Dense Dispersed Structured Light for Hyperspectral 3D Imaging of Dynamic Scenes

TL;DR

This paper introduces Dense Dispersed Structured Light (DDSL), a cost-effective hyperspectral 3D imaging technique capable of capturing dynamic scenes with high spectral and depth accuracy at real-time frame rates.

Contribution

It presents a novel spectrally multiplexed pattern design and a reconstruction method enabling fast, accurate hyperspectral 3D imaging of moving scenes using affordable hardware.

Findings

Achieves 15.5 nm spectral resolution (FWHM)

Depth error of 4 mm

Frame rate of 6.6 fps

Abstract

Hyperspectral 3D imaging captures both depth maps and hyperspectral images, enabling comprehensive geometric and material analysis. Recent methods achieve high spectral and depth accuracy; however, they require long acquisition times often over several minutes or rely on large, expensive systems, restricting their use to static scenes. We present Dense Dispersed Structured Light (DDSL), an accurate hyperspectral 3D imaging method for dynamic scenes that utilizes stereo RGB cameras and an RGB projector equipped with an affordable diffraction grating film. We design spectrally multiplexed DDSL patterns that significantly reduce the number of required projector patterns, thereby accelerating acquisition speed. Additionally, we formulate an image formation model and a reconstruction method to estimate a hyperspectral image and depth map from captured stereo images. As the first practical and accurate hyperspectral 3D imaging method for dynamic scenes, we experimentally demonstrate that DDSL achieves a spectral resolution of 15.5 nm full width at half maximum (FWHM), a depth error of 4 mm, and a frame rate of 6.6 fps.