Plastic lens and method of making a plastic lens
AssigneeFuji Photo Optical Co., Ltd.
InventorsYoshimitsu Nomura, Masaaki Fukuda, Takashi Ito, Kaneyoshi Yagi
Life of this patent
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Abstract
A plastic lens which is easy to mold and has favorable optical precision. This plastic lens has a flange at the outer periphery of an optically functioning portion, a part of the peripheral surface of the flange being provided with a gate-positioning projection, and a side face of the gate-positioned projection including a cut-off portion.
Claims5
A plastic lens comprising:
- an optically functioning portion;
- a flange surrounding said optically functioning portion;
- a gate-positioned projection on a part of a surface of said flange;
- and
- a cut-off portion located at a side face of said gate-positioned projection and formed by cutting off a superfluous part molded at an injection-gate.
A method of making a plastic lens, said method comprising molding said plastic lens by injecting a molten resin into a molding die having a cavity, through an injection-gate, the cavity comprising a molding space for forming an optically functioning portion, a molding space for forming a flange surrounding said optically functioning portion, and a molding space for forming a gate-positioned projection on a part of a surface of said flange, said injection-gate communicating with said molding space for forming said gate-positioned projection.
Dependencies are inferred from the claim text.