基于光纤环形镜的掺磷光纤拉曼激光器

报道了一种由宽带光纤环形镜(FLM)作为腔反射元件的法布里-珀罗腔掺磷光纤拉曼激光器(RFL),并与使用窄带光纤布拉格光栅(FBG)作为高反镜的腔结构进行了对比研究。研究结果表明,使用宽带FLM替代FBG仍可实现掺磷RFL的窄带激光输出,并且可有效避免拉曼激光从高反镜端的泄漏。在相同的输出镜反射率情况下,使用FLM作为高反镜比使用FBG作为高反镜具有更低的振荡阈值和更高的光-光转换效率。当抽运功率为9.45W时,拉曼激光(1.24μm)输出功率为4.31W,激光器斜效率和光-光转换效率分别为57.9%和45.6%

一种多功能智能医疗床的设计与仿真分析

针对人口老龄化带来的市场需求问题，基于马斯洛需求理论和人机工程学设计了一种多功能智能医疗床。根据市场调研和数据分析，确定驱动与停止功能、姿势变化功能、人机操作界面、辅助生理功能，并设计相应机构。基于Pro/E软件设计医疗床的三维模型，采用Matlab进行理论计算，利用Adams软件对主要机构进行仿真和运动学分析，利用ANSYS软件对智能医疗床的关键零部件进行静力学分析。研究结果证明，医疗床方案可行，满足强度和刚度条件，变形角度达到设计要求，参数设计合理，满足人体工程学

Large-energy, wavelength-tunable, all-fiber passively Q-switched Er:Yb-codoped double-clad fiber laser with mono-layer chemical vapor deposition graphene

National Natural Science Foundation of China [61275050, 61177044]; Natural Science Foundation of Fujian Province of China [2011J01370]; Specialized Research Fund for the Doctoral Program of Higher Education [20120121110034]; Fundamental Research Funds for the Central Universities [2011121048]We demonstrate a large-energy, wavelength-tunable, all-fiber passively Q-switched Er:Yb-codoped laser using a mono-layer chemical vapor deposition (CVD) graphene saturable absorber (SA). By exploiting the large laser gain of Er:Yb double-clad fiber and optimizing the coupling ratio of the output coupler, not only can the mono-layer CVD graphene SA be protected from oversaturation and thermal damage, but also a large pulse energy up to 1.05 mu J (corresponding to the average output power of 25.6 mW) is thus achieved. Using a tunable fiber Fabry-Perot filter, stable Q-switched pulses can operate with a tunable range from 1530.97 to 1546.92 nm, covering a wavelength range of similar to 16 nm. The Q-switching states at the different lasing wavelengths have been observed and recorded. The Q-switched repetition rate and the pulse duration (with the minimum one of 2.6 mu s) have been characterized as well. This is, to the best of our knowledge, the largest pulse energy from an all-fiber graphene Q-switched laser. (C) 2014 Optical Society of Americ

Passive synchronization of 106- and 153-μm fiber lasers Q-switched by a common graphene SA

We demonstrate the passive synchronization of two large-energy Q-switched all-fiber lasers, operating at 1.06 and 1.53 μm, by sharing a common monolayer graphene Q-switcher. The fiber-compatible Q-switcher is constructed by transferring a monolayer CVD graphene nanosheet onto a fiber ferrule. By exploiting the broadband saturable absorption of graphene and optimizing the cavity designs, both the largeenergy Q-switched Yb and Er/Yb double-clad fiber lasers are successfully synchronized. The Q-switching synchronization can be realized in the broad repetition-rate range of 9-20 kHz by adjusting the pump powers of the two lasers. The maximum pulse energies are 5.30 μJ at 1.06 μm and 1.20 μJ at 1.53 μm, respectively, which is, to the best of our knowledge, the largest pulse energy obtained from graphene Q-switched all-fiber laser. ? 1989-2012 IEEE