HYDROGEN DETECTING OPTICAL SENSOR

摘要

PURPOSE:To detect gaseous hydrogen by only the signal of light and to make possible the reduction in the size of a sensor and the improvement of the reliability thereof by forming an optical waveguide of a dielectric material and coating the surface thereof with a thin metallic film laminated with a material which dissociates and adsorbs the gaseous hydrogen. CONSTITUTION:The waveguide 2 is provided on a substrate 1 consisting of transparent glass, plastic, etc. and the surface thereof is coated with the thin metallic film 3. The thin film 3 consists of the material which adsorbs and reduces the gaseous hydrogen and generates electrons and protons. The waveguide 2 consists of the material of which the coefft. of light absorption changes by receiving the electrons and protons. The other end of a fiber 4A 'which is connected to one end of the waveguide 2 is connected to a light source 5 and the other end of an optical fiber 4B connected to the other end of the waveguide 2 is connected to a photodetector 6 to measure the quantity of the detected light. Then the optical waveguide 2 colors according to the concn. on the gaseous hydrogen existing at the point where the sensor is installed. The quantity of the light emitted therefrom changes accordingly and therefore the concn. of the gaseous hydrogen is known by measuring the quantity of the detected light.