Constituent concentration measuring apparatus and constituent concentration measuring apparatus controlling method

• US 8,332,006 B2
• Filed: 05/02/2005
• Issued: 12/11/2012
• Est. Priority Date: 05/06/2004
• Status: Active Grant

• Current Assignee: Nippon Telegraph and Telephone Corporation
• Original Assignee: Nippon Telegraph and Telephone Corporation
• Inventors: Naganuma, Kazunori, Tajima, Takuro, Okabe, Yuichi, Sudo, Shoichi
• Primary Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US11/568,110
• Publication Number:
  US 20070197886A1
• Time in Patent Office: 2,780 Days
• Field of Search: 600/310, 600/322, 600/323
• US Class Current: 600/310
• CPC Class Codes: A61B 5/0095 by applying light and detecting acoustic waves, i.e. photoacoustic measurements
• 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 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/6826 Finger
• CPC Class Codes: A61B 5/6838 Clamps or clips
• CPC Class Codes: G01N 21/1702 with opto-acoustic detection, e.g. for gases or analysing solids
• CPC Class Codes: G01N 29/2418 using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics photoacoustic cells G01N21/1702; measuring characteristics of vibrations by using radiation-sensitive means G01H9/00; acousto-optical conversion techniques for short-range imaging G01S15/8965; sound-producing devices using laser bundle G10K15/046
• CPC Class Codes: G01N 29/2425 optoacoustic fluid cells therefor
• CPC Class Codes: G01N 29/449 Statistical methods not provided for in G01N29/4409, e.g. averaging, smoothing and interpolation

Abstract

An object of the present invention is to provide a noninvasive constituent concentration measuring apparatus and constituent concentration measuring apparatus controlling method, in which accurate measurement can be performed by superimposing two photoacoustic signals having the same frequency and reverse phases to nullify the effect from the other constituent occupying large part of the object to be measured. The constituent concentration measuring apparatus according to the invention includes light generating means for generating two light beams having different wavelengths, modulation means for electrically intensity-modulating each of the two light beams having different wavelengths using signals having the same frequency and reverse phases, light outgoing means for outputting the two intensity-modulated light beams having different wavelengths toward a test subject, and acoustic wave detection means for detecting an acoustic wave generated in the test subject by the outputted light.

Claims

1. A constituent concentration measuring apparatus characterized by comprising:

light generating means for generating two light beams having different wavelengths;

light modulation means for electrically intensity-modulating each of the two light beams having the mutually different wavelengths using signals having the same frequency and reverse phases;

light outgoing means for outputting the two intensity-modulated light beams having the mutually different wavelengths toward a test subject;

acoustic wave detection means for detecting an acoustic wave emitted in said test subject by the outputted light; and

constituent concentration computation means for computing a constituent concentration of a constituent from pressure of the detected acoustic wave, the constituent being set as a measuring object in said test subject, wherein

said constituent concentration computation means divides pressure of the acoustic wave, which is emitted by irradiating said two light beams having the mutually different wavelengths to said test subject, by pressure of the acoustic wave which is emitted when one of said two light beams is set to zero power.

2. A constituent concentration measuring apparatus as claimed in claim 1, characterized by further comprising second light outgoing means for outputting the light toward said test subject, the light being intermittently emitted at intervals which are longer than the repetition period for said same frequency.

3. A constituent concentration measuring apparatus as claimed in claim 2, characterized in that light from said second light outgoing means has a wavelength which exhibits a characteristic absorption of a constituent different from the constituent set as the measuring object.

4. A constituent concentration measuring apparatus as claimed in claim 2, characterized in that the light from said second light outgoing means has a wavelength which exhibits a characteristic absorption of hemoglobin in blood.

5. A constituent concentration measuring apparatus as claimed in claim 2, characterized in that said second light outgoing means emits the light at an interval that restricts a temperature rise in said test subject to 2°

C. or less.

6. A constituent concentration measuring apparatus as claimed in claim 2, characterized in that said second light outgoing means emits the light at an intensity that restricts a temperature rise in said test subject to 2°

C. or less.

7. A constituent concentration measuring apparatus as claimed in claim 1 or 2, characterized by further comprising a coupler between said light outgoing means and said test subject, the coupler combining the outgoing light beams.

8. A constituent concentration measuring apparatus as claimed in claim 1 or 2, characterized by further comprising rectifying amplification means for detecting amplitude of the acoustic wave from said acoustic wave detection means.

9. A constituent concentration measuring apparatus as claimed in claim 8, characterized in that said rectifying amplification means is a phase sensitive amplifier.

