Long-range time-of-flight scanning sensor based on high-speed time-correlated single-photon counting

Area of Science:

• Optics and Photonics
• Laser Technology
• 3D Imaging Systems

Background:

• Traditional 3D imaging systems face limitations in range and resolution for noncooperative targets.
• Scanning time-of-flight (ToF) systems offer potential for remote depth mapping.
• Single-photon counting techniques enhance sensitivity and precision in ToF measurements.

Purpose of the Study:

• To develop and demonstrate a scanning time-of-flight system for high-resolution 3D depth imaging.
• To evaluate the system's performance with distant, noncooperative surfaces under daylight conditions.
• To assess the feasibility of using low-power pulsed laser illumination for effective 3D scene acquisition.

Main Methods:

• Utilized a scanning optical system coupled with an individual single-photon detector.
• Employed the time-correlated single-photon counting (TCSPC) technique.
• Illuminated targets with a pulsed laser source operating at kHz to MHz repetition rates.

Main Results:

• Successfully acquired 3D depth images with centimeter xyz resolution.
• Demonstrated effective performance at distances up to 325 meters.
• Achieved results using low average optical power (less than 50 microwatts) in daylight conditions.
• Acquired data from low-signature targets in field trials.

Conclusions:

• The developed scanning ToF system provides a viable method for high-resolution 3D depth imaging of remote, noncooperative surfaces.
• The system's capability to operate under daylight conditions with low illumination power is a significant advancement.
• TCSPC-based scanning ToF is effective for challenging target environments and long-distance measurements.