Fiber self-mixing interferometer with orthogonally polarized light compensation.

A fiber heterodyne self-mixing interferometer with orthogonally polarized light compensation is achieved. This system can adapt to various complex scenes while still keeping ultra-high sensitivity and anti-disturbance capability. Ultra-high sensitivity microchip laser is used as the laser source and polarization maintaining(PM) fiber makes the light path easy to accommodate to complex spaces, such as remote or narrow and small space. Besides, orthogonally polarized light inside PM fiber can eliminate the measurement error on account of environment disturbance. At present, the displacement resolution could be less than 10nm, which shows a great potential in nano-metrology.