TW201609440A - Fast measurement of droplet parameters in industrial printing system - Google Patents

Abstract

A droplet measurement system (DMS) is used in concern with an industrial printer used to fabricate a thin film layer of a flat panel electronic device. A clear tape serves as a printing substrate to receive droplets from hundreds of nozzles simultaneously, while an optics system photographs the deposited droplets through the tape (i.e., through a side opposite the printhead). This permits immediate image analysis of deposited droplets, for parameters such as per-nozzle volume, landing position and other characteristics, without having to substantially reposition the DMS or printhead. The tape can then be advanced and used for a new measurement. By providing such a high degree of concurrency, the described system permits rapid measurement and update of droplet parameters for printers that use hundreds or thousands of nozzles, to provide a real-time understanding of per-nozzle expected droplet parameters, in a manner that can be factored into print planning.

Description

Rapid measurement of droplet parameters in industrial printing systems

The present invention relates to rapid measurement of droplet parameters in an industrial printing system.

More and more industrial processes are turning to printing systems for making product laminates. These printing systems deposit a fluid which is then cured or hardened to form a permanent laminate of a particular product. These processes are particularly useful for microelectronic products or products having an array of quasi-electronic structures. For example, such printing processes are increasingly being used to manufacture a wide variety of thin film electronic displays and solar panels. In addition to the type of fluid used ("ink"), the aforementioned printing system is typically characterized by the use of tens of thousands of printing nozzles on one or more print heads that are designed to be placed close to micron resolution The ability of individual, substantially uniform droplets. This precise control of both the volume and location of the deposited droplets contributes to the high quality of the end product as well as high resolution, small size products and reduced manufacturing costs. For example, in an application, meaning the manufacture of an organic light emitting diode (OLED) display, the ability to accurately deposit ink helps to produce smaller, thinner at lower cost. And better resolution display. Note that when the term "ink" is used to refer to a deposition fluid, the deposition fluid is substantially colorless and is deposited as a structure that will "build" a thickness of one of the permanent laminates of a device, That is, the ink used in traditional graphic printing applications In the sense, the color of the fluid itself is usually not important.

Not surprisingly, in such applications, quality control depends on the uniformity of the deposited ink droplets, in size (droplet volume) and precise position, or at least understood, for the ability to consistently satisfy the stack The permanent stack of layer alignment accuracy and/or quality criteria on the stack homogeneity is important for variations in these characteristics. Please note that in an industrial printing system, the uniformity of droplets for any particular nozzle also has the potential to change over time, whether due to statistical variations, changes in nozzle age, clogging, ink viscosity or compositional variation, temperature, Or other factors may happen.

What is needed is a droplet measurement system that is tuned for use with an industrial printing process, ideally for the in-situ use of a printing system used in an industrial production facility. Ideally, this droplet measurement system will provide one or more droplet parameter measurements that are fast, easy to maintain, and provide inputs that can be used to adjust the print, resulting in precise quality control for industrial product processes. Among them. The present invention addresses these needs and provides other related advantages.

In accordance with one aspect of the present invention, a system for measuring a parameter measurement associated with droplets ejected by a plurality of nozzles of a printhead is disclosed. The system includes: a film having a first side and a second side, the first side being positioned adjacent the print head to provide a substrate for receiving ink droplets from the plurality of nozzles; an image capture subsystem, Positioned to capture an image through the second side of the film, the image representing ink drops received from nozzles located at respective locations of the nozzle, the image capture subsystem for generating an output signal to convey the captured image An image processing system; and a mechanism for advancing the film for a subsequent image capture program Positioning a new portion of the film wherein droplets from a plurality of nozzles of the printhead are received over the first side of the film, the advancement of the film does not require repositioning of the printhead or the image capture subsystem .

In accordance with one aspect of the invention, a droplet parameter measurement method measures a parameter associated with a droplet ejected by a plurality of nozzles of a printhead. The method includes providing a film having a first side and a second side, and positioning the first side adjacent the print head to provide a substrate for receiving ink droplets from the plurality of nozzles; using an image capture device And capturing an image through the second side of the film, the image representing ink droplets received from nozzles located at respective locations of the nozzles, and correspondingly generating an output signal to deliver the captured image to an image processing system; Advancing the film to position a new portion of the film for a subsequent image capture procedure, wherein droplets from a plurality of nozzles of the printhead are received over the first side of the film to a need for the printhead or The image capturing device is repositioned.

According to an aspect of the invention, an apparatus includes: a printing machine for receiving a first substrate, the printing machine having a printing head, the printing head including a plurality of nozzles for ejecting an ink On the first substrate, the ink comprises a liquid which will be hardened on the first substrate to form a permanent laminate of an electronic device thereon, the permanent laminate of the electronic device having a thickness; and a system for measuring a parameter associated with droplets ejected by the plurality of nozzles of the printhead. The system includes: a film having a first side and a second side, the first side being positioned adjacent the print head to provide a second substrate to receive ink droplets from the plurality of nozzles; an image capture a system positioned to capture an image through the second side of the film, the image representing ink drops received from nozzles located at respective locations of the nozzle, the image capture subsystem for generating an output signal to capture the image image Delivered to an image processing system; and a mechanism for advancing the film to position a new portion of the film for a subsequent image capture program, wherein droplets from the plurality of nozzles of the print head are received by the film On one side, the advancement of the film does not require repositioning of the printhead or the image capture subsystem.

101‧‧‧ Flowchart

103-123‧‧‧Steps

201‧‧‧Drop measurement system

203‧‧‧Measurement window

205‧‧ Directions

207‧‧‧Transparent film reel

209‧‧‧vacuum port

211‧‧‧ winch

213‧‧‧Chassis

301‧‧‧Drop measurement system

303‧‧‧View window

305‧‧‧Optical components

307‧‧‧Camera

309‧‧‧Light source

311‧‧‧Stepper motor

313‧‧‧ Directional Arrows

315‧‧‧ winch

317‧‧‧UV curing rod

319‧‧‧Interface and control panel

321‧‧‧film rolling motor

323‧‧‧film rolling motor

403‧‧‧vacuum port

405‧‧‧film belt supply reel

407‧‧‧film tape storage reel

409‧‧‧Frame and optical chamber

411‧‧‧ Directional arrow

412‧‧‧ Directional Arrows

415‧‧‧ Directional Arrows

501‧‧‧Methods for performing droplet measurement

503-533‧‧‧ steps and related projects

551‧‧‧sample image

571‧‧‧sample image

601‧‧‧Different implementation levels

603‧‧‧ Non-transitory machine readable media

605‧‧‧Computer or network

607‧‧‧Storage media

609‧‧‧Manufacture of equipment

611‧‧‧Semi-finished flat panel array

613‧‧‧ portable digital device

615‧‧‧TV display screen

617‧‧‧ solar panels

621‧‧‧Multi-chamber manufacturing equipment

623‧‧‧Transport module

625‧‧‧Printing module

627‧‧‧Processing module

629‧‧‧Input load lock

631‧‧‧Transport chamber

633‧‧‧Environmental buffer chamber

635‧‧‧ hood

636‧‧‧Transport chamber

637‧‧‧Output load lock

639‧‧‧Nitrogen stacking buffer

641‧‧‧Cure chamber

701‧‧‧Drop measurement system

703‧‧‧Print head assembly

705A‧‧ Print head

705B‧‧‧Print head

707‧‧‧Nozzle

708‧‧‧3D coordinate system

709‧‧‧Chassis

711A‧‧‧Mobile system for droplet imaging

711B‧‧‧ plane optical recovery

711C‧‧‧ planar light source supply

713‧‧‧Dimension plane

715‧‧‧Measurement area

717‧‧‧Light source

719‧‧‧Light delivery optics

721‧‧‧Light sensor

723‧‧‧Return optics

725‧‧ ‧focus lens

727‧‧‧ Non-imaging device

731‧‧‧Drop measurement process

733-753‧‧‧ steps and related projects

781‧‧‧Method

783-797‧‧‧ steps and related projects

Typical configuration in 801‧‧‧ industrial manufacturing equipment

803‧‧‧Printing closed chamber

805‧‧‧Second closed environment

807‧‧‧Print head assembly

809‧‧‧ arrow

811‧‧‧Sliding rod

813‧‧‧Substrate

815‧‧‧ floating table

817‧‧‧Drop measurement system

819‧‧‧Parking position

821‧‧‧ arrow

823‧‧‧Dimensional Reference

825‧‧‧Y axis

857‧‧‧Transfer direction

865‧‧‧ nozzle

867‧‧‧Nozzle spacing

901‧‧‧Chart

1001‧‧‧Flowchart

1003-1013‧‧‧ steps and related projects

Figure 1 is a flow chart illustrating a technique for measuring a droplet parameter.

