Lens耦合

合集下载

触摸屏coverlens基础知识简介

Coverlens发展历程
初期发展
早期的Coverlens采用简单的玻璃材料，随着技术的发展，逐渐演变为使用聚合物材料。
技术进步
随着触摸屏技术的不断发展，Coverlens也在不断改进，如采用防刮、防指纹、抗蓝光等技术，以满足不同用户的需求。
定制化趋势
目前，Coverlens已经可以根据不同品牌和型号的触摸屏进行定制化生产，以满足不同客户的需求。
的位置。
超声波触摸屏工作原理
超声波发射
超声波触摸屏在屏幕四周安装超声波发射器，向屏幕发射超声波。
超声波反射
当手指触摸屏幕时，会反射部分超声波。
信号检测
通过检测反射回来的超声波信号，可以确定触摸点的位置。
03
Cov特点
光学玻璃
具有高透光率、低折射率、高硬度和低应力等特点，适用于高端产品。
02
Coverlens工作原理
电容式触摸屏工作原理
01
02
03
静电场感应
电容式触摸屏利用静电场感应原理，通过在四角或四边施加电压，使得整个屏幕形成均匀的电场。
手指触摸
当手指触摸屏幕时，由于人体导电性，手指与屏幕之间会形成一个耦合电容。
信号检测
通过检测手指触摸位置的电场变化，可以确定触摸点的位置。
根据产品要求选择合适的材料，并进行裁切、清洗等预处理。
生产加工
采用先进的加工设备对材料进行加工，如切割、研磨、镀膜等。
品质检测
对生产出的Coverlens进行严格的品质检测，确保产品符合要求。
04
Coverlens性能参数与测试方法
Coverlens性能参数指标
透光率

光纤耦合与特性测试实验

目录【实验目的】..................................................................................................... - 2 -【实验原理】..................................................................................................... - 2 -【实验设计】..................................................................................................... - 4 -【思考题】......................................................................................................... - 8 -- 1 -【实验目的】1．了解常用的光源与光纤的耦合方法。

2．熟悉光路调整的基本过程，学习不可见光调整光路的办法。

3．通过耦合过程熟悉Glens 的特性。

4．了解1dB 容差的基本含义。

5．通过实验的比较，体会目前光纤耦合技术的可操作性。

【实验原理】在光纤线路耦合的实施过程中，存在着两个主要的系统问题：即如何从各种类型的发光光源将光功率发射到一根特定的光纤中（相对于目前的光源而言），以及如何将光功率从一根光纤耦合到另外一根光纤中去（相对于目前绝大多数光纤器件而言）。

对于任一光纤系统而言，主要的目的是为了在最低损耗下，引入更多能量进入系统。

这样可以使用较低功率的光源，减少成本和增加可靠度，因为光源是不能工作在接近其最大功率状态的。

光学耦合系统的1dB 失调容差定义为当耦合系统与半导体激光器之间出现轴向、横向、侧向和角向偏移，从而使得耦合效率从最大值下降了1dB 时的位置偏移量。

光器件lens耦合和尾纤耦合需要掌握的知识点

光器件lens耦合和尾纤耦合需要掌握的知识点
光器件lens耦合和尾纤耦合是光学系统的重要部分，也是光学系统的关键技术。

了解光学元件lens耦合和尾纤耦合的原理，可以使我们更好地进行光学系统的设计和维护。

首先，要理解光学元件lens耦合和尾纤耦合，需要知道它们的实际含义。

其中，lens耦合指将光波束从激光器输出聚焦在光纤芯径之间，使光信号透过空气进入光纤尾部而实现耦合的过程。

尾纤耦合是指将光信号聚焦在激光器输出端和光纤芯径之间，以实现光信号的输出的过程。

其次，在lens耦合和尾纤耦合过程中，特别是尾纤耦合过程中，要注意控制空气密度，确保光信号能够发挥最大效率，并不容易受到外界空气分子的干扰。

此外，在光学元件lens 耦合和尾纤耦合过程中还需要知道lens选择和空气影响的原理，以保证所有细节的运行的层次。

总之，了解光学元件lens耦合和尾纤耦合的原理，可以更好地控制光纤系统的运行，同时也有助于提高光学系统的性能。

在使用的过程中，也要注意控制空气密度，选择合适的镜片等，才能确保光学系统的正常运行。

激光与光纤耦合技术

图 2.7 等效接收角与光纤孔径角的关系曲线
柱透镜耦合要求所选用的柱透镜直径要和光纤纤芯直径相当，而且要求激光器、柱透镜、光纤三者的相对位置要极其精确，才能获得较高的耦合效率。 2、自聚焦透镜耦合自聚焦透镜是一种与常规透镜不同的小型透镜，实际上是一段梯度光纤，故又称 GRIN 透镜。自聚焦透镜的聚光能力是依靠折射率的渐变分布实现的，透镜的焦距由透镜的长度决定。因此，自聚焦透镜的加工简单，其端面只需研磨成平面，外形尺寸较小，且数值孔
7
径较大，适用于狭小空间。理想情况下，自聚焦透镜的折射率分布是双曲正割型，因而可以完全消除透镜的球差。但由于制造工艺的影响，很难形成理想的双曲正割型折射率分布，而平端自聚焦透镜的球差仍很严重，会聚光斑较大，采用这种自聚焦透镜的耦合系统的耦合损耗大于 3dB。作为改进，将前端研磨成球面的平凸自聚焦透镜系统可以提高透镜的数值孔径，并补偿折射率分布，从而使耦合损耗降低到 2dB。若对前端的形状进行优化，可以得到 ldB 的耦合损耗。但由于平凸自聚焦透镜系统的优化需要精密的测量手段和复杂的计算，透镜的光学加工需要小曲率球面的精密研磨，这使制造难度和成本增加，因而不适用于批量生产。自聚焦透镜耦合就是首先让激光进入一段自聚焦光纤 (GRIN lens)，即折射率参数为 2 的梯度型折射率光纤，光束强烈的聚焦后，再耦合进光纤中进行传输。自聚焦光纤的折射率在径向的分布符合下式 :
《光纤通信》课程论文
激光与光纤耦合原理与损耗分析
摘要：
本文首先对激光与光纤的耦合方式进行了介绍，对一些耦合方式做了较为详细的分析，并给出了理论表达式与计算结果。其后对耦合的三种机械损耗进行了分析与计算，并给出了分析结果。
关键词：
激光光纤耦合方式损耗分析

