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简单地介绍了金属光学零件的特点及其车削加工的原理。以具体实例说明了金属光学零件的精密加工过程,同时介绍了金属光学零件的测量方法。 相似文献
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超声波清洗技术及应用 总被引:1,自引:0,他引:1
超声波是频率在人耳听觉范围上限(16kHz~20kHz)以上的声波,超声波因其频率高、方向性强、穿透本领大,尤其是在液体中能产生空化现象等特点,已被广泛应用到许多领域。超声波应用技术甚多,主要分为检测超声、医学超声、声表面波、功率超声及高频超声等,超声波清洗技术(以下简称“超声清洗”)是功率超声应用最广泛的一种。超声清洗有时被称“无刷清洗”,把工件放入超声清洗机中,无需任何刷、搓、滚动等清洗动作,污物“自动”从工件表面脱落,一会儿就干净如新,看起来非常神奇,那么,它究竟是怎样清洗的呢? 相似文献
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超声波清洗设备的发展方向目前有二个:一个是从单缸机到多缸机或自动化的超声清洗生产线;另一个是,从低频超声清洗机到高频超声清洗机。 相似文献
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介绍了新颖的纳米结构亚波长光学器件的特点,从器件的基本功能特性和工作机理两个方面详细讨论了其应用状况,并阐述了纳米制造技术对亚波长光学器件发展的重要推动作用及这一领域今后的研究热点。 相似文献
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The density distribution of a supersonic turbulent boundary layer is measured with the nanoparticle-based planar laser scattering technique, and the temporal evolution of its optical path difference (OPD) in a short time interval is characterized by proper orthogonal decomposition (POD). Based on the advantage of POD in capturing the energy of a signal, a temporal evolution model is suggested for the POD coefficients of OPD. In this model, the first few coefficients vary linearly with time, and the others are modeled by Gaussian statistics. As an application, this method is used to compute the short-exposure optical transfer function. 相似文献
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Temporal evolution of the optical path difference of a supersonic turbulent boundary layer 下载免费PDF全文
The density distribution of a supersonic turbulent boundary layer is measured with the nanoparticle-based planar laser scattering technique, and the temporal evolution of its optical path difference (OPD) in a short time interval is characterized by proper orthogonal decomposition (POD). Based on the advantage of POD in capturing the energy of a signal, a temporal evolution model is suggested for the POD coefficients of the OPD. In this model, the first few coefficients vary linearly with time, and the others are modeled by Gaussian statistics. As an application, this method is used to compute the shortexposure optical transfer function. 相似文献
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超声速光学头罩在大气层内飞行时, 需要在光学窗口表面顺来流方向进行喷流冷却, 致使窗口上方流场更为复杂. 目标光线穿过窗口上方流场, 受到激波、膨胀波、混合层、湍流边界层等流场结构引起的变密度场影响而产生波前畸变, 导致成像出现偏移、抖动、模糊等气动光学效应. 本文对马赫数3.8来流条件下有无喷流时超声速光学头罩流场引起的气动光学波前畸变进行了试验研究. 基于纳米示踪的平面激光散射技术, 首先对流场图像进行密度校准获得高时空分辨率密度场, 然后采用光线追迹法计算得到波长532 nm平面光波垂直于光学窗口穿过流场后的光程差(optical path difference, OPD)分布, 并对窗口上方近壁区有无喷流状态的流场结构引起的 OPD分布进行了研究. 发现无喷流时, 流场结构相对较为简单, 窗口上方有较长的回流区和层流区, 而有喷流时窗口上方出现复杂的剪切层、混合层及湍流边界层, 流动很快就转捩为湍流结构, 其引起的气动光学畸变要明显高于无喷流状态. 无喷流状态相隔5 μs的流场引起的光程差均方根值分别为0.0348 和0.0356 μm, 有喷流状态的光程差均方根值分别为0.0462 和0.0485 μm.
关键词:
超声速
喷流
气动光学
光程差 相似文献
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基于全息光学理论分析了全息光学元件的高斯成像性质,包括光焦度、成像位置、衍射效率以及作为光纤光谱仪光栅元件的可行性,并以全息光栅的成像理论以及光谱仪工作原理为基础,设计了光谱仪器光学系统的各个参数,通过Zemax软件的仿真、像质评价及优化,得出最终的参数和模拟结果。所使用的全息光栅记录波长为575 nm,记录光束之间的夹角为10,一束为平面波,一束为球面波,焦距40 mm,使用+1级衍射光,光栅孔径为10 mm。光谱仪的工作波长范围为400 nm~800 nm,体积140 mm*30 mm*40 mm,谱面展宽29.1 mm。通过在光学平台上搭建光路,利用已研发完成的电路系统及光谱仪软件,针对汞灯光谱进行了试验,光谱分辨率优于8 nm,测量得到的汞灯光谱与标准汞灯光谱一致,表明了所设计的基于全息元件的光纤光谱仪光学系统是可行的。 相似文献
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Motivated by protocols [G. Gordon, G. Rigolin, Phys. Rev. A 73 (2006) 062316] and [N.B. An, G. Mahler, Phys. Lett. A 365 (2007) 70], we propose a linear optical protocol for quantum state sharing of polarization entangled state in terms optical elements. Our protocol can realize a near-complete quantum state sharing of polarization entangled state with arbitrary coefficients, and it is possible to achieve unity fidelity transfer of the state if the parties collaborate. This protocol can also be generalized to the multi-party system. 相似文献
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用于衍射光学元件优化设计的遗传算法及其与模拟退火算法的比较 总被引:7,自引:1,他引:6
本文成功地将遗传算法运用于高维衍射位相光学元件的优化设计.并与模拟退火算法进行了比较.结果表明,该算法不仅对于二元,而且对于多元位相光学元件的优化疫计均是十分有效的.而且,它特别适用于利用光电混合处理系统进行优化计算. 相似文献
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JIANG Shaoen XU Yan DING Yongkun LAI Dongxian ZHENG Zhijian HUANG Yixiang LI Jinghong SUN Kexu HU Xin ZHANG Wenhai YI Rongqing CUI Yanli & CHEN Jiusen . National Key Laboratory of Laser Fusion Laser Fusion Research Center Mianyang China . Institute of Applied Physics Computation Mathematics Beijing China 《中国科学G辑(英文版)》2005,48(5):549-558
1 Introduction The investigation of supersonic radiation wave transporting in low density foam pro-duced by thermal radiation is of crucial importance in inertial confinement fusion (ICF) research[1]. When the intense radiation flux is incident in the media, first, a supersonic heat wave is formed which propagates into the undisturbed material. In time, due to the increasing mass of heated material, it slows down and is overtaken by a shock wave,thus becoming of the ablative type. Normally, … 相似文献
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S. V. Pappu 《Optics & Laser Technology》1989,21(5)
A state-of-the-art review on holographic optical elements (HOE) is presented in two parts. In Part I a conceptual overview and an assessment of the current status on the design of HOE have been included. It is pointed out that HOE development based on the use of squeezed light, speckle, non-linear recording, comparative studies between optics and communication approaches, are some of the promising directions for future research in this vital area of photonics. 相似文献