Abstract

We analyze the far-field resolution of apertures that are illuminated by a point dipole located at subwavelength distances. It is well known that radiation emitted by a localized source can be considered a combination of traveling and evanescent waves, when represented by the angular spectrum method. The evanescent wave part of the source can be converted to propagating waves by diffraction at the aperture; thereby it contributes to the far-field detection. Therefore one can expect an increase in the resolution of objects. We present explicit calculations showing that the resolution at the far zone is improved by decreasing the source-aperture distance. We also utilize the resolution enhancement by the near field of a dipole to resolve two closely located apertures. The results show that without the near field (evanescent field) the apertures are not resolved, whereas with the near field of the dipole the far zone intensity distribution shows improved resolution. This method eliminates the requirements of near-field techniques such as controlling and scanning closely located tip detectors.

© 2012 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Superresolution of near-field optical microscopy defined from properties of confined electromagnetic waves

J. M. Vigoureux, F. Depasse, and C. Girard
Appl. Opt. 31(16) 3036-3045 (1992)

Graphene-based near-field optical microscopy: high-resolution imaging using reconfigurable gratings

Sandeep Inampudi, Jierong Cheng, and Hossein Mosallaei
Appl. Opt. 56(11) 3132-3141 (2017)

Subwavelength electromagnetic near-field imaging of point dipole with metamaterial nanoslab

Timo Hakkarainen, Tero Setälä, and Ari T. Friberg
J. Opt. Soc. Am. A 26(10) 2226-2234 (2009)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (3)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (7)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription