Constituent Concentration Measuring Apparatus And Constituent Concentration Measuring Apparatus Controlling Method

• US 20070197886A1
• Filed: 05/02/2005
• Published: 08/23/2007
• 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, Okabe, Yuichi, Tajima, Takuro, Sudo, Shoichi
• Granted Patent: US 8,332,006 B2
• Time in Patent Office: Days
• US Class Current: 600/322
• 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

1-175. -175. (canceled)

176. A constituent concentration measuring apparatus characterized by comprising:

light generating means for generating light;

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

light modulation means for electrically intensity-modulating the light using a signal from said frequency sweep means, the light being generated by said light generating means;

light outgoing means for outputting said intensity-modulated light toward an object to be measured;

acoustic wave detection means for detecting an acoustic wave which is generated in the object to be measured by said outputted light; 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.

183. A constituent concentration measuring apparatus as claimed in claim 176, characterized in that said acoustic wave detection means tracks the modulation frequency to detect the acoustic wave emitted in the said object to be measured, 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.

185. A constituent concentration measuring apparatus as claimed in claim 176, characterized by further comprising liquid constituent concentration computation means for computing a constituent concentration of a liquid constituent from the acoustic wave integrated by said integration means, the liquid constituent being set as a measuring object in the said object to be measured.

199. A constituent concentration measuring apparatus as claimed in any one of claims 176, 177, 178, 180, 181 and 182, 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.

177. A constituent concentration measuring apparatus comprising:

light generating means for generating light;

light modulation means for electrically intensity-modulating the light at a constant frequency, the light being generated by the light generating means;

light outgoing means for outputting the intensity modulated light toward an object to be measured, the intensity modulated light being intensity-modulated by the light modulation means; and

acoustic wave detection means for detecting an acoustic wave which is emitted from the object to be measured irradiated with said intensity modulated light,

the constituent concentration measuring apparatus characterized in that an acoustic matching substance and said object to be measured can be arranged between said light outgoing means and said acoustic wave detection means, the acoustic matching substance having acoustic impedance substantially equal to that of said object to be measured.

179. A constituent concentration measuring apparatus as claimed in claim 177 or 178, characterized in that said light generating means generates two light beams having different wavelengths, and

said light modulation means intensity-modulates each of said light beams into the intensity modulated light beams, the intensity modulated light beams having the same frequency and reverse phases.

178. A constituent concentration measuring apparatus characterized by comprising:

light generating means for generating light;

light modulation means for electrically intensity-modulating the light at a constant frequency, the light being generated by the light generating means;

light outgoing means for outputting the intensity modulated light toward an object to be measured, the intensity modulated light being intensity-modulated by the light modulation means;

acoustic wave detection means for detecting an acoustic wave which is emitted from the object to be measured irradiated with said intensity modulated light; and

a container in which a space between said light outgoing means and said acoustic wave detection means is filled with an acoustic matching substance having acoustic impedance substantially equal to that of said object to be measured.

180. A constituent concentration measuring apparatus characterized by comprising:

light generating means for generating light;

light modulation means for electrically intensity-modulating the light at a constant frequency, the light being generated by the light generating means;

light outgoing means for outputting the intensity modulated light toward an object to be measured, the intensity modulated light being intensity-modulated by the light modulation means;

an acoustic wave generator which outputs an acoustic wave; and

acoustic wave detection means for detecting the acoustic wave emitted from the object to be measured, which is irradiated with said intensity modulated light, and said acoustic wave transmitted from said acoustic wave generator through the object to be measured.

188. A constituent concentration measuring apparatus as claimed in claim 180, characterized by further comprising drive means for varying at least one of positions of said acoustic wave generator and said acoustic wave detection means.

190. A constituent concentration measuring apparatus as claimed in claim 188, 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.

181. 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 an object to be measured; and

acoustic wave detection means for detecting an acoustic wave emitted from the object to be measured by the outputted light.

182. A constituent concentration measuring apparatus as claimed in claim 181, 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 said frequency sweep means and with mutually reverse modulation phases.

184. A constituent concentration measuring apparatus as claimed in claim 182, characterized in that said acoustic wave detection means tracks the modulation frequency to detect the acoustic wave emitted in the said object to be measured, 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.