Figure 2 is a close-up perspective view of a droplet measurement system.

Figure 3 is a cross-sectional view of a droplet measuring system.

4A is another perspective view of a drop measurement system.

Figure 4B is a perspective view of a 4A drop measurement system taken from the high point of arrow B-B of Figure 4A.

Figure 5A is a flow diagram associated with an image processing technique used in an embodiment.

Figure 5B is a sample shot image representing one of the droplets deposited on a medium, followed by gray scale conversion.

FIG. 5C is a filtering (eg, gradient processing) of the captured image of FIG. 5B.

6A is an exemplary schematic diagram showing the production hierarchy of associated product manufacturing; the techniques disclosed herein may, but are not limited to, be implemented at any of the levels of the depicted hierarchy.

Figure 6B shows a manufacturing apparatus in one of the plan views.

Figure 7A is an illustrative depiction of the use of a drop measurement system.

Figure 7B is a flow chart for droplet measurement.

Figure 7C is a flow chart for droplet verification.

Figure 8A is a cross-sectional depiction of one of the components located in an industrial printer within a printing chamber.

Figure 8B is a cross-sectional depiction of one of the industrial printers of Figure 8A taken along line B-B of Figure 8A.

Figure 9 is a schematic diagram showing the comparison of the measured drop position relative to one of the respective expected positions.

Figure 10 is a flow chart for the calculation of droplet volume.

The subject matter defined in the claims of the appended claims may be better understood by the following detailed description, and the review of the description should be made in accordance with the drawings. The description of one or more specific embodiments is set forth below to enable various embodiments of the technology listed in the claims of the claims, but is not intended to limit the scope of the claimed application. Instead, explain its application. Without being limited to the foregoing, the present disclosure provides some different examples of a droplet measurement system that optically measures or images a plurality of droplets over a medium and uses image processing to identify those used in industrial manufacturing. One of the parameter values of the various nozzles of the print head. Each of these techniques can be implemented as a drop measurement system, a printer or manufacturing apparatus, or a software for performing the techniques, in the form of a computer, printer, or other device that runs the software, or by These techniques are in the form of an electronic or other device (e.g., a tablet device or other consumer terminal device). Although specific examples are set forth, the principles described herein can be applied to other methods, devices, and systems.

In one embodiment, a droplet measurement system receives ink droplets from various nozzles of one or more printheads, and then uses optical analysis to measure various printhead nozzles associated with various droplets and/or producing such droplets. One of the values of one of the parameters. More specifically, as will be explained below, some embodiments use a deposited film strip (deposition) located in the printer access bracket. Tape) for test printing of inks from various nozzles at the same time. This strip may, in an advantageous embodiment, be any medium capable of receiving ink droplets, and in the notable embodiment described below, it comprises a transparent film that has been specially treated to hold wet ink droplets, Much like photographic paper. Also, in one embodiment, the system is used in an industrial manufacturing facility in which the droplets to be deposited are themselves transparent or translucent (eg, representing a material that will be deposited and cured to form a panel). An encapsulating layer of a device, such as a display or solar panel, or a light-emitting element of such a device. This transparency makes it possible to perform image capture of one or more droplets of a group of nozzles; in an alternative embodiment, droplet deposition can be combined with the film and imaging nozzle position (behind the film) They are separated from each other to provide a very rapid measurement of the droplet position offset (relative to the ideal droplet position) and/or volume and/or timing error associated with droplet deposition.

In one embodiment, one or more print heads are parked in a service station for measurement purposes, for example, when a substrate is loaded or unloaded into the printer (thus, in a printer/manufacture When the equipment is used for other purposes). When the print head is docked, it is incorporated into the drop measurement system in a manner that is aligned with respect to one or more print heads at a particular location to bring a deposition medium (eg, the transparent film described above) into the one or more The proximity of the print head. It then causes a nozzle from one or more printheads (eg, a window or sub-array containing a subset of all nozzles) to eject a droplet or a series of droplets (eg, 2, 5, 10, etc.), The droplets are caused to land on the medium near an intended location of one of the particular nozzles. During or after this period, the film is imaged from the opposite side of the film from the printhead, effectively passing through the transparent film; in other words, the film is accurately positioned at a normal deposition distance relative to the nozzle being measured. (for example, <1.0 mm), and simultaneously (or soon after) simultaneously measuring the nozzles by firing a plurality of nozzles, and then taking an image through the other side of the film to cause the generated captured image to proceed Image processing Droplet parameter value.

Some of the advantages of the features of the various embodiments described so far are noted below. First, the optical processing of the deposited droplets through the transparent film is particularly suitable for extremely large print heads having hundreds to thousands of nozzles, meaning that the optical processing can be performed immediately without additional movement of the printing. Head, droplet measurement system or other components. Second, the droplet measurement system can be grouped to simultaneously measure droplets from multiple nozzles; for example, it is possible to eject droplets from hundreds of nozzles and simultaneously measure. Such simultaneity can greatly facilitate tens of thousands of print head nozzles when compared to systems that optically image (eg, drop one drop at a time) individual droplets in flight (eg, as used in some industrial manufacturing) Drop measurement between applications). For systems that rely on droplet parameter dynamic update measurements, this simultaneity may be important in order to mitigate droplets or compensate for droplets that produce precise target volume variations, as it does not require printing time or manufacturing. There was a significant disruption in output. For a drop measurement system that links one or more docking printheads located in a service station, this provides easy access to any of the thousands of printing nozzles that can be used in some industrial processes. And accurate access. Also, the deposited film strip or its treatment can be specifically tailored to match the chemistry of a particular ink to be tested (ie, its properties can be more conveniently and more accurately determined by optical mechanisms). It should be apparent that the techniques provide enhanced accuracy and lower cost for the manufacture of products, for example, especially for price sensitive consumer products such as flat panel high definition television ("HDTV").

In at least one of the designs described below, the droplet measuring system described above utilizes a roll-to-roll mechanism to load a transparent film that allows the film to be advanced over an imaged area as a film roll, allowing for Intermittent replacement of the measured film roll. In addition, the drop measurement The system can also advantageously utilize a vacuum system that closely adheres the portion of the film strip being deposited, forming a flat and precise positional relationship with one another, simulating a deposition surface for use in-line. The droplet measurement system can also optionally include a curing station to cure/dry the ink such that after the measurement, additional ink is inhibited from diffusing to any other portion of the system; note that this is not the case in some embodiments. If necessary, for example, the film can also be selected or processed to possess the property of allowing the ink droplets to be fixed as soon as they are deposited. Moreover, as previously described, the drop measurement system can be selectively loaded onto a three-dimensional movable carrier, in other words, to engage a docked printhead from below along a vertical (V) axis, and Move along the x (and optionally y) axis as needed to reach different nozzles and different printheads. This allows a "large" printhead assembly (eg, having thousands of nozzles) to be attached to a print plane (eg, in a service bay) and used in the aforementioned drop measurement system. It is fixed when measuring the parameters of nozzles of different groups. A contemplated deposition process advances a roll of film strips such that a window of unused film strips is adjacent to the selected print head, and the print heads are then controlled to cause all of the nozzles to eject a specific amount of ink, which is then secured to the At the same time, a coaxial camera from below (eg, within a housing or chassis of the drop measurement system) images all deposited droplets in parallel with the image sensor (again, by transmitting The image capture of the opposite side of the film strip allows the film and droplet measurement system to be substantially unmoved or repositioned for analysis. If desired, the camera (or image capture optics) can be configured to be movable relative to the drop measurement system, for example, to provide scanning activity, focus adjustment, or other desired benefits between a range of nozzles. .

