Large-area arrayed light bulbs

Abstract

The additive manufacturing system includes at least two photoconductor plates attached to a substrate, each of which can include a separate linear electrical layer and a transparent conductive oxide layer.

Description

[Technical Field]

[0001] Related applications This disclosure is part of a non-provisional patent application claiming priority to U.S. Patent Application No. 63 / 107,260, filed on 29 October 2020, and is incorporated in its entirety by reference.

[0002] This disclosure generally relates to large-area arrayed light bulb systems. More specifically, it describes the use of arrayed photoconductors fixed to a substrate. [Background technology]

[0003] High-power laser systems with lights capable of high fluence and long-term operation are useful for additive manufacturing and other applications that can benefit from the use of patterned high-energy lasers. Unfortunately, the light bulbs used in many conventional high-energy / power systems are limited in size by how large their photoconductors can be grown. For example, high-quality bismuth B silicate 12 SiO 20 (BSO) crystal plates are typically limited to 30mm x 30mm in size because growing larger crystal boules to obtain larger plates reduces yield due to impurities and defects. As a result, light bulbs obtained from these plates have a limited clear aperture of approximately 30mm x 30mm. This limitation of the clear aperture affects the manufacturing speed of metal additive manufacturing, as the energy fluence must be kept below the damage threshold in a specific area of ​​the clear aperture. What is needed is a technique and structure that can provide a large clear aperture by fabricating large-area light bulbs while continuing to use cost-effective current crystal growth methods.

[0004] Non-limiting and non-exclusive embodiments of this disclosure are described with reference to the following figures, where similar reference numerals refer to similar parts throughout the various figures unless otherwise specified. [Brief explanation of the drawing]

[0005] [Figure 1A(i)] This shows a photoconductor complex (PC) for improved light bulb (LV) operation. [Figure 1A(ii)] This shows a photoconductor complex (PC) for improved light bulb (LV) operation. [Figure 1A(iii)] This shows a photoconductor complex (PC) for improved light bulb (LV) operation. [Figure 1B(i)] This shows an embodiment of a photoconductor composite for large-area LV. [Figure 1B(ii)] This shows an embodiment of a photoconductor composite for large-area LV. [Figure 1C] This shows the segmentation process for parallel LV manufacturing. [Figure 1D] This demonstrates the manufacturing of arrayed LVs that are independent of PC thickness. [Figure 1E] This shows the arraying of photoconductor blocks to enable the creation of large-area photoconductor plates. [Figure 2] This shows a block diagram of a high-fluence light bulb-based additive manufacturing system that supports beam dumping, large-area arrayed light bulbs, and heat engines. [Figure 3] This demonstrates a high-fluence, large-area arrayed light bulb-based laminated manufacturing system. [Figure 4] This shows another embodiment of a high-fluence, large-area arrayed light bulb-based laminated manufacturing system. [Figure 5] This exhibits another embodiment of a high-fluence, large-area arrayed light bulb-based laminated fabrication that incorporates a switchyard technique for waste energy recovery and further use. [Modes for carrying out the invention]

[0006] In the following description, reference is made to the accompanying drawings which illustrate, in an illustrative way, specific exemplary embodiments that form part of and can implement the disclosure. These embodiments are described in sufficient detail so that those skilled in the art can practice the concepts disclosed herein, and modifications can be made to the various disclosed embodiments without departing from the scope of the disclosure, and it should be understood that other embodiments can be utilized. Thus, the following detailed description is not taken in a limiting sense.

[0007] In the following disclosure, the light valve includes a photoconductor composite assembly composed of a photoconductor plate coupled to a rigid and flat support substrate.

[0008] The photoconductor plate is typically BSO, but can also be composed of other photoconductors.

[0009] The support substrate material (SSM) is typically C-cut sapphire or crystalline quartz and can have sufficient rigidity to be coated.

[0010] The bonding material can be sodium silicate.

[0011] The SSM can be coated with many anti-reflection (AR) and transparent conductive oxide (TCO) coatings, which are usually present on the PC and are prone to deforming the PC. The absence of deformation during the coating process facilitates the assembly of the LV and optimizes the performance of the LV.

[0012] An electrical connection can be achieved by fabricating a support substrate larger than the PC and extending the TCO layer beyond the entire aperture of the PC, thereby being unaffected by the high fluence laser (HFL), optimizing the available aperture of the PC, and maintaining a high LV laser damage threshold.

[0013] Due to the flexibility of the PC, the PC can be deformed during the composite process to take on the good surface shape of the SSM.

[0014] In some embodiments, the compounding process allows the PC to be polished without deformation.

[0015] In some embodiments, the compounding process allows for coating the outer surface of the PC without deformation.

[0016] In some embodiments, the compounding process allows the PC to be repeatedly repaired.

[0017] In some embodiments, the composite process can be applied to an array of PCs on a larger support substrate to enable the realization of large-area LVs.

[0018] In some embodiments, the array is post-treated for flatness and coating.

[0019] In some embodiments, a composite PC array process can be used to enable parallel PC composite manufacturing, where PC composite assemblies are pieced together from large-area PC composites.

[0020] In some embodiments, a composite PC array process can be used to apply wafer-scale manufacturing to LV construction, and the entire LV construction process is performed in an automated format.

[0021] In one embodiment, to achieve uniform flatness, the PCs are not polished together afterward. In this case, individual secondary substrates are picked and placed, and individual LV segments are constructed on a large-area PC composite.

[0022] In some embodiments, the process in (a) allows for the application of ceramic electrical connections, or in combination with flexible circuits, thereby reducing assembly and LV costs.

[0023] In some embodiments, flexible LV structures are made possible by the use of flexible electrical backplanes used in astronomical or laser weapon systems.

[0024] In some embodiments, the flexible LV structure replaces conventional optical systems that require compensation (such as changes in optical response, like zoom lenses or pattern reformatting).

[0025] In some embodiments, a composite array method can be applied to construct a large-area PC from individual high-yield PC blocks.

[0026] In some embodiments, a large-area plate to be fragmented can be formed by an array of smaller blocks of composite material before the final surface finishing and plate fragmentation.

