| 摘要 |
PURPOSE:To accurately measure the concentration of a sample even when the concentration is high. CONSTITUTION:The concentration and light absorption factor of a sample are found by irradiating the sample with a laser beam from an incoming port 2a (or optical fiber) after setting the sample in a casing 1 through a sample inlet 1a and generating pressure waves from the irradiated part of the sample by thermal expansion and, on the other hand, detecting the pressure waves propagated towards the periphery of the sample in the casing 1 with a pressure sensor 3 and fetching the detected signals by the sensor 3. When the concentration of the sample to be measured becomes higher, the incoming port 2a and an outgoing port 2b (or optical fibers) are brought nearer to the center of the sensor 3 to adjust the pressure received by the sensor 3 so that the pressure cannot drop even when the concentration becomes higher. Namely, the concentration of the sample is highly accurately measured even when the concentration is high by reducing the distance from the port 2a (or optical fiber) to the center of the sensor 3 so that the laser light can be sent to the front face of the sensor 3 at the time of irradiating the sample with the laser beam. |