The output of an image processing system then provides droplet parameter data suitable for verifying the nozzle or otherwise plotting the print. Immediately after any particular measurement iteration step, the film strip And the droplet measurement system is each advanced into position, the film strip used is cured and/or rolled up, and the process is then repeated as needed, or repeated at a later point in time. In a design where the film strip cannot be reused once it has been printed, a used film roll (or a film tape cassette with a reel for the new and used film tape and a winch) can be used as a mold. Group based is periodically recycled or replaced. Note that among a contemplated application, one of the manufacturing mechanisms is used continuously (for example, to print a laminate of OLED television screens, or otherwise fabricate one of a stack of one or more tablet devices), when a previous The substrate is removed, the print head is docked to accept the aforementioned droplet measurement, and as soon as a new subsequent substrate is ready, the measurement progress is stored, the print head returns to the active print job, etc.; The print head is again returned to the service station (when a new substrate is loaded) to begin measurement at the point where the system was previously stopped. In this way, repeated measurements can be collected for the nozzle and used on a scrolling basis to establish a statistical distribution for each print nozzle or nozzle waveform combination through a number of measurements (eg, as in the patent application in the priority statement) The patent applications are incorporated herein by reference, using a mobile measurement window that is cyclically advanced through all of the print nozzle sets to continuously update the measurement data.

Note that all of the process steps listed above (and below) can be implemented in a variety of ways. For example, in one embodiment, the steps are performed by one or more computers or other types of machines by special purpose hardware or by general purpose hardware that is organized to function as a special purpose machine (such as A printing press or one or more manufacturing devices are executed. For example, in a contemplated design, one or more jobs may be performed by one or more such machines, such as firmware or on a non-transitory machine readable medium. The action of the software is controlled under the command. These instructions are written or designed in such a way that they have a specific structure (physical features) that cause one or more general purpose machines (eg, processors, computers) when such instructions are ultimately executed. Or other machine) behaves as a special purpose machine with the structure necessary to perform the described tasks on the input operand to take action or otherwise produce an output. "Non-transitory machine readable media" means any tangible (ie, physical) storage medium, regardless of how the material is stored thereon, including but not limited to, random access memory, hard disk memory, optical Memory, floppy or CD, server storage, volatile memory, and other tangible mechanisms in which instructions can be retrieved later by a machine. The machine readable medium can be in a standalone form (eg, a program disc) or implemented as part of a larger mechanism, such as a laptop, portable device, server, network, printer, Or other device kits consisting of one or more devices. The instructions can be implemented in different formats, for example, implemented as metadata that effectively invokes a particular action when called, implemented as a Java code or script, and implemented as a code written in a particular programming language. (For example, implemented as a C++ code), implemented as a particular processor instruction set, or implemented in some other form; such instructions may also be executed by the same processor or by different processors, depending on the embodiment. Throughout the disclosure, various processes will be described, any of which can be implemented substantially as instructions stored on non-transitory machine readable media, and any of which can use a "3D" Print "or other printed program manufacturing products. Depending on the product design, these products can be manufactured in a form that can be sold, or as a preliminary step in other printing, curing, manufacturing or other processing steps that will ultimately produce finished products for sale, distribution, export. Or import. Depending on the implementation, the instructions located on the non-transitory machine readable medium may be executed by a single computer, and in other cases may be stored and/or executed based on a decentralized basis, for example, using one or Multiple servers, network client devices, or specific application devices. Each of the functions described may be implemented as part of a merge program or as a separate module, stored together in a single media form (eg, a single floppy disk), or Stored on a plurality of storage devices that are separated from each other.

In addition, it should be noted that the term "transparent" is used in conjunction with a film or film strip as a relative term, that is, it means that the first side of one of the film strips is deposited through the second side of the film strip. An image of the droplet above it. Strictly speaking, this does not mean that the film strip must be colorless or, in this case, allow visible light to penetrate. In one embodiment, the film strip is colorless and has a very high visible light transmission, and visible light is used to capture images of droplets from individual nozzles, wherein the droplets are deposited in a manner such that the individual nozzles are The droplets are arranged in an array on the first side of the film strip (ie, at respective locations associated with the respective nozzles). In another embodiment, the film strip has a degree of color, for example, optimized to a particular ink to enhance the image capture properties of the ink. In yet another embodiment, it uses radiation rather than visible light to capture droplet properties.

Various other features will be apparent to those skilled in the art from this disclosure. Having described the features of some embodiments, the following disclosure will instead provide further details regarding selected embodiments.

Figure 1 shows a flow chart 101 illustrating some of the techniques described herein. As previously indicated, it is necessary to simultaneously measure the value of the droplet parameter of the droplets produced by a plurality of nozzles. In order to perform this action as quickly as possible, the embodiments disclosed herein rely on image capture of the deposition surface of one of the droplets (i.e., rapid capture of droplets collectively representing the plurality of nozzles), and photographing from this image. Image processing is performed for one or more desired parameters relative to the plurality of nozzles, respectively. As indicated by reference numeral 103, one or more print heads subjected to analysis cause a range of nozzles or a nozzle array to eject, thereby depositing one or more droplets each. For example, the situation may be that a imaginary print head has two thousand nozzles, and that the nozzles are scheduled to be grouped by one hundred nozzles simultaneously It was measured. For each measurement iteration step, the print head and/or droplet measurement system are aligned, and the window or group of one hundred nozzles to be measured is identified and causes it to eject a controlled amount of ink substantially simultaneously In one embodiment, the deposition described above may be a single droplet per nozzle, while in other embodiments, each nozzle can be controlled to eject a larger number of droplets, for example, 2, 5, 10, 12, 20 or other number of droplets. Note that in some contemplated designs (eg, OLED applications), the droplet size is typically quite small, including picoliter (pL) size droplets with a diameter factor of ten microns or less to near micron precision. Deposition.

As described in the patent application incorporated herein by reference, it may be necessary to measure the location of the deposited droplets, the droplet velocity, the droplet volume, the nozzle warpage, or one of each nozzle, depending on the application. Or multiple other parameters. In short, in one embodiment, for each deposited droplet, it can be expected that the droplet quality of each nozzle is of importance; that is, if one nozzle is relative to the other If it is in the stop position (nozzle warpage) or a droplet trajectory that deviates from the normal rail or an inaccurate droplet volume, this may cause unevenness on a deposited film. This unevenness may result in quality defects on precision products such as display devices. Knowing such defects one by one for the nozzle enables it to be achieved: nozzle pass/fail: it can identify nozzles that are inoperable or have other undesirable characteristics and screen them out of the print job, where the software can be printed. A different nozzle deposits a droplet in a predetermined area; the eruption time is relieved: the position 瑕疵 in the scanning direction can be corrected by changing the nozzle driving pulse with respect to timing or voltage, for example, causing the nozzle to erupt earlier or later , or spray at a greater or lesser speed; in addition, it is also possible to use alternate drive pulse shapes, as in the patent application incorporated by reference in the priority claim. Revealed in it.

Planar droplet combination: the detected difference between the nozzles can be accepted and deliberately used to calculate the droplet combination according to the respective desired values to achieve a precise result, for example, falling within a certain tolerance; For example, if a nozzle is measured and determined to produce an expected 9.89 picoliters (pL) of droplets, a second nozzle is measured and determined to produce the desired 10.11 pL droplet, and it is expected to produce a total When the volume of 20.00 pL of ink is at a specific target position, the two nozzles can be specifically designated and planned to be printed to deposit this particular combination of droplets; note that the results that can be obtained are different from a simple average of differences. a system of specific fill or fill tolerances (eg, target volume ± 0.50%); and pre-screening of drive waveforms: as shown in the patent application incorporated herein by reference, it is possible to pre-screen each nozzle Programmable drive waveforms (eg, selected from sixteen pre-selected drive waveforms) for inventory use during printing, which select each waveform to achieve a particular deposition Accuracy, and expected results.

Please note that the droplet parameters may vary from day to day, even from deposition to deposition, for example, depending on ink quality, temperature, nozzle age (eg, blockage), and other factors. In order to ensure printing accuracy, in some embodiments it may be necessary to re-measure such values from time to time. It should also be noted that each deposited droplet may be slightly different, even from a single nozzle; therefore, in one embodiment, each nozzle (or nozzle waveform combination or pairing) is measured more than once, but Multiple times, the total number is measured cumulatively, and an average or other statistical parameter (eg, a spread measure) can be calculated therefrom to provide a high confidence level for the relevant expected value of the drop parameter. For example, it can measure "24" droplets from each nozzle-waveform pair to average the volume, velocity, warpage (position orthogonal to the scan direction), etc. The value (and thus the expected value of one of the items), where the number n of measurements (n = 24) helps to reduce the uncertainty stemming from measurement errors or statistical variations. It can be based on a scrolling basis (eg, all measurement storage, with 6 latest measurements per nozzle for every two hours replacing the 6 oldest measurements) or based on a one-time basis (eg, during startup) Re-measure all nozzles at a time) Update the total number of measurements. A number of variations are contemplated by those skilled in the art, for example, a nozzle can be measured to determine a desired value, and if the measured (desired) value is outside the ±5% zone of an ideal value, the nozzle is lost. Eligibility for use; many permutations and variations are clearly possible.

