共查询到20条相似文献,搜索用时 125 毫秒
1.
2.
半导体激光器的一种新调制方法 总被引:1,自引:1,他引:0
半导体激光器的一种新调制方法强锡富,孙晓明,朱茂华,王晓慧(哈尔滨工业大学)0引言半导体激光器(laserDiode,下简称LD)由于具有体积小、易调制、结构简单、输入能量低等许多优点而得到广泛应用[1]。尤其是LD的调制特性,其输出光频的调制不用机... 相似文献
3.
半导体激光器列阵的smile效应与封装技术 总被引:4,自引:0,他引:4
为了减小半导体激光器列阵在封装过程中引入热应力而产生的smile效应,提高半导体激光器列阵光束质量,利用对半导体激光器列阵发光点成像放大的方法,准确测量了半导体激光器列阵的smile效应,测量误差为±0.1μm。由于smile效应的准确测量能客观地比较减小smile效应的各种技术与方法,本文根据分析测量结果,提出了通过优化封装半导体激光器列阵焊接回流曲线的方法,使smile效应值控制在±0.5μm内。该方法减小了半导体激光器列阵的smile效应值,提高了激光器列阵光束质量,为下一步研制小芯径、高光束质量半导体激光器列阵光纤耦合模块提供了基础条件。 相似文献
4.
5.
6.
半导体激光干涉仪在信号倍频处理中的应用 总被引:1,自引:3,他引:1
半导体异质结激光器在注入的电流发生变化时 ,输出激光的光频也随之改变。适当地设计干涉仪的参数 ,可检测这种变化。提出了可将干涉仪设计为信号倍频器及调制器 ,通过实验给出了分析方法与结论 相似文献
7.
半导体激光器直接电控稳频方法 总被引:1,自引:0,他引:1
提出了运用数字控制方法直接控制半导体激光器的结压降来实现稳定半导体激光器输出光频的新方法,推导了原理公式,并给出了实验方案和结果,分析了影响实验结果的因素。 相似文献
8.
9.
10.
针对在半导体激光器自混合干涉( SMI )微位移测量中,测量噪声对 SMI 信号条纹计数极易引入误差,提出一种基于 Savitzky Golay ( S-G )滤波与包络提取的 SMI 信号处理算法,对自混合信号处理并识别条纹后,干涉条纹能够得到准确地计数。该算法采用 S-G 卷积均值滤波处理、三次样条函数插值包络分析和信号归一化处理,可以有效消除噪声高频信号和提取信号包络。采用电压调制模式下驱动压电陶瓷( PZT )产生微振动作为模拟振动源,实验中设置 3 组不同电压调制幅值下的振动源,采集并分析 SMI 信号及相应振幅信息。在 3 组实验当中,经过算法处理过的 SMI 信号,其干涉条纹数与电压调制 PZT 振动幅值由处理前偏离线性关系到处理后保持线性关系。实验结果表明,经 S-G 滤波与包络提取算法处理过的 SMI 信号能真实反映微米量级的微位移。 相似文献
11.
GUO Dongmei WANG Ming School of Physical Science Technology Nanjing Normal University Nanjing China 《机械工程学报(英文版)》2007,20(3):83-85
ASeblsf-tmraicxti:n gA innteewrf esreelnf-cme ioxcincgu rms iicnr oa -liansteerrf derioodmee t(eLrD b)a sbeyd r eofnl eecxtitnergn tahl ep lhiagshet fmroomdu ala tmioinrr oisr-plirkees etanrtgedet. in front of the laser. Sinusoidal phase modulation of the beam is obtained by an electro-optic crystal (EOC) in the external cavity. The phase of the interference signal is demodulated by Fourier analysis method. The combination of the modulation and demodulation decreases the sensitivity of the instru-ment to fluctuations of the laser power and the noise induced by environment. Experimentally, the new micro-interferometer is applied to measure the micro-displacement of a high precision commer-cial PZT with an accuracy of <10 nm. 相似文献
12.
