Inkjet Printer Calibration

Abstract

In a high-precision manufacturing method, precise positioning is required to accurately drop the material onto the workpiece. 【Solution means】 The manufacturing system includes a dispenser unit movably coupled to a support portion and having a position sensor and a reference detector, a test unit including a surface that receives the material from the dispenser unit and an imaging device that images the material on the surface, a position reference portion mounted on a stationary component of the manufacturing system, and a control unit. The control unit controls the dispenser unit and the reference detector to detect the position reference portion, calibrates the position of the dispenser unit based on the detection of the position reference portion, controls the test unit to image the material on the surface, controls the dispenser unit and the reference detector to detect the characteristics of the material on the surface, compares the image of the material captured by the test unit with the characteristics of the material detected by the reference detector, and calibrates the test unit based on the comparison.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 268,357, filed on February 22, 2022, the entire content of which is incorporated herein by reference.

Background Art

[0002] In high - precision manufacturing methods, in order to precisely drop materials onto a workpiece, a positioning device that detects the positions of components that require precise positioning is used. The positioning device needs to be calibrated. When the manufacturing process of a single workpiece is complex and multiple positioning devices are used, it is necessary to frequently calibrate these positioning devices with respect to a single position reference, such as the global coordinate system of a manufacturing system. The manufacturing method often includes dropping materials onto the workpiece, and such discharges may be performed by multiple dispensers. When it is necessary to precisely position all dispensers and precisely discharge materials, the operations of all dispensers must be accurately calibrated with respect to a single position reference. Examples of such manufacturing systems include devices regarded as printers, including industrial - scale inkjet printers, coater, 3D printers, and other droplet or liquid - flow discharge systems. There is a need for a method and device to calibrate such systems quickly and robustly.

Summary of the Invention

[0003] According to the embodiments described in this specification, there is provided a manufacturing system including a dispenser unit movably coupled to a support unit and including a position sensor and a reference detector, a test unit including a test surface that receives material from the dispenser unit and an imaging device that images the material on the test surface, a position reference unit attached to a stationary component of the manufacturing system, and a control unit. The control unit controls the dispenser unit and the reference detector to detect the position reference unit, calibrates the position of the reference detector based on the detection of the position reference unit, controls the test unit to image the material on the test surface, controls the dispenser unit and the reference detector to detect the characteristics of the material on the test surface, compares the image of the material captured by the test unit with the characteristics of the material detected by the reference detector, and is configured to calibrate the test unit based on the comparison.

[0004] According to other embodiments described in this specification, there is provided a method of operating an inkjet printer, including imaging a first image of a printed material deposited on a test surface of the inkjet printer using a first imaging device of the inkjet printer, imaging a second image of the printed material on the test surface using a second imaging device of the inkjet printer, determining a first position of the printed material from the first image, determining a second position of the printed material from the second image, determining a relationship of the first position to the second position, imaging a third image of a plurality of dots printed on the test surface by the inkjet printer using the first imaging device, determining a first position of one of the plurality of dots from the third image, and determining a second position of the one dot by applying a relationship to the first position of the one dot.

[0005] According to other embodiments described herein, using a first imaging device of a manufacturing system to image a test material deposited on a test surface of the manufacturing system by a dispenser unit of the manufacturing system; simultaneously imaging the test material using the first imaging device and imaging a feature portion of a workpiece placed on a workpiece support portion of the manufacturing system using a second imaging device of the manufacturing system; calibrating the first imaging device by comparing a first image of a calibration material deposited on the test surface, captured by the first imaging device, with a second image of the calibration material, captured by a third imaging device of the manufacturing system coupled to the dispenser unit; calibrating the second imaging device based on a position reference portion of the manufacturing system; and calibrating the third imaging device based on the position reference portion. A method is provided that includes these steps.

Brief Description of the Drawings

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Modes for Carrying Out the Invention

[0010] FIG. 1 is a schematic plan view of an additive manufacturing system 100. The additive manufacturing system 100 generally operates by adding material to a workpiece within a fine tolerance of about 1 μm. A dispenser unit 102 is movably provided on a support portion 104, and below the support portion 104, a workpiece support portion 130 for positioning a workpiece that receives material from the dispenser unit 102 is provided. The dispenser unit 102 is typically positioned with extremely high precision so as to discharge material to a desired position of the workpiece with extremely high precision. The dispenser unit 102 includes a dispenser 106 attached to a main body 110 and a position sensor 108. The main body 110 may be a mounting table, a housing, or other components of the dispenser unit 102. Therefore, the dispenser 106 and the position sensor 108 are in a fixed positional relationship with each other (thermal variations are ignored here). To position the dispenser unit 102 so that the dispenser 106 is disposed at a desired position, usually the control unit 112 receives a signal from the position sensor 108 and determines the position of the position sensor 108 from that signal. Since the dispenser 106 and the position sensor 108 are attached to the same object, the position of the dispenser 106 can be determined from the position of the position sensor 108 by applying a fixed offset.

[0011] The control unit 112 determines the position X of the position sensor 108 from the signal s s using a calibration function X to s=f(s) is required, but in many cases, micro-unit errors are not tolerable. A position reference part 114 is attached to the support part 104. The attachment position of the position reference part 114 is a position where the dispenser unit 102 can access the position reference part 114 by moving along the support part 104. The dispenser unit 102 includes a reference detector 116 attached to the main body 110 so as to detect the position reference part 114. To define the calibration function, the dispenser is moved to a calibration position where the reference detector 116 can detect the position reference part 114. The reference detector 116 transmits a signal representing the position of the position reference part 114 in the coordinate system of the reference detector 116 to the control part 112. The control part 112 applies the known position of the position reference part 114 to determine the exact position of the reference detector 116. The control part 112 defines the function f(s) using the relationship between the known fixed position of the reference detector 116 and the position sensor 108, and thus can always accurately grasp the position of the dispenser 106.

[0012] The position sensor 108 can be an encoder in some cases. The reference detector 116 can be a detector using electromagnetism, such as an electric detector, a magnetic detector, an electromagnetic detector, etc. The reference detector 116 can be a high-magnification camera that can resolve details in micro-units. The position reference part 114 may be a reticle or a similar member for high-precision imaging and is used together with the high-magnification camera. In such a case, the control part 112 controls the reference detector 116 to image the image of the position reference part 114, processes the image by image processing software, and determines the position in the local coordinate system (the coordinate system of the reference detector 116). The reference detector 116 can include a light source (not shown) that can be adapted according to the required accuracy of the system.

