Multiple image projection system for additive manufacturing

1. An additive manufacturing system, comprising:

an image projection system comprising a plurality of image projectors that project a composite image onto a build area within a resin pool, wherein each of the image projectors projects a sub-image onto a portion of the build area, wherein the composite image comprises a plurality of sub-images arranged in an array, and wherein two or more adjacent sub-images in the array overlap at two or more sub-image edges;

a display subsystem, wherein the display subsystem controls the image projection system and each of the image projectors to adjust properties and alignment of a position of each sub-image in the array; and

a stack of filters configured to adjust the properties of each sub-image in the array, the stack of filters comprising:

an irradiance mask configured to normalize irradiance;

a gamma adjustment mask configured to adjust sub-image energy by mapping a plurality of pixel intensity levels to an addressable range of reactivity for curing resin of the resin pool, thereby reducing aliasing artifacts of curved or smooth surfaces;

a warp correction filter configured to provide geometric correction; and

an edge blending bar at one or more sub-image edges.

2. The additive manufacturing system of claim 1 , wherein the plurality of pixel intensity levels comprises levels from 0 to 255.

3. The additive manufacturing system of claim 1 , wherein the gamma adjustment mask further comprises a transfer function that maps an operating energy range of a printed layer to a control system operating range, wherein the control system operating range is a quantized set of values.

4. The additive manufacturing system of claim 1 , wherein the gamma adjustment mask comprises a logarithmic relationship between a cure depth of the resin and energy per unit area in the build area.

5. The additive manufacturing system of claim 1 , further comprising the resin pool, wherein the resin of the resin pool is selected from a group consisting of acrylates, epoxies, methacrylates, urethanes, silicone, vinyls, and combinations thereof.

6. The additive manufacturing system of claim 1 , wherein adjacent sub-areas overlap by a percentage of their areas, wherein the percentage is from 1% to 5%.

7. The additive manufacturing system of claim 1 , wherein adjacent sub-areas overlap by a percentage of their areas, wherein the percentage is from 50% to 100% to increase a local power within the composite image.

8. The additive manufacturing system of claim 1 , wherein the warp correction filter corrects skew in projected images that are caused by variation in alignment within the build area.

9. The additive manufacturing system of claim 1 , wherein the warp correction filter corrects skew in projected images that are caused by variation in projector optics.

10. The additive manufacturing system of claim 1 , wherein the edge blending bar comprises a blending distance and a function selected from a group consisting of linear, sigmoid and geometric.

11. A method comprising:

a. providing an additive manufacturing system, comprising:

an image projection system comprising a plurality of image projectors; and

an image display subsystem;

b. projecting a composite image onto a build area within a resin pool using the image projection system, wherein:

the image projection system is controlled by the image display subsystem;

the composite image comprises a plurality of sub-images arranged in an array;

two or more adjacent sub-images in the array overlap at two or more sub-image edges; and

each sub-image is projected onto a portion of the build area using one of the plurality of image projectors; and

c. adjusting properties and aligning a position of each sub-image in the array using a set of filters comprising:

an irradiance mask that normalizes irradiance;

a gamma adjustment mask that adjusts sub-image energy by mapping a plurality of pixel intensity levels to an addressable range of reactivity for curing the resin of the resin pool, thereby reducing aliasing artifacts of curved or smooth surfaces;

a warp correction filter that provides geometric correction; and

an edge blending bar at one or more sub-image edges.

12. The method of claim 11 , wherein the plurality of pixel intensity levels comprises levels from 0 to 255.

13. The method of claim 11 , wherein the gamma adjustment mask further comprises a transfer function that maps an operating energy range of a printed layer to a control system operating range, wherein the control system operating range is a quantized set of values.

14. The method of claim 11 , wherein the gamma adjustment mask comprises a logarithmic relationship between a cure depth of the resin and energy per unit area in the build area.

15. The method of claim 11 , wherein the resin is selected from a group consisting of acrylates, epoxies, methacrylates, urethanes, silicone, vinyls, and combinations thereof.

16. The method of claim 11 , wherein adjacent sub-areas overlap by a percentage of their areas, wherein the percentage is from 1% to 5%.

17. The method of claim 11 , wherein adjacent sub-areas overlap by a percentage of their areas, wherein the percentage is from 50% to 100% to increase a local power within the composite image.

18. The method of claim 11 , wherein the warp correction filter corrects skew in projected images that are caused by variation in alignment within the build area.

19. The method of claim 11 , wherein the warp correction filter corrects skew in projected images that are caused by variation in projector optics.

20. The method of claim 11 , wherein the edge blending bar comprises a blending distance and a function selected from a group consisting of linear, sigmoid and geometric.