10. A constituent concentration measuring apparatus as claimed in claim 1 or 2, characterized in that diameters of the two outgoing light beams from said light outgoing means are substantially equal to each other.

11. A constituent concentration measuring apparatus as claimed in claim 1, characterized by further comprising:

frequency sweep means for sweeping a modulation frequency, the light generated by said light generating means being modulated in the modulation frequency; and

integration means for integrating the acoustic wave in a swept modulation frequency range, the acoustic wave being detected by said acoustic wave detection means,

the constituent concentration measuring apparatus characterized in that light modulation means electrically intensity-modulates each of said two light beams having the mutually different wavelengths using the signal from said frequency sweep means and with mutually reverse modulation phases.

12. A constituent concentration measuring apparatus as claimed in claim 11, characterized in that

said acoustic wave detection means tracks the modulation frequency to detect the acoustic wave emitted in the said test subject by the outputted light, the modulation frequency being swept by said frequency sweep means, and

said integration means integrates the acoustic wave in the modulation frequency range where said acoustic wave detection means has high detection sensitivity, the acoustic wave being detected by said acoustic wave detection means.

13. A constituent concentration measuring apparatus as claimed in claim 11, characterized by further comprising constituent concentration computation means for computing a constituent concentration of a constituent from the acoustic wave integrated by said integration means, the constituent being set as a measuring object in the said test subject.

14. A constituent concentration measuring apparatus as claimed in claim 1 or 11, characterized by further comprising recording means for recording the acoustic wave as a function of the modulation frequency, the acoustic wave being detected by said acoustic wave detection means.

15. A constituent concentration measuring apparatus as claimed in claim 1, characterized by further comprising an acoustic wave generator which outputs an acoustic wave,

the constituent concentration measuring apparatus characterized in that said acoustic wave detection means detects the acoustic wave emitted from said test subject as well as said acoustic wave transmitted from said acoustic wave generator through the test subject.

16. A constituent concentration measuring apparatus as claimed in claim 15, characterized by further comprising drive means for varying at least one of positions of said acoustic wave generator and said acoustic wave detection means.

17. A constituent concentration measuring apparatus as claimed in claim 16, characterized by further comprising control means for controlling said drive means such that intensity of the acoustic wave detected by said acoustic wave detection means becomes a particular value.

18. A constituent concentration measuring apparatus as claimed in claim 15, characterized in that said light outgoing means is fixed to said acoustic wave generator so as to keep the relative position to said acoustic wave generator.

19. A constituent concentration measuring apparatus as claimed in claim 15, characterized by further comprising pressing means for pressing said acoustic wave generator and said acoustic wave detection means against said test subject with pressing force whose pressure can be controlled.

20. A constituent concentration measuring apparatus as claimed in claim 15, characterized in that said acoustic wave generator is placed in proximity to the intensity modulated light beam outputted from said light outgoing means.

21. A constituent concentration measuring apparatus as claimed in claim 15, characterized by further comprising a transmission window in a part of said acoustic wave generator, the transmission window transmitting said intensity modulated light beam.

22. A constituent concentration measuring apparatus as claimed in claim 15, characterized in that the frequency and/or the intensity of said outputted acoustic wave from said acoustic wave generator is variable.

23. A constituent concentration measuring apparatus as claimed in claim 15, characterized by further comprising an acoustic coupling element on the surface of said acoustic wave generator and/or said light outgoing means, the surface is configured to be in contact with said test subject, the acoustic coupling element having an acoustic impedance configured to be substantially equal to that of said test subject.

24. A constituent concentration measuring apparatus as claimed in claim 1, characterized in that said light generating means sets the light wavelengths of said two light beams to two wavelength where an absorption difference exhibited by the constituent set as the measuring object is larger than the absorption difference exhibited by a solvent.

25. A constituent concentration measuring apparatus as claimed in claim 1, characterized in that said light generating means sets one of the light wavelengths of said two light beams to a light wavelength where the constituent set as the measuring object exhibits characteristic absorption, and said light generating means sets the other light wavelength to a wavelength where the solvent exhibits an equal absorption to that for said one of the light wavelengths.

26. A constituent concentration measuring apparatus as claimed in claim 24 or 25, characterized in that the light wavelengths of said two light beams are set to two wavelengths where an absorption difference exhibited by the constituent set as the measuring object is larger than the absorption difference exhibited by other constituents.

27. A constituent concentration measuring apparatus as claimed in claim 1, characterized in that said light generating means sets the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by a water.

28. A constituent concentration measuring apparatus as claimed in claim 27, characterized in that the light wavelengths of said two light beams are set to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by other blood constituents.