186. A constituent concentration measuring apparatus as claimed in claim 182, characterized by further comprising liquid constituent concentration computation means for computing a constituent concentration of a liquid constituent from the acoustic wave integrated by said integration means, the liquid constituent being set as a measuring object in the said object to be measured.

187. A constituent concentration measuring apparatus as claimed in claim 181, 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 the object to be measured as well as said acoustic wave transmitted from said acoustic wave generator through the object to be measured.

189. A constituent concentration measuring apparatus as claimed in claim 187, characterized by further comprising drive means for varying at least one of positions of said acoustic wave generator and said acoustic wave detection means.

191. A constituent concentration measuring apparatus as claimed in claim 189, 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.

192. A constituent concentration measuring apparatus as claimed in claim 181, characterized in that said light generating means sets the light wavelengths of said two light beams to two light wavelengths where an absorption difference exhibited by the liquid constituent set as the measuring object is larger than the absorption difference exhibited by a solvent.

193. A constituent concentration measuring apparatus as claimed in claim 181 or, 182, characterized in that said light generating means sets one of the light wavelengths of said two light beams to a light wavelength where the liquid 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.

194. A constituent concentration measuring apparatus as claimed in claim 192, characterized in that 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.

195. A constituent concentration measuring apparatus as claimed in claim 193, characterized in that 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.

196. A constituent concentration measuring apparatus as claimed in claim 181, characterized by further comprising a coupler between said light outgoing means and said object to be measured, the coupler combining the outgoing light beams.

197. A constituent concentration measuring apparatus as claimed in claim 181, characterized by further comprising rectifying amplification means for detecting amplitude of the acoustic wave from said acoustic wave detection means.

198. A constituent concentration measuring apparatus as claimed in claim 181, characterized by further comprising liquid constituent concentration computation means for computing a constituent concentration of a liquid constituent from pressure of the detected acoustic wave, the liquid constituent being set as a measuring object in the said object to be measured.

200. A constituent concentration measuring apparatus characterized by comprising:

light generating means for generating light;

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

light modulation means for electrically intensity-modulating the light using a signal from said frequency sweep means, the light being generated by said light generating means;

light outgoing means for outputting said intensity-modulated light toward a test subject;

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

222. A constituent concentration measuring apparatus as claimed in claim 200, 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.

224. A constituent concentration measuring apparatus as claimed in claim 200, 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.

251. A constituent concentration measuring apparatus as claimed in claim 222, characterized by further comprising rectifying amplification means for detecting amplitude of the acoustic wave from said acoustic wave detection means.

253. A constituent concentration measuring apparatus as claimed in claim 251, characterized in that said rectifying amplification means is a phase sensitive amplifier.

263. A constituent concentration measuring apparatus as claimed in claim 200, 201 or 202, 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.

265. A constituent concentration measuring apparatus as claimed in claim 200, 201 or 202, characterized in that said light outgoing means and said acoustic wave detection means are arranged at positions substantially opposing to each other.

267. A constituent concentration measuring apparatus as claimed in claim 200, 201 or 202, characterized by further comprising a light shielding hood surrounding at least a part of the optical path of said intensity modulated light, the light shielding hood preventing said intensity modulated light from leaking to the outside of said constituent concentration measuring apparatus.

201. A constituent concentration measuring apparatus comprising:

light generating means for generating light;

light modulation means for electrically intensity-modulating the light at a constant frequency, the light being generated by the light generating means;

light outgoing means for outputting the intensity modulated light toward a test subject, the intensity modulated light being intensity-modulated by the light modulation means; and

acoustic wave detection means for detecting an acoustic wave which is emitted from said test subject irradiated with said intensity modulated light,

the constituent concentration measuring apparatus characterized in that an acoustic matching substance and said test subject can be arranged between said light outgoing means and said acoustic wave detection means, the acoustic matching substance having acoustic impedance substantially equal to that of said test subject.

