| 摘要 |
<p>PURPOSE:To take measurements at various requests by inserting an intermediate member into plural holes of one measurement cell and setting length of a measurement light path. CONSTITUTION:The end surface of the measurement cell on the side of a light source consists of a member 28 which does not transmit infrared rays and plural holes are bored in this member 28 along the periphery of rotation of the light source 24; and intermediate members 30 (30-1, 30-2...) which transmit infrared rays are inserted into those holes and the member 30 has inert gas charged in a hollow cylinder made of, for example, an infrared-ray transmissive material. Then when sample gas is admitted into the cell 20 and the light source 24 is rotated by a motor 26, infrared rays are incident on the cell 20 intermittently from the rotating light source 14 through the holes in the light-source side end surface of the cell 20. In the cell 20, the infrared rays are absorbed to the measurement light path length L between the member 30 and a cell window 22 and transmitted infrared rays are guided to an infrared-ray detector 420 through a condenser lens 40 and detected. Thus, measurements are taken at various requests.</p> |