[0013] The position reference part 114 is generally mounted on the stationary parts of the manufacturing system and serves as a reference position for calibrating each position sensor. The calibration of each position sensor is performed using a reference detector that is movable to reach the position reference part 114. When using an instrument that cannot reach the position reference part 114 but can commonly analyze the object by using the reference detector, the position sensor can be calibrated by calibrating the reference detector using this instrument. Such a calibration method is equivalent to the use of a calibration object traceable to the standard. The reference detector can be positioned using the position sensor calibrated using the position reference part 114 as the standard position. An instrument that cannot reach the position reference part 114 can establish a calibration relationship with the reference detector by performing a common analysis with the reference detector and can be positioned by using the calibration of the reference detector.

[0014] Thermal fluctuations can introduce significant errors that can cause malfunctions in high-precision positioning devices. As long as the temperature is relatively constant, the calibration function f(s) is accurate. However, when there are temperature fluctuations, errors may occur when determining the position of the position sensor 108. Such errors may be grasped by attaching a second position reference part 118 to the support part 104 in addition to the position reference part 114. In that case, the position reference part 114 becomes the first position reference part, and the position reference part 114 is provided at one extreme end of the movement range of the dispenser unit 102, and the second position reference part 118 is provided at the other extreme end of the movement range. The position reference parts 114 and 118 are arranged at a z position such that the dispenser unit 102 can move along the support part 104 without interfering with the position reference parts 114 and 118. By imaging the two position reference parts 114 and 118 using the reference detector 116 and mapping the signals of the position sensor 108 to the determined positions, the errors due to thermal fluctuations can be reduced. By obtaining the calibration points of the position sensor at both extreme ends with different temperatures within the movable range of the dispenser unit 102, the calibration curve X s = f(s, T) can be defined. Naturally, temperature measurement is required in such a method.

[0015] The performance of the dispenser 106 may vary. In such a case, a test unit 120 for analyzing the performance of the dispenser 106 can be provided. The test unit 120 has hardware for detecting the characteristics of the material discharged from the dispenser 106. For example, the test unit 120 can have a test surface 122 for receiving the discharged material and an imaging device 124 for imaging the image of the discharged material and determining the characteristics of the discharged material from the image. For this purpose, in many cases, the position of the discharged material in the captured image is used. To determine the performance characteristics of the dispenser from such data, it is necessary to accurately obtain the position of the dispenser 106 when the material is discharged onto the test surface 122 and the position of the material discharged onto the test surface 122 with respect to a common position reference portion or coordinate system.

[0016] The position of the image of the discharged material on the test surface 122 obtained from the imaging device 124 can be associated with the position of the dispenser 106 using a camera attached to the dispenser unit 102. The camera may be the reference detector 116 or another camera attached to the main body 110 (offset by a predetermined amount from other components attached to the main body). When the reference detector 116 is a high-magnification camera, the dispenser unit 102 can be positioned so as to discharge the material onto the test surface 122, the image of the discharged material can be captured by the imaging device 124, and the image of the discharged material can be captured by the reference detector 116. Using both images, the position of the feature portion of the discharged material such as a droplet or a part of the droplet on the test surface 122 can be determined, and the exact position of the imaging device 124 in the global coordinate system of the manufacturing system can be obtained. Thereafter, using the imaging device 124, the position of the discharged material with respect to the dispenser 106 can be accurately determined, and the relationship between the operation of the dispenser 106 and the position of the discharged material can be precisely constructed, thereby enabling the positioning and operation of the dispenser 106 to be planned.

[0017] Manufacturing system 100 can have a work support part 130 that interacts with a dispenser unit 102 to position a work so that the dispenser unit 102 can deposit materials on the work. The work support part 130 is schematically shown in this specification. The work support part 130 can be of any type. The work support part 130 has a support member 131 movably provided in a positioning part 132, and the work can be moved relative to the dispenser unit 102 by the work support part 130. The work support part 130 has a position sensor 134 that sends a signal of its position to a control part 112, and this position sensor 134 can be an encoder or other sensors. A reference detector 136 is provided at a fixed position relative to the support member 131. In this case, while the reference detector 116 is the first reference detector, the reference detector 136 becomes the second reference detector. The reference detector 136 can be various types of electrical detectors, magnetic detectors, or electromagnetic detectors. In this example, the reference detector 136 is a camera and can be a high-magnification camera.

[0018] The work support part 130 can be moved so that the reference detector 136 can image the second position reference part 118, and the second position reference part 118 can be arranged within the field of view of the reference detector 136. Note that the positioning part 132 can be provided at any suitable position of the manufacturing system 100. The reference detector 136 is mounted at a position where it can interact with the second position reference part 118 in this example, but the reference detector 136 can also be mounted at a position where it can interact with the first reference detector 116. The reference detector 136 images the second position reference part 118, and the digital processing system uses image processing to obtain the position of the feature part of the second position reference part 118 in the coordinate system of the reference detector 116.

[0019] Since the displacement amount from the position sensor 134 of the reference detector 116 is known, the control unit 112 compares the signal from the position sensor 134 received when the work support unit 130 is positioned with the second position reference unit 118 arranged within the field of view of the reference detector 116, with the position of the feature portion of the second position reference unit 118 determined by the reference detector 136, and can define the calibration function of the position sensor 134 in the global coordinate system of the manufacturing system 100. The control unit 112 can determine the precise position of the work support unit 130 from the signal of the position sensor 134 using this calibration function.

[0020] The work is positioned on the work support unit 130 so as to be processed by the manufacturing system 100. In order to precisely drop the material onto the work from the dispenser 106, it is necessary to know the exact position of the work on the work support unit 130. Even if some kind of holder is provided to hold all the work in exactly the same position, it may not be possible to guarantee that no processing errors will occur due to micro-unit errors in the positioning and / or orientation adjustment of the work. The manufacturing system can use the work detector 140 to detect the work placed on the work support unit 130 and detect the exact position and / or orientation of the work on the work support unit 130. The work detector 140 may be a camera that captures an image of the work or a feature portion of the work in order to confirm the position and / or orientation of the work on the work support unit.

[0021] In order to accurately grasp the position of the workpiece in the global coordinate system of the manufacturing system 100, it is necessary to know the precise position of the workpiece detector 140. The workpiece detector 140 can be mounted on any suitable support. In this example, the workpiece detector 140 is movably mounted on the support 104. The workpiece detector 140 can be mounted at a z-position such that the dispenser unit 102 can move along the support 104 without interfering with the workpiece detector 140. In this example, the workpiece detector 140 is mounted on the first side surface of the support 104, and the dispenser unit 102 is mounted on the second side surface opposite to the first side surface of the support 104. The workpiece support 130 can move the workpiece relative to the workpiece detector 140 to a position where the feature portion of the workpiece enters the field of view of the workpiece detector 140. The feature portion is imaged by the workpiece detector 140, and the precise position of the feature portion in the coordinate system of the workpiece detector 140 is obtained using image processing. The workpiece detector 140 has a position sensor 142 such as an encoder, and transmits a signal of the position of the position sensor 142 to the control unit 112. Since the global position of the position sensor 142 can be calibrated using one or both of the position reference portion 114 and the position reference portion 118 as described above, the control unit 112 can confirm the accurate position of the workpiece detector 140. Therefore, the control unit 112 can confirm the accurate position of the workpiece on the workpiece support 130.

