摘要 |
An integrated-optic waveguide apparatus uses a photoelastic substrate for sensing temperature changes. Optical channels are formed in a photoelastic crystal substrate by depositing film stripes thereon to cause stress-induced changes in the relative refractive index responsive to changes in the substrate temperature. Absorption and coupling or switching of light waves between the channels provides a variable light intensity as a function of temperature. A single-mode temperature sensor of the interferometer type provides high sensitivity without requiring a secondary reference light source. Multimode temperature sensors are also described which exhibit a wide dynamic range useful up to several hundred degrees C. at a slight compromise in sensitivity.
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