چكيده به لاتين
With advances in fiber optics and fiber optic sensors in recent years and because of the advantages of these sensors, including precision, short response time and immunity to electromagnetic interference, their use is expanding. Fiber optic sensors can be used to detect gas, liquid, pressure, temperature, etc, that could be employed in various applications such as petrochemicals, food and water quality control industries. The fabrication of these sensors is carried out by depositing a sensitive layer on the fiber surface. The sensing mechanism is based on the physical and chemical changes occurring in the adsorbent layer and its effect on the light passing through the fiber.
The fiber optic sensors have various types. Among these sensors, the tapered fiber sensors have attracted much attentions due to their high speed performance, high sensitivity and low cost.
In this thesis, the fiber optic sensor are introduced and their mechanism of operation is explained. Then, the hydrogen gas sensor is described using a tapered fiber and its operation is described. Finally, the test layout, the equipment used and the result are presented.
The sensors made in this test depend on the diameter and tapered angle have different sensitivities, the best sensitivity of the spectrum to the tapered fiber with a diameter of and a tapered angle of degrees equal with a response time of seconds and a return time of seconds Obtained.