[0027] Large-area light bulbs (LVs) can be manufactured by arranging smaller, less expensive, and higher-yield photoconductor (PC) plates as an array on a high-damage-threshold support substrate (SSM) material such as sapphire. The PC plates can be fixed using atomic or diffusion bonding, etchant-reinforced welding, glass frit epoxy bonding ("frit" is intended to include all forms of glass powder-based epoxy), molten glass bonding (also known as glass adhesive), and even certain polymer-based epoxy bonding.

[0028] Lateral arraying can be performed by arranging PC on sapphire using glass adhesive. This arraying is sometimes called sistering or compounding of PC on a SSM. Arraying can also be performed before mounting to the SSM by sizing PC bars obtained from a boule of PC to ensure a high process yield. The bars are mounted on their sides using one of the fixing methods and then sliced ​​into plates as if obtained from a large boule. Sistering / compounding to the SSM can then be performed as if it were a single homogeneous plate.

[0029] The direct advantage is that large-area LVs can be manufactured without the need to grow boules to support plates of that size. The additional benefit of contacting the PC plates to the SSM by the same fixing method allows the PC plates to be shaped to conform to the flatness of the SSM. This can be controlled with greater precision than the precision of PC (which is difficult to grow). The lateral arrayed PC arrangement on the SSM can then be machined into improved surface geometries that may not be possible with a single, non-flexible PC plate element. Such machining can include corrections for PC flatness, wedge, and power aberrations. The ability to make LVs of any size, while also controlling and correcting optical aberrations inherent in all LVs, is a significant additional benefit of arraying PCs in this manner.

[0030] Advantageously, PC flatness allows the linear electrical layer (LEO, typically liquid crystal) to be well controlled. The uniformity of the LEO layer thickness determines the contrast uniformity (in amplitude or phase) across the LV's clear aperture, resulting in maximum resolution and contrast control on the printed surface.

[0031] Another embodiment provides a PC composite on top of an SSM, where individual LV cells for each PC are arranged side-by-side using individual secondary substrates. These secondary substrates can provide conductivity from the inside to the outside of the cells without compromising PC density / arrangement, using plated through-holes or round-edge plating to enable upper-side conductivity. Since epoxy and conductive wires need to be protected from high-fluence systems, two ceramic "window frame" arrays can be placed on either side of the LV, with the input side structured to be non-conductive and the output side including protected conductive wires and flexible electrical connections to ensure conductivity for individual LV circuits.

[0032] An additional benefit of compounding individual PC plates into a larger SSM is that it enables parallel photoconductor manufacturing by fixing the components to the wafer, packaging them, and then dicing the system from the wafer. This method allows the automated process to be used for LV construction, improving yield and reducing cycle and test times.

[0033] Figure 1A(i-iii) shows a photoconductor composite (PC) 100A for improved light bulb (LV) operation. The composite (110A) begins with an SSM (120A) containing anti-reflective and transparent conductive oxide coatings on the inside (130A, AR, and TCO, respectively). The SSM can be made flat over 95% of its surface (at 632 nm, <λ / 10) and has much higher rigidity than the paired PC. This rigidity can be achieved by using a material that is inherently strong (i.e., Mohs hardness > 9), or by using a thicker substrate, or a combination of both. The SSM should have negligible absorption over the wavelength band of the expected operation. An exemplary transmission band is 990 nm to 1070 nm, which fits current diode and pulsed laser sources for multilayer fabrication. The SSM should also preferably have its thermal expansion matched with the selected PC. This is important in many thermal processes required during the manufacturing process, including the fixing process itself, the polishing process, the coating process, the curing of the alignment and LEO layers during LV manufacturing, and the high power requirements of the LV in operation. Excellent candidate materials for the support substrate include C-cut sapphire, 7979 quartz glass, silicon carbide, silicon nitride, diamond, calcium fluoride, crystalline quartz, ZnSe, or similar types of materials. The photoconductor (PC) is attached at 130A between 140A and 130A (arrow 150A), and this attachment can include atomic or diffusion bonding, etchant-reinforced welding, glass frit epoxy bonding ("frit" is intended to include all forms of glass powder-based epoxy), molten glass bonding (also called glass adhesive), polymer-based epoxy bonding, or similar fixing methods that can withstand the required laser fluence while producing a bond with negligible absorption and high strength. Figure 1A(ii) shows the resulting structure (160A) that forms part of the PC composite assembly.As can be seen in Fig. 1A(iii), this assembly (160A) can then be used to construct an LV assembly (170A) that includes 160A, along with a linear electro-optic and spacing assembly (190A) and a secondary substrate (200A) that includes a TCO and an AR coating layer, in a standard LV construction process (220A) for forming the assembled composite LV (230A).

[0034] There are several benefits obtained by using composite PCs. In most cases, a number of materials can be listed as PC materials, for example, bismuth silicate (BSO, or Bi 12 SiO 20 、Bi6SiO 10 、Bi3SiO5, and similar compounds), bismuth germanate (BGO, or Bi 12 GeO 20 、Bi6GeO 10 、Bi3GeO5, and similar compounds), cadmium selenide (CdSe), and crystals of the same type. The photoconductor layer can also be composed of chalcogenide glasses such as Ge2Sb2Te5 (GST), Sc 0.2 Sb2Te3, GeTe, Ag4In3Sb 67 Te 26 、Ge 15 Sb 85 、or Sb. Furthermore, it can also be composed of polycrystalline materials such as CdTe, AZO, ZnSe, ZnS, or amorphous Si.

[0035] A common attribute of these materials is that they are fragile, soft, and do not have the rigidity required to ensure a flat reference surface on which the LEO layer can be constructed. By crystallizing or compositing a typical PC (BSO) onto a much more rigid substrate, the lack of rigidity of the typical PC becomes an advantage as the bonding to the more rigid substrate causes the PC to "follow" the surface shape of the SSM. Furthermore, a support substrate can be used to enable the exposed PC surface to be polished flat without the risk of the component deforming due to internal stress after manufacturing.

