Global Photochromic Lenses Market By Type (Glass, Standard Plastic (1.53 Coat and Uncoat), Mid-Index Plastic (1.53 to 1.65), High-Index Plastic (Above 1.65), and Polycarbonate), By Application (Children, Outdoor Activities, and People with Light Sensitivity), By Region and Key Companies - Industry Segment Outlook, Market Assessment, Competition Scenario, Trends and Forecast 2019–2028