202. A constituent concentration measuring apparatus characterized by comprising:

light generating means for generating light;

light modulation means for electrically intensity-modulating the light at a constant frequency, the light being generated by the light generating means;

light outgoing means for outputting the intensity modulated light toward a test subject, the intensity modulated light being intensity-modulated by the light modulation means;

acoustic wave detection means for detecting an acoustic wave which is emitted from said test subject irradiated with said intensity modulated light; and

a container in which a space between said light outgoing means and said acoustic wave detection means is filled with an acoustic matching substance having acoustic impedance substantially equal to that of said test subject.

203. A constituent concentration measuring apparatus as claimed in claim 202, characterized in that said container is filled with water as for said acoustic matching substance.

204. A constituent concentration measuring apparatus as claimed in claim 202, characterized in that said light generating means generates two light beams having different wavelengths, and said light modulation means intensity-modulates each of said light beams into the intensity modulated light beams, the intensity modulated light beams having the same frequency and reverse phases.

205. A constituent concentration measuring apparatus as claimed in claim 202, characterized in that a cross-sectional shape of said container is a semicircle, and said light outgoing means is positioned substantially at the center of said semicircle.

206. A constituent concentration measuring apparatus as claimed in claim 205, characterized in that said two or more acoustic wave detection means are arranged on an arc portion of said semicircle of said container.

207. A constituent concentration measuring apparatus as claimed in claim 202, characterized in that a cross-sectional shape of said container is an ellipse, and said light outgoing means and said acoustic wave detection means are positioned substantially at the focal points of said ellipse respectively.

208. A constituent concentration measuring apparatus as claimed in claim 202, characterized in that the bottom portion of said container forms a semi-ellipsoid containing the two focal points in sectional plane, and said light outgoing means and said acoustic wave detection means are positioned substantially at each of the two focal points of said semi-ellipsoid respectively.

209. A constituent concentration measuring apparatus as claimed in claim 207 or 208, characterized by comprising a reflection material on at least a part of the inner wall of said container.

210. A constituent concentration measuring apparatus as claimed in claim 202, characterized by comprising a sound absorbing material on at least a part of the inner wall of said container.

211. A constituent concentration measuring apparatus as claimed in claim 202, characterized by further comprising an outgoing window on the inner wall of said container, the outgoing window being transparent for said intensity modulated light.

212. A constituent concentration measuring apparatus as claimed in claim 202, characterized in that said light outgoing means includes an optical fiber which guides the intensity modulated light to said container.

213. A constituent concentration measuring apparatus as claimed in claim 202, characterized by further comprising:

temperature measuring means for measuring a temperature of said acoustic matching substance; and

temperature adjustment means for adjusting a temperature of said acoustic matching substance according to the temperature being measured by the temperature measuring means.

264. A constituent concentration measuring apparatus as claimed in claim 204, 215 or 221, 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.

266. A constituent concentration measuring apparatus as claimed in claim 204 or 215, characterized in that said light outgoing means and said acoustic wave detection means are arranged at positions substantially opposing to each other.

214. A constituent concentration measuring apparatus characterized by comprising:

light generating means for generating light;

light modulation means for electrically intensity-modulating the light at a constant frequency, the light being generated by the light generating means;

light outgoing means for outputting the intensity modulated light toward a test subject, the intensity modulated light being intensity-modulated by the light modulation means;

an acoustic wave generator which outputs an acoustic wave; and

acoustic wave detection means for detecting the acoustic wave emitted from said test subject which is irradiated with said intensity modulated light, as well as said acoustic wave transmitted from said acoustic wave generator through the test subject.

227. A constituent concentration measuring apparatus as claimed in claim 214, characterized by further comprising drive means for varying at least one of positions of said acoustic wave generator and said acoustic wave detection means.

229. A constituent concentration measuring apparatus as claimed in claim 227, 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.

231. A constituent concentration measuring apparatus as claimed in claim 214, 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.

233. A constituent concentration measuring apparatus as claimed in claim 214, 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.

235. A constituent concentration measuring apparatus as claimed in claim 214, characterized in that said acoustic wave generator is placed in proximity of the intensity modulated light beam outputted from said light outgoing means.

237. A constituent concentration measuring apparatus as claimed in claim 214, characterized by further comprising a transmission window in a part of said acoustic wave generator, the transmission window transmitting said intensity modulated light beam.

