US-12623404-B2 - Distributed flux array

Abstract

An apparatus includes at least one laser source and a print bed. A light valve array having at least three optically addressable light valves is positioned to direct differing images at the print bed. Optics to direct multiple beams derived from the at least one laser source can be positioned to direct light toward and from the optically addressable light valves.

Inventors

• Susanne Kras
• James A. DEMUTH
• Andrew J. Bayramian
• Francis L. Leard
• Drew W. Kissinger
• Cote LeBlanc

Assignees

• Seurat Technologies, Inc.

Dates

Publication Date

20260512

Application Date

20231130

Claims (16)

1. 1 . An additive manufacturing system, comprising: at least one laser source providing an illumination beam; a print bed; a light valve array having at least three optically addressable light valves (OALVs); first optics configured to split the illumination beam into multiple unpatterned beams and to direct the multiple unpatterned beams onto the at least three OALVs respectively, wherein each OALV patterns a respective image upon a respective unpatterned beam to be a patterned beam; and second optics configured to steer the patterned beams of the at least three OALVs at the print bed for printing an object, wherein the respective images patterned into the beams from the OALVs are arranged in a checkerboard pattern of tiles on the print bed, with each image being one tile in the checkerboard pattern; wherein the checkerboard pattern is shifted multiple times in different directions to result in a distributed pattern of tiles being printed on the print bed.
2. 2 . The additive manufacturing system of claim 1 , wherein the images directed at the print bed are meshed or matched together at their edges to form a single image.
3. 3 . The additive manufacturing system of claim 1 , wherein the images directed at the print bed are overlapped together at their edges to form a single image.
4. 4 . The additive manufacturing system of claim 1 , wherein the at least one laser source further comprises at least two laser sources of different wavelength.
5. 5 . An additive manufacturing method, comprising: providing a illumination beam from at least one laser source; deriving at least three beams from the laser source; using first optics to split the illumination beam into multiple unpatterned beams and to direct the multiple unpatterned beams onto at least three optically addressable light valves (OALVs) respectively, wherein each OALV patterns a respective image upon a respective unpatterned beam to be a patterned beam; and using second optics to steer the patterned beams from the at least three OALVs at a print bed for printing an object, wherein the respective images patterned into the beams from the OALVs are arranged in a checkerboard pattern of tiles on the print bed, with each image being one tile in the checkerboard pattern, wherein the checkerboard pattern is shifted multiple times in different directions to result in a distributed pattern of tiles being printed on the print bed.
6. 6 . The additive manufacturing method of claim 5 , wherein the images directed at the print bed are meshed or matched together at their edges to form a single image.
7. 7 . The additive manufacturing method of claim 5 , wherein the images directed at the print bed are overlapped together at their edges to form a single image.
8. 8 . The additive manufacturing method of claim 5 , wherein the at least one laser source further comprises at least two laser sources of different wavelength.
9. 9 . An additive manufacturing system, comprising: multiple laser sources providing an illumination beam; a print bed; a light valve array having multiple optically addressable light valves (OALVs); and first optics configured to split the illumination beam into multiple unpatterned beam and to direct the multiple unpatterned beams onto the multiple OALVs, wherein each OALV patterns a respective two-dimensional image upon a respective unpatterned beam; and second optics configured to steer the patterned beams from the at least three OALVs at the print bed for printing an object, wherein the respective images patterned into the beams from the OALVs are arranged in a checkerboard pattern of tiles on the print bed, with each image being one tile in the checkerboard pattern, wherein the checkerboard pattern is shifted multiple times in different directions to result in a distributed pattern of tiles being printed on the print bed.
10. 10 . The additive manufacturing system of claim 9 , wherein the first optics are configured to combine the multiple laser beams into the illumination beam.
11. 11 . The additive manufacturing system of claim 9 , further comprising secondary optics configured to modify the two-dimensional images after interaction with the multiple optically addressable light valves.
12. 12 . The additive manufacturing system of claim 9 , wherein at least some of the two-dimensional images from the light valve array are superimposed at the print bed.
13. 13 . An additive manufacturing method, comprising: using multiple laser sources to provide an illumination beam; using first optics to split the illumination beam into multiple unpatterned beam and to direct the multiple unpatterned beams onto multiple optically addressable light valves (OALVs) respectively, wherein each OALV patterns a respective two-dimensional image upon a respective unpatterned beam; and using second optics to steer the patterned beams from the multiple OALVs at a print bed for printing an object, wherein the respective images patterned into the beams from the multiple OALVs are arranged in a checkerboard pattern of tiles on the print bed, with each image being one tile in the checkerboard pattern, wherein the checkerboard pattern is shifted multiple times in different directions to result in a distributed pattern of tiles being printed on the print bed.
14. 14 . The additive manufacturing method of claim 13 , wherein the first optics are configured to combine the multiple laser beams into the illumination beam.
15. 15 . The additive manufacturing method of claim 13 , further comprising modifying the two-dimensional images by secondary optics after interaction with the multiple optically addressable light valves.
16. 16 . The additive manufacturing method of claim 13 , wherein at least some of the two-dimensional images from the light valve array are superimposed at the print bed.

