Presentation title:

Chromatic confocal measurement method and algorithms

Abstract: Chromatic confocal measurement method is an advanced non-contact optical measurement technique for 3D surface profile and thicknesses of single-layer or multi-layer media. Three kinds of dispersive lens groups with different measurement ranges are designed and assembled. A new chromatic confocal sensor with a large axial measurement range over 15 mm is built using a phase Fresnel zone plate. The axial resolution and displacement measurement accuracy are experimentally obtained by a laser interferometer. Peak extraction algorithms and calibration methods are quantitatively compared. The thicknesses of quartz glass is measured with an accuracy of 1 %. 3D measurements of filler height, MEMS, and silicon wafer have been implemented. 

Brief Bio: 

Dr. Tao Liu

Associate Professor, School of Mechanical Engineering, Xi'an Jiaotong University

He obtained a PhD of Engineering, and he is currently the senior member of Chinese Society for Measurement, Chinese Optical Society, and Chinese Society of Micro and Nano Technology.

2003.9-2007.7, Harbin Institute of Technology, Optoelectronic Information Engineering, Bachelor’s Degree

2007.9-2013.12, Harbin Institute of Technology, Instrument Science and Technology, PhD Degree ( Supervisor: Prof. Jiubin Tan, Academician)

2010.10-2011.10, Joint PhD at Oxford University (Supervisor: Prof. Tony Wilson, Academician)

2014.5-2020.5, Postdoc researcher, Xi'an Jiaotong University, Instrumentation Science and Technology (Supervisor: Professor Zhuangde Jiang, Academician)

He is mainly engaged in the research of 3D optical imaging and measurement, including confocal microscopy, white light interferometry, super-resolution optical scanning microscopy, and diffraction optics. He has published 1 book on 3D confocal microscopy for measurement, 40 academic papers, and has been granted 20 national invention patents and registered 2 software copyrights.

Personal homepage: http://gr.xjtu.edu.cn/web/liu8483