| 摘要 |
PURPOSE:To eliminate the influence of a background from only a result of measurement against a sample and to derive the concentration of an object to be analyzed by irradiating a sample simultaneously by two or more excitation light beams having each different optical wavelength and optical intensity modulation frequency. CONSTITUTION:When the inside of an acoustooptical cell 8 is filled with a liquid sample and excitation light beams 5, 6 are made incident, acoustooptical signals generated in accordance with two excitation light beams are superposed to each other, and converted as the acoustooptical wave to an electric signal 9 by a piezo-electric element. The acoustooptical signals converted to this signal 9 are allowed to branch to two signals, and inputted to a phase detecting device 10 and 11. Subsequently, in the device 10, by using a signal 12 synchronizing with the modulation of an optical intensity modulator 3 as a reference signal, only an acoustooptical signal 13 corresponding to the excitation light beam 5 is extracted from the detected signal 9, and inputted to a data processor 14. In the same manner, in the device 11, by referring to a signal 15 from an optical intensity modulator 4, only an acoustooptical signal 16 corresponding to the excitation light beam 6 is extracted and inputted to the device 14. In the device 14, based on the signals 13, 16, the analytical cure of an object to be analyzed is generated, and an unknown sample is brought to quantitative analysis. |