[0022] Therefore, the manufacturing system 100 calibrates the position of the dispenser 106, the position of the imaging device 124, the position of the work support 130, and the position of the work relative to the work support 130 in the global coordinate system of the manufacturing system 100. In this way, the control unit 112 receives signals from the position sensor 108 and the position sensor 134, determines the precise position of the dispenser 106 and the precise position of the work supported on the work support 130, and can accurately predict the position where the material is deposited when the dispenser 106 is actuated in the unified coordinate system. The manufacturing system 100 uses any of the stationary position reference parts, or uses a reference detector whose position is calibrated using the stationary position reference part and the detector used during operation to detect the same feature, and calibrates each sensor and the imaging device with respect to the unified coordinate system by comparing the signals from the two detectors. That is, when the stationary position reference part cannot be used for calibrating the sensor, by detecting the reference part using a reference detector calibrated with respect to the stationary position reference part, a non-stationary reference part can be used and the signal of the reference detector can be used as a calibration reference.

[0023] FIG. 2 is a plan view of an inkjet printer 200 including components corresponding to the features described with respect to FIG. 1. The printer 200 has a substrate support portion 202 that supports a printing substrate. A printing support portion 204 is provided across the substrate support portion 202 from one side to the opposite side. The substrate support portion 202 extends in the longitudinal direction and supports the substrate so that it can move relative to the printing support portion 204. A printing assembly 206 is coupled to the printing support portion 204. The printing assembly 206 includes a print head assembly 208 and a motion system 210. The printing support portion 204 includes a printing assembly support portion 212 that extends across the substrate support portion 202 in the transverse direction, and two stands 214 that support the printing assembly support portion 212 on both sides of the substrate support portion 202. The printing assembly 206 is coupled to the printing assembly support portion 212 by the motion system 210, whereby the printing assembly 206 is movable along the printing assembly support portion 212 in the transverse direction of the substrate support portion 202. The substrate support portion 202 and the stands 214 of the printing support portion 204 may be supported on a base 215 to reduce the transmission of ambient movement to the substrate support portion 202 and the printing support portion 204.

[0024] The print head assembly 208 has a housing 216 that includes a print head (not shown) for ejecting printing material onto the substrate. The print head has nozzles exposed on the surface of the housing 216 that faces the substrate support portion 202. The housing 216 also includes a printing material supply device and pneumatic and electrical devices for controlling the ejection of printing material from the nozzles.

[0025] In this embodiment, the substrate support portion 202 is a floating support portion that supports the substrate on a gas cushion so that substantially frictionless movement is possible. The floating support portion allows the substrate to be moved and positioned relative to the printing support portion 204 and the printing assembly 206.

[0026] On one side of the substrate support portion 202, there is a substrate holder assembly 218. The substrate holder assembly 218 includes a substrate holder 220 and a holder support portion 222. The holder support portion extends along the side portion of the substrate support portion 202 in the longitudinal direction of the substrate support portion 202, and the substrate holder 220 is movably coupled to the holder support portion 222 so as to move along the holder support portion 222. The substrate holder 220 engages with the substrate to hold the substrate at a desired position and moves the substrate to a desired position on the substrate support portion 202. The motion system 210 moves the print head assembly 208 in the transverse direction of the substrate support portion 202, and the substrate holder assembly 218 moves the substrate in the longitudinal direction of the substrate support portion 202. In this way, the print head assembly 208 can access and process any position of the substrate.

[0027] Precise dropping of the printing material onto the substrate depends on the precise movement and placement of the print head assembly and the substrate. The control unit 224 has a digital processing system. This processing system is configured to control the actuators of the motion system 210 and the actuators of the substrate holder assembly 218 to achieve the deposition of the material onto the substrate. The motion system 210 has a first position sensor 223, and the substrate holder has a second position sensor 223. Each position sensor 223 may be an encoder, and is operably coupled to the control unit 224 respectively, and transmits a signal representing the position of the motion system 210 and a signal representing the position of the substrate holder 220 respectively.

[0028] The digital processing system of the control unit 224 reads signals from the position sensors of the motion system 210 and the position sensors of the substrate holder 220 to determine their positions, and based on the determined positions and a printing plan including the positions where printing materials are to be deposited on the substrate, determines the desired amounts of movement of the motion system 210 and the substrate holder 220, and is configured to output signals to the motion system 210 and the substrate holder 220 to realize the movement and the deposition of materials onto the substrate. To accurately and precisely position the substrate and the print head assembly and discharge the printing materials, the control unit 224 must be configured to include a calibration function for determining the positions of the motion system 210 and the substrate holder 220 from the received signals.

[0029] To calibrate the control unit 224 with respect to the position sensor of the motion system 210, a high-magnification camera 226 is attached to the housing 216. The high-magnification camera 226 has a field of view that extends toward the substrate support 202. Since the high-magnification camera 226 is attached to the housing at a fixed displacement amount from the position sensor 223 of the motion system 210, an image is captured by the high-magnification camera 226, the position of the feature portion of the image in the coordinate system of the high-magnification camera 226 is specified by image processing software, and by adding the fixed displacement amount from the position sensor 223 of the high-magnification camera 226 to the coordinates of the captured feature portion obtained in the coordinate system of the high-magnification camera 226, the position of the feature portion of the image with respect to the position sensor 223 of the motion system 210 can be determined. When the object imaged by the high-magnification camera 226 is fixed to the upper structure of the printer 200, the image helps to accurately and precisely specify the position of the position sensor 223 in the global coordinate system of the printer 200. By associating this absolute position with the signal obtained from the position sensor 223 at the time the image is taken, a calibration coefficient or calibration function for the control unit 224 to convert the signal from the position sensor 223 into position coordinates in the global coordinate system of the printer 200 is obtained.

