Systems and methods for additive manufacturing using pixel shifting
An additive manufacturing apparatus includes a support plate defining a window and a resin support configured to support an uncured layer of resin. A stage is configured to hold one or more cured layers of the resin to form a component positioned opposite a support plate. A radiant energy device is positioned on an opposite side of the resin support from the stage and is operable to project radiant energy in a grid through the window. The grid and/or pixels thereof are intelligently shifted to efficiently print one or more layers of a component.
1 . A method of additively manufacturing an object by digital light processing, comprising:
generating a layer build plan;
contacting a surface of the object with a photopolymerizable material;
flashing at least a first portion of the object with a first grid of a first plurality of pixels using a projector at a first position, the first grid comprising a first resolution;
flashing at least a second portion of the object with a second grid of a second plurality of pixels using the projector at a second position, the second grid comprising a second resolution different from the first resolution;
separating the object from the photopolymerizable material; and
iterating the method as necessary to build up the object,
wherein flashing the at least the second portion comprises tracing the second grid along a tracing path around a flashed bulk area or a perimeter of a layer, and
wherein the layer build plan indicates:
which pixels of the first plurality of pixels are to be flashed when the projector is at the first position,
a respective flash intensity of each pixel of the first plurality of pixels,
which pixels of the second plurality of pixels are to be flashed when the projector is at the second position, and
a respective flash intensity of each pixel of the second plurality of pixels.
2 . The method of claim 1 , wherein the first resolution is more coarse than the second resolution.
3 . The method of claim 1 , wherein the first resolution is finer than the second resolution.
4 . The method of claim 1 , wherein the projector is movable about a printable field.
5 . The method of claim 1 , wherein the first portion and the second portion of the object are within a same layer of the object.
6 . The method of claim 1 , wherein the first portion and the second portion of the object are within different layers of the object.
7 . The method of claim 1 , further comprising:
changing a resolution of the projector from the first resolution to the second resolution by changing a size of pixels of a grid projected by the projector.
8 . An additive manufacturing apparatus for digital light processing, comprising:
a radiant energy device having a projector;
a computing system having one or more processors, the one or more processors being configured to:
generate a layer build plan;
contact a surface of an object with a photopolymerizable material;
cause the projector to flash at least a first portion of an object with a first grid of a first plurality of pixels at a first position, the first grid comprising a first resolution;
cause the projector to flash at least a second portion of the object with a second grid of a second plurality of pixels at a second position, the second grid comprising a second resolution different from the first resolution;
separate the object from the photopolymerizable material; and
repeat contacting, flashing, and separating steps as necessary to build up the object,
wherein to cause the project to flash the at least the second portion comprises tracing the second grid along a tracing path around a flashed bulk area or a perimeter of a layer, and
wherein the layer build plan indicates:
which pixels of the first plurality of pixels are to be flashed when the projector is at the first position,
a respective flash intensity of each pixel of the first plurality of pixels, which pixels of the second plurality of pixels are to be flashed when the projector is at the second position, and
a respective flash intensity of each pixel of the second plurality of pixels.
9 . The additive manufacturing apparatus of claim 8 , wherein the first resolution is more coarse than the second resolution.
10 . The additive manufacturing apparatus of claim 8 , wherein the first resolution is finer than the second resolution.
11 . A non-transitory computer readable medium comprising computer-executable instructions, which, when executed by one or more processors of a computing system associated with an additive manufacturing apparatus, cause the one or more processors to:
generate a layer build plan;
contact a surface of an object with a photopolymerizable material;
cause a projector of a radiant energy device to flash at least a first portion of the object with a first grid of a first plurality of pixels at a first position, the first grid comprising a first resolution;
cause the projector to flash at least a second portion of the object with a second grid of a second plurality of pixels at a second position, the second grid comprising a second resolution different from the first resolution;
separate the object from the photopolymerizable material; and
repeat contacting, flashing, and separating steps as necessary to build up the object,
wherein to cause the projector to flash the at least the second portion comprises tracing the second grid along a tracing path around a flashed bulk area or a perimeter of a layer, and
wherein the layer build plan indicates:
which pixels of the first plurality of pixels are to be flashed when the projector is at the first position,
a respective flash intensity of each pixel of the first plurality of pixels,
which pixels of the second plurality of pixels are to be flashed when the projector is at the second position, and
a respective flash intensity of each pixel of the second plurality of pixels.
12 . The method of claim 1 , wherein optimization rules dictate how the first and second grids are moved around and flashed.
13 . The method of claim 12 , wherein the optimization rules comprise rules associated with minimizing a shifting distance from one grid position to another grid position.
14 . The method of claim 12 , wherein the optimization rules comprise rules associated with minimizing a number of shifts needed for printing the layer.
15 . The method of claim 12 , wherein the optimization rules comprise rules associated with avoiding flash overlap.
16 . The method of claim 12 , wherein the optimization rules comprise rules associated with reducing flash intensity at overlap regions between pixels.
17 . The method of claim 1 , wherein a subset of pixels are moved at a first speed along a first portion of a tracing path and at a second speed along a second portion of the tracing path.
18 . The method of claim 17 , wherein the first speed is greater than the second speed.
19 . The method of claim 17 , wherein the subset of pixels are flashed continuously.
20 . The method of claim 17 , wherein the subset of pixels are flashed periodically.