| 摘要 |
<p>PURPOSE:To enable execution of highly-sensitive analysis by a method wherein a highly-reflective film is formed on the inner wall of a groove used as a gas flow passage of a sample cell, by evaporating Au, Ag, Pt, Al, an alloy thereof or the like. CONSTITUTION:A highly-reflective film 13 is provided on the inner wall of a gas flow passage 12 of a sample gas of a sample cell 11 made of silicon, by evaporating or sputtering Au, Ag, Pt, Al, an alloy thereof or the like. The film thickness of the highly-reflective film 13 is preferably within a range of 800 to 2000 angstrom. When it is below this range, the film transmits an infrared light and a high reflectance can not be obtained. The reflectance of the infrared light of the highly-reflective film 13 is made 90% or above, or 99% or above preferably, and diffused reflection of the infrared light and absorption of the light are reduced by the inner wall of the gas flow passage 12. Thereby lowering of sensitivity due to miniaturization can be prevented. It is preferable that this reflective film 13 is formed on the whole surface of the inner wall of the gas flow passage 12 except a part to be an optical path of the applied infrared light.</p> |
