This paper theoretically studied the technology of slowing light speed down based on fiber double-loop coupled resonator, which mainly carried out through numerical simulation about the loop loss influence on characteristics of slow light by using iterative and parameter matrix method.

A micro-displacement sensing scheme using the loop2 loss and a micro-bending loss modulator is proposed and realized for the first time. In order to implement micro-displacement sensing, a single-mode fiber micro-bending loss modulator was induced into loop2 to produce controllable loss. The slow light delay of 32.0668 ns was achieved in the system.

Finally, the experimental results shows that a 10 μm displacement resolution of slow light micro-displacement sensing in the displacement measuring range of 0–350 μm can be obtained.