239. A constituent concentration measuring apparatus as claimed in claim 214, characterized in that the frequency and/or the intensity of said outputted acoustic wave from said acoustic wave generator is variable.

241. A constituent concentration measuring apparatus as claimed in claim 214, characterized by further comprising an acoustic coupling element on the surface of said acoustic wave generator and/or said light outgoing means, the surface being in contact with said test subject, the acoustic coupling element having an acoustic impedance substantially equal to that of said test subject.

215. 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.

216. A constituent concentration measuring apparatus as claimed in claim 215, 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.

217. A constituent concentration measuring apparatus as claimed in claim 216, 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.

218. A constituent concentration measuring apparatus as claimed in claim 216, characterized in that the light from said second light outgoing means has a wavelength which exhibits a characteristic absorption of hemoglobin in blood.

219. A constituent concentration measuring apparatus as claimed in claim 216, characterized in that an interval during which said second light outgoing means emits the light is an interval during which temperature rise of 2°

C. or less is resulted is generated in said test subject.

220. A constituent concentration measuring apparatus as claimed in claim 216, characterized in that light intensity of said second light outgoing means is an intensity by which temperature rise of 2°

C. or less is resulted in said test subject.

221. A constituent concentration measuring apparatus as claimed in claim 215, 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.

223. A constituent concentration measuring apparatus as claimed in claim 221, 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.

225. A constituent concentration measuring apparatus as claimed in claim 221, 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.

226. A constituent concentration measuring apparatus as claimed in claim 215, 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.

228. A constituent concentration measuring apparatus as claimed in claim 226, characterized by further comprising drive means for varying at least one of positions of said acoustic wave generator and said acoustic wave detection means.

230. A constituent concentration measuring apparatus as claimed in claim 228, 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.

232. A constituent concentration measuring apparatus as claimed in claim 226, 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.

234. A constituent concentration measuring apparatus as claimed in claim 226, 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.

236. A constituent concentration measuring apparatus as claimed in claim 226, characterized in that said acoustic wave generator is placed in proximity of to the intensity modulated light beam outputted from said light outgoing means.

238. A constituent concentration measuring apparatus as claimed in claim 226, characterized by further comprising a transmission window in a part of said acoustic wave generator, the transmission window transmitting said intensity modulated light beam.

240. A constituent concentration measuring apparatus as claimed in claim 226, characterized in that the frequency and/or the intensity of said outputted acoustic wave from said acoustic wave generator is variable.

242. A constituent concentration measuring apparatus as claimed in claim 226, characterized by further comprising an acoustic coupling element on the surface of said acoustic wave generator and/or said light outgoing means, the surface being in contact with said test subject, the acoustic coupling element having an acoustic impedance substantially equal to that of said test subject.

243. A constituent concentration measuring apparatus as claimed in claim 215, 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.

244. A constituent concentration measuring apparatus as claimed in claim 215, 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.

245. A constituent concentration measuring apparatus as claimed in claim 243 or 244, 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.

246. A constituent concentration measuring apparatus as claimed in claim 215, 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.

247. A constituent concentration measuring apparatus as claimed in claim 215 or 235, 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.

248. A constituent concentration measuring apparatus as claimed in claim 246, 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.

249. A constituent concentration measuring apparatus as claimed in claim 247, 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.

250. A constituent concentration measuring apparatus as claimed in claim 215 or 216, characterized by further comprising a coupler between said light outgoing means and said test subject, the coupler combining the outgoing light beams.

252. A constituent concentration measuring apparatus as claimed in claim 215 or 216, characterized by further comprising rectifying amplification means for detecting amplitude of the acoustic wave from said acoustic wave detection means.

254. A constituent concentration measuring apparatus as claimed in claim 252, characterized in that said rectifying amplification means is a phase sensitive amplifier.

255. A constituent concentration measuring apparatus as claimed in claim 215 or 216, characterized in that diameters of the two outgoing light beams from said light outgoing means are substantially equal to each other.

256. A constituent concentration measuring apparatus as claimed in claim 215, characterized by further comprising 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.

