| 摘要 |
PURPOSE:To provide a distribution-type gas detector which is compact, cheap and excels in response and reliability, by combining an infrared ray reflecting plate with a detector body comprising an infrared ray source and a prescribed infrared ray detection unit. CONSTITUTION:A distribution-type gas detector is composed of a reflecting plate 4' and a detector body comprising an infrared ray source 2' and an infrared ray detecting unit 3' which are juxtaposed with each other. An infrared beam is irradiated from a light source 1 upon a watched space and reflected by the plate 4' so that the beam enters into a vessel 6 through a window 5b and is divided into two optical paths by a half mirror 13a. Straightly proceeding light flux is conducted to an interference filter 15a through which only light of wavelength absorbed by detected gas passes. Light flux reflected by another mirror 14a is conducted to another interference filter 15b through which only light of wavelength adjacent to the former wavelength passes. The light having passed through these filters is introduced into an infrared ray detection unit 2 through a chopper 11 to detect the output difference between both the wavelengths to detect the gas. |
