Direct characterisation of a pure evanescent focus of a high numerical aperture objective lens

Search Swinburne Research Bank

Home

Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/2382

Title: Direct characterisation of a pure evanescent focus of a high numerical aperture objective lens
Author(s): Gan, Xiaosong; Gu, Min; Jia, Baohua
Abstract: In this paper, intensity distributions of the tightly focused evanescent field generated by a centre blocked high numerical aperture (NA=1.65) objective lens are investigated by a scanning near-field optical microscope The pure focused evanescent field is mapped and a splitting phenomenon of the focal spot along the direction of polarization, caused by depolarization, is observed. The measurement result is compared with the calculation based on vectorial diffraction theory; a good match has been found. The decaying nature of the focused evanescent wave also shows a good agreement with the theoretical predication, indicating that the field is purely evanescent and does not contain significant contribution from the propagating component.
Publication type: Conference paper
Research centre: Swinburne University of Technology. Faculty of Engineering and Industrial Sciences
Source: Proceedings of the Australian Institute of Physics 16th National Congress [2005], 30 January - 4 February 2005, Canberra, Australian Capital Territory
Publication year: 2005
Publisher: Australian Institute of Physics
ISBN: 0959806482
Publisher URL: http://aipcongress2005.anu.edu.au/index.php?req=CongressProceedings
Peer reviewed