| 摘要 |
PURPOSE:To make possible remote measurement of temperatures in an environment full of electrical noise by detecting changes in spectral transmittance or spectral reflectance due to temperature change in material. CONSTITUTION:Light having wavelengths of 1.25 and 1.5mum from semiconductor lasers 11, 12 is fed to an optical fiber 4 through an optical synthesizing element 2 and a 3dB optical coupling element 3. The light becomes parallel one magnified by a rod lens 51, transmitted through a wafer 52 having In0.75Ga0.25As0.55P0.45 layers laminated on an InP substrate and reflected by a reflecting mirror 53 to be emitted to an optical fiber 4. The light enters the optical coupling element 3 and approximately one half of the light is reflected and fed to an optical divider 6. The latter is separated into light each having wavelengths of 1.25 and 1.5mum, thereby being inputted to optical diodes 71, 72. The output is inputted to an arithmetic processing part 8 and is subjected to division and nonlinear compensation processing to be outputted as a temperature signal. Through this process, temperature is measured remotely in the environment full of electric noise. |
