A continuous additive fabrication system, comprising: a bath of photopolymer resin; a light source assembly comprising a light source and a motorized variable aperture, the light source assembly operable to generate a focus point in the bath of photopolymer resin, the shape of the focus point at a curing plane within the bath of photopolymer resin corresponding to the shape of the motorized variable aperture; a platform configured to support cured polymer comprising a build object; a drive mechanism coupled to at least one of the platform and the light source assembly, the drive mechanism configured to continuously move the curing plane through the bath of photopolymer resin; wherein the system comprises a processor configured such that a size and/or shape of the motorized variable aperture is changed while the curing plane is continuously moved through the bath of photopolymer resin, wherein the processor is configured such that the curing plane is continuously moved through the bath of photopolymer resin by continuously moving the light source assembly vertically up and away from a surface of the photopolymer resin, thereby moving the curing plane vertically through the photopolymer resin towards the surface, wherein a rate of the change to the size and/or shape of the motorized variable aperture is synchronized with a speed of the movement of the light source assembly, or the curing plane is continuously moved through the bath of photopolymer resin by continuously changing an optical power of the light source assembly to thereby move the curing plane vertically through the photopolymer resin towards a surface of the photopolymer resin and a rate of the change to the size and/or shape of the motorized variable aperture is synchronized with a speed at which the curing plane is continuously moved vertically through the photopolymer resin. a bath of photopolymer resin; a light source assembly comprising a light source and a motorized variable aperture, the light source assembly operable to generate a focus point in the bath of photopolymer resin, the shape of the focus point at a curing plane within the bath of photopolymer resin corresponding to the shape of the motorized variable aperture; a platform configured to support cured polymer comprising a build object; a drive mechanism coupled to at least one of the platform and the light source assembly, the drive mechanism configured to continuously move the curing plane through the bath of photopolymer resin; wherein the system comprises a processor configured such that a size and/or shape of the motorized variable aperture is changed while the curing plane is continuously moved through the bath of photopolymer resin, wherein the processor is configured such that the curing plane is continuously moved through the bath of photopolymer resin by continuously moving the light source assembly vertically up and away from a surface of the photopolymer resin, thereby moving the curing plane vertically through the photopolymer resin towards the surface, wherein a rate of the change to the size and/or shape of the motorized variable aperture is synchronized with a speed of the movement of the light source assembly, or