[0036] Typically, self-supporting PCs in LV require several types of AR and TCO coatings, all of which add strain to the PC surface, resulting in PC deformation. After applying these high-strain coatings, it is commonly observed that the uncoated, flat PC is dramatically deformed, or "potato chipped." The flat PC is necessary to ensure that the LEO layer it is paired with has a uniform thickness, as this LV attribute guarantees the best contrast uniformity, best dynamic range, and fastest frame rate in LV. In the case of this composite, almost all high-strain coatings can be applied to the support substrate before the PC is composited to the support substrate, eliminating the possibility of PC distortion and providing the additional benefit of having a highly rigid PC to which the inner coating can be applied without the risk of PC deformation.

[0037] A further advantage of having the support substrate, rather than being on the PC, have the TCO layer is that the support substrate can be larger than the PC, and therefore any connection point can be located well outside the entire aperture of the PC. This allows for the use of even larger available apertures for beam patterning. In existing LV assemblies, care must be taken to ensure that vulnerable electrical connections and adhesive bonds are protected from the flux of the HFL, which can induce laser damage that significantly reduces the available aperture of the device.

[0038] A further advantage of the composite method is the possibility of reusing the PC if it is damaged during LV operation. Even if there is moderate laser damage to the PC, it can be repaired to a nearly intact level by a subsequent process of thinning the affected area, but this process carries all the same risks as the initial manufacturing process has with an intact PC plate. The composite method eliminates this risk by allowing repair of the area supported by the SSM, thereby making the damaged PC usable again. If the initial PC size starts at a thickness of 1.1 mm, this repair process allows for more than 10 repair cycles before the PC is consumed to the point of unusable.

[0039] Figures 1B(i-ii) show embodiments of photoconductor composite (PC) 100B for large-area LV. The array of composite PCs includes a support substrate (110B) of appropriate size that provides the area necessary to accommodate multiple PCs to be composited. In the example shown with respect to Figure 1B(i), a 2×2 array or four PC plates (an example of one such plate is 130B) are mounted on 110B. The substrate 110B can be coated (120B) before pick-and-place of the PCs, and the composite process can be carried out on each / all PC plates. The specifications for any one PC plate may be the same (typically 30×30mm×1.1mm thick), but due to variations in their polishing and processing, all plates usually exceed their tolerance limits. The limits were selected to obtain a higher yield (>75% before coating). The pick-and-place process combined with the composite process is shown with respect to Figure 1B(ii), and a side view of the 2×2 example shown in 140B is obtained. An example of PC thickness variation is shown in the exaggerated side view. The benefit of the composite process and structure is that the support substrate can be used as a backing plate, allowing the ensemble of PCs placed on it to be machined as a single piece during the polishing process (150B). In the polishing process (150B), the height variation across the group of PCs in the array is removed, and the entire group has a coplanar surface (shown in 155B) and forms a coplanar composite array of PCs (160B). The generation of the LV begins in 160B (shown as 170B) and is combined with the LEO assembly (180B, consisting of edge epoxy, spacers, and typically containing liquid crystal) and mounted by construction process 210B to a second support substrate (200B) containing TCO and AR layers (190B), which construction process 210B makes this a large-area composite LV (220B).

[0040] The advantage of this method is that the light bulb can be made of any size here, and it relies solely on the ability to form high-yield PC plates, rather than on the growth capacity of the PC. All the advantages mentioned above for a single composite LV can also be used for the array version.

[0041] Figure 1C shows the dicing for parallel LV manufacturing 100C. The arrayed PC composite 110C allows for large-area pick-and-place of many PCs onto a support substrate, and enables dicing of the array after all PCs have been composited onto the support substrate. An example of this is shown in 120C, which represents a large array of composited PCs on a large support substrate, and three possible regions of interest, namely a single composited PC (120C), a 2x2 array (140C), and a 3x3 array (150C), are diced and diced from this large carrier. These arrays are diced from 110C and assembled individually into LVs of different sizes, with 160C, 170C, and 180C associated with 130C, 140C, and 150C, respectively. The advantage of this method is that the parallel manufacturing capability can reduce the overall cost of manufacturing composited PCs, and therefore LVs. Performing the array polishing discussed in Figure 1B(ii) on the entire array before dicing can provide planar similarity across the entire array, as well as a reduction in panel-to-panel variability and the resulting dicing.

[0042] Figure 1D illustrates the fabrication of an arrayed LV100D that is independent of the PC thickness. PC plates are picked and placed on a large-area support substrate to form an array of composite PCs (110D). Electrical connections to the TCO layer are shown as extensions of the TCO into areas without composite PCs, shown as 120D. A side view of the resulting LV laminate (130D) shows that this embodiment includes a non-conductive ceramic protective screen (140D is a side view, and 200D is a plan view), an array of non-planar composite PCs, individual deposited LEO assemblies on the inner surface of individual PCs (160D), an AR / TCO layer on each discrete array of the secondary support substrate (170D), and a flexible conductive connection mounting layer (180D) attached to the secondary ceramic protective screen (190D; 200 is its plan view). Each PC plate contains a separate LEO and support substrate, so the epoxy defining the spacing and conductive paths needs to be protected from the high-fluence laser (HFL), and therefore protective screens (140D and 190D) need to sandwich the LV assembly. A second substrate containing the TCO on the inside (next to 160D) can have conductive paths that allow electrical connection to the outside of the LEO layer. This can be done by adjusting the TCO layer on the secondary substrate (220D) using one of several possible methods, two of which are shown. The inner surface (the surface in contact with 160D) is coated with an AR / TCO layer 230D. One or more corners of 220D (one is shown here) are inner-to-outer connection paths (240D) that allow electrical connection. Edge wrap deposition (250D) can be used, where the bond line trace extends from the surface to the edge, up the side of the part, to the electrical pad located on the outside of the part. On the other hand, another method is plated through-hole (260D), where a pre-drilled hole 220D is plated to allow for an upper electrical connection.

