1. State Key Laboratory for Manufacturing System Engineering and Key Laboratory of Photonics Technology for Information of Shaanxi Province; School of Electronics and Information Engineering; Xi'an Jiaotong University; Xi'an 710049 P. R. China
2. The International Joint Research Center for Micro/Nano Manufacturing and Measurement Technologies; Xi'an Jiaotong University; Xi'an 710049 P. R. China
3. School of Mechanical Engineering; Xi'an Jiaotong University; Xi'an 710049 P. R. China