Printhead conditioning device, system, and method

Abstract

A printing system includes a printhead carriage that supports a printhead and is mounted to translate along a crossbeam that extends in an x-axis direction of an x-axis, y-axis, z-axis Cartesian coordinate system. A method of controlling a printing system includes sensing one or more of a rotational orientation of the printhead about the x-axis, y-axis, and z-axis and a position of the printhead along the y-axis and z-axis. Based on the sensed one or more of the rotational orientation and the position, adjusting a position of one or more bearings arranged to support the printhead carriage on the crossbeam. Adjusting the position of the one or more bearings will adjust one or both of the rotational orientation of the printhead and the position of the printhead. Systems and methods related to printing system control.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 701,529, filed July 20, 2018, and U.S. Provisional Patent Application No. 16 / 515,580, filed July 18, 2019, the entire contents of which are incorporated herein by reference. Background Technology

[0003] The present invention relates to apparatus, systems and methods for providing fine adjustment of printhead position and orientation, for example, for use in industrial printing systems for manufacturing devices (e.g., displays).

[0004] Manufacturing various electronic devices using inkjet printing technology typically benefits from the high accuracy of ink droplet placement to achieve functional products that meet quality expectations. Examples of such devices include, but are not limited to, microchips, printed circuit boards, solar cells, electronic displays (such as liquid crystal displays, organic light-emitting diode displays, and quantum dot electroluminescent displays), or other devices. In the example application of using inkjet printing to manufacture organic light-emitting diode (OLED) displays, organic materials (sometimes called organic inks) are printed onto a substrate to form pixels. The manufacture of such devices, as well as other devices as exemplified above, presents various challenges. For example, regardless of whether inkjet printing, thermal printing, or other techniques are used, it is difficult to control the deposition of organic or other ink materials at desired locations in a precise, accurate, and reproducible manner to achieve uniform deposition at the desired locations. Improvements to existing systems and technologies are needed to achieve these goals.

[0005] In display devices such as OLED displays, for example, as resolution increases and pixel sizes decrease accordingly, the accuracy and precision of printed components, such as the printhead, become increasingly important for maintaining the quality of the final device. Various devices, systems, and methods are needed to facilitate accurate and precise positioning and orientation of printed components, such as the position and orientation of the printhead relative to the substrate on which material is to be deposited, to provide precise droplet placement. Precise droplet placement can, in turn, improve the resolution of the final product and reduce material waste during manufacturing. Furthermore, it is desirable to provide devices and methods configured to improve the efficiency of the manufacturing process and reduce (e.g., minimize) the overall complexity and weight of the associated printing apparatus. Summary of the Invention

[0006] According to various exemplary embodiments of this disclosure, a printing system includes a printhead carriage that supports a printhead and is mounted to translate along a beam extending in the x-axis direction of a Cartesian coordinate system of x, y, and z axes. A method of controlling a printing system includes sensing one or more of the direction of rotation of a printhead about the x, y, and z axes and the position of the printhead along the y and z axes. Based on one or more of the sensed direction of rotation and position, the position of one or more bearings arranged to support the printhead carriage on the beam is adjusted. Adjusting the position of the one or more bearings can adjust one or both of the direction of rotation and the position of the printhead.

[0007] In yet another exemplary embodiment of this disclosure, a method for controlling a printing system includes: sensing information relating to the position of a printhead along a travel path extending along the x-axis; sensing information relating to one or more of the rotational direction of the printhead about the x-, y-, and z- axes and the position of the printhead along the y- and z- axes; adjusting one or both of the rotational direction and position of the printhead by adjusting the position of one or more bearings of a printhead carriage carrying the printhead; and storing information relating the position of one or more bearings of the printhead carriage to the corresponding position of the printhead carriage along the travel path.

[0008] In another exemplary embodiment of this disclosure, the printing system includes a substrate support system configured to support a substrate having a surface to be printed. The substrate support system is configured to hold the surface to be printed in an xy-plane substantially perpendicular to the z-axis of a Cartesian coordinate system. The system includes a beam extending through the substrate support system in the x-axis direction, and a printhead carriage movably coupled to the beam for movement in the x-axis direction, the printhead carriage including one or more bearings positioned relative to the beam to support the printhead carriage. At least one of the one or more bearings is coupled to an actuator selectively adjustable to adjust one or more of the rotational directions of the printhead carriage about the x, y, and z axes, and the position of the printhead carriage in the y-axis and z-axis directions.

[0009] Other objects, features, and / or other advantages will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this disclosure and / or the claims. At least some of these objects and advantages may be realized and obtained by means of the elements and combinations particularly pointed out in the appended claims.

[0010] The foregoing general description and the following detailed description are exemplary and explanatory only and do not limit the claims; rather, the claims shall enjoy the full scope of their rights, including equivalents. Attached Figure Description

[0011] Figure 1 This is a perspective view of a printing assembly for an industrial printing system according to an exemplary embodiment of the present disclosure.

[0012] Figure 2 This is a perspective view of a printhead carriage according to an exemplary embodiment of the present disclosure.

[0013] Figure 3A This is a schematic plan view of a printhead and carriage assembly according to exemplary embodiments of the present disclosure.

[0014] Figure 3B yes Figure 3A The printhead and carriage assembly from Figure 3B A schematic plan view of the direction of rotation shown.

[0015] Figure 4 This is a schematic side view of a gas bearing and actuator according to an exemplary embodiment of the present disclosure.

[0016] Figure 5 This is a schematic side view of a gas bearing and actuator according to another exemplary embodiment of the present disclosure.

[0017] Figure 6 This is a schematic side view of a gas bearing and actuator according to yet another exemplary embodiment of the present disclosure.

[0018] Figure 7 This is a block diagram of a control system for a printing system according to an exemplary embodiment of the present disclosure.

[0019] Figure 8 This is a flowchart illustrating a method for controlling a printing system according to an exemplary embodiment of the present disclosure.

[0020] Figure 9 This is a flowchart illustrating a method for calibrating a printing system according to another embodiment of the present disclosure.

[0021] Figure 10 This is a flowchart illustrating a method for controlling a printing system according to another embodiment of the present disclosure.

[0022] Figure 11 This is a schematic perspective view of a substrate and a printhead according to an exemplary embodiment of the present disclosure.

[0023] Figure 12 This is a schematic side view (shown in cross-section) of the carriage and printhead relative to a crossbeam according to another exemplary embodiment of this disclosure.

[0024] Figure 13 It is based on Figure 12A schematic cross-sectional view of the carriage and printhead in an exemplary embodiment, the cross-section being perpendicular to... Figure 12 It is cut off from the plane of the cross-section plane.

[0025] Figure 14 It is based on Figure 12 A schematic cross-sectional view of the carriage and printhead in an exemplary embodiment, to be consistent with... Figure 13 The same view is shown.

[0026] Figure 15 It is based on Figure 12 A schematic cross-sectional view of the carriage and printhead in an exemplary embodiment, to be consistent with... Figure 12 The same view is shown. Detailed Implementation

[0027] Various exemplary embodiments of this disclosure provide apparatus, systems, and methods for adjusting the orientation of a printhead, for example, to improve the accuracy of one or both of the orientation (e.g., rotation about an axis) and position (e.g., translation along an axis) of the printhead relative to a surface on which material is deposited using the printhead. For example, various exemplary embodiments of this disclosure provide fine-tuning of one or more of three rotational directions of the printhead about one or more of three Cartesian axes, and fine-tuning of one or more of two translational positions about two Cartesian axes. For the sake of brevity, some embodiments disclosed herein discuss adjustment of the orientation about a single rotational axis. For example, with those disclosed herein… Figure 1 The embodiments described in section 3 discuss adjustment of the rotational direction of the printhead about an axis extending perpendicular to the printing surface of the substrate, referred to herein as "θ-z" adjustment. Other disclosed embodiments are configured to provide rotational direction adjustment about any or all Cartesian (x, y, and z) axes, as well as translational position adjustment about any two of the three Cartesian axes, which are perpendicular to the printhead's travel direction defined along a third Cartesian axis.

[0028] The exemplary embodiments disclosed herein offer significant advantages over other possible methods for achieving printhead adjustment. For example, in one possible method providing directional adjustment about a rotation axis, the printhead may be mounted on a rotating disk capable of rotating (e.g., rapidly rotating) the printhead about an axis perpendicular to the printing surface of the substrate. However, such mechanisms tend to be bulky and expensive, and may be difficult to integrate into the overall printing system due to their size and weight.

[0029] An alternative to mounting the printhead on a turntable or other rotating device is to provide a means or system for adjusting the orientation of the substrate so as to adjust the angular direction of the printing surface of the substrate relative to an axis perpendicular to the printing surface of the substrate. Such a substrate orientation adjustment mechanism may, for example, be part of a substrate transport system that moves the substrate during printing. This system may be more complex than a substrate transport system not configured to make such θ-z adjustments to the orientation of the printing surface of the substrate, and may cause inaccuracies in other aspects of the overall substrate positioning, such as, for example, in the x and y directions. Various exemplary embodiments of this disclosure can reduce or eliminate the need for a substrate support system configured to rotate the substrate about the z-axis and include compensating movement along the x-axis. Furthermore, embodiments of this disclosure allow for adjustment with greater degrees of freedom and finer control over the adjustment, thereby providing better precision in ink placement and control.

[0030] Therefore, embodiments of this disclosure can be used with substrate support systems that do not require rotation of the substrate about the θ-z axis to correct for θ-z errors in the printhead orientation, thereby reducing complexity and potentially increasing the accuracy and precision of the substrate support system. However, those skilled in the art will understand that various exemplary embodiments of this disclosure can still be used in conjunction with substrate support and / or substrate transport systems configured to rotate the substrate about the z-axis to provide a combination of methods for achieving relative θ-z adjustment of the printhead and the substrate printing surface. For example, in one exemplary embodiment, the substrate transport system can be used to provide overall control of the substrate orientation, while an adjustable printhead carriage can be used for fine control of the printhead orientation relative to the substrate.

[0031] This disclosure measures various exemplary embodiments of a printhead and carriage assembly that can rotate about one or more axes to change the direction of rotation of the printhead relative to other components of the printing system, including relative to a printing surface. For example, the printhead can be rotated about an axis perpendicular to a printing surface of a substrate on which it deposits organic material to form pixels, thereby achieving relative θ-z adjustment of the printhead and the printing surface.

[0032] In some exemplary embodiments, the printhead carriage includes a plurality of bearings configured to support the printhead carriage and the attached printhead on a crossbeam (sometimes called a frame). The bearings include, for example, gas bearings, magnetic levitation bearings, or other bearings or devices that reduce or minimize contact between the crossbeam and the carriage while holding the carriage in a desired position and orientation relative to the crossbeam. For example, the bearings may be configured to allow the carriage to translate along the crossbeam with a single degree of freedom.

[0033] According to an exemplary embodiment of this disclosure, the position of one or more bearings relative to the carriage can be changed to alter the direction of rotation of the carriage relative to the crossbeam, and thus relative to one or more of the three Cartesian axes. For example, one or more bearings can be moved relative to the carriage along the bearing's longitudinal axis (i.e., the axis oriented perpendicular to the bearing's surface facing the crossbeam) to change the bearing's orientation. In some embodiments, the bearings are supported on the carriage by ball joints that passively rotate such that, as the carriage orientation changes, the bearing surface facing the crossbeam remains parallel to the crossbeam surface.

[0034] In one exemplary embodiment, one or more bearings movable along their longitudinal axis are connected to the carriage via an actuator configured to move the bearings along the longitudinal axis of each bearing. The actuator may be referred to herein as an actuation mechanism. In one exemplary embodiment, the actuator includes a piezoelectric element that changes shape based on the application of an electric current. In other exemplary embodiments, the actuator includes means such as a pneumatic actuator, a hydraulic actuator, or an electromechanical actuator such as a linear motor, a voice coil device, or other means. Optionally, the actuator includes a sensor, such as a position encoder, that provides information (e.g., signals) including actual position information about the actuator. Such information can be used by a controller in a feedback control system to verify the position of the carriage.

[0035] For reference Figure 1 , Figure 1 An exemplary embodiment of a printing system 100 for industrial printing applications is shown. The printing system is shown separately, but those skilled in the art will understand that the printing system may be housed within a housing with a controlled processing environment, and this housing may be part of an overall industrial system for manufacturing various electronic components, including displays (e.g., OLEDs). U.S. Patent Application Publications US2014 / 0311405A1, US2017 / 0028731A1, US2018 / 0014411A1, and U.S. Patent 9,505,245 disclose non-limiting examples of such industrial systems for manufacturing electronic device components, including for printing displays, the entire contents of which are incorporated herein by reference. The printing system 100 includes a substrate support system 102 for supporting a substrate 104. The substrate support system may include, for example, a chuck, such as a vacuum chuck, or a substrate floating chuck having a pressure port, a vacuum port, or a combination thereof. In one exemplary embodiment, the substrate support system 102 includes a substrate floating chuck 106 and a motion system 108 configured to move along… Figure 1The substrate 104 is moved along the y-axis (those skilled in the art will understand that the x-axis and y-axis of the illustrated xyz Cartesian system can be switched, and therefore should not limit the scope of this disclosure; the z-axis is chosen to be perpendicular to the printed surface of the substrate). The motion system may include first and second crossbeams 110, 112 oriented longitudinally along the y-axis, and a device such as a gripper (not shown) may be configured to hold the substrate 104 and move it along the y-axis within the printing area 14. Further details regarding non-limiting examples of configurations of the substrate support system that may be used as the substrate support system 102 can be found in U.S. Patent Application Publications US2017 / 0028731A1, US2014 / 0311405A1, and US2018 / 0014411A1 and U.S. Patent 9505245, each of which is incorporated herein by reference.

[0036] In an area that can be defined as the printing area, the printing system 100 includes a crossbeam 116 (e.g., a gantry or cable tray) located above the substrate support system 102 (the area traversed by the printhead as it crosses the crossbeam 116 will be explained further below). Figure 1 In an exemplary embodiment, one end of the crossbeam 116 is mounted on a first riser 118, and the other end is mounted on a second riser 120, which supports the crossbeam 116 above the printing area. The crossbeam 116 may comprise a stable material that can be dimensionally determined with high accuracy and exhibits rigidity and strength. In a non-limiting example, the crossbeam 116 has a smooth (e.g., polished) surface. The crossbeam 116 may comprise, for example, but not limited to, materials such as ceramic materials, metals or alloys such as aluminum or steel, or composite materials. Figure 1 In an exemplary embodiment, the crossbeam 116 is made of granite.

[0037] The printing system 100 may include one or more printhead carriages 122, which allow the printhead carriages 122 to move in... Figure 1The printhead carriages 122 are connected to the crossbeam 116 in a manner that allows translation along the x-axis. The one or more printhead carriages 122 are configured to carry one or more printheads 124 for depositing material onto the substrate 104. For example, the one or more printheads 124 may be inkjet printheads configured to deposit ink (e.g., organic OLED material) onto the substrate 104. The one or more carriages 122 move along the crossbeam 116 to various positions along the x-axis, positioning the printheads 124 at desired locations for printing on the substrate 104 along the x-axis. Translational movement of the substrate 104 along the y-axis, combined with the translational movement of the carriages 122 along the x-axis, allows the printheads 124 to enter a portion of the substrate 104 along both the x and y axes to print organic material onto a desired area of ​​the substrate 104, for example, to achieve material deposition in a patterned manner on the printed surface. The carriage 122 and the crossbeam 116 can be configured such that the printing surface (not shown) of each printhead 124 remains parallel to the printing surface (the surface facing the crossbeam 116) of the substrate 104. In some exemplary embodiments, the printing system 100 is part of an overall industrial manufacturing system for manufacturing electronic devices, such as substrates used in electronic displays as described above.

[0038] The printing system 100 may also include one or more measuring devices associated with the print head 124. For example, in Figure 1 In this configuration, one or more sensors 119 (e.g., interferometers) are connected to each printhead 124 and associated with an optical system (not shown) configured to measure the actual translational position and / or orientation of the printhead 124 and carriage 122 during calibration or printing, as discussed in more detail below. Although in Figure 1 Only one sensor 119 is shown, but in some exemplary embodiments, the printing system 100 includes multiple measuring devices arranged to determine the direction of rotation of one or more printheads 124 about one or more axes (e.g., about the x-axis, y-axis, or z-axis). In some exemplary embodiments, the printing system 100 includes three separate measuring devices (e.g., a laser interferometer or other optical measuring device) that measure the distances of three known points on the printhead from a plane defined by the surface of the substrate 104. Based on these three distance measurements, the direction of rotation of the printhead 124 about all three axes (e.g., the x-axis, y-axis, and z-axis) can be determined. Similarly, one or more additional measuring devices may be arranged to sense the position of the printhead along two axes perpendicular to the direction of travel of the printhead 124. For example, as... Figure 1 As shown, the position of the print head 124 relative to the crossbeam 116 along the y-axis and z-axis can be determined by additional measuring devices (such as optical sensors or other devices).

[0039] Alternatively or alternatively, the printing system can be calibrated using, for example, a "master glass" (not shown), a glass plate, or a calibration device of other material having the same dimensions as the substrate (such as substrate 104). The master glass includes a pattern of markings with known positions on it. One or more (e.g., two) high-magnification cameras are used to determine the actual position of the markings relative to the intended position of the markings, thereby identifying any errors occurring in the position and / or orientation of the printhead 124. Any such errors are recorded and used to correct the position and / or orientation of the printhead 124 using the system and methods described herein.

[0040] Due to printing system 100 ( Figure 1 The high precision requirements of the printing system 100 mean that small errors in its various components can cause misalignment between one or more printheads 124 and the substrate 104 due to the movement of the printhead carriage 122 along the crossbeam 116 during printing. For example, small variations in the surface of the crossbeam 116, such as those caused by manufacturing tolerances associated with its production, can cause misalignment of the carriage 122. Figure 1 The direction of rotation of the z-axis shown changes as the carriage 122 moves across the crossbeam 116. For example, as the carriage moves along the crossbeam 116, a change in the thickness or flatness of the crossbeam 116 can potentially cause a change in the direction of rotation of the z-axis of the carriage 122. Although such changes in direction may be small (e.g., on the order of microradians), they can still affect printing accuracy (e.g., expected droplet placement and / or trajectory) by altering the intended alignment of the printhead 124 relative to the substrate 104. For example, the nozzles for depositing ink may be oriented from their extended printhead surface and the printing surface of the substrate such that they are not aligned in the θ-z direction as desired. This can lead to inaccurate droplet placement and / or droplet deposition, which may result in uneven drying of the deposited droplets, leading to uneven film thickness in the final product.

