Time-stretch multispectral LiDAR enabled by a supercontinuum laser and a single-point detector

Multispectral LiDAR enables the acquisition of both spatial and spectrally rich information from a target, and has potential in diverse target detection applications. However, it currently faces several limitations, including a limited number of spectral channels, complex optical beam-splitting architectures, and the slow response of array detectors. In this study, we propose a time-stretched multispectral LiDAR system that utilizes the broad bandwidth of a supercontinuum source to increase the number of spectral channels and applies time-stretch technology to temporally expand narrow optical pulses. Therefore, spectral and 3D spatial information can be acquired using only a single high-speed point detector, effectively eliminating the inherent structural complexity of conventional multispectral LiDAR architectures. Experimental results confirm successful spectral calibration over the 1535-1565 nm range and yield 121 discrete spectral sampling points. Additionally, polarization modulation is employed to evaluate the system's spectral dynamic range. The system is validated through experiments with representative targets, enabling simultaneous acquisition of spectral and 3D imaging data. This study presents a pathway for high-resolution spectral sensing integrated with 3D imaging.