新型矿用激光指向仪的设计

在新型矿用激光指向仪的设计过程中,根据仪器设计指标要求,首先采用新型半导体激光器、倒置的高倍率望远系统,设计了激光指向仪准直光路系统,利用双透镜望远准直系统将半导体激光器发出的椭圆形高斯光束进行整形,提高准直精度。然后利用Pro/E软件对壳体组、镜筒组等部件进行了三维机械设计。设计结果表明,仪器结构合理,外形美观,小型轻便。最后,对激光指向仪的误差源进行了理论分析和计算,理论分析与实测数据基本相符,满足设计要求。     

LD准直透镜光能耦合效率与波差的理论分析

ＬＤ准直透镜光能耦合效率与波差的理论分析陈海清，阮玉，常洋燕（华中理工大学）０引言激光二级管发射的光束是发散的，需经过椭圆光束准直，整形及象散校正，从而获得发散度小准直度高的光束，同时还要考虑系统的光能利用效率与波差问题。准直透镜的作用是把ＬＤ所发出...     

一种线宽可调的激光标线仪

详细介绍了利用柱透镜准直的激光标线原理.激光标线仪的主要性能指标之一激光线的弯曲度,对激光标线的弯曲度误差作了分析,得出了激光光源和柱透镜的位置关系是影响弯曲度主要因素.为保证圆柱透镜和投射激光束的位置关系在正透镜调整圈端部设计一个定位柱面,和镜筒内孔的圆柱面相配合,保证了正透镜调整圈和镜筒的同轴度,一般的结构是镜调整...     

微型透镜元件的最新动向

一、前言微型透镜元件在光通信领域中的应用最初是作为半导体激光器与光纤耦合的耦合透镜而发展起来的。最近,随着光盘等在信息记录再现领域中的应用迅速扩展,物镜和准直透镜作为光敏元件开始得到大量使用。因此,     

飞秒激光直写加工柱面微透镜阵列的方法研究

正柱面微透镜阵列在叠阵半导体激光器快慢轴准直、裸眼3D成像、平行加工等领域有着广泛应用。针对半导体激光器领域:随着输出功率增大,尺度缩小;用于准直的透镜单元宽度由目前500μm朝100μm内缩减,长度维持mm量级,基材朝石英玻璃等高强度材料发展。目前适用于单元宽度100μm以内透镜阵列制造的方法均受限于聚合物材料,且受占空比小、效率低等缺陷影响,均难以满足工业发展需求。飞秒激光以其超快、超强的独特优势,可对所有材料实现冷加工,且加工尺     

利用半导体激光束实现激光隧道放样研究

提出了一种利用半导体激光器实现隧道激光扫描放样的方法 ,该方法满足了放样仪器需轻巧、便于携带的要求。其中用单透镜准直法对有大发散角的半导体激光光束成功地实现了准直 ,既简单又经济实用 ;用平移物镜法实现了激光点的扫描。理论分析和实验结果都证明这一放样方法是可行的     

光纤传感测量中耦合系统的设计

根据光纤传感测量中光源的选取原则,将半导体激光器作为光纤传感器的光源并选取单模光纤作为尾纤,基于光学设计软件Zemax纯非序列光学系统,设计了一种半导体激光器与单模光纤的耦合系统。通过分析半导体激光器的光束特性及半导体激光器与单模光纤的耦合模场理论,由一个球透镜和一个准直透镜构成组合透镜耦合方式,达到提高耦合效率和容忍度的目的。设计时在非序列光学系统下进行了百万次光线追迹,仿真得到所设计系统的耦合效率为78%左右,而实验测试结果为69.11%,由此对误差产生的原因进行了分析。     

隧道断面激光放样仪的研制

隧道断面激光放样仪基于嵌入式系统，用平移物镜法实现了在开挖断面上的激光点扫描，用单透镜准直法对发散角较大的半导体激光器实现了准直，满足了放样仪器体积小、便于携带、自动放样的要求。讨论该仪器硬件、软件实现的关键技术。     

基于532nm半导体激光器的远距离传输准直实验分析

由于半导体激光器发出的光束发散角度较大,并且是不对称的(在垂直的两个方向上发出光束的发散角度不同)。因此,在用它来做一些实际的应用时,通常需要准直或再聚焦系统来进行校正。扩束镜因其结构简单、材料便宜以及加工容易而在半导体激光束准直领域获得较多的应用。文中就是在利用半导体激光器进行远距离目标瞄准的应用背景之下,采用扩束镜与532nm半导体激光器衔接的方法对出射的激光光束进行准直,以达到一定的技术参数要求。     

10kW连续输出半导体激光熔覆光源

针对于目前国内半导体激光加工熔覆光源主要依赖于国外进口的局面,研制了连续输出功率达10kW的半导体激光熔覆光源。利用ZEMAX光学设计软件模拟半导体激光光路,包括光束整形、准直及聚焦透镜的设计等。实验中采用2只波长为915nm和2只波长为976nm的半导体激光叠阵,通过偏振合束和波长合束技术实现它的合束。由自行设计的聚焦系统进行了聚焦实验,结果显示,当模块工作电流为122A时,光源最大输出功率为10 120 W,电-光转换效率为46%,在工作面的聚焦光斑为2.5mm×18mm,可满足工业中大面积高速激光熔覆和表面热处理的要求。     

