| 摘要 |
<p>PURPOSE:To enable high-precise measuring of a low-concentration component and the use of a low-precise device, by regulatig and fixing a device so that signals from two photo detectors are equalized to each other with a given precision. CONSTITUTION:Through flowing of zero gas to a cell 21, a gain control circuit 27 is regulated and fixed so that outputs of photo detectors 23 and 24 are equalized to each other with a given precision. With this, a signal from a differential amplifier 28 is integrated by a signal processing circuit means 29 from a point of time when an integrtor 20 starts to integrate to a point of time an integrated value attains a given value and a coincidence signal is generated, and the value is stored. Sample gas is then flowed to the cell 21, and the signal from the differential amplifier is integrated in a similar manner by the processing means 29 by means of a gain fixed by the control circuit 27. Using the two integrated values, an analysis is then made on a component to be measured. This permits the high-precise analysis of a low-concentration component and enables use of a low-precise device with the signal processing circuit means.</p> |
