用闸流管作开关的氮分子激光器

本文比较了采用闸流管和球隙作开关元件的氮分子激光特性。采用石墨作为激光器电极使激光器能在体不流动情况下以每秒50次运转。     

紫外氮分子激光器研究

本文根据氮分子激光器原理和Blumlein结构横向放电脉冲激光器的电路原理,分析各种参数如激光腔电感、电极形状、火花隙电感、传输线以及在激光器中放电开始点对激光输出的影响。研制成一种结构紧凑小型的氮激光器,此种器件最适宜作染料激光器的泵浦光源。     

铜蒸汽激光器双闸流管触发系统的研究

研制成用于钢蒸汽激光器的双间流管触发系统。用两个闸流管并联进行交替触发，总输入电功率达7．8kW。低功率运行时，激光器的效率为0．6％与单间流管激光器的效率一致。     

氮分子紫外脉冲激光器(下)

2.横向激励型氮激光器如前文所述,纵向氮激光器的优点是方向性好,结构紧凑,体积小。缺点是峰值功率不太大,其主要原因是用同轴电缆馈电,阻抗较大;放电管孔径较细;充气压力较低;放电管长度受到限制,一般不超过氮气的击穿速度与激光上能级辐射寿命之乘积。     

氮分子紫外脉冲激光器(上)

氮分子紫外脉冲激光器(以下简称氮激光器),于1963年问世,它的基本特征是:峰值功率大,一般在数兆瓦量级,最高已达60兆瓦;脉冲宽度窄,一般在10毫微秒左右,最窄已达0.6毫微秒;重复工作频率高,一般可达每秒几十次到一百次,最高已达1300次/秒;输出激光处在紫外波段,波长为3371埃;结构简单,制造容易,造价较低。氮激光器应用很广,它所发出的3371埃紫外光广泛应用于泵浦染料激光器及激光光谱、污染探测、集成光学、农业育种、癌症诊断、石油勘探等方面。     

真空紫外氢激光器

真空紫外激光器可为化学工作者提供足够的光子能量,以打破许多化学键,其短脉冲则适于进行动力学研究。     

脉冲紫外氮激光器

进行了具有体放电的脉冲氮激光的研究。获得输出峰值功率达2兆瓦和平均功率150毫瓦。讨论建立具有峰值功率50~100兆瓦和平均值达5瓦的紫外氮滤波器的可能性。     

氮分子激光器

随着我国激光新技术在工农业生产中日益广泛的应用,对激光器件的研制提出了更高的要求,产品的数量远远不能满足日益增长的需要,品种更落后于生产的发展,特别在全国人民大办农业的大好形势下,广大科技人员与贫下中农相结合开展科学种田,激光育种已初见成效,同时要求更多品种、不同能量、不同波长的激光器件,为育种提供更多实验条件.     

Optical self-routing switch using integrated laser diode opticalswitch

A 2×2 optical self-routing switch using integrated laser diode optical switches is proposed. The switch is composed of a Benes network, which can perform large-scale switching functions using less hardware than a crossbar switch. The path each data stream takes through the interconnection network is determined by the binary bits of its destination address, and self-routing is accomplished by monitoring terminal voltage changes in gain guides induced by input optical signals which are injected into a p-n junction. Concentrated control is not necessary, and large optical multistage switches can be easily constructed because complicated electrode patterns are not necessary     

All-optical active switch using a multiple quantum well nonlinearetalon as a laser diode mirror

A GaAs/AlGaAs multiple quantum well nonlinear etalon with a Bragg reflector was used as a feedback mirror of an external cavity laser diode. The laser oscillation was switched on/off by an external control light with high contrast ratio of 30:1     

