Lamination molding method and lamination molding system

A lamination molding system, comprising:

• a computer aided manufacturing device that creates a project file in which a command according to lamination molding is defined;
• and
• a lamination molding apparatus that performs the lamination molding based on the project file, wherein
• the lamination molding apparatus comprises:
• a material layer former that forms a material layer on a predetermined molding region;
• and
• an irradiation device that has a laser source generating laser beams and n scanners scanning the laser beams, wherein n is an integer equal to or greater than 2, and irradiates the laser beams to a predetermined irradiation region of the material layer to form a solidified layer;
• and
• during a creation of the project file, the computer aided manufacturing device
• divides the irradiation region to 2n-1 or more divided regions by a plurality of first dividing lines in a manner that irradiation time of each of the divided regions to which the laser beams are simultaneously irradiated becomes equal, and
• decides an irradiation order of the divided regions in a manner that the laser beams are simultaneously irradiated to the divided regions that are not adjacent, and the laser beams are not simultaneously irradiated to the divided regions that are adjacent.