Abstract

Wavefront shaping with liquid-crystal spatial light modulators (LC-SLMs) is frequently hindered by a remaining fraction of undiffracted light, the so-called “zero-order.” This contribution is all the more detrimental in configurations for which the LC-SLM is Fourier conjugated to a sample by a lens, because in these cases this undiffracted light produces a diffraction-limited spot at the image focal plane. In this Letter we propose to minimize two-photon (2P) excitation of the sample, resulting from this unmodulated light, by introducing optical aberrations to the excitation beam. Aberrations are subsequently compensated by the LC-SLM, but only for the modulated part of the beam, and not for the zero-order component. In order to experimentally demonstrate the method, we use astigmatism as the optical aberration, by simply adding one or two cylindrical lenses in the optical path of the beam. A 104 decrease in zero-order-induced 2P fluorescence intensity is demonstrated. Combining this approach with temporal focusing is shown to decrease zero-order fluorescence by a factor of 4·106.

© 2014 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
LCoS nematic SLM characterization and modeling for diffraction efficiency optimization, zero and ghost orders suppression

Emiliano Ronzitti, Marc Guillon, Vincent de Sars, and Valentina Emiliani
Opt. Express 20(16) 17843-17855 (2012)

Holographic projection of arbitrary light patterns with a suppressed zero-order beam

Darwin Palima and Vincent Ricardo Daria
Appl. Opt. 46(20) 4197-4201 (2007)

Broadband suppression of the zero diffraction order of an SLM using its extended phase modulation range

Alexander Jesacher, Stefan Bernet, and Monika Ritsch-Marte
Opt. Express 22(14) 17590-17599 (2014)

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 (4)

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

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