Browsing by Author "Zhang, Z."

Now showing 1 - 3 of 3
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    Analytical brightness compensation algorithm for traditional polygon-based method in computer-generated holography
    Pan, Y. J.; Wang, Y. T.; Liu, J.; Li, X.; Jia, J.; Zhang, Z. (Optical Society of America, 2013-06-01)
    In three-dimensional (3D) holographic display, current brightness compensation algorithm of the traditional polygon-based method experimentally obtains the compensation factor, which depends on the fabrication process. In this paper, we proposed an analytical brightness compensation method discarding the influence of the fabrication. The surface property function with the flat power spectral density and the compensation factor obtained from the simplified relationship between the original and the rotated frequencies are used to analytically compensate the radiant energy of the tilted polygon. The optical reconstruction results show the proposed method could effectively compensate the brightness and ensure the further shading process. The proposed method separates the brightness compensation from the fabrication process, which is important for deepening the investigation of the hologram fabrication and achieving realistic 3D reconstruction. (C) 2013 Optical Society of America
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    Characterizing ultrashort optical pulses using second-order nonlinear nanoprobes
    Li, H. F.; Zhang, Z.; Xu, Q. A.; Shi, K. B.; Jia, Y. S.; Zhang, B. G.; Xu, Yong; Liu, Z. W. (AIP Publishing, 2010-12-01)
    We report a second-order nonlinear nanoprobe for characterizing ultrafast optical near fields. The proposed nanoprobe comprises second harmonic nanocrystals attached to a carbon nanotube, which is in turn attached to a silica fiber taper. We demonstrate in situ pulse characterization directly in the air core of a photonic crystal fiber. Further, it is shown that nanoprobes containing a single nanocrystal in the tip of the nanotube can be fabricated by auxiliary focused ion beam nanomilling. These results indicate that the proposed nanoprobe can open an avenue for probing the evolution of ultrafast optical fields in complex three-dimensional micro-or nanostructures. (C) 2010 American Institute of Physics. [doi:10.1063/1.3532112]
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    A vanished history of skeletonization in Cambrian comb jellies
    Ou, Q.; Xiao, S.; Han, J.; Sun, G.; Zhang, F.; Zhang, Z.; Shu, D. (2015-07)
    Ctenophores are traditionally regarded as "lower" metazoans, sharing with cnidarians a diploblastic grade of organization. Unlike cnidarians, where skeletonization (biomineralization and sclerotization) evolved repeatedly among ecologically important taxa (for example, scleractinians and octocorals), living ctenophores are characteristically soft-bodied animals. We report six sclerotized and armored ctenophores from the early Cambrian period. They have diagnostic ctenophore features (for example, an octamerous symmetry, oral-aboral axis, aboral sense organ, and octaradially arranged ctene rows). Unlike most modern counterparts, however, they lack tentacles, have a sclerotized framework, and have eight pairs of ctene rows. They are resolved as a monophyletic group (Scleroctenophora new class) within the ctenophores. This clade reveals a cryptic history and sheds new light on the early evolution of this basal animal phylum. Skeletonization also occurs in some other Cambrian animal groups whose extant members are exclusively soft-bodied, suggesting the ecological importance of skeletonization in the Cambrian explosion.