Hot crimping structure and method for fixing a lens to a lens frame, and hot crimping tool therefor

摘要

A hot crimping structure for fixing at least one lens element to a lens frame made of synthetic resin, the lens element being accommodated in a lens holder opening of the lens frame, a portion of the lens frame being crimped by heat to serve as a crimped edge which lies on a surface of the lens element adjacent to a rim of the lens element. The lens frame includes an outward expansion surface which extends outwards from a close vicinity of the rim of the lens element. A hot crimping tool is brought into contact with the outward expansion surface to form a recess on the outward expansion surface by heat, to thereby produce the crimped edge by movement of melting synthetic resin which is melted due to the formation of the recess.