光学玻璃中Pt闪点的结构特征及其形成机理

Structure and formation mechanism of Pt spangle in optical glass

SiO_2-B_2O_3-Ta_2O_5-ZrO_2-Na_2O系统光学玻璃因具有较大的相对部分色散偏离值、良好化学稳定性和可加工性等特点而备受关注。作者采用分光光度计、光学显微镜、扫描电镜及能谱等方法系统研究了光学玻璃中Pt闪点结构特征及其形成机理。Pt坩埚制备的光学玻璃在紫外区存在明显吸收,且吸收曲线向长波方向移动,这是由于玻璃中Pt^(4+)离子吸收峰所致。Pt闪点存在形式多样,大小不一,尺寸主要在20μm以下。SiO_2-B_2O_3-Ta_2O_5-ZrO_2-Na_2O系统玻璃中Pt闪点的影响因素主要有组分中高含量高键强离子Ta^(5+)和Zr^(4+)、低玻璃粘度和熔体降温处理等。

Optical glass for SiO2-B2O3-Ta2O5-ZrO2-Na2O system has attracted much attention because of its high deviation of the relative partial dispersion,excellent transmission and workability.The structure and formation mechanism of Pt spangle in optical glass were investigated in detail by spectrophotometer,optical microscope,scanning electron microscope（SEM）and energy dispersive spectrometer（EDS）.The optical glass fabricated in Pt crucible has evident UV absorption due to the existence of Pt4＋.Pt spangle in optical glass has various shapes and sizes,but its sizes are smaller than 20μm.For SiO2-B2O3-Ta2O5-ZrO2-Na2O system glass,the high content of Ta5＋ and Zr4＋,low viscosity and cooling treatment are major factors to control the formation of Pt spangle.