Abstract: Methods and systems for additive manufacturing can include a modular spreader unit including multiple spreaders that collectively span the width of a large build area. The spreaders can be arranged in offset rows so that spreaders in a second row cover gaps between spreaders in a first row. The spreaders can be secured with quick release mechanisms for rapid replacement and adjustment during service intervals.

Abstract: In one example, an apparatus for generating a three-dimensional object includes an energy source to apply energy to a layer of build material to cause a first portion of the layer to coalesce and solidify, an agent distributor to selectively deliver a cooling agent onto a second portion of the layer, and a controller to control the energy source to apply energy to the layer to cause the first portion to coalesce and solidify in a first pattern and to control the agent distributor to selectively deliver the cooling agent onto the second portion of the layer in a second pattern independent of the first pattern.

Abstract: A photocurable composition includes quantum dots, quantum dot precursor materials, a chelating agent, one or more monomers, and a photoinitiator. The quantum dots are selected to emit radiation in a first wavelength band in the visible light range in response to absorption of radiation in a second wavelength band in the UV or visible light range. The second wavelength band is different than the first wavelength band. The quantum dot precursor materials include metal atoms or metal ions corresponding to metal components present in the quantum dots. The chelating agent is configured to chelate the quantum dot precursor materials. The photoinitiator initiates polymerization of the one or more monomers in response to absorption of radiation in the second wavelength band.

Abstract: A method of fabricating an object using an additive manufacturing system includes receiving data indicative of a desired shape of the object to be fabricated by droplet ejection. The desired shape defines a profile including a top surface and one or more recesses. Data indicative of a pattern of dispensing feed material is generated to at least partially compensate for distortions of the profile caused by the additive manufacturing system, and a plurality of layers of the feed material are dispensed by droplet ejection in accordance to the pattern.

Abstract: A photocurable composition includes quantum dots, quantum dot precursor materials, a chelating agent, one or more monomers, and a photoinitiator. The quantum dots are selected to emit radiation in a first wavelength band in the visible light range in response to absorption of radiation in a second wavelength band in the UV or visible light range. The second wavelength band is different than the first wavelength band. The quantum dot precursor materials include metal atoms or metal ions corresponding to metal components present in the quantum dots. The chelating agent is configured to chelate the quantum dot precursor materials. The photoinitiator initiates polymerization of the one or more monomers in response to absorption of radiation in the second wavelength band.

Abstract: Embodiments of the present disclosure relate to advanced polishing pads with tunable chemical, material, and structural properties, and new methods of manufacturing the same. In one or more embodiments, polishing pads with improved properties may be produced by an additive manufacturing process, such as a three-dimensional (3D) printing process. Some embodiments may provide an advanced polishing pad that has discrete features and geometries, formed from at least two different materials that include functional polymers, functional oligomers, reactive diluents, addition polymer precursor compounds, catalysts, and curing agents. For example, advanced polishing pads may be formed from a plurality of polymeric layers, by the automated sequential deposition of at least one polymer precursor composition followed by at least one curing step, where each layer may represent at least one polymer composition, and/or regions of different compositions.

Abstract: Exemplary processing methods include forming a group of LED structures on a substrate layer to form a patterned LED substrate. A light absorption barrier may be deposited on the patterned LED substrate. The methods may further include exposing the patterned LED substrate to light. The light may be absorbed by surfaces of the LED structures that are in contact with the substrate layer, and the light absorption barrier. The methods may still further include separating the LED structures for the substrate layer. The bonding between the LED structures and the substrate layer may be weakened by the absorption of the light by the surfaces of the LED structures in contact with the substrate layer.

Abstract: Methods of making high-pixel-density LED structures are described. The methods may include forming a backplane substrate and a LED substrate. The backplane substrate and the LED substrate may be bonded together, and the bonded substrates may include an array of LED pixels. Each of the LED pixels may include a group of isolated subpixels. A quantum dot layer may be formed on at least one of the isolated subpixels in each of the LED pixels. The methods may further include repairing at least one defective LED pixel by forming a replacement quantum dot layer on a quantum-dot-layer-free subpixel in the defective LED pixel. The methods may also include forming a UV barrier layer on the array of LED pixels after the repairing of the at least one defective LED pixel.

Abstract: A dispensing system for an additive manufacturing includes a powder reservoir that contains powder to form an object, and an array of nozzles positioned at a base of the powder reservoir over a top surface of a platen where the object is to be formed. The powder flows from the powder reservoir through the nozzles to the top surface. A respective powder wheel in each nozzle controls a flow rate of the powder. Each wheel has multiple troughs on surface of the wheel. When a motor rotates the wheel, the troughs transport the powder through the nozzle. The rotation speed of the wheel controls the flow rate. For solid parts of the object, the wheel rotates and allows the powder to be deposited on the top surface. For empty parts of the object, the wheel remains stationary to prevent the powder from flowing to the surface.

Abstract: A dispensing system for an additive manufacturing apparatus includes a frame, a powder reservoir, an agitator and an array of dispensing units positioned below the powder reservoir. The powder reservoir has a first width along a primary axis, and includes a lower portion and an upper portion that is wider than the lower portion along a second axis perpendicular to the primary axis. The agitator is positioned in the upper portion of the powder reservoir. Each dispensing unit includes a nozzle block that has a passage therethrough that defines a nozzle and provides a respective path for the powder to flow from the powder reservoir to the nozzle, and a valve positioned in the passage in the nozzle block to controllably release powder through the nozzle.