However, it should be apparent that in a printing system that uses thousands of nozzles (eg, tens of thousands or more nozzles, perhaps each having multiple "pre-screened" drive waveforms), each Measurement of the expected droplet parameters of a nozzle can take a significant amount of time; in an industrial manufacturing environment, this is generally unacceptable, in other words, if it is to be commercially viable, the manufacturing throughput and cost required for product production. Must be at an acceptable consumer price point, which usually means that the printing process produces as much product as possible, with as high an accuracy as possible (and less product waste), and as small as possible Downtime. The techniques disclosed herein allow far-reaching measurements to make more feasible measurements possible.

Returning to Figure 1, in order to achieve this effect, the droplet measurement technique proposed by the present disclosure also captures droplets from a plurality of nozzles at a time, reference numeral 105. In other words, the embodiment of the present disclosure relies on simultaneity to simultaneously measure as many nozzles as possible, in contrast to systems that image droplets in flight one at a time. Thus, image capture can be used to efficiently take an image containing a plurality of droplets from a large array of nozzles, for example, droplets deposited in multiple rows and columns, which are processed quickly by software in an image processing system. In one embodiment, a captured image may represent droplets from dozens of nozzles, and perhaps hundreds of nozzles (or more), all measured simultaneously. Figure 1 shows in the dashed box various options that can facilitate this goal, for example, (a) by capturing an image (107) through the deposition surface on the opposite side of the printhead, which facilitates velocity measurement, (b) in one Both the droplet and the nozzle are photographed simultaneously in the captured image (109), which assists in the measurement of the positional shift, warpage, or velocity of the droplets from the respective nozzles, and (c) simultaneously from the respective (multiple The droplets of the nozzle are photographed (111), for example, measuring forty or more nozzles at a time, and (d) not every nozzle is photographing one droplet, but simultaneously measuring one containing multiple (for example) , 5 or more) pools of droplets. Note that in the latter case, the image processing software can detect the volume (eg, capacity) of a collection of deposits, or the range of droplet locations near a desired location, and can identify individual droplets from a single shot, Average, or other statistical parameters such as distribution (degree of deviation). Please note that depending on the embodiment, this may require pre-measuring a standard and storing it in the system; for example, when ink droplets are fixed in a deposition medium (ie, a film strip), it may be difficult to detect Measuring the droplet volume; this determination can be determined for the droplet diameter, the color (or gray scale) value of a deposited droplet, or by using its method, and using these values to compare with a calibration standard to produce an accurate Numerical estimate.

As indicated by reference numerals 115 and 117, the system (eg, using an image processor running an appropriate software) then calculates the measured value and stores it in memory (eg, such as in a hard drive) Random access memory). In one embodiment, the values are stored separately (ie, each measurement of each parameter to be measured for each nozzle is stored once), while in another embodiment, it may be It is stored in a manner that represents a mixed distribution (eg, as an average of one of a particular parameter for a particular nozzle, a total number of measurements, a standard deviation, etc.). Referring to reference numerals 119, 121 and 123, as previously described, the measured values can be selectively used to calculate a statistical distribution, to perform nozzle qualification/verification, and to perform" Wisdom combination, where the print scan is mapped to match the droplets with the desired characteristics in some desired way.

2 through 4B are used to depict one embodiment of a modular drop measurement system.

FIG. 2 shows a close-up view of a first such system 201. This view depicts a measurement window 203 (e.g., a glass overlay window) through which images are captured along a vector indicated by reference numeral 205. An optical detector, such as a camera, is located within system 201 and takes a picture through this window 203 in the direction of arrow 205. During operation, a film of transparent film from one of the reels 207 is advanced over the window and is held against the window by a set of vacuum ports 209. Immediately after each measurement, the film strip can be advanced in the direction of the winch 211 and accumulated in a waste roll (not shown) held in a housing 213 of the drop measurement system. Note that the depicted system is modular and moves in a unit, for example, to position the measurement window 203 (and the associated measurement area defined by this window) adjacent to any printhead nozzles to be measured. A "standard deposition depth" relative to the nozzle plate of one of the print heads. In an alternative embodiment, the droplet measurement system 201 can be coupled in three dimensions such that the system can be placed adjacent to other sets of nozzles and the deposition height can be varied as desired.

FIG. 3 shows an internal cross-sectional view of one of the droplet measurement systems 301. The system similarly includes a viewing window 303 through which images are captured, and an optical system including an optical component 305, a camera 307, and a light source 309. A stepper motor 311 selectively advances the optical assembly 305 linearly relative to the viewing window 303, i.e., back and forth in the direction indicated by arrow 313. Please note that in this specification, a "camera" can selectively represent any type of light sensor, that is, it is possible to use a simple line sensor comprising one of the individual optical sensors. And for example, the line sensor is "swept" back and forth to image the entire viewing window 303 with the stepper motor 311. In other embodiments, the camera captures the representative viewing area by any conventional mechanism, for example, using a commercial photoreceptor camera, charge couple device array, ultraviolet or other invisible radiation imaging device, or by other means. An image of one of the pixel arrays. Please note that camera movement (ie, scanning movement) is not necessary for all embodiments. In the depicted embodiment, optical assembly 305 also internally includes a beam splitter that passes light from the source (eg, up to view window 303), but uses one in the direction of camera 307. The mirror turns the returning (reflected) light. It should be apparent that light from the source passes through the viewing window, through the transparent film strip, from the print head (not shown in Figure 3), back through the transparent film strip, and receives any focus or other optical motion, being photographed and Processed for analysis. A captured image thus provides a visual indication of the position of each of the measured nozzles (eg, the image is taken from the nozzle plate) and also displays a stack of any deposited droplets (which are transparent but distinguishable from the film) cover. In other words, among the envisaged processes (especially for OLED display manufacturing, for example, for an encapsulation layer), the deposition material is translucent and therefore does not block image capture of the nozzle plate. Figure 3 also shows a winch 315 for transport of the transparent film strip and a UV curing rod 317 for curing any deposited ink to prevent transfer of deposited ink to any other system components. Figure 3 also shows an interface and control board 319 for controlling various system components and for image capture control; the interface control panel 319 also controls the transport of the film strips, for example, by control, respectively. The film winding motors 321 and 323 are accommodated in a film storage and supply reel (not shown in the drawings). Depending on the embodiment, image processing may be performed at the local end on the interface and control board 319, or alternatively, in a manufacturing device or in a processor located on a remote computer.

4A and 4B show perspective views of the droplet measuring system 301 of Fig. 3. Figure 4B represents a perspective view of the back side of the unit relative to Figure 4A, that is, a view from the high point provided by arrow B-B of Figure 4A. More specifically, these figures show a viewing window 303, a vacuum port 403, a UV curing rod 317, a film strip supply reel 405 and a receiving reel 407, and a frame and optical chamber 409 (this loading Interface and control board 319, as previously described). During operation, it supplies the unused film strip in the direction indicated by arrow 411 and adheres closely to the viewing window 303 as previously mentioned. From this point on, the film is advanced on the winch 315 along arrow 412 toward the UV curing rod 317 for the previously described use. The operation of the aforementioned UV curing rod is controlled by the interface and control board 319, using on-board firmware or software stored in a non-transitory machine readable medium. Finally, after curing, the film is advanced substantially to the receiving reel 407 as indicated by arrow 415. It should be apparent that the entire unit is modular, providing ease of removal and maintenance, for example, removing the storage reel 407 completed by one of the transparent deposited film strips, and replacing the supply reel 405 to have a new Feeding.