[0043] The advantage of this embodiment is that it eliminates the need for the polishing step shown in Figure 1B(ii) to flatten the PC surface, which consequently carries the risk of destroying, cracking, or damaging the composite PC components during the polishing process. Furthermore, this method allows for the parallelization of entire LV assemblies using automated manufacturing equipment, dramatically reducing the manufacturing cost of forming large-area LVs. The upper conductive contacts are gathered and led to edge contacts in the 180D layer, protected from HFL by the 140D and 190D layers. In addition, the 180D layer is often a flexible circuit including pin grid arrays or other flexible electrical connections, reducing construction complexity and lowering system costs. The advantage of flexible electrical connections is that the support substrates can be pieced together after the LV array is assembled, allowing the arrayed LVs to be used in applications requiring the curvature of the array set of LVs, one example being adaptive optics in astronomical telescopes or laser-grade weapon systems, replacing the primary adaptive optics system. A secondary benefit is that because LVs can have phase and / or amplitude response capabilities, large-area LV array assemblies can replace optical elements / systems that require compensation, such as zoom lenses or beam reformatting.

[0044] Figure 1E shows the arraying of photoconductor blocks to enable the production of a large-area photoconductor plate. High-yield PC blocks 110E and 120E are obtained and molded from PC boules and composited with each other by a process (shown by 125E and 130E, forming a 1×2 PC block 140E). This process is repeated in 145C and 150E using one or more 1×2 blocks to form an N×M array of PC blocks (a 4×2 array is shown in 150E). 150E is processed into a plate by a sawing process in 160C and pulverized by 170E to form a large-area PC plate 80E. Advantageously, this allows for the production of a large-area PC plate without the need to grow large-diameter boules.

[0045] In combination with the phase-shifting light bulb system described above, a wide range of lasers across various wavelengths can be used. In some embodiments, the types of lasers that can be used include, but are not limited to, gas lasers, chemical lasers, dye lasers, metal vapor lasers, solid-state lasers (e.g., fiber), semiconductor (e.g., diode) lasers, free-electron lasers, gas dynamic lasers, "nickel-like" samarium lasers, Raman lasers, or nuclear pump lasers.

[0046] Gas lasers can include lasers such as helium-neon lasers, argon lasers, krypton lasers, xenon ion lasers, nitrogen lasers, carbon dioxide lasers, carbon monoxide lasers, or excimer lasers.

[0047] Chemical lasers can include lasers such as hydrogen fluoride lasers, deuterium fluoride lasers, COIL (chemical oxygen-iodine lasers), or Agil (all-gas phase iodine lasers).

[0048] Metal vapor lasers may include lasers such as helium-cadmium (HeCd) metal vapor lasers, helium-mercury (HeHg) metal vapor lasers, helium-selenium (HeSe) metal vapor lasers, helium-silver (HeAg) metal vapor lasers, strontium vapor lasers, neon-copper (NeCu) metal vapor lasers, copper vapor lasers, gold vapor lasers, or manganese (Mn / MnCl2) vapor lasers. Alkali metal vapor lasers such as rubidium can also be used. Solid-state lasers include ruby ​​lasers, Nd:YAG lasers, NdCrYAG lasers, Er:YAG lasers, neodymium YLF (Nd:YLF) solid-state lasers, neodymium-doped yttrium orthobanadate (Nd:YVO4) lasers, neodymium-doped yttrium calcium oxoborate (Nd:YCa4O(BO3)3 or simply Nd:YCOB), neodymium glass (Nd:glass) lasers, titanium sapphire (Ti:sapphire) lasers, and thulium YAG (Tm:YAG) lasers. Lasers include ytterbium YAG (Yb:YAG) lasers, ytterbium:2O3 (glass or ceramic) lasers, ytterbium-doped glass lasers (rods, plates / tips, and fibers), holmium YAG (Ho:YAG) lasers, chromium ZnSe (Cr:ZnSe) lasers, cerium-doped lithium strontium (or calcium) aluminum fluoride (Ce:LiSAF, Ce:LiCAF), and promethium-147 doped glass (147Pm). +3 This may include lasers such as glass solid-state lasers, chromium-doped chrysoberyl (alexandrite) lasers, erbium-doped and erbium-ytterbium co-doped glass lasers, trivalent uranium-doped calcium fluoride (U:CaF2) solid-state lasers, divalent samarium-doped calcium fluoride (Sm:CaF2) lasers, or F-center lasers.

[0049] Semiconductor lasers can include laser medium types such as GaN, InGaN, AlGaInP, AlGaAs, InGaAsP, GaInP, InGaAs, InGaAsO, GaInAsSb, lead salts, vertical cavity surface-emitting lasers (VCSELs), quantum cascade lasers, hybrid silicon lasers, or combinations thereof.

[0050] Figure 2 illustrates the use of a large-area light bulb, as disclosed herein, in an additive manufacturing system 200. A laser source 202 directs a laser beam to the large-area light bulb 206 via a laser preamplifier and / or amplifier 204. After patterning, the light can be directed to the printing floor 210. In some embodiments, heat or laser energy from the laser source 202, laser preamplifier and / or amplifier 204, or the large-area light bulb 206 can be actively or passively transferred to heat transfer, heat engines, cooling systems, and beam dumps 208. The overall operation of the light bulb-based additive manufacturing system 200 can be controlled by one or more controllers 220 that can change the laser output and timing.

[0051] In some embodiments, various preamplifiers or amplifiers 204 can be optionally used to provide high gain to the laser signal, along with distributing optical modulators and isolators throughout the system to reduce or avoid optical damage, improve signal contrast, and prevent damage to the lower energy portion of the system 200. Optical modulators and isolators may include, but are not limited to, Pockels cells, Faraday rotors, Faraday isolators, acousto-optic reflectors, or volume Bragg gratings. The preamplifier or amplifier 204 is often a diode-pumped amplifier or a flashlamp-pumped amplifier and can be configured in single-pass and / or multi-pass or cavity-type architectures. To be understood, the term preamplifier as used herein is used to refer to an amplifier that is less thermally limited (i.e., smaller) compared to a (larger) laser amplifier. The amplifier is typically positioned to be the final unit in the laser system 200 and will be the first module susceptible to thermal damage such as thermal breakdown or excessive thermal lensing effects, but is not limited to these.

