Enhanced resolution DLP projector apparatus and method of using same
A DLP projector apparatus ( 10 ) for projecting a monochromatic display comprising a plurality of monochromatic light sources ( 111 - 113 ). The DLP projector ( 10 ) being adapted to radiate from each micromirror of its DMD chip ( 100 ) an image comprising a plurality of radiated locations which are shifted with respect to each other. The DLP projector apparatus ( 10 ) comprising a controller unit that is adapted to control the radiation from the plurality of light sources ( 111 - 113 ) to the image according to a radiation scheme in an object production file. The DLP projector apparatus ( 10 ) is also provided with an imaging table ( 240 ) that is adapted to be moved in a plane perpendicular to an imaging beam of the DLP projector apparatus ( 10 ). The movements of the table are coordinated and synchronized with the imaging scheme of the DLP projector apparatus ( 10 ). The imaging scheme and the movements of the table are controlled according to a radiation scheme in an object production file.
1. A method of building three dimensional (3D) objects in an additive manufacturing printing system having a DLP projector of a first resolution, the DPL projector including at least three light sources radiating monochromatic light beams having variance that does not exceed 50 nm wavelength, the method comprising:
positioning a production plane off-focus with respect to the DLP projector to define a defocused image plane;
depositing a layer of radiation-curable flowable building material on the defocused image plane of the DLP projector apparatus, the layer being curable by radiation from said DLP projector apparatus;
selectively radiating onto said layer of radiation-curable flowable building material monochromatic light beams from at least one of at least three light sources according to data in a production file of a 3D object to provide an image of a second resolution, which is higher than the first resolution of the DLP projector; and
repeating the process of depositing and radiating for a number of layers according to data in the production file.
2. The method of claim 1 , wherein each of said at least three light sources radiates a separate and independent amount of radiation provided to said layer of radiation-curable flowable build material.
3. The method of claim 1 wherein said layer of radiation-curable flowable build material is radiated in at least two phases, a first radiation scheme in a first phase and a second radiation scheme in a second phase.
4. The method of claim 3 , wherein the system comprises a production table being capable of moving in two perpendicular Cartesian axes, said axes substantially perpendicular to said light beams, and the method further comprises:
shifting said second radiation scheme with respect to said first radiation scheme along first and second perpendicular axes by shift magnitudes substantially equal to half the diameter of an image of one of said at least three light sources.
5. The method of claim 4 , wherein said radiation of said first and said second radiation schemes and the movement of said production table are controlled and synchronized by a control unit.