| 摘要 |
PURPOSE:To provide a system in which, in a detecting system for gaseous material which decides concentration of aerosol by utilizing a light resonance absorption phenomenon, an optical path is additionally mounted as a checking application, and an optical path is switched by a light shutter. CONSTITUTION:Gas or aerosol, being a material to be measured, flows into a gas cell GC through a suction hole F, and flows out through a discharge hole O. A gas cell GC1 is located on a first optical path for connecting together laser L and a collecting element D, and is mounted together with two beam slitters BS1 and BS2 and a first light shutter S1. In case concentration of gas flowing through the gas cell GC1 becomes extremely large, light power detected by a collecting system 3 is reduced to approximately a zero value, and thereby it is not distinguished from a device being out of order. In which case, with a second light shutter S2 opened, a radiant light from the laser L is caused to advance along an optical path H2. Diluted gas having a known concentration is sealed in a gas cell GC2, and thereby a light power corresponding to a known gas is collected, thereby allowing the easy and rapid decision of the presence of a trouble on a device. |