光源与光纤耦合实验

课程名称：光纤传感原理与技术实验题目：光源与光纤耦合实验指导教师：班级：学号：学生姓名：一、实验目的和任务1、了解光源与光纤的耦合方法。

2、通过耦合过程熟悉glens或clens的特性。

二、实验仪器及器件1、单模光纤两根2、光纤测试实验箱一台三、实验内容及原理1、所谓光源与光纤耦合是指把光源发出的光功率最大限度地输送到光纤中去。

它涉及到光源辐射空间分布、光源发光面积以及光纤接收光特性和传输特性等。

2、各种透镜耦合（1）薄透镜耦合利用薄透镜成像的原理，把光斑汇集在光纤端面，在数值孔径以内的光能量大部分将耦合到光纤中去，这种方法原理简单，但可操作性，特别是批量生产的可操作性变差，所以目前在生产中逐渐减少。

（2）glens和clensglens和clens是目前使用较多的方案，广泛应用于隔离器、WDM、光开关等等无源器件中。

它的最大优势在于它批量生产中的可操作性，因为它是一个圆柱形的产品，可以直接插入一个精度很高的套筒内，就可以保证其和光路很好的同轴，使生产工艺大大简化。

glens和clens制作准直器的过程：就是把光纤放入毛细管内，点胶，然后切掉端面外的光纤，研磨、抛光、镀膜，再把glens或clens与前面做好的pigtail一起放到一个镀金的圆筒内，整个过程中关键问题是部件的精密配合，以及部件材料和胶的选择。

四、实验步骤1、将650激光器及支架架在导轨的最左侧，连接激光器电源；2、把准直器放入四维调整架的固定孔内，通过光纤准直器数据线将准直器的另一端接到FC接头支架上；3、在FC接头支架后方放置一个白屏；4、打开激光器电源，调节四维调整架，观察白屏上激光器光斑的明暗变化。

五、实验测试数据表格记录图5.1 实验1550nm连接图图5.2 1550nm功率显示图图5.3 实验1310nm连接图图5.4 1310nm功率显示图六、实验结论与感悟（或讨论）做实验之前，首先由上一组同学给我们进行讲解实验箱的功能以及单模光纤和多模光纤，还有实验操作步骤及注意事项。

基于非球面透镜的光纤耦合系统设计

基于非球面透镜的光纤耦合系统设计陈海涛;杨华军;黄小平;程晓洪【摘要】Effectively coupling the coherent laser into single-mode fiber is a key technology for free-space optical communication. In this paper,we analyze how to mitigate the efficiency degradation due to lens spherical aberration and fiber position deviation. Firstly, an aspherical lens was designed to improve the focused spot quality and thereby decrease the coupling loss. Then,a precision fiber holder was adopted to precisely fix the fiber position and make the focal plane of the light coincided with the endface of the fiber. The measured coupling efficiency of 60% is achieved in the experiment.%有效将激光耦合进单模光纤是自由空间光通信的关键技术.为了改善聚焦光束质量和降低耦合损耗,首先设计了消球差非球面透镜,并采用精密光纤支架对耦合光纤进行准确定位使耦合光聚焦在光纤端面上.实验表明,该耦合系统的耦合效率达到60％以上.【期刊名称】《激光与红外》【年(卷),期】2013(043)001【总页数】3页(P76-78)【关键词】光通信;耦合效率;消球差透镜【作者】陈海涛;杨华军;黄小平;程晓洪【作者单位】宜宾学院物理与电子工程学院,四川省高校计算物理重点实验室,四川宜宾644000;电子科技大学物理电子学院,四川成都610054;电子科技大学物理电子学院,四川成都610054;电子科技大学物理电子学院,四川成都610054;宜宾学院物理与电子工程学院,四川省高校计算物理重点实验室,四川宜宾644000【正文语种】中文【中图分类】TN929.111 引言作为一种保密性强且使用灵活的高带宽的通信方式，空间光通信引起人们越来越多的关注［1－5］。

