Compact non-line-of-sight imager at long range

Area of Science:

• Optics and Photonics
• Computer Vision
• Remote Sensing

Background:

• Non-line-of-sight (NLOS) imaging enables detection of obscured targets, with prior work limited to short-range indoor applications.
• Practical long-range outdoor NLOS imaging faces challenges from photon loss and high background noise, especially in daylight.

Purpose of the Study:

• To develop a compact, integrated NLOS imaging prototype for effective outdoor, long-range applications.
• To overcome the limitations of existing NLOS imaging technologies in terms of range, speed, and environmental conditions.

Main Methods:

• Integration of optimized optical design, adaptive gating, high-transmittance optical devices, and fast control electronics for efficient, low-noise photon collection.
• Development of a prototype system capable of capturing and processing photonic data from non-visible target areas.

Main Results:

• Demonstration of kilometer-range NLOS imaging under daylight conditions.
• Achieved imaging rates of 2 frames per second, representing a four-order-of-magnitude improvement over previous methods.
• Successful high-efficiency and low-noise photon collection in a challenging outdoor environment.

Conclusions:

• The developed prototype significantly advances the capabilities of outdoor NLOS imaging.
• This technology provides a robust foundation for the widespread adoption of NLOS imaging in real-world scenarios.
• The system's performance in daylight and at long ranges opens new possibilities for surveillance, search and rescue, and autonomous navigation.