多模光镊的实验研究

简述了激光光镊的原理，研究了单模、多模光镊的特点，给出了一个用多模激光作为光源的光镊的设计思想和实际装置，并用此光镊对生物细胞进行了捕获实验。该装置价廉、衫，很容易在一般实验室实现。     

激光光镊技术在单细胞、单分子科学中的应用研究

首先阐明了单细胞、单分子分析与研究的学科价值和社会意义：强调了激光光镊技术的出现对促进单分子、单细胞科学的发展的实际贡献;介绍了光镊的物理原理和工作特点;着重总结了激光光镊技术在单分子、单细胞领域的具体应用情况,并结合详细的研究工作,对这一技术的开发完善和应用发展给出了一些评述和建议：阐述了光镊技术在单细胞、单分子研究中的潜在地位和巨大的发展前景。     

利用飞秒激光光镊捕获生物细胞

采用自行搭建的飞秒激光光镊,实现了对人体血红细胞（RBC）的稳定捕获。使用的光源为自行搭建的掺钛蓝宝石克尔透镜锁模激光器,输出中心波长810nm、脉冲宽度40fs和重复频率为100MHz的飞秒激光脉冲。通过实验比较了飞秒激光光镊和连续（CW）激光光镊的捕获能力,依据实验数据,比较了两者的Q值。实验结果显示,飞秒激光光镊对于捕获生物细胞同样有效,将光镊技术和飞秒激光特性相结合用于生物学研究领域会有很好的应用前景。     

激光光镊对生物体的光操纵研究

根据光镊捕获电介微粒的理论研究结果 ,简析了光对生物体的力学作用 ,给出了用不同参量的激光陷阱操纵不同种类的微生物的实验结果 .分析比较表明 ,生物体的预培养是实现光操纵的重要环节 .     

光镊技术的研究现况

光镊技术是激光技术的重大发明,能利用光的动量与物质相互作用产生光势阱效应,已成为微纳米微粒操控和皮牛顿力测量的重要工具。光镊技术不仅丰富和推进了光学领域的发展,也为光学与多学科的交叉融合架起了一座桥梁,彰显出了它独特而不可替代的作用。综述回顾了30年来光镊理论和技术的发展,系统梳理了光镊在细胞生物学、单分子生物学、软物质胶体科学以及物理纳米科学等领域的应用,并列举典型的应用实例,探讨了光镊技术应用的特点,展望了光镊技术应用蓬勃发展的美好未来。     

激光微束细胞操作系统

提出构建一种用于生物细胞操作的激光微束系统.即由Nd:YAG激光经物镜聚焦形成的光刀和He-Ne激光器经物镜聚焦形成的光镊组成的激光微束系统,进行了总体设计、关键部件设计和选择.在构建的激光微束操作实验系统上实现了非接触细胞操作,验证了光镊的力学效应.采用Nd:YAG经显微物镜会聚形成光刀可以对细胞或细胞器进行打孔或切割染色体.     

一种用于生物研究的光镊与激光微束系统

分析光镊与激光微束的性质和特点,研究两者相互配合、联合操作的技术及优势。在国内首次实现光镊与微束激光的耦合技术,这种全新的显微操作系统可对活体细胞进行全方位操作与微加工。     

光镊技术在生命科学研究中的应用

激光光镊自从1986年发明以来,作为一种无直接接触、无损伤、可产牛和检测微小力以及精确测量微小位移的物理学工具,在生命科学领域得到了广泛的应用.阐释了光镊的基本原理及其在生命科学研究应用中所涉及的关键技术细节,总结了近年来光镊技术的新进展.     

飞秒激光光镊轴向力的计算与分析

光镊已成为捕获和操纵微米尺度粒子和生物细胞的有效手段，而目前常用的光镊光源为连续激光或长脉宽的脉冲光。提出飞秒激光光镊的概念．将飞秒激光序列脉冲视为对连续光的周期抽样，借助于连续光光镊的分析方法，建立了飞秒激光光镊对电介质微粒产生的轴向光学力的理论模型。给出影响捕获微粒的主要因素，指出存在最佳束腰半径和被捕获粒子半径。数值计算结果表明选取合适的飞秒激光脉冲能量、束腰半径、脉冲波长以及微粒与周围媒质的相对折射率．微米尺寸的微粒完全能被飞秒激光稳定捕获。综合考虑被捕获微粒所受的脉冲式光学梯度力、重力和布朗惯性力的作用，讨论了飞秒激光光镊轴向光学梯度力的脉冲式特点及实现稳定捕获的条件。     

单模光纤微探头式光镊技术

通过对平端面和基于半球形自透镜端面的单模光纤微型探头光镊技术的研究．表明单模光纤微型探头式光镊系统结构简单、捕陷范围大、操纵灵活,可以适应更多的生物细胞和生物分子的光微操作需求．扩大了激光微操纵技术在生命科学中的应用范围。     

同时测量光电导响应和少子寿命分布的两个半导体激光器的组合使用

介绍使用两个红外半导体激光器，一束为可调谐Ｐｂ１－ｘＳｎｘＴｅ激光．另一束为ＧａＡｓ／ＧａＡｌＡｓ激光，经光学系统均会聚成φ２５０μｍ的小光点，且将二光斑成象在同一位置上．实验测量了光斑的尺寸，最后用此光学系统研究了窄禁带半导体Ｈｇ１－ｘＣｄｘＴｅ的稳态光电导响应和少子寿命分布．     