29. A constituent concentration measuring apparatus as claimed in claim 1, characterized in that said light generating means sets one of the light wavelengths of said two light beams to a light wavelength where the blood constituent set as the measuring object exhibits characteristic absorption, and said light generating means sets the other light wavelength to a wavelength where a water exhibits an equal absorption to that for said one of the light wavelengths.

30. A constituent concentration measuring apparatus as claimed in claim 29, characterized in that the light wavelengths of said two light beams are set to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by other blood constituents.

31. A constituent concentration measuring apparatus as claimed in claim 1, characterized in that said light modulation means operates at the same frequency as a resonant frequency concerning detection of the acoustic wave generated in said test subject.

32. A constituent concentration measuring apparatus as claimed in claim 1, characterized in that said acoustic wave detection means is synchronized with said modulation frequency to detect the acoustic wave by phase sensitive detection.

33. A constituent concentration measuring apparatus as claimed in claim 1, characterized in that said light generating means and said light modulation consists of two directly-modulated semiconductor laser light sources driven by rectangular-waveform signals having the same frequency and reverse phases.

34. A constituent concentration measuring apparatus as claimed in claim 1, characterized in that a blood constituent which is set as the measuring object is glucose or cholesterol.

35. A constituent concentration measuring apparatus as claimed in claim 1, characterized in that said light outgoing means and said acoustic wave detection means are arranged at positions substantially opposing to each other.

36. A constituent concentration measuring apparatus as claimed in claim 1, characterized by further comprising accessory means in which at least said light outgoing means and said acoustic wave detection means are arranged in a portion which comes into contact with said test subject.

37. A constituent concentration measuring apparatus as claimed in claim 36, characterized in that said light outgoing means and said acoustic wave detection means are arranged at positions substantially opposing to each other in said accessory means.

38. A constituent concentration measuring apparatus as claimed in claim 36, characterized in that a layer of cushioning material covers at least a semicircular portion configured to be in contact with the test subject inside said accessory means, the semicircular portion comprising a position where said acoustic wave detection means is inlaid, the cushioning material having acoustic impedance configured to be approximately equal to that of the test subject.

39. A constituent concentration measuring apparatus as claimed in claim 38, characterized in that a space between said layer of cushioning material and an inner surface of said accessory means is filled with a sound absorbing material.

40. A constituent concentration measuring apparatus as claimed in claim 36, characterized in that said light generating means generates two light beams having different wavelengths by multiple semiconductor laser devices.

41. A constituent concentration measuring apparatus as claimed in claim 36, characterized in that said light outgoing means includes a beam expander which enlarges the light beam diameter generated by said light generating means.

42. A constituent concentration measuring apparatus as claimed in claim 36, characterized in that said accessory means is a ring configured to be in contact with a human finger, said light outgoing means is configured to be arranged on a dorsal side of said finger, while said acoustic wave detection means is configured to be arranged on a palm side of said finger.

43. A constituent concentration measuring apparatus as claimed in claim 36, characterized in that said accessory means is a bracelet configured to be in contact with a human arm, said light outgoing means is configured to be arranged on a palm side of a hand, and said acoustic wave detection means is configured to be arranged on a dorsal side of a hand.

44. A constituent concentration measuring apparatus controlling method characterized by sequentially comprising:

a light generating procedure in which light generating means generates two light beams having different wavelengths;

a light modulation procedure in which light modulation means electrically intensity-modulates each of the two light beams having the mutually different wavelengths using signals having the same frequency and reverse phases, the two light beams having the mutually different wavelengths being generated in said light generating procedure;

a light outgoing procedure in which light outgoing means outputs the two intensity-modulated light beams having the mutually different wavelengths, which are intensity-modulated in said light modulation procedure;

an acoustic wave detection procedure in which acoustic wave detection means detects an acoustic wave generated by the light emitted in said light outgoing procedure; and

a constituent concentration computation procedure for computing the concentration of a constituent from pressure of the acoustic wave detected by said acoustic wave detection, the constituent being set as a measuring object,

wherein said constituent concentration computation procedure is a procedure for measuring pressure of the acoustic wave generated by said two light beams having the mutually different wavelengths, and the pressure of the acoustic wave generated when one of said two light beams is set to zero power, and then diving the pressure of the acoustic wave generated by said two light beams by the pressure of the acoustic wave generated when one of said two light beams is set to zero power.

