Using GRIN to save 50% lens weight for an 8x rifle scope design

Starting with a literature-based design for a rifle scope, we demonstrate the potential to replace large, heavy glass lenses with polymer-based GRIN lenses with little optical penalty, while saving 50% of the lens weight in the system. Several properties of the primary design are chosen to favor manufacturability, such as leaving glass for the external surfaces and choosing polymers and GRIN geometries based on proven fabrication techniques. Compared to the reference design which weighed 154 g, the GRIN-substituted design weighed 78 g while maintaining visually constant performance from 0-40°C.