An optimisation design of adaptive illumination for a multi-reflective 3D scene. (June 2017)

• Record Type: Journal Article
• Authors: Lyu, Chengang; Gao, Shuang; Yang, Jiachen
• Is Part Of: Optics and lasers in engineering. Volume 93(2017)
• Page Start: 128
• Page End: 138
• Publication Date: 2017-06
• Subjects: Adaptive illumination -- Projector-camera system -- Machine vision -- Iteration; Lasers in engineering -- Periodicals; Optical measurements -- Periodicals; Optics -- Periodicals; Lasers en ingénierie -- Périodiques; Mesures optiques -- Périodiques; Optique -- Périodiques; 621.36605
• DOI: 10.1016/j.optlaseng.2017.02.001
• Languages: English
• ISSNs: 0143-8166

Abstract

Abstract: An illumination optimisation technique applied to multi-reflective 3-D machine vision based on a projector-camera system is introduced, in which the projector plays a key role to compensate for surface reflectance at each pixel to be inversely proportional to the brightness of the pixel under ambient light. The adaptive illumination technology was achieved by iterations emphasising different illumination intensities according to different surface orientations and requiring an accurate correspondence between the projector pixels and the camera pixels. In order to establish the most effective correspondence to prepare for subsequent adaptive illumination, 4 kinds of grating patterns, including sinusoidal, rectangular, triangular, and dual-frequency sinusoidal grating patterns, were projected and compared. The iterations were halted when an optimally lit scene was obtained; the further experiments under weak and strong light searched for the best method of illumination optimisation and confirmed the reliability of the adaptive illumination. The proposed optimisation design could run in real time and became a viable solution for industry. Highlights: An illumination optimisation for multi-reflective machine vision is introduced. Four patterns are compared to establish the most effective correspondence. The adaptive illumination is achieved by iterations and reliability is confirmed. The optimisation design can run in real time and is viable for industry.