| 摘要 |
<p>PURPOSE:To clean easily an inlet part of gas to be tested by closing hermetically with a detector proper provided with transparent windows at the parts other than the inlet part of the sample gas. CONSTITUTION:A sample gas inlet part 13 which is not closed hermetically is formed as a recess which is covered with transparent windows 15a, 15b and it is covered with an infrared detector proper 12 consisting of infrared light source 16, optical filters 21a, 21b for a ray of light for the sample gas penetrating wave length and for adjacent wave lengths, filter switching monitor 22, infrared light detecting element 24, reflecting mirror 18 together with the windows 15a, 15b. By forming the inlet part 13 as a recess provided with an opening, the windows 15a, 15b of the sample gas can easily be cleaned without disassembly, etc. Further, by a ratio of detected values of rays of light received introduced after passing through two kinds of filter, gas concentration can be detected and effects of background emission, etc. can be prevented.</p> |
