Patent attributes
An apparatus for forming a three-dimensional article is provided, comprising means for providing a predetermined amount of powder, a powder distributor, means for directing an energy beam over a first powder layer causing it fuse in selected locations according to a model, a camera for capturing at least one image of a shape of at least one portion of the predetermined amount of powder that has yet to be initially distributed, the at least one image being captured prior to distribution of an entirety of all portions of the predetermined amount of powder over the surface, and means for comparing at least one value of at least one parameter in the image detected with a corresponding reference parameter value, wherein the at least one parameter is associated with the shape of the powder that has yet to be initially distributed.