[0052] Laser preamplifiers can include single-pass preamplifiers usable in systems where energy efficiency is not a major concern. For more energy-efficient systems, multi-pass preamplifiers can be configured to extract more energy from each preamplifier 204 before proceeding to the next stage. The number of preamplifiers 204 required for a particular system is defined by the system requirements and the available stored energy / gain at each amplifier module. Multi-pass preamplification can be achieved by angular multiplexing or polarization switching (e.g., using waveplates or Faraday rotators).

[0053] Alternatively, the preamplifier may include a cavity structure with a regenerative amplifier type configuration. While such a cavity structure may limit the maximum pulse length due to typical mechanical considerations (cavity length), in some embodiments, a "white cell" cavity can be used. A "white cell" is a multipath cavity architecture in which a small angular shift is added to each pass. By providing inlet and outlet paths, such a cavity can be designed to have a very large number of passes between the inlet and outlet, enabling high gain and efficient use of the amplifier. An example of a white cell is a confocal cavity in which the beam is injected slightly off-axis and the mirror is tilted, so that after many passes, the reflections create a ring pattern on the mirror. The number of passes can be changed by adjusting the injection and mirror angles.

[0054] The amplifier is also used to provide sufficient stored energy to meet the system energy requirements, and together with it, to support sufficient thermal management to enable operation at the repetition rate required by the system, whether it be a diode or an excited flash lamp. Both the thermal energy and laser energy generated during operation can be directed to heat transfer, a heat engine, a cooling system, and a beam dump 208.

[0055] Amplifiers can be configured in single-pass and / or multi-pass or cavity-type architectures. Amplifiers may include single-pass amplifiers suitable for systems where energy efficiency is not a primary concern. For more energy-efficient systems, multi-pass amplifiers can be configured to extract more energy from each amplifier before proceeding to the next stage. The number of amplifiers required for a particular system is defined by the system requirements and the available stored energy / gain at each amplifier module. Multi-pass preamplification can be achieved by angular multiplexing and polarization switching (waveplates, Faraday rotors). Alternatively, amplifiers may include cavity structures with regenerative amplifier-type configurations. Amplifiers can be used for output amplification, as discussed with respect to preamplifiers.

[0056] In some embodiments, the thermal and laser energy generated during the operation of system 200 can be directed to heat transfer, a heat engine, a cooling system, and a beam dump 208. Alternatively, or in addition, in some embodiments, the beam dump 208 may be part of a heat transfer system to provide heat useful for other industrial processes. In yet another embodiment, the heat can be used to energy a heat engine suitable for generating mechanical, thermoelectric, or electrical forces. In some embodiments, waste heat can be used to raise the temperature of connected components. As understood, in this architecture, the laser beam and energy can be scaled by adding more preamplifiers and amplifiers with appropriate thermal management and optical isolation. The heat removal characteristics of the cooling system can be adjusted, and increasing the pump speed or changing the cooling efficiency is used to adjust performance.

[0057] Figure 3 shows an additive manufacturing system 300 capable of accommodating a large-area light bulb as described herein. As seen in Figure 3, the laser source and amplifier 312 may include the large-area light bulb and laser amplifier, as well as other components as described above. As shown in Figure 3, the additive manufacturing system 300 uses a laser capable of providing one-dimensional or two-dimensional directional energy as part of a laser patterning system 310. In some embodiments, one-dimensional patterning can be indicated by linear or curved strips, raster lines, spiral lines, or any other suitable form. Two-dimensional patterning may include isolated or overlapping tiles, or images with varying laser intensity. Two-dimensional image patterns with non-square boundaries may be used, overlapping or interpenetrating images may be used, and the image may be provided by two or more energy patterning systems. The laser patterning system 310 uses the laser source and amplifier 312 to direct one or more continuous or intermittent energy beams into a beam shaping optical system 314. After shaping, the beam is patterned by a laser patterning unit 316, which includes a transmissive or reflective light bulb, as needed, and generally, some of the energy is directed to a rejection energy processing unit 318. The rejection energy processing unit can utilize the heat provided by the active cooling of the light.

[0058] The patterned energy is relayed by an image relay 320 toward an article processing unit 340 in one embodiment as a two-dimensional image 322 focused near the floor 346. The floor 346 (having an optional wall 348) can form a chamber containing material 344 (e.g., metal powder) dispensed by a material dispenser 342. The patterned energy directed by the image relay 320 can modify the dispensed material 344 chemically or physically, by melting, fusing, sintering, bonding, changing the crystal structure, influencing the stress pattern, or otherwise, to form a structure with desired properties. The control processor 350 can be connected to various sensors, actuators, heating or cooling systems, monitors, and controllers to coordinate the operation of the laser source and amplifier 312, beam shaping optics 314, laser patterning unit 316, and image relay 320, and other components of the system 300. As understood, the connections can be wired or wireless, continuous or intermittent, and have a feedback function (e.g., thermal heating can be adjusted according to the sensed temperature).

[0059] In some embodiments, the beam shaping optical system 314 can include a wide variety of imaging optical systems to shape and direct one or more laser beams received from the laser source and amplifier 312 toward the laser patterning unit 316 in a manner that involves coupling, focusing, diverging, reflecting, refraction, homogenizing, adjusting intensity, adjusting frequency, or otherwise shaping the beam. In one embodiment, multiple optical beams, each having a different optical wavelength, can be combined using wavelength-selective mirrors (e.g., dichroism) or diffracting elements. In other embodiments, multiple beams can be homogenized or combined using polyfaceted mirrors, microlenses, and refraction or diffracting optical elements.

[0060] The laser patterning unit 316 may include static or dynamic energy patterning elements. For example, the laser beam may be blocked by a mask having fixed or movable elements. To increase the flexibility and ease of image patterning, pixel-addressable masking, image generation, or transmission may be used. In some embodiments, the laser patterning unit includes an addressable light bulb that provides patterning, either alone or in combination with other patterning mechanisms. The light bulb may use transmissive, reflective, or a combination of transmissive and reflective elements. The pattern may be dynamically modified using electrical or optical addressing. In one embodiment, an optically addressed transmissive light bulb acts to rotate the polarization of the light passing through the bulb, and the optically addressed pixels form a pattern defined by the light projection source. In another embodiment, an optically addressed reflective light bulb includes a write beam for changing the polarization of the read beam. In certain embodiments, an optically unaddressed light bulb may be used. These may include, but are not limited to, electrically addressable pixel elements, movable mirrors or micromirror systems, piezo or microactuated optical systems, fixed or movable masks, or shields, or other conventional systems capable of providing high-intensity light patterning.