Figure 5A presents a flow diagram associated with an embodiment 501 of a method of performing droplet measurement. As previously described, it may be desirable to perform on-site measurements, that is, measurements taken directly within a manufacturing facility to dynamically update the values of one or more droplet parameters for process, age, temperature, or other factors. For this purpose, it advantageously performs measurements in a service station at one of the printers, for example, when a new substrate is being loaded, unloaded, cured after deposition, or other idle period relative to actual printing. Referring to numeral 503, one or more printheads (e.g., loaded to a common printhead assembly) are advanced to the service station and "parked" for inspection operations. This inspection action may include various calibrations, printhead replacements, nozzle cleaning or other quality treatments, droplet measurement as contemplated by the present disclosure, or other uses. As will be more fully explained below, For OLED display manufacturing applications (and the manufacture of certain other devices, such as solar panels), it may be desirable to perform printing in a controlled environment; therefore, in many applications, the "parking" location will be located A second controlled environment chamber, for example, in a position that can be operated externally (e.g., for print head replacement) without the need to interconnect the entire manufacturing facility or printer to an uncontrolled environment. That is, the second chamber is made in a preferred embodiment to have a minor dimension relative to any printed enclosure, for example, two or less percent of the overall print chamber volume. Space to minimize leakage (if any). Once the print head is parked, it is sealed in this second controlled environment, and the aforementioned droplet measurement system ("DMU", representing the droplet measurement unit) is selectively engaged to perform the measurement (505). As noted in the alternative flow block 507, if the printing system moves the window for one of the nozzles (eg, where different nozzle sets are between the printing passes as previously mentioned when the substrate is loaded or unloaded) The measurement or re-measurement is performed on an intermittent basis, and the system captures the start address to locate the DMU and captures the selected subset of nozzles. Note that this process can use an alignment procedure to identify the corner nozzles of each printhead (eg, when a printhead is replaced, so that the system is calibrated to "know" the approximate location of each nozzle). This alignment procedure can be performed by linking the DMUs (and their cameras) described above, and thereby finding the corner nozzles of each array, and using an approximate location addressing and search procedure (eg, a spiral search algorithm). The execution is described, for example, in the U.S. Patent Application Serial No. 14/340,403, which is incorporated herein by reference. The system is very precise in controlling the position of the throwing position, for example, to a precision of about one micron, and usually the recalibration of the position of the droplet measuring system by the print head is not necessary unless a system component is manually replaced (eg , DMU or a print head is removed or repaired). When a transparent film strip (ie, the droplet deposition surface for testing) is positioned, reference numeral 509, The system controls the print head nozzles to deposit a controlled number of droplets each (fast and continuous if each nozzle is scheduled to measure multiple droplets). At the same time, the image capture system within the DMU images the deposited ink and nozzle position (eg, through the transparent film strip and ink, and the light reflected by the print head). Note that, as indicated by reference numeral 511, in one embodiment, image capture is performed in a color manner to be able to identify the ink concentration in any deposited ink droplets (eg, when translucent, it will depend on the material or thickness) Give subtle color properties). As shown by reference numeral 511, a captured image may be filtered (eg, for color, intensity, gamma, or one or more of any other desired parameters) to produce a filtered image; After this filtering action (or as part of this filtering action), the captured image is converted to grayscale, reference numeral 513. Please note that multiple images may also be generated from this process depending on the respective filters, for example, representing a first image of one of the nozzles and a second image representing one of the deposited drops; obviously, there are many variations. The image processing software then uses (one or more) output grayscale images to identify nozzles, ink drops, positional differences between nozzles and ink drops, drop volume, drop diameter, drop shape, and/or any Other required parameters (515/517). It should be apparent that measuring all of the above items is not necessary in all embodiments. For example, in a system that calculates the volume of a drop, it may not require imaging the nozzle itself, or analyzing the shape or location of the drop. Conversely, in this embodiment (if the diffusion range of a plurality of droplets is being analyzed), it is important to determine the magnitude of the deviation of the droplet position or to perform a color analysis to correctly calculate the volume. The measured parameters will essentially depend on the implementation and the desired results. As indicated by reference numeral 517, regardless of what parameters are measured, the system calculates one or more measured values, or an offset of a parameter, for example, using an optional criterion 519, as previously described. This offset or value of a parameter can be applied to the droplet or nozzle position, droplet timing, or droplet volume, or any combination of such items. The calculation is indicated by reference numeral 521. The system then updates one of the DMU's local or remote storage information repository (523), and then stores the location for the next measurement iteration step and advances the film strip, with reference to selective flow 525. The process is thus completed, ready for another measurement iteration step (which can be performed immediately, or at a later point in time, for example, following a subsequent substrate operation round).

Note that the calculation of parameters and/or any positional offsets may be selectively performed by one or more processors running appropriate software (instructions stored on the processor readable medium) as noted by reference numerals 529 through 533. Executing, and the processors generally store image data in the processor-accessible memory, isolate each image data of each nozzle, calculate parameters from the respective image data, and also store each nozzle parameter for processing The device can be accessed in memory.

Figures 5B and 5C show sample images 551 and 571, respectively. The first of these, image 551, represents a photograph taken from a subset of approximately 40 nozzles of a printhead. Note how the nozzles are slightly staggered between columns to provide tight spacing variation among a crossover scan axis (eg, a droplet that is intended to be sprayed toward a particular substrate position can be from either The nozzle columns are printed, which in some embodiments provides better, meaning less than, twenty micron deposition accuracy). Figure 5B represents a color image which can then be filtered and/or converted to a grayscale format as appropriate, and is also a grayscale image after this filtering or conversion action (because the patent application typically does not use or does not allow color) figure). Note that in this embodiment, the nozzles are not separately imaged or depicted, although this may be the case in other embodiments. The second image 571 (Fig. 5C) represents the situation after the image of Fig. 5B is subjected to filtering and gradient processing to identify the droplet diameter. In other words, Figure 5C shows a white circle corresponding to the diameter of the droplet with a clearly distinguishable droplet boundary. Image processing calculates a center of gravity (for example, by calculating the "circle" level of the largest Diameter and vertical maximum diameter and by taking a medial Cartesian coordinate point along each diameter to associate each droplet with a particular xy rectangular coordinate position). This position can then be compared to the nozzle position to determine the offset, and the system recognizes the offset variation between the nozzles for printing planning. Such photographs may also represent droplet volume processing; for example, image processing software may calculate the diameter and/or area of each droplet and/or associated color and associate this with a factory defined standard or a field defined standard. Compare to calculate size and density, and calculate the volume from this. Almost any desired droplet parameter can be measured in this manner.

The above describes a particular drop measurement system, which will be described below for manufacturing and for an industrial manufacturing equipment/printer. In the following description, an exemplary system for performing such printing will be described, and more specifically, for the manufacture of solar panels and/or display devices that can be used in electronic devices (eg, smart phones) , smart watches, tablets, computers, televisions, monitors, or other forms of display). The manufacturing techniques provided by the present disclosure are not limited to this particular scope, and for example, can be applied to any 3D printing application and to a wide variety of other forms of products.

Figure 6A depicts a number of different implementation levels, collectively designated as reference number 601; each of these levels represents one possible independent implementation of the techniques presented herein. First, techniques such as those described in this disclosure can take the form of instructions stored in non-transitory machine readable media, as represented by graphics 603 (eg, to control the execution of a computer or a printer). Instruction or software). For example, the disclosed techniques can be implemented as software that is configured to cause a manufacturing device (or incorporated printer) to measure one or more droplet parameters using the optical measurement techniques disclosed herein. Second, depending on the computer icon 605, these techniques can also be selectively implemented as part of a computer or network, for example, in a design or system. Building components are sold within companies that sell or use other products. Third, as with the use of a storage medium graphic 607, the previously described techniques may take the form of a store control command, for example, when enabled, will cause a printer to rely on droplet measurement and related planning. One or more laminates in a component are fabricated (eg, scan path planning or nozzle qualification verification, as described herein). Please note that the press instructions can be sent directly to a printer, for example, via a LAN or WAN; in this context, the depicted storage media graphics can represent, but are not limited to, internal RAM, or a servo , portable devices, laptops, other forms of computers or a printer-accessible RAM, or portable media such as a pen drive. Fourth, as indicated by the same manufacturing device icon 609, the techniques described above can be implemented as part of a manufacturing apparatus or machine, or as a device or machine (eg, as a droplet measurement system in accordance with the techniques disclosed herein). , as a manufacturing method, as a software for controlling a droplet measuring system, etc.) in the form of one of the internal printing presses. It should be noted that the particular depiction of manufacturing device 609 represents one of the exemplary printer devices that will be described below in conjunction with Figures 6B, 7A, and 7B. The techniques described above can also be implemented as a complete or partially complete fabricated component or a component of a fabricated component (e.g., manufactured according to a patented process); for example, in Figure 6A, some such components are depicted In the form of an array 611 of one of the semi-finished tablet devices, which will be separated and sold for inclusion in the end consumer product. The device depicted can have, for example, one or more encapsulated laminates or other laminates fabricated by the methods described above. The techniques described above may also be implemented in the form of terminal consumer products as described above, for example, in portable digital device 613 (eg, such as an electronic tablet device or smart phone), television display screen 615 (eg, OLED TV) ), solar panel 617, or other type of device.

