激光光子复合治疗面部毛细血管扩张症疗效观察

目的:探讨强脉冲光结合激光治疗面部毛细血管扩张的疗效.方法:自2008年9月至2009年9月,采用540nm强脉冲光及1064nm LP Nd:YAG激光对50例面部毛细血管扩张患者进行治疗.根据患者面部的皮肤类型及毛细血管扩张程度,选择适当的治疗参数,其中540nm强脉冲光能量密度13～16J/cm~2;1064nm LP Nd:YAG激光能量60～100mJ,治疗1～6次,平均1.84次,每次治疗间隔1个月.结果:治疗后随访3～6个月,治愈率68.00%,总有效率100%.无不良反应发生.结论:采用540nm强脉冲光结合1064nm LP Nd:YAG激光复合治疗面部毛细血管扩张症其疗效确切,效果满意.     

多脉冲激光辐照皮肤组织的光热效应实验研究

通过实验测定了离体乳猪皮肤组织在多脉冲Nd:YAG激光辐照下径向和轴向不同位置的温度分布,重点研究了激光辐照能量密度、脉冲重复频率以及波长对皮肤组织温升分布的影响.研究结果表明:皮肤组织中的温度分布与探测位置、激光辐照能量密度、脉冲激光的重复频率以及波长密切相关;在激光辐照时间为40 s的情况下,同一波长同一频率时组织温度随能量密度的增加而增大,波长1064 nm、霞复频率10 Hz时的安全光剂量阈值为1118.19 mJ/cm2;同一波长同一能量密度时,组织温度随脉冲激光重复频率的增加面增大;同一能量密度同一频率时,波长为1 064 nm的多脉冲激光辐照皮肤组织时的光热效应较532 nm波长明显.     

强脉冲光治疗面部面部毛细血管扩张症46例

目的:观察540 nm强脉冲光治疗面部毛细血管扩张症的临床效果。方法:对46例面部毛细血管扩张症患者采用540 nm强脉冲光治疗,根据不同临床情况选择不同能量。结果:1、2、3、4、5次的治愈率分别是25.00%、38.46%、55.00%、71.43%、100.00%,有效率分别是50.00%、84.62%、90.00%、85.71%、100%。治疗次数越多,有效率越高。结论:540 nm强脉冲光治疗面部毛细血管扩张症安全有效。     

585nm脉冲染料/1064nm Nd：YAG复合激光治疗痤疮的疗效观察

目的：观察585nm脉冲染料/1064nmNd：YAG复合激光治疗痤疮的疗效及安全性。方法：应用585nm脉冲染料/1064nm Nd：YAG复合激光对丘疹脓疱性痤疮患者35例以及红斑性痤疮患者26例进行治疗。每4周治疗1次,一共治疗3次。脉冲染料的能量为6.5J/cm2至9J/cm2、1064nmNd：YAG激光为30J/cm2至60J/cm2前者脉宽为0.5ms,后者为15ms：光斑大小均为7mm。丘疹脓疱性痤疮对照组35例外用0.025%维甲酸霜,每晚1次;1%克林霉素磷酸酯凝胶涂抹患处,每天早晨1次;同时口服盐酸米诺环素胶囊0.1g Q12H。结果：治疗的第4周、8周、12周,丘疹脓疱性痤疮患者激光组的平均疗效指数分别为49.83%、75.49%、80.83%,平均Leeds评分分别为0.88、0.69、0.29;红斑性痤疮患者平均疗效指数分别为32.66%、62.14%、83.31%。12周后,丘疹脓疱性痤疮和红斑性痤疮患者激光组的有效率分别为97.14%、88.57%。绝大多数激光治疗者皮肤弹性得到不同程度改善,皮脂分泌有所减少。所有激光治疗者均出现轻微的红斑,但均在24小时内消退;31例患者出现紫癜,一般1-2周内消退不留痕迹;2例患者出现暂时性水疱,未见其他副反应。结论：585nm脉冲染料/1064nmNd：YAG复合激光治疗丘疹脓疱性痤疮及红斑性痤疮有效且副作用小。     

铒/镱共掺光纤的超荧光研究

研究了铒/镱共掺光纤的超荧光特性,用4.5 m长铒/镱共掺光纤在248 mW的1 064 nm Nd∶YAG激光泵浦下,在峰值波长1 534.96 nm处,光谱3 dB带宽为1.76 nm.其输出光功率达23 mW,斜率效率为12.9%,输出功率稳定性为±0.05 dB.     

Q开关Nd:YAG激光治疗150例文身临床分析

目的:观察Q开关Nd:YAG激光对文身的治疗效果。方法:用Q开关Nd:YAG激光治疗不同类型的文身,能量密度5～12J/cm2,脉冲宽度5～7ns,重复频率1、2、5、10Hz,光斑尺寸2、3、4、6mm可调,对于文身较深者需多次治疗,每次间隔三个月。结果:共治疗150例,一次治愈率30％,总有效率达100％。结论:Q开关Nd:YAG激光治疗文身,组织损伤小,痛苦少,不留疤痕。     

Nd3+:KGd(WO4)2激光晶体的性能研究

采用熔盐提拉法生长出φ20 mm×60 mm的优质Nd3+:KGd(WO4)2晶体,对晶体三个轴向的光谱进行测试研究表明a轴向的吸收和荧光谱峰最强,最适合于进行激光实验研究.用600 m波长的染料短脉冲(束腰为420μm)激光纵向抽运φ3.5 mm×30mm晶体激光器件,对1352.5 nm激光进行腔内拉曼散射频率自转换,在1539.5 m人眼安全波段实现了44μJ/pulse的激光输出,光-光转换效率为1.26%.用脉冲氙灯抽运φ3.5 mm×26 mm的激光器件,在1.067 μm处得到125.5 mJ的激光输出,激光阈值为≤1.6 mJ.在同等条件下对φ3.5 mm×35 mm的YAG:Nd激光晶体进行了激光实验研究和YAG:Nd3+晶体相比,KGW:Nd3+晶体具有激光阈值低、效率高和输出光为偏振光等优点,因此在小型激光器的应用方面具有明显的优势.     

长脉冲激光与金属相互作用影响分析

通过使用1 064 nm,Nd：YAG长脉冲激光作用在金属材料从理论和数值模拟的角度研究各种因素对激光加热效应的影响。针对国内外目前长脉冲激光与物质相互作用研究的现状,分析和模拟了长脉冲激光与材料相互作用过程中的各种现象和问题,特别是对长脉冲激光与金属相互作用时的温度场及应力场进行了较全面的理论分析。就靶材物质对激光的...     

1339nm单一谱线Nd:YAP脉冲激光器

介绍了一台a轴偏振的1 339 nm Nd:YAP脉冲激光器.通过分析Nd:YAP晶体的能级跃迁和光谱特性,采用偏振片抑制平行于晶体C轴偏振的激光振荡,并通过设计输出耦合镜的透过率抑制晶体a轴偏振的1 064 nm强线的振荡,成功实现a偏振的1 339 nm单一谱线脉冲激光输出.当输入电能量达到75 J时,激光输出能量为0.31 J,电-光转换效率为0.4%,斜率效率为0.52%,激光输出能量不稳定度≤±5%,激光阈值能量为14.5 J,输出脉冲激光的中心波长在1 339.2 nm.     

超短脉冲激光频率的线性及非线性扩展

通过采用若干激光增益介质和非线性频率变换技术,有效地扩展了皮秒及飞秒激光的波长.在可见光波段,利用自建的高能量400 nm倍频皮秒钛宝石激光作泵浦,通过LBO参量放大,得到了波长从450～750 nm可调、最高单脉冲能量达30 mJ的可调谐皮秒激光脉冲;在红外波段,通过上述方案不仅产生了波长850 nm～3.6μm的皮秒闲频光,而且相继利用Cr:Mg2SiO4和Cr:YAG晶体作为增益介质,获得了中心波长分别在1 280 nm和1 450 mn波段的飞秒激光脉冲.利用Yb:YAG、Yb:GYSO、Nd:GdVO4、Nd:LuVO4等晶体作增益介质,获得了中心波长1 053、1 093 nm的飞秒激光脉冲及912、916 nm的皮秒脉冲.这些具有不同波长特性的超短脉冲激光光源,可望在许多领域获得重要应用.     

Pulsed antennas

The problem of pulsed antennas has two complementary parts: i) analysis of the radiation field when the driving voltage is given and ii) synthesis of the driven voltage when the radiation field is given. In this paper a number of heuristic procedures are presented, relating to the computation of transient radiation from elementary sources, coaxial apertures, infinitely long cylindrical antennas, finite cylindrical antennas, and loop antennas. Comparison with available rigorous solutions and experiments is also provided.     

Pulsed wave interconnect

Pulsed wave interconnect is proposed for global interconnect applications. Signals are represented by localized wave-packets that propagate along the interconnect lines at the local speed of light to trigger the receivers. Energy consumption is reduced through charging up only part of the interconnect lines and using the voltage doubling property of the receiver gate capacitances. In a 0.18-/spl mu/m CMOS technology case study, SPICE simulations show that pulsed wave interconnect can save up to 50% of energy and /spl sim/30% of chip area in comparison with the repeater insertion method. A proposed signal splitting structure provides reasonable isolations between different receivers. Measured S-parameters of 3.8-mm interconnect lines fabricated through CMOS foundry showed that the distortion and attenuation of a pico second signal are much less serious than the theoretical predictions. Pulsed wave interconnect also enables time division application of a single line to boost its bit rate capacity. The use of nonlinear transmission lines (NLTL) is also proposed to overcome pulse broadening and attenuation caused by dispersion and frequency-dependent losses. Pulsed waves on an NLTL may be generated, transmitted, split and detected with components realizable in bulk and SOI CMOS technologies. Tapered NLTL can be used for pulse compression. NLTL edge sharpening abilities may be applicable for signal rise time control.     

