US Patent 7132204 Laser beam pattern mask and crystallization method using the same

A laser beam pattern mask includes at least one or more transmitting parts, each transmitting part having a central portion and a pair of edge portions provided to both sides of the central portion, each having a substantially triangular shape defined by a virtual boundary line between the central portion and the corresponding edge portion, an upper outside extending from an upper end of the boundary line at an acute angle, and a lower outside extending from a lower end of the boundary line at the acute angle to meet the upper outside at a rounded corner.