Figure 6B shows a contemplated multi-chamber manufacturing apparatus 621 that can be used to apply The techniques disclosed herein. In summary, the depicted device 621 includes some general modules or subsystems including a transport module 623, a print module 625, and a processing module 627. Each module maintains a controlled environment, for example, such that printing can be performed by printing module 625 in a first controlled environment, while other processing, such as other deposition procedures such as deposition of an inorganic encapsulation layer, Or a curing process (eg, for printed materials) can be performed in a second controlled environment. Device 621 uses one or more mechanical loaders to move a substrate between the modules without exposing the substrate to an uncontrolled environment. Within any particular module, it is possible to use other substrate handling systems and/or specific devices and control systems to tailor the processing to be performed by the module.

Various embodiments of the transport module 623 can include an input load lock 629 (ie, a chamber that provides buffering between different environments while maintaining a controlled environment), a transport chamber 631 (also having A loader to transport a substrate) and an environmental buffer chamber 633. Within the printing module 625, it is possible to use other substrate handling mechanisms, such as a flotation table, for a stable support of a substrate during a printing process. Additionally, an xyz transfer system, such as a split shaft or overhead transfer system, can be used for precise positioning of at least one printhead relative to the substrate and a y-axis transfer system for transporting the substrate through the print module 625. It is also possible to use a plurality of inks for printing within the printing chamber, for example, using separate print head assemblies such that, for example, two different types of deposition programs can be executed in a printing module located in a controlled environment. . The printing module 625 can include a hood 635 that houses an inkjet printing system, is provided with means for introducing an inert gas environment (eg, nitrogen), and is otherwise controlled for environmental regulation (eg, temperature and pressure). Gas environment, gas composition and dust content.

Various embodiments of a processing module 627 can include, for example, a transport a chamber 636; the delivery chamber also includes a loader for transporting a substrate. In addition, the processing module can also include an output load lock 637, a nitrogen stack buffer 639, and a curing chamber 641. In some applications, the curing chamber can be used to cure, bake or dry a monomer film into a uniform polymer film; for example, two specially contemplated processes include a heating procedure and a UV radiation curing procedure .

In one application, device 621 is tuned for mass production of a liquid crystal display screen or OLED display screen, for example, on a single large substrate, an array of, for example, eight screens at a time. These screens can be used for televisions and as display screens for other forms of electronic devices. In a second application, the device can be used in mass production of solar panels in much the same way.

Print module 625 can advantageously be used in applications in which such organic encapsulation stacks are deposited, and such organic encapsulation stacks help to protect sensitive components of OLED display devices. For example, the depicted device 621 can be loaded into a substrate and can be controlled to move the substrate back and forth between the chambers in a manner that is not interrupted by exposure to an uncontrolled environment during the encapsulation process. . The substrate can be loaded via the input load lock 629. One of the handlers located in the transport module 623 can move the substrate from the input load lock 629 to the print module 625, and, immediately after a printing process is completed, the substrate can be moved to the processing module 627 for curing. Each of the controlled thickness, pooled encapsulation, or other laminate thickness can be established to fit any desired application by repeated deposition of subsequent laminates. Also note that the above techniques are not limited to encapsulation processes or OLED fabrication, and that many different types of tools can be used. For example, the configuration of device 621 can be altered to place the various modules 623, 625, and 627 in different juxtaposed positions; in addition, more, fewer, or different modules can be used.

While Figure 6B provides an example of a set of joining chambers or manufacturing components, many other possibilities are apparent. The techniques described above can be used in conjunction with the apparatus depicted in Figure 6B, or even to control a process performed by any other type of deposition apparatus.

Figures 7A through 7C are used to generally introduce techniques and structures for use in nozzle-by-nozzle drop measurement and verification.

More specifically, FIG. 7A provides an illustrative view depicting a drop measurement system 701 and a relatively large printhead assembly 703 having a plurality of print heads (705A/705B) each having a plurality of individual nozzles ( For example, 707), where there are thousands of nozzles. An ink supply (not shown) is fluidly connected to each nozzle (e.g., nozzle 707), and a piezoelectric sensor (not shown) is used under the control of a nozzle-by-nozzle motor control signal. Spray ink droplets. The design of the nozzle maintains a slightly negative ink pressure at each nozzle (eg, nozzle 707) to avoid flooding of the nozzle plate, wherein an electrical signal of a particular nozzle is used to activate the corresponding piezoelectric sensor, A particular nozzle pressurizes and thereby ejects droplets from the particular nozzle. In one embodiment, the control signal for each nozzle is normally at zero volts, and the droplets of the nozzle are ejected with a positive pulse or signal level at a particular voltage for a particular nozzle ( One drop per pulse); in another embodiment, different pulses (or other more complex waveforms) that have been trimmed can be used between the various nozzles. However, in conjunction with the example provided in Figure 7A, it should be assumed that it is required to measure a droplet volume produced by a particular nozzle or a particular nozzle set (e.g., nozzle 707), wherein a droplet is deposited from the printhead toward the load. One of the films, the chassis 709, is ejected downward (i.e., in a direction "h" that represents the z-axis height relative to a three-dimensional coordinate system 708). As described earlier, for embodiments using existing droplet deposition from a number of nozzles, a target surface is advantageously secured to a known position relative to the printhead (eg, such that it knows which sinks Which nozzle the product droplet belongs to). The above "h" is usually on the order of one millimeter or less, and there are thousands of nozzles (for example, 10,000) in which individual droplets are individually measured in this manner in an operating printer. Nozzles) in which the deposition surface is incrementally changed or advanced to a plurality of droplets (eg, tens to hundreds) of multiple windows that will be simultaneously imaged and measured. Thus, in order to accurately measure droplets from each nozzle, it uses specific techniques in the disclosed embodiments to properly position the droplet measurement system 701, printhead assembly 703, or both relative to one another. Components for optical measurements.

In one embodiment, the techniques use a combination of: (a) at least a portion of the optical system's xy motion control (711A) (eg, within dimension plane 713) to accurately position a measurement region 715, The measurement zone 715 is provided by a system of nozzles or nozzle sets that are immediately adjacent to produce droplets for optical calibration/measurement, and (b) in-plane optical recovery (711B) (eg, allowing immediate proximity to any nozzle) The easy measurement of the measurement area, even under the surface area of a large print head). Thus, in an exemplary environment having about 10,000 or more print nozzles, the mobile system is capable of, for example, about 10,000 discrete locations near the discharge path of each individual nozzle in the printhead assembly. Positioning at least part of the optical system. The optics are typically adjusted to position such that precise focus is maintained over the measurement area to capture deposited droplets on a transparent film or other deposition medium, as previously described. Note that the diameter of a typical drop can be on the order of microns, so optical placement is typically quite sophisticated and challenging in terms of the relative positioning of the printhead assembly to the measurement optics/measurement area. In some embodiments, to assist in this positioning, optics (mirrors, cymbals, etc.) are used to adjust the orientation of one of the light-harvesting paths under the dimension plane 713 from the measurement region 715. So that the measuring optics can be placed close to the measurement area without interfering with the optical system Relative positioning with the print head. This enables efficient position control in a manner that is not limited to the deposition height of the millimeters of deposition and imaging of each droplet, or the large x and y widths occupied by the inspected printhead. Alternatively, different beams incident from different angles can be used to image a film or deposition surface from below, or it can also be used with a coaxial image capture system having a beam splitter. Other optical measurement techniques can also be used. Among one of the selective features of such systems, the mobile system 711A is selectively and advantageously fabricated as an xyz transfer system that enables the droplet measurement system to selectively move under the unprinted printhead assembly during droplet measurement Engage and separate. In short, it is conceived that in an industrial manufacturing device with one or more large print head assemblies, each print head assembly will be "parked" from time to time in order to maximize the normal operating time of production. The service station performs one or more inspection functions; taking into account the sheer size of the number of print heads and nozzles, it may be desirable to perform multiple inspection functions at a time on different parts of the print head. To this end, in this embodiment, it may be advantageous to move the measurement/calibration device around the printhead rather than moving the printhead around the devices. [This thus allows for the addition of other non-optical inspection procedures, for example, for other nozzles, if necessary. To facilitate such actions, the printhead assembly can be selectively "parked", as specified above, with the system designating a particular group or range of nozzles, intended to be the protagonist of the optical calibration. Once the printhead assembly or a particular printhead is stationary, the mobile system 711A is added to move at least a portion of the optical system relative to the "parking" printhead assembly and accurately position the measurement region 715 for a suitable detection. The position of the droplets ejected from a group of individual nozzles; using a z-axis movement such that it selectively engages the light-recovering optics from substantially below the plane of the printhead, alternatively or additionally contributing to optical calibration Other overhaul actions. Perhaps in other words, the use of an xyz mobile system enables selective engagement of the droplet measurement system independent of the one used in a service station environment He tests or tests outside the device. For example, in such a system, one or more printheads in a printhead assembly can also be selectively replaced while the printhead is parked. Please note that this structure is not necessary for all embodiments; other alternatives are also possible, such as where only the print head assembly moves (or one of the print heads moves) and the measurement assembly is stationary, or where there is no need to park the print head Component.

