The reflected light amount acquiring process acquires the reflected light amount of a laser beam with which a color changeable layer is irradiated from at least one irradiation position included in a predetermined drawing determination area, where the color changeable layer is formed on a label side of an optical disc and changes in color due to heat or light. The operation process compares the reflected light amount acquired from the at least one irradiation position by the reflected light amount acquiring process with a predetermined threshold value to determine whether or not the drawing determination area is suitable for formation of a visible image.