45. A constituent concentration measuring apparatus controlling method as claimed in claim 44, further comprising a second light outgoing procedure in which second light outgoing means outputs the light intermittently emitted at intervals which are longer than the repetition period for said same frequency,

the constituent concentration measuring apparatus controlling method characterized in that, in said acoustic wave detection procedure, said acoustic wave detection means detects the acoustic wave generated by the light beams outputted in said light outgoing procedure and said second light outgoing procedure.

46. A constituent concentration measuring apparatus controlling method as claimed in claim 45, characterized in that said second light outgoing means emits the light having a wavelength which exhibits a characteristic absorption of a constituent different from the constituent set as the measuring object.

47. A constituent concentration measuring apparatus controlling method as claimed in claim 45, characterized in that said second light outgoing means emits the light having a wavelength which exhibits a characteristic absorption of hemoglobin in blood.

48. A constituent concentration measuring apparatus controlling method as claimed in claim 45, characterized in that said second light outgoing means emits the light at intervals during which temperature rise of 2°

C. or less is resulted in the test subject.

49. A constituent concentration measuring apparatus controlling method as claimed in claim 45, characterized in that said second light outgoing means emits the light of an intensity by which temperature rise of 2°

C. or less is resulted in the test subject.

50. A constituent concentration measuring apparatus controlling method as claimed in claim 44 or 45, characterized in that the two light beams are combines and irradiated from said light outgoing means.

51. A constituent concentration measuring apparatus controlling method as claimed in claim 44 or 45, characterized in that said detected acoustic wave is further rectified and amplified to detect amplitude of the acoustic wave.

52. A constituent concentration measuring apparatus controlling method as claimed in claim 51, characterized in that said rectifying amplification is phase sensitive amplification.

53. A constituent concentration measuring apparatus controlling method as claimed in claim 44 or 45, characterized in that diameters of the two light beams from said light outgoing means are substantially equal to each other.

54. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized by further comprising:

a frequency sweep procedure in which frequency sweep means sweeps a modulation frequency, the light generated in said light generating procedure being modulated in the modulation frequency; and

an integration procedure in which integration means integrates the acoustic wave in a swept modulation frequency range, the acoustic wave being detected in said acoustic wave detection procedure.

55. A constituent concentration measuring apparatus controlling method as claimed in claim 54, characterized in that,

in said acoustic wave detection procedure, the modulation frequency swept in said frequency sweep procedure is tracked to detect the acoustic wave emitted by the irradiated light, and

in said integration procedure, the acoustic wave is integrated in the modulation frequency range having high detection sensitivity in said acoustic wave detection procedure, the acoustic wave being detected by said acoustic wave detection procedure.

56. A constituent concentration measuring apparatus controlling method as claimed in claim 54, characterized by further comprising a constituent concentration computation procedure for computing a constituent concentration of a constituent from the acoustic wave integrated by said integration procedure, the constituent being set as a measuring object.

57. A constituent concentration measuring apparatus controlling method as claimed in claim 44 or 54, characterized in that said light generating procedure is a procedure for setting one of the light wavelengths of said two light beams to a light wavelength where the blood constituent set as the measuring object exhibits characteristic absorption while the other light wavelength is set to a wavelength where a water exhibits an equal absorption to that for said one of the light wavelengths.

58. A constituent concentration measuring apparatus controlling method as claimed in claim 57, characterized in that said light generating procedure is a procedure for setting the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by other blood constituents.

59. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized in that said light outgoing procedure and said acoustic wave detection procedure are performed in a container which is filled with an acoustic matching substance having an acoustic impedance substantially equal to that of a test subject.

60. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized by further comprising an optimum position detection procedure in which acoustic wave generators output acoustic waves from two or more different positions and acoustic wave detection means detects a position where intensity of said acoustic wave transmitted through said test subject becomes a particular value.

61. A constituent concentration measuring apparatus controlling method as claimed in claim 60, characterized in that said light outgoing means outputs the light from the position where intensity of said acoustic wave becomes the particular value.

62. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized in that said light generating procedure is a procedure for setting the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the constituent set as a measuring object is larger than the absorption difference exhibited by a solvent.

63. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized in that said light generating procedure is a procedure in which one of the light wavelengths of said two light beams is set to a wavelength where the constituent set as the measuring object exhibits characteristic absorption while the other light wavelength is set to a wavelength in which the solvent exhibits an equal absorption to that for said one of the light wavelengths.

64. A constituent concentration measuring apparatus controlling method as claimed in claim 62 or 63, characterized in that said light generating procedure is a procedure in which the light wavelengths of said two light beams are set to two wavelengths where an absorption difference exhibited by the liquid constituent set as the measuring object is larger than the absorption difference exhibited by other liquid constituents.

65. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized in that said light generating procedure is a procedure for setting the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by a water.

66. A constituent concentration measuring apparatus controlling method as claimed in claim 65, characterized in that said light generating procedure is a procedure for setting the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by other blood constituents.

67. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized in that said light modulation procedure is a procedure for performing modulation with the same frequency as a resonant frequency concerning detection of the generated acoustic wave.

68. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized in that said acoustic wave detection procedure is a procedure for synchronizing with said modulation frequency to detect the acoustic wave by phase sensitive detection.

69. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized in that said light generating procedure and said light modulation procedure are a procedure for directly modulating each of the two semiconductor laser light sources using the rectangular-waveform signals having the same frequency and reverse phases.

70. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized in that a blood constituent which is set as the measuring object, is glucose or cholesterol.

71. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized by further comprising a recording procedure after said acoustic wave detection procedure, recording procedure recording the acoustic wave as a function of the modulation frequency, the acoustic wave being detected by said acoustic wave detection procedure.

72. A constituent concentration measuring apparatus controlling method as claimed in claim 44, characterized in that, in said light outgoing procedure, a test subject is placed in contact with an outgoing surface of said intensity modulated light.

73. A constituent concentration measuring apparatus characterized by comprising:

light generating means for generating two light beams having different wavelengths;

light modulation means for electrically intensity-modulating each of the two light beams having the mutually different wavelengths using signals having the same frequency and reverse phases;

light outgoing means for outputting the two intensity-modulated light beams having the mutually different wavelengths toward a test subject; and

acoustic wave detection means for detecting an acoustic wave emitted in said test subject by the outputted light,

wherein said light generating means adjusts relative intensity of said two light beams having the mutually different wavelengths such that pressure of the acoustic wave becomes zero, the acoustic wave being generated by combining said two intensity-modulated light beams having the different wavelengths into a single light beam to irradiate water.

74. A constituent concentration measuring apparatus as claimed in claim 73, characterized by further comprising second light outgoing means for outputting the light toward said test subject, the light being intermittently emitted at intervals which are longer than the repetition period for said same frequency.

75. A constituent concentration measuring apparatus as claimed in claim 74, characterized in that light from said second light outgoing means has a wavelength which exhibits a characteristic absorption of a constituent different from the constituent set as the measuring object.

76. A constituent concentration measuring apparatus as claimed in claim 74, characterized in that the light from said second light outgoing means has a wavelength which exhibits a characteristic absorption of hemoglobin in blood.

77. A constituent concentration measuring apparatus as claimed in claim 74, characterized in that said second light outgoing means emits the light at an interval that restricts a temperature rise in said test subject to 2°

C. or less.

78. A constituent concentration measuring apparatus as claimed in claim 74, characterized in that said second light outgoing means emits the light at an intensity that restricts a temperature rise in said test subject to 2°

C. or less.

79. A constituent concentration measuring apparatus as claimed in claim 73 or 74, characterized by further comprising a coupler between said light outgoing means and said test subject, the coupler combining the outgoing light beams.

80. A constituent concentration measuring apparatus as claimed in claim 73 or 74, characterized by further comprising rectifying amplification means for detecting amplitude of the acoustic wave from said acoustic wave detection means.

81. A constituent concentration measuring apparatus as claimed in claim 80, characterized in that said rectifying amplification means is a phase sensitive amplifier.

82. A constituent concentration measuring apparatus as claimed in claim 73 or 74, characterized in that diameters of the two outgoing light beams from said light outgoing means are substantially equal to each other.

83. A constituent concentration measuring apparatus as claimed in claim 73, characterized by further comprising:

frequency sweep means for sweeping a modulation frequency, the light generated by said light generating means being modulated in the modulation frequency; and

integration means for integrating the acoustic wave in a swept modulation frequency range, the acoustic wave being detected by said acoustic wave detection means,

the constituent concentration measuring apparatus characterized in that said light modulation means electrically intensity-modulates each of said two light beams having the mutually different wavelengths using the signal from said frequency sweep means and with mutually reverse modulation phases.

84. A constituent concentration measuring apparatus as claimed in claim 83, characterized in that

said acoustic wave detection means tracks the modulation frequency to detect the acoustic wave emitted in the said test subject by the outputted light, the modulation frequency being swept by said frequency sweep means, and

said integration means integrates the acoustic wave in the modulation frequency range where said acoustic wave detection means has high detection sensitivity, the acoustic wave being detected by said acoustic wave detection means.

