All-fiber laser feedback interferometry with 300  m transmission distance

Area of Science:

• Optics and Photonics
• Metrology
• Sensor Technology

Background:

• Traditional interferometry faces challenges with long transmission distances and uncooperative targets.
• Drift and signal loss are significant issues in remote sensing applications.
• High sensitivity and simple structures are crucial for practical interferometric systems.

Purpose of the Study:

• To propose a novel laser feedback interferometry system capable of long transmission distances.
• To enhance sensitivity for uncooperative targets and simplify system structure.
• To experimentally validate the system's performance, including displacement resolution and drift compensation.

Main Methods:

• Development of a laser feedback interferometry system.
• Implementation of a quasi-common path orthogonally polarized light compensation method for drift reduction.
• Experimental testing with a copper block target at a 300 m transmission distance.
• Evaluation of displacement resolution, linearity, and power consumption.

Main Results:

• Achieved over 200 times reduction in drift using the compensation method.
• Demonstrated a displacement resolution of 20 nm at a 300 m transmission distance.
• Measured sub-microwatt power consumption for the measurement beam, indicating high sensitivity.

Conclusions:

• The proposed laser feedback interferometry system demonstrates high sensitivity and long-distance capability.
• The quasi-common path compensation method effectively mitigates drift in long-distance transmissions.
• The technology shows promise for practical applications in remote, nuclear radiative, or other harsh environments.