Document Type : Research Paper


1 Electrical Engineering Dept., University of Technology-Iraq, Alsina’a street,10066 Baghdad, Iraq.

2 Ministry of Science and Technology, Materials Research Directorate, Baghdad, Iraq.


Human health is represented due to the measurement of vital signs. The basic vital signs are temperature, heart pulse rate, oxygen percentage in blood, blood pressure, etc. These signs are changes according to the physical and mental status of the individual. So measuring and monitoring those signs are very important. In this work, design and implementation of human Temperature Sensor are submitted. This is achieved using optical fiber technology. Two sensor diameters were tested; 125 µm and 60µm. The obtained results show a shifting in wavelength towards the red region due to temperature application. The submitted sensor has good sensitivity and linearity. Both sensors exhibit good responsivity, sensitivity, and high linearity. The sensitivity is increased about five times when the diameter is decreased.


  • An optical fiber temperature sensor based on MZI.         
  • Using a single-mode fiber two different diameters (125 µm, 60 µm).
  • The sensitivity was good, and the sensitivity is increased about five times when the diameter is decreased.


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