| 摘要 |
<P>PROBLEM TO BE SOLVED: To achieve component concentration measurement which is accurate and is not affected by a boundary state. <P>SOLUTION: A laser diode 1 emits light to an object 11 to be measured. An acoustic sensor 5 detects photoacoustic signals generated from the object 11. An information processing device 10 measures amplitude and a phase of a measurement signal while taking a signal of a reference frequency having the largest amplitude out of electric signals obtained at a first time as the measurement signal, and measures a phase of a measurement signal by taking a signal of a reference frequency after the elapse of a period of time as the measurement signal. The information processing device 10 alters the frequency of the measurement signal so that the phase after the elapse of the arbitrary period of time is equal to the phase of the first time. The information processing device 10 measures the amplitude by taking the signal of the altered frequency as a measurement signal, and derives the concentration of a component of a target to be measured after the elapse of the arbitrary period of time from the amount of the change between the measured amplitude and the amplitude measured at the first time. <P>COPYRIGHT: (C)2012,JPO&INPIT |
