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151.
A high power dynamic fundamental mode Nd:YAG laser is experimentally demonstrated with a stagger-pumped laser module and a V-shaped resonator. The rod is pumped symmetrically by staggered bar modules. And dynamic fundamental mode is achieved under different pump levels. The maximal continuous wave (CW) output of 124 W (M2=1.4) is achieved with a dual rod. Average output of 112 W, pulse width of 120 ns, pulse energy of 11.2 mJ and peak power of 93 kW are obtained in Q-switched operation of 10 kHz. 相似文献
152.
Haigang Liu 《Optik》2010,121(4):351-357
Based on the generalized Huygens-Fresnel diffraction integral and beam coherence polarization (BCP) matrix formulation, the focusing properties of a type of non-uniformly polarized (NUP) beam through a spherical aberrated lens with annular aperture are studied. The dependence of focal shift, intensity distribution, power in the bucket (PIB) and degree of polarization on the spherical aberration coefficient, obscure ratio and polarization parameters is illustrated numerically. The focusing of NUP beams by a spherically aberrated lens with circular aperture is treated as a special case, where the inner radius of the aperture is equal to zero. 相似文献
153.
In this paper, semiconductor laser beam collimation lenses system has been optimum simulated and designed. The new design methods for aspheric cylinder lenses collimation system have been discussed in detail and the system parameters are calculated and optimized by using a geometrical ray optics approximation. The optical system has been further simulated by software MATLAB, and the simulation results showed that the emergence angle can be collimated effectively, and the output beam can be expanded to a circular spot in centimeter level beam radius. 相似文献
154.
The design of optical prism fingerprint scanner with aspheric lens is researched. We propose a modified structure for optical prism fingerprint scanner, which has an asymmetrical aspheric lens on the output plane. It is numerically shown under elliptic valley similar fingerprint model that the optical image qualities of such a scanner are better than the scanner with symmetrical aspheric lens. When the fingerprint range is 15 mm, the results show that the minimum image contrast is 0.49 for an optical prism with asymmetrical aspheric lens, much better than a symmetrical aspheric lens with 0.20. The relative illumination variation is from 0.62 to 1.00 for optical prism with asymmetrical aspheric lens, and for the symmetrical aspheric lens it is 0.35 to 1.00. We conclude that an optical prism with asymmetrical aspheric lens is better than an optical prism with symmetrical aspheric lens. 相似文献
155.
To improve the anterior surface biocompatibility of hydrophobic acrylic intraocular lens (IOL) in a convenient and continuous way, poly(ethylene glycol)s (PEGs) were immobilized by atmospheric pressure glow discharge (APGD) treatment using argon as the discharge gas. The hydrophilicity and chemical changes on the IOL surface were characterized by static water contact angle and X-ray photoelectron spectroscopy to confirm the covalent binding of PEG. The morphology of the IOL surface was observed under field emission scanning electron microscopy and atomic force microscopy. The surface biocompatibility was evaluated by adhesion experiments with platelets, macrophages, and lens epithelial cells (LECs) in vitro. The results revealed that the anterior surface of the PEG-grafted IOL displayed significantly and permanently improved hydrophilicity. Cell repellency was observed, especially in the PEG-modified IOL group, which resisted the attachment of platelets, macrophages and LECs. Moreover, the spread and growth of cells were suppressed, which may be attributed to the steric stabilization force and chain mobility effect of the modified PEG. All of these results indicated that hydrophobic acrylic IOLs can be hydrophilic modified by PEG through APGD treatment in a convenient and continuous manner which will provide advantages for further industrial applications. 相似文献
156.
157.
Polarized luminescence intensity reading and the polarized absorbance spectra of 4-diethyl-amino-4′-nitrostilbene “impurity” in the n-butyl-p/p-hexyloxyphenyloxycarbonyl/-phenyl-carbonate liquid crystal were measured. Degrees of orientational order, S1 and S2, of the nematic liquid were calculated from relative values of the absorbance and luminescence intensity components. A function, which describes the angular molecular distribution with respect to a preferred direction in the liquid crystal, is plotted. 相似文献
158.
超高数值孔径Schwarzschild投影光刻物镜的光学设计 总被引:4,自引:0,他引:4
针对45nm及以下节点光刻相关技术的研究需求,确定了实验型投影光刻物镜的结构型式及设计指标。依据像差理论在非同心小遮拦的Schwarzschild反射系统中添加折射补偿镜组来进一步减小系统的中心遮拦,扩大像方数值孔径。设计了一套小中心遮拦,数值孔径为1.20的Schwarzschild折反式投影光刻物镜。设计结果表明,该投影光刻物镜工作带宽为100pm,像方视场为50μm,线中心遮拦比为13%,光学分辨力为80nm时(6240lp/mm)的系统调制传递函数大于0.45,全视场最大畸变为6.5nm,满足了45nm深紫外(DUV)浸没光刻实验平台对投影光刻物镜的需求。 相似文献
159.
A significant growth of research on adaptive liquid lens is achieved over the past decades, and the field is still attracting increasing attentions, focusing on the transition from the current stage to the commercialized stage. The challenges faced are not limited to fabrication, material, small tuning range in focal lengths, additional control systems, limitations in special actuation methods and so on. In addition, the use of external driving parts or systems induce extra problem on bulky appearance, high cost, low reliability etc. Therefore, adaptive liquid lens will be an interesting research focus in both microfluidics and optofluidics science. This review attempts to summarize and focus on the droplet profile deformation under different driving mechanisms in tunable liquid microlens as well as the application in cameras, cell phone and so on. The driving techniques are generally categorized in terms of mechanisms and driving sources. 相似文献
160.
报道位相型电控聚合物分散液晶(H-PDLC)全息衍射透镜的研制及特性研究,理论上,根据耦合波理论,研究了不同的相分离程度系数下,理想位相型电控聚合物分散液晶(H-PDLC)全息衍射透镜在可见光波长(400—800nm)的衍射特性.实验研制了衍射效率最高为70%的电控H-PDLC变焦透镜样品,研究表明H-PDLC透镜具有优良的成像特性,和快速响应的电控开关特性,在光学成像系统,光通信系统中具有良好的应用前景. 相似文献