排序方式: 共有78条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
Yb:YAG晶体中的荧光浓度猝灭现象 总被引:4,自引:0,他引:4
在Yb:YAG晶体中发现浓度猝灭现象,对猝灭机制进行了分析研究,指出退火前晶体的荧光浓度猝灭现象主要由Yb^2+、色心和由此产生的晶格畸变所致高掺杂浓度时痕量稀土杂质离子的存在也将导致浓度猝灭,确定了Yb:YAG晶体中Yb^3+的理想掺杂浓度。 相似文献
5.
6.
7.
8.
A digital holographic method that can be used for the simultaneous measurement of slopes of a deformed object in different directions is described in this paper. In this method, two holograms are recorded numerically under the normal and deformed states of the specimen, and two object waves are numerically calculated from these two holograms. The slopes corresponding to different directions are measured by superposing the two object waves with appropriate shifts. It is a superior method in regard to the simple experiment setup, the flexibility in handing the data, and the high quality phase maps. 相似文献
9.
1 Introduction Stressanalystsareofteninterestedinthederivativesofthedisplacementratherthanthedisplacementitself ,becausestrainsandhencestressesarefirst orderderivativesofdisplacement.Thederivativescanbeobtainednumericallyfromthedisplacementdatabutthep… 相似文献
10.
大气湍流对天文望远镜光电导行精度的影响 总被引:1,自引:0,他引:1
讨论了由大气湍流造成的望远镜导行误差,这一误差将给望远镜光电导行的精度带来较大影响。其中使用单点源目标的导行精度受限于大气相干长度和大气相干时间,而多点源目标及面源的导行精度还与湍流随高度的变化有关。通过分析和仿真(数值模拟)结果表明,现代天文观测必须考虑大气湍流对光电导行精度的影响。通过延长曝光时间可以有效降低湍流大气的影响,同时也降低了光电导行的反馈控制频率。当导行信标为多星或面源则可在一定程度上降低高层大气湍流带来的光电导行误差,从而可以适度减少光电导行曝光时间,提高其反馈控制频率。 相似文献