Erbium-doped CW and Q-switched fiber ring laser with fiber grating Michelson interferometer

The band-pass characteristic of fiber grating Michelson interferometer is analyzed, which acts as bothband-pass filter and Q-switch. An erbium-doped fiber ring laser based on fiber grating Michelsoninterferometer is implemented for producing single longitudinal mode CW operation with 5 MHz spectrallinewidth and up to 6 mW output power. In Q-switched operation, stable fiber laser output pulses withrepetition rate of 800 Hz, pulse width of 0.6 μs, average power of 1.8 mW and peak power of 3.4 W aredemonstrated. The peak power and average power of the Q-switched pulses are varied with the repetitionrate.     

高精度测量F-P标准具间距的光谱方法

利用高分辨率光谱分析仪对空气隙F P标准具透射谐振峰频率进行测量 ,然后通过直线拟合获得自由谱域 ,从而计算得出F P标准具的间距。对F P标准具间距测量的精度进行分析 ,F P标准具间距测量的相对误差为2× 10 -3 。提出了一种新颖的入射光与F P标准具垂直的精确调节方法     

新颖的双通道输出高功率掺铒光纤宽带光源

在分析L波段放大自发辐射(ASE)谱产生原理的基础上,设计出一种新颖的双级结构掺铒光纤ASE宽带光源,该光源可在两个端口分别输出高功率的C波段和L波段的ASE谱.设计将C波段ASE谱注入到掺铒光纤中作为L波段ASE谱的二次抽运源,使得L波段ASE谱功率得到了有效提高.优化光源结构参量后从两个端口分别获得了12.97 dBm和12.81 dBm的C波段和L波段ASE宽带谱.将两个输出端口组合得到了功率为15.9 dBm,泵浦转换效率达到21.6%的C+L波段超宽带ASE光源.     

级联掺磷光纤喇曼激光器的解析优化

讨论了二级级联喇曼光纤激光器的解析解和优化设计.通过引入几何平均功率、增益因子和归一化光纤有效长度,将描述泵浦光和斯托克斯光沿喇曼增益光纤分布的微分方程组简化成代数方程组,在对泵浦光采用线性传播近似后,获得了二级级联喇曼激光器的解析解.所获得的解析解同数值模拟结果吻合得很好.利用该解析解可方便和快速地讨论级联喇曼激光器的优化设计,计算不同泵浦功率下的最佳光纤长度、输出光纤光栅反射率和转换效率.泵谱功率越大,最佳光纤长度越短,最佳输出光纤光栅反射率越小.     

双正交全反射型光学电流互感器传感头精度分析

本文对双正交全反射法光学电流互感器传感头的精度进行了分析，分析结果表明采用小折射率的磁光材料以及大入射角传感头方案可以降低对加工精度的要求。同时对双正交全反射法和临界角入射法这两种设计方案中加工精度对传感器精度的影响进行了比较，得出了双正交全反射法在加工精度要求方面较临界角入射法宽松的结论。     

Micro-vibration parameters fast demodulation algorithm and experiment of self-mixing interference

Self-mixing interference （SMI） technique can be used for measuring vibration, displacement, velocity and absolute distance. In this paper, a simple demodulation algorithm for fast measuring frequency and amplitude of a simple harmonic vibration target is proposed based on the basic theoretical model of self-mixing interference effects. The simulative results show that the error between the vibration parameters which are demodulated by this algorithm and initial settings merely results from the sample rate. Further, the experimental system of self-mixing vibration measurement is built. The experimental results have a good agreement with simulation analyses. The maximum error of frequency demodulation is less than 1 Hz in our experiment.     

半导体激光束准直技术

本文根据半导体激光束的像散椭圆高斯光束特性,设计实用的半导体激光束准直系统的光学结构,并给出其参数计算的正确公式,修正了文献「５－８」中相应的公式。     

Multi-wavelength fiber source based on double-pass superfluorescent fiber source and a reflection Mach-Zehnder filter

A spectrum-sliced multi-wavelength fiber source (SS-MWFS) based on double-pass superfluorescent fiber source (SFS) with a reflection Mach-Zehnder filter (RMZF) as the reflected comb filter is demonstrated. With backward pumped configuration, MWFS with 50 wavelength channels of extinction ratio (ER) of 16.7 dB is obtained over the almost total C-band gain region. Total output power of the MWFS is 16.2 mW which shows that a power of about 0.3 mW of per channel is achieved. The SS-MWFS with forward pumped configuration is also discussed for comparing. The backward pumped configuration can provide a larger output power while only a little smaller ER than that of the forward pumped configuration.     

High-accuracy self-mixing interferometer based on multiple reflections using a simple external reflecting mirror

A self-mixing interferometer (SMI) with resolution twenty times higher than that of a conventional interferometer is developed by multiple reflections. Only by employing a simple external reflecting mirror, the multiple-pass optical configuration can be constructed. The advantage of the configuration is simple and easy to make the light re-injected back into the laser cavity. Theoretical analysis shows that the resolution of measurement is scalable by adjusting the number of reflections. The experiment shows that the proposed method has the optical resolution of approximate λ/40. The influence of displacement sensitivity gain (G) is further analyzed and discussed in practical experiments.     

单频分布布拉格反射光纤激光器及温度传感实验研究

报道利用Er∶Yb双掺杂光纤制作的单频窄线宽分布布拉格反射 (DBR)光纤激光器。在 980nm半导体激光器抽运下 ,当抽运功率为 75mW时 ,获得了输出功率为 2 3mW的单频激光 ,其中心波长为 1 5 5 7 5 2 4nm ,线宽小于 5MHz。利用制作的单频DBR光纤激光器构成光纤有源传感系统 ,进行温度传感实验研究 ,实验结果线性度很好 ,高信噪比和高输出功率使得该系统具有波长易于检测的优点