving portion; and

a third step in which a quotient (division) of a measurement value obtained by the first step and a measurement value obtained by the second step is obtained to calculate living body information.

38. A program recording medium being readable by a computer and recording therein a program and/or data for causing a computer to perform all or some of operations of all or some of steps of a living body information measuring method according to claim 33.

43. A program recording medium being readable by a computer and recording therein a program and/or data for causing a computer to perform all or some of operations of all or some of steps of a body fat measuring method according to claim 33.

34. A method of measuring living body information by projecting light emitted from a light emitting portion to a subject and measuring a quantity of light having passed through the subject, said method comprising:

a first step in which the light emitted from the light emitting portion is made incident on the subject through a first light directing path, and the quantity of the light having passed through the subject is measured by a light receiving portion disposed adjacent to an exit end of the first light directing path;

a second step in which the light emitted from the light emitting portion is made incident on the subject through a second light directing path disposed so that an exit end thereof is situated farther away from the light receiving portion than the exit end of the first light directing path, and the quantity of the light having passed through the subject is measured; and

a third step in which a quotient (division) of a measurement value obtained by the first step and a measurement value obtained by the second step is obtained to calculate living body information.

39. A program recording medium being readable by a computer and recording therein a program and/or data for causing a computer to perform all or some of operations of all or some of steps of a living body information measuring method according to claim 34.

44. A program recording medium being readable by a computer and recording therein a program and/or data for causing a computer to perform all or some of operations of all or some of steps of a body fat measuring method according to claim 34.