激光二极管的光功率数字可调控制系统设计与仿真

小型测量仪及通讯仪器通常采用激光二极管作为其光源,这是因为它具有体积小、效率高、结构简单和价格便宜等优点.但是激光二极管的运行质量,与其驱动电源的性能密切相关,电流的起伏会引起光功率的变化,这就需要高性能电源驱动系统才能获得稳定、准确可调的光功率输出.根据激光二极管的工作原理,设计了以单片机控制为核心采用模糊控制技术以及附加一路参考信号的激光二极管光功率数字可调控制系统.系统利用智能模糊控制技术,可有效实现激光二极管光功率的实时控制和显示,可以获得稳定、准确可调的光功率输出.     

Reliability estimate for semiconductor laser module ILPN-134

The reliability of the ILPN-134 is investigated laser module. The technique, which allows one to estimate what contribution is introduced by individual processes of aging of the laser diode and the optical system to the degradation of the laser module ILPN-134, is suggested. The activation energies of degradation processes, the standard deviations, and the failure rates of the laser diode and the optical system are determined.     

Photonic - Tiny Infrared Wavelength Laser Diode with 150 mW Optical Output

The modular design enables the TDL90 to operate across a large range of wavelengths -200 nm to 4,5 μm-with several linewidth and tracking options. Its quality and reliability have set the standard for tunable dye lasers for many years. The TDL90 dye laser has a modular design that makes it flexible and easy to adapt to researchers＇ future needs.     

光纤甲烷气体传感器的研究

基于甲烷气体近红外吸收的机理,研究了一种高灵敏度易于实现的光纤甲烷气体传感器。分析了半导体激光器的调制特性和谐波检测的基本原理,建立了传感器的数学模型。系统采用分布反馈式半导体激光器做光源,气室采用小型渐变折射率透镜构成的气室,加入参考光路和参考气室,使光源输出的中心波长锁定在气体的吸收峰上,通过光源调制实现气体浓度的谐波检测,给出了甲烷气体测量的实验结果。     

A new approach to an optical attenuator for a time compressionmultiplex system using a laser diode as both transmitter and receiver

A novel method of constructing an optical attenuator for a time compression multiplex system with a laser transceiver is proposed and investigated. The main purpose is to achieve wide dynamic range in a receiver. The transceiver consists of a laser diode backed by a photodiode. At average power levels, the laser diode is the main photodetector. At higher than average levels, the laser diode acts as an optical attenuator for the photodiode. The laser diode is called the laser attenuator (LATT). Basic properties of the proposed LATT, such as wavelength and polarization dependence, are clarified. The LATT is confirmed to have an optical dynamic range of over 37 dB     

A Consideration of an Optical Coupler for Optical Submarine Transmission Laser Redundancy Systems

Theoretical and experimental results are described for a new optical coupler which consists of two laser diodes, two GRIN spherical rod lenses, a polarizing filter, and a single-mode fiber, and which employs laser diode polarization characteristics for an optical submarine transmission laser redundancy system. This optical coupler has two channels at 1.3 μm wavelength. Optical coupler loss values, which include coupling loss, polarization loss, and assembly loss, are 4.9 dB for one laser diode and 5.2 dB for another laser diode. Such loss values are almost the same as the conventional laser diode module loss for a single-mode fiber. This paper describes in detail a laser redundancy system in an optical submarine transmission system, structure and characteristics of an optical coupler, and experimental results on a high bit rate long-haul transmission system using the proposed optical coupler.     

Effect of laser-diode power change on optical heterodyneinterferometry

A dynamic interferometer with a frequency-ramped laser diode (LD) has been constructed that is based on an optical heterodyne technique. Effect of LD power change on the optical heterodyne interferometry has been investigated theoretically and experimentally. A general formulation of the interferometry has been presented in which the demodulation scheme is analyzed in the frequency domain by Fourier-transforming a beat signal. Phase errors caused by the LD-power variation alter sinusoidally with the same period as the interference beat signal. The error can be eliminated by using an amplitude-stabilized, frequency-modulated laser diode source in the interferometer. The stabilization of the LD amplitude can be achieved by a feedback system with a superluminescent diode as an external light-power controller     

LD Redundancy System Using Polarization Components for a Submarine Optical Transmission System

An LD redundancy system having one cold standby laser diode is proposed to improve reliability in submarine optical transmission systems. This system makes use of the intrinsic laser polarization and consists of two LD modules and a polarization coupler connected by polarization maintaining (PANDA) fibers. The optical power insertion loss of this LD redundant system is 5.5 dB, including coupling loss between the laser diode and PANDA fiber. This LD redundant system will be applied in submarine optical repeaters.     

Performance of Random Metal-Dielectric Film on Optical Signal Transmissions

The transmission performances of a random metal-dielectric film composed of silver metal and spherical fused silica balls were experimentally investigated for intensity- and frequency-modulated optical signals. The film was formed on the facet of a laser diode, and intensity-modulated optical signals emitted from the laser diode were successfully transmitted through it. Frequency-modulation optical signals were successfully detected by using an optical heterodyne technique. These results indicate that this random metal-dielectric film is well suited for use as a waveguide for optical signal transmission.