In summary, the optics used for droplet measurement will include a light source 717, a selective set 719 of light delivery optics (this is required to direct light from source 717 to measurement area 715), one or more lights. A sensor 721, and a set of recovery optics 723 that direct light for measuring the droplet(s) from the measurement region 715 to the one or more photo sensors 721. The mobile system 711A selectively moves any one or more of these elements together with the chassis 709 (eg, with the imaging area) in a manner that allows the light of the post-droplet measurement to be directed from the measurement area 715 to a position below a plane. ). In one embodiment, light delivery optics 719 and/or light return optics 723 use mirrors that are directed back and forth between measurement regions 715 along a vertical dimension parallel to the direction of travel of the droplets. Light, with the mobile system moving each of the elements 709, 717, 719, 721, and 723, becomes an integrated system during droplet measurement; this arrangement has the advantage that focusing does not require recalibration relative to the measurement area 715. As indicated by reference numeral 711C, the light delivery optics are also selectively used to supply source light from a location below the dimension plane 713 of the measurement area, for example, with a light source 717 and (s) light sensor(s). Both 721 conduct/collect light from below the measurement area, as summarized in the figure. As noted by reference numerals 725 and 727, the optical system can optionally include lenses for focusing purposes, as well as photodetectors (e.g., for non-imaging techniques that do not rely on processing a multi-pixel "image"). Also note that at any point during the "stop" period of the printhead assembly, the z-movement control is selectively used for the chassis to enable the optical system to Selectively engage and disengage and facilitate precise positioning of the measurement region 715 near the nozzles of any group. The docking of such a printhead assembly 703 and the xyz movement of the optical system 701 are not necessary for all embodiments. Other kinds of permutations and combinations are also possible.

Figure 7B provides a flow of a procedure associated with droplet measurement of some embodiments. This program flow is generally indicated by reference numeral 731 in Fig. 7B. More specifically, as shown by reference numeral 733, in this particular procedure, the printhead assembly is first parked, for example, at a service station (not shown) of a printing press or deposition apparatus. in. A droplet measuring device then engages (735) the printhead assembly, for example, by selective engagement of a portion or the entirety of a droplet measurement system, by moving from below a deposition plane into a droplet measurement system An optical system is capable of simultaneously measuring the position of droplets from a plurality of nozzles. Referring to numeral 737, the movement of one or more optical system components relative to a docking printhead can be selectively performed in the x, y, and z dimensions.

As described in the patent application incorporated herein by reference, even a single nozzle and associated nozzle erupts the drive waveform (ie, the pulse or signal level(s) used to eject a droplet It is also possible to produce droplet volumes, trajectories, and velocities that differ slightly between droplets. In accordance with the teachings herein, in one embodiment, the aforementioned drop measurement system, as indicated by reference numeral 739, selectively takes n measurements of a desired parameter per drop to derive an expected property for the parameter. Statistical credibility. In one embodiment, the measured parameter may be a volume, but for other embodiments, the measured parameter may be flight speed, flight trajectory, nozzle position error (eg, nozzle warpage) or other parameters, or multiple A combination of one of these parameters. In an embodiment, "n" may vary with each nozzle, but in another embodiment, "n" may be a fixed number of measurements (eg, "24") that each nozzle is scheduled to perform; In yet another implementation In the mode, "n" represents a minimum number of measurements such that more measurements can be performed to dynamically adjust the measured statistical properties of the parameters or to increase the confidence. Obviously, there may be many variations. In conjunction with the previously described system, a total number of measurements can be established immediately (ie, by performing multiple droplet measurements on a particular nozzle array during a single measurement iteration step, in other words, not moving the droplet measurement system to one Different nozzle sets), or by making a single measurement and establishing a total number of measurements through later measurements (eg, when the measurement continues through a circular range of nozzles over time).

With respect to the example provided in Figure 7B, it should be assumed that the droplet volume is being measured to obtain an accurate average representing one of the expected droplet volumes from a particular nozzle and a compact confidence interval. This facilitates the selective patterning of droplet combinations (using multiple nozzles and/or drive waveforms) while reliably maintaining the distribution of mixed ink fills in one target area near the intended target (ie, relative to the droplet average) Mix). As noted in the alternative flow blocks 741 and 743, the contemplated optical measurement process desirably facilitates a one-time, immediate or near-instant measurement and calculation of the volume of many nozzles (or other desired parameters), for example, using a transparent film And the photographing below the deposition plane (ie, from the opposite side of the film used for deposition); with this rapid measurement, it becomes possible to update the volume measurement frequently and dynamically, for example, to compensate for ink properties (including viscous and constituent materials) , temperature, nozzle blockage or aging, and other factors over time. Based on this, for example, with a printhead assembly containing 10,000 nozzles, it is expected that the total number of huge measurements of each of the thousands of nozzles can be taken in minutes, enabling it to be executed frequently and dynamically Droplet measurement. As described earlier, in an alternative embodiment, droplet measurements (or measurements of other parameters such as trajectory and/or velocity) can be performed as a periodic intermittent program, depending on the schedule or inter-substrate Between the droplet measurement system (for example, when the substrate is being loaded or unloaded), or stacked under other components and/or other printhead inspection procedures to efficiently collect many data over many measurement intervals Points (and thus establish a statistical distribution representing one of each nozzle). Note that this embodiment of the rapid measurement system facilitates scan path adjustment, nozzle pass/disqualification verification, and various nozzle waveform pairings for embodiments that allow alternate nozzle drive waveforms to be used in a specific nozzle-specific manner. The combination of the droplets of the droplets is abbreviated as previously mentioned in the patent application filed herein by reference. Referring to reference numerals 745 and 747, by measuring the expected droplet volume to an accuracy of better than 0.01 pL, it becomes possible to plan a very accurate droplet usage pattern, wherein the use of droplets can also be planned (in an ideal In case) to 0.01 pL resolution, and wherein the measurement error in an embodiment is effectively reduced to provide 3 σ (or other statistical values such as 4 σ , 5 σ relative to the allowable drop volume) , 6 σ , etc.) the credibility. The same holds true for droplet position and/or velocity and/or nozzle warpage. For example, by measuring the expected position to an accuracy better than one micron (or another distance magnitude), it becomes possible to provide very accurate deposition; the expected position can be measured to a specific right angle coordinate point and standard Within a certain range of the difference (or, for example, 4 σ , 5 σ , 6 σ degrees near this point). Once sufficient measurements are made for the various droplets, the filling involving the combination of such droplets can be evaluated and used to print (748) by the most efficient way possible. As shown by divider 749, the execution of the droplet measurement can be intermittently switched back and forth between the current "online" printing process and the "offline" measurement and calibration procedure; note that in order to minimize manufacturing system downtime, such Measurements are typically performed when a printer, such as during substrate loading and unloading, is assigned to other programs. Referring to numeral 751, in one embodiment, a transparent film or film strip can be specifically selected (or treated) to optimize the droplet properties of the particular ink being analyzed (ie, the particular chemical or fluid properties of the ink). Capture for auxiliary image capture and/or analysis. For example, in some applications, the ink will be later cured by a UV curing process to convert into a monomer of a polymer; to aid in the trapping of droplet properties, the transparent film It can be selected to have physical, color, absorptive, fixed, cured, or other properties to enhance the predictive conditions for analyzing this material using an imaging system. Finally, reference numeral 753, the film (film strip) or the droplet measurement system as a whole (or both) can be designed for modular replacement to minimize measurement system and printing system downtime.