[0030] Therefore, the position reference part 228 is attached to a stationary part of the printer 200 at a position where it can be imaged by the high-magnification camera 226. This position reference part is an object that can be imaged by the high-magnification camera 226 in order to confirm the precise coordinates of the feature part of the image. The position reference part 228 may include, for example, a reticle. The position reference part 228 is attached to any one of the stationary parts of the printer 200, such as the stand 214, the print assembly support part 212, the substrate support part 202, the base 215, etc. The position reference part 228 is attached at a position and orientation where the print assembly 206 can move along the print assembly support part 212 and the position reference part 228 can be arranged within the field of view of the high-magnification camera 226. The control unit 224 controls the motion system 210 to move the print assembly 206 so that the position reference part 228 enters the field of view of the high-magnification camera 226, and is also configured to control the high-magnification camera 226 to image the image of the position reference part 228, or the image standard image of the position reference part 228 such as a reticle. The control unit 224 or other digital processing systems are configured to apply image processing techniques to determine the precise position of the feature part of the image in the coordinate system of the high-magnification camera 226. The control unit 224 is configured using the position reference part 228 whose position is known, and calculates coefficients using signals from the position sensors of the motion system 210 sampled when the image of the position reference part 228 is taken, and defines a calibration function of the position sensors of the motion system 210 using the coordinates of the image determined by image processing techniques. In this way, the control unit 224 can convert the signals from the position sensors of the motion system 210 into global coordinates.

[0031] To enhance calibration, a second position reference part 230 can be attached to any of the stationary parts of the printer 200. In this case, the position reference part 228 serves as the first position reference part. The second position reference part 230 can be attached at a position relatively distant from the first position reference part 228 so as to maximize calibration enhancement and assist calibration with respect to other parts of the printer 200. In this case, the first position reference part 228 and the second position reference part 230 are attached to the base 215 on both sides of the base material support part 202 and are arranged in such a direction that the high-magnification camera 226 can access both of them. By performing the same calibration procedure using the high-magnification camera 226 and the second position reference part 230, the coefficient for converting the signal of the position sensor 223 into global coordinates can be made more refined. If necessary, a temperature sensor can be provided in the printer 200, and temperature data related to the coefficient calculated for the position sensor 223 can also be generated. When calibration is performed at different temperatures, a calibration function for converting the signal of the position sensor 223 together with the signal from the temperature sensor into global position coordinates can be obtained.

[0032] The print head of the print head assembly 208 discharges the printing material from the nozzles. Droplets of the printing material are discharged from the nozzles and deposited on the base material. To accurately and precisely deposit the droplets at desired positions on the base material, it is necessary to check the performance of the nozzles, that is, the state of the droplets from when they are discharged from the nozzles until they reach the base material. That is, a function for obtaining the position of the droplets landing on the base material at a distance of z units from the nozzles in the z direction of the global coordinate system when droplets are discharged using a specific stimulus from nozzles located at known coordinates in the global coordinate system must be defined.

[0033] To verify the above function (i.e., the calibration function of the print head assembly, where each nozzle of the print head assembly 208 is paired with an available nozzle stimulus and has a calibration function to obtain the landing position as a function of the nozzle position), a droplet deposition analyzer 232 is used. The droplet deposition analyzer 232 is a device that serves as a surface to receive droplets of the printing material ejected from the nozzles of the print head assembly 208. By using it together with an analyzer 236 such as a high-magnification camera, the characteristics of the deposited droplets are determined. The droplet deposition analyzer 232 can be arranged on the printer 200 at any position accessible to the printing assembly 206. In this example, the droplet deposition analyzer 232 is arranged on the base 215 near one of the stands 214 on the side of the base material support portion 202 opposite to the side where the base material holder assembly 218 is located. Therefore, the droplet deposition analyzer 232 and the base material holder assembly 218 are on opposite sides of the base material support portion 202, respectively. The analyzer 236 is mounted on the side of the print assembly support portion 212 opposite to the side where the housing 216 is arranged. The droplet deposition analyzer 232 can include a positioning portion 238. The surface 234 can be movably coupled to the positioning portion 238 to move the surface 234. The analyzer 236 may also be provided in the positioning portion so that the analyzer 236 can access the droplets deposited at various positions on the surface 234.

[0034] When testing the print head assembly 208 using the droplet dispenser 232, the position of each nozzle of the print head assembly 208 is known in the global coordinate system. This is because the control unit 224 has a calibration function for converting the signal of the position sensor 223 into the global coordinate system of the printer 200. The droplet dispenser 232 is configured to determine the position of the droplet dispensed onto the surface 234. This position is determined in the coordinate system of the droplet dispenser 232. To associate the position of the deposited droplet with the position of the nozzle from which the droplet was ejected, the coordinate system of the droplet dispenser 232 must be converted into the global coordinate system. In this example, the analyzer 236 used to record the position or other characteristic parts of the droplet deposited on the surface 234 cannot be directly calibrated against either of the position reference parts 228 and 230. To calibrate the signal from the analyzer 236 into the global coordinate system, the same deposited droplet is imaged using the droplet dispenser 232 and the high-magnification camera 226, and the position of the deposited droplet is determined. The surface 234 that can be the receiving surface has a reference position feature 240 such as a mark that can be used to specify the position of the deposited droplet in the coordinate system of the high-magnification camera 226 and the coordinate system of the droplet dispenser 232. Based on a simple conversion based on the droplet positions in the two coordinate systems, when the position of the droplet is known in the coordinate system of the droplet dispenser 232, the position of the droplet in the global coordinate system can be obtained.

[0035] Due to the characteristics described above, the nozzle positions of the print head of the print head assembly 208 can be accurately grasped in the global coordinates by using the calibration function of the position sensor 223. Also, the positions of the droplets deposited on the substrate from each nozzle using various available stimuli can be accurately grasped in the global coordinates by using the conversion from the coordinate system of the droplet dispenser to the coordinate system of the high-magnification camera.

[0036] By using a calibration function derived from the signal of a position sensor coupled to the substrate holder assembly 218 and operably coupled to the control unit 224, the position of the substrate can be accurately determined. A high-magnification camera 244 is coupled to the substrate holder assembly 218. The high-magnification camera 244 is coupled to be movable by the substrate holder assembly to a position where the second position reference portion 230 is captured within the field of view. The high-magnification camera 244 images the second position reference portion 230 and, similar to the other movable components described above, can derive the calibration function of the position sensor 223 of the substrate holder assembly 218. Therefore, the control unit 224 can accurately and precisely confirm the position of the substrate holder assembly 218. In order to reduce the thermal error associated with the position of the substrate holder assembly 218, a third position reference portion may be used as described above as needed.

[0037] Finally, when positioning the substrate on the substrate support portion 202 for processing, various errors may occur not only in the positioning of the substrate but also in the structures on the substrate related to the printing plan of the substrate. For example, if structures are formed on the substrate in a previous process and there are errors in the arrangement of those structures, it is necessary to consider those errors in the printing plan of the substrate. Similarly, when the substrate is placed on the substrate support portion 202, if the position is slightly misaligned or the orientation is slightly off, it is also necessary to consider those errors in the printing plan. These errors are usually confirmed and corrected using standard marks on the substrate itself. Usually, a camera is used to image the standard marks, and image processing is applied to confirm the errors in the position and orientation of the substrate on the substrate support portion 202. Using a similar method, it is also possible to confirm the errors before assembly.

