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71.
基于自再现原理,利用菲涅耳-基尔霍夫衍射积分方程,引入腔镜失调、激光介质上的增益分布以及光阑口径,采用本征矢量法分析了大口径平凹腔薄片激光器的本征模式,并计算了相应的光束质量因子M2.建立了千瓦级薄片激光系统和光纤扫描光斑诊断装置,开展了高功率激光输出特性研究.结果表明,在大口径高功率平凹腔中多个本征模式可同时起振,获... 相似文献
72.
Positive solutions for an elliptic equation in an annulus with a superlinear nonlinearity with zeros
We study existence, multiplicity, and the behavior, with respect to λ, of positive radially symmetric solutions of in annular domains in . The nonlinear term has a superlinear local growth at infinity, is nonnegative, and satisfies for a suitable positive and concave function a. For this, we combine several methods such as the sub and supersolutions method, a priori estimates and degree theory. 相似文献
73.
WANG Yang GU Donghong GAN Fuxi 《Chinese Journal of Lasers》2001,10(3):206-210
1 Introduction Recentlyopticaldisksabletostorealargequantityofinformationhavebeenusedascompactdisk (CD ) ,digitalversatiledisk(DVD) ,andtheirrecordableorrewritabletypes(suchasCD R ,CD RW ,DVD R ,andDVD RAM ) [1 ] .Anopticaldiskisakindofmultilayersystemdepositedona… 相似文献
74.
对光盘用2P胶的应用研究进展情况进行了评述,其中光盘制备用光聚合浮雕成型2P胶的基本组成为各类多官能团丙烯酸酯类单体;光盘保护涂层用2P胶主要组分为环氧丙烯酸酯类预聚体。 相似文献
75.
基于广电行业的实际应用,设计了一种数字视频存储与检索系统,并对系统的结构、原理及其实现方法进行了论述。 相似文献
76.
Roohollah Torabi Kachoosangi Gregory G. Wildgoose Richard G. Compton 《Electroanalysis》2007,19(14):1483-1489
The voltammetric response of graphite or carbon nanotube paste electrodes, which incorporate the room temperature ionic liquid, N‐butyl‐N‐methyl pyrrolidinium bis(trifluoromethylsulfonyl) imide or [C4mpyrr][NTf2], (RTIL‐CNTPE and RTIL‐CPE respectively) as the binder, towards anionic, cationic and neutral redox probes is examined and compared to conventional paste electrodes which use mineral oil as the binder. The RTIL paste electrodes are found to suffer from very large background currents due to capacitive charging. This is exacerbated further when CNTs are combined with RTILs in the paste. The large charging currents obscure any Faradaic processes of interest, especially at low analyte concentrations. By employing steady state voltammetry at a rotating disk electrode made of the RTIL pastes this problem can be overcome. This allows the electroanalytical properties of these interesting electrode substrates, which combine the attractive properties of CNTs with RTILs to be further explored and developed. 相似文献
78.
79.
“Laser-assisted magnetic recording”, in which a recording media is heated by a laser beam while writing data, is attracting
attention as a technology that enables a recording density of 1 Tb/in.2. There exists another technology for media in which the recording layer is constructed with many small projections that enable
high magnetic coercivity. This is called “patterned media”. For developing hard disk drives using these methods, we developed
a simulator that analyzes the optical intensity distribution from the optical head for laser-assisted recording and the temperature
profile on the patterned media. The simulator calculates the optical model using the finite-difference time-domain (FDTD)
method. The thermal analysis of the three-dimensional model allows fast calculations using the alternating direction implicit
(ADI) method. The heat source distribution data for thermal analysis is calculated in order to use the results of optical
analysis. The optical and thermal analyses of the laser-assisted recording model were investigated with the simulator. 相似文献
80.
Theoretical Analysis of Super-Resolution Optical Disk Mastering Using a Photoreactive Dye Mask Layer
The super-resolution mastering of read-only optical disks using a photoreactive bleachable dye mask layer was theoretically analyzed. Equations have been derived which describe the photoreactions of the resist layer and mask layer. A numerical simulation based on these equations showed that the transmittance of the mask directly affects the quality of the formed pit shape. A high-quality pit shape is obtained by using a low transmittance mask. 相似文献