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911.
以角谱传播理论和分数傅里叶变换(FRFT)的单透镜和双透镜光学实现单元为理论基础,提出了一种基于实际光学结构的光学FRFT的数值模拟算法,推导了该算法中采样间隔的选取方法,并利用Matlab语言编写了相应的处理程序,将该程序对方孔分数傅里叶变换的计算结果与实际实验结果相比较,结果表明该算法是实际光学结构在理想情况下的模拟,因此,该数值计算在一定程度上可以代替柱面镜对光场实现分数傅里叶变换,也可以为实际实验提供很好的参考和指导。  相似文献   
912.
光学图像处理技术能以复振幅、并行、高速度和巨量互连来处理信号。利用光学方法的半色调网屏技术实现了红外图像的假彩色编码,提高了红外图像的可识别性;利用光学相关识别技术构造了一种基于4f系统的光学图像实时相关识别系统,以实现对红外图像的实时处理和识别。  相似文献   
913.
掺Ag纳米颗粒的BaTiO3复合薄膜的非线性光学特性   总被引:1,自引:1,他引:1       下载免费PDF全文
通过准分子激光(XeCl,308 nm,20 ns)在MgO(100)单晶衬底上制备了不同掺杂浓度的Ag:BaTiO3纳米复合薄膜,通过X射线衍射和X射线光电子能谱对薄膜的结构和组分进行了表征.在430 nm和470 nm附近观测到了不同浓度Ag纳米颗粒引起的等离子体吸收峰,通过z扫描技术对复合薄膜的三阶非线性光学特性进行了测量,并对其光学非线性的增强机制进行了讨论.  相似文献   
914.
Polycrystalline zinc nitride films are deposited on Coming 7059 glass substrates by pulsed filtered cathodic vacuum arc deposition (PFCVAD). The crystallographic structure is studied by means of x-ray diffraction. These measurements show that all the films are crystallized in the cubic structure, in a preferred orientation along the (332) and (631) directions. Weak XRD signal shows small crystallites distributed in an amorphous tissue. A small improvement of crystallinity is observed with annealing. Optical parameters such as absorption, energy band gap, Urbach tail, extinction coefficients have been determined. The Urbach tail energy is decreased with annealing at 500℃ for one hour. Energy band gap values are found to be increased by annealing.  相似文献   
915.
徐斌  程正则  易林  成泽 《中国物理》2007,16(12):3798-3802
With the help of ab initio full-potential linearized augmented plane wave (FPLAPW) method, calculating the electronic structure and linear optical properties is carried out for XCd2(SO4)3 (X =Tl, Rb). The results show that Tl2Cd2(SO4)3 (TlCdS) has a larger band gap than Rb2Cd2(SO4)3 (RbCdS) and the energy bands for RbCdS are more dispersive than those of TlCdS. From their partial densities of states (PDOS), we have observed that the hybridization between S ionic 2p and O atomic 2p orbitals forms SO4 ionic groups. The remarkable difference between RbCdS and TlCdS is, however, the degree of hybridization between cation (Tl and Rb) and its surrounding oxygen atoms. In the view of quantum chemistry, the strong p-d hybridization indicates the existence of their cation ionic bonds (Cd-O, Rb-O, and Tl-O). The calculations of TlCdS and RbCdS show their optical properties to be less anisotropic. Their anisotropies in the optical properties mainly occur in a low photon energy region of 5-16 eV.  相似文献   
916.
《发光学报》2007,28(6):874-874
《发光学报》是中国物理学会发光分会与中国科学院长春光学精密机械与物理研究所共同主办的中国物理学会发光分会的学术会刊。该刊是以发光学、凝聚态物质中的激发过程为专业方向的综合性学术刊物。  相似文献   
917.
《大学物理》2007,26(12):63-63
北京欧普特科技有限公司自成立以来一直致力于光学精密仪器、光学零件的设计、开发与加工生产,基于长期为国际市场加工生产传统高精度光学零件的基础,我公司严格参照国际通常规格及技术指标,备有完整系列的精密光学零部件(备有产品样本供参考)供国内各大专院校、科研机构、试验室随时选用,我公司同时叮为您的应用提供技术咨询,我公司有超过10年的红外材料销售、加工经验,可以提供美国及欧洲产的优质红外光学材料,  相似文献   
918.
We use a diamond anvil cell for the first time to investigate the Raman spectra of an aqueous micellar solution of hexadecyltrimethylammonium bromide (CTAB) at pressures up to 3.85 GPa. The pressure-induced phase transition between the micellar and coagel phases is found to occur at 0.64 GPa and 60℃. This phase transition has a pressure hysteresis, and thus exhibits the first-order phase transition properties. Further experimental results show that although the structure of the coagel phase is similar to that of the CTAB crystal, the interchain distance is slightly larger in the coagel phase than that in the CTAB crystal.  相似文献   
919.
Due to many experimental data required and a lot of calculations involved, it is very complex and cumbersome to model prism-based liquid-refractive-index-measuring methods. We develop a new method of mathematical modelling for measuring refractive index of a liquid based upon the Fresnel formula and prism internal reflection at an incident angle less than the critical angle. With this method, only two different concentrations measurements for a kind of solution can lead to the determination of computational model. Measurements are performed to examine the validity of the theoretical model. Experimental results indicate the feasibility of the theoretical model with an error of 1%. The method is also capable of measuring even smaller changes in the optical refractive index of the material on a metal surface by the surface plasma resonance sensing techniques.  相似文献   
920.
Two-photon photopolymerization (TPP) of femtosecond laser is a promising method to fabricate three-dimensional woodpile photonic crystals (PCs). We build micro-fabricatlon system based on the principle of TPP. Three- dimensional woodpile PCs consisting of in-plane rod distances ranging from 1000nm to 2000nm are fabricated by focusing femtosecond laser in photosensitive liquid resin ORMOCER. The properties of the PCs are also discussed, and fundamental photonic band gaps in middle-infrared range are measured, whose in-plane rod distances are 1500nm and 2000 nm. Three-dimenslonal woodpile PC devices with desired defects, such as cross-waveguide and micro-laser structures, are introduced easily by TPP. We fabricate the three-dimensional woodpile PCs in the liquid resin at the fast scanning speed of 120μm/s.  相似文献   
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