| 摘要 |
PURPOSE:To obtain a highly accurate, highly sensitive, highly reliable, compact gas sensor, by providing electrodes in the vicinity of a waveguide, which is branched from a single input path formed on a specified substrate and made to merge at an output path again, providing a light battery and a gas detecting part on the substrate, and connecting the parts by a current feeding path. CONSTITUTION:Ti is diffused in a substrate comprising LiNbO3 having an electrooptic effect and an input path 7 is formed. Branch paths 8 and 9 are split from the input path 7 and are made to merge into an output path 10 again. Thus a waveguide 3 is formed and a light-interference generating circuit 2 is constituted. Electrodes 6 are provided in the vicinity of the branch path 9 in the circuit 2. A light battery 4 and a gas detecting part 5 are provided on the substrate 1 and they are connected by a current feeding circuit 11. The electromotive force of the light battery 4 is supplied to the gas detecting part 5 through the current feeding path 11. Owing to the change in resistance of the gas detecting part 5, the voltage across both electrodes 6 is changed. Based on the voltage change, the power of the light inputted to a light detector 14 through the waveguide 3 from the light source 13 is changed, and gas is detected. Thus the highly accurate, highly sensitive, highly reliable, compact gas sensor is obtained. |
