Advancing the Boundaries: New Approaches in Modern Optical Microscopy

The webinar presents recent research activities in the field of microscopy conducted at the Bremer Institut für angewandte Strahltechnik (BIAS). The focus will be on two approaches which open up new possibilities for high-resolution and application-specific imaging.

Lensless microscopy enables very compact and low weight optical setups, making it particularly attractive for integration into production lines or space-constrained systems. Furthermore, the image reconstruction process is inherently aberration-free, allowing for significantly larger amounts of data per image compared to conventional lens-based systems. In addition, the approach is not affected by chromatic dispersion, enabling advanced techniques such as white-light interferometry to be implemented without traditional imaging optics.

Near-field assisted microscopy uses refractive microstructures. These structures are fabricated via 3D laser lithography based on two-photon polymerization that allows for complex geometries. The aim is to couple near-field evanescent waves into propagating modes, thus enabling imaging beyond the Abbe resolution limit. The flexibility of the 3D fabrication process also enables the correction of image aberrations by tailoring the geometry of the refractive element.

The webinar provides an introduction to both cutting-edge approaches and presents experimental results that highlight their potential.

Subject Matter Level: Intermediate - Assumes basic knowledge of the topic

What You Will Learn:
• Gain insights into lensless imaging based on digital holography and near-field enhanced microscopy using custom-fabricated refractive microstructures.
• Understand the advantages of lensless optical systems and how they outperform conventional lenses.
• Explore real-world experimental results and learn how advanced fabrication and computational methods enable imaging for industrial and scientific applications.

Who Should Attend the Webinar: 
• MSc students and graduate students in the field of optics.
• Researchers and engineers interested in widening their view on novel application-oriented microscopy techniques aimed at industrial inspection.

About the Presenter: Ralf B. Bergmann from The Institute of Applied Beam Technology (BIAS)

Ralf B. Bergmann received his doctoral degree from the University of Stuttgart (UStg) in 1991 for his work at the Max Planck Institute for Solid State Research (MPI-FKF). In 1991 he joined the University of New South Wales (UNSW) in Sydney, Australia and returned to the MPI-FKF in 1993. From 1997 on, he worked at UStg, at the former Institute of Physical Electronics heading a research group on crystalline Silicon. He obtained his Habilitation in 1998 from the University of Freiburg. In 2001, he joined the Corporate Research Centre of the Robert Bosch Corp. (RB) in Stuttgart as head of the department of Applied Physics. From 2006 on, he headed the Physical Analysis Lab within the business unit of Automotive Electronics of RB in Reutlingen, Germany. In 2008, he became a Professor at the University of Bremen, Germany, and a Director at the Institute of Applied Beam Technology (BIAS). His present work is around optical metrology and optoelectronics including nano-optics and quantum sensors.