Abstract: A hot runner nozzle includes a nozzle body configured to define a flow path of molten resin, and a cover member arranged at a circumference of a tip portion of the nozzle body. The cover member includes a first engagement portion being arranged on a part of an outer periphery and configured to engage with a mold and/or a second engagement portion being arranged on a part of an inner periphery and configured to engage with the nozzle body.

Abstract: A hot runner nozzle includes a nozzle body configured to define a flow path of molten resin, and a cover member arranged at a circumference of a tip portion of the nozzle body. The cover member includes a first engagement portion being arranged on a part of an outer periphery and configured to engage with a mold and/or a second engagement portion being arranged on a part of an inner periphery and configured to engage with the nozzle body.

Abstract: An injection mold includes a cavity formed by a plurality of members including at least a convex surface member and a concave surface member, and a gate formed by a plurality of members including at least a flash formation preventing member. One of the members forming the gate is disposed so as to be adjacent to one of the members forming the cavity, and is pressed against the adjacent member forming the cavity by a pressure of injected resin.

Abstract: A dome-shaped cover having a high optical performance in which formation of a weld mark is suppressed. The dome cover includes a hemispherical portion, a collar portion, and a cylindrical portion provided between the hemispherical portion and the collar portion, and the cylindrical portion has a thin portion recessed from an outer surface of the cylindrical portion.

Abstract: An optical part includes a lens and a holder having the lens fixed thereto. The holder is a cylindrical member including a front surface, a back surface, an outer peripheral surface, and an inner peripheral surface. The back surface contacts the lens, and part of the inner peripheral surface penetrates the lens.

Abstract: A composite plastic lens including: a lens having a convex surface, a lens back surface, and a protrusion formed on at least part of an periphery; and a holder, the lens and the holder being molded integrally, wherein the cross-sectional shape of at least part of the lens including an optical axis on the convex surface side is such that a profile line on the convex surface side is curved in a direction getting closer to the lens back side as it goes from the optical axis side toward a turning point out of an optical effective area, and the cross sectional shape of the protrusion is inverted from the turning point out of the optical effective area toward the periphery in a direction away from the lens back surface, and the holder is fitted to the protrusion so as to include the turning point and is molded integrally on the peripheral side of the resin lens.

Abstract: A portion of a holder is in contact with a lens surface, a holding portion configured to hold a lens in the holder is provided, and a mold shrinkage factor of a material that forms the holder is smaller than a mold shrinkage factor of a material that forms the lens by no less than 0.3%.

Abstract: A portion of a holder is in contact with a lens surface, a holding portion configured to hold a lens in the holder is provided, and a mold shrinkage factor of a material that forms the holder is smaller than a mold shrinkage factor of a material that forms the lens by no less than 0.3%.

Abstract: A composite plastic lens including: a lens having a convex surface, a lens back surface, and a protrusion formed on at least part of an periphery; and a holder, the lens and the holder being molded integrally, wherein the cross-sectional shape of at least part of the lens including an optical axis on the convex surface side is such that a profile line on the convex surface side is curved in a direction getting closer to the lens back side as it goes from the optical axis side toward a turning point out of an optical effective area, and the cross sectional shape of the protrusion is inverted from the turning point out of the optical effective area toward the periphery in a direction away from the lens back surface, and the holder is fitted to the protrusion so as to include the turning point and is molded integrally on the peripheral side of the resin lens.

Abstract: An injection mold includes a cavity formed by a plurality of members including at least a convex surface member and a concave surface member, and a gate formed by a plurality of members including at least a flash formation preventing member. One of the members forming the gate is disposed so as to be adjacent to one of the members forming the cavity, and is pressed against the adjacent member forming the cavity by a pressure of injected resin.

Abstract: A composite plastic lens including: a lens having a convex surface, a lens back surface, and a protrusion formed on at least part of an periphery; and a holder, the lens and the holder being molded integrally, wherein the cross-sectional shape of at least part of the lens including an optical axis on the convex surface side is such that a profile line on the convex surface side is curved in a direction getting closer to the lens back side as it goes from the optical axis side toward a turning point out of an optical effective area, and the cross sectional shape of the protrusion is inverted from the turning point out of the optical effective area toward the periphery in a direction away from the lens back surface, and the holder is fitted to the protrusion so as to include the turning point and is molded integrally on the peripheral side of the resin lens.

Abstract: An optical part includes a lens and a holder having the lens fixed thereto. The holder is a cylindrical member including a front surface, a back surface, an outer peripheral surface, and an inner peripheral surface. The back surface contacts the lens, and part of the inner peripheral surface penetrates the lens.

Abstract: A center-portion molding member having a center-portion transfer shape surface and a side wall surface is inserted and fitted in a frame-portion molding member having a frame-portion transfer shape surface to form a part of a cavity. The center-portion molding member has a groove portion in the side wall surface. The groove portion protrudes from the frame-portion transfer shape surface. Before injected resin transfers a shape of the center-portion transfer shape surface, the side wall surface of the center-portion molding member is sealed with the resin to form, between the center-portion transfer shape surface and the resin, a space in which gas is confined.

Abstract: A dome-shaped cover having a high optical performance in which formation of a weld mark is suppressed. The dome cover includes a hemispherical portion, a collar portion, and a cylindrical portion provided between the hemispherical portion and the collar portion, and the cylindrical portion has a thin portion recessed from an outer surface of the cylindrical portion.

Abstract: A composite plastic lens including: a lens having a convex surface, a lens back surface, and a protrusion formed on at least part of an periphery; and a holder, the lens and the holder being molded integrally, wherein the cross-sectional shape of at least part of the lens including an optical axis on the convex surface side is such that a profile line on the convex surface side is curved in a direction getting closer to the lens back side as it goes from the optical axis side toward a turning point out of an optical effective area, and the cross sectional shape of the protrusion is inverted from the turning point out of the optical effective area toward the periphery in a direction away from the lens back surface, and the holder is fitted to the protrusion so as to include the turning point and is molded integrally on the peripheral side of the resin lens.