| 摘要 |
Methane gas detector based on the property of methane gas of, when irradiated with infrared light, absorbing light with wavelengths which coincide with the absorption lines of the gas. The light reflected from a gas sensor 4 is conducted to a narrow-band filter 6 corresponding to the absorption line of the gas, after which the light transmitted is detected 7 and forms a measurement value. The light which is not transmitted is reflected and is conducted to a broad-band filter 10 centred around the absorption line of the methane gas, after which the transmitted light is detected 11 and forms a reference value. A measure of the methane gas content is obtained by subtracting the measurement value from the reference value. <IMAGE> |
