-Light flammable gas concentration detecting device and light-type flammable gas concentration detection method

摘要

PROBLEM TO BE SOLVED: To provide an optical combustible gas concentration detection method which enables the measurement of the concentrations of a plurality of kinds of gases at the same time and correction of the wavelength of the absorbing ray of each of the gases to accurately detect the concentration of the gas.;SOLUTION: A liquid branching means 13 for branching a laser beam is connected across a laser 2 and a light receiver 5, and a reference light path 14 not permitting a gas atmosphere to pass, a gas detecting light path 15 permitting the gas atmosphere to pass and a gas-in-air detecting light path 15R for measuring a component gas contained in air are connected to the light branching means 13. The wavelength of 1,650-1,690 nm of the laser beam is swept and the center wavelength of the laser beam is corrected from a gas signal component being the difference between the signal obtained from the gas detecting light path 15 and the signal obtained from the reference light path 14 and a reference gas signal component being the difference between the signals obtained from the gas-in-air detecting light path 15R and the reference light path 14 to measure the concentrations of propane gas, an isobutane gas, an n-butane gas and a methane gas contained in the gas atmosphere at the same time from transmitted light.;COPYRIGHT: (C)2009,JPO&INPIT