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711.
A 2.1 μm Cr3+, Tm3+, Ho3+ : YAG laser is operated with an output power of 20 W at 12 Hz. The laser output is successfully transmitted through a silica fibre. The laser system was designed based on the technology of an alexandrite laser oscillator. 相似文献
712.
We revisit and update the autoregressive-output-analysis method for constructing a confidence interval for the steady-state mean of a simulated process by using Rissanen's predictive least-squares criterion to estimate the autoregressive order of the process. This order estimator is strongly consistent when the output is autoregressive. The order estimator is combined with the standard autoregressive-output-analysis method to form a confidence-interval procedure. Alternatives for estimating the degrees of freedom for the procedure are investigated. The main result is an asymptotically valid confidence-interval procedure that, empirically, has good small-sample properties. 相似文献
713.
714.
波长500μm的远红外自由电子激光振荡器,是由平面被导和两个对称金属柱面镜组成的半封闭光腔.由于反射镜具有反射率,在下游镜的轴上开一个半径为Rh的圆孔来输出功率.孔耦合输出是一种简单、有效的输出方式,并可以广谱输出.缺点是抽取率随波长变化,计算很复杂.本文给出了用三维程序数值模拟结果.给出了腔内功率,输出功率,抽取率及腔镜边缘的衍射损失随小孔半径的变化.结果表明,选取适当的孔径,既可以有效地输出功率,又能保持较高的腔内功率和较纯净的腔模. 相似文献
715.
716.
Kobayashi Toshihiro; Oya Masahiro 《IMA Journal of Mathematical Control and Information》2002,19(3):279-295
In this paper we consider the design of adaptive servomechanismfor boundary control systems in the case of the input and outputoperators being collocated. An adaptive servomechanism is constructedby the concept of high-gain output feedback and the estimationmechanism of the unknown parameters for the bounded disturbances.Moreover, a controller is designed to be inverse optimal. Itminimizes a meaningful cost functional that incorporates integralpenalty on the tracking error state, the control and the parametererror. 相似文献
717.
V. V. Parshin 《International Journal of Infrared and Millimeter Waves》1994,15(2):339-348
The dielectric parameters of materials for gyrotron output windows measured in the range 65–300 GHz are given. The special attention is paid to the spread of values of the refractive index and loss tangent of dielectrics produced by different firms. The refractive index and loss tangent are measured for sapphire at the cryogenic temperatures and for boron nitride and silica glass at the temperatures 300–1000K. 相似文献
718.
有线电视系统中行波式半导体激光放大器功率特性研究 总被引:1,自引:0,他引:1
根据行波式半导体激光放大器的特点,可用输入功率的台劳级数表示放大器的输出功率,只求出级数各阶导数就可以方便地计算在多路有线电视系统中放大器引起的失真。文中出放大器的速率方程组的解,并在此基础上导出理想放大器的前三阶导数的解析表达式。 相似文献
719.
A doubly resonant ZnGeP2 (ZGP) optical parametric oscillator (OPO) pumped by a novel Tm,Ho:GdVO4 laser was demonstrated. Cryogenic Tin(5 at.-%), Ho(0.5 at.-%):GdVO4 laser with high pulse repetition frequency (PRF) of 10 kHz at 2.05 μm was employed as pumping source of ZGP OPO. The 15-mm-long ZGP crystal, 55° cut for I-type phase-matching with low absorption coefficient less than 0.05 cm^-1 at 2 μm, was placed in a piano-piano cavity with resonator length of 30 mm. The ZGP OPO generated a total combined output power of 1.2 W at 3.75 and 4.52 μm under pumping power of 5.3 W, corresponding to slope efficiency of 40% from incident 2μm laser power to midinfrared (Mid-IR) output. A widely tunable range from 3.0 to 6.5 μm was achieved by changing the crystal angle only 3.5°. 相似文献
720.
We demonstrated the highly efficient continuous wave(CW)and Q-switched infrared laser from a diodeside-pumped Nd:YAG crystal.A CW output as high as 66 W at 1319 nm was achieved under the pump power of 460 W,corresponding to a coversion efficiency of 14.3%.A maximum average power of 8.9 W of TEM00 mode was obtained in Q-switched operation at the repetition rate of 8 kHz.The performance of the laser considering the thermal lens effect induced by pump power Was also analyzed. 相似文献