Patent attributes
A plastic lens barrel includes an object-end portion, an image-end portion and a tube portion. The object-end portion has an object-end outer surface, an object-end opening and an object-end inner surface, wherein one end of the object-end inner surface is connected to the object-end outer surface and surrounds the object-end opening. The image-end portion has an image-end outer surface and an image-end opening. The tube portion connected object-end portion and the image-end portion, and includes a plurality of tube inner surfaces. At least one of the tube inner surfaces and the object-end inner surface includes a plurality of annular convex structures. Each of the annular convex structures surrounds a central axis of the plastic lens barrel. A cross-sectional plane of each annular convex structure passing through the central axis includes a peak point and two valley point.