Biological information measuring apparatus and method for controlling the apparatus

• US 20060222224A1
• Filed: 02/09/2006
• Published: 10/05/2006
• Est. Priority Date: 02/09/2005
• Status: Active Grant

• Current Assignee: Spectratech, Inc.
• Original Assignee: Spectratech, Inc.
• Inventors: Ohashi, Mitsuo
• Granted Patent: US 7,729,732 B2
• Time in Patent Office: Days
• US Class Current: 382/128
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14553 specially adapted for cerebral tissue
• CPC Class Codes: A61B 5/4869 Determining body composition
• CPC Class Codes: G01N 2021/1785 Three dimensional
• CPC Class Codes: G01N 2021/3144 for oxymetry
• CPC Class Codes: G01N 2021/3148 using three or more wavelengths
• CPC Class Codes: G01N 21/359 using near infrared light
• CPC Class Codes: G01N 21/4795 spatially resolved investigating of object in scattering medium in vivo A61B
• CPC Class Codes: G01N 2201/0691 Modulated (not pulsed supply)

Abstract

A biological information measuring apparatus includes a plurality of light emission sections, a plurality of light detection sections, and a control section. Each light emission section injects, into a living organism, a spectrum-modulated light beam having a specific wavelength. The control section acquires a spread code sequence employed by each of the light emission sections for spread spectrum modulation, and supplies the spread code sequence to the light detection sections. By use of the spread code sequence, each light detection section selectively receives a specific reflected light beam having the spread code sequence, which is selected from among the light beams which have been emitted from the light emission sections and reflected in the living organism. Subsequently, each light detection section despreads an electrical signal corresponding to the thus-received reflected light beam, and outputs a detection signal corresponding to the intensity of the reflected light beam.

Claims

1. A biological information measuring apparatus comprising:

a plurality of light emission means, each adapted for modulating a predetermined primary modulated signal by spread spectrum modulation to thereby generate a secondary modulated signal, and for injecting a light beam into a living organism on the basis of the secondary modulated signal;

light detection means for receiving the light beams which have been emitted from the plurality of light emission means and transmitted through the living organism, for obtaining an electrical signal corresponding to the light beams through despreading, and for detecting a signal contained in the light beams on the basis of the electrical signal; and

control means for controlling the operation of the light emission means and the light detection means, and for obtaining biological information associated with the metabolism of the living organism on the basis of the signal detected by the light detection means, wherein

the control means comprises;

spread code sequence acquisition means for acquiring, from specific light emission means selected from among the plurality of light emission means, a spread code sequence employed by the specific light emission means for spread spectrum modulation of the predetermined primary modulated signal; and

spread code sequence supply means for supplying, to the light detection means, the spread code sequence acquired by the spread code sequence acquisition means.

2. A biological information measuring apparatus according to claim 1, wherein

the plurality of light emission means comprise a plurality of light generation means for respectively generating light beams having different specific wavelengths, and

each of the light generation means comprises:

spread code sequence generation means for generating the spread code sequence;

spread spectrum modulation means for generating the secondary modulated signal through spread spectrum modulation of the predetermined primary modulated signal supplied from the control means by use of the above-generated spread code sequence; and

light source driving means for driving a light source which emits a light beam having a specific wavelength on the basis of the secondary modulated signal generated by the spread spectrum modulation means.

3. A biological information measuring apparatus according to claim 2, wherein

the spread code sequence generation means comprises

periodic random number acquisition means for acquiring periodic random numbers supplied from the control means, and

a frequency synthesizer for generating a random pattern regarding frequency in accordance with the above-acquired periodic random numbers.

4. A biological information measuring apparatus according to claim 2, wherein

the spread code sequence generation means generates the spread code sequence by varying a chip frequency represented by the inverse number of the duration of occurrence of the spread code sequence.

5. A biological information measuring apparatus according to claim 2, wherein

the light beams having different specific wavelengths which are respectively generated by the plurality of light generation means enter the living organism while being superposed on one another.

6. A biological information measuring apparatus according to claim 1, wherein

the light detection means comprises:

light receiving means for receiving the light beams which have been transmitted through the living organism and generating an electrical signal corresponding to the received light beams;

spread code sequence acquisition means for acquiring a spread code sequence supplied from the control means;

despreading means for despreading the electrical signal by use of the thus-acquired spread code sequence, and for demodulating a signal contained in the light beams transmitted through the living organism; and

output means for outputting the thus-demodulated signal to the control means.

7. A biological information measuring apparatus according to claim 1, wherein

the light emission means and the light detection means are arranged in the form of a matrix.

8. A biological information measuring apparatus according to claim 1, wherein

the light emission means and the light detection means are connected to the living organism via light conducting means.

9. A method for controlling a biological information measuring apparatus comprising a plurality of light emission means, each adapted for modulating a predetermined primary modulated signal by spread spectrum modulation to thereby generate a secondary modulated signal, and for injecting a light beam into a living organism on the basis of the secondary modulated signal;

light detection means for receiving the light beams which have been emitted from the plurality of light emission means and transmitted through the living organism, for obtaining an electrical signal corresponding to the light beams through despreading, and for detecting a signal contained in the light beams on the basis of the electrical signal; and

control means for controlling the operation of the light emission means and the light detection means, and for obtaining biological information associated with the metabolism of the living organism on the basis of the signal detected by the light detection means, the method comprising controlling the control means to select specific light emission means from among the plurality of light emission means, to acquire a spread code sequence employed by the thus-selected specific light emission means for spread spectrum modulation of the predetermined primary modulated signal, and to supply the thus-acquired spread code sequence to the light detection means.

10. A method for controlling a biological information measuring apparatus according to claim 9, wherein

when biological information is measured in a depth direction of the living organism, the control means selects, as specific light emission means from among the plurality of light emission means, light emission means whose distance from the light detection means becomes equal to one of various distances.

11. A method for controlling a biological information measuring apparatus according to claim 9, wherein

the control means generates, for the specific light emission means, the spread code sequence employed by the specific light emission means for spread spectrum modulation of the predetermined primary modulated signal by varying a chip frequency represented by the inverse number of the duration of occurrence of the spread code sequence.