Analysis of intensity noise in a dual-comb linear optical sampling ranging system

Area of Science:

• Optics and Photonics
• Metrology
• Precision Engineering

Background:

• Dual-comb ranging (DCR) is a key absolute distance measurement technique.
• Practical DCR systems face precision limitations due to intensity noise.
• Understanding noise sources is crucial for enhancing DCR performance.

Purpose of the Study:

• To develop a comprehensive theoretical model for intensity noise in linear optical sampling DCR systems.
• To investigate the impact of hardware and algorithm parameters on ranging precision.
• To propose methods for mitigating noise and improving DCR accuracy.

Main Methods:

• Established a two-part theoretical model analyzing hardware and algorithm parameter influences on signal-to-noise ratio (SNR) and ranging precision.
• Designed and conducted experiments to validate the theoretical model.
• Developed a scheme to address photodiode detector saturation.

Main Results:

• Validated the theoretical noise model through experimental comparison.
• Achieved a ranging precision of 0.12 µm at a 2 ms refresh rate by mitigating detector saturation.
• Proposed novel evaluation criteria for assessing DCR system noise performance.

Conclusions:

• The developed theoretical model accurately describes intensity noise effects in DCR systems.
• Mitigation of photodiode detector saturation significantly enhances ranging precision.
• The study provides foundational insights for designing advanced DCR systems with improved noise immunity and accuracy.