Abstract

For most optical tweezer applications, precise and reliable tracking of the trapped particle is an important requirement. Backfocal-plane interferometry is the fastest and most accurate tracking technique if the particle displacements are limited to half of the focal width. Especially for positive axial displacements, the nonlinear detector response can lead to incorrect tracking results. Here we show how the linear detection range around the trap center can be extended by a factor of 2 to 4 in the axial direction using a second frequency-detuned tracking focus that is generated by the same laser as the optical trap. Additionally, we show how the noise in the axial signal can be decreased significantly using a second detector.

© 2010 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Interferometric 3D tracking of several particles in a scanning laser focus

Michael Speidel, Lars Friedrich, and Alexander Rohrbach
Opt. Express 17(2) 1003-1015 (2009)

Fast parallel interferometric 3D tracking of numerous optically trapped particles and their hydrodynamic interaction

Dominic Ruh, Benjamin Tränkle, and Alexander Rohrbach
Opt. Express 19(22) 21627-21642 (2011)

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 (4)

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