High-resolution multi-spectral snapshot 3D imaging with a SPAD array camera.

Area of Science:

• Optics and Photonics
• 3D Imaging Technologies
• Sensor Development

Background:

• Conventional light detection and ranging (LiDAR) systems rely on mechanical scanners, leading to larger system sizes, assembly challenges, and reduced lifespan due to wear.
• Existing LiDAR technologies often struggle to achieve both high resolution and multi-spectral capabilities simultaneously in a single acquisition.

Purpose of the Study:

• To develop a high-resolution, scan-less multi-spectral 3D imaging system.
• To overcome the limitations of mechanical scanners in LiDAR systems, such as size, complexity, and durability.
• To enable single-snapshot multi-spectral 3D data acquisition.

Main Methods:

• Implementation of a specially designed multiple field-of-view (multi-FOV) system.
• Separation of four-wavelength echoes carrying depth and spectral reflectance information using predetermined temporal intervals.
• Utilizing a single-pixel subarray detector (SPAD array) to sample multiple adjacent positions with subpixel offset.
• Mapping spatial positions and reflectivity to different wavelengths and time-bins.

Main Results:

• Achieved high-resolution multi-spectral 3D imaging in a single exposure.
• Demonstrated a four-times increase in pixel resolution compared to conventional methods.
• Successfully captured both depth and spectral reflectance information without a scanning component.
• The system effectively mapped positions and reflectivity to wavelengths in different time-bins.

Conclusions:

• The proposed scan-less system offers a significant advancement in 3D imaging technology.
• This novel approach enables high-resolution, multi-spectral 3D imaging in a single snapshot, eliminating the need for mechanical scanners.
• This represents the first realization of scan-less, single-exposure, high-resolution, and multi-spectral imaging using a SPAD array sensor.