257. A constituent concentration measuring apparatus as claimed in claim 256, characterized in that 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.

258. A constituent concentration measuring apparatus as claimed in claim 215, 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.

259. A constituent concentration measuring apparatus as claimed in claim 215, characterized in that 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.

260. A constituent concentration measuring apparatus as claimed in claim 215, characterized in that said acoustic wave detection means is synchronized with said modulation frequency to detect the acoustic wave by phase sensitive detection.

261. A constituent concentration measuring apparatus as claimed in claim 215, 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.

262. A constituent concentration measuring apparatus as claimed in claim 215, characterized in that a blood constituent which is set as the measuring object is glucose or cholesterol.

268. A constituent concentration measuring apparatus as claimed in claim 215, characterized by further comprising enduing 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, the portion being located inside of an annular portion which is endured surrounding said test subject.

269. A constituent concentration measuring apparatus as claimed in claim 268, characterized in that said light outgoing means and said acoustic wave detection means are arranged at positions substantially opposing to each other on the annular portion of said enduing means.

270. A constituent concentration measuring apparatus as claimed in claim 268, characterized in that a layer of cushioning material covers at least a semicircular portion being in contact with the test subject inside the annular portion of said enduing means, the semicircular portion comprising position where said acoustic wave detection means is inlaid, the cushioning material having acoustic impedance approximately equal to that of the test subject.

271. A constituent concentration measuring apparatus as claimed in claim 270, characterized in that a space between said layer of cushioning material and a inner surface of the annular portion of said enduing means is filled with a sound absorbing material.

272. A constituent concentration measuring apparatus as claimed in any one of claims 268, characterized in that said light generating means generates two light beams having different wavelengths by multiple semiconductor laser devices.

273. A constituent concentration measuring apparatus as claimed in claim 268, characterized in that said light outgoing means includes a beam expander which enlarges the light beam diameter generated by said light generating means.

274. A constituent concentration measuring apparatus as claimed in claim 268, characterized in that said enduing means is a ring fitted in a human finger, said light outgoing means is arranged on a dorsal side of said finger, while said acoustic wave detection means is arranged on a palm side of said finger.

275. A constituent concentration measuring apparatus as claimed in claim 268, characterized in that said enduing means is a bracelet fitted in a human arm, said light outgoing means is arranged on a palm side of a hand, and said acoustic wave detection means is arranged on a dorsal side of a hand.

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

a light generating procedure in which light generating means generates light;

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;

a light modulation procedure in which light modulation means electrically intensity-modulates the light using a signal swept in said frequency sweep procedure, the light being generated in said light generating procedure;

a light outgoing procedure in which light outgoing means outputs the light toward an object to be measured, the light being intensity-modulated in said light modulation procedure;

an acoustic wave detection procedure in which acoustic wave detection means detects an acoustic wave which is generated in the object to be measured by the light outputted in said light outgoing procedure; 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.

281. A constituent concentration measuring apparatus controlling method as claimed in claim 276, characterized in that said acoustic wave detection procedure is a procedure in which the modulation frequency is tracked to detect the acoustic wave emitted in the said object to be measured by the irradiation light, the modulation frequency being swept in said frequency sweep procedure, and

said integration procedure is a procedure in which the acoustic wave is integrated in the modulation frequency range where detection sensitivity of the acoustic wave is high in said acoustic wave detection procedure, the acoustic wave being detected in said acoustic wave detection procedure.

283. A constituent concentration measuring apparatus controlling method as claimed in claim 276 or 281, characterized by further comprising a liquid constituent concentration computation procedure for computing a constituent concentration of a liquid constituent from the acoustic wave integrated in said integration procedure, the liquid constituent being set as a measuring object.

298. A constituent concentration measuring apparatus controlling method as claimed in any one of claims 276 to 279, characterized in that said detected acoustic wave is further rectified and amplified to detect amplitude of the acoustic wave.

299. A constituent concentration measuring apparatus controlling method as claimed in any one of claims 276 to 279, characterized by further comprising a liquid constituent concentration computation procedure for computing a constituent concentration of a liquid constituent from pressure of the acoustic wave detected in said acoustic wave detection procedure, the liquid constituent being set as a measuring object.

