In this paper, a curvelet-based noise suppression bilinear interpolation method for low-dose CT images is proposed. Curvelets provide a multidirectional and multiscale decomposition that has been mathematically shown to represent distributed discontinuities such as edges better than traditional wavelets. Because the traditional linear interpolation results in boundary fuzziness in interpolated images, combined with the advantages of curvelet transform, here we propose a curvelet-based modified bilinear interpolation to improve the accuracy of interpolation. Extensive experiments indicate that the proposed method can effectively improve the quality of the obtained target image based on low-dose CT images and the produced slice image is similar to original slice image.
On the basis of the mechanically scratching using the Atomic Force Microscope, this paper proposes a new method for manufacturing high frequency grating. The grating was fabricated on a polycarbonate compact disc with a silicon AFM tip under the contact mode. The fabrication technique and the optimization of parameters for the technique are discussed in detail. From the experiment, the minimum spacing of the grating can reach 30 nm. The digital nano-moire patterns verify that the grating has good potential to be applied to the nano-deformation measurement.
In this paper, some novel micro/nano- moire grating fabricating techniques are introduced. The gratings are produced by the SPM lithography, FIB lithography, and molecular beam epitaxy (MBE) method. The moire patterns formed with these gratings are also introduced. The gratings are successfully to be used to measure the residual deformation in the surface around a step edge of the Al/Si artificial nanocluster with the moire methods. The successful experimental results verify the feasibility of these methods.