US Patent 11772324 Three-dimensional printing with reciprocal feeding of polymerizable liquid

Described herein are methods, systems and apparatus (including associated control methods, systems and apparatus), for the production of a three-dimensional object by “bottom up” additive manufacturing, in which a carrier is vertically reciprocated with respect to a build surface, to enhance or speed the refilling of the build region with a solidifiable liquid. In preferred (but not necessarily limiting) embodiments, the three-dimensional object is produced from a liquid interface by continuous liquid interface production (i.e., “CLIP”).