300. A constituent concentration measuring apparatus controlling method as claimed in any one of claims 276 to 280, characterized by further comprising a recording procedure for recording the acoustic wave as a function of the modulation frequency after said acoustic wave detection procedure, the acoustic wave being detected in said acoustic wave detection procedure.

301. A constituent concentration measuring apparatus controlling method as claimed in any one of claims 276 to 279, characterized in that, in said light outgoing procedure, an object to be measured is placed in contact with an outgoing surface of said intensity modulated light, and said object to be measured is directly irradiated with said intensity modulated light.

277. A constituent concentration measuring apparatus controlling method comprising:

a light generating procedure in which light generating means generates light;

a light modulation procedure in which light modulation means electrically intensity-modulates the light at a constant frequency, the light being generated by said light generating procedure;

a light outgoing procedure in which light outgoing means outputs the intensity modulated light toward an object to be measured, the intensity modulated light being intensity-modulated by said light modulation procedure; and

an acoustic wave detection procedure in which acoustic wave detection means detects an acoustic wave which is emitted from said object to be measured by said intensity modulated light in said light outgoing procedure, the constituent concentration measuring apparatus controlling method 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 age 28 of 44 substance having acoustic impedance substantially equal to that of the object to be measured.

286. A constituent concentration measuring apparatus controlling method as claimed in claim 277, characterized in that, in said acoustic wave detection procedure, said acoustic wave is detected through an acoustic matching substance having an acoustic impedance substantially equal to that of said object to be measured.

288. A constituent concentration measuring apparatus controlling method as claimed in claim 277, characterized in that, in said light outgoing procedure, said intensity modulated light is arranged on the inner wall of said container, and said intensity modulated light is outputted to said object to be measured through an outgoing window which is transparent for said intensity modulated light.

290. A constituent concentration measuring apparatus controlling method as claimed in claim 277, characterized in that, in said object to be measured, a region irradiated with said intensity modulated light is covered with said acoustic matching substance in either sol or gel form.

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

an optimum position detection procedure in which acoustic wave generators output acoustic waves from two or more different positions to object to be measured and acoustic wave detection means detects a position where intensity of said acoustic wave transmitted through said object to be measured becomes a particular value; and

an acoustic wave detection procedure in which light outgoing means outputs intensity modulated light to said object to be measured from the position where intensity of said acoustic wave becomes the particular value, the intensity modulated light being intensity-modulated at a constant frequency, and said acoustic wave detection means detects the acoustic wave emitted from said object to be measured.

279. 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 the mutually 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 being generated in the a light generating procedure;

a light outgoing procedure in which light outgoing means outputs the two light beams having the mutually different wavelengths to an object to be measured, the two light beams being intensity-modulated in the light modulation procedure; and

an acoustic wave detection procedure in which acoustic wave detection means detects an acoustic wave emitted from said object to be measured by the light outputted in said light outgoing procedure.

280. A constituent concentration measuring apparatus controlling method as claimed in claim 279, 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.

282. A constituent concentration measuring apparatus controlling method as claimed in claim 280, characterized in that said acoustic wave detection procedure is a procedure in which the modulation frequency is tracked to detect the acoustic wave emitted in the said object to be measured by the irradiation light, the modulation frequency being swept in said frequency sweep procedure, and

said integration procedure is a procedure in which the acoustic wave is integrated in the modulation frequency range where detection sensitivity of the acoustic wave is high in said acoustic wave detection procedure, the acoustic wave being detected in said acoustic wave detection procedure.

284. A constituent concentration measuring apparatus controlling method as claimed in claim 280 or 282, characterized by further comprising a liquid constituent concentration computation procedure for computing a constituent concentration of a liquid constituent from the acoustic wave integrated in said integration procedure, the liquid constituent being set as a measuring object.

285. A constituent concentration measuring apparatus controlling method as claimed in claim 279, 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 the object to be measured.