[0041] In addition to the change in the z-axis direction of the carriage 122, changes in the thickness or flatness of the crossbeam 116 as the carriage 122 moves along the crossbeam 116 may cause other directional and positional changes. For example, the unsupported length of the crossbeam 116 between the first and second risers 118 and 120 may cause the crossbeam 116 to potentially sag between the first and second risers 118 and 120. This sag of the crossbeam 116 as the carriage 122 moves along the carriage 122 will cause a change in the rotational direction of the carriage 122 about the y-axis. This interruption of the rotational direction about the y-axis may cause the printhead surface to be non-parallel to the printing surface of the substrate. Similarly, this sag may also cause the printhead surface to be closer to the printing surface of the substrate than intended or designed. Likewise, in addition to the z-axis changes described above, changes in the crossbeam thickness, flatness, and straightness may also cause other changes in the rotational direction of the carriage 122 about the x-axis and y-axis. Similarly, the aforementioned changes in the crossbeams and / or other component support parts of the entire system can contribute to positional changes (translations) of the carriage 122 along the y-axis and z-axis. Exemplary embodiments of this disclosure can be configured to compensate for (e.g., correct) directional changes of the carriage 122 and the printhead 124 about the x, y, and z axes, and along two independent axes perpendicular to the direction of movement of the carriage 122 (e.g., ...). Figure 1 The position of the y-axis and z-axis in the diagram.

[0042] For reference Figure 11 It shows a schematic perspective view of substrate 1104. Figure 11 The diagram shows the directional variations about the x, y, and z axes (θ-x, θ-y, and θ-z, respectively) and along the x, y, and z axes (θ-x, θ-y, and θ-z, respectively). T Y T and Z T Translation of X. In an exemplary embodiment of this disclosure, translation X T This indicates that the print head 1124 travels along a path, for example, along the crossbeam 116 ( Figure 1 (The movement of)

[0043] Figure 11 It also illustrates how potential misalignment in the position or orientation of the substrate can lead to misalignment between the printhead and the substrate. Figure 11In the diagram, the solid line shows the substrate 1104 in the first direction. The dashed line shows the substrate 1104 in the second direction, wherein the substrate 1104 is rotated relative to the first direction about one of the x, y, or z axes. In either the x, y, or z axis, the substrate 1104 may also be misaligned by translation relative to the printhead 1124. Such rotation or translation of the substrate 1104 may result in misalignment between the substrate 1104 and the printhead 1124. Alternatively or additionally, misalignment between the substrate 1104 and the printhead 1124 may be the result of rotational misalignment of the printhead 1124 relative to the substrate 1124. The total misalignment between the printhead 1124 and the substrate 1104 may be the sum of the deviation of the substrate 1104 relative to the intended substrate orientation about the x, y, and z axes and its position in the x, y, and z directions, and the deviation of the printhead 1124 relative to the intended printhead orientation about the x, y, and z axes and its position in the y and z directions (where the x direction is the travel direction of the printhead 1124). Exemplary embodiments of this disclosure, such as those in conjunction with Figure 2-10 As shown and described, the carriage 122 ( Figure 1 ) and printhead 124 ( Figure 1 It can be adjusted by rotation and translation along each axis to compensate for this deviation from the intended alignment of the printhead 124 with respect to the substrate.

[0044] For reference Figure 2 The present disclosure illustrates in more detail a printhead carriage 222 according to an exemplary embodiment of the present disclosure. The printhead carriage 222 may include one or more means configured to facilitate the printhead carriage 222 along a crossbeam (e.g., Figure 1 The low-friction movement of the crossbeam 116 in the printhead carriage 222 facilitates precise positioning of the carriage 222 relative to the printed surface of the substrate. In an exemplary embodiment, the printhead carriage 222 includes features configured to enable the carriage 222 to be supported and allow the carriage 222 to move along the crossbeam 116 while minimizing (e.g., reducing or eliminating) friction between the carriage 222 and the crossbeam 116. The carriage 222 includes a printhead mounting portion 223 configured to receive a portion of the printhead (e.g., ...). Figure 1 The print head 124 shown in the figure, and holds the print head in the proper position on the carriage 222 when the carriage 222 crosses the crossbeam 116.

[0045] For example, in Figure 2 In this embodiment, the printhead carriage 222 includes a plurality of gas bearings 226. Each gas bearing 226 has a face facing the crossbeam (e.g., Figure 1 The crossbeam 116 shown is mounted on surface 229, and the gas bearing 226 is configured to receive a supply of pressurized gas (e.g., air or inert gas) and release the gas to the crossbeam and surface 229 (in... Figure 2 A layer of air or other gas is generated between the two visible surfaces. The gas bearing 226 supports the carriage 222 relative to the crossbeam.

[0046] Referring to Figure 3 to Figure 6 Gas bearing 226 is discussed in more detail. (See reference...) Figure 2-4 Other exemplary embodiments may include other types of devices configured to reduce (e.g., eliminate) contact friction between the printhead carriage and the crossbeam. For example, some exemplary embodiments may include various combinations of permanent magnets and / or electromagnets configured to levitate the carriage 222 relative to the crossbeam 116 using magnetic force. Such devices are generally referred to as “magnetic levitation” devices.

[0047] Gas bearings 226 can each be coupled to carriage 222 in a manner that allows each gas bearing 226 to pivot relative to carriage 222. This pivoting capability facilitates the parallel alignment of surfaces 229 with the surface of the crossbeam 116 facing the surfaces 229 of the gas bearings 226. In other words, the pivoting coupling positions the surfaces 229 of the gas bearings 226 flush with the surface of the crossbeam 116. This positioning facilitates the proper operation of the gas bearings 226, i.e., the formation of an air cushion between the gas bearings 226 and the crossbeam 116. In one exemplary embodiment, as... Figure 4 As shown, ball joint 434 is used to connect gas bearing 226 to carriage 222. Therefore, ball joint 231 facilitates the “self-alignment” of gas bearing 226 relative to beam 116. Each gas bearing 226 can be “self-aligned” independently of the others. While ball joint 231 is shown in the embodiment described herein, other articulated assemblies, such as those comprising one or more rotary bearings, are considered to be within the scope of this disclosure.

[0048] In an exemplary embodiment of this disclosure, one or more gas bearings are used to allow one or more bearings to travel along the longitudinal axis A of the bearing. L The movement is connected to the carriage 222. The "longitudinal axis" of the gas bearing used in this document refers to the axis perpendicular to the surface 229 of the gas bearing. For example, as... Figure 2 As shown, the gas bearing 226A is adjusted so that it can move along the longitudinal axis A of the gas bearing 226A. L The adjustable gas bearing 226A is coupled to the carriage 222 in a manner that selectively moves it relative to the carriage 222. In other words, the bearing surfaces 229 of the adjustable gas bearing 226A can be translated, causing them to protrude further or move away from the surface of the printhead carriage 222 where they are mounted. The gas bearing 226A may be referred to as "adjustable gas bearing 226A" or "translational gas bearing 226A". The movement of the adjustable gas bearing 226A along the longitudinal axis of the bearing also causes a change in the orientation of the carriage 222 relative to the crossbeam 116.

[0049] Although Figure 2 The exemplary embodiment shows two regulating gas bearings 226A located at upper and lower positions on one side of the carriage 222; however, other exemplary embodiments may have a single regulating gas bearing or more than two regulating gas bearings 226A. For example, an exemplary embodiment includes four regulating gas bearings at four positions adjacent to the printhead mounting portion 223 on the printhead carriage. Additionally or alternatively, the carriage 222 may include more gas bearings located in addition to those in the above positions. Figure 2 Other locations besides the indicated location, such as, but not limited to, six, eight or more gas bearing locations adjacent to the printhead mounting portion 223, one or more of which may be equipped with an adjustable gas bearing 226A.

[0050] Gas bearing 226C, mounted on carriage 222 opposite to regulating gas bearing 226A, is configured to passively move longitudinally to compensate for the longitudinal movement of regulating gas bearing 226A. That is, because the thickness T of beam 116... Figure 1 The distance between the gas bearing 226A and the gas bearing 226A is nominally constant. Therefore, the change in the longitudinal position of the gas bearing 226A requires the gas bearing 226C, which is opposite to the gas bearing 226A, to move longitudinally so that the distance between the gas bearing 226C and the gas bearing 226A remains constant. The gap between the gas bearings 226A, 226C and the crossbeam 116 allows gas to flow out of the bearing so that the gas bearing 226 can work normally.

[0051] exist Figure 2 In an exemplary embodiment, a gas bearing 226C, which may be referred to as a compensating gas bearing, is connected to the carriage 222 via a spring post 234. The spring post 234 allows longitudinal movement of the compensating gas bearing 226C to compensate for longitudinal movement of the regulating gas bearing 226A. The spring post 234 may be configured with a helical spring, a Belleville spring, a leaf spring, or other mechanical spring constructed of an elastic material (e.g., a metal alloy, polymer, or other material), or may include a gas spring, such as a variable volume pneumatic reservoir, or other types of spring members.

