| abstract |
(57) [Problem] To provide a photoacoustic signal measuring device suitable for measuring a substance to be measured contained in a target substance, for example, the water content of skin in vivo or in situ. SOLUTION: A semiconductor laser 11 having a measurement wavelength and a semiconductor laser 12 having a reference wavelength are alternately driven by the same modulation signal by driving means 13, and the modulated light is superimposed and guided to a cell 20 via an optical fiber 15. The sound wave generated by the substance to be measured absorbing light is picked up by the microphone 24, amplified by the preamplifier 25, and passed through the filter 16 to the signal processing device. Sent to 17. The signal processing device 17 continuously captures the digitized time-series data, and performs FFT on the frequency domain. Convert. The photoacoustic signal obtained corresponding to the measurement wavelength and the reference wavelength is intensity-corrected by the optical output signal, normalized, subtracted, and visualized by the output device 18. Signal processing device 17 Includes a processing unit 19 that performs a phase analysis of the photoacoustic signal. |