Trends in Optical Materials

The trend in optical materials can be easily and accurately predicted -- optical materials will be better, cheaper, and more complex in the future. This summary may be too simple and perhaps all of these trends will not be true of all optical material. However, recent experience shows that significant progress has been made in preparing high quality optical materials. Especially impressive are the solid state laser host materials which include single crystals and glasses and optical components for infrared lasers fabricated from alkali halides, alkaline earth fluorides, sapphire, and CVD ZnSe. Demands for low cost molded optics for consumer products have lead to the expanded use of plastics and the development of precision molding processes. Similar trends are developing for infrared optics; for example, the pressing of lenses. Aspheric surfaces machined by single point diamond turning are an example of the improved capability for producing complex components. Sol gel, MBE techniques for the production of graded index antireflection coatings, surface strengthening of optical materials and the production of gradient index optics are emerging materials processes that will probably play a growing role in the fabrication of optical components.