An additive manufacturing apparatus comprising: a laser beam generator operable to generate at least one laser beam; a working surface including a build surface disposed along an X-Y plane and spaced apart from the laser beam generator; a first optical element rotatably supported in a housing and disposed along a travel path of the at least one laser beam, between the laser beam generator and the build surface, the first optical element continuously rotatable about a beam steering axis perpendicular to the build surface; a second optical element rotatably supported in the housing and disposed adjacent to the first optical element along the travel path of the at least one laser beam, the second optical element continuously rotatable about the beam steering axis independently of the first optical element; and a controller to manage relative and absolute rotational speeds of the first and second optical elements (46, 48), such that the first and second optical elements (46, 48) redirect the at least one laser beam from the beam generator to form a continuous nonlinear scanning path along and over an entirety of the build surface without deactivating the laser beam generator, the build surface including a perimeter portion, a transition portion, and a core portion; wherein: the first optical element comprises a first beam input surface and a first beam output surface each intersected by the beam steering axis, wherein a difference between the first beam input angle and the first beam output angle defines a first beam deflection angle relative to the beam steering axis; wherein the second optical element comprises a second beam input surface and a second beam output surface each intersected by the beam steering axis; characterized in that the first beam output surface is parallel to the second beam input surface and the X-Y plane. a laser beam generator operable to generate at least one laser beam; a working surface including a build surface disposed along an X-Y plane and spaced apart from the laser beam generator; a first optical element rotatably supported in a housing and disposed along a travel path of the at least one laser beam, between the laser beam generator and the build surface, the first optical element continuously rotatable about a beam steering axis perpendicular to the build surface; a second optical element rotatably supported in the housing and disposed adjacent to the first optical element along the travel path of the at least one laser beam, the second optical element continuously rotatable about the beam steering axis independently of the first optical element; and a controller to manage relative and absolute rotational speeds of the first and second optical elements (46, 48), such that the first and second optical elements (46, 48) redirect the at least one laser beam from the beam generator to form a continuous nonlinear scanning path along and over an entirety of the build surface without deactivating the laser beam generator, the build surface including a perimeter portion, a transition portion, and a core portion; wherein: the first optical element comprises a first beam input surface and a first beam output surface each intersected by the beam steering axis, wherein a difference between the first beam input angle and the first beam output angle defines a first beam deflection angle relative to the beam steering axis; wherein the second optical element comprises a second beam input surface and a second beam output surface each intersected by the beam steering axis; characterized in that the first beam output surface is parallel to the second beam input surface and the X-Y plane. a first optical element rotatably supported in a housing and disposed along a travel path of the at least one laser beam, between the laser beam generator and the build surface, the first optical element continuously rotatable about a beam steering axis perpendicular to the build surface; a second optical element rotatably supported in the housing and disposed adjacent to the first optical element along the travel path of the at least one laser beam, the second optical element continuously rotatable about the beam steering axis independently of the first optical element; and a controller to manage relative and absolute rotational speeds of the first and second optical elements (46, 48), such that the first and second optical elements (46, 48) redirect the at least one laser beam from the beam generator to form a continuous nonlinear scanning path along and over an entirety of the build surface without deactivating the laser beam generator, the build surface including a perimeter portion, a transition portion, and a core portion; wherein: the first optical element comprises a first beam input surface and a first beam output surface each intersected by the beam steering axis, wherein a difference between the first beam input angle and the first beam output angle defines a first beam deflection angle relative to the beam steering axis; wherein the second optical element comprises a second beam input surface and a second beam output surface each intersected by the beam steering axis; characterized in that the first beam output surface is parallel to the second beam input surface and the X-Y plane.