Patent ID: 9725269
Date: 2017-08-08
CPC Classifications: B65H

Claim:
1. A sheet winding structure having a winding core having an outer surface for winding an optical sheet, wherein the outer surface of the winding core comprises a recess thereon, wherein the recess is formed by a sidewall and a bottom surface connected to the sidewall, wherein the optical sheet comprises a beginning portion disposed in the recess, wherein the beginning portion comprises a first major surface disposed on the bottom surface of the recess, a second major surface opposite to the first major surface and a thickness surface facing the sidewall of the recess, wherein the length of the sidewall of the recess is less than 0.35 millimeter and the bottom surface of the recess is a flat surface for placing the beginning portion of the optical sheet thereon so as to reduce the indentation transfer of the optical sheet winded over the outer surface of the winding core.