The world’s first
image of a fly taken with the help of an all-laser-based X-ray tomography
imaging method. It
consists of around 1500 individual images. Even extremely fine
structures appear
in three-dimensional detail. These would remain invisible
in a conventional
X-ray image. Image: Karsch/Pfeiffer
Physicists from Ludwig-Maximilians-Universität, the Max
Planck Institute of Quantum Optics and the TU München have developed a method
using laser-generated X-rays and phase-contrast X-ray tomography to produce
three-dimensional images of soft tissue structures in organisms.
(August 14, 2015) With
laser light, physicists in Munich have built a miniature X-ray source. In so
doing, the researchers from the Laboratory of Attosecond Physics of the Max
Planck Institute of Quantum Optics and the Technische Universität München (TUM)
captured three-dimensional images of ultrafine structures in the body of a
living organism for the first time with the help of laser-generated X-rays.
Using light-generated radiation combined with phase-contrast X-ray tomography,
the scientists visualized ultrafine details of a fly measuring just a few
millimeters. Until now, such radiation could only be produced in expensive ring
accelerators measuring several kilometers in diameter. By contrast, the
laser-driven system in combination with phase-contrast X-ray tomography only
requires a university laboratory to view soft tissues. The new imaging method
could make future medical applications more cost-effective and space-efficient
than is possible with today’s technologies.
When the physicists Prof. Stefan Karsch and Prof. Franz
Pfeiffer illuminate a tiny fly with X-rays, the resulting image captures even
the finest hairs on the wings of the insect. The experiment is a pioneering
achievement. For the first time, scientists coupled their technique for
generating X-rays from laser pulses with phase-contrast X-ray tomography to
visualize tissues in organisms. The result is a three-dimensional view of the
insect in unprecedented detail.
The X-rays required were generated by electrons that were
accelerated to nearly the speed of light over a distance of approximately one
centimeter by laser pulses lasting around 25 femtoseconds. A femtosecond is one
millionth of a billionth of a second. The laser pulses have a power of
approximately 80 terawatts (80 x 1012 watts). By way of comparison: an atomic
power plant generates 1,500 megawatts (1.5 x 109 Watt).