85. A constituent concentration measuring apparatus as claimed in claim 83, characterized by further comprising constituent concentration computation means for computing a constituent concentration of a constituent from the acoustic wave integrated by said integration means, the constituent being set as a measuring object in the said test subject.

86. A constituent concentration measuring apparatus as claimed in claim 73 or 83, characterized by further comprising recording means for recording the acoustic wave as a function of the modulation frequency, the acoustic wave being detected by said acoustic wave detection means.

87. A constituent concentration measuring apparatus as claimed in claim 73, characterized by further comprising an acoustic wave generator which outputs an acoustic wave,

the constituent concentration measuring apparatus characterized in that said acoustic wave detection means detects the acoustic wave emitted from said test subject as well as said acoustic wave transmitted from said acoustic wave generator through the test subject.

88. A constituent concentration measuring apparatus as claimed in claim 87, characterized by further comprising drive means for varying at least one of positions of said acoustic wave generator and said acoustic wave detection means.

89. A constituent concentration measuring apparatus as claimed in claim 88, characterized by further comprising control means for controlling said drive means such that intensity of the acoustic wave detected by said acoustic wave detection means becomes a particular value.

90. A constituent concentration measuring apparatus as claimed in claim 87, characterized in that said light outgoing means is fixed to said acoustic wave generator so as to keep the relative position to said acoustic wave generator.

91. A constituent concentration measuring apparatus as claimed in claim 87, characterized by further comprising pressing means for pressing said acoustic wave generator and said acoustic wave detection means against said test subject with pressing force whose pressure can be controlled.

92. A constituent concentration measuring apparatus as claimed in claim 87, characterized in that said acoustic wave generator is placed in proximity to the intensity modulated light beam outputted from said light outgoing means.

93. A constituent concentration measuring apparatus as claimed in claim 87, characterized by further comprising a transmission window in a part of said acoustic wave generator, the transmission window transmitting said intensity modulated light beam.

94. A constituent concentration measuring apparatus as claimed in claim 87, characterized in that the frequency and/or the intensity of said outputted acoustic wave from said acoustic wave generator is variable.

95. A constituent concentration measuring apparatus as claimed in claim 87, characterized by further comprising an acoustic coupling element on the surface of said acoustic wave generator and/or said light outgoing means, the surface is configured to be in contact with said test subject, the acoustic coupling element having an acoustic impedance configured to be substantially equal to that of said test subject.

96. A constituent concentration measuring apparatus as claimed in claim 73, characterized in that said light generating means sets the light wavelengths of said two light beams to two wavelength where an absorption difference exhibited by the constituent set as the measuring object is larger than the absorption difference exhibited by a solvent.

97. A constituent concentration measuring apparatus as claimed in claim 73, characterized in that said light generating means sets one of the light wavelengths of said two light beams to a light wavelength where the constituent set as the measuring object exhibits characteristic absorption, and said light generating means sets the other light wavelength to a wavelength where the solvent exhibits an equal absorption to that for said one of the light wavelengths.

98. A constituent concentration measuring apparatus as claimed in claim 96 or 97, characterized in that the light wavelengths of said two light beams are set to two wavelengths where an absorption difference exhibited by the constituent set as the measuring object is larger than the absorption difference exhibited by other constituents.

99. A constituent concentration measuring apparatus as claimed in claim 73, characterized in that said light generating means sets the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by a water.

100. A constituent concentration measuring apparatus as claimed in claim 99, characterized in that the light wavelengths of said two light beams are set to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by other blood constituents.

101. A constituent concentration measuring apparatus as claimed in claim 73, characterized in that said light generating means sets one of the light wavelengths of said two light beams to a light wavelength where the blood constituent set as the measuring object exhibits characteristic absorption, and said light generating means sets the other light wavelength to a wavelength where a water exhibits an equal absorption to that for said one of the light wavelengths.

102. A constituent concentration measuring apparatus as claimed in claim 101, characterized in that the light wavelengths of said two light beams are set to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by other blood constituents.

103. A constituent concentration measuring apparatus as claimed in claim 73, characterized in that said light modulation means operates at the same frequency as a resonant frequency concerning detection of the acoustic wave generated in said test subject.

104. A constituent concentration measuring apparatus as claimed in claim 73, characterized in that said acoustic wave detection means is synchronized with said modulation frequency to detect the acoustic wave by phase sensitive detection.

105. A constituent concentration measuring apparatus as claimed in claim 73, characterized in that said light generating means and said light modulation consists of two directly-modulated semiconductor laser light sources driven by rectangular-waveform signals having the same frequency and reverse phases.

