Open AccessBipolar absolute differential confocal approach to higher spatial resolution
Author(s) -
Weiqian Zhao,
Jiubin Tan,
Lirong Qiu
Publication year - 2004
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/opex.12.005013
Subject(s) - optics , confocal , numerical aperture , confocal microscopy , image resolution , materials science , resolution (logic) , microscopy , scanning confocal electron microscopy , differential (mechanical device) , physics , computer science , wavelength , artificial intelligence , thermodynamics
By use of a superresolution pupil filtering technique to achieve a lateral optical superresolution and a differential confocal microscopy technique to achieve an axial resolution at the nanometer level, we propose a high spatial resolution bipolar absolute differential confocal approach for the ultraprecision measurement of three-dimensional microstructures. The feasibility of the proposed approach has been proved by use of a shaped annular beam differential confocal microscopy system. The experimental results indicate that the lateral and axial resolutions of the shaped annular beam differential confocal system are better than 0.2 mum and 2 nm, respectively, when lambda=632.8 nm, epsilon=0.5, uM=6.95, and with a 0.85 numerical aperture.