[0052] Only exemplary implementations with θ-z adjustment will be described to explain the various operating principles; other orientation / position adjustments will then be described based on the same general principles. In use, to compensate for changes in the orientation of the carriage 122 and the resulting associated changes in the printhead 124 relative to the substrate 104 (… Figure 1 By changing the direction of the slide 122, the gas bearing 226A can be moved along its longitudinal axis to change the direction of the slide 122, for example, to return the direction of the slide 122 relative to the printed surface of the substrate to the desired θ-z direction, such as in combination with... Figure 3A and Figure 3B Further discussion is needed.

[0053] For reference Figure 3A and 3B It shows the printhead carriage 322 and the printing system (e.g. Figure 1 A schematic plan view of a portion of the crossbeam 316 of the printing system 100 shown. Figure 3A and 3B The view shown is taken from below in a direction perpendicular to and towards the printed surface of the substrate, such as the printed surface 305 of substrate 304, as indicated by the dashed line. Figure 3A In the configuration shown, the gas bearing 326A is in the middle position relative to the carriage 322, and the printhead 324 is in the middle direction relative to the substrate 304.

[0054] Figure 3B It shows something similar to Figure 3A The schematic plan view shown indicates that the regulating gas bearing 326A extends along the longitudinal axis AL relative to the carriage 322 (because the other is located below the visible one). Figure 3A and 3B (Only one of them is shown in the view). Adjusting the extension of the gas bearing 326A causes the carriage to oriented about the z-axis (extension in and out). Figure 3A and 3B The plane of the drawing (axis) rotates clockwise, as shown. Figure 3B As indicated by arrow C. Because changing the direction of the carriage 322 around the z-axis may change the y-axis position of the print head 324 relative to the substrate 304 (i.e., Figure 3A and 3B The vertical position), so the control system of the printing system 100 ( Figure 1 It can also be configured to adjust the y-axis position of the substrate 304 to compensate for changes in the relative y-axis position between the printhead 324 and the substrate 304. Similarly, a change in the z-axis direction of the carriage 322 can cause a change in the position of the carriage 322 along the x-axis (i.e., a change in position along the direction of the beam 316), which can be compensated for by moving the slider 322 along the beam 316.

[0055] although Figure 2-3B Exemplary implementations include two regulating gas bearings (e.g., Figure 2 Of the 226A, one (326A) is in Figure 3B (as shown in the diagram), but other embodiments may optionally have only one regulating gas bearing or two or more regulating gas bearings. For example, in some exemplary embodiments, bearings diagonally opposite the regulating gas bearing (i.e., Figure 3A and 3BThe bearing in the upper left of the diagram extends in a manner similar to that of an adjustable gas bearing. As an additional, non-limiting example, Figure 3A and 3B The gas bearings 326 and 326C can be configured to selectively extend away from the carriage 322 and retract towards the carriage 322 to actively compensate for the extension of the gas bearing 326A, rather than using a method such as Figure 3A and 3B The compensation bearing shown is 326C.

[0056] When the gas bearing 326A and the compensating bearing 326C are moved relative to the carriage to change the orientation of the carriage 322 relative to the crossbeam 316, the rotation direction of the carriage 322 about the z-axis changes, such as... Figure 3B As shown. Gas bearing 326, the ball joints of gas bearing 326A and compensating bearing 326C are adjusted to ensure that the surfaces 329 of gas bearings 326, 326A, and 326C are parallel to the surface of the crossbeam 316, so that gas bearings 326, 326A, and 326C are in... Figure 3B The direction shown maintains a low-friction (e.g., low-friction or frictionless) interface between the crossbeam 316 and the carriage 322. In other words, the ball joint is passively adjusted to ensure that the surfaces 329 of the gas bearings 326, 326A, and 326C remain flush with the surface of the crossbeam 316 to facilitate the formation of an air cushion (e.g., a gas layer) between the surfaces 329 of the gas bearings 326, 326A, and 326C and the surface of the crossbeam 316.

[0057] exist Figure 4 In an exemplary embodiment, the gas bearing 426A is adjusted via a piezoelectric actuator 436 ( Figure 4 It is connected to the printhead carriage 422. The piezoelectric actuator 436 is configured to change shape based on the application of current. Figure 4 In an exemplary embodiment, when current is applied to the piezoelectric actuator 436, the piezoelectric actuator 436 causes the regulating gas bearing 426A to extend from the surface of the carriage 422 to which it is connected. For example, when current is applied, the piezoelectric actuator 436 can change from a first unextended (e.g., retracted) state 438, shown by a solid line, to a second extended state, shown by a dashed line 440. The application of current can be controlled by a control system that controls, for example, the carriage 422 along a crossbeam (e.g., Figure 1-3B The movement of the crossbeam 116, 216, or 316 shown along the x-axis, and the substrate (such as...) Figure 1 The substrate 104 shown or Figure 3A and 3B The substrate 304 shown moves along the y-axis.

[0058] The piezoelectric component can provide the actuator 436 with desired characteristics, including but not limited to, high compressive force, high accuracy, and relatively small movement. The actuator 436 may require the application of high compressive force to overcome the force applied by the gas bearing to the crossbeam (e.g., Figure 1-3B The force exerted on the crossbeam (116, 216, or 316) shown can be approximately several thousand Newtons (N). For example, the force exerted on the crossbeam by the gas bearings can range from approximately 500 N (113 psi) to approximately 1500 N (337 psi). Depending on the number of gas bearings, the area of ​​the bearing surfaces, the weight of the printhead and carriage assembly, and other factors, the force exerted on the crossbeam by the gas bearings may be higher or lower than the exemplary range provided above, for example, less than 500 N or greater than 1500 N.

[0059] The ideal range of rotation about the printhead carriage's z-axis (or applicable x-axis or y-axis) can be less than one radian and can be expressed in microradians. In one exemplary embodiment, the desired range of rotation about a selected axis of the printhead carriage to correct misalignment can be from 0 microradians to 50 microradians, or from 0 microradians to 100 microradians, or other ranges. To facilitate rotation within these ranges, actuators (e.g., Figure 4 The actuator 436 shown will adjust the gas bearing to translate a distance within a micrometer range, for example, from about 0 micrometers to about 100 micrometers, depending on the desired variation in the spacing of the gas bearings (i.e., the distance between them) and the rotation direction of the printhead carriage about the selected axis.

[0060] For example, the spacing of the gas bearings can be approximately 0.5 meters (19.7 inches), the travel range of the gas bearings can be approximately 25 micrometers, and this travel range of the gas bearings allows the carriage to rotate a maximum of approximately 50 microradians about the selected axis. In other exemplary embodiments, the range of directional variation required to correctly orient the printhead carriage about the selected axis and relative to the printing surface of the substrate can be less than or greater than 50 microradians, and correspondingly, the travel range of the gas bearings along their longitudinal axis may vary.

[0061] Actuators other than piezoelectric actuators are considered to be within the scope of this disclosure. For example, in some exemplary embodiments, a regulating gas bearing may be actuated by a hydraulic device, a pneumatic device, an electromechanical device (such as a linear motor), a stepper motor connected to a motion linkage, or any other device configured to move the bearing longitudinally based on electrical or other control signals. As a further non-limiting exemplary embodiment, one or more actuators may include a voice coil type device comprising a magnet and a moving electromagnet, including, for example, a wire coil wound around a spool. Applying a current to the coil generates a magnetic field that interacts with the magnetic field of the magnet, thereby moving the spool. Further discussion of such devices is contained in U.S. Patent Application Publication No. US2018 / 0014411A1, which is incorporated herein by reference.

[0062] exist Figure 4 In an exemplary embodiment, the carriage 422 and the regulating gas bearing 426A may include a mechanical (i.e., “hard”) stop 442 to limit the movement of the regulating gas bearing 426A relative to the carriage, to ensure that when the regulating gas bearing 426A is adjusted to its maximum extension position, the associated printing system (e.g., Figure 1 The printing system 100 shown maintains correct function. Figure 4 In one embodiment, the regulating gas bearing 426A is shown adjacent to the crossbeam 416. Although Figure 4 Mechanical stop 442 has been specifically shown and described, but any exemplary embodiment described herein may include mechanical stop 442.

[0063] exist Figure 4In an exemplary embodiment, the mechanical stop 442 includes one or more annular members 443 located on either side of the shoulder 445 positioned on the actuator. The annular members 443 contact the shoulder 445 to prevent overextension or underextension of the adjusting gas bearing 426A beyond the adjustable range defined by the shoulder 445 and the annular members 443. The adjustable range can be selected based on the amount of extension required to correct the carriage orientation. For example, as described above, in one exemplary embodiment, the adjusting bearing may have an adjustment range of approximately 25 micrometers. Other exemplary embodiments may have a larger adjustment range, such as 50 micrometers, 100 micrometers, or more, or a smaller adjustment range, such as 10 micrometers, 5 micrometers, or less. The mechanical stop 442 limits the actuator's range of motion to a range within which, for a given electrical input, the actuator provides stable, predictable motion. For example, the actuator's range of motion may be limited to a range in which the relationship between the applied current and the actuator's motion is substantially linear. Additionally, when the actuator is not powered, such as when the printing system is powered off for maintenance or when it is not in use, the mechanical stop 442 can keep the position of the actuator and carriage within a defined range.

