Publications by Johann Rohner | EPFL Graph Search

Optical Mirror from Laser-Trapped Mesoscopic Particles

Trapping of mesoscopic particles by optical forces usually relies on the gradient force, whereby particles are attracted into optical wells formed by landscaping the intensity of an optical field. This is most often achieved by optical Gaussian beams, inte ...

Amer Physical Soc2014

Miniaturized optical tweezers based on high-na micro-mirrors

René Salathé, Johann Rohner, Fabrice Merenda

The invention relates to an optical tweezer device including at least one light source (2) and one three-dimensional optical trap (9,10), said optical trap comprising one focusing micro-mirror (7) which is adapted to reflect and focus at least a portion of ...

2009

Comparison between various types of multiple optical tweezers

René Salathé, Johann Rohner, Fabrice Merenda, Jean-Marc Fournier

Many types of optical tweezers arrays have been proposed and developed for use in conjunction with microfluidics for bio-chemical essays. Trap arrays rely on different methods allowing various degrees of flexibility and relative trapping efficiencies. Amon ...

Spie-Int Soc Optical Engineering2008

Statistical study of optical trapping efficiency

René Salathé, Johann Rohner, Olivier Martin, Jean-Marc Fournier, Lina Huang

2007

Micro-optics for optical trapping in microfluidics - art. no. 66440P

René Salathé, Johann Rohner, Fabrice Merenda, Jean-Marc Fournier, Elodie Lamothe

Micro-optical compo nents offer several possibilities for creating large matrices of optical traps, either when working on inverted microscopes, or by directly integrating miniaturized optical components at the level of a micro-fluidic chip. In thisarticle ...

2007

Refractive multiple optical tweezers for parallel biochemical analysis in micro-fluidics

René Salathé, Horst Vogel, Johann Rohner, Fabrice Merenda, Jean-Marc Fournier

We present a multiple laser tweezers system based on refractive optics. The system produces an array of 100 optical traps thanks to a refractive microlens array, whose focal plane is imaged into the focal plane of a high-NA microscope objective. This refra ...

2007

Combining multiple optical trapping with microflow manipulation for the rapid bioanalytics on microparticles in a chip

Guy Delacrétaz, René Salathé, Philippe Renaud, Johann Rohner, Fabrice Merenda, Gerben Boer

An array of four independent laser traps is combined with a polydimethylsiloxane microfluidic chip to form a very compact system allowing parallel processing of biological objects. Strong three dimensional trapping allows holding objects such as functional ...

American Institute of Physics2007

Light structuring for massively parallel optical trapping

Johann Rohner

Optical trapping, discovered in the 70's, allows moving and stabilizing small objects which sizes varies from atoms to particles of several microns. This technique, based on momentum conservation, is particularly well suited for manipulating biological mat ...

EPFL2007

Multiple optical trapping in high gradient interference fringes

René Salathé, Johann Rohner, Fabrice Merenda, Jean-Marc Fournier

In biological investigations, many protocols using optical trapping call for the possibility to trap a large number of particles simultaneously. Interference fringes provide a solution for massively parallel micro-manipulation of mesoscopic objects. Concur ...

2006

Escape trajectories of single-beam optically trapped micro-particles in a transverse fluid flow

Guy Delacrétaz, René Salathé, Johann Rohner, Fabrice Merenda, Gerben Boer

Optical Society of America2006