287. A constituent concentration measuring apparatus controlling method as claimed in claim 285, characterized in that, in said acoustic wave detection procedure, said acoustic wave is detected through an acoustic matching substance having an acoustic impedance substantially equal to that of said object to be measured,

289. A constituent concentration measuring apparatus controlling method as claimed in claim 285, characterized in that, in said light outgoing procedure, said intensity modulated light is arranged on the inner wall of said container, and said intensity modulated light is outputted to said object to be measured through an outgoing window which is transparent for said intensity modulated light.

291. A constituent concentration measuring apparatus controlling method as claimed in claim 285, characterized in that, in said object to be measured, a region irradiated with said intensity modulated light is covered with said acoustic matching substance in either sol or gel form.

292. A constituent concentration measuring apparatus controlling method as claimed in claim 279, further comprising an optimum position detection procedure in which acoustic wave generators output acoustic waves from two or more different positions to said object to be measured and acoustic wave detection means detects a position where intensity of said acoustic wave transmitted through said object to be measured becomes a particular value,

the constituent concentration measuring apparatus controlling method characterized in that said light outgoing means outputs intensity modulated light to said object to be measured from the position where intensity of said acoustic wave becomes the particular value.

293. A constituent concentration measuring apparatus controlling method as claimed in claim 279, characterized in that said light generating procedure is a procedure for setting the light wavelengths of said two light beams to two light wavelengths where an absorption difference exhibited by the liquid constituent set as the measuring object is larger than the absorption difference exhibited by a solvent.

294. A constituent concentration measuring apparatus controlling method as claimed in claim 279 or 280, 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 liquid constituent set as the measuring object exhibits characteristic absorption, and while the other light wavelength is set to a wavelength where the solvent exhibits an equal absorption to that for said one of the light wavelengths.

295. A constituent concentration measuring apparatus controlling method as claimed in claim 293, 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.

296. A constituent concentration measuring apparatus controlling method as claimed in claim 294, 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.

297. A constituent concentration measuring apparatus controlling method as claimed in claim 279, characterized in that the two light beams from said light outgoing means are combined and outputted to said object to be measured.

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

a light generating procedure in which light generating means generates light;

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;

a light modulation procedure in which light modulation means electrically intensity-modulates the light using a signal swept in said frequency sweep procedure, the light being generated in said light generating procedure;

a light outgoing procedure in which light outgoing means outputs the light intensity-modulated in said light modulation procedure;

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

312. A constituent concentration measuring apparatus controlling method as claimed in claim 302, 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.

314. A constituent concentration measuring apparatus controlling method as claimed in claim 302, 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.

343. A constituent concentration measuring apparatus controlling method as claimed in any one of claims 302 to 305, characterized in that a blood constituent which is set as the measuring object, is glucose or cholesterol.

344. A constituent concentration measuring apparatus controlling method as claimed in any one of claims 302, 303, 304, 305 and 312, 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.

345. A constituent concentration measuring apparatus controlling method as claimed in any one of claims 302 to 305, characterized in that, in said light outgoing procedure, a test subject is placed in contact with an outgoing surface of said intensity modulated light.

303. A constituent concentration measuring apparatus controlling method comprising:

a light generating procedure in which light generating means generates light;

a light modulation procedure in which light modulation means electrically intensity-modulates the light at a constant frequency, the light being generated in said light generating procedure;

a light outgoing procedure in which light outgoing means outputs the intensity modulated light intensity-modulated in said light modulation procedure; and

an acoustic wave detection procedure in which acoustic wave detection means detects an acoustic wave generated by said intensity modulated light in said light outgoing procedure,

the constituent concentration measuring apparatus controlling method characterized in that said light outgoing procedure and said acoustic wave detection procedure are performed in a container filled with an acoustic matching substance having an acoustic impedance substantially equal to that of a test subject.

317. A constituent concentration measuring apparatus controlling method as claimed in claim 303, characterized in that, in said acoustic wave detection procedure, said acoustic wave is detected through an acoustic matching substance having an acoustic impedance substantially equal to that of said test subject.

318. A constituent concentration measuring apparatus controlling method as claimed in claim 303, characterized in that, in said light outgoing procedure, said intensity modulated light is arranged on the inner wall surface of said container, and said intensity modulated light is outputted through an outgoing window which is transparent for said intensity modulated light.