The MAPS-40 burst-mode 40-kV megawatt average power hydrogen thyratron

A hydrogen thyratron capable of switching 40 kV and 40 kA in repetitive bursts at the 1-MW average power level is described. Major design problems were obtaining the necessary forward and inverse holdoff capability and controlling the thermal and mechanical effects of the several kilowatts of operating dissipation encountered at this power level. A conventional external anode, planar-electrode, ceramic-metal tube design was chosen to meet the design requirements, which include reliable, kickout-free operation following long periods of standby. Emission was provided by a large cathode specifically designed to handle ohmic heating due to the 1500 A of rms-equivalent pulse current, as well as the heat developed in the surrounding plasma. Massive auxiliary, control, and gradient grids were incorporated into a tightly baffled box-type grid structure of sufficient total aperture area to prevent quenching below 70-80 kA. Molybdenum wall shielding was employed to improve holdoff capability and prevent arc damage. Design and operating considerations are discussed and representative test results for the first 16 tubes are given, together with the results of special tests for high peak current, high average current, and high-voltage holdoff.     

紫外光激光加工盲孔的工艺研究

紫外光(UV)激光因波长短、能量大、加工精度高等优点,被越来越多地应用到PCB微孔制作工艺中。文章研究了UV激光加工φ200μm的盲孔,通过正交试验分析了激光功率、加工速度、激光频率和Z轴高度等各因素与钻孔深度之间的关系,且获得了UV激光制作一阶与二阶盲孔的最佳工艺参数和方法。研究结果表明,钻孔深度随着激光功率和加工速度的增大而增大,而激光频率的增加使钻孔深度减小。     

UV pre-ionized wide-aperture XeCl laser using magnetic pulsecompression

To provide a spatially homogeneous and sufficiently high-voltage discharge, the laser described here used LC inversion and two-stage magnetic pulse compression in the excitation circuit and used UV radiation for pre-ionization. It also employed one commercial thyratron as a high-voltage switch. Evaluation of the dynamic magnetic characteristics of four magnetic materials in a magnetic pulse compression circuit showed that the Fe-based nanocrystalline soft magnetic alloy was the best core material for a compact switch with low core loss. At a 10 Hz repetition rate the maximum output energy obtained in a 80×60 nm discharge cross section and in 70 ns pulses (FWHM) was 6.2 J     

Fabrication of semiconductor optical switch module using laser welding technique

The 4/spl times/4, 1/spl times/2, and 1/spl times/4 semiconductor optic-switch modules for 1550 nm optical communication systems were fabricated by using the laser welding technique based on the 30-pin butterfly package. For better coupling efficiency between a switch chip and an optical fiber, tapered fibers of 10-15 /spl mu/m lens radius were used to provide the coupling efficiency up to 60%. The lens to lens distance of the assembled tapered fiber array was controlled within /spl plusmn/1.0 /spl mu/m. A laser hammering technique was introduced to adjust the radial shift, which was critical to obtain comparable optical coupling efficiencies from all the channels at the same time. The fabricated optical switch modules showed good thermal stability, with less than 5% degradation after a 200 thermal cycling. The transmission characteristics of the 4/spl times/4 switch module showed good sensitivities, providing error free transmissions below -30 dBm for all the switching paths. The dynamic ranges for the 4/spl times/4 and 1/spl times/2 switch modules were about 8 dB for a 3 dB penalty and about 17 dB for a 2 dB penalty, respectively.     

一种可防止闸流管连通的卤化铜激光开关电源

本文给出的一种开关电源电路,由于采用了特定的供电电压,以保证在闸流管消电离之前充电回路中没有电流,从而可望解决闸流管的连通问题。实验结果与理论预期的一致。     

紫外激光切割Si片的实验研究

报道了用193nm准分子激光切割硅片的实验结果。采用柱透镜光学系统及“热劈裂法”获得小于15μm的切缝及小于5μm的切面不平整度。     

使用无Q开关脉冲激光器拍摄全息肖像的研究

通常认为拍摄脉冲全息肖像必须使用带有Ｑ开关运转模式的脉冲激光器，否则是不可能拍摄成功的。本文介绍了我们使用无Ｑ开关的脉冲激光器研制出高质量脉冲质量肖像的工作，以及在此情况下应注意的若干问题。