[0038] Using the high-magnification camera 226, the exact position and orientation of the marks on the substrate can be confirmed. Based on the printing plan of the substrate supplied to the control unit 224, the control unit 224 controls the substrate holder assembly 218 to position the substrate at a position where the calibration feature portion of the substrate is likely to enter the field of view of the high-magnification camera 226 for imaging. The control unit 224 controls the motion system 210 to position the print head assembly 208 so that the area where the calibration feature portion of the substrate is likely to be included is included in the field of view of the high-magnification camera 226. The control unit 224 images the substrate portion within the field of view of the high-magnification camera 226 and controls the high-magnification camera 226 to obtain the precise position of the calibration feature portion of the substrate in the coordinate system of the high-magnification camera 226 using image processing. The control unit 224 converts the coordinates of the calibration feature portion to global coordinates using the calibration function of the high-magnification camera 226. The control unit 224 can then use the information of the printing plan of the substrate and, based on the detected position of the calibration mark, identify any other arbitrary positions of the substrate, such as corners or centers. These positions can be converted to any other arbitrary positions using the signals of the various calibrated sensors of the printer 200.

[0039] The detection and calibration of the substrate can be quickly performed using a plurality of imaging devices that image the calibration marks on the substrate. For example, when manufacturing a plurality of products from one substrate, the substrate may have a plurality of calibration marks or alignment marks to indicate various boundaries of the products. The printer 200 has a plurality of calibration imaging devices 250 for calibrating the printer 200 with respect to the position and arrangement of the substrate placed on the substrate support portion 202. These imaging devices 250 are supported by the print assembly support portion 212 so as not to interfere with the movement of the print assembly support portion 212. For example, the imaging device 250 may be supported from the bottom of the print assembly support portion 212. By providing a plurality of imaging devices for imaging and identifying a plurality of calibration marks and / or alignment marks on the substrate, the calibration process is speeded up. The imaging device 250 may be a low-magnification camera, a high-magnification camera, or a combination thereof. The imaging device 250 may also be a line image scanner or may include a line image scanner.

[0040] To determine the position and orientation of calibration marks and / or alignment marks on a substrate using a plurality of imaging devices, each of the imaging devices 250 must be precisely calibrated with respect to the global coordinate system of the printer 200. If the imaging device 250 is configured to move to a position where it images one or both of the position reference parts 228, 230, the imaging device 250 can be calibrated directly. Each imaging device 250 images the position reference part and determines the precise position of the feature part of the position reference part in the coordinate system of the imaging device 250. Each imaging device 250 has a position sensor similar to the position sensor 223 and transmits a signal of the precise position of the imaging device 250 to the control unit 224. The control unit 224 associates the signal of the position sensor with the position of the feature part of the position reference part determined by the imaging device 250 to confirm a calibration function or coefficient.

[0041] As shown in the figure, since the imaging device 250 cannot move to image either of the position reference parts 228, 230, the imaging device 250 must be calibrated using the calibration of another device that can be directly calibrated using the position reference parts 228, 230. In this example, a high-magnification camera 226 can be used. Each imaging device 250 images a feature part on the substrate such as a calibration mark or an alignment mark, and the high-magnification camera 226 also images the same feature part. The precise position of the feature part can be grasped from the calibration of the high-magnification camera 226. The position of the feature part obtained from each imaging device 250 is compared with the known position from the high-magnification camera 226, and the relationship between the position confirmed by the imaging device 250 and the global coordinate system can be defined. Therefore, the imaging device 250 can be controlled by the control unit 224 to confirm the position and orientation of the calibration marks and alignment marks on the substrate in the global coordinate system.

[0042] Accordingly, the control unit 224 is configured to calibrate all the position sensors of the printer 200 directly or indirectly with respect to the global coordinate system of the printer 200 based on the position reference units 228 and 230 and also based on the calibration of the high-magnification camera 226 using the position reference units 228 and 230. The indirect calibration is performed by imaging the same object using a camera coupled to the position sensor to be calibrated and the high-magnification camera 226, determining the position of the object using both images, comparing the determined positions, and defining the conversion of the signal from the position sensor to be calibrated to the global coordinate system.

[0043] FIG. 3 is a flowchart showing an overview of a method 300 according to an embodiment. The method 300 includes a dispenser unit movably coupled to a support, a work support movably provided to position a work for processing by the dispenser unit, a test surface that receives a test material from the dispenser unit, and a test detector that detects characteristics of the test material, such as an imaging device that images the test material or a part thereof, to determine performance characteristics of the dispenser unit. The test detector includes a test position sensor that outputs a signal representing the position of the test detector. The dispenser unit includes a dispenser position sensor that outputs a signal representing the position of the dispenser unit on the support. The dispenser unit also includes a first reference detector that can be used to define the position of the dispenser unit based on the signal of the first position sensor. The work support includes a work support position sensor that outputs a signal representing the position of the work support, and a second reference detector that can be used to define the position of the work support based on the signal from the work support position sensor. A work detector is movably coupled to the support to detect the work or a feature of the work. The work detector includes a work detector position sensor that outputs a signal representing the position of the work detector. The various detectors can be an imaging unit or an imaging system including a camera, a photodiode array, a line sensor, or other devices that can precisely perform position detection by rendering an image using any suitable energy medium.

[0044] The manufacturing system can have one or more control units that use a digital processor to control various components and operations of the manufacturing system and collect signals from various sensors and detectors of the manufacturing system. It is possible to control the entire manufacturing system with a single control unit, or to provide dedicated control units for each subsystem such as the test unit, the dispenser unit, and the work support, and for the system control unit to interact hierarchically with the subsystem control units to control the manufacturing system.

[0045] At 302, a test detector is used to detect the test material on the test surface. The test detector may be a camera or other imaging device that captures an image of the test material, and the position of the test material can be determined using image processing. Other characteristics of the test material, such as thickness, spread, uniformity, etc., can also be confirmed from the image of the test material. In some cases, the test material may cover an area of the test surface beyond the range of the detector, such as the field of view. In such cases, multiple images or markers of the test material can be collected by the test detector, and these can be processed individually, sequentially, or simultaneously and integrated into a single image or marker of the test material. The test performed at 302 is carried out to define the performance of the dispenser unit used for depositing the test material. For example, by checking the discharge position of the test material from the dispenser unit and comparing it with the position of the test material on the test surface, it is possible to determine how the material discharged from the dispenser unit reaches the substrate. Using such information, the discharge of the material from the dispenser unit to the workpiece can be planned and precisely executed. The control unit of the manufacturing system or the control unit of the test unit can be configured to control the test unit to perform the operations of step 302.