[0064] In yet another exemplary embodiment, the actuator may include one or more piezoelectric actuators coupled in parallel with other devices between the regulating gas bearing and the carriage, said other devices being configured to support at least a portion of a load applied between the regulating gas bearing and the carriage. Such devices may include, for example, resiliently biased members, such as mechanical or pneumatic springs. For example, see reference... Figure 5 The diagram shows a schematic side view of the regulating gas bearing 526A and the carriage 522. A spring 546 (such as a coil spring) is connected between the regulating gas bearing 526A and the carriage 522 and mounted in parallel with an actuator (such as a piezoelectric actuator) 536. The spring 546 can support a portion of the load applied between the regulating gas bearing 526A and the carriage 522, while the piezoelectric actuator 536 precisely positions the carriage 522 relative to the regulating gas bearing 526A in the manner described above. For example, this load could be a printhead supported by the carriage 522. Figure 5 The applied force is generated by at least a portion of the weight of the carriage 522 (not shown in the figure) and the weight of the carriage 522.

[0065] For reference Figure 6 It shows a similar combination Figure 5 The configuration is described. Figure 6In this configuration, a pneumatic spring 647 (e.g., including a piston-cylinder assembly) replaces the coil spring 546 and is positioned parallel to the piezoelectric actuator 636 between the regulating gas bearing 626A and the carriage 622. The pneumatic spring 647 supports a portion of the load applied between the regulating gas bearing 626A and the carriage 622, while the piezoelectric actuator 636 precisely positions the carriage 622 relative to the regulating gas bearing 626A.

[0066] During use, the printhead carriage (e.g., printhead carriage 122, 222, 322, or 422) can be driven by a linear motor system along the crossbeam (e.g., ... Figure 1 –The crossbeam 116, 316, or 416 shown in –3B moves, and the linear motor system includes a stator (not shown) connected to the carriage 422 and a series of permanent magnets or electromagnets (not shown) embedded in or fixed to the crossbeam. Extension of the regulating gas bearing 426A beyond a certain extent may potentially affect the stator alignment relative to the magnets and could cause the stator to strike the magnets or the crossbeam. Mechanical stop 442 prevents the regulating gas bearing 426A from extending beyond a specific distance at which the linear motor maintains proper function and the carriage 422 does not strike the crossbeam. Although in Figure 4 The embodiments specifically illustrate mechanical stops that can be used with any other embodiment shown in this disclosure, or in combination with other embodiments.

[0067] In some exemplary embodiments, the printing system may include a system for correcting deviations from the intended transport path of the substrate transport system, such as substrate support system 102. Figure 1 The correction system can be substantially as described in U.S. Patent Application Publication No. 2018 / 0014411A1, or U.S. Patent No. US9505245, published November 29, 2016, the entire contents of which are incorporated herein by reference. Such a system may include a transport system, such as a substrate holder, configured to guide components, such as substrates, along a transport path to aid in manufacturing. In a typical implementation, the transport path can be on the order of meters, while the required positioning can be on the order of micrometers or finer (e.g., nanometers or finer). To aid in precise positioning, one or more sensors are used to detect deviations between the component (e.g., substrate) and the crossbeam in one or more dimensions. The deviations detected by the one or more sensors are then used to derive a position correction signal, which is fed to one or more transducers and used to compensate for the deviations. Despite the fine mechanical errors associated with the transport path, the assembly is allowed to track the optical path. In an exemplary embodiment, one or more sensors provide feedback that ensures the transducers are always “zeroed” for position and / or rotational errors.

[0068] In exemplary embodiments of this disclosure, one or more aspects of the path-corrected transport system can be used in conjunction with an adjustable printhead carriage (e.g., printhead carriages 122, 222, 322, 422, 522, 622, or 1222). The combination of a printhead carriage configured to provide rotational adjustment about various axes of rotation and positional adjustment along various axes with path correction provided by embodiments disclosed in U.S. Patent Application Publication No. US2018 / 0014411A1 or U.S. Patent 9505245 can provide high-precision printhead and substrate positioning to ensure accurate, precise, and repeatable printing results. Furthermore, the rotational and positional adjustments provided by the printhead carriage can reduce or eliminate the need for rotational adjustment of the substrate via the transport system, thereby allowing a transport system with fewer components to achieve adjustability and less associated complexity to provide full adjustment of the substrate and printhead as needed to correct for transport path errors (deviations from the expected transport path) and rotational or positional errors (e.g., θ-z errors or other deviations from the expected rotational alignment or printhead position) to provide accurate printing results.

[0069] Embodiments of this disclosure may include a control system configured to rotate or translate the carriage (e.g., carriages 122, 222, 322, 422, 522, 622, or 1222) as needed to correct for rotational or positional errors caused by deviations in the straightness and / or flatness of the crossbeam 116 or components associated with the substrate support system 102. Such a control system may include one or more sensors configured to determine the actual position and orientation of the carriage and substrate transport system, and one or more processors operatively coupled to said one or more sensors. In exemplary embodiments of this disclosure, said one or more sensors may include one or more components, such as encoders, interferometers (e.g., laser interferometers), other optical measuring devices (e.g., cameras), or other devices. The control system may be an integrated control system that controls both the printhead carriage and the transport system, or it may include two substantially discrete control systems that independently control each of the substrate transport system and the printhead carriage.

[0070] In an exemplary embodiment, based on information about the actual position and orientation of the printhead carriage as it translates along the crossbeam in the x-axis direction, the desired position or direction of rotation of the printhead carriage relative to a specific axis of rotation is determined, or the required amount of adjustment of the carriage's position and / or orientation to compensate for misalignment is determined. In one exemplary embodiment, a measuring device on the printhead (e.g., Figure 1 , 3AThe printheads 124 and 324 shown in 3B are used to determine any misalignment or positional error that occurs as the printhead carriage moves along the crossbeam. For example, one or more of the aforementioned camera, interferometer (e.g., laser interferometer), or other measuring devices can be used to collect information about the orientation and position of the printhead as the carriage moves along the crossbeam. This data on orientation and position can be provided to a control system that controls the position of the printhead carriage (printhead carriages 122, 222, 322, 422, 522, 622, or 1222), the substrate (e.g., ...), and the position of the printhead carriage. Figure 1 , 3A The y-position of the substrates 104 and 304 shown in Figure 3B and the direction of rotation of the printhead carriage about one or more rotation axes (and therefore the direction of rotation of the printhead carried by the printhead carriage) (e.g., the θ-z direction of the printhead carriage). The control system can also perform other control functions, such as loading and unloading the substrate, controlling the deposition of organic material through the printhead, and other functions of the printing system 100.

[0071] Additionally, the center of rotation of the printhead about any of the x, y, or z axes may deviate from the center of the printhead; therefore, adjusting the direction of rotation of the carriage about one axis may also cause the printhead to move in the x, y, or z direction. The control system can be programmed or otherwise configured to compensate for these movements and to move the carriage or substrate by the appropriate amount based on the rotational adjustment about the x, y, and / or z axes.

[0072] In some exemplary embodiments, the control system can operate on a "real-time" basis, wherein data regarding the actual position and / or orientation of the substrate carried by the transport system or printhead carriage is collected and processed as the carriage moves along crossbeams 116, 316, 416, 1216. The control system can then process the real-time data and adjust the position and / or orientation of the transport system or printhead carriage to address inaccuracies in the orientation or position of the transport system or carriage during printing operations.

[0073] As an alternative to a "real-time" control configuration, in various exemplary embodiments, the control system can record the required carriage movement to compensate for any inaccuracies present in the crossbeam along which the carriage moves during the initial calibration. As the carriage crosses the crossbeam, the required correction amount for the carriage orientation can be calculated based on measurements taken by one or more sensors (e.g., interferometers or other measuring devices). The measurements can be collected in a table or as a mapped correction value associated with the carriage position along the crossbeam. Thus, each correction value is associated with a specific position of the carriage, and the collection of correction values ​​indicates a specific error present in the crossbeam, such as variations in the flatness or thickness of the crossbeam. Therefore, the table or mapping of correction values ​​is associated with a specific crossbeam used in the printing system performing the calibration. The correction values ​​can be stored in an electronic memory operatively coupled to a processor of the control system, and the control system applies the correction value associated with each position of the carriage on the crossbeam or transport system along the transport path without remeasuring the position and / or orientation errors of the carriage and transport system each time the carriage crosses the crossbeam and the transport system moves along the transport path.

[0074] For reference Figure 7 The diagram illustrates a block diagram of a control system 750 for controlling a printing system according to an exemplary embodiment of the present disclosure. The control system 750 includes at least one sensor device 752 configured to generate a representation of the printhead (e.g., ...). Figure 1 , 3A The output signal of the orientation and / or position of the printheads 124, 324, 1224 (in 3B and 12-15) relative to the printing surface of the substrate, on which the printheads are configured to deposit material, such as ink. The sensor device 752 may include one or more sensors, such as those described herein and / or interferometers, encoders, or other devices familiar to those skilled in the art. In one embodiment, the sensor device 752 includes one or more laser interferometers.