Description

RELATED APPLICATION This application is a continuation of U.S. patent application Ser. No. 17/506,425, filed Oct. 20, 2021, which claims the priority benefit of U.S. Patent Application No. 63/107,100, filed on Oct. 29, 2020, both of which are incorporated by reference in their entirety. TECHNICAL FIELD The present disclosure generally relates to increasing energy in an additive manufacturing system. This can include splitting the incoming illumination beams between two or more optically addressable light valves (OALV), each imprinting the same image on the beam. The images can be superimposed or overlaid to form a single image, or alternatively used to form a distributed image. BACKGROUND In the field of metal additive manufacturing (AM), the incoming optical field can be a high fluence laser source. Unfortunately, such industrial applications require that optically addressable light valves withstand high fluence laser sources for a prolonged period of time so as to allow the production of multiple build cycles within a typical shot count in the tens of millions to billions. The energy required to print materials in a reasonable time can exceed 8 J/cm2 at the print plane. While various methods can be used to reduce the fluence at the optically addressable light valves, commercially practicable industrial processing requires that the energy density at the optically addressable light valves to be not less than 2 J/cm2. Existing optically addressable light valves fail at far below this fluence, making techniques for reducing optical light valve damage necessary. BRIEF DESCRIPTION OF THE DRAWINGS Non-limiting and non-exhaustive embodiments of the present disclosure are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various figures unless otherwise specified. FIG. 1 illustrates a system to combine, split and image the incoming illumination beams onto each element of the transmissive light valve array, then image and shift the beams exiting from each light valve to form the desired configuration of image tiles at the build plane; FIG. 2 illustrates a system to combine, split and image the incoming illumination beams onto each element of the reflective light valve array, then image and shift the beams exiting from each light valve to form the desired configuration of image tiles at the build plane; FIG. 3 illustrates a system to split and image the incoming illumination beam onto each element of the light valve array (which can be transmissive or reflective), then image and shift the beams exiting from each light valve to form the desired configuration of image tiles at the build plane; FIG. 4 illustrates a system to combine incoming illumination beams, split and image the combined incoming illumination beam onto each element of the light valve array (which can be transmissive or reflective), then image and shift the beams exiting from each light valve to form the desired configuration of image tiles at the build plane; FIG. 5 illustrates a system to split each of two incoming illumination beams into an M×N array of beams, overlay the incoming illumination beam arrays using one or more optical combiners, and image each combined beam onto an element of the light valve array (which can be transmissive or reflective). The output from each light valve is imaged and shifted to form the desired configuration of image tiles at the build plane; FIG. 6 illustrates a system to illuminate two independently controlled transmissive light valves with two different sources, then superimpose the images and relay them to the build plane; FIG. 7 illustrates a system to illuminate two independently controlled reflective light valves with two different sources, then superimpose the images and relay them to the build plane; FIG. 8 illustrates a system to split an incoming beam into multiple beams using arrays of reflective or refractive optical elements, then image the beams onto multiple light valves; FIG. 9 illustrates a system to split an incoming beam into multiple beams using lens arrays, then image the beams onto multiple light valves; FIG. 10 illustrates a system to split an incoming beam into multiple beams using arrays of prisms, then image the beams onto multiple light valves; FIG. 11 illustrates a system to split an incoming beam into multiple beams using arrays of mirrors, then image the beams onto multiple light valves; FIG. 12 illustrates a system to split an incoming beam into multiple beams using arrays of diffractive optical elements, then image the beams onto multiple light valves; FIG. 13 illustrates a system to use arrays of refractive or reflective optics to shift and image the output from an M×N light valve array to form a distributed pattern of image tiles at the build plane; FIG. 14 illustrates a system to use arrays of lens segments to shift and image the output from an M×N light valve array to form a distributed pattern of image tiles at t