106. A constituent concentration measuring apparatus as claimed in claim 73, characterized in that a blood constituent which is set as the measuring object is glucose or cholesterol.

107. A constituent concentration measuring apparatus as claimed in claim 73, characterized in that said light outgoing means and said acoustic wave detection means are arranged at positions substantially opposing to each other.

108. A constituent concentration measuring apparatus as claimed in claim 73, characterized by further comprising accessory means in which at least said light outgoing means and said acoustic wave detection means are arranged in a portion which comes into contact with said test subject.

109. A constituent concentration measuring apparatus as claimed in claim 108, characterized in that said light outgoing means and said acoustic wave detection means are arranged at positions substantially opposing to each other in said accessory means.

110. A constituent concentration measuring apparatus as claimed in claim 108, characterized in that a layer of cushioning material covers at least a semicircular portion configured to be in contact with the test subject inside said accessory means, the semicircular portion comprising a position where said acoustic wave detection means is inlaid, the cushioning material having acoustic impedance configured to be approximately equal to that of the test subject.

111. A constituent concentration measuring apparatus as claimed in claim 110, characterized in that a space between said layer of cushioning material and an inner surface of said accessory means is filled with a sound absorbing material.

112. A constituent concentration measuring apparatus as claimed in claim 108, characterized in that said light generating means generates two light beams having different wavelengths by multiple semiconductor laser devices.

113. A constituent concentration measuring apparatus as claimed in claim 108, characterized in that said light outgoing means includes a beam expander which enlarges the light beam diameter generated by said light generating means.

114. A constituent concentration measuring apparatus as claimed in claim 108, characterized in that said accessory means is a ring configured to be in contact with a human finger, said light outgoing means is configured to be arranged on a dorsal side of said finger, while said acoustic wave detection means is configured to be arranged on a palm side of said finger.

115. A constituent concentration measuring apparatus as claimed in claim 108, characterized in that said accessory means is a bracelet configured to be in contact with a human arm, said light outgoing means is configured to be arranged on a palm side of a hand, and said acoustic wave detection means is configured to be arranged on a dorsal side of a hand.

116. A constituent concentration measuring apparatus controlling method characterized by sequentially comprising:

a light generating procedure in which light generating means generates two light beams having different wavelengths;

a light modulation procedure in which light modulation means electrically intensity-modulates each of the two light beams having the mutually different wavelengths using signals having the same frequency and reverse phases, the two light beams having the mutually different wavelengths being generated in said light generating procedure;

a light outgoing procedure in which light outgoing means outputs the two intensity-modulated light beams having the mutually different wavelengths, which are intensity-modulated in said light modulation procedure;

an acoustic wave detection procedure in which acoustic wave detection means detects an acoustic wave generated by the light emitted in said light outgoing procedure; and

an intensity adjustment procedure between said light modulation procedure and said light outgoing procedure, the intensity adjustment procedure adjusting relative intensity of said two light beams having the mutually different wavelengths such that pressure of the acoustic wave becomes zero, the acoustic wave being generated by combining said two intensity-modulated light beams having the different wavelengths into a single light beam to irradiate water.

117. A constituent concentration measuring apparatus controlling method as claimed in claim 116, further comprising a second light outgoing procedure in which second light outgoing means outputs the light intermittently emitted at intervals which are longer than the repetition period for said same frequency,

the constituent concentration measuring apparatus controlling method characterized in that, in said acoustic wave detection procedure, said acoustic wave detection means detects the acoustic wave generated by the light beams outputted in said light outgoing procedure and said second light outgoing procedure.

118. A constituent concentration measuring apparatus controlling method as claimed in claim 117, characterized in that said second light outgoing means emits the light having a wavelength which exhibits a characteristic absorption of a constituent different from the constituent set as the measuring object.

119. A constituent concentration measuring apparatus controlling method as claimed in claim 117, characterized in that said second light outgoing means emits the light having a wavelength which exhibits a characteristic absorption of hemoglobin in blood.

120. A constituent concentration measuring apparatus controlling method as claimed in claim 117, characterized in that said second light outgoing means emits the light at intervals during which temperature rise of 2°

C. or less is resulted in the test subject.

121. A constituent concentration measuring apparatus controlling method as claimed in claim 117, characterized in that said second light outgoing means emits the light of an intensity by which temperature rise of 2°

C. or less is resulted in the test subject.

122. A constituent concentration measuring apparatus controlling method as claimed in claim 116 or 117, characterized in that the two light beams are combines and irradiated from said light outgoing means.

123. A constituent concentration measuring apparatus controlling method as claimed in claim 116 or 117, characterized in that said detected acoustic wave is further rectified and amplified to detect amplitude of the acoustic wave.

