Intensity compensation for passive in-fibre Fabry-Perot sensors in high disturbed environments

A method for compensating intensity variations in passive in-fibre Fabry-Perot sensors is studied. To achieve passive Fabry-Perot sensors for intensity compensations, three read-out cavities are used. Two path-balanced Fabry-Perot read-out cavities are designed for two quadrature signals, and the other path-imbalanced cavity is for eliminating the effect of intensity variations via subtraction from two quadrature signals. Consequently, a compensation method proposed to eliminate intensity variations in the interferometry shows good a result in highly disturbed environments