TEMPERATURE SENSOR AND MANUFACTURE THEREOF

PURPOSE:To maintain a stable accuracy for a long time, by a method wherein a compound semiconductor and a reflection film are formed and applied to be inserted into a protective pipe and the compound semiconductor is held close to the inner surface of a sealed section of the protective pipe. CONSTITUTION:An optical fiber 1, in which a compound semiconductor 13 varying in the absorption end wavelength of light transmitting depending on temperature and a reflection film 16 for reflecting light transmitted through the semiconductor 13 are formed and applied at one end face thereof sequentially, is inserted into a protective pipe 10. Holding means 8 and 9 are provided to hold the semiconductor 13 in proximity to the inner surface of a sealed part. Then, temperature is measured from intensity of a wave of a signal light incident into a light receiving section as subjected to modulation with the semiconductor 13. No positional deviation occurs in the fiber 1, the semiconductor 13 and the reflection film 16 otherwise caused by changes in the temperature of an object to be measured, thereby maintaining a stable accuracy for a long time.