Fast-scanning speed single-photon counting LiDAR based on front focal length modulation.

Area of Science:

• Optics and Photonics
• Remote Sensing Technology
• Laser Systems Engineering

Background:

• Long-range LiDAR systems face challenges with scanning speed at close ranges due to laser divergence.
• The laser divergence angle is influenced by the distance from the transmitter lens to the beam waist, as described by the thin lens equation for Gaussian beams.
• Scanning speed in LiDAR is directly correlated with the laser divergence angle.

Purpose of the Study:

• To present a method for enhancing LiDAR scanning speed at close ranges.
• To compensate for the effects of laser divergence angle on scanning speed in long-range LiDAR.
• To improve the operational efficiency of LiDAR systems in near-field applications.

Main Methods:

• Implementation of front focal length modulation within the LiDAR transmitter.
• Utilizing the thin lens equation for Gaussian beams to analyze laser divergence.
• Modulating the laser divergence angle by adjusting the front focal length of the transmitter lens.
• Experimental validation of the proposed method.

Main Results:

• The proposed method successfully increases LiDAR scanning speed at close ranges.
• Front focal length modulation effectively compensates for laser divergence effects.
• Target detection performance is maintained while enhancing scanning speed.
• Experimental analysis confirms the efficacy of laser dispersion angle modulation.

Conclusions:

• Front focal length modulation is a viable technique for fast-scanning LiDAR.
• The method improves scanning speed in close-range detection scenarios for long-range LiDAR.
• This advancement ensures target detection performance is not compromised by increased speed.