فهرست نشریات علمی دسترسی آزاد ایران

Abstract : Accurate measurement of vibration and acceleration is one of the fundamental requirements in various industries including civil engineering, telecommunications, medicine, and military systems. In this research, the design and simulation of an integrated optical accelerometer based on Bragg grating was performed with the aim of achieving high sensitivity, compact dimensions, and wide frequency range. The proposed structure consists of a multilayer optical waveguide containing 200 periods of Bragg grating with a central wavelength of 1 micrometer, placed on a suspended mechanical structure. Numerical simulation using the finite element method was performed with COMSOL Multiphysics software in both time and frequency domains. Results showed that the Bragg grating stopband is located at a frequency of 305 terahertz with a bandwidth of 6.5 terahertz and maximum reflectance of 99.6 percent, showing good agreement with theoretical calculations with an error of less than 5 percent. The proposed structure provides an optical sensitivity of 780 pm/g, which represents a significant improvement compared to previous works with sensitivities of 250 to 680 pm/g. The total system dimensions were reduced to 1×0.1×0.01 cubic millimeters, and a linear measurement range of ±10g with linearity better than 99 percent, resolution of 1.3 milli-g, and dynamic range of 117 decibels were achieved. The resonant frequency of 2.53 kilohertz guarantees a useful frequency range up to 300 hertz. These results demonstrate that the proposed design, in addition to higher sensitivity, possesses on-chip integration capability and mass production possibility.