Kinoform单透镜可以高效聚焦硬X射线至纳米量级,在X射线纳米显微学和纳米光谱学领域有着重要的应用前景.基于衍射光学和傅里叶光学理论,给出了X射线经由Kinoform单透镜聚焦的物理模型,基于数值模拟,研究了不同材料、光子能量、台阶数量...Kinoform单透镜可以高效聚焦硬X射线至纳米量级,在X射线纳米显微学和纳米光谱学领域有着重要的应用前景.基于衍射光学和傅里叶光学理论,给出了X射线经由Kinoform单透镜聚焦的物理模型,基于数值模拟,研究了不同材料、光子能量、台阶数量和顶点曲率半径对Kinoform单透镜聚焦性能的影响.结果表明,孔径为1 mm的Kinoform单透镜对30 ke V的X射线聚焦,可以得到14 nm焦斑、62μm焦深,且可实现4个量级的光强增益和大于30%的光强透过率.展开更多
We propose a computational method for generating sequential kinoforms of real-existing full-color three- dimensional （3D） objects and realizing high-quality 3D imaging. The depth map and color information are obtain...We propose a computational method for generating sequential kinoforms of real-existing full-color three- dimensional （3D） objects and realizing high-quality 3D imaging. The depth map and color information are obtained using non-contact full-color 3D measurement system based on binocular vision. The obtained full-color 3D data are decomposed into multiple slices with RGB channels. Sequential kinoforms of each channel are calculated and reconstructed using a Fresnel-diffraction-based algorithm called the dynamic- pseudorandom-phase tomographic computer holography （DPP-TCH）. Color dispersion introduced by different wavelengths is well compensated by zero-padding operation in the red and green channels of object slices. Numerical reconstruction results show that the speckle noise and color-dispersion are well suppressed and that high-quality full-color holographic 3D imaging is feasible. The method is useful for improving the 3D image quality in holographic displays with pixelated phase-type spatial light modulators （SLMs）.展开更多
The results of experiments on the synthesis of the off-axis quantized kinoforms of binary objects with the use of the weighting iterative Fourier transform （WIFT） algorithm are presented. Kinoforms are registered wi...The results of experiments on the synthesis of the off-axis quantized kinoforms of binary objects with the use of the weighting iterative Fourier transform （WIFT） algorithm are presented. Kinoforms are registered with a liquid-crystal spatial light modulator （SLM）. A simple procedure to introduce the carrier frequency into the structure of an axial kinoform is proposed. An image reconstructed by an off-axis kinoform is free from the noises with the zero and close frequencies caused by the imperfection of both the phase mode of operation of the SLM and the effects of quantization of the registered phase. Data on the diffraction efficiency are also given.展开更多
文摘Kinoform单透镜可以高效聚焦硬X射线至纳米量级,在X射线纳米显微学和纳米光谱学领域有着重要的应用前景.基于衍射光学和傅里叶光学理论,给出了X射线经由Kinoform单透镜聚焦的物理模型,基于数值模拟,研究了不同材料、光子能量、台阶数量和顶点曲率半径对Kinoform单透镜聚焦性能的影响.结果表明,孔径为1 mm的Kinoform单透镜对30 ke V的X射线聚焦,可以得到14 nm焦斑、62μm焦深,且可实现4个量级的光强增益和大于30%的光强透过率.
基金supported by the National Natural Science Foundation of China (No. 60772124)the International Cooperation Project of Science and Technology Commission of Shanghai Municipality (No. 09530708700)the Shanghai University Innovation Funds for Graduates (Nos. SHUCX101060 and SHUCX102195)
文摘We propose a computational method for generating sequential kinoforms of real-existing full-color three- dimensional （3D） objects and realizing high-quality 3D imaging. The depth map and color information are obtained using non-contact full-color 3D measurement system based on binocular vision. The obtained full-color 3D data are decomposed into multiple slices with RGB channels. Sequential kinoforms of each channel are calculated and reconstructed using a Fresnel-diffraction-based algorithm called the dynamic- pseudorandom-phase tomographic computer holography （DPP-TCH）. Color dispersion introduced by different wavelengths is well compensated by zero-padding operation in the red and green channels of object slices. Numerical reconstruction results show that the speckle noise and color-dispersion are well suppressed and that high-quality full-color holographic 3D imaging is feasible. The method is useful for improving the 3D image quality in holographic displays with pixelated phase-type spatial light modulators （SLMs）.
文摘The results of experiments on the synthesis of the off-axis quantized kinoforms of binary objects with the use of the weighting iterative Fourier transform （WIFT） algorithm are presented. Kinoforms are registered with a liquid-crystal spatial light modulator （SLM）. A simple procedure to introduce the carrier frequency into the structure of an axial kinoform is proposed. An image reconstructed by an off-axis kinoform is free from the noises with the zero and close frequencies caused by the imperfection of both the phase mode of operation of the SLM and the effects of quantization of the registered phase. Data on the diffraction efficiency are also given.
