Microcomputed tomography (Micro-CT) uses an X-ray source to visualise the surface and internal structures of a specimen in three dimensions, without extensive or destructive specimen preparation. The maximum resolution attainable with Micro-CT depends on the size of the sample being scanned as well as the equipment. Generally, each additional millimetre of sample diameter increases pixel dimensions by one micron e.g. a 15mm diameter bone will comfortably scan at 15 micron pixel resolution.
During scanning, the specimen is rotated in small angular increments over 180°C or 360°C and an X-ray projection image is captured at each step. After scanning, reconstruction software is used to turn the projection images into a stack of hundreds or even thousands of cross-sections which can be used with a variety of image analysis and volume rendering software packages for 2-D or 3-D morphometrical analysis, or to produce 3-D images and animations.
Micro-CT relies on a density difference between the structure of interest and the surrounding material. Porous materials (minerals, ceramics, polymers) are particularly well suited to this method. Other applications include bone, teeth, lung tissue, archaeological and paleontological specimens, coral, and wood.
X-ray energy range: 20 kV - 160 kV.
This instrument is designed to accommodate both large (up to 140mm diameter) and small samples of varying composition. Larger or denser specimens can take advantage of higher beam energies (160kV up to 16W), while higher resolution features (~0.5um) can be achieved when scanning smaller samples. Our system has four X-ray cameras for ultimate flexibility: three CCD cameras with different resolution and field of view, and one large-area flat panel detector. The three CCDs can take images in the central beam position and in two offset positions to double the field of view, with the offset images automatically stitched together during reconstruction. The included filter wheel with intergrated automatic parameter recommendation functionality allows the system to cope with a wide range of sample types from soft tissue to concrete or ceramics.
X-ray energy range: 20 kV - 100 kV.
The Skyscan 1272 can achieve a spatial resolution of approximately 2-3um under ideal conditions and is fitted with an automated sample changer capable of handling up to 16 specimens. Sample sizes are restricted to cylinders approximately 50mm tall and 20mm in diameter but on request it can operate without the automated changer to accommodate cylindrical samples up to 100 x 70mm. The included 4 beam filters make it ideal for a wide range of sample types including biological samples or denser materials such as concrete <~20mm diameter.
X-ray energy range: 20 kV - 100 kV.
The maximum resolution attainable with this system is approximately 4 µm. At lower magnifications (~15-24 µm voxels) sample sizes may be as big as 5 cm3, while at higher resolutions the maximum sample size may be 4-5 mm3.
A Materials Testing Stage is also available for this system allowing for in-situ tensile and compressions tests.
X-ray energy range: 40 kV - 150 kV.
The maximum sample size that can be imaged in this system is 40 mm diameter. Taller samples can be scanned (up to 200 mm) and then stitched together in post processing. The MicroXCT-400 is capable of submicron resolution (0.7 µm) for samples smaller than 1 mm in diameter. It collects images in absorption contrast mode making it suitable to image a wide range of specimens including both hard and soft biological tissues as well as minerals, ceramics, polymers etc.