[0075] Sensor device 752 is operatively coupled to controller 754, such as a computer system, which includes, for example, a processor and electronic storage medium. Controller 754 receives information from sensor device 752 regarding the rotational direction and / or position of the printhead relative to the printing surface. Additionally, in some embodiments, controller 754 may receive information from other devices associated with the printing system, such as being configured to generate information related to the printhead in the x, y, and z directions (e.g., along the aforementioned...). Figure 1-4 Other sensors that provide information about the rotational direction and position of the x, y, and z axes (discussed in the associated exemplary embodiments). Additionally or alternatively, the controller 754 may receive information from other means and systems of the printing system, such as systems configured to support and / or transport the substrate (e.g., Figure 1The substrate support system 102 shown, and the system configured to move the printhead (e.g., Figure 1 The motion system 108 shown. The controller 754 can receive inputs related to the operation of the printing system, such as the position of the print head and substrate, the operating status of the printing system, information related to other components of the printing system (e.g., gas hood), or other inputs.

[0076] The controller 754 can be operatively coupled to various components of the printing system, such as the substrate support system (e.g., Figure 1 102 in the middle) and motion control system (e.g., Figure 1 (108 in the diagram), or other components of the printer. Based on input from sensor device 752 and any other sensors or input devices operatively coupled to controller 754, controller 754 can generate output signals to control the printing system. For example, controller 754 can be configured to send output signals to one or more control devices 756 of the printing system. Control devices 756 may include, for example, controllable components associated with components of the printing system (such as motors, servo motors, linear motors, or other actuators).

[0077] exist Figure 5 In an exemplary embodiment, controller 754 sends an output signal to control device 756, which includes, for example, one or more actuators (e.g., Figure 4 The piezoelectric actuator 436 shown is configured to change position and / or shape based on an applied current. In this way, the output signal from the controller 754 can be used to control the actuation state of the actuator 436 and the printhead (e.g., Figure 1 and 3A The corresponding orientation of the printheads 124, 324 in / 3B. Furthermore, in exemplary embodiments, the controller 754 can provide additional outputs controlling the operating state of the printing system, for example, through the control substrate support system, motion control system, or other operational aspects of the printing system.

[0078] In some exemplary embodiments, the control device 756 may optionally include means configured to provide feedback to the controller 754. For example, in one exemplary embodiment, the control device 756 is a piezoelectric actuator with an associated encoder device 757 configured to provide feedback to the controller 754 regarding the actual position of the control device 756. The encoder device 757 may be an optical encoder, a magnetic encoder, or any other means configured to generate signals based on the position or movement of the control device 756. If, based on the received feedback, the control device 756 has reached the target position, the controller 754 holds the control device in the target position. Once feedback from the encoder device 757 indicates that the control device 756 has reached the target position, the controller 754 stops moving the control device 756.

[0079] For reference Figure 8 Flowchart 860 illustrates the workflow for adjusting the position and / or orientation of the printhead carriage along the axis. Throughout the text, the term "position" refers to the translational position along the axis, and the term "orientation" refers to the direction of rotation about the axis. Figure 8 The exemplary implementation illustrates one example of a control method that uses real-time input regarding the actual position and / or orientation of the carriage and adjusts the position and / or orientation of the carriage based on said real-time input. In 862, the workflow includes sensing information relating to the direction of rotation of the printhead about an axis perpendicular to the printing surface on which material will be deposited. The printhead may be carried by a printhead carriage movably mounted on a crossbeam extending through a substrate support system. Sensing information relating to the sensing orientation of the printhead may be provided to a controller, such as controller 754 in various exemplary embodiments. Figure 7 ).

[0080] In 864, for example based on sensed information, one or both of the position of the printhead carriage along the axis and the direction of rotation about the axis are adjusted. As described above, in an exemplary embodiment, the adjustment can be made by one or more actuators, such as actuator 436 ( Figure 4 This is achieved by the actuator changing its size, shape, position, or other characteristics to adjust the orientation of the printhead relative to the substrate about an axis perpendicular to the printing surface of the substrate. For example, as described above... Figure 1-4 The actuators discussed can be one or more non-contact bearings, such as gas bearings 226, 326, and 426. Figure 2 , 3A 3B and 4) move along their respective longitudinal axes to change the orientation of the printhead. In various exemplary embodiments, such actuators can be, for example, controller 754 ( Figure 7This is controlled by a controller such as a sensor. For example, a controller that receives sensed information can be used to output a signal to control the actuator to adjust the printhead carriage.

[0081] At point 866, one or both of the actual orientation of the printhead carriage about the axis and its actual position along the axis are sensed, and further control or adjustment can be made based on the actual orientation and position if needed, or the orientation and position can be verified and adjustment stopped. For example, in an exemplary embodiment, the controller receives data from the encoder (e.g., Figure 7 The encoder device 758 or another measuring device (e.g., sensor device 752) is used. Figure 7 One or both of the following signals are received: An encoder or other measuring device can sense one or both of the actuator position, bearing position, or carriage position, and provide the sensed information to the controller as a signal indicating the actual position of the sensed component. The controller evaluates the received signal based on, for example, stored geometric relationships that correlate the positions of various components (e.g., actuators and / or bearings) with the actual orientation and / or position of the carriage. If, according to the information received by the controller, the carriage is not in the desired orientation and / or position, the controller can further adjust the orientation and / or position of the carriage until the signal received from the encoder or sensor indicates that the orientation and / or position is correct. As described above... Figure 3A and 3B As discussed, for example, correction of the carriage in the θ-z direction can cause positional changes of the printhead relative to the substrate in the x and y directions. The controller can be configured to adjust the x and y positions of the printhead as needed based on changes in the printhead's orientation about the z-axis. Similarly, changes in rotational direction about the x or y axis can cause translational positional changes along the x, y, and z axes, and the controller can be programmed to correct for such positional changes based on information from one or more sensors.

[0082] As a combination of the preceding Figure 8 An alternative to the described real-time control method, in some exemplary embodiments, is that the control system can be programmed with information from an initial calibration process, and the controller uses the information obtained during the initial calibration to control the carriage orientation during subsequent printing operations. In one embodiment of this arrangement, the measuring device for determining the direction of the carriage as it moves along the crossbeam is only temporarily attached to a component of the printing system for calibration, and can subsequently be removed from the printing system once the calibration process is complete. Therefore, since the measuring system does not need to be permanently mounted on the printing system, this arrangement can be used to reduce the cost and overall complexity of the printing system.

[0083] For reference Figure 9Another exemplary implementation of workflow 970 includes an initial calibration process using one or more measuring devices, after which the one or more measuring components used for the initial calibration process are not required for subsequent printing operations. For example, in 972, workflow 970 includes sensing information relating to the rotational direction of the printhead and / or the position of the printhead relative to the printing surface on which material is deposited. Such sensing can be accomplished by measuring devices such as interferometers, cameras, and other measuring devices as described above. In various exemplary embodiments, measurement information relating to the orientation and position of the printhead from the measuring devices is received at the controller as the printhead carriage moves along the travel path (e.g., along beams 116, 316, 416). In 974, as the printhead moves along the travel path, the orientation and / or position of the printhead is adjusted. For example, in various exemplary embodiments, the controller sends signals to one or more actuators to adjust the rotational direction or position of the carriage and printhead until information from the measuring devices indicates that the orientation and / or position of the printhead has reached the desired orientation. Optionally, a sensor, such as an encoder coupled to the actuator, provides a signal to the controller containing information about the actual position of the actuator relative to the carriage (e.g., linear extension). Another sensor may provide the controller with information about the position of the carriage and printhead along the travel path (e.g., along the crossbeam). Additional adjustments to the position and / or orientation of the printhead may be made as needed, based on changes in the direction or position of the printhead caused by adjustments to one or more actuators.

[0084] In 976, information relating to the direction of rotation of the printhead and the position of the printhead along the travel path, as well as the direction perpendicular to the travel path, is stored to create a set of correction values ​​corresponding to the printhead position along the travel path. For example, in various exemplary embodiments, the controller associates information about the position of one or more actuators with the position of the carriage along the crossbeam to generate a set of actuator position values ​​associated with the carriage position along the crossbeam. This set of information may optionally include desired x-, y-, and z-direction correction values ​​for a given carriage position along the crossbeam to compensate for positional variations due to carriage rotation about a given axis. The set of associated values ​​may be referred to as a table, list, map, etc., and may be stored on electronic memory operatively coupled to the processor. Electronic memory may include, but is not limited to, random access memory (RAM), read-only memory (ROM), electronic memory such as a disk drive, flash memory, or any other type of electronic storage medium or device.

[0085] When the printing system is used after the initial calibration procedure, as the carriage moves along the crossbeam, the controller controls one or more actuators on the carriage based on the extension value of the actuators associated with the carriage position, thereby adjusting the orientation and / or position of the carriage and printhead according to the position of the carriage along the crossbeam. For example, now refer to Figure 10 The diagram illustrates workflow 1080. At 1082, information relating to the position of the printhead along the travel path is sensed. For example, in various exemplary embodiments, during printing operations, the controller receives information about the position of the carriage along the crossbeam. At 1084, the rotation direction and / or position of the printhead is adjusted based on stored correction values ​​corresponding to the printhead's position along the travel path. For example, in various exemplary embodiments, the controller may base its adjustments on values ​​stored in electronic memory, such as those combined with... Figure 9 The system uses stored data from the actions 976 in the workflow to adjust the carriage's orientation or position. In this way, the control system can correct orientation and position errors based on initial calibration without relying on real-time measurements, reducing the need to integrate measurement sensors and systems with the printing system and thus lowering the complexity of the printing system.