[0046] In 304, while detecting the test material on the test substrate, a workpiece detector is used to detect the feature portion of the workpiece placed for processing by the manufacturing system. The test detector may be a first imaging device such as a high-magnification camera, and the workpiece detector may be a second imaging device such as a high-magnification camera. By detecting the feature portion, the position and / or orientation of the workpiece can be precisely determined using image processing. The image may be a normal visible light image, or other types of images or markings. The workpiece detector and the test detector are independently movable, positionable, and operable, and thus, for optimizing the preparation of the manufacturing system for processing the workpiece, the detection of the test material and the detection of the feature portion of the workpiece can be performed simultaneously. The control unit of the manufacturing system, or the control unit of the workpiece support unit, can be configured to control the workpiece support unit to perform the operation of step 304.

[0047] In 306, the test detector is calibrated. The test material is deposited on the test surface and detected by the test detector to obtain a first image. The same test material is also detected by a first reference detector to obtain a second image. The first reference detector may be a third imaging device such as a high-magnification camera. For example, data representing each image is created using image processing software or signal processing software, and the two images are compared by comparing these data. From this comparison, the relationship between the image or marking captured by the test detector and the image or marking captured by the reference detector is obtained. Using this relationship, the relationship between the signal of the test position sensor and the position of the test detector can be defined, and thus the position of the test detector when it detects the test material can be grasped. Thereby, the position of the test material can be grasped in a form that can be directly compared with substantially no error with the position of the dispenser unit when the test material is deposited. The control unit of the manufacturing system can be configured to control the test unit, the dispenser unit, and the first reference detector to perform the operation of step 306, and the control unit of the manufacturing system can interact with the control unit of the test unit and the control unit of the dispenser unit to perform the operation of step 306.

[0048] At 308, calibrate the work detector. The position reference part, which is a stationary part of the manufacturing system, serves as a fixed reference point for calibrating the high-precision positioning of various parts of the manufacturing system. The manufacturing system may have a single position reference part or multiple position reference parts. When the dimensions change significantly due to thermal fluctuations, if multiple position reference parts are used, the relative positions of the multiple position reference parts may change, so there is a possibility of being affected by such errors. In such a situation, by calibrating various sensors for the multiple position reference parts, temperature calibration of each part of the manufacturing system can be performed. Even if there are parts in the manufacturing system that cannot be directly calibrated using the position reference part of the manufacturing system, such as parts that cannot interact with the position reference part in a calibratable manner, these parts can be made to interact with another part of the manufacturing system that can be calibrated using the position reference part. Therefore, calibration of another part of the manufacturing system can be performed using the calibration of a certain part with respect to its standard position.

[0049] When the work detector can be arranged to detect the position reference part, the work detector can detect the position reference part, for example, by imaging the image of the position reference part. By obtaining the position of the position reference part and associating this position with the signal from the position sensor of the work detector, the relationship between the signal of the position sensor of the work detector and the position of the work detector can be defined. Using this relationship, the position of the work detector can be confirmed from the signal of the position sensor.

[0050] When the work detector cannot be moved to detect the position reference part, the same feature part of the work can be detected using the first reference detector coupled to the dispenser unit and the work detector. The position of the first reference detector is known from the signal of the dispenser position sensor and the calibration of the first reference detector using the position reference part. By comparing these images, for example, the precise position of the feature part in each image can be identified, and the relationship between the signal of the work position sensor and the position of the feature part in the image can be defined. Thereby, for example, in a common coordinate system, the position of the work detector can be accurately grasped in a form directly comparable to the position of the dispenser unit (and other similarly calibrated components). The control unit of the manufacturing system or other control units can be configured to perform the operation of step 308.

[0051] In 310, the first reference detector is calibrated to define the relationship between the signal of the calibrated dispenser position sensor and the position of the first reference detector. The first reference detector is arranged to detect the position reference part, and the position of the position reference part is obtained, for example, by processing an image using the processor of the control unit. Next, the relationship between the signal of the dispenser position sensor and the position of the position reference part is obtained. The control unit can be configured to define this relationship and perform the operation of calibrating the first reference detector. In this way, the position of the first reference detector is calibrated with respect to the stationary position reference part of the manufacturing system, and by the operation of step 306, the position of the test detector is also calibrated with respect to the same stationary position reference part using the calibration of the first reference detector. The control unit of the manufacturing system or the control unit of the dispenser unit can be configured to perform the operation of step 308.

[0052] In this example, the first reference detector is calibrated against the position reference part of the manufacturing system and used to calibrate at least one other part of the manufacturing system. This shows the concept that by selecting a part that becomes a standard calibration part calibrated against a fixed reference and using that part to calibrate other parts, all parts can be made to operate accurately and precisely according to a common plan. By using such a method, as long as the error between parts is negligibly small or such errors are canceled out by the interaction between parts, there is no need to directly calibrate all parts against the standard position.

[0053] The accuracy of the position information obtained by various calibration relationships is determined by the accuracy and precision of the sensors and detectors, and the accuracy and precision of the parameters derived from the signals and data obtained using the sensors and detectors. The sensors, detectors, and methods can be selected so that any accuracy can be obtained in determining the positions of various parts of the manufacturing system, and the control unit can be configured to repeatedly obtain and apply the calibration relationships. For example, the dimensions and physical characteristics of the parts of the manufacturing system may shift over time due to thermal cycles or the like. By repeatedly executing Method 300 at any time to redefine the calibration relationship, the ability of the manufacturing system to process workpieces precisely can be maintained.

[0054] Note that the work support part can also be calibrated in the same way. As described above, the position of the work support part can be signaled using the work support part position sensor. By coupling the second reference detector to the work support part, it is possible to calibrate the work support part so as to accurately determine the position of the work support part from the signal supplied by the work support part position sensor. The work support part can be moved to place the position reference part or another position reference part within the detection range of the second reference detector. Alternatively, the work support part and the dispenser unit can be arranged so as to detect the same accessible feature, such as a feature part of the work. The feature part can be detected by the first reference detector and the second reference detector calibrated using the position reference part, and the data representation of the feature part obtained from each reference detector can be compared, for example, by the control unit of the manufacturing system. When the position of the first reference detector is known, the relationship between the signal of the work support position sensor and the work support position can be precisely defined in a form that can be directly compared with the positions of other parts of the manufacturing system.