半导体激光器-球透镜-光纤耦合系统分析

图5 目前产品生产中经常遇到TO焦距(光纤耦合极大值位置与TO底座的轴向距离)不稳定的情况，造成耦合效率的不稳定，其主要原因是原材料和生产工艺中的许多不确定性因素，总的来说可归结为l e 的变化和球透镜焦距的变化，而其中 l e 的变化占据主导作用。从理论上，我们希望得到TO焦距量的变化量或者耦合为最大时对应的l f 变化量和l e 的变化量之间的关系，从而在实验过程中能够对问题有更为清楚的认识。按照前面的理论，这种关系似乎比较复杂，而且要经过大量的数值计算，并且不同系统条件下结果也各不相同。但是如果依据图 3 的计算结果作出耦合为最大时l f 随l e 的变化曲线，我们会发现除了绝对值上的差异外，其变化趋势和几何光学的结果 (激光器通过球透镜成理想几何像 )能够较好地相吻合，如图 5 所示，特别是在我们感兴趣的区域，两条曲线的切线斜率非常的相近。这说明，当l e 变化Δl e 时，应用几何光学的公式就能非常方便地得到l f 变化量Δl f 的近似值，即 f 2 ∆l e ∆l f = − (l e − f ) 2 (11)
π ( x 2 + y 2 ) x 2 + y 2 ( x 2 + y 2 )2 φL1 ( x, y ) = − + 1 − 4.l λ .le 8.le e
光场分布为ψ L 2 ( x, y ) ，则变换函数定义为:
L ( x. y ) =
(3)
依据前面的讨论，球透镜用振幅和相位变换函数来描述，设经过球透镜后的激光
图4 实际生产中，我们总是希望系统的耦合效率能够保持稳定或者只在某一范围内变化，从而对l e 、l f 来说希望它们的误差越小越好，但是考虑到原材料和工艺水平，l e 、l f 的误差只能控制在一定范围内，所以我们需要考虑在误差范围内耦合效率的变化是否会超出实际的要求。显然，在相同的误差范围内，耦合效率的变化范围越小，越有利于生产和成品率的提高。假设l e 的误差为±0.02mm，l f 的误差为±0.05mm，考察图 4 所示曲线，图中标出了该误差范围内在各个位置耦合效率可能的变化范围，很明显，在耦合极大值点右侧位置(即过焦)，系统既具有大的耦合效率，同时耦合效率在误差范围内的变化也最小。以此来看，在实际中我们应尽量将l f 选择在此位置。

基于ZEMAX研究微球透镜的耦合效率

---------------------------------------------------------------范文最新推荐------------------------------------------------------ 基于ZEMAX研究微球透镜的耦合效率摘要半导体激光器与光纤耦合技术作为一种重要技术，已经发展到一个比较成熟的阶段，广泛应用于光纤通信、光纤传感等．本文以半导体激光器的光束特性和光纤的传输特性，以及半导体激光器和光纤耦合方式的概括，微球透镜特性的论述为知识基础，基于光学设计软件ZEMAX，在微球透镜的折射率、色散系数，激光器发射光场的参数等条件都确定的情况下，着重分析微球透镜与激光器之间距离的变化对耦合效率的影响。

通过ZEMAX软件模拟分析，可以找出激光源与球透镜表面的距离的最佳位置使得此处会出现所有不同位置的耦合效率的最大值。

关键词半导体激光器微球透镜光纤耦合ZEMAX最大耦合效率7086毕业设计说明书（论文）外文摘要1 / 17TitleResearching the micro-ball lens’coupling efficiency based on ZEMAX.AbstractSemiconductor lasers and fiber coupling technology has developed into a more mature stage as an important technology. And it has been widely used in optical fiber communication, optical fiber sensing and so on.This article is based on the beam characteristics of the semiconductorlaser and fiber transmission, the epitome of semiconductor lasers and fiber-coupled way, and the discussion of micro-ball lens characteristics.Depending on the optical design software, ZEMAX, we analyzed theinfluence of the distance between the micro-ball lens and the laser on the coupling efficiency, in the condition that the refractive index and dispersion---------------------------------------------------------------范文最新推荐------------------------------------------------------coefficient of the micro-ball lens, and the laser emission of light field parameters are identified. By ZEMAX software’s analysis, we can find out the best position to make here be the maximum coupling efficiency of all the different locations of the distance between the laser source and the ball lens surface.2、半导体激光器的光束特性半导体激光器的输出光场分布可以分别用远场和近场特性来描述。

摄像头工作原理

摄像头工作原理：摄像头的工作原理大致为：景物通过镜头(LENS)生成的光学图像投射到图像传感器表面上，然后转为电信号，经过A/D(模数转换)转换后变为数字图像信号，再送到数字信号处理芯片(DSP)中加工处理，再通过USB接口传输到电脑中处理，通过显示器就可以看到图像了。

注1：图像传感器(SENSOR)是一种半导体芯片，其表面包含有几十万到几百万的光电二极管。

光电二极管受到光照射时，就会产生电荷。

注2：数字信号处理芯片DSP(DIGITAL SIGNAL PROCESSING)功能：主要是通过一系列复杂的数学算法运算，对数字图像信号参数进行优化处理，并把处理后的信号通过USB等接口传到PC等设备。

DSP结构框架:1. ISP(image signal processor)(镜像信号处理器)2. JPEG encoder(JPEG图像解码器)3. USB device controller(USB设备控制器)摄像头的构成主要包括主控芯片、感光芯片、镜头和电源。

好的电源也是保证摄像头工作的一个方面。

摄像头镜头：五玻镜头是主流这个问题对于大多数人来说已经不算问题了，笔者提出来也只是仅对小白而言。

简单的说镜头是由透镜组成，摄像头的镜头一般是由玻璃镜片或者塑料镜片组成的。

玻璃镜头能获得比塑料镜头更清晰的影像。

这是因为光线穿过普通玻璃镜片通常只有5%～9%的光损失，而塑料镜片的光损失高达11%～20%。

有些镜头还采用了多层光学镀膜技术，有效减少了光的折射并过滤杂波，提高了通光率，从而获得更清晰影像。

然而，现在很多小厂，为了节约成本、追求高利润，往往减少镜片的数量，或者使用廉价的塑料镜头。

虽然这些产品在价格上便宜不少，看上去很有吸引力，但实际的成像效果却实在是令人无法恭维。

现在市面上大多数摄像头采用的都是五玻镜头，但是不乏少数商家将塑料镜头说成五玻镜头的。

因此消费者在选购一些杂牌摄像头时，一定要详细试用一下，谨防上当受骗。

一种C-LENS透镜耦合安装结构[发明专利]

