Heart rate monitor and heart rate measuring method

• US 20030018274A1
• Filed: 07/01/2002
• Published: 01/23/2003
• Est. Priority Date: 07/19/2001
• Status: Active Grant

• Current Assignee: Nihon Seimitsu Sokki Company Limited
• Original Assignee: Nihon Seimitsu Sokki Company Limited
• Inventors: Takahashi, Yoshikazu, Koshino, Shinji, Mitsuhashi, Shintaro, Baker, Wayne, Shiogai, Hajime
• Granted Patent: US 6,783,501 B2
• Time in Patent Office: Days
• US Class Current: 600/500
• 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 5/6814 Head
• CPC Class Codes: A61B 5/6816 Ear lobe

Abstract

Accurate occurrences of pulsation per unit time, that is, a heart rate is measured with a burden on a subject person being reduced to be very small and without being susceptible to body vibrations accompanying exercise. A heart rate monitor is produced, in which a light-emitting element 11 and a light-receiving element 12 are fitted to a head of a human body, light from the light-emitting element 11 is reflected at or transmitted through a subcutaneous artery 4 and/or blood running in the subcutaneous artery, the reflected or transmitted light is detected at the light-receiving element 12, and by using a CPU 14, the pulsation of the subcutaneous artery 4 and/or a change in bloodstream running in the subcutaneous artery 4 is measured from a change in intensity of the light detected at the light-receiving element 12, a pulse rate of the change in the bloodstream per unit time is calculated from this measured value, and the calculated pulse rate of the change in the bloodstream per unit time is regarded as a heart rate.

Claims

1. A heart rate monitor comprising a light-emitting element, a light-receiving element, and a CPU,

light from said light-emitting element being reflected at or transmitted through blood running in a blood vessel,

said light-receiving element detecting the reflected or transmitted light,

said CPU measuring a change in bloodstream running in the blood vessel from a change in intensity of the light detected at said light-receiving element, and

said CPU calculating a pulse rate of the change in the bloodstream per unit time from the measured value, and regarding the calculated pulse rate of the change in the bloodstream per unit time as a heart rate,

wherein said light-emitting element and said light-receiving element are fitted to a human head having a space of 4 mm to 10 mm between them, and

wherein light with a wavelength of 900 nm to 1200 nm emitted by said light-emitting element is reflected at or transmitted through a subcutaneous artery and/or blood running in the subcutaneous artery and is detected at said light-receiving element.

2. The heart rate monitor according to claim 1, further comprising:

a display unit for displaying the calculated heart rate,

wherein said display unit transmits the calculated heart rate to a measuring person and/or a subject person by means of an optical display, a voice, radio, and/or bone conduction.

3. The heart rate monitor according to claim 1 or claim 2, further comprising:

a storage device for storing the calculated heart rate.

4. The heart rate monitor according to any one of claim 1 through claim 3, further comprising:

a head band fitted to a head of a human body,

wherein said light-emitting element, said light-receiving element, said CPU, and said display unit are attached to said head band.

5. The heart rate monitor according to any one of claim 1 through claim 3, further comprising:

an eyeglass frame fitted to a head of a human body,

wherein said light-emitting element, said light-receiving element, said CPU and said display unit are attached to said eyeglass frame.

6. The heart rate monitor according to any one of claim 1 through claim 3, further comprising:

a sun visor fitted to a head of a human body,

wherein said light-emitting element, said light receiving element, said CPU and said display unit are attached to said sun visor.

7. The heart rate monitor according to any one of claim 1 through claim 3, further comprising:

a container engaged in an ear pinna of a human body,

wherein said light-emitting element, said light-receiving element, said CPU and said display unit are attached to said container.

8. A method of measuring a heart rate comprising the steps of:

fitting a light-emitting element and a light-receiving element to a human body;

reflecting or transmitting light emitted by said light-emitting element at or through blood running in a blood vessel and detecting it at said light-receiving element;

measuring a change in bloodstream running inside the blood vessel from a change in intensity of the light detected at said light-receiving element; and

calculating a pulse rate of the change in the bloodstream per unit time from the measured value and regarding the calculated pulse rate of the change in the blood stream per unit time as a heart rate,

wherein said light-emitting element and said light-receiving element are fitted to a head of a human body with a space of 4 mm to 10 mm between them, and

wherein light with a wavelength of 900 nm to 1200 nm emitted by said light-emitting element is reflected at or transmitted through a subcutaneous artery and/or blood running in the subcutaneous artery and is detected at said light receiving element.