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简要概述了半导体泵浦碱金属激光器(DPAL)的产生背景与独特优势,以其特性为基础、应用为导向,基于国内外最新进展分析了谱线匹配、连续稳定运转和提高输出功率这三大问题,并对新型复合受激态准分子宽带泵浦碱金属激光器(XPAL)的基本原理及优缺点进行了阐述。通过对碱金属激光器现有解决思路进行对比和总结,在能级理论和缓冲气体作用机理、泵浦机理和腔结构以及高功率定标放大等方面,对未来可能的研究方向进行了展望,以期突破DPAL相关技术瓶颈,实现高能量高光束质量的红外激光输出。 相似文献
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The magnification factor for the steady-state response of a SDOF system under harmonic loading is described in many structural dynamics textbooks; the well-known analytical solution is easily obtained from the solution to the damped equation of motion for harmonic loading. The complete and steady-state solutions can differ significantly. An analytical expression for the maximum response to the complete solution (steady state plus transient) remains elusive; however, a simple analytical expression is identified herein for the undamped case. Differences in the magnification factors obtained for the two solutions are discussed. 相似文献
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Usually about one micrometer is considered the lower limit of spatial resolution (in direct space) of x‐ray diffraction. This is due as well to diffraction as to image detection. The latter problem can be addressed by image magnification. There are several efforts to achieve image magnification. One is magnification by asymmetric Bragg reflection. This is well known for many years. In the present paper the implications regarding experimental set‐up, resolution and efficiency will be considered from the experimental point of view. High magnification at good spatial resolution requires synchrotron radiation. Experiments were performed at beamlines ID19 and ID11 of the European Synchrotron Radiation Facility (ESRF). It is shown that actually a spatial resolution considerable better than one micrometer can be achieved. There are, however, some drawbacks which are related to source characteristics, synchrotron beam optics, Fresnel and Bragg diffraction. 相似文献