Optical tweezers affected by monochromatic aberrations

During the past decades optical tweezers (OT) have been in the focus of intense research. As a result, OT are used as a widespread tool in a variety of applications. In this work we investigate the effect of optical aberrations on OT. In imaging optics aberrations result in non-ideal image properties like distortion, contrast reduction, decreased resolution etc. The origin of these imaging defects can be traced back to wavefront errors, expressed by Seidel coefficients. OT suffer from these aberrations as well. They lead e.g. to a decrease of trapping efficiencies, instable trapping potentials up to complete functional failure. Based on experimental studies and numerical simulations we investigate the effect of specific optical aberrations added to a nearly ideal trapping system. The experimental results serve as validation for numerical force simulation routine based on a geometrical optics approach. That way we are able to simulate how an OT reacts to specific optical aberrations as well as combinations of them. Changes of the axial and radial optical forces compared to an ideal system indicate which kind of aberration severely impacts the OTs performance and functionality.