Global Polycrystalline Transparent Ceramics Market By Type (Sapphire, Yttrium Aluminum Garnet, Aluminum Oxynitride, and Spinel), By Application (Optics & Optoelectronics, Aerospace; Defense & Security, Mechanical/Chemical, Sensors & Instrumentation, Healthcare, Consumer goods/electronics, and Consumer goods/electronics), By Region, and Key Companies - Industry Segment Outlook, Market Assessment, Competition Scenario, Trends and Forecast 2019-2028