A display may include illumination optics, a ferroelectric liquid crystal on silicon (fLCOS) panel, and a waveguide. A twisted nematic cell may be optically interposed between the fLCOS panel and the waveguide. A birefringent crystal may be optically interposed between the cell and the waveguide. The cell may have a first state in which the cell transmits the image light with a first polarization and a second state in which the cell transmits the image light with a second polarization. The crystal may transmit the image light within spatially offset beams based on polarization. In another arrangement, a quarter waveplate may be optically interposed between the cell and the waveguide and a geometric phase grating may be optically interposed between the quarter waveplate and the waveguide. Control circuitry may toggle the cell between the first and second states to maximize the effective resolution of images at an eye box.

A method of additive manufacture is disclosed. The method may include creating, by a 3D printer contained within an enclosure, a part having a weight greater than or equal to 2,000 kilograms. A gas management system may maintain gaseous oxygen within the enclosure atmospheric level. In some embodiments, a wheeled vehicle may transport the part from inside the enclosure, through an airlock, as the airlock operates to buffer between a gaseous environment within the enclosure and a gaseous environment outside the enclosure, and to a location exterior to both the enclosure and the airlock.

A method of additive manufacture is disclosed. The method may include creating, by a 3D printer contained within an enclosure, a part having a weight greater than or equal to 2,000 kilograms. A gas management system may maintain gaseous oxygen within the enclosure atmospheric level. In some embodiments, a wheeled vehicle may transport the part from inside the enclosure, through an airlock, as the airlock operates to buffer between a gaseous environment within the enclosure and a gaseous environment outside the enclosure, and to a location exterior to both the enclosure and the airlock.

A method of additive manufacture suitable for large and high resolution structures is disclosed. The method may include sequentially advancing each portion of a continuous part in the longitudinal direction from a first zone to a second zone. In the first zone, selected granules of a granular material may be amalgamated. In the second zone, unamalgamated granules of the granular material may be removed. The method may further include advancing a first portion of the continuous part from the second zone to a third zone while (1) a last portion of the continuous part is formed within the first zone and (2) the first portion is maintained in the same position in the lateral and transverse directions that the first portion occupied within the first zone and the second zone.

A method of additive manufacture suitable for large and high resolution structures is disclosed. The method may include sequentially advancing each portion of a continuous part in the longitudinal direction from a first zone to a second zone. In the first zone, selected granules of a granular material may be amalgamated. In the second zone, unamalgamated granules of the granular material may be removed. The method may further include advancing a first portion of the continuous part from the second zone to a third zone while (1) a last portion of the continuous part is formed within the first zone and (2) the first portion is maintained in the same position in the lateral and transverse directions that the first portion occupied within the first zone and the second zone.

An apparatus and a method for powder bed fusion additive manufacturing involve a multiple-chamber design achieving a high efficiency and throughput. The multiple-chamber design features concurrent printing of one or more print jobs inside one or more build chambers, side removals of printed objects from build chambers allowing quick exchanges of powdered materials, and capabilities of elevated process temperature controls of build chambers and post processing heat treatments of printed objects. The multiple-chamber design also includes a height-adjustable optical assembly in combination with a fixed build platform method suitable for large and heavy printed objects.

An apparatus and a method for powder bed fusion additive manufacturing involve a multiple-chamber design achieving a high efficiency and throughput. The multiple-chamber design features concurrent printing of one or more print jobs inside one or more build chambers, side removals of printed objects from build chambers allowing quick exchanges of powdered materials, and capabilities of elevated process temperature controls of build chambers and post processing heat treatments of printed objects. The multiple-chamber design also includes a height-adjustable optical assembly in combination with a fixed build platform method suitable for large and heavy printed objects.

A method of additive manufacture is disclosed. The method may include restricting, by an enclosure, an exchange of gaseous matter between an interior of the enclosure and an exterior of the enclosure. The method may further include running multiple machines within the enclosure. Each of the machines may execute its own process of additive manufacture. While the machines are running, a gas management system may maintain gaseous oxygen within the enclosure at or below a limiting oxygen concentration for the interior.

A method of additive manufacture is disclosed. The method may include restricting, by an enclosure, an exchange of gaseous matter between an interior of the enclosure and an exterior of the enclosure. The method may further include running multiple machines within the enclosure. Each of the machines may execute its own process of additive manufacture. While the machines are running, a gas management system may maintain gaseous oxygen within the enclosure at or below a limiting oxygen concentration for the interior.

A method of manufacturing a segmented electro-optic display includes providing an electro-optic display stack including a first substrate layer, a first layer of light-transmissive electrically-conductive material, a layer of electro-optic material, a lamination adhesive, a second layer of light-transmissive electrically-conductive material, and a second substrate layer. The method also includes forming electrically-isolated conductive segments on the second layer of electrically-conductive material using a laser etching process that includes irradiating the second substrate and second electrically-conductive layers at multiple locations with a laser emitting light within a first range of wavelengths. The second substrate layer is transmissive of light within the first range of wavelengths, and the light-transmissive electrically-conductive material is substantially absorptive of light within the first range of wavelengths. At each of the multiple locations, the second substrate layer substantially transmits the light emitted from the laser and the light-transmissive electrically-conductive material substantially absorbs the light and is removed.