Design of a novel optical vibrometer using Gaussian beam analysis

A novel optical vibration sensing method using Gaussian beam analysis is presented. In the proposed system, a Gaussian beam is emitted from a laser source with wavelength lambda = 633 nm, and incident on to a fixed quad-cell photo-detector array, which captures the light intensity distribution. A methodology will be developed to estimate the position of the beam on the plane of photodetectors, by finding a relationship between the optical power distribution of the quadcell and the x-y spatial axis of the centroid of the beam. This will enable us to identify certain characteristics of the vibration applied, such as direction, frequency and strength. The normalized power distribution for each cell has been obtained through simulation, as the beam scans the whole plane of photodetectors, and as the beam follows the trajectory y = x while moving with a speed of 1 cm/s.