3D surface reconstruction of transparent objects using structured light with PMP-LIF method

Acquiring high-quality 3D information from transparent materials, which exhibit weak light scattering and absorption characteristics, presents a formidable challenge. In this paper, we introduce a novel three-dimensional reconstruction method called PMP-LIF (Phase Measurement Profilometry with Laser-Induced Fluorescence). This approach uses machine vision and incorporates structured light technology with laser-induced fluorescence to enhance the reliability and robustness of surface profile data for transparent objects by improving their reflectivity. In our study, we accomplished a three-dimensional reconstruction of surface profiles for transparent materials by employing a structured light pattern with a 544 nm wavelength, projected using a DLP (Digital Light Processing) projector. The image data was captured using a binocular vision system. Any distorted information within the image data was processed using image processing techniques, such as a phase unwrapping algorithm. The adoption of the PMP-LIF method for image data acquisition streamlines the complexity of the image acquisition system while preserving the accuracy of surface profile information. We conducted three-dimensional reconstruction tests on various objects, including human face shapes, on the surfaces of static liquids and transparent aspheric mirror blanks. The results reveal root-mean-square errors of 0.34 mm and 1.67 mm for the registration of the reconstructed point cloud information with fitting planes, respectively.