| 摘要 |
The procedure consists of forming a disc (12) of a thermoplastic polymer material by injection molding between female (13) and male (14) components shaped to create the outer and inner surfaces of the lens. The male component has a central region (17) with a convex surface, a peripheral rib (19) to make a web (21), and a peripheral groove (22) to make a crown ring (23). The inner surface (27) of the disc is machine to give the desired optical correction, and the crown ring is removed from the web, part of which is retained to fix the lens to a frame. |
