The micro-CT system has been developed for small animal imaging. The system is mainly composed of CCD detector coupled with CsI (Tl) phosphor, X-ray source with micro focal spot, linearly moving couch, and rotation gantry. This system was developed as a gantry rotation type and designed to get CT images of small living animals. In this paper, the requirements of main parts of the system to acquire micro spatial resolution are described. The characteristics of the system, such as field of view, geometries of main components, gantry movement, and X-ray analysis are mainly considered. Resolution of the CT system was evaluated under variable conditions. Typically, the spatial resolution of the CT system was obtained about 37 micron at 10% of MTF curve.
We demonstrate compact transmission soft X-ray microscope system with 50 nm spatial resolution for the life and physical science. This x-ray microscope operates at photon energy from 284 eV to 543 eV, so called 'water window' region (2.3~4.4nm), where natural contrast between <i>carbon</i> (protein) and <i>oxygen</i>(water) allows imaging of unstained biological material in their natural, hydrated environment. The compact transmission soft x-ray microscope is based on a laser plasma x-ray source, tandem ellipsoidal condenser reflective optics, diffractive zone plate optics and x-ray sensitive charge-coupled device (CCD) to record an x-ray image. The source is a liquid-jet target laser plasma source, which is practically debris free and suitable for high average power operation. The flux, brightness and bandwidth of this source has been simulated and optimized for X-ray microscopy for biology application. A tandem ellipsoidal reflective mirror operates as condenser and illuminates the sample. The high resolution imaging is currently performed with a ~12% efficient nickel zone plate with an outmost zone width of 35nm. In conclusion, we suggested a possibility of the compact soft x-ray microscopy system with 50 nm spatial resolution as a suitable tool for the wide range of studies such as biological imaging, environmental samples, and nanostructure analysis.
A compact soft X-ray microscope system has been developed for biological applications with nano-scale resolution. Soft X-ray used to the system is emitted from a solid target by using Nd-YAG pulsed laser. Boron nitride (BN) is used as the target materials in the system. The optics of the microscope system is adopted with wolter type-I mirrors, which is consisted of a condenser mirror with demagnification of 1/4× and an object mirror with magnification of 32×. The surface roughness of the machined wolter mirrors is about 0.8 nm (Ra) after polishing. In this paper, the X-ray characteristics, i.e., spectrum and intensity emitted from laser plasma-based x-ray source was measured. Imaging test using the system was performed with gold 2000 mesh. The spatial resolution of the soft x-ray microscope system was obtained about 900 nm.