展宽器元件失调及带通分析

通过光线追迹法给设计的反射式单光栅展宽器建立了一个数学计算模型。利用这个数学模型计算和分析了元件失调对反射式单光栅展宽器二阶色散量和输出光束发散角的影响，并考虑了反射式单光栅展宽器中衍射光栅和球形凹面镜的尺寸与展宽器带通的关系。发现当平面反射镜M1的纵向偏离角为0．2°时．展宽器的二阶色散量最大，偏离角大于或小于0．2°时，展宽器的二阶色散量随之减小；得到了元件失调会增加输出光束发散角的结论；并发现展宽器中衍射光栅和球形凹面镜尺寸的有限大小对带通有限制作用。提出了利用反射镜M1纵向的适当偏离增大展宽器二阶

Phase-shifting apodizers for increasing focal depth

We propose the use of a phase-shifting apodizers to increase focal depth, and we study the axial and radial behavior of this kind of apodizer under the condition that the axial intensity distribution is optimized for high focal depth. (C) 2002 Optical Society of America.

Fluorescence lifetime increasing with F- ions into ytterbium-doped germanium-lead-tellurite glasses

The effects of F- ions in a germanium-lead-tellurite glass system oil the spectral and potential laser properties of the Yb3+ are investigated. The absorption spectra, lifetimes, the emission cross-sections and the minimum pump intensities of the glass system with and without F- ions have been measured and calculated. The results show that the fluorescence lifetime and the minimum pump intensity of Yb3+ ions increase evidently, which indicates that germanium lead-oxyfluoride tellurite glass is a promising laser host matrix for high power generation. FT-IR spectra were used to analyse the effect of F- ions on OH- groups in this glass system. Analysis demonstrates that addition of fluoride removes the OH- groups and results in improvement of fluorescence lifetime of Yb3+.

双频激光干涉仪的最大可测量速度研究

现代制造业对双频激光干涉仪的最大可测量速度提出了越来越高的要求。最大可测量速度是双频激光干涉仪的一项重要指标，它主要受双频激光光源所输出的频差、干涉仪的光学结构以及电子带宽等因素的限制。本文从理论和实验两方面对干涉仪的最大可测量速度进行了研究，搭建了基于自由落体运动的实验装置。实验结果表明，实际最大可测量速度略低于其理论值。另外，文中还分析了上述三种因素对最大可测量速度的影响。实验装置和结果可供工业应用提供参考。