| 摘要 |
PROBLEM TO BE SOLVED: To inexpensively exchange gas-correlated filters when a gas to be measured is changed. SOLUTION: In a gas-correlated filter 26, a cell 32 for a gas to be measured and an inert cell 34 are inserted into cell attaching holes of the discoid main body 30 of the filter 26 and the cell 34 is integrally fixed to the main body, but the cell 32 is attached in a detachable state with two set screws 36 and 36. A rotating shaft 44 is fixedly attached to the center of the main body 30 and, when the shaft 44 is rotated by means of a motor, the cells 32 and 34 are positioned at the optical path of infrared rays in a switchable way. |
