| 摘要 |
PURPOSE:To measure pressure with high accuracy, by providing a substrate having an input/output single mode optical waveguide and a pair of pressure detecting single mode optical waveguides coupled to one end of said waveguide, a means for reflecting an optical wave of a pressure detecting optical waveguide, and a means for applying the pressure to be detected, onto one of a pair of pressure detecting optical waveguides, so that a large light quantity variation can be obtained even in case of a slight pressure variation. CONSTITUTION:An input/output single mode optical waveguide 24, a Y-shaped optical branching path 23, and a pair of parallel pressure detecting single mode optical waveguides 21, 22 connected to said Y-shaped optical branching path 23 are formed by field- diffusing a silver ion onto a glass substrate 20, and a reflection film 25 is formed by vapor-depositing Al to the side end face of the optical waveguides 21, 22 of the substrate 20. A rod 9 for applying the pressure to be detected is placed on one side 21 of a pair of optical waveguides 21, 22. Light is made incident from the optical waveguide 24. In case when no pressure is applied, no phase difference is generated between optical waves propagated by a pair of optical waveguides 21, 22, therefore, light obtained by overlapping the optical waves of both waveguides 21, 22 emitted from the optical waveguide 24 shows the maximum value. |
