| 摘要 |
PURPOSE:To prevent the occurrence of an error due to an unexpected loss in a transmission system, by a method wherein first and second lights, being different in wavelength, are radiated to a clear dielectric sensor, and a ratio between the modulated light outputs of the lights is found by the clear dielectric sensor to measure temperature. CONSTITUTION:Lights, emitted from emitters 3 and 4 which emit lights having distinct wavelengths lambda1 and lambda2, are caused to enter a clear dielectric sensor 1 through half-mirrors 5 and 6 and further through a light transfer device 7. The lights having the wavelengths lambda1 and lambda2, modulated due to temperature by a dielectric sensor 1, are sent to filters 11 and 12 from a light transfer device 8 through half-mirrors 9 and 10 to separate the light of the wavelength lambda1 from the light of the wavelength lambda2, and the separated lights are applied to their respective detectors 13 and 14. The outputs of the detectors 13 and 14 are applied to a computing circuit 15, and a ratio of a light signal, having the wavelength lambda1, to a light signal, havig the wavelength lambda2, is found to measure a temperature of a temperature measuring atmosphere 2. |