A dispersion interferometer is one of the promising methods of the electron density measurement on large and high density fusion devices. This paper describes development of a CO(2) laser dispersion interferometer with a photoelastic modulator for phase modulation. In order to make the dispersion interferometer free from variations of the detected intensity, a new phase extraction method is introduced: The phase shift is evaluated from a ratio of amplitudes of the fundamental and the second harmonics of the phase modulation frequency in the detected interference signal. The proof-of-principle experiments demonstrate the feasibility of this method. 相似文献
13.
A compact and inexpensive iodine-stabilized diode laser system with an output at 531 nm has been applied to long gauge block measurements. Although the optical frequency of the output beam was widely modulated (modulation width of ∼22 MHz), the coherence length and interference phase stability are sufficiently long and high, respectively, for the interferometric measurement of long gauge blocks of up to 1000 mm in length. The effective uncertainty of laser frequency in the interferometric measurement was theoretically and experimentally confirmed to be less than 10−9. 相似文献
14.
为了满足工程中一些特殊二维位移测量需求或提高位移测量效率,建立了结构简单紧凑的激光自混合干涉双通道位移测量系统。首先,基于三镜法-珀腔模型给出自混合干涉系统的数学方程。其次,在弱反馈条件下施加线性电流调制,依据自混合信号频率和外部物体距离的线性关系,当两个物体到激光器距离不同时,频域会呈现两个独立的谱峰,分别对其进行相位解算,从而实现自混合双通道位移测量。然后,数值模拟生成了双通道激光自混合信号,根据全相位频谱分析技术对自混合信号两个谱峰的相位进行估算,重构了两个物体位移曲线,给出了仿真验证。最后,搭建了实验系统,进行了自混合干涉双通道位移测量实验,并给出实验测量结果。实验结果表明,该系统可以完全区分两个运动物体,位移测量相对误差优于8.42%。线性调频激光自混合干涉可以实现任意运动规律的双通道位移测量,通过继续分光其测量通道数仍可进一步增加。 相似文献
15.
Fringe counting method with laser diodes (LDs) for displacement measurement has been constructed. Two LDs are frequency modulated by mutually inverted sawtooth currents on an unbalanced two-beam interferometer. The mutually inverted sawtooth-current modulation of LDs produces interference fringe signals with opposite signs for respective wavelengths. The two fringe signals are fed to an electronic mixer to produce a synthetic fringe signal with a reduced sensitivity to the synthetic wavelength. Synthetic fringe pulses derived from the synthetic fringe signal make a fringe counting system possible for faster movement of the tested mirror. 相似文献
16.
V. F. Zakhar’yash A. V. Kashirskii V. M. Klement’ev 《Optoelectronics, Instrumentation and Data Processing》2015,51(6):553-559
This paper presents the results of experimental studies of active mode-locking in an external-cavity semiconductor laser. Two methods of obtaining active mode-locking regimes have been studied: by modulation from an external generator with a frequency close to the intermode frequency of the external laser cavity and by laser current modulation at the frequency of intermode beats of the external laser cavity through an amplification feedback loop. In the first case, a stability of intermode beats of 10-14 is experimentally achieved, and in the second case, it is shown that semiconductor laser current modulation by an amplified intermode beat signal from the output of a photodetector provides a stable mode-locking regime also with mode frequency tuning, i.e., a mode-locking regime involving intermode frequency tuning with optical cavity tuning. The effects that accompany mode locking, in particular, the pulling effect and the stability of the mode-locking regime, and possibility of obtaining highly stable intermode beats by suppressing the amplitude noise component in the modulating signal have been studied. A phenomenological study of the pulling and phase locking of the intermode frequency is attempted. 相似文献
17.
18.
19.
20.
可调谐激光光谱(TDLAS)技术利用激光管的波长扫描实现痕量气体吸收曲线的二次谐波检测,具有响应时间短、检测灵敏度高、精度高等优点。但实际应用条件分析结果表明,烟道气在线检测中存在外界环境和系统本身引入的噪声。为了实现TDLAS检测方法的高精度、高灵敏度等优势,本文提出在检测系统中加入温度反馈,以减少高温环境带来的干扰,设计并采用双光路扣除背景,消除颗粒物及背景吸收干扰以及采用对激光管驱动电流进行高频调制来抑制系统噪声等3条主要的降噪途径。理论分析表明,这些措施可以降低环境干扰及系统噪声影响,有效提高检测精度。 相似文献