Polishing of Sapphire for Optical Applications

目前用于制造蓝宝石的工艺引入了许多 在所生长的蓝宝石中的缺陷例如管芯痕迹和生长伪像 空格.因此，这些材料在用于光学之前需要抛光。第一阶段的目标是开发一种高质量、高速度、低成本的抛光蓝宝石光学器件的技术。目前用于抛光蓝宝石的两种方法是：机械和机械化学，这两种方法都涉及刮擦，研磨和使用磨料，如金刚石或胶体二氧化硅。这些方法是昂贵的，因为需要长时间的抛光。此外，由于施加机械压力，在抛光界面处产生热量，留下影响光学性能的缺陷。阶段I将通过使用双阶段非接触方法来移除蓝宝石的平面层，从而在平坦和平坦两种情况下实现埃量级的表面粗糙度来建立概念验证。 弯曲的空白。将对抛光的 样本并与处理参数相关联。在第二阶段，我们 我建议将这项技术推广到光学圆顶。该技术还可以用于涉及光学部件的其它应用，所述光学部件例如激光腔镜、激光束镜、透镜、具有高光学透射的窗口、软光盘驱动器和磁盘驱动器中的部件。 **

9360761 Sudarshan Current processes for manufacturing sapphire introduce a number of defects such as die marks and growth artifacts in the as-grown sapphire blank. Thus these materials will need to be polished prior to use in optics. The objective of this Phase I effort is to develop a high quality, high speed, cost effective technique for polishing sapphire based optics. The two methods currently used for polishing sapphire are: mechanical and mechanochemical, both of which involve scraping, grinding and using abrasives such as diamond or colloidal silica. These methods are expensive because of the long times required for polishing. Further, due to the application of mechanical pressure, heat is generated at the polishing interface leaving behind defects that affect optical performance. Phase I will establish the proof of concept by using a dual stage non-contact method to remove planar layers of the sapphire thus achieving surface roughness on the order of angstroms in both flat and curved blanks. Optical characterization will be performed on the polished samples and correlated to the processing parameters. In Phase II, we propose expanding this technique for optical domes. This technique can also be used for other applications involving optical components such as laser cavity mirrors, laser beam mirrors, lenses, windows with high optical transmission, components in floptical disk drives and magnetic disk drives. **