Validating data analysis of broadband laser ranging

Area of Science:

• Optical Engineering
• Metrology
• Signal Processing

Background:

• Broadband laser ranging requires precise spectral analysis.
• Dispersive Fourier transform (DFT) is crucial for high-repetition-rate measurements.
• Standard telecommunications fiber introduces higher-order dispersion, complicating DFT.

Purpose of the Study:

• To develop and validate an analysis process for laser ranging data affected by imperfect DFT.
• To enable high-precision position measurements using readily available fiber optics.

Main Methods:

• Combining spectral interferometry with DFT using standard telecommunications fiber.
• Developing a detailed analysis process to interpret ranging signals with dispersion imperfections.
• Experimental validation of the analysis process over a 27-cm scan.

Main Results:

• The developed analysis process effectively interprets ranging data from imperfect DFT.
• Experimental validation demonstrated a measurement accuracy of 50 μm.
• Achieved a root-mean-square precision of 4.7 μm for static position measurements.

Conclusions:

• The analysis method successfully compensates for higher-order dispersion in DFT-based laser ranging.
• This approach allows for accurate and precise surface position measurements using standard fiber optics.
• The validated technique offers a practical solution for high-repetition-rate metrology.