Organism state measuring device and relaxation instructing device

• US 6,081,742 A
• Filed: 08/04/1998
• Issued: 06/27/2000
• Est. Priority Date: 09/10/1996
• Status: Expired due to Term

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Amano, Kazuhiko, Ishiyama, Hitoshi, Uebaba, Kazuo
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): LAYNO, CARL HERNANDZ
• Application Number:
  US09/068,755
• Time in Patent Office: 693 Days
• Field of Search: 600/483, 600/484, 600/513
• US Class Current: 600/513
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/022 by applying pressure to close blood vessels, e.g. against the skin; Ophthalmodynamometers
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/721 using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured
• CPC Class Codes: A61B 5/7232 involving compression of the physiological signal, e.g. to extend the signal recording period
• CPC Class Codes: A61B 5/7239 using differentiation including higher order derivatives
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 5/726 using Wavelet transforms

Abstract

Devices are known for measuring a subject'"'"'s respiratory rate based on the subject'"'"'s pulse wave or level of electrocardiogram. When the subject is exercising or carrying out daily activities, however, an electromyogram becomes imposed on the cardiogram waveform, so that a body motion component is superimposed on the pulse wave. This leads to an incorrect measured result. To overcome this drawback, a portable portion in the form of a wristwatch worn by the subject and a personal computer comprising device main body 330 are provided. A photoelectric pulse wave sensor is attached to the base of the subject'"'"'s finger, and the pulse waveform is measured. An acceleration sensor is provided to the portable portion, and employed to detect the subject'"'"'s body motion spectrum. Device main body 330 performs a window function on the pulse wave, and removes the acceleration component, so that the body motion spectrum is removed from the frequency spectrum of the pulse wave. Using the obtained result, the respiratory rate and change rate of the respiratory rate are generated.

Claims

1. A physiological state measuring device comprising:

circulatory system information detecting means for detecting a subject'"'"'s circulatory system information;

means for detecting a pulse rate based on the detected circulatory system information;

means for performing frequency analysis of the detected circulatory system information and for obtaining frequency components;

determining means for determining a frequency range on the basis of the detected pulse rate;

limiting means for limiting the obtained frequency components to the frequency range;

measuring means for measuring a respiratory rate of the subject on the basis of the limited frequency components.

2. A physiological state measuring device according to claim 1, wherein the circulatory system information comprises an amount of change in the cycle of a pulse wave or a level of an electrocardiogram.

3. A physiological state measuring device according to claim 1, wherein the circulatory system information comprises an amount of change in an amplitude value of a pulse wave or a level of an electrocardiogram.

4. A physiological state measuring device according to claim 1, further comprising:

a portable portion which is worn by the subject for detecting the circulatory system information; and

a main portion to communicate with the portable portion.

5. A physiological state measuring means according to claim 1, further comprising warning means for providing a warning which relies on one of the subject'"'"'s five senses, when the measured respiratory rate is outside a specific range.

6. A physiological state measuring device according to claim 1, further comprising communicating means for sending and receiving information including indicators of physiological state to and from an external device which is provided separately from the main body of the device.

7. A physiological state measuring device according to claim 6, wherein the communicating means comprises a recognition information recording means in which particular recognition numbers are provided, wherein a recognition number is associated with communicated information and sent between the external device and the device main body.

8. A physiological state measuring device according to claim 7, wherein data transmission between the device main body and the external device is carried out using compressed data.

9. A physiological state measuring device according to claim 1, further comprising calculating means for calculating the change rate of the respiratory rate based on the measured respiratory rate.

10. The physiological state measuring device, according to claim 9, is used in a relaxation guidance device comprising:

indicator generating means for generating indicators showing the subject'"'"'s degree of relaxation based on the change rate of the respiratory rate calculated by the calculating means; and

notifying means for notifying the subject of the indicator.

11. The physiological state measuring device according to claim 10, wherein the indicator generating means generates an indicator showing the subject'"'"'s degree of relaxation based on a comparison between a threshold value and the change rate of the respiratory rate.

12. The physiological state measuring device according to claim 11, wherein the indicator generating means comprises:

pulse rate calculating means for determining pulse rate based on circulatory system information;

rate-of-change-in-pulse-rate calculating means for calculating the rate of change in the pulse rate; and

threshold value table for storing in advance threshold values which have been associated with rates of change in the pulse rate;

wherein, the indicator generating means references the rate of change in the pulse rate calculated by the rate-of-change-in-pulse-rate calculating means, reads out the threshold values from the threshold value table, and generates indicators showing the subject'"'"'s degree of relaxation based on the threshold value.

13. The physiological state measuring device according to claim 10, further comprising communicating means for sending the change rate of the respiratory rate calculated by the calculating means, and receives the indicator generated by the indicator generating means which is provided to the external device, to and from the external device which is provided external to the main body of the device;

wherein, the subject is notified of the indicator by the notifying means provided to the device main body.

14. A physiological state measuring device comprising:

circulatory system information detecting means for detecting information about a subject'"'"'s circulatory system;

means for detecting a pulse rate based on the detected circulatory system information;

means for performing frequency spectral analysis of the detected circulatory system information;

extracting means for extracting a region determined according to the pulse rate from among the frequency spectrums for the analyzed circulatory system information; and

measuring means for measuring the subject'"'"'s respiratory rate based on the frequency spectrum in the extracted region.

15. A physiological state measuring device according to claim 14, further comprising body motion removing means for removing a body motion spectrum corresponding to the subject'"'"'s body motion from the frequency spectrum extracted by the extracting means;

wherein, the subject'"'"'s respiratory rate is generated based on an output from the body motion removing means.

16. A physiological state measuring device according to claim 15, wherein the body motion removing means comprises:

body motion detecting means for detecting the subject'"'"'s body motion;

body motion spectrum detecting means for determining the body motion spectrum corresponding to the subject'"'"'s body motion, based on results detected by the body motion detecting means; and

body motion correcting means for removing the body motion spectrum from the frequency spectrum extracted by the extracting means.

17. A physiological state measuring device according to claim 15, wherein the body motion removing means comprises:

a fundamental frequency table comprising predetermined associations for the respiratory fundamental frequency and the body motion fundamental frequency according to a change in exercise intensity; and

a frequency specifying member for referencing the fundamental frequency table and specifying the respiratory fundamental frequency and the body motion fundamental frequency from among the frequency spectrums extracted by the extracting means;

wherein, the respiratory rate is calculated based on the respiratory fundamental frequency specified by the frequency specifying member.

18. A physiological state measuring means according to claim 16, wherein the body motion detecting means detects acceleration of the subject'"'"'s arms, and the body motion correcting means removes the body motion spectrum corresponding to the acceleration frequency from the frequency spectrum.