Pulsed metallic-plasma generators

A pulsed metallic-plasma generator is described which utilizes a vacuum arc as the plasma source. The arc is initiated on the surface of a consumable cathode which can be any electrically conductive material. Ignition is accomplished by using a current pulse to vaporize a portion of a conductive film on the surface of an insulator separating the cathode from the ignition electrode. The film is regenerated during the ensuing arc. Over 10⁸ignition cycles have been accomplished by using four 0.125-in (0.318-cm) diameter zinc cathodes operating in parallel and high-density aluminum-oxide insulators. A plasma consisting of cathode material is emitted at the rate of about 10^-7kg for each coulomb of charge emitted. The plasma is ejected in the form of a high-velocity highly directional conical plume through a ring-shaped anode. One or more magnetic field coils may be used to control the impedance and the direction of the plume. The normal pulsed operating parameters for the generator are a few hundred volts and a few hundred amperes with pulsewidths ranging from 50 to 500 µs and repetition frequencies up to 300 pulses per second (pps). Among the applications being investigated for the generator are metal deposition, vacuum pumping, electric propulsion, and high-power dc arc interruption.     

脉冲激光沉积工艺

脉冲激光沉积是一种新型沉积工艺，跟其它沉积工艺相比它具有许多的优点，这是因为在沉积过程中其靶材料的相对原子浓度可保持不变，从而可制备出理想配比的沉积薄膜。本文介绍了采用这种脉冲激光沉积工艺制备而成的新型ＺｎＯ：Ｇａ透明导电薄膜，以及Ｚｎ－Ｇａ２Ｏ４和Ｙ３Ａｌ５Ｏ１２：Ｔｂ荧光薄膜。     

Metaparticles of Pulsed Wave Fields

Properties of elementary particles of pulsed (localized) electromagnetic and acoustic wave fields directionally radiated by aperture sources (antennas, lasers, acoustic diaphragms) in free space and homogeneous isotropic media, for which the term metaparticle is used, are considered. The structure of the wave field and the energy transferred by the metaparticles are presented. The results obtained for the presented scalar theory of metaparticles of pulsed transverse electromagnetic (TEM) waves and longitudinal elastic acoustic waves can be extended to vector pulsed wave modes guided by layered inhomogeneous guiding media and guiding technical devices (waveguides).     

脉冲双包层光纤激光器

双包层光纤激光器具有光束质量好、散热面积大等优点。介绍了三种获得脉冲输出的双包层光纤激光器，即调Q光纤激光器、锁模光纤激光器及振荡放大脉冲光纤激光器。分析了它们的工作原理及关键技术，并对国内外近期进展作了综述。     

Millimeter-Wave Pulsed IMPATT Sources

High-power millimeter-wave pulsed MPATT sources have found a variety of applications as solid-state transmitters in RADAR applications. These applications have been greatly enhanced by the rapidly advancing millimeter-wave technology of which the high-power pulsed IMPATT source is a key element. In this paper the unique IMPATT properties which affect the oscillator spectral purity and coherency are reviewed. Some key considerations for the device design and system applications of the pulsed oscillators are discussed along with the state of the art, recent progress, and future trend.     

脉冲激光波长计

本文回顾了脉冲激光波长计的发展过程。介绍了有代表性的二种脉冲激光波长计。简要介绍了我们研制脉冲激光波长计的工作。     

Pulsed hydrogen fluoride lasers

The spectral distribution of the output of a pulsed HF laser shows evidence of cascading from theupsilon = 2level to the ground state. Both calculations and experimental results indicate gain coefficients of 1 cm^-1at HF pressure of 1 torr.     

卟啉在脉冲激光作用下的化学反应

以倍频Nd:YAG激光器的脉冲ns辐射,对几种卟啉在三种溶剂(氯仿、苯、甲醇)中的作用进行了研究.对于PPM、HPM和TPP三种卟啉,只有当在CHCl_3溶剂中辐照时才有新的光谱出现和原始光谱消失的情况发生,在苯和甲醇中并非如此.所形成的反应产物经鉴定为相应的质子化卟啉.我们认为氯仿的介电击穿是卟啉质子化的起因.