124. A constituent concentration measuring apparatus controlling method as claimed in claim 123, characterized in that said rectifying amplification is phase sensitive amplification.

125. A constituent concentration measuring apparatus controlling method as claimed in claim 116 or 117, characterized in that diameters of the two light beams from said light outgoing means are substantially equal to each other.

126. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized by further comprising:

a frequency sweep procedure in which frequency sweep means sweeps a modulation frequency, the light generated in said light generating procedure being modulated in the modulation frequency; and

an integration procedure in which integration means integrates the acoustic wave in a swept modulation frequency range, the acoustic wave being detected in said acoustic wave detection procedure.

127. A constituent concentration measuring apparatus controlling method as claimed in claim 126, characterized in that,

in said acoustic wave detection procedure, the modulation frequency swept in said frequency sweep procedure is tracked to detect the acoustic wave emitted by the irradiated light, and

in said integration procedure, the acoustic wave is integrated in the modulation frequency range having high detection sensitivity in said acoustic wave detection procedure, the acoustic wave being detected by said acoustic wave detection procedure.

128. A constituent concentration measuring apparatus controlling method as claimed in claim 126, characterized by further comprising a constituent concentration computation procedure for computing a constituent concentration of a constituent from the acoustic wave integrated by said integration procedure, the constituent being set as a measuring object.

129. A constituent concentration measuring apparatus controlling method as claimed in claim 116 or 126, characterized in that said light generating procedure is a procedure for setting one of the light wavelengths of said two light beams to a light wavelength where the blood constituent set as the measuring object exhibits characteristic absorption while the other light wavelength is set to a wavelength where a water exhibits an equal absorption to that for said one of the light wavelengths.

130. A constituent concentration measuring apparatus controlling method as claimed in claim 129, characterized in that said light generating procedure is a procedure for setting the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by other blood constituents.

131. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized in that said light outgoing procedure and said acoustic wave detection procedure are performed in a container which is filled with an acoustic matching substance having an acoustic impedance substantially equal to that of a test subject.

132. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized by further comprising an optimum position detection procedure in which acoustic wave generators output acoustic waves from two or more different positions and acoustic wave detection means detects a position where intensity of said acoustic wave transmitted through said test subject becomes a particular value.

133. A constituent concentration measuring apparatus controlling method as claimed in claim 132, characterized in that said light outgoing means outputs the light from the position where intensity of said acoustic wave becomes the particular value.

134. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized in that said light generating procedure is a procedure for setting the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the constituent set as a measuring object is larger than the absorption difference exhibited by a solvent.

135. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized in that said light generating procedure is a procedure in which one of the light wavelengths of said two light beams is set to a wavelength where the constituent set as the measuring object exhibits characteristic absorption while the other light wavelength is set to a wavelength in which the solvent exhibits an equal absorption to that for said one of the light wavelengths.

136. A constituent concentration measuring apparatus controlling method as claimed in claim 134 or 135, characterized in that said light generating procedure is a procedure in which the light wavelengths of said two light beams are set to two wavelengths where an absorption difference exhibited by the liquid constituent set as the measuring object is larger than the absorption difference exhibited by other liquid constituents.

137. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized in that said light generating procedure is a procedure for setting the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by a water.

138. A constituent concentration measuring apparatus controlling method as claimed in claim 137, characterized in that said light generating procedure is a procedure for setting the light wavelengths of said two light beams to two wavelengths where an absorption difference exhibited by the blood constituent set as the measuring object is larger than the absorption difference exhibited by other blood constituents.

139. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized in that said light modulation procedure is a procedure for performing modulation with the same frequency as a resonant frequency concerning detection of the generated acoustic wave.

140. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized in that said acoustic wave detection procedure is a procedure for synchronizing with said modulation frequency to detect the acoustic wave by phase sensitive detection.

141. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized in that said light generating procedure and said light modulation procedure are a procedure for directly modulating each of the two semiconductor laser light sources using the rectangular-waveform signals having the same frequency and reverse phases.

142. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized in that a blood constituent which is set as the measuring object, is glucose or cholesterol.

143. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized by further comprising a recording procedure after said acoustic wave detection procedure, recording procedure recording the acoustic wave as a function of the modulation frequency, the acoustic wave being detected by said acoustic wave detection procedure.

144. A constituent concentration measuring apparatus controlling method as claimed in claim 116, characterized in that, in said light outgoing procedure, a test subject is placed in contact with an outgoing surface of said intensity modulated light.