Calibration method of the laser beam based on liquid lens for 3D precise measurement

• Published in: Measurement : journal of the International Measurement Confederation 2021-06, Vol.178, p.109358, Article 109358
• Main Authors: Miao, Fengjin, Wu, Bin, Sun, Zefeng, Peng, Congcong
• Format: Article
• Language: English
• Subjects: 3-D printers; Calibration; Laser beam; Laser beams; Lasers; Lenses; Liquid lens; Measurement; Simulation
• ISSN: 0263-2241; 1873-412X
• DOI: 10.1016/j.measurement.2021.109358

•A calibration method of laser beam based on liquid lens is proposed.•The optical path analysis of liquid lens is performed with decentration and tilt.•The target is quantified as a spot with certain size to be suitable for the situation in practice.•Matlab and ZEMAX simulation are performed for verification. The laser utilizing as an auxiliary equipment plays an important role in 3D precise measurement. However, the laser spot will inevitably be divergent with the increase of measurement range. To solve the problem, a calibration method of the laser beam based on liquid lens is proposed. And decentration and tilt will happen owing to installation of the liquid lens. Moreover, the focus of the laser beam can not be measured precisely in fact. Aiming at the problems mentioned above, optical path analysis of the laser beam with liquid lens is performed. To verify the correctness of the analysis, the simulation based on MATLAB and ZEMAX is performed. The experimental results show that straightness accuracy of the laser beam is 0.088 mm. And the RMSE of linear fitting of left and right laser beams are 0.013 mm and 0.035 mm within a 5 m distance respectively. Moreover, the RMSE of the spatial points is about 0.220 mm.