PROBLEM TO BE SOLVED: To provide a constituent concentration measuring apparatus which measures constituent concentration of an object to be measured with high precision while preventing a temperature dependent deterioration of measurement precision.SOLUTION: The constituent concentration measuring apparatus 100 comprises a light modulating means 110 which electrically strength-modulates beams of light of two wavelengths by a signal of the same frequency and an opposite phase, a light multiplexing means 120 which multiplexes the beams of light of the two wavelengths modified by the light modifying means 110, a light radiating means 140 which radiates the light multiplexed by the light multiplexing means onto an object to be measured 199, a temperature measurement means 200 which measures the temperature of the object to be measured 199, and a sonic wave signal detecting means 150 which detects a photoacoustic signal generated at the object to be measured 199 by the light from the light radiating means 140, acquires a temperature change of the object to be measured 199 on the basis of the temperature of the object to be measured 199 measured by the temperature measurement means 200 and carries out correction on the basis of the temperature change.COPYRIGHT: (C)2008,JPO&INPIT【課題】本発明は、温度依存性による測定精度の低下を防止し、被測定物の成分濃度を高精度に測定可能な成分濃度測定装置を提供することを目的とする。【解決手段】本発明に係る成分濃度測定装置100は、異なる波長の2波の光を同一周波数で逆位相の信号によりそれぞれ電気的に強度変調する光変調手段110と、光変調手段110で変調された2波の光を合波する光合波手段120と、光合波手段で合波された光を被測定物199に出射する光出射手段140と、被測定物199の温度を測定する温度測定手段200と、光出射手段140からの光によって被測定物199から発生する光音響信号を検出し、温度測定手段200が測定する被測定物199の温度から被測定物199の温度変化を求め、温度変化に基づいて補正を行う音波検出手段150と、を備える。【選択図】図1