[0061] The rejection energy processing unit 318 is used to disperse, redirect, or utilize energy that is not patterned and does not pass through the image relay 320. In one embodiment, the rejection energy processing unit 318 may include passive or active cooling elements to remove heat from both the laser source, light bulb, and amplifier 312 and the laser patterning unit 316. In other embodiments, the rejection energy processing unit may include a "beam dump" to absorb beam energy not used to define the laser pattern and convert it into heat. In yet another embodiment, the rejection laser beam energy can be reused using the beam shaping optics 314. Alternatively, or in addition to the above, the rejection beam energy can be directed to the article processing unit 340 for heating or further patterning. In certain embodiments, the rejection beam energy can be directed to an additional energy patterning system or article processing unit.

[0062] In one embodiment, a “switchyard” style optical system can be used. Switchyard systems are suitable for reducing wasted light in additive manufacturing systems, which results from the rejection of unwanted light by the pattern being printed. A switchyard involves the redirection of a complex pattern from the generation of the complex pattern (in this case, a plane to which a spatial pattern is imparted to a structured or unstructured beam) to delivery via a series of switch points. Each switch point can change the spatial profile of the incident beam as needed. Switchyard optical systems can be used, for example, in laser-based additive manufacturing techniques that apply a mask to light, without limitation. Advantageously, in various embodiments according to this disclosure, the wasted energy can be reused in a homogenized form or as patterned light used to maintain high power efficiency or high throughput rates. Furthermore, the wasted energy can be reused and reused to increase intensity and print more difficult materials.

[0063] The image relay 320 can receive a patterned image (one-dimensional or two-dimensional) directly from the laser patterning unit 316 or via a switchyard and guide it to the article processing unit 340. In a similar manner to the beam shaping optics 314, the image relay 320 may include optics for shaping and directing the patterned light by coupling, focusing, diverging, reflecting, refraction, intensity adjustment, frequency adjustment, or other means. The patterned light can be directed using movable mirrors, prisms, diffractive optical elements, or solid-state optics that do not require substantial physical movement. One of a plurality of lens assemblies may be configured to provide incident light with a magnification ratio, and the lens assembly comprises both a first set and a second set of optical lenses, the second set of optical lenses being interchangeable from the lens assembly. The incident light from the leading mirror can be directed to a desired location using one or more sets of mirrors mounted on a compensating gantry and the rotation of the final mirror mounted on a construction platform gantry. The translational motion of the compensating gantry and the construction platform gantry can also ensure that the distance of the incident light from the leading mirror to the article processing unit 340 is substantially equivalent to the image distance. In effect, this allows for rapid changes in the delivery size and intensity of the light beam across different material construction areas while ensuring high system availability.

[0064] The material processing unit 340 may include a walled chamber 348 and a floor 344 (collectively defining the constructed chamber) and a material dispenser 342 for dispersing materials. The material dispenser 342 can disperse, remove, mix, impart gradations or variations in material type and particle size, or adjust the thickness of the material layer. The materials may include metals, ceramics, glass, polymer powders, other soluble materials that can undergo a thermally induced phase change from solid to liquid and then back again, or combinations thereof. The materials may further include composite materials of soluble and insoluble materials, in which either or both components can be selectively targeted by an imaging relay system to melt the molten components while leaving the insoluble materials to vaporize / destroy / burn or undergo other destruction processes. In certain embodiments, slurries, sprays, coatings, wires, strips, or material sheets may be used. Unwanted material can be removed for single use or reuse using a blower, vacuum system, sweeping, vibration, shaking, tilting, or inversion of the floor 346.

[0065] The material handling unit 340 may include, in addition to components for handling materials, components for holding and supporting the 3D structure, mechanisms for heating or cooling the chamber, auxiliary or support optics, and sensors and control mechanisms for monitoring or adjusting material or environmental conditions. The material handling unit may support a vacuum or inert gas atmosphere, in whole or in part, to reduce unwanted chemical interactions and mitigate the risk of fire or explosion (especially with reactive metals). In some embodiments, various pure or other mixtures of atmosphere may be used, including Ar, He, Ne, Kr, Xe, CO2, N2, O2, SF6, CH4, CO, N2O, C2H2, C2H4, C2H6, C3H6, C3H8, i-C4H 10 C4H 10 , 1-C4H8, cic-2, C4H7, 1,3-C4H6, 1,2-C4H6, C5H 12 n-C5H 12 i-C5H 12 n-C6H 14 , C2H3Cl, C7H16 C8H 18 , C 10 H 22 , C 11 H 24 , C 12 H 26 , C 13 H 28 , C 14 H 30 , C 15 H 32 , C 16 H 34 , C6H6, C6H5-CH3, C8H 10 This includes those containing C2H5OH, CH3OH, and iC4H8. In some embodiments, a refrigerant or large inert molecules (including but not limited to sulfur hexafluoride) can be used. An enclosure atmosphere composition having at least about 1% He by volume (or number density) can be used, along with a selected percentage of inert / unreactive gas.

[0066] In certain embodiments, multiple article processing units or construction chambers, each having a construction platform for holding a powder bed, can be used in combination with multiple optical mechanical assemblies positioned to receive and direct one or more incident energy beams into the construction chambers. Multiple chambers allow for the simultaneous printing of one or more print jobs within one or more construction chambers. In other embodiments, removable chamber sidewalls can simplify the removal of printed objects from the construction chambers, enabling rapid replacement of powder materials. The chambers may also be equipped with adjustable process temperature control. In yet another embodiment, the construction chamber can be configured as a removable printer cartridge that can be positioned near the laser optics. In some embodiments, the removable printer cartridge may contain powder or support a removable connection to a powder supply source. After the article is manufactured, the removable printer cartridge can be removed and replaced with a new one.