(19)中华人民共和国国家知识产权局(12)发明专利申请(10)申请公布号 (43)申请公布日 (21)申请号 202010518583.2(22)申请日 2020.06.09(71)申请人无锡爱沃富光电科技有限公司地址 214028 江苏省无锡市硕放振发八路13号(72)发明人阮于华　(74)专利代理机构无锡华源专利商标事务所(普通合伙) 32228代理人聂启新(51)Int.Cl.G02B 6/32(2006.01)G02B 6/26(2006.01)(54)发明名称一种C-LENS透镜耦合安装结构(57)摘要本发明涉及C -LENS透镜耦合技术领域，尤其是一种C -LENS透镜耦合安装结构。

其包括耦合架，所述耦合架安装C -LENS透镜一侧设有圆柱形结构的透镜安装孔，所述透镜安装孔内设有C -LENS透镜，C -LENS透镜外表面和透镜安装孔内表面通过胶水粘结固定；所述耦合架安装光学元件一侧设有耦合孔，耦合孔一端连通透镜安装孔，另一端延伸到耦合架侧端面。

本发明的耦合架采用适当膨胀系数的陶瓷材料制作，尽量减少了C -LENS透镜和耦合架因为热胀冷缩导致的相对安装位置的变化，消除了其他材料的热胀冷缩导致的在温度变化条件下的光传输指标劣化。

权利要求书1页说明书3页附图3页CN 111522100 A 2020.08.11C N 111522100A1.一种C -LENS透镜耦合安装结构，包括耦合架(2)，其特征在于：所述耦合架(2)为圆筒形结构，所述耦合架(2)安装C -LENS透镜(1)一侧设有圆柱形结构的透镜安装孔(4)，所述透镜安装孔(4)内设有C -LENS透镜(1)，所述C -LENS透镜(1)的球面端伸入透镜安装孔(4)中，C -LENS透镜(1)外表面和透镜安装孔(4)内表面通过胶水粘结固定，C -LENS透镜(1)的尾端伸出透镜安装孔(4)；所述耦合架(2)安装光学元件(3)一侧设有耦合孔(5)，耦合孔(5)一端连通透镜安装孔(4)，另一端延伸到耦合架(2)侧端面；所述耦合架(2)背向C -LENS透镜(1)一侧端面通过胶水粘结光学元件(3)，光学元件(3)能够完全覆盖耦合孔(5)；所述C -LENS透镜(1)、耦合架(2)和光学元件(3)的中心位于同一轴线上。

一种C-lens透镜组件[实用新型专利]

(10)授权公告号 (45)授权公告日 2015.01.28C N 204129304U (21)申请号 201420552219.8(22)申请日 2014.09.24G02B 7/02(2006.01)G02B 6/32(2006.01)(73)专利权人广州隆润光学仪器有限公司地址510760 广东省广州市经济技术开发区东区笔岗大路39号12栋3楼(72)发明人范卫星(74)专利代理机构广州嘉权专利商标事务所有限公司 44205代理人郑莹(54)实用新型名称一种C-lens 透镜组件(57)摘要本实用新型公开了一种C-lens 透镜组件，包括套管和装在所述套管内的C-lens 透镜，所述套管和C-lens 透镜通过胶水固定粘结，所述C-lens透镜包括圆柱状的透镜本体，所述透镜本体的一端形成倾斜于所述透镜本体轴线的斜端面，另一端形成球面，环绕所述斜端面的外缘设有内凹的容胶位。

本C-lens 透镜组件中，环绕所述斜端面的外缘设有内凹的容胶位，容胶位可设置为台阶或锥面，C-lens 透镜与套管通过胶水粘合后，过剩的从胶水由斜端面的外缘溢出，并汇集在台阶或锥面内，从而避免渗流到C-lens 透镜两个端面上，保证C-lens 透镜的透光性以及与后侧光纤的光学耦合定位，降低整个组件的光损。

此外，通过上述结构改进，也减少了装配过程中的人工消耗，为快速实现组件装配以及提高产线良率提供可能。

(51)Int.Cl.权利要求书1页说明书2页附图2页(19)中华人民共和国国家知识产权局(12)实用新型专利权利要求书1页说明书2页附图2页(10)授权公告号CN 204129304 U1.一种C-lens透镜组件，其特征在于：包括套管和装在所述套管内的C-lens透镜，所述套管和C-lens透镜通过胶水固定粘结，所述C-lens透镜包括圆柱状的透镜本体，所述透镜本体的一端形成倾斜于所述透镜本体轴线的斜端面，另一端形成球面，环绕所述斜端面的外缘设有内凹的容胶位。