[0086] Figures 12 to 15 The schematic diagram illustrates the use of one or more actuators on the carriage to adjust the carriage about the x-axis and y-axis (in Figure 1 The direction (in the coordinate system). Although in the above exemplary embodiment, only two of the gas bearings 226 are adjustable gas bearings and configured to provide adjustment about the z-axis, in other exemplary embodiments, the system may include more than two adjustable gas bearings to facilitate adjustment about an additional axis and / or position along an additional axis. In some exemplary embodiments, each gas bearing may be attached to an actuator and thus may be an adjustable gas bearing. The number of adjustable gas bearings may be based on the desired number of discrete adjustments, with more gas bearings having actuators as the number of adjustments increases.

[0087] For reference Figure 12 It shows a cross-sectional view of the beam 1216, carriage 1222, and printhead 1224 taken in a plane perpendicular to the length of the beam 1216. Figure 12 In the direction of the drawing, the x-axis extends both inside and outside the plane of the drawing. To rotate the carriage 1222 about the x-axis, actuators associated with adjustable bearings 1286, 1287 are actuated to increase the distance between the carriage 1222 and the surfaces of each adjustable bearing 1286, 1287 facing the crossbeam 1216. An actuator associated with adjustable bearing 1288 is actuated to decrease the distance between the surfaces of the carriage 1222 and the adjustable bearing 1288 facing the crossbeam 1216. As a result, the carriage 1222 and the associated printhead 1224 rotate about the x-axis along... Figure 12 The view shows a counter-clockwise rotation as indicated by arrow R. If it is desired that the carriage 1222 and printhead 1224 rotate clockwise about the x-axis, the actuator associated with the adjustable bearings 1286, 1287 is actuated to decrease the distance between the carriage 1222 and the surfaces of the adjustable bearings 1286, 1287 facing the crossbeam 1216, and the adjustable bearing 1288 is actuated to increase the distance between the surfaces of the carriage 1222 and the adjustable bearing 1288 facing the crossbeam 1216. In this way, the adjustable bearing 1288 can be used to compensate for errors in the x-axis direction of the carriage 1222 as it moves along the crossbeam 1216. Although in Figure 12 In exemplary embodiments, each of bearings 1286, 1287, and 1288 includes an actuator; however, one or more bearings may optionally be fixed or passively movable (e.g., with a spring seat). For example, in one exemplary embodiment, bearing 1286 may be passively movable to passively compensate for the actuation of adjustable bearings 1287 and 1288. As another embodiment, bearing 1288 may be fixed relative to carriage 1222, and bearing 1286 may be passively or actively adjusted to compensate for the movement of bearing 1287 when adjustable bearing 1287 is actuated. Similarly, bearing 1287 may be fixed, while one or both of bearings 1286 and 1288 may include actuators.

[0088] For reference Figure 13 It shows a method for achieving rotation about the y-axis. Figure 13 The view is from Figure 12 The view is rotated 90 degrees around the z-axis and is a section taken in the plane containing the longitudinal axis of the beam. The y-axis extends in and out. Figure 13 The plane of the diagram. In Figure 13 In the view, two adjusting bearings 1390 and 1392 are located on top of the carriage 1222. To allow the carriage 1222 and the printhead 1224 to rotate counterclockwise about the y-axis, adjusting bearing 1390 extends relative to the carriage 1222, while adjusting bearing 1392 retracts relative to the carriage 1222, causing the carriage 1222 to rotate relative to the crossbeam 1216 as shown. Figure 13 The rotation is indicated by arrow R. Clockwise rotation about the y-axis can be achieved by extending the adjusting bearing 1392 and retracting the adjusting bearing 1390 relative to the carriage 1222, thus reversing the direction of rotation R. Although in Figure 13In the exemplary embodiment, both adjusting bearings 1390 and 1392 are shown and described as being connected to an actuator; however, in other exemplary embodiments, only one of adjusting bearings 1390 and 1392 includes an actuator, and a fixed bearing is used instead of the other adjusting bearings 1390 and 1392. By extending or retracting said one adjusting bearing, rotation about the y-axis can be achieved in either direction, while the fixed bearing maintains a fixed distance from the carriage 1222. This compensates for errors in the y-axis direction caused by the movement of the carriage 1222 along the crossbeam 1216.

[0089] For reference Figure 14 It shows something similar to Figure 13 The view shows the cross-sections of the beam 1216 and the carriage 1222 cut in a plane in which the longitudinal axis of the beam 1216 lies. To adjust the position of the carriage 1222 and the printhead 1224 relative to the beam 1216 in the z-direction, adjusting bearings 1390 and 1392 are simultaneously extended or retracted to raise or lower them relative to the beam 1216 as needed. Figure 14 (in the direction) carriage 1222, to correct the inaccuracy at the z-position that occurs when carriage 1222 moves along crossbeam 1216. Although Figure 14 Two adjusting bearings 1390 and 1392 are shown, but embodiments having a single adjusting bearing or more than two adjusting bearings centrally positioned on the carriage 122 are also within the scope of this disclosure.

[0090] For reference Figure 15 It shows something similar to Figure 12 The view shows the cross-section of the beam 1216 cut in a plane perpendicular to the longitudinal axis of the beam 1216. To adjust the position of the carriage 1222 in the y-direction, adjusting bearings 1594 and 1596 are extended while adjusting bearing 1598 is retracted, and the carriage 1222 moves in the y-direction. To reverse the movement of the carriage 1222 in the y-direction, adjusting bearings 1594 and 1596 are retracted while adjusting bearing 1598 is extended. In this way, the positional error of the carriage 1222 and the printhead 1224 in the y-direction can be compensated.

[0091] Various exemplary embodiments of this disclosure provide directional changes of the carriage 1222 and printhead 1224 about any one or a combination of the x-, y-, and z- axes, as well as translational movements of the carriage 1222 and printhead 1224 along any or both directions perpendicular to the direction of movement of the carriage 1222 along the crossbeam 1216 (i.e., the y-axis and z-axis depicted in the figures). These can be dynamically adjusted based on real-time feedback, such as in combination with... Figure 8 The workflow described herein. Alternatively, adjustments can be made based on data collected and recorded during the calibration process, such as in conjunction with... Figure 9and Figure 10 The workflow is described.

[0092] Devices manufactured using embodiments of the apparatus, systems, and methods disclosed herein may include, for example, but not limited to, electronic displays or display components, printed circuit boards, or other electronic components. Such components can be used in, for example, handheld electronic devices, television or computer displays, or other electronic devices incorporating display technologies.

[0093] It should be understood that the specific embodiments and implementations set forth herein are non-limiting, and modifications may be made to the structure, dimensions, materials, and methods without departing from the scope of this teaching. Other embodiments of the invention disclosed herein will be apparent to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. The specification and embodiments are intended to be illustrative only, and the appended claims shall enjoy their full width, including equivalents, in accordance with applicable law.

Claims

1. A method of controlling a printing system having a printhead carriage supporting a printhead mounted to translate along a beam, the method comprising: sensing one or more of a rotational error of the printhead and a positional error of the printhead; and dynamically adjusting a position of one or more bearings in accordance with one or more of the sensed rotational error and the positional error, wherein dynamically adjusting the position of the one or more bearings will adjust one or more of a rotation of the printhead and a position of the printhead, wherein the one or more bearings are magnetic levitation bearings.

2. The method of claim 1, wherein adjusting the position of the one or more bearings comprises actuating an actuator.

3. The method of claim 2, wherein the actuator comprises a piezoelectric element, a pneumatic actuator, a hydraulic actuator, or an electromechanical actuator.

4. The method of claim 1, wherein dynamically adjusting the position of the one or more bearings comprises correcting a position or a rotational orientation of the printhead.

5. The method of claim 1, wherein the rotational error, the positional error, or both are sensed using a laser interferometer.

6. The method of claim 1, further comprising sensing a position of the printhead carriage along the beam.

7. The method of claim 1, wherein the position of the one or more bearings is adjusted during printing on a print surface while the printhead is moving along the beam.

8. The method of claim 1, wherein dynamically adjusting the position of the one or more bearings comprises actuating the one or more bearings along a longitudinal axis of the bearings.

9. A method of controlling a printing system having a printhead carriage supporting a printhead mounted to translate along a beam extending in an x-axis direction of an x, y, z Cartesian coordinate system, the method comprising: sensing information related to a position of the printhead along a travel path extending in the x-axis direction; sensing information related to one or more of a rotational orientation of the printhead about the x, y, and z axes and a position of the printhead along the y and z axes; based on the sensed position, dynamically adjusting one or both of the rotational orientation and the position of the printhead by operating an actuator coupled to one or more bearings of the printhead carriage that carries the printhead, wherein the one or more bearings are magnetic levitation bearings; and storing information related to the position of the one or more bearings of the printhead carriage in relation to a corresponding position of the printhead carriage along the travel path.