[0067] In another embodiment, one or more article processing units or construction chambers may have a construction chamber maintained at a fixed height, while the optics can move vertically. The distance between the final optics of the lens assembly and the top surface of the powder bed a can be controlled to be essentially constant by indexing the final optics upward by a distance equivalent to the thickness of the powder layer, while keeping the construction platform at a fixed height. Advantageously, this makes it easier to manufacture large and heavy objects because it eliminates the need for precise micron-scale movement of the constantly changing mass of the construction platform compared to moving the construction platform vertically. Typically, construction chambers dealing with metal powders in volumes exceeding approximately 0.1–0.2 cubic meters (i.e., more than 100–200 liters or heavier than 500–1,000 kg) benefit most from keeping the construction platform at a fixed height.

[0068] In one embodiment, a portion of the powder bed layer may be selectively melted or fused to form one or more temporary walls from the fused portion of the powder bed layer, which may include another portion of the powder bed layer on the construction platform. In a selected embodiment, fluid passages may be formed in one or more first walls to enable improved thermal management.

[0069] In some embodiments, the lamination manufacturing system may include an article handling unit or construction chamber having a construction platform supporting a powder bed that can be tilted, inverted, and shaken to substantially separate the powder bed from the construction platform within a hopper. The powdery material forming the powder bed may be recovered into the hopper for reuse in a later printing job. The powder recovery process may be automated, and vacuum or gas jet systems may also be used to assist in the discharge and removal of the powder.

[0070] In some embodiments, the lamination manufacturing system can be configured to easily handle parts longer than the available construction chamber. A continuous (long) part can be sequentially advanced longitudinally from a first zone to a second zone. In the first zone, granules of selected granular material can be bonded. In the second zone, unbonded granules of the granular material can be removed. The first part of the continuous part can proceed from the second zone to the third zone, while the last part of the continuous part is formed within the first zone, and the first part is maintained in the same lateral and transverse position that the first part occupied within the first and second zones. In practice, lamination manufacturing and cleanup (e.g., separation and / or regeneration of unused or unbonded granular material) can be performed in parallel (i.e., simultaneously) at different locations or zones on the part conveyor without the need to stop for the removal of granular material and / or parts.

[0071] In another embodiment, the lamination manufacturing capability can be improved by using an enclosure that restricts the exchange of gaseous material between the inside and outside of the enclosure. The airlock provides an interface between the inside and outside and has multiple lamination manufacturing chambers inside, including one that supports powered bed fusion. A gas management system maintains the gaseous oxygen inside below a limiting oxygen concentration, increasing the flexibility of the powder types and processing that can be used in the system.

[0072] In another manufacturing embodiment, capacity can be improved by housing an article processing unit or construction chamber within an enclosure, allowing the construction chamber to produce parts weighing 2,000 kilograms or more. A gas management system can maintain gaseous oxygen within the enclosure at concentrations below atmospheric levels. In some embodiments, an airlock acts as a buffer between the gas environment inside and outside the enclosure, and operates in locations outside both the enclosure and the airlock, allowing a wheeled vehicle to transport parts from inside the enclosure through the airlock.

[0073] Other manufacturing embodiments include collecting powder samples from the powder bed in real time. The Ingester system is used for in-process collection and characterization of powder samples. Collection can be performed periodically, and the results of the characterization are used to adjust the powder bed fusion process. The Ingester system can be used, as needed, for one or more actions such as auditing, process adjustment, or verifying the proper use of licensed powder materials, such as changing printer parameters or ensuring proper use of licensed powder materials.

[0074] It is explained that further improvements to the additive manufacturing process are possible by using manipulator devices such as cranes, lifting gantry, and robotic arms, or by enabling the manipulation of parts that are difficult or impossible to move by humans. Manipulator devices can grasp various operating points that are permanently or temporarily additively manufactured on a part, enabling the repositioning and manipulation of the part.

[0075] The control processor 350 can be connected to control any component of the additive manufacturing system 300 described herein, including lasers, laser amplifiers, optics, thermal control, construction chambers, and manipulator devices. The control processor 350 can be connected to a variety of sensors, actuators, heating or cooling systems, monitors, and controllers to coordinate their operation. A wide range of sensors, such as imagers, light intensity monitors, thermal sensors, pressure sensors, or gas sensors, can be used to provide information used for control and monitoring. The control processor may be a single central controller or, instead, may include one or more independent control systems. The controller processor 350 is provided with an interface that allows for the input of manufacturing instructions. The use of a wide range of sensors enables various feedback control mechanisms to improve quality, manufacturing throughput, and energy efficiency.

[0076] Figure 4 shows one embodiment of the operation of a manufacturing system supporting the use of a large-area light bulb suitable for lamination or removal manufacturing. In this embodiment, flowchart 400 shows one embodiment of a manufacturing process supported by the described optical and mechanical components. In step 402, the material is placed on a floor, chamber, or other suitable support. The material may be a metal sheet for laser cutting using removal manufacturing techniques, or a powder that can be modified by lamination manufacturing techniques in a way that involves melting, fusing, sintering, induction to change the crystalline structure, being affected by stress patterns, or otherwise chemically or physically to form a structure with desired properties.

[0077] In step 404, unpatterned laser energy is emitted by one or more energy emitters, including but not limited to solid-state or semiconductor lasers, and then amplified by one or more laser amplifiers. In step 406, the unpatterned laser energy is shaped and modified (e.g., intensity modulation or focusing). In step 408, this unpatterned laser energy is patterned by a large-area light bulb, and the energy that does not form part of the pattern is processed in step 410 (this may include the use of beam dumps disclosed with respect to Figures 2 and 3, which allow for conversion to waste heat, reuse as patterned or unpatterned energy, or dissipation of heat generated by cooling the laser amplifiers in step 404). In step 412, the patterned energy, which here forms a one-dimensional or two-dimensional image, is relayed to the material. In step 414, the image is applied to the material, and parts of the 3D structure are removed or built up layer by layer. In additive manufacturing, these steps can be repeated until the image (or different images and subsequent images) is applied to all the desired areas of the top layer of the material (loop 416). Once the application of energy to the top layer of material is complete, a new layer can be applied (loop 418) to continue building the 3D structure. These process loops continue until the 3D structure is complete, provided that any remaining excess material can be removed or reused.

