| 摘要 |
PURPOSE:To enable high precision detection of a distribution status of observation gas by installing a scan mirror scanning an observation region at an elevated place and slantly irradiating an infrared ray from a laser beam source to a ground surface. CONSTITUTION:An infrared ray from a carbon oxide gas laser beam source 11 becomes a parallel beam by means of a transmitter mirror 12 and is branched out at a right angle by means of a beam splitter 13. Then it is irradiated obliquely to the ground surface by means of a scan mirror 14 installed at an elevated place. A reflective light from a ground surfacc 15 is detected by an infrared ray detector 17 after passing through a prearranged channel, and is converted to an electric signal. Under this constitution, the existence position and distribution state of gas are detected, because a dispersed light between r1 and r2 where the objective gas to be observed is unusually reduced. As a result, the intensity of a dispersed light coming back, reflecting on a ground surface is more significant, compared to one irradiated in a space region. Thus it is possible to correctly grasp a gap distribution state and get along with a low output light source. |
