共查询到20条相似文献,搜索用时 218 毫秒
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文章设计了平面透镜、单凸透镜、双凸透镜组及格林透镜等几种光学窗口,并通过发火试验详细讨论了几种窗口的优劣。研究结果表明,自聚焦透镜发火阈值要远低于其它光学透镜结构发火能量,是目前最为理想的窗口透镜。 相似文献
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研究了自聚焦透镜及其列阵象平面上的照度分布。讨论只限于近轴射线单位放大率成象的条件下。一列和二列的自聚焦透镜列阵在场扫描和线扫描光学成象系统中,象面上光强分布将有所不同。因此,我们作了分析,并对某些样品进行了测量。 相似文献
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在线性光学范畴下,光学超构材料等人工结构材料的出现与发展使得人们在控制光与物质的相互作用方面拥有更多自由度。例如,利用人工设计的功能单元可在亚波长尺度对光的振幅、相位和偏振进行灵活有效的调控,从而实现超透镜、负折射、隐身衣等新奇光学效应。通过调控超构材料中光的几何相位、局域电磁增强等物理机制,可实现光与物质相互作用的显著增强,为实现非线性微纳光学光源及其应用开启了新的大门。围绕近年来光学超构材料在光学频率转换、超快光开关与光调制、以及非线性相位调控等方面的研究进展进行了总结,并对非线性光学超构材料在未来应用中的前景和所面临的挑战进行了展望。 相似文献
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本文给出了四层媒质理论模型中有两层具有光吸收特性时,各层媒质中两维交变温度场的严格解,并由此导出目前光声检测中常用的传声器检测,光热光偏转检测,热透镜、光热光位移检测、光声压电和热释电检测中先声信号的理论表达式,使固体光学检测理论更系统化和实用化。 相似文献
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用于毫米波焦面阵成像系统的扩展半球介质透镜 总被引:2,自引:0,他引:2
毫米波成像是近年来毫米波领域的一个研究热点,而焦面阵成像因其具有实时成像的优点更加受到重视。中分析可用为面阵成像的扩展半球介质透镜。这种焦面阵成像结构将集成天线阵贴附在透镜背面接收透镜聚焦的功率,消除了集成天线工作在毫米波频段时存在的表面波对天线性的影响,具有尺寸紧凑、损耗小的特点。采用Stratton-Chu公式和射线追迹分析了电磁波入射到扩展半球透镜上时在其背面的场分布,即透镜的焦区场分布,以获得透镜用于焦面阵成像时的性能。为验证分析方法的正确性,对平面波垂直入射和会聚高斯束入射两种情形进行了实验验证,实验结果与理论分析吻合较好。该透镜天线还可用来消除常规集成毫米波系统中抛物面天线与集成前端之间的过渡,以降低损耗,改善系统性能,也可用于与准光系统的连接或耦合。该结果将对上述应用提供理论指导。 相似文献
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四通道单模光纤旋转连接器的研制 总被引:1,自引:0,他引:1
设计了一种基于道威棱镜的光传输特性的四通道单模光纤旋转连接器,采用锥齿轮行星轮结构实现光信号的旋转耦合,并设计了耦合调整方案;分析道威棱镜光轴与旋转轴不重合带来的耦合损耗,确定道威棱镜的装调精度。最终使四通道单模光纤旋转连接器的技术指标达到了国外同类产品水平,且道威棱镜的通光孔径大,可在结构尺寸不变的情况下直接扩展为八通道单模光纤旋转连接器。 相似文献
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A new type of diffractive optical bar code produced by computer-generated holographic technology is proposed. The message in the proposed bar code is hidden in the diffracted light of the bar code element and can be read from the first diffraction order. In contrast to the conventional hidden bar code, which needs a lens to focus the diffracted light, the proposed hidden bar code has a property of self-focusing. This self-focusing ability is achieved by modulating a function of the Fresnel zone plate into the bar code format. Consequently, the read-out process for the information in this hidden bar code avoids the use of a lens. Experiments have shown the feasibility of the proposed bar code and confirmed that it can perform better than the conventional hidden bar code. 相似文献
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聚合物光纤网络器件及其通信链路系统 总被引:2,自引:1,他引:1
通过自行研制的聚合物光纤波长转换器和集线器,实现了石英光纤传输介质到聚合物光纤传输介质的工作波长转换,以及多路聚合物光纤传输信息的交换和局域网信息的全聚合物光纤传输。系统测试结果显示,数据交换传输速率达到100Mbps,通信眼图清晰。链路系统传输信号随传输距离成指数衰减,与聚合物光纤的光强衰减规律一致。用商用的发射接收器测得传输距离达到60m以上。聚合物光纤弯曲半径为25mm时,给系统接收端接收信号强度带来0.1~0.4dB的衰减,表明聚合物光纤弯曲对链路系统工作影响较小。 相似文献
