High-resolution computed tomography with a compact soft x-ray microscope.
Computed tomography based on high-resolution soft x-ray microscopy utilizes the natural contrast for biological specimens provided by the water window (lambda = 2.4 - 4.4 nm) and the high resolving power of zone plate objectives. It is capable of revealing the 3D structure of biological specimens at sub-visible-microscopic resolution. To date, the technique has only been available at synchrotron-based microscopes, which limits the researchers access. In the present paper we demonstrate high-resolution soft x-ray tomography with a laboratory zone-plate-based soft x-ray microscope. The specimen, a diatom mounted on a glass capillary, was reconstructed from a tilt series of 53 images covering 180 degrees using a filtered back projection algorithm. The resolution of the tomogram was estimated to a half period of 140 nm using a differential-phase-residual method. Cryo-fixation, increased source brightness and extended-depth-of-focus objectives are important for pushing the resolution of compact systems for biological samples.
Bertilson
Michael
M
Department of Applied Physics, Royal Institute of Technology/AlbaNova, Stockholm, Sweden. michael.bertilson@biox.kth.se
von Hofsten
Olov
O
Vogt
Ulrich
U
Holmberg
Anders
A
Hertz
Hans M
HM
D000465:Algorithms; D020285:Cryoelectron Microscopy / Q000379:methods; D017377:Diatoms; D004867:Equipment Design; D007091:Image Processing, Computer-Assisted; D008853:Microscopy / Q000379:methods*; D055096:Optical Devices; D055095:Optics and Photonics; D017785:Photons; D012822:Silicon Dioxide / Q000737:chemistry; D017356:Synchrotrons; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014965:X-Rays
D012822:Silicon Dioxide