[0055] Figures 4A and 4B are flowcharts showing the outline of method 400 according to other embodiments. Figure 4A shows a part of the method, and Figure 4B shows another part that does not fit on a single page of Figure 4A in the method. Method 400 is a method of operating an inkjet printer such as the inkjet printer 200 of Figure 2. Generally, an inkjet printer that can be used to implement method 400 has a substrate support part and a print head assembly, and the print head assembly is coupled to a support part that enables positioning of the print head assembly so as to deposit a printing material on a substrate placed on the substrate support part. To test the performance of the print head assembly, the inkjet printer has a droplet ejection analyzer for obtaining performance characteristics of the print head assembly, and thus can accurately and precisely eject the printing material onto the substrate. The droplet ejection analyzer has a test surface that receives the printing material from the print head assembly and an imaging device that images the printing material on the test surface. The performance characteristics of the print head assembly can be derived from an image of the printing material imaged by the imaging device of the droplet ejection analyzer. For example, when the precise position of the nozzles of the print head assembly is known when the printing material is deposited on the test surface, by processing a high-magnification image of the printing material on the test surface, the position of, for example, dots of the printing material on the test surface can be precisely confirmed, and the relationship between the position of the nozzles and the deposition position of the droplets ejected from the nozzles on the substrate can be obtained. Using this relationship, printing on the substrate can be accurately and precisely planned.

[0056] Since the pattern of the printing material printed on the test surface may be large and may not be able to be imaged in a single image, the imaging device can be supported on a movable support part and positioned so as to image a plurality of images. The movable support part has a position sensor that transmits a signal of the position of the imaging device. The movable support part usually has a movable range in which the imaging device can be positioned to image an image of the entire printing material pattern, but may not have a movable range that can access a position reference part for calibrating the position sensor.

[0057] A printhead assembly typically has a reference imaging device that can be used to calibrate various components of an inkjet printer. Thus, the imaging device of the droplet analyzer is the first imaging device of the inkjet printer, and the reference imaging device is the second imaging device of the inkjet printer. The reference imaging device is attached to the printhead assembly, and the printhead assembly is movably coupled to a printhead assembly support. The reference imaging device may be a high-magnification camera or other suitable imaging device that provides high-quality images for various purposes including position identification and calibration, substrate inspection, and substrate position calibration. The printhead assembly is coupled to the printhead assembly support by a motion system having a printhead assembly position sensor that signals the position of the printhead assembly on the printhead assembly support.

[0058] Referring to FIG. 4A, at 402, a first image of the printed material deposited on the test surface is captured using the first imaging device, and the first position of the printed material is determined from the first image using, for example, image processing software executed by a digital processor. The processor may be a component of the control unit of the inkjet printer as described elsewhere herein.

[0059] At 404, a second image of the printed material is captured using the second imaging device. The printhead assembly is moved to deposit the printed material within the imaging area of the second imaging device. If the entire pattern of the printed material cannot be captured by the first imaging device or the second imaging device, the same portion of the printed material is captured so that the data obtained from the images of these imaging devices can be compared. The second position of the printed material is similarly determined from the second image.

[0060] At 406, the relationship between the first position and the second position is defined and this relationship can be used to compare the position of the first imaging device relative to the printhead assembly. For example, this relationship can be used to represent the position of the first imaging device and the position of the printhead assembly in a common unit or coordinate system.

[0061] At 408, a third image of a plurality of dots deposited on a test surface using a printhead assembly is imaged using a first imaging device. The first position of one of the plurality of dots is determined, for example, by a control unit of an inkjet printer executing image processing software to determine the third image. Then, the second position of the dot is determined by applying the relationship at 406. The first position may be a position within the reference frame of the first imaging device, such as a coordinate position in the third image. The second position may be a position in the global coordinate system of the inkjet printer, i.e., the common coordinate system. Using the relationship for converting the first position obtained from the local coordinate system to the second position in the global coordinate system, the position of the dot deposited on the test surface can be compared with the position of the nozzle that deposited the dot.

[0062] Although this method is described using the example of printing dots with a printing material, the printing material can be deposited in any suitable form, such as dots, lines, or shapes such as squares, rectangles, crosses, plus signs, etc. By printing and imaging a plurality of types of shapes, the positional relationship between the components of the printer can be confirmed.

[0063] Next, referring to FIG. 4B, at 410, the position reference portion of the inkjet printer can be imaged using a second imaging device. At the same time as imaging the image of the position reference portion, a first signal can be acquired from the position sensor of the second imaging device. The position of the position reference portion in the image is determined, and the relationship between the first signal and the position of the position reference portion is defined.

[0064] The position reference part is a stationary part of an inkjet printer that has a known position in, for example, the global coordinate system, i.e., the common coordinate system, of the inkjet printer as described elsewhere in this specification. The known position can be associated with the first signal of the position sensor, and using the relationship between the first signal and the position of the position reference part, the position of the second imaging device in the global coordinate system can be determined from the first signal. Since the second imaging device is attached to the print head assembly, the position of the print head assembly and the positions of the mounting components such as the nozzles of the print head assembly can be accurately determined from the first signal.

[0065] 412, while imaging the second image of the printing material on the test surface, a second signal is acquired from the position sensor of the second imaging device. To determine the second position, the third position of the printing material in the second image is confirmed. This position can be taken as the position in the local coordinate system of the second imaging device and / or the position in the coordinate system of the image. Then, the second position is determined using the relationship between the first signal from the position sensor of the second imaging device and the position of the position reference part (which may also be the calibration function of the second imaging device).

[0066] Using the third imaging device of the inkjet printer, the characteristic part of the substrate placed on the substrate support part of the inkjet printer can be imaged. Using the image of the characteristic part, the position and orientation of the substrate can be confirmed, and thus the printing plan of the substrate can be accurately and precisely executed. To associate the positioning of the print head assembly with the confirmed precise position and orientation of the substrate, it is necessary to know the position of the third imaging device in a form comparable to the position of the print head assembly. The third imaging device is usually movable so as to easily image the characteristic part of the substrate. The third imaging device is often supported on the same printing support part as the print head assembly by a motion system including a position sensor.

[0067] At 414, an image of the position reference part of the inkjet printer is captured using the third imaging device. At the same time, a first signal is acquired from the position sensor of the third imaging device. The position of the position reference part in the image is determined. This position may be the position in the local coordinate system of the third imaging device or the position of the image itself. The relationship between the position of the position reference part in the image and the first signal from the position sensor of the third imaging device is determined, and using that relationship, the position of the feature part captured by the third imaging device can be determined. In particular, when capturing the feature part of the substrate using the third imaging device, while capturing the image of the feature part, a signal is acquired from the position sensor of the third imaging device, the position of the feature part in the image is determined, and by applying the relationship between the first signal and the position of the position reference part, the position of that feature part can be grasped. The position determined in this way can be compared with the position of the print head assembly determined in the common coordinates from the signal of the position sensor of the print head assembly, so that the printing plan of the substrate can be defined.

