We fabricated a new type of two-dimensional photonic crystal slab filter. The resonant cavities were directly put into the waveguide arms. The optical transmissions of the filters were measured and the results show th...We fabricated a new type of two-dimensional photonic crystal slab filter. The resonant cavities were directly put into the waveguide arms. The optical transmissions of the filters were measured and the results show that the optimized two-channel filters give good intensity distribution at the output ports of the waveguide. A minimum wavelength spacing of 5 nm of the filter outputs is realized by accurately controlling the size of the resonant cavities.展开更多
An optical code generating device for security access system application is presented. The code generating device constructed using asymmetric hollow optical waveguide coupler design provides a unique series of output...An optical code generating device for security access system application is presented. The code generating device constructed using asymmetric hollow optical waveguide coupler design provides a unique series of output light intensities which are successively used as an optical code. The design of the waveguide is made using two major components which are asymmetric Y-junction splitter and a linear taper. Waveguiding is done using a hollow waveguide structure. Construction of higher level 1×N hollow waveguide coupler is done utilizing a basic 1×2 asymmetric waveguide coupler design together with a cascaded design scheme. Non-sequential ray tracing of the asymmetric hollow optical waveguide couplers is performed to predict the optical transmission properties of the waveguide. A representation of the code combination that can be generated from the device is obtained using combinatory number theory.展开更多
An interior point of a finite planar point set is a point of the set that is not on the boundary of the convex hull of the set. For any integer k ≥ 1, let h(κ) be the smallest integer such that every set of points...An interior point of a finite planar point set is a point of the set that is not on the boundary of the convex hull of the set. For any integer k ≥ 1, let h(κ) be the smallest integer such that every set of points in the plane, no three collinear, with at least h(κ) interior points, has a subset of points with exactly κ or κ + 1 interior points of P. We prove that h(5)=11.展开更多
基金Project supported by the National Key Basic Research and Development Programme of China (Grant No 2001CB6104), the National Center for Nanoscience and Technology, China (Grant No 2003CB7169) and the National Natural Science Foundation of China (Grant No 10474036).
文摘We fabricated a new type of two-dimensional photonic crystal slab filter. The resonant cavities were directly put into the waveguide arms. The optical transmissions of the filters were measured and the results show that the optimized two-channel filters give good intensity distribution at the output ports of the waveguide. A minimum wavelength spacing of 5 nm of the filter outputs is realized by accurately controlling the size of the resonant cavities.
基金Universiti Teknologi MARA for the financial support on this project.
文摘An optical code generating device for security access system application is presented. The code generating device constructed using asymmetric hollow optical waveguide coupler design provides a unique series of output light intensities which are successively used as an optical code. The design of the waveguide is made using two major components which are asymmetric Y-junction splitter and a linear taper. Waveguiding is done using a hollow waveguide structure. Construction of higher level 1×N hollow waveguide coupler is done utilizing a basic 1×2 asymmetric waveguide coupler design together with a cascaded design scheme. Non-sequential ray tracing of the asymmetric hollow optical waveguide couplers is performed to predict the optical transmission properties of the waveguide. A representation of the code combination that can be generated from the device is obtained using combinatory number theory.
基金Supported by the National Natural Science Foundation of China(10901045,11171088)Supported by the NSF of Hebei Province(A2010000828)Supported by the SF of Hebei University of Science and Technology(QD200955)
文摘An interior point of a finite planar point set is a point of the set that is not on the boundary of the convex hull of the set. For any integer k ≥ 1, let h(κ) be the smallest integer such that every set of points in the plane, no three collinear, with at least h(κ) interior points, has a subset of points with exactly κ or κ + 1 interior points of P. We prove that h(5)=11.