| 摘要 |
PURPOSE:To detect the leakage of explosive or other dangerous gases by providing light emitting elements for radiating IR light and visible light together with a photodetector in the low temp. part of an electron cooling element and connecting a light reflection means for introducing the above-mentioned two beams of light to said photodetector into one body. CONSTITUTION:The laser light radiated from a laser element 2 through a light transmission window 10 in an arrow (a) direction is emitted roughly in parallel with the visible light from the element 25 and is reflected by a retroreflector 31 supported by a supporting member 30 provided at the distance l from the window 10. The reflected laser light returns in roughly parallel with the visible light to an arrow (b) direction and is photoelectrically converted by a photodetector 3. The electric signal is introduced into a signal processing unit 17. If dangerous gases G exists in the form of crossing the optical path shown by the arrows (a), (b), the IR rays are ought to be absorbed at the different wavelengths respectively specific to these gases; therefore, the gases can be discriminated by the operation of a signal processing unit 17. The leakage of extremely dangerous gases such as explosive gases and toxic gases are discovered early and disastrous accidents are prevented. |