新光源半导体激光器

通过对氦氖激光器和半导体激光器的性能比较,把以往用氦氖激光器做光源的部分物理实验改用新光源半导体激光器来实验。     

Remote Continuous Wave and Pulsed Laser Raman Detection of Chemical Warfare Agents Simulants and Toxic Industrial Compounds

This study describes the design, assembly, testing and comparison of two Remote Raman Spectroscopy (RRS) systems intended for standoff detection of hazardous chemical liquids. Raman spectra of Chemical Warfare Agents Simulants (CWAS) and Toxic Industrial Compounds (TIC) were measured in the laboratory at a 6.6 m source-target distance using continuous wave (CW) laser detection. Standoff distances for pulsed measurements were 35 m for dimethyl methylphosphonate (DMMP) detection and 60, 90 and 140 m for cyclohexane detection. The prototype systems consisted of a Raman spectrometer equipped with a CCD detector (for CW measurements) and an I-CCD camera with time-gated electronics (for pulsed laser measurements), a reflecting telescope, a fiber optic assembly, a single-line CW laser source (514.5, 488.0, 351.1 and 363.8 nm) and a frequency-doubled single frequency Nd:YAG 532 nm laser (5 ns pulses at 10 Hz). The telescope was coupled to the spectrograph using an optical fiber, and filters were used to reject laser radiation and Rayleigh scattering. Two quartz convex lenses were used to collimate the light from the telescope from which the telescope-focusing eyepiece was removed, and direct it to the fiber optic assembly. To test the standoff sensing system, the Raman Telescope was used in the detection of liquid TIC: benzene, chlorobenzene, toluene, carbon tetrachloride, cyclohexane and carbon disulfide. Other compounds studied were CWAS: dimethylmethyl phosphonate, 2-chloroethyl ethyl sulfide and 2-(butylamino)-ethanethiol. Relative Raman scattering cross sections of liquid CWAS were measured using single-line sources at 532.0, 488.0, 363.8 and 351.1 nm. Samples were placed in glass and quartz vials at the standoff distances from the telescope for the Remote Raman measurements. The mass of DMMP present in water solutions was also quantified as part of the system performance tests.     

叶绿素α的激光光致发光机理及其浓度测量新方法研究

介绍了一种以红光半导体激光器作为荧光激发光源,结合光纤光谱技术测量水体中叶绿素α浓度的新方法。通过分析叶绿素α的激光光致发光机理,得出了水体中叶绿素α荧光发射光谱的相对荧光峰值强度与叶绿素α浓度的近似线性关系。实验结果表明,在红光半导体激光器激励下根据叶绿素α的荧光发射光谱直观地判断叶绿素α的浓度这种方法完全可行,由此为研制叶绿素α荧光仪提供了一种新的光源选择,并为实现现场实时监测海水中叶绿素α浓度提供了实验依据。     

Burr control in meso-punching process

The shearing process for the sheet metal is normally used in the precision elements such as semi-conductor components. In these precision elements, the burr formation brings a bad effect on the system assembly and demands the additional de-burring process, so this imposes high cost on manufacturing. In this paper, we have developed the in-situ auto-aligning precision meso-punching system to investigate the burr formation mechanism and ultimately minimize burr. Firstly, we introduced the punch-die contact sensing method to align the punch and the die at initial state prior to the punching process. Secondly, by using the low-price semi-conductor laser, burr formed on the edges is measured intermittently during the punching process. We could, finally, make burr on the sheet metal uniformized and minimized by controlling of the precision X-Y table, 1 un resolution, and measuring burr height by semiconductor laser. Experimental results show the validity of our system for pursuing the burr-free punched elements.     

半导体激光器高稳定度系统的研究与设计

半导体激光器(LD)随着温度的增加,阈值电流升高,输出功率下降.为了使半导体激光器输出激光功率稳定,设计了激光器高精度稳功率电路,使用功率MOSFET作为电流控制元件,运用负反馈原理调整输出电流,实现对激光器输出功率的控制.试验结果表明,电路设计合理,响应速度快,输出激光功率长期稳定度可以达到0.1%.     

厚膜半导体工艺在气敏元件生产中的应用

文中讲述了将厚膜半导体工艺应用于气敏元件的生产制作,综合运用精密丝网印刷、激光分割、激光调阻、平面绑定等先进技术,达到了高质量、高效率生产气敏元件的效果.应用半导体工艺制作的气敏元件相比传统工艺制作的产品具有体积小、功耗低、机械性能好、批次一致性好等优点.     

New approach to cathodoluminescence studies in application to InGaN/GaN laser diode degradation

Cathodoluminescence (CL) studies are widely applied in semi-conductor science and technology. However, for structures with a p-n junction the CL spatial distribution can be strongly affected by internal current flows of the electron beam induced current generated within the structure. This influence is the investigated in application to CL studies of degradation in aged laser diodes with InGaN multiquantum wells.     

摩托车汽缸激光表面处理工艺研究

对摩托车汽缸进行了激光表面处理工艺试验和微观分析,针对摩托车汽缸的运动特点。分析了激光处理工艺参数、光斑直径和硬化带面积、光束运动模式、硬式匹配等对激光处理的影响。道路行车试验表明,通过优化激光处理工艺,可以得到高耐磨性的汽缸,使行车寿命提高２倍以上。