The Phase Sensitivity of an Infinite Length Optical Fiber Subjected to a Forcing Function at a Definite Frequency and Wavenumber.
Abstract
The model developed in this report provides an exact solution to the equations of motion for an infinite length, axisymmetric, isotropic, forced cylindrical rod. The resulting mechanical stresses are inserted into the governing equations of optical phase sensitivity and the change of refractive index for an optical fiber. This approach produces a closed-form model of light propagation in the fiber when the fiber is subjected to external forcing functions at a definite wavenumber and frequency. The closed-form solution is then compared to a finite element solution and to experimental data. It is shown that the optical phase sensitivity of an infinite length fiber is shear stress dominated. When the fiber is subjected to normal pressure, the frequency domain dynamics are extremely small. However, when the fiber is subjected to shear stress, a 20-dB drop in optical phase sensitivity results between 50 and 500 Hz. A low-wavenumber approximation of the model is included, and simulations show its accuracy to a wavenumber of at least 4000 rad/m at 50 Hz.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 03, 1995
- Accession Number
- ADA294651
Entities
People
- Andrew John Hull
Organizations
- Naval Undersea Warfare Center