Pushing the limits
of lensless imaging.
(September 22, 2015) At
the Frontiers in Optics conference researchers will describe a custom-built
ultrafast laser that could help image everything from semiconductor chips to
cells in real time.
Using ultrafast beams of extreme ultraviolet light streaming
at a 100,000 times a second, researchers from the Friedrich Schiller University
Jena, Germany, have pushed the boundaries of a well-established imaging
technique. Not only did they make the highest resolution images ever achieved
with this method at a given wavelength, they also created images fast enough to
be used in real time. Their new approach could be used to study everything from
semiconductor chips to cancer cells.
The team will present their work at the Frontiers in Optics,
The Optical Society’s annual meeting and conference in San Jose, California,
USA, on 22 October 2015.
The researchers’ wanted to improve on a lensless imaging
technique called coherent diffraction imaging, which has been around since the
1980s. To take a picture with this method, scientists fire an X-ray or extreme
ultraviolet laser at a target. The light scatters off, and some of those
photons interfere with one another and find their way onto a detector, creating
a diffraction pattern. By analyzing that pattern, a computer then reconstructs
the path those photons must have taken, which generates an image of the target
material — all without the lens that's required in conventional microscopy.
"The computer does the imaging part — forget about the
lens," explained Michael Zürch, Friedrich Schiller University Jena,
Germany and lead researcher. "The computer emulates the lens."