Apparatus and method for molding glass optical elements

An apparatus for molding glass lens elements from glass preforms comprising:

• (a) a first mold element supported in a first sleeve segment;
• (b) a second mold element residing in a second sleeve segment, the first sleeve segment and the first mold element being movable toward the second sleeve segment and second mold element;
• and
• (c) a mold cavity defined by the first mold element, the second mold element, the first sleeve segment, and the second sleeve section when the first sleeve segment is moved to abut the second sleeve segment, the mold cavity including a lens chamber and an annular channel projecting from the lens chamber.

An apparatus for molding glass lens elements from glass preforms comprising:

• (a) at least two first mold elements supported in individual bores in a first sleeve segment;
• (b) at least two second mold elements residing in individual bores in a second sleeve segment, the first sleeve segment and the first mold elements being movable toward the second sleeve segment and second mold elements;
• and
• (c) at least two mold cavities, each of the at least two mold cavities defined by one of the at least two first mold elements, one of the at least two second mold elements, one of the bores in the first sleeve segment, and an aligning one of the at least two bores in the second sleeve segments when the first sleeve segment is moved to abut the second sleeve segment, each of the at least two mold cavities including a lens chamber and an annular channel projecting from the lens chamber.

A method for molding glass lens elements comprising the steps of:

• (a) placing a glass preform on a first mold surface of a first mold element, the first mold element residing in a first sleeve segment;
• (b) elevating the temperature the glass preform, the first mold element, the first sleeve segment, a second mold element, and a second sleeve segment to at least a glass transition temperature of the glass preform, the second mold element residing in the second sleeve segment;
• (c) moving the second mold element and second sleeve segment toward the first mold element and first sleeve segment to form a mold cavity, the mold cavity including a lens chamber and an annular channel projecting from the lens chamber;
• (d) compressing the glass preform in the mold cavity to form a glass lens element;
• and
• (e) flowing excess glass from the glass preform into the annular channel.