title: Interference Confocal Microscope Integrated with Spatial Phase Shifter.
abstract: We present an interference confocal microscope (ICM) with a new single-body four-step simultaneous phase-shifter device designed to obtain high immunity to vibration. The proposed ICM combines the respective advantages of simultaneous phase shifting interferometry and bipolar differential confocal microscopy to obtain high axis resolution, large dynamic range, and reduce the sensitivity to vibration and reflectance disturbance seamlessly. A compact single body spatial phase shifter is added to capture four phase-shifted interference signals simultaneously without time delay and construct a stable and space-saving simplified interference confocal microscope system. The test result can be obtained by combining the interference phase response and the bipolar property of differential confocal microscopy without phase unwrapping. Experiments prove that the proposed microscope is capable of providing stable measurements with 1 nm of axial depth resolution for either low- or high-numerical aperture objective lenses.
authors: Institute of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin 150001, China. weibo.wang@eng.ox.ac.uk.|Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK. weibo.wang@eng.ox.ac.uk.
authors: Weibo
authors: W
authors: Wang
authors: Institute of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin 150001, China. gukang90@163.com.
authors: Kang
authors: K
authors: Gu
authors: Institute of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin 150001, China. youxiaoyudyx@163.com.
authors: Xiaoyu
authors: X
authors: You
authors: Institute of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin 150001, China. jbtan@hit.edu.cn.
authors: Jiubin
authors: J
authors: Tan
authors: Institute of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin 150001, China. liujian@hit.edu.cn.
authors: Jian
authors: J
authors: Liu
keywords: confocal microscope; interference; phase shift; spatial phase shifter