微带耦合器的中英文对照翻译

微带耦合器的中英文对照翻译Design and Analysis of Wideband Nonuniform Branch Line Coupler and Its Application in a Wideband Butler MatrixYuli K. Ningsih,1,2 M. Asvial,1 and E. T. RahardjoAntenna Propagation and Microwave Research Group (AMRG), Department of Electrical Engineering, Universitas Indonesia, New Campus UI, West Java, Depok 16424, Indonesia Department of Electrical Engineering, Trisakti University, Kyai Tapa, Grogol, West Jakarta 11440, IndonesiaReceived 10 August 2011; Accepted 2 December 2011Academic Editor: Tayeb A. DenwdnyCopyright ? 2012 Yuli K. Ningsih et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.AbstractThis paper presents a novel wideband nonuniform branch line coupler. An exponential impedance taper is inserted, at the series arms of the branch line coupler, to enhance the bandwidth. The behavior of the nonuniform coupler was mathematically analyzed, and its design of scattering matrix was derived. For a return loss better than 10?dB, itachieved 61.1% bandwidth centered at 9GHz. Measured coupling magnitudes and phase exhibit good dispersive characteristic. For the 1dB magnitude difference and phase error within 3°, it achieved 22.2% bandwidth centered at 9GHz. Furthermore, the novel branch line coupler was implemented for a wideband crossover. Crossover was constructed by cascading two wideband nonuniform branch line couplers. These components were employed to design a wideband Butler Matrix working at 9.4GHz. The measurement results show that the reflection coefficient between the output ports is better than 18dB across 8.0GHz–9.6GHz, and the overall phase error is less than 7.1. IntroductionRecently, a switched-beam antenna system has been widely used in numerous applications, such as in mobile communication system, satellite system, and modern multifunction radar. This is due to the ability of the switched-beam antenna to decrease the interference and to improve the quality of transmission and also to increase gain and diversity.The switched-beam system consists of a multibeam switching network and antenna array. The principle of a switched-beam is based on feeding a signal into an array of antenna with equal power and phase difference. Different structures of multibeam switching networks have been proposed, such as the Blass Matrix, the Nolen Matrix, the RotmanLens, and the Butler Matrix .One of the most widely known multibeam switching networks with a linear antenna is the Butler Matrix. Indeed, it seems to be the most attractive option due to its design simplicity and low power loss .In general, the Butler Matrix is an N × N passive feeding network, composed of branch line coupler, crossover, and phase shifter. The bandwidth of the Butler Matrix is greatly dependent on the performance of the components. However, the Butler Matrix has a narrow bandwidth characteristic due to branch line coupler and crossover has a limited bandwidth. As there is an increased demand to provide high data throughput , it is essential that the Butler Matrix has to operate over a wide frequency band when used for angle diversity. Therefore, many papers have reported for the bandwidth enhancement of branch line coupler . In reference , design and realization of branch line coupler on multilayer microstrip structure was reported. These designs can achieve a wideband characteristic. However, the disadvantages of these designs are large in dimension and bulk.Reference introduces a compact coupler in an N-sectiontandem-connected structure. The design resulted in a wide bandwidth. Another design, two elliptically shaped microstrip lines which are broadside coupled through an elliptically shaped slot, was employed in . This design was used in a UWB coupler with high return loss andisolation. However, these designs require a more complex manufacturing.In this paper, nonuniform branch line coupler using exponential impedance taper is proposed which can enhance bandwidth and can be implemented for Butler Matrix, as shown in Figure1. Moreover, it is a simple design without needs of using multilayer technology. This will lead in cost reduction and in design simplification.Figure 1:Geometry structure of a new nonuniform branch line coupler design with exponential impedance taper at the series arm.To design the new branch line coupler, firstly, the series arm’s impedance is modified. The shunt arm remains unchanged. Reduced of the width of the transmission line at this arm is desired by modifying the series arm. Next, by exponential impedance taper at the series arm, a good match over a high frequency can be achieved.2. Mathematical Analysis of Nonuniform Branch Line CouplerThe proposed nonuniform branch line coupler use λ/4 branches with impedance of 50Ω at the shunt arms and use the exponential impedance taper at the series arms, as shown in Figure1. Since branch line coupler has a symmetric structure, theeven-odd mode theory can be employed to analyze the nonuniform characteristics. The four ports can be simplified to a two-port problem in which the even and odd mode signals are fed to two collinear inputs [22].Figure 2 shows the schematic of circuit the nonuniform branch line coupiers.Figure 2:Circuit of the nonuniform branch line coupler.The circuit of Figure 2 can be decomposed into the superposition of an even-mode excitation and an odd-mode excitation is shown in Figures and .Figure 3:Decomposition of the nonuniform branch line coupler into even and odd modes of excitation.The ABCD matrices of each mode can be expressed following . In the case of nonuniform branch line coupler, the matrices for the even and odd modes become:A branch line coupler has been designed based on the theory of small reflection, by the continuously tapered line with exponential tapers , as indicated in Figure 1, wherewhich determines the constant as:Useful conversions for two-port network parameters for the even and odd modes of S11 and S21 can be defined as follows :whereSince the amplitude of the incident waves for these