Nippon Telegraph and Telephone Corporation

Takuro Tajima

Shoichi Sudo

Yuichi Okabe

Kazunori Naganuma

Yujiro Tanaka

Ryoichi Kasahara

Michiko Seyama

Nobuaki Matsuura

Kei Kuwabara

Takayuki Ogasawara

Masahito Nakamura

A light source that emits beam light, a beam shaping unit that shapes the beam light, and a pulse control unit that forms the beam light into pulse light are included. The light source emits beam light that has a wavelength that is to be absorbed by a measurement-target substance. The pulse control unit forms beam light that is emitted from the light source and with which a measurement-target part is irradiated, into pulse light that has a preset frequency and has a pulse width that is a reciprocal of twice the frequency. The beam shaping unit shapes the beam light so that a beam radius of the beam light that is emitted from the light source and with which the measurement-target part is to be irradiated is equal to a value obtained by dividing a speed of sound by π×f, where f denotes the frequency.

Photoacoustic analysis method and device

A component concentration measuring apparatus includes: a dielectric spectroscopy portion that irradiates a measurement subject with electromagnetic waves and measures a complex permittivity, thereby acquiring a dielectric spectroscopy spectrum; a temperature measurement portion that measures a temperature of the measurement subject; a signal processing portion that corrects the dielectric spectroscopy spectrum according to the temperature measured by the temperature measurement portion; and a calculating portion that applies a calibration model generated in advance from a dielectric spectroscopy spectrum of a sample whose component concentration is known, to the dielectric spectroscopy spectrum corrected by the signal processing portion, thereby calculating a component concentration of the measurement subject. A dielectric spectroscopy sensor that transmits and receives electromagnetic waves and a temperature sensor that outputs a signal that changes in accordance with a temperature are fixed to the measurement probe such that a certain distance is interposed between the sensors.

Component concentration measurement device and component concentration measurement method

A component concentration measurement device includes a light irradiation unit that performs intensity modulation where two lights of wavelengths different from each other are intensity-modulated by signals of a same frequency and a same phase, and a measurement object is irradiated, a detecting unit that detects a photoacoustic wave generated within the measurement object due to irradiation by the light irradiation unit, and converts the detected photoacoustic wave into a first electric signal, and a processing unit that obtains a concentration of a target component contained in the measurement object, on the basis of an amplitude and a phase of the first electric signal. Light absorption coefficients of the two lights, corresponding to a background component contained in the measurement object, are equal in change amount with regard to change in temperature, and have signs different from each other.

Component-concentration measuring apparatus and method

There is provided a respiration estimation apparatus. The respiration estimation apparatus includes an R-wave amplitude detection unit () configured to detect an amplitude of an R wave from a cardiac potential waveform of a subject, an R-R interval detection unit () configured to detect an R-R interval as an interval between an R wave and an immediately preceding R wave from the cardiac potential waveform, an acceleration displacement detection unit () configured to detect an angular displacement of an acceleration vector from a triaxial acceleration signal by a respiratory motion of the subject, a Fourier transform unit () configured to Fourier-transform each of time-series signals of the R-wave amplitude, the R-R interval, and the angular displacement to obtain a frequency spectrum of each of the signals of the R-wave amplitude, the R-R interval, and the angular displacement, and a signal selection unit () configured to extract a frequency as a candidate of a respiration frequency of the subject from each of the frequency spectrum of the R-wave amplitude, the frequency spectrum of the R-R interval, and the frequency spectrum of the angular displacement, and select best data from the frequencies as the respiration frequency of the subject.

Respiration estimation method and apparatus

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.

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Tokyo, Japan

Takuro Tajima