Abstract: In one example, a lighting device for an additive manufacturing machine includes first light sources each to emit monochromatic light within a first band of wavelengths that includes a peak light absorption of a liquid coalescing agent and second light sources each to emit monochromatic light within a second band of wavelengths different from the first band of wavelengths. Each of the first light sources or each of multiple groups of the first light sources is individually addressable to emit monochromatic light independent of any other of the first light sources or of any other group of the first light sources and each of the second light sources or each of multiple groups of the second light sources is individually addressable to emit monochromatic light independent of any other of the second light sources or of any other group of the second light sources.

Abstract: A light-emitting device includes a plurality of light-emitting diodes, a first cured composition over a first subset of the light-emitting diodes, and a second cured composition over a second subset of light-emitting diodes. The first cured composition includes a first photopolymer and a blue photoluminescent material that is an organic, organometallic, or polymeric material, embedded in the first photopolymer. The second cured composition includes a second photopolymer and a nanomaterial embedded in the second photopolymer. The nanomaterial is selected to emit red or green light in response.

Abstract: Embodiments herein generally relate to polishing pads and methods of forming polishing pads. A method of forming a polishing pad includes (a) dispensing droplets of a pre-polymer composition and droplets of a sacrificial material composition onto a surface of a previously formed print layer according to a predetermined droplet dispense pattern. The method includes (b) at least partially curing the dispensed droplets of the pre-polymer composition to form a print layer. The method includes (c) sequentially repeating (a) and (b) to form a polishing layer having a plurality of pore-features formed therein. The pre-polymer composition includes a multifunctional acrylate component.

Abstract: A method for printing on a substrate includes printing a support structure by printing a liquid precursor material and curing the liquid precursor material, positioning a substrate within the support structure, printing one or more anchors on the substrate and the support structure by printing and curing the liquid precursor material to secure the substrate to the support structure, and printing one or more device structures on the substrate while anchored by printing and curing the liquid precursor material.

Abstract: Printing on a substrate includes printing a support structure by printing a liquid precursor material and curing the liquid precursor material, printing one or more alignment markers by printing the liquid precursor material outside the support structure and curing the liquid precursor material, positioning a substrate within the support structure, performing a registration of the substrate using the one or more alignment markers, and printing one or more device structures on the substrate while registered by printing and curing the liquid precursor material.

Abstract: In one example, a lighting device for an additive manufacturing machine includes an array of light sources each to emit monochromatic light within a band of wavelengths that includes a peak light absorption of a liquid coalescing agent to be dispensed on to a build material.

Abstract: A method for manufacturing micro-LED displays includes depositing a first material over a substrate having a plurality of micro-LEDs such that the plurality of micro-LEDs are covered by the first material and the first material fills gaps laterally separating the micro-LEDs, removing a portion of the first material from the gaps that laterally separate the plurality of micro-LEDs to form trenches that extend to or below light-emitting layers of the micro-LEDs, depositing a second material over the substrate such that the second material covers the first material and extends into the trenches, and removing a portion of the first and second material over the plurality of micro-LEDs to expose top surfaces of the plurality of micro-LEDs and such that isolation walls positioned in the gaps between the plurality of micro-LEDs extend vertically higher than the top surface of the first material.

Abstract: A display screen includes a backplane, an array of light-emitting diodes electrically integrated with the backplane, the array of light-emitting diodes configured to emit UV light in a first wavelength range, and a plurality of isolation walls formed on the backplane between adjacent light-emitting diodes of the array of light-emitting diodes with the isolation walls spaced apart from the light-emitting diodes and extending above the light-emitting diodes. The plurality of isolation walls include a core of a first material and a coating covering at least a portion of the core extending above the light-emitting diodes. The coating is an opaque second material having transmittance less than 1% of light in the first wavelength range.

Abstract: Exemplary processing methods of forming an LED structure on a backplane may include coupling a first transfer substrate with an LED source substrate. The LED source substrate may include a plurality of fabricated LEDs. The coupling of the first transfer substrate may be produced with a first coupling material extending between the first transfer substrate and each LED of the plurality of fabricated LEDs. The methods may include separating the LED source substrate from the LEDs. The methods may include coupling a second transfer substrate with the first transfer substrate. The coupling of the first transfer substrate may be produced with a second coupling material extending between the second transfer substrate and each LED of the plurality of fabricated LEDs. The methods may include separating the first transfer substrate from the second transfer substrate. The methods may include bonding the plurality of fabricated LEDs with a display backplane.

Abstract: An additive manufacturing system includes a platen to support an object to be fabricated, a dispenser assembly positioned above the platen, and an energy source configured to selectively fuse a layer of powder. The dispenser assembly includes a first dispenser, a second dispenser, and a drive system. The first dispenser delivers a first powder in a first linear region that extends along a first axis, and the second dispenser delivers a second powder in a second linear region that extends parallel to the first linear region and is offset from the first linear region along a second axis perpendicular to the first axis. The drive system a drive system moves the support with the first dispenser and second dispenser together along the second axis.