Fast optical sampling by electronic repetition-rate tuning using a single mode-locked laser diode.

Area of Science:

• Photonics and optical engineering
• Semiconductor laser technology
• Interferometry

Background:

• Traditional optical sampling methods often require complex setups with moving parts.
• Achieving fast scan rates and customizable scan ranges simultaneously presents a significant challenge in optical metrology.

Purpose of the Study:

• To introduce and demonstrate a novel single-laser optical sampling technique called OSBERT.
• To showcase the capability of OSBERT for fast and precise distance measurements.

Main Methods:

• Utilizing electronic modulation of the repetition rate of a passively mode-locked laser diode via reverse bias.
• Implementing a highly imbalanced interferometer to generate controlled pump-probe pulse delays.
• Applying the OSBERT technique to a distance measurement task.

Main Results:

• Achieved a real-time scan rate of 1 kHz for optical sampling.
• Demonstrated precise distance measurement over a 13.0 mm range with a standard deviation of approximately 0.1 mm.
• Validated the technique from an equivalent free-space distance of 36 m.

Conclusions:

• OSBERT offers a no-moving-parts solution for optical sampling with tunable scan ranges and high scan rates.
• The technique is suitable for deployment in compact, low-cost optical sampling systems.
• Potential applications include metrology, biomedical microscopy, and sensing.