Linear-Structured-Light Measurement System Based on Scheimpflug Camera Thick-Lens Imaging

• Published in: Sensors (Basel, Switzerland) Vol. 24; no. 16; p. 5124
• Main Authors: Guo, Dongyu, Cui, Jiwen, Wu, Yuhang
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 07.08.2024; MDPI
• Subjects: Accuracy; Aperture; Calibration; Cameras; Lasers; Light; measurement field; measurement model; Scheimpflug camera; sensor; structured light; measurement model; measurement field; sensor; Scheimpflug camera; structured light
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s24165124

A thick-lens, structured-light measurement model is introduced to overcome the oversights in traditional models, which often disregard the impact of lens thickness. This oversight can lead to inaccuracies in Scheimpflug camera calculations, causing systematic errors and diminished measurement precision. By geometrical optics, the model treats the camera as a thick lens, factoring in the locations of its principal points and the spatial shifts due to image plane tilting. The model deduces the positional relationship of the thick lens with a tilted optical axis and establishes a linear-structured-light measurement model. Simulations confirm that the model can precisely calculate the 3D coordinates of subjects from image light strip data, markedly reducing systematic errors across the measurement spectrum. Moreover, experimental results suggest that the refined sensor model offers enhanced accuracy and lower standard deviation.