319. A constituent concentration measuring apparatus controlling method as claimed in claim 303, characterized in that, in said test subject, a region irradiated with said intensity modulated light is covered with said acoustic matching substance in either sol or gel form.

320. A constituent concentration measuring apparatus controlling method as claimed in claim 303, characterized in that said container is filled with water as for said acoustic matching substance.

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

an optimum position detection procedure in which acoustic wave generators output acoustic waves from two or more different positions to a test subject and acoustic wave detection means detects a position where intensity of said acoustic wave transmitted through said test subject becomes a particular value; and

an acoustic wave detection procedure in which light outgoing means outputs intensity modulated light from the position where intensity of said acoustic wave transmitted through said test subject becomes the particular value, the intensity modulated light being intensity-modulated at a constant frequency, and said acoustic wave detection means detects the acoustic wave emitted by said intensity modulated light.

323. A constituent concentration measuring apparatus controlling method as claimed in claim 304, characterized in that, in said acoustic wave detection procedure, said light outgoing means emits the light through a transmission window furnished in a part of said acoustic wave generator, the transmission window being transparent for said intensity modulated light.

325. A constituent concentration measuring apparatus controlling method as claimed in claim 304, characterized in that, in said optimum position detection procedure, said acoustic wave generator and said acoustic wave detection means detect said acoustic wave by pressing said acoustic wave generator and said acoustic wave detection means against said test subject with pressing force whose pressure can be controlled.

305. 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; and

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.

306. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.

307. A constituent concentration measuring apparatus controlling method as claimed in claim 306, 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.

308. A constituent concentration measuring apparatus controlling method as claimed in claim 306, characterized in that said second light outgoing means emits the light having a wavelength which exhibits a characteristic absorption of hemoglobin in blood.

309. A constituent concentration measuring apparatus controlling method as claimed in claim 306, 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.

310. A constituent concentration measuring apparatus controlling method as claimed in claim 306, 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.

311. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.

313. A constituent concentration measuring apparatus controlling method as claimed in claim 311, 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.

315. A constituent concentration measuring apparatus controlling method as claimed in claim 311, 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.

316. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.

321. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.

322. A constituent concentration measuring apparatus controlling method as claimed in claim 321, characterized in that said light outgoing means outputs the light from the position where intensity of said acoustic wave becomes the particular value.

324. A constituent concentration measuring apparatus controlling method as claimed in claim 305, characterized in that, in said optimum position detection procedure, said acoustic wave generator outputs said acoustic wave having the substantially the same frequency as said intensity modulated light, or said acoustic wave generator increases or decreases the intensity of the acoustic wave outputted according to the intensity of said acoustic wave detected in said acoustic wave detection means.

326. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.

327. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.

328. A constituent concentration measuring apparatus controlling method as claimed in claim 326 or 327, 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.

329. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.

330. A constituent concentration measuring apparatus controlling method as claimed in claim 305 or 311, 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.

331. A constituent concentration measuring apparatus controlling method as claimed in claim 329, 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.

332. A constituent concentration measuring apparatus controlling method as claimed in claim 330, 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.

333. A constituent concentration measuring apparatus controlling method as claimed in claim 305 or 306, characterized in that the two light beams are combines and irradiated from said light outgoing means.

334. A constituent concentration measuring apparatus controlling method as claimed in claim 305 or 306, characterized in that said detected acoustic wave is further rectified and amplified to detect amplitude of the acoustic wave.

335. A constituent concentration measuring apparatus controlling method as claimed in claim 334, characterized in that said rectifying amplification is phase sensitive amplification.

336. A constituent concentration measuring apparatus controlling method as claimed in claim 305 or 306, characterized in that diameters of the two light beams from said light outgoing means are substantially equal to each other.

337. A constituent concentration measuring apparatus controlling method as claimed in claim 305, characterized by further comprising 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.

338. A constituent concentration measuring apparatus controlling method as claimed in claim 337, characterized in that 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.

339. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.

340. A constituent concentration measuring apparatus controlling method as claimed in claim 305, characterized by further comprising 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.

341. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.

342. A constituent concentration measuring apparatus controlling method as claimed in claim 305, 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.