A novel integrated fiber-optic interferometer model and its application in micro-displacement measurement

• We proposed the structure model of integrated fiber-optic interferometer.
• We established the input-output mathematical model for micro-displacement measurement.
• We established the hardware system of the integrated fiber-optic interferometer.
• We analyzed the fitting result of experimental data of micro-displacement measurement.

We conducted an investigation in a novel integrated fiber-optic interferometer model based on ultra-small self-focusing optical fiber probe and the method of its application in micro-displacement measurement. Firstly, we proposed the structure model of integrated fiber-optic interferometer and established its input–output mathematical model applied in micro-displacement measurement. Secondly, we established the hardware system of the integrated fiber-optic interferometer. Finally, we analyzed the fitting result of experimental data of micro-displacement measurement and some error factors and defined the linear working range. The experimental results indicate that, under the given experimental conditions, the linear measurement range, linearity and sensitivity of the integrated fiber-optic interferometer were 10 μm, 1.36% and 8.8 mv/μm respectively.