two ports are ±1/2, the amplitudes of the emerging wave at each port of the nonuniform branch line coupler can be expressed asParameters even and odd modes of S11 nonuniform branch linecoupler can be expressed as and as follows:An ideal branch line coupler is designedto have zero reflection power and splits the input power in port 1 (P1) into equal powers in port 3 (P3) and port 4 (P4). Considering to , a number of properties of the ideal branch line coupler maybe deduced from the symmetry and unitary properties of its scattering matrix. If the series and shunt arm are one-quarter wavelength, by using , resulted in S11 = 0.As both the even and odd modes of S11 are 0, the values of S11 and S21 are also 0. The magnitude of the signal at the coupled port is then the same as that of the input port.Calculating and under the same , the even and odd modes ofS21 nonuniform branch line coupler will be expressed as follows in Based on ,S11 can be expressed as follows Following ,S41 nonuniform branch line coupler can be calculating as followsFrom this result, both S31 and S41 nonuniform branch line couplers have equal magnitudes of ?3dB. Therefore, due to symmetry property, we also have thatS11=S22=S33=S44=0,S13=S31，S14=S41，S21=S34, and . Therefore, the nonuniform branch line coupler has the following scattering matrix in3. Fabrication and Measurement Result of Wideband Nonuniform Branch Line CouplerTo verify the equation, the nonuniform branch line coupler was implemented and its -parameter was measured. It was integrated on TLY substrate, which has a thickness of 1.57mm. Figure 4 shows a photograph of a wideband nonuniform branch line coupler. Each branch at the series arm comprises an exponentially tapered microstrip line which transforms the impedance from ohms to ohms. This impedance transformation has been designed across a discrete step length mm.Figure 4:Photograph of a proposed nonuniform branch line coupler.Figure 5 shows the measured result frequency response of the novel nonuniform branch line coupler. For a return loss and isolation better than 10dB, it has a bandwidth of about 61.1%; it extends from 7 to 12.5GHz. In this bandwidth, the coupling ratio varies between 2.6?dB up to 5.1dB. If the coupling ratio is supposed approximately 3 ± 1dB, the bandwidth of about 22.2% centered at 9GHz.Figure 5:Measurement result for nonuniform branch line coupler.As expected, the phase difference between port 3 (P3) and port 4 (P4) is 90°. At 9?GHz, the phases of and are 85.54° and 171°, respectively. These values differ from ideal value by4.54°. The average phase error or phase unbalance between two branch line coupler outputs is about 3°. But even the phase varies with frequency; the phase difference is almost constant and very close toideal value of 90° as shown in Figure 6.Figure 6:Phase characteristic of nonuniform branch line coupler.4. Design and Fabrication of the Wideband Butler MatrixFigure 7 shows the basic schematic of the Butler Matrix . Crossover also known as 0dB couplers is a four-port device and must provide for a very good matching and isolation, while the transmitted signal should not be affected. In order to achieve wideband characteristic crossover, this paper proposes the cascade of two nonuniform branch line couplers.Figure 7:Basic schematic of the Butler Matrix .Figure 8 shows the microstrip layout of the optimized crossover. The crossover has a frequency bandwidth of 1.3GHz with VSWR = 2, which is about 22.2% of its centre frequency at 9?GHz. Thus, it is clear from these results that a nonuniform crossover fulfills most of the required specifications, as shown in Figure 9.Figure 8:Photograph of microstrip nonuniform crossover.Figure 9:Measurement result for nonuniform crossover.Figure 10 shows the layout of the proposed wideband Butler Matrix. This matrix uses wideband nonuniform branch line coupler, wideband nonuniform crossover, and phase-shift transmission lines.Figure 10:Final layout of the proposed wideband Butler Matrix .The wideband Butler Matrix was measured using Network Analyzer.Figure 11 shows thesimulation and measurement results of insertion loss when a signal was fed into port 1, port 2, port 3, and port 4, respectively. The insertion loss are varies between 5dB up to 10dB. For the ideal Butler matrix, it should be better than 6dB. Imperfection of fabrication could contribute to reduction of the insertion loss.Figure 11:Insertion loss of the proposed Butler Matrix when different ports are fed. The simulated and measured results of the return loss at each port of the widedend Butler Matrix is shown in Figure 12. For a return loss better than 10dB, it has a bandwidth about 17% centered at 9.4GHz.Figure 12:Return loss of the proposed Butler Matrix when different ports are fed.Figure 13 shows the phase difference of measured results when a signal was fed into port 1, port 2, port 3, and port 4, respectively. The overall phase error was less than 7°. There are several possible reasons for this phase error. A lot of bends in high frequency can produce phase error. Moreover, the imperfection of soldering, etching, alignment, and fastening also could contribute to deviation of the phase error.Figure 13:Phase difference of the proposed Butler Matrix when different ports are fed. Table 1 shows that each input port was resulted a specific linear phase at the output ports. The phase differences eachbetween the output ports are of the same value. The phase difference can generate a different beam ( θ). If port 1 (P1) is excited, the phase difference was 45°, the direction of generated beam ( θ) will be 14.4° for 1L. It is summarized in Table 1.Table 1:Output phase difference and estimated direction of generated beam.5. ConclusionA novel nonuniform branch line coupler has been employed to achieve a wideband characteristic by exponential impedance taper technique. It is a simple design without needs of using multilayer technology and this will lead to cost reduction and design simplification. The