Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


A new Concept in Microscopy

Self-reconstructing Laser Beams - published in “Nature Photonics”

It’s a familiar situation for all car drivers. In the autumn, when the roads are foggy, visibility drops below 50 metres. The light of the car’s headlights are scattered by the drops of fog, meaning we can’t see objects further away because the light can’t reach them.

This everyday example illustrates a key problem of light microscopy. When used in modern cell biology, the dense clusters of thousands of cells scatter the light so strongly that the cells located in the back of an object can hardly be seen. Although better known from science fiction, the concept of self-reconstructing laser beams offers a promising solution to the problem.

Together with his team of scientists, Dr. Alexander Rohrbach, Professor for Bio- and Nano-photonics at the University of Freiburg’s Department of Microsystems Engineering – IMTEK, is developing new, unconventional techniques in microscopy “whose physical concepts are at least as exciting as their technical realisation,” Rohrbach said. His doctoral student, Florian Fahrbach, whose research focuses on self-reconstructing laser beams, added, “We’ve been working on this for the last four years.

Without the support of the Freiburg Cluster of Excellence BIOSS – Centre for Biological Signalling Studies and Carl Zeiss MicroImaging GmbH, it would have been very difficult to realise the concept we’re now presenting!” Rohrbach is also pleased: “We managed to achieve a direct transfer from basic research to application in the form of a new microscope. That's definitely what most researchers want!”

In the forthcoming November issue of Nature Photonics the scientists describe their new light microscope, which relies on beams that reconstruct themselves in light-scattering media. The new method not only provides novel insights into the physics of complex light scattering, but it also enables, for example, to look about 50 percent deeper into human skin tissue than with conventional laser beams. The scientists have named their new invention MISERB (microscope with self-reconstructing beams).

The researchers from Freiburg were able to demonstrate in several experiments that specially formed laser beams are able to self-reconstruct even in the presence of various obstacles, for example a high number of light-scattering biological cells, which repeatedly destroy the laser beam’s profile. Self-reconstruction works because the scattered photons (light quanta) at the centre of the beam are constantly replaced by new photons from the side. What is so astounding is that the photons from the side all converge at the centre of the beam nearly in phase in order to build a new beam profile, undeterred by considerable lags from the scattering. The scientists therefore used a computer hologram (a device that changes the phase of light) to modify conventional laser beams into so-called Bessel beams whose phase profile has the shape of a cone. Although Bessel beams are known to be diffraction-free in free space, it has been completely unclear whether, and to what degree, they are able to regain their original beam shape also in inhomogeneous media, where light scattering is considerable.

Not only do the results of this study have the potential to generate more exciting physical experiments in the field of nonlinear optics, but the BIOSS Cluster of Excellence also has reason to hope that it will make new biological signal cascades deep inside living organisms more visible than ever before.

Melanie Hübner | alfa
Further information:

More articles from Studies and Analyses:

nachricht Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung

nachricht High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Oasis of life in the ice-covered central Arctic

24.10.2016 | Earth Sciences

‘Farming’ bacteria to boost growth in the oceans

24.10.2016 | Life Sciences

Light-driven atomic rotations excite magnetic waves

24.10.2016 | Physics and Astronomy

More VideoLinks >>>