[0078] Figure 5 shows one embodiment of an additive manufacturing system including a large-area light bulb and switchyard system that enables the reuse of patterned two-dimensional energy. The additive manufacturing system 520 has an energy patterning system with a laser and amplifier source 512 that directs one or more continuous or intermittent laser beams to a beam-forming optical system 514. Excess heat can be transferred to a rejection energy processing unit 522, which may include an active light bulb cooling system disclosed with respect to Figures 2, 3, and 4. After shaping, the beam is patterned two-dimensionally by the energy patterning unit 530, and generally, some of the energy is directed to the rejection energy processing unit 522. The patterned energy is relayed by one of a plurality of image relays 532 to one or more article processing units 534A, 534B, 534C, or 534D as a two-dimensional image typically focused near a floor of a movable or fixed height. The floor may be in a cartridge containing a powder hopper or similar material dispenser. The patterned laser beam directed by the image relay 532 can modify the dispensed material chemically or physically by melting, fusing, sintering, bonding, changing the crystal structure, influencing the stress pattern, or otherwise, to form a structure with desired properties.

[0079] In this embodiment, the rejected energy processing unit has multiple components to enable the reuse of rejected patterned energy. Cooling fluid from the laser amplifier and laser source 512 can be directed to one or more of the generator 524, the heating / cooling thermal management system 525, or the energy dump 526. Furthermore, relays 528A, 528B, and 528C can transfer energy to the generator 524, the heating / cooling thermal management system 525, or the energy dump 526, respectively. Optionally, relay 528C can direct the patterned energy to image relay 532 for further processing. In other embodiments, the patterned energy can be directed by relay 528C to relays 528B and 528A and inserted into the laser beam provided by the laser and amplifier source 512. Reuse of the patterned image is also possible using image relay 532. The image can be redirected, inverted, mirrored, sub-patterned, or otherwise transformed for distribution to one or more item processing units 534A-D. Advantageously, the reuse of patterned light can improve the energy efficiency of the lamination manufacturing process, improve the energy intensity directed to the floor in some cases, or reduce manufacturing time.

[0080] Many modifications and other embodiments of the present invention will come to mind for those skilled in the art who are interested in the teachings shown in the above description and the associated drawings. Therefore, it is understood that the present invention is not limited to the specific embodiments disclosed, and that modifications and embodiments are intended to be included within the scope of the appended claims. It is also understood that other embodiments of the present invention can be carried out even without elements / steps not specifically disclosed herein.

Claims

1. circuit board and At least two photoconductor plates attached to the substrate and Equipped with, A light bulb in which the at least two photoconductor plates mounted on the substrate are arranged laterally to each other, polished as a single component, and have a uniform thickness across the at least two photoconductor plates.

2. The light bulb according to claim 1, wherein the substrate includes sapphire.

3. The light bulb according to claim 1, wherein the at least two photoconductor plates are attached to the substrate with a glass adhesive.

4. The light bulb according to claim 1, wherein the at least two photoconductor plates are further combined with a linear electrical (LEO) assembly and mounted on a secondary substrate.

5. The light bulb according to claim 1, wherein the at least two photoconductor plates include at least one of bismuth silicate, bismuth germanate, cadmium selenide, chalcogenide glass, polycrystalline material, or amorphous silicon.

6. The at least two photoconductive plates are BSO, Bi １２ SiO ２０ , Bi ６ SiO １０ , Bi ３ SiO ５ , bismuth germanate, BGO, Bi １２ GeO ２０ , Bi ６ GeO １０ , Bi ３ GeO ５ , CdSe, Ge ２ Sb ２ Te ５ (GST), Sc ０．２ Sb ２ Te ３ , GeTe, Ag ４ In ３ Sb ６７ Te ２６ , Ge １５ Sb ８５ , Sb, CdTe, AZO, ZnSe, ZnS, or Si, and the light valve according to claim 1.

7. The light bulb according to claim 1, wherein the at least two photoconductor plates are included in an N×M array on the substrate.

8. The light bulb according to claim 1, wherein each of the at least two photoconductor plates has a linear electro-optic (LEO) layer and a transparent conductive oxide (TCO) layer.

9. A laser light source for forming a laser beam, A light bulb that supports the two-dimensional patterning of the laser beam, comprising a substrate and at least two photoconductor plates attached to the substrate, and Equipped with, A laminated manufacturing system in which the at least two photoconductor plates mounted on the substrate are arranged laterally to each other, polished as a single component, and have a uniform thickness across the at least two photoconductor plates.

10. The laminate manufacturing system according to claim 9, wherein the substrate includes sapphire.

11. The laminated manufacturing system according to claim 9, wherein the at least two photoconductor plates are attached to the substrate with a glass adhesive.

12. The laminated manufacturing system according to claim 9, wherein the at least two photoconductor plates are further combined with a linear electrical (LEO) assembly and mounted on a secondary substrate.

13. The laminated manufacturing system according to claim 9, wherein the at least two photoconductor plates include at least one of bismuth silicate, bismuth germanate, cadmium selenide, chalcogenide glass, polycrystalline material, or amorphous silicon.

14. The at least two photoconductor plates are BSO, Bi １２ SiO ２０ , Bi ６ SiO １０ , Bi ３ SiO ５ , bismuth germanate, BGO, Bi １２ GeO ２０ , Bi ６ GeO １０ , Bi ３ GeO ５ ,CdSe,Ge ２ Sb ２ Te ５ (GST), Sc ０．２ Sb ２ Te ３ GeTe, Ag ４ In ３ Sb ６７ Te ２６ , Ge １５ Sb ８５ The lamination manufacturing system according to claim 9, comprising at least one of Sb, CdTe, AZO, ZnSe, ZnS, or Si.

15. The laminated manufacturing system according to claim 9, wherein the at least two photoconductor plates are included in an N×M array on the substrate.

16. The laminated manufacturing system according to claim 9, wherein each of the at least two photoconductor plates has a linear electro-optic (LEO) and a transparent conductive oxide (TCO) layer containing these layers.

Images