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Fabrication method and device of ultra-small gradient-index(GRIN) fiber probe were investigated in order to explore the development of ultra-small probes for optical coherence tomography(OCT) imaging.The beamexpanding effect of no-core fiber(NCF) and the focusing properties of the GRIN fiber lens were analyzed based on the model of GRIN fiber probe consisting of single-mode fiber(SMF),NCF and GRIN fiber lens.A stereo microscope based system was developed to fabricate the GRIN fiber probe.A fiber fusion splicer and an ultrasonic cleaver were used to weld and cut the fiber respectively.A confocal microscopy was used to measure the dimensions of probe components.The results show that the sizes of probe components developed are at the level of millimeter.Therefore,the proposed experimental system meets the fabrication requirements of an ultra-small self-focusing GRIN fiber probe.This shows that this fabrication device and method can be employed in the fabrication of ultrasmall self-focusing GRIN fiber probe and applied in the study of miniaturized optical probes and OCT systems. 相似文献
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Experimental study of a model digital space optical communication system with new quantum devices 总被引:1,自引:0,他引:1
Junxiong T Qingji W Yimin L Liang Z Jianhua G Minghao D Jiankun K Lemin Z 《Applied optics》1995,34(15):2619-2622
We report a digital space optical communication system with new features both in the transmitting and in the receiving ends. The diode laser source is stabilized to within ±100 kHz by locking its frequency to the transmission peak of a Faraday anomalous dispersion optical filter (FADOF). The optical filter in the receiver uses two FADOF's that are linked to eliminate the multipeak structure and achieve a single-peak bandwidth of ~1 GHz. The detection sensitivity of this system is 23 times higher than that of a system with a traditional interference filter. 相似文献
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研制了可对一维高温温度场进行测量的扫描式高温计.该扫描式高温计分为旋转扫描式光学系统、比色高温计和上位机三个部分.在分析温度场测量要求的基础上,推导了比色光学高温计的测量原理,建立了数学模型.基于光的反射理论,研究了旋转扫描式光学系统与一维温度场之间的运动关系.利用光学光纤将光学探头接收的光信号进行远距离传输,增加了测量的便利性和整套装置对测量环境的适应能力,专用的微型工控及控制系统提高了这套装置独立工作及与其他设备进行协调合作的能力.对比色高温计的波长函数和测量精度进行了标定,校验结果表明在800℃~3500℃范围内的测量精度为1%.最后,利用扫描式高温计对棒状碳/碳试样的轴向温度场进行了测量,通过几个固定点温度对一维温度场的测量精度进行了校验,最大测量误差为3.09%. 相似文献
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Barton IM Britten JA Dixit SN Summers LJ Thomas IM Rushford MC Lu K Hyde RA Perry MD 《Applied optics》2001,40(4):447-451
We describe the advantages of using diffractive (Fresnel) lenses on thin membranes over conventional optics for, among others, future space telescope projects. Fabrication methods are presented for lenses on two types of freestanding membrane up to 50 cm in size. The first is a Fresnel lens etched into a thin (380-mum) glass sheet, and the second is an ~50-mum-thick polymer membrane containing a Fresnel lens made by replication process from a specially made fused-silica master. We show optical performance analysis of all the lenses that are fabricated, including a diffraction-limited Airy spot from a 20-m- focal-length membrane lens in a diffractive telescope system. 相似文献