Nikon Metrology

CT scan – The symmetry of starfish

Computed tomography, X-ray and CT Inspection

See the structure of a starfish visualized with X-ray CT. The mesmerizing X-ray CT scan of a Starfish (seen below) was acquired by Dr. Andrew Mathers using a Nikon XT H 225 ST.


X-ray scan image of a starfish in four quadrants

This X-ray CT scan of a Starfish was acquired by Dr. Andrew Mathers, using a Nikon XT H 225 ST.


This X-ray CT scan of a Starfish was acquired by Dr. Andrew Mathers at 50 µm voxel resolution and 37 Watts, using a Nikon XT H 225 ST. The XT H 225 ST system houses a Nikon 225 kV microfocus X-ray source fitted with a tungsten reflection target and a 1 mm Copper beam filter, coupled with a Varex 4343CT flat panel detector. For this scan the detector acquired 4492 projections at an exposure of 708 mS and a gain of 24 dB. X-ray CT data was reconstructed using a modified Filtered Back Projection algorithm in Nikon CT Pro 3D and rendered in 3D using the isosurface renderer in Volume Graphics Studio Max 3.4. Individual 2D slices in the Top-Down view were saved as a video file in Volume Graphics, to show the change in structure throughout the starfish producing a semi-kaleidoscopic result.

Watch the video on LinkedIn.



The XT H 225 ST is a Computed Tomography (CT) system ideally suited to a wide range of materials and sample sizes, especially those that are too large or heavy for other systems in the range. the system has three interchangeable sources; the 225 kV reflection target, 180 kV transmission target and the optional 225 kV rotating target. Combined with the wide range of flat panel detectors to choose from, the ST system provides a flexible tool for quality laboratories, production facilities and research departments.


  • Proprietary 225 kV microfocus X-ray source with 3 µm focal spot size
  • Easy system operation
  • Stunning images providing maximum insight
  • High performance image acquisition and volume processing
  • Straightforward inspection automation
  • Safety by design
  • Low cost-of-ownership

Find out more about the XT H 225 ST.