10. The method of claim 9, wherein storing information related to the position of the one or more bearings of the printhead carriage comprises receiving information related to the position of the one or more bearings of the printhead carriage from an encoder.

11. The method of claim 9, wherein sensing information related to one or more of the rotational orientation of the printhead and the position of the printhead comprises sensing the information using a laser interferometer.

12. The method of claim 9, wherein sensing information related to one or more of the rotational orientation of the printhead and the position of the printhead comprises imaging calibration marks of a calibration device with a camera. ​ 13. The method of claim 1 or 9, wherein the one or more bearings minimize contact between the bearings and the cross beam.

14. The method of claim 9, further comprising determining an error in a position or orientation of a mark on a substrate.

15. The method of claim 9, wherein the rotational orientation, the position, or both are sensed using a laser interferometer.

16. A printing system comprising: a substrate support system configured to support a substrate having a surface to be printed, wherein the substrate support system is configured to hold the surface to be printed in an x-y plane substantially perpendicular to a z-axis of an x-axis, y-axis, z-axis Cartesian coordinate system, a cross beam extending in an x-axis direction across the substrate support system; and a print head carriage movably coupled to the cross beam for movement in the x-axis direction, the print head carriage comprising one or more bearings, wherein the one or more bearings are magnetic levitation bearings.

17. The printing system of claim 16, wherein a bearing surface of at least one of the magnetic levitation bearings faces the cross beam.

18. The printing system of claim 17, wherein at least one of the one or more bearings is adjustable along a longitudinal axis of the bearing, the longitudinal axis being perpendicular to the bearing surface.

19. The printing system of claim 17, further comprising at least one ball joint coupling one of the one or more bearings to the print head carriage.

20. The printing system of claim 16, further comprising an actuation mechanism coupling one of the one or more bearings to the print head carriage.

21. The printing system of claim 20, wherein the actuation mechanism comprises a piezoelectric element.

22. The printing system of claim 20, further comprising a resilient biasing member coupled between the one or more bearings and the print head carriage.

23. The printing system of claim 22, wherein the resilient biasing member is coupled between the one or more bearings and the print head carriage in parallel with the actuation mechanism.

24. The printing system of claim 22, wherein the resilient biasing member comprises a coil spring.

25. The printing system of claim 22, wherein the resilient biasing member comprises a pneumatic piston cylinder device.

26. The printing system of claim 16, wherein information about an orientation or a position of the print head, or both, is sensed using a laser interferometer as the print head carriage moves along the cross beam.

27. The printing system of claim 16, wherein the one or more bearings minimize contact between the bearings and the cross beam.

28. A method of controlling a printing system having a print head carriage supporting a print head mounted for translation along a cross beam extending in an x-axis direction of an x-axis, y-axis, z-axis Cartesian coordinate system, the method comprising: sensing one or more of a rotational orientation of the print head about the x-axis, the y-axis, or the z-axis, and a position of the print head along the y-axis or the z-axis; and ​ ​ adjusting a position of one or more bearings based on one or more of the sensed rotational direction and position, wherein adjusting the position of the one or more bearings will adjust one or more of the rotational direction of the printhead and the position of the printhead, wherein the one or more bearings are gas bearings.

29. The method of claim 28, wherein adjusting the position of the one or more bearings comprises actuating an actuator.

30. The method of claim 28, wherein adjusting the position of the one or more bearings comprises adjusting the position of the one or more bearings until the printhead carriage reaches one or both of a target rotational direction and a target position.

31. The method of claim 30, further comprising sensing information related to one or both of a rotational direction of the printhead and a position of the printhead to confirm the printhead in one or both of the target rotational direction and the target position.

32. The method of claim 30, further comprising sensing information related to the position of the one or more bearings when the printhead carriage reaches one or both of the target rotational direction and the target position.

33. The method of claim 28, further comprising sensing a position of the printhead carriage along a cross beam extending in an x-axis direction.

34. The method of claim 28, wherein the position of the one or more bearings is adjusted during printing on a print plane in an x-y plane while the printhead is moving along the cross beam extending in the x-axis direction.

35. The method of claim 28, wherein adjusting the position of the one or more bearings comprises actuating the one or more bearings along a longitudinal axis of the bearings.

36. The method of claim 28, wherein the rotational direction, the position, or both are sensed using a laser interferometer.

37. A method of controlling a printing system having a printhead carriage supporting a printhead mounted for translation along a cross beam extending in an x-axis direction of an x-axis, y-axis, z-axis Cartesian coordinate system, the method comprising: sensing information related to a position of the printhead along a travel path extending in the x-axis direction; sensing information related to one or more of a rotational direction of the printhead about the x, y, and z-axes and a position of the printhead along the y-axis and z-axes; adjusting one or both of the rotational direction of the printhead and the position of the printhead by operating an actuator coupled to one or more bearings of the printhead carriage carrying the printhead based on the sensed position, wherein the one or more bearings are gas bearings; and storing information related to the position of the one or more bearings of the printhead carriage in relation to a corresponding position of the printhead carriage along the travel path.

38. The method of claim 37, wherein storing information related to the position of the one or more bearings of the printhead carriage comprises receiving information related to the position of the one or more bearings of the printhead carriage from an encoder.

39. The method of claim 37, wherein sensing information related to one or more of a rotational direction of the printhead and a position of the printhead comprises sensing the information using a laser interferometer.

40. The method of claim 37, wherein sensing information relating to one or more of the rotation direction and position of the printhead comprises imaging calibration marks of the calibration device with a camera.

41. The method of claim 28 or 37, wherein the one or more bearings minimize contact between the bearing and the crossbeam.

42. The method of claim 37, wherein the rotation direction, the position, or both are sensed using a laser interferometer.

43. A printing system, comprising: A substrate support system configured to support a substrate having a surface to be printed, wherein the substrate support system is configured to hold the surface to be printed in the xy plane, which is substantially perpendicular to the z-axis of a Cartesian coordinate system. A crossbeam extending through the substrate support system in the x-axis direction, and A printhead carriage movably coupled to the crossbeam for movement in the x-axis direction, the printhead carriage including one or more bearings, wherein the one or more bearings are gas bearings. This involves moving one or more bearings along the longitudinal axis of the bearings, at least one of which is connected to an actuator that can be selectively adjusted to adjust one or more of the rotational directions of the printhead carriage about the x-axis, y-axis, and z-axis, and the position of the printhead carriage in the y-axis direction and the z-axis direction.

44. The printing system of claim 43, wherein the bearing surface of at least one of the gas bearings faces the crossbeam.

45. The printing system of claim 44, wherein at least one of the one or more bearings is adjustable along the longitudinal axis of the bearing, the longitudinal axis being perpendicular to the bearing surface.

46. ​​The printing system of claim 44, further comprising at least one ball joint connecting one of the one or more bearings to the printhead carriage.

47. The printing system of claim 43, further comprising an actuation mechanism that connects one of the one or more bearings to the printhead carriage.

48. The printing system of claim 47, wherein the actuation mechanism comprises a piezoelectric element.

49. The printing system of claim 47, further comprising a resilient biasing member connected between the one or more bearings and the printhead carriage.

50. The printing system of claim 49, wherein the resilient biasing member is connected in parallel with the actuation mechanism between the one or more bearings and the printhead carriage.

51. The printing system of claim 49, wherein the resilient biasing member comprises a helical spring.

52. The printing system of claim 49, wherein the resilient biasing member comprises a pneumatic piston cylinder device.

53. The printing system of claim 43, wherein the rotation direction, the position, or both are sensed using a laser interferometer.

54. A printing system, comprising: A substrate support system configured to support a substrate having a surface to be printed, wherein the substrate support system is configured to hold the surface to be printed in the xy plane, which is substantially perpendicular to the z-axis of a Cartesian coordinate system. A crossbeam extending through the substrate support system in the x-axis direction; as well as A printhead carriage movably coupled to the crossbeam for movement in the x-axis direction, the printhead carriage including one or more bearings, wherein the one or more bearings are gas bearings.

55. The printing system of claim 54, wherein the bearing surface of at least one of the gas bearings faces the crossbeam.

56. The printing system of claim 55, wherein at least one of the one or more bearings is adjustable along the longitudinal axis of the bearing, the longitudinal axis being perpendicular to the bearing surface.

57. The printing system of claim 54, further comprising at least one ball joint connecting one of the one or more bearings to the printhead carriage.

58. The printing system of claim 54, further comprising an actuation mechanism that connects one of the one or more bearings to the printhead carriage.

59. The printing system of claim 58, wherein the actuation mechanism comprises a piezoelectric element.

60. The printing system of claim 58, further comprising a resilient biasing member connected between the one or more bearings and the printhead carriage.

61. The printing system of claim 60, wherein the resilient biasing member is connected in parallel with the actuation mechanism between the one or more bearings and the printhead carriage.

62. The printing system of claim 60, wherein the resilient biasing member comprises a helical spring.

63. The printing system of claim 60, wherein the resilient biasing member comprises a pneumatic piston cylinder device.

64. The printing system of claim 54, wherein a laser interferometer is used to sense information about the orientation or position of the print head, or both, as the print head carriage moves along the crossbeam.

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