scattering matrix of the nonuniform branch line coupler was derived and it was proved that the nonuniform branch line coupler has equal magnitude of ?3dB. Moreover, the novel nonuniform branch line coupler has been employed to achieve a wideband 0dB crossover. Furthermore, these components have been implemented in the Butler Matrix and that achieves wideband characteristics.References? T. A. Denidni and T. E. Libar, “Wide band four-port butler matrix for switched multibeam antenna array s,” in Proceedings of the IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC '03), vol. 3, pp. 2461–2464, 2003. View atPublisher ·View at Google Scholar? E. Siachalou, E. Vafiadis, S. S. Goudos, T. Samaras, C. S. Koukourlis, and S. Panas, “On the design of switched-beam wideband base stations,” IEEE Antennas and Propagation Magazine, vol. 46, no. 1, pp. 158–167, 2004. View at Publisher ·View at Google Scholar ·View at Scopus ? P. S. Hall and S. J. Vetterlei n, “Review of radio frequency beamforming techniques for scanned and multiple beam antennas,” IEE Proceedings H, vol. 137, no. 5, pp. 293–303, 1990. View at Scopus ?? W-D. Wirth, Radar Techniques Using Array Anney, IEE Publishers, Stevenage, UK, 2001. S. Y. Zheng, S. H. Yeung, W. S. Chan, and K. F. Man, “Broadband butler matrix optimized using jumping genes evolutionary algorithm,” in Proceedings of the IEEE International Conference on Industrial Technology (IEEE ICIT '08), Hong Kong, April 2008. Viewat Publisher ·View at Google Scholar? K. Wincza and K. Sachse, “Broadband Butler matrix in microstrip multilayer technology designed with the use of three-section directional couplers and phase correction Networks,” in Proceedings of the 18th International Conference on Microwave Radar and Wireless Communications(MIKON '10), Cracow, Poland, June 2010.? A. M. El Tager and M. A. Eleiwa, “Design and implementation of a smart antenna using butler matrix for ISM band,” in Proceedings of th eProgress in Electromagnetics Research Symposium (PIERS '09), pp. 571–575, Beijing, China, March 2009.? Y. S. Jeong and T. W. Kim, “Design and analysis of swapped port coupler and its application in a miniaturized butler matrix,” IEEE Transactions on Microwave Theory and Techniques, vol. 58, no. 4, pp. 764–770, 2010. View at Publisher ·View at Google Scholar ·View at Scopus? C. Collado, A. Grau, and F. De Flaviis, “Dual-band butler matrix for WLAN systems,” in IEEE MTT-S International Microwave Symposium Digest, vol. 2005, pp. 2247–2250, 2009. View at Publisher ·View at Google Scholar?? K. Wincza, S. Gruszczynski, and K. Sachse, “Integrated four-beam dual-band antenna array fed by broadband Butler matrix,” Electronics Letters, vol. 43, no. 1, pp. 7–8, 2007. View at Publisher ·View at Google Scholar ·View at Scopus?? T. N. Kaifas and J. N. Sahalos, “On the design of a single-layer wideband Butler matrix for switched-beam UMTS system applications,” IEEE Antennas and Propagation Magazine, vol. 48, no. 6, pp. 193–204, 2006. View at Publisher ·View at Google Scholar ·View at Scopus ?? K. Wincza and S. Gruszczynski, “A broadband 4 × 4 butler matrix for modern-day antennas,” in Proceedings of the 35th European Microwave Conference, pp. 1331–1334, Paris, France, October 2005.View at Publisher ·View at Google Scholar?? S. Gruszczyoski, K. Wincza, and K. Sachse, “Reduced sidelobefour-beam N-element antenna arrays fed by 4 × 4 N butler matrices,” IEEE Antennas and Wireless PropagationLetters, vol. 5, no. 1, pp. 430–434, 2006. View at Publisher ·View at Google Scholar ·View at Scopus?? Y. C. Su, M. E. Bialkowski, F. C. E. Tsai, and K. H. Cheng, “UWB switched-beam array antenna employing UWB butler matrix,” in Proceedings of the IEEE International Workshop on Antenna Technology: Small Antennas and Novel Metamaterials (iWAT '08), pp. 199–202, Hsinchu, Taiwan, March 2008. View at Publisher ·View at Google Scholar ?? J. He, B. Z. Wang, Q. Q. He, Y. X. Xing, and Z. L. Yin, “Wi debandx-band microstrip Butler matrix,” Progress in Electromagnetics Research, vol. 74, pp. 131–140, 2007. View at Scopus?? Y. Liuqing and G. B. Giannakis, “Ultra wideband communications,” IEEE Signal Processing Magazine, vol. 21, no. 6, pp. 26–54, 2004. View at Publisher ·View at Google Scholar ·View at Scopus?? S. Banba and H. Ogawa, “Multilayer MMIC directional c ouplers using thin dielectric layers,” IEEE Transactions on Microwave Theory and Techniques, vol. 43, no. 6, pp. 1270–1275, 1995. View at Publisher ·View at Google Scholar ·View at Scopus?? J. Sebastien and G. Y. Delisle, “Microstrip EHF butler matrixdesign and realization,” ETRI Journal, vol. 27, no. 6, pp. 788–797, 2005. View at Scopus?? J. H. Cho, H. Y. Hwang, and S. W. Yun, “A design of wideband 3-dB coupler with N-section microstrip tandem structure,” IEEE Microwave and Wireless Components Letters, vol. 15, no. 2, pp. 113–115, 2005. View at Publisher ·View at Google Scholar ·View at Scopus ?? M. E. Bialkowski, N. Seman, and M. S. Leong, “Design of a compact ultra wideband 3? db microstrip-slot coupler with high return losses and isolation,” i n Asia Pacific Microwave Conference (APMC '09), pp. 1334–1337, St. Lucia, Australia, December 2009. View at Publisher ·View at Google Scholar?? R. P. Hecken, “A near-optimum matching section without discontinuities,” IEEETransactions on Microwave Theory and Techniques, vol. 20, no. 11, pp. 734–739, 1972. ?? D. M. Pozar, Microwave Engineering, John Wiley& Sons, New York, NY, USA, 2nd edition, 1998.?? M. Bona, L. Manholm, J. P. Starski, and B. Svensson, “Low loss compact butler matrix for a microstrip antenna,” IEEE Transactions on Microwave Theory and Techniques, vol. 50, no. 9, pp. 2069–2075, 2002. View at Publisher ·View at Google Scholar?? M. Kobayashi and N. Sawada, “Analysis and synthesis of tapered microstriptransmissio n lines,” IEEE Transactions on Microwave Theory and Techniques, vol. 40, no. 8, pp. 1642–1646, 1992. View at Publisher ·View at Google Scholar宽带非均匀支线耦合器及其应用在宽带巴特勒矩阵的设计与分析协作院校：印尼大学新校区电机工程学系天线传播和微波研究小组（AMRG）。

