抄録
This article discusses the use of a difference absorption image for the gas leak detecting in the system which can only visualize leak spots of LP-gas (main ingredient: propane-gas) on real time, using two OPO-lasers, IR-camera, optical system and reflecting screen. The irradiated OPO-laser beam with a certain wavelength (3. 37μm) is fully absorbed through LP-gas, but the another with a certain wavelength (3. 23μm) is not. This absorption characteristics with respect to laser wavelength has been applied to improvement of gas detection system proposed by authors. The IR-camera consisting of InSb elements which have excellent detectivity for wavelength band of 3μm-5μm has been employed for the experiment. The experiment showed that the difference absorption procedure provides both a high detectability and remarkable capability of real time observation of leak gas images.
