STUDY THE EFFECTIVENESS OF LONGITUDINAL STRESS ON CASCADEOPTICAL FIBER SENSOR

Abstract

 In this work, the transmission wavelength, the full width at half maximum (FWHM), and the
transmission power were studied of compressed and stretched of the intermediate No Core Fiber (NCF) of
the Single mode – No core –Single mode fiber (SNS) structure. The transmission studied when the external
medium change . The structure simulated numerically by using COMSOL multiphysics 5.5 beam envelope
method.
The focus is on understanding how the fiber diameter (NCF) influences the fiber's modal structure and its
ability to resolve wavelength shifts, especially at the standard wavelength of 1550 nm. By modeling and
simulating the fiber’s response to changes in diameter and external medium, we explore the trade-offs
between sensitivity to external RI changes and wavelength resolution. Results indicate that larger fiber
diameters enhance resolution with narrower FWHM, while smaller diameters exhibit greater tunability and
higher sensitivity to changes in the surrounding medium. The self-image length increases with diameter,
providing a longer propagation distance for light. This research offers valuable insights into optimizing
optical fiber sensors, balancing the need for resolution and sensitivity depending on the application, such
as telecommunications and environmental sensing.