Abstract: An apparatus and the method of its operation for rapid prototyping of a three-dimensional object which includes a radiant energy source of a wide beam of radiant energy of suitable intensity and wavelength for curing a layer of photo-curable resin contained in an open vat, a spatial light modulator (SLM) having an array of pixel elements which are individually digitally controllable by a computer, for modulating the radiant energy beam projected from the radiant energy source on a pixel by pixel basis, to form a series of time sequential images of the cross-sectional laminae of the object, an optical system for focusing each image formed by the SLM, one at a time, onto successive layers of photo-curable resin for predetermined exposure times to thereby form stacked laminae of cured resin, each lamina of cured resin being in the shape of a different one of the cross-sectional laminae, and a piston support for lowering each lamina of cured resin after it is formed by the SLM and for depositing a layer of resin