METHOD OF FORMING GLASS OPTICAL ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide a method of forming cylindrical type lens made of glass which permits precise control of the diameter of the cylindrical type lens made of the glass in molding and permits changing, if any, of the amount of a perform changes to some extent. SOLUTION: A split type sleeve which can be exactly controlled in the external diameter and run-out to be obtainable in the final are included in a forming aperture without precisely controlling the amount of the perform. The split type sleeve comprises a pair of molded sleeve pieces.