Subdiffraction-limited radius measurements of microcylinders using conventional bright-field optical microscopy

Douglas J. Little*, Deborah M. Kane

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)
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A technique for measuring the radius of dielectric microcylinders with subdiffraction-limited precision is presented. Diffraction fringes arising from the dielectric cylinder are measured using conventional bright-field optical microscopy and compared with theory to deduce the radii. The technique has been demonstrated measuring the radii of the major-ampullate silks from Plebs eburnus spiders. Precision better than 50 nm is demonstrated, using a standard optical microscope with a numerical aperture of 0.6 for the objective. Accuracy was verified using scanning electron microscopy. This technique will facilitate rapid, precise measurement of dielectric microcylinder radii, enabling a new optical-microscopy-based measurement approach for these challenging micro-optics.

Original languageEnglish
Pages (from-to)5196-5199
Number of pages4
JournalOptics Letters
Issue number17
Publication statusPublished - 1 Sept 2014

Bibliographical note

This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.


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