Patent ID: 8228610

Claim:
A lens injection mold for injection molding of the plastic lens having an effective aperture portion being an optical surface of the lens, and a rib portion being a circumferential portion of the lens, having a portion in contact with an inner circumferential portion of a barrel, and including three or more concave portions in an outer circumferential portion thereof, the effective aperture portion and the rib portion being shaped as concentric circles having the same central axis, and the concave portions being positioned to be symmetrical with respect to the central axis and having the same size and shape, the lens injection mold comprising: an upper mold and a lower mold; a cavity provided in the upper mold or the lower mold and having a shape corresponding to the rib portion having the concave portions in order to form the rib portion; and an upper core and a lower core disposed to be movable inside the upper mold and the lower mold and having an upper tip portion and a lower tip portion, respectively, the tip portions having a shape corresponding to the effective aperture portion such that the effective aperture portion is created by pressing injection liquid.