[0068] Similarly, other parts of the inkjet printer can be calibrated using the position reference part of the inkjet printer or the calibration of another part calibrated using the position reference part. For example, the inkjet printer may have a substrate holder that moves and positions the substrate during processing. For accurate and precise processing, accurate and precise positioning and movement of the substrate are required, so the position of the substrate holder must be calibrated in the global coordinate system of the inkjet printer so that it can be compared with the position of the print head assembly. The substrate holder is provided with a position sensor and an imaging device, similar to the above-described third imaging device. The position reference part can be imaged using the imaging device of the substrate holder, or the object can be commonly imaged using another imaging device calibrated using the position reference part, such as the second imaging device attached to the print head assembly. Therefore, the position of the substrate holder in the global coordinate system of the inkjet printer can be obtained from the position sensor of the substrate holder.

[0069] While the embodiments relating to one or more aspects of the present invention have been described above, other embodiments not specifically described in this disclosure can be devised without departing from the basic scope of this disclosure, which is defined by the following claims.

Claims

1. A manufacturing system, comprising: A dispenser unit movably coupled to a support unit and including a position sensor and a reference detector; A test unit including a test surface for receiving a material from the dispenser unit and an imaging device for imaging the material on the test surface; A position reference portion attached to a stationary component of the manufacturing system; A control unit, wherein the control unit: Controls the dispenser unit and the reference detector to detect the position reference portion; Calibrates the position of the reference detector based on the detection of the position reference portion; Controls the test unit to image an image of the material on the test surface; Controls the dispenser unit and the reference detector to detect characteristics of the material on the test surface; Compares an image of the material captured by the test unit with the characteristics of the material detected by the reference detector; And is configured to calibrate the test unit based on the comparison. A manufacturing system.

2. The dispenser unit is movable along the support unit to process a workpiece, and the manufacturing system further includes a workpiece detector movably coupled to the support unit. The control unit further: Detects the position reference portion and controls the workpiece detector to calibrate the position of the workpiece detector based on the detection of the position reference portion; The manufacturing system according to claim 1, wherein the workpiece detector is controlled to detect the position of the workpiece.

3. The position reference portion is a first position reference portion, the manufacturing system further includes a second position reference portion, and the control unit further: Controls the dispenser unit and the reference detector to detect the second position reference portion; The manufacturing system according to claim 1, further configured to calibrate the position of the reference detector based on the detection of the second position reference portion.

4. The control unit controls the dispenser unit and the reference detector to detect the first position reference portion and the second position reference portion at a plurality of different temperatures, The manufacturing system according to claim 3, further configured to calibrate the position of the reference detector based on the detection of the first position reference portion and the second position reference portion at the plurality of different temperatures.

5. The reference detector is a first reference detector, and the manufacturing system further includes a work support portion that positions a work for processing by the dispenser unit, The work support portion, A support member that engages with the work, A second reference detector, and the control unit further, Controls the work support portion and the second reference detector to detect the position reference portion, The manufacturing system according to claim 2, configured to calibrate the position of the work support portion based on the detection of the position reference portion.

6. The manufacturing system according to claim 1, wherein the reference detector is a high magnification camera.

7. An operation method of an inkjet printer, Imaging a first image of a printing material deposited on a test surface of the inkjet printer using a first imaging device of the inkjet printer, Imaging a second image of the printing material on the test surface using a second imaging device of the inkjet printer, Determining a first position of the printing material from the first image, Determining a second position of the printing material from the second image, Determining a relationship of the first position to the second position, Using the first imaging device, capturing a third image of a plurality of dots printed on the test surface by the inkjet printer, Determining a first position of one of the plurality of dots from the third image, and Determining a second position of the one dot by applying the relationship to the first position of the one dot, the method comprising.

8. The relationship is a first relationship, Using the second imaging device, capturing an image of the position reference portion of the inkjet printer, While capturing the image of the position reference portion using the second imaging device, obtaining a first signal from a position sensor of the second imaging device, Determining the position of the position reference portion in the image of the position reference portion, and Further comprising determining a second relationship of the first signal with respect to the position of the position reference portion based on the position of the position reference portion in the image of the position reference portion, Determining the second position of the printing material from the second image is While capturing the second image of the printing material on the test surface using the second imaging device, obtaining a second signal from the position sensor of the second imaging device, Determining a third position of the printing material in the second image, and Further comprising applying the second relationship to the third position based on the second signal, the method according to claim 7.

9. The second imaging device is coupled to a print head assembly of the inkjet printer, the print head assembly includes a print head position sensor, and determining the second position of the printing material from the second image includes determining a position in the second image and calculating the second position from the position in the second image based on a signal from the print head position sensor, the method according to claim 7.

10. Using the third imaging device of the inkjet printer to image an image of a feature portion of a substrate, and The method according to claim 7, further comprising determining a position of the feature portion from the image of the feature portion.

11. The relationship is a first relationship, Using the third imaging device to image an image of a position reference portion of the inkjet printer, While imaging the image of the position reference portion using the third imaging device, obtaining a first signal from a position sensor of the third imaging device, Determining a position of the position reference portion in the image of the position reference portion, and Further comprising determining a second relationship of the first signal with respect to the position of the position reference portion based on the position of the position reference portion in the image of the position reference portion, Determining the position of the feature portion from the image of the feature portion is While imaging the image of the feature portion using the third imaging device, obtaining a second signal from the position sensor of the third imaging device, Determining a third position of the feature portion in the second image, and The method according to claim 10, further comprising applying the second relationship to the third position based on the second signal.

12. The second imaging device is coupled to a print head assembly of the inkjet printer, the print head assembly includes a print head position sensor, and determining the second position of the printing material from the second image includes determining a position in the second image and calculating the second position from the position in the second image based on a signal from the print head position sensor. The print head assembly and the third imaging device are each movably coupled to a printing support portion of the inkjet printer. The method according to claim 11.

13. The method according to claim 9, further comprising determining performance characteristics of the printhead assembly based on the second position of the one dot.

14. Imaging a test material deposited on a test surface of the manufacturing system by a dispenser unit of the manufacturing system using a first imaging device of the manufacturing system. While imaging the test material using the first imaging device, imaging a feature of a workpiece placed on a workpiece support of the manufacturing system using a second imaging device of the manufacturing system. Calibrating the first imaging device by comparing a first image of a calibration material deposited on the test surface, captured by the first imaging device, with a second image of the calibration material, captured by a third imaging device of the manufacturing system coupled to the dispenser unit. Calibrating the second imaging device based on a position reference part of the manufacturing system, and A method comprising calibrating the third imaging device based on the position reference part.

15. The method according to claim 14, wherein the position reference part is a first position reference part, and the calibration of the second imaging device is further performed based on a second position reference part.

16. The method according to claim 15, wherein the second imaging device is calibrated based on the first position reference part, the second position reference part, and a plurality of temperatures.

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