激光与光纤耦合技术

（2.6）
自聚焦透镜的焦距 f 为 :
8
f =
1 n0 g sin( gL)
（2.7）
L 为透镜长度， g 为聚焦常数。当自聚焦光纤长度 L 为四分之一正弦波周期的奇数倍时(正弦波周期 f=1/n0 g，透镜的聚焦能力最强;当 L 为四分之一正弦波周期的偶数倍时, 自聚焦光纤焦距为无穷大，没有聚焦作用。 3、组合透镜耦合最初的组合透镜耦合系统都是由多片常规透镜组合而成，由于进行了消球差和光束整形设计，可以获得较低的耦合损耗。但其受到光学加工水平的限制，外形尺寸较大，无法满足微型化的要求。当前的组合透镜一般由微球透镜和自聚焦透镜组合而成。为了进一步降低耦合损耗，可将自聚焦透镜直接连在光纤端面，构成虚光纤结构。这种结构可以大大提高 1dB 失调容差，并获得较低的耦合损耗。未加增透膜的情况下，耦合损耗达到 3dB，加增透膜情况下，达到 2dB。几种典型系统结构如图 2.9 所示。
图 1. 1 光纤耦合的耦合条件
激光束的光束参数乘积（BBP）定义为：
BBP = Dlaser θlaser 4
(1.3)
根据赫姆霍兹不变量，在没有像差和光阑的情况下，对于一束激光来说光束参数乘积是一个固定值，即光束参数乘积不会因为光学系统的改变而改变。从公式(1.1)、(1.2)、(1.3) 可以推出:
(2.2)
圆锥形微透镜光纤的数值孔径和平端光纤数值孔径之间满足下列关系 : sin θ c' sin γ 1 sin γ 1 sin γ 2 sin γ 3 sin γ n −1 = = ...... sin θ c sin γ n sin γ 2 sin γ 3 sin γ 4 sin γ n
图 2.3 球透镜端面耦合中光纤参数与等效接收角关系

有关LENS的一些基本知识

调制传递函数(MTF)一）MTF 的定义：MTF 调制度=最大亮度-最小亮度/最大亮度+最小亮度景物有景物的调制度(M 景)，影像有影像的调制度(M 影)理想的Lens 系统的MTF 值为1, 但由于实际的Lens 系统中各种像差的存在及介质的吸收等作用，都会使MTF 产生较大的衷减．二）MTF 的意义及作用在Lens 系统中，MTF 是对Lens 系统的总体评价参数．在设计阶段，可通过相关的光学设计软件对所设计的Lens 进行模拟；在制造阶段，可以对Lens 实体进行MTF 的测试．故在当今的光学领域ＭTF 有着极其广泛的应用三）MTF 特性1.在MTF 曲线中，当空间频率为零时，其MTF 值为为１，而之后随着空间频率的增加而下降，当降至一定程度时，人眼或其它感光组件就无法对其进行分辨．注：人眼对MTF 的极限分辨值为0.07（或0.05）。

于此值时人眼已无法分辨其对比度。

2.斜向入射时，通常都会根据斜向角度的轴分为径向(Saggital)和切向(Tangental)通常简写为S 和T 方向，而这两个方向的MTF 值会不同，就一般而言，S 的MTF 值会优于T 的MTF 值五）光学玻璃为传统常用的主要光学材料，一般的光学玻璃的光波透明范围为350nm~2500nm, 在低于400nm时已开始中显示对光的强烈吸收。

其分类主要有冕牌及火石两大系列。

光学晶体也是一种较常用的光学材料，如在光学仪器及光通信组件中均有较多的应用。

有些光学晶体的波带很宽，且性能特异，可以应用到红外或紫外等特殊场合。

另，很多晶体具有双折射的性质，可以用来制造偏振组件。

光学塑胶材料常用的主要有PMMA(压克力)、ＰＣ（聚碳酸脂）等材料，塑胶光学组件可以用注射成形的方法,生产效率高且成本低,特别是一些具有非球面的光学组件,如果要靠传统的研磨加工方法则成本很高且效率很低,故民用的非球面光学组件大部分为塑胶成形而得。

镀膜材料在Lens系统中，有时为了达到一定的功能或效果需在组件表面上加镀不同的膜层。

半导体激光器光纤耦合设计

半导体激光器光纤耦合设计战利伟;高欣;薄报学;计光【摘要】由于半导体激光器本身存在固有的缺陷:在平行于p-n结方向(慢轴方向)和垂直于p-n结方向(快轴方向)的发散角不同,这样就限制了其在许多领域的应用.在对半导体激光器光束进行深入的分析后,本文提出利用一种双曲面透镜来对半导体激光器所发出的光束进行多模光纤耦合仿真,结果可以得到87.652%的耦合效率.【期刊名称】《长春理工大学学报（自然科学版）》【年(卷),期】2011(034)002【总页数】2页(P54-55)【关键词】半导体激光器;发散角;光纤耦合【作者】战利伟;高欣;薄报学;计光【作者单位】长春理工大学高功率半导体激光国家重点实验室,长春130022;长春理工大学高功率半导体激光国家重点实验室,长春130022;长春理工大学高功率半导体激光国家重点实验室,长春130022;长春理工大学高功率半导体激光国家重点实验室,长春130022【正文语种】中文【中图分类】TN248随着光电子技术的快速发展，半导体激光器在生产、生活方面有着广泛的应用。

半导体激光器具有效率高、体积小、可靠性好等优点，使得半导体激光器在许多行业凸显出优势。

但由于半导体激光器自己结构的特点，其输出光束在垂直于结平面和平行于结平面方向的发散角不同，尤其是垂直于结平面方向(快轴方向)具有很大的发散角。

目前对于半导体激光器光束整形的方法中，光纤耦合普遍被人们所接收，通过这种方法既可以实现光束的灵活传输，也为使用带来了方便。

在具体分析半导体激光器输出光束特点情况下，本文提出了可以对 LD输出光束的快轴和慢轴同时准直并且两面具有不同曲率半径的微透镜，通过ZEMAX软件进行仿真，能够得到较高的耦合效率。

这种透镜具有结构简单、调整方便、耦合效率高的特点。

双曲面透镜的外形尺寸(L×W×T)为2mm×2mm×1mm，快、慢轴的有效焦距(effective focus length)分别为 0.072mm、0.472mm。