Effect of alkali and alkaline earth fluoride introduction on thermal stability and structure of fluorophosphate glasses

The thermal stability and structure of RF-RF2-AIF(3)-Al(PO3)(3) fluorophosphate glasses were investigated. Analyses of infrared absorbance spectra and Raman spectra reveal that with increasing number of alkali and alkaline earth fluoride components, the sum of P-O-P bond and O-P-O bond increases and glass network is strengthened. Consequently, the inhibition to nucleation and crystallization processes is improved, which is proved by the increment of thermal stability factors AT and S determined by differential scanning calorimetry. In addition, it was found that LiF has poor ability to form glass in univalent alkali fluorides and MgF2 has comparative strong ability to form glass in bivalent alkaline earth fluorides. (c) 2006 Published by Elsevier B.V.

倍频波长分离膜半波孔的消除

指出了膜料色散、膜层折射率非均匀性以及膜厚控制误差积累等是导致半波孔产生的几个因素，其中膜层厚度周期性误差积累和敏感层厚度误差是导致半波孔的主要因素，还指出了半波孔的大小与膜系结构有关。借助计算机做了相应的数值计算，并从理论上进行了深入分析。针对这些因素采取相应的措施，设计和制备了倍频波长分离膜，有效地消除了半波孔。并给出了理论和实验光谱曲线，二者有很好的一致性。