During printing, nozzle (and nozzle waveform) measurements can be made based on a scrolling basis, propelled through a range of nozzles, and each interruption occurs between substrate printing actions. The same basic procedure of Figure 7B can be used to make measurements whether or not engaged to re-measure all nozzles, or based on the basis of this scrolling. To this end, when a droplet measuring device is added for a new measurement (following the previous measurement or immediately after a substrate printing action), the system software loads an indicator indicating the next one scheduled to be measured. Nozzle set (for example, for a second print head, "the upper left corner is at the nozzle window at nozzles 2, 312"). In the case of an initial measurement (eg, in response to a new print head installation, or a recent power-on, or a periodic program such as a daily measurement procedure), the above indicator will point to one of the first nozzles of a printhead. For example, "Nozzle 2, 001". This nozzle is associated with a particular imaging grid access or from a memory lookup. The system uses the provided address to advance the droplet measurement system (eg, the previously described measurement area) to a position corresponding to the intended nozzle position. Note that in a typical system, the mechanical throwing position associated with this movement is quite accurate, in other words, reaching a resolution of approximately micron. At this point the system selectively searches for nozzle positions near the expected micro-resolution position and finds the center of the nozzle and its position based on image analysis of the print head within a tiny micron distance from the estimated grid position. For example, a zigzag, spiral or other search mode can be used to target the desired set A nozzle or reference point of a particular positional relationship searches for the desired position. A typical spacing distance between the nozzles can be on the order of 250 microns, while the nozzle diameter can be on the order of 10 to 20 microns.

Figure 7C provides a flow chart for nozzle qualification verification. In an embodiment, the droplet measurement is performed to generate a statistical model for each of the droplet volume, velocity, and trajectory and/or for each of the nozzles and each waveform for each particular nozzle. (for example, distribution profile and average). Thus, for example, if there are two waveform choices for twelve nozzles, there are up to 24 waveform-nozzle combinations or pairs; in one embodiment, for each nozzle or waveform-nozzle pairing The number of measurements taken for each parameter (eg, volume) is sufficient to develop a robust statistical model. Note that despite the specification, a particular nozzle or nozzle-waveform pairing is conceptually still likely to produce an unusually broad distribution, or an average that is too far off the track and should be specially processed. The particular processing of this application is conceptually depicted in Figure 1C by an embodiment.

More specifically, it generally represents a method using reference numeral 781. The data generated by the droplet measuring device is stored in the memory 785 for later use. During application method 781, this data is recalled from memory and each nozzle or nozzle-waveform paired data is extracted and processed individually (783). In one embodiment, it establishes a normal random distribution for each variable that is qualified for verification, defined by an average, standard deviation, and number of measured drops (n), or an equivalent magnitude. Note that it can use other distribution formats (for example, Student's-T, Poisson, etc.). The measurement parameters are compared (787) to one or more ranges to determine if the associated droplets can be actually used. In one embodiment, at least one range is used to eliminate eligibility for the droplet to be used (eg, if the droplet has an oversized or undersized volume relative to the desired target, the nozzle or nozzle-waveform pairing can be excluded Short-term use). To provide an example, nozzles or nozzle-waveform pairings that are connected to droplet averages exceeding this target, such as 1.5% (eg, <9.85 pL or > 10.15 pL), can be excluded if 10.00 pL of droplets are required. It may also use or alternatively use ranges, standard deviations, variances, or other metrics. For example, if you want a statistical model of a drop with a narrow square (for example, an average of 3 σ < 1.005%), droplets whose measured values do not meet this criterion can be excluded. It is also possible to use a set of sophisticated/complex criteria that take into account multiple factors. For example, an abnormal average combined with a very narrow deviation may be acceptable, for example, if the deviation (eg, 3 σ ) deviates from the measured (eg, abnormal) average μ, which is within 1.005%, then A related droplet. For example, if you want to use a droplet with a 3 σ volume within 10.00pL ± 0.1pL, you can exclude the generation of a nozzle-waveform pair with a mean value of 9.96pL with a ±0.8pL 3 σ value, but A nozzle-waveform pairing with one of 0.93 pL average values of one ±0.3 pL 3 σ value may be acceptable. Obviously, there are many possibilities depending on any required rejection/abnormal criteria (789). Note that this same type of processing can be applied to the flight angle and velocity of each droplet, meaning that it predicts a statistical distribution of the flight angle and velocity of each nozzle-waveform pairing, and depends on the derivation from the droplet measurement. Measurements and statistical models of the device, some droplets can be excluded. For example, a droplet whose average velocity or flight trajectory deviates from the normal value of 5%, or the variance of the velocity outside a specific target, can be assumed to be excluded. Different ranges and/or evaluation criteria can be applied to each drop parameter 785 measured and provided by the reservoir.

Note that depending on the rejection/abnormal criteria 789, the droplets (and nozzle-waveform combinations) can be processed and treated differently. For example, it can reject a particular drop (791) that does not meet a desired standard, as previously described. Or it may be for a special nozzle-waveform pairing The next measurement iteration step selectively performs more measurements; for example, if a statistical distribution is too wide, it is possible to perform more measurements specifically for that particular nozzle-waveform pairing to improve this by more measurements The tightness of the statistical distribution (for example, the number of variances and the standard deviation depends on the number of data points measured). Referring to reference numeral 793, it is also possible to adjust a nozzle drive waveform, for example, to use a higher or lower voltage level (e.g., to provide a greater or lesser speed or a more consistent flight angle), or to reshape A waveform is generated to produce a nozzle-waveform pairing that meets one of the specified criteria. Referring to reference numeral 794, the timing of the waveform can also be adjusted (e.g., to compensate for the abnormal mean speed associated with a particular nozzle-waveform pairing). For example (previously mentioned a little), a slow drop can be ejected at an earlier point relative to the other nozzles, while a fast drop can be ejected slower in time to compensate for faster flight times. . Many of these alternatives are possible. Finally, reference numeral 795, any adjusted parameters (eg, eruption time, waveform voltage level or shape) can be stored, and, optionally, the adjusted parameters can be overridden if desired. One or more associated droplets. After each nozzle-waveform pairing (modified or otherwise processed) is verified (pass or fail), the method then proceeds to the next nozzle-waveform pairing, reference numeral 797.

The foregoing mechanism can also be used to measure nozzle warpage (and, of course, to verify the conformity of the nozzle based on this). In other words, for example, if it assumes that a group of deposited droplets originate from a single common precise nozzle position but is concentrated off-center in a direction orthogonal to the scanning movement of the printhead substrate, the nozzles involved may be in the same position The nozzles on the column or on the same row are offset. Such anomalous offset may result in an idealized droplet ejecting deviation, which may be taken into account when planning the precise combination of droplets, in other words any such "warping" or individual nozzle offsets are stored and used. Verify pass/fail of the nozzle or as part of the print scan plan, As previously described, the printing system is allowed to utilize the differences in each individual nozzle in a planned manner rather than attempting to flatten the differences using the averaging. Among a selective variation, the same technique can be used to determine the irregular nozzle spacing along the print head scanning direction (ie, the fast printing axis), although for the depicted embodiment, any such Errors are all attributed to corrections for droplet velocity deviations (eg, any such spacing error can be adjusted by correcting the nozzle speed, for example, due to minor changes to the drive waveform for that particular nozzle By). In order to determine the warp across the scan axis of one of the nozzles that produces a cluster of droplets, the individual tracks are actually reversed (or otherwise mathematically applied) relative to other measured tracks of the same nozzle and used to identify the view. One of the specific nozzles averages across the scan axis position. This position may deviate from the expected position of one of the nozzles, which may be evidence of nozzle warpage.

As previously mentioned and as the meaning of this description implies, an embodiment establishes a statistical distribution of each nozzle for each measured parameter, for example, for volume, velocity, trajectory, nozzle warpage, and possibly other parameters. . As part of this statistical process, individual measurements can be discarded or used to identify errors. As an example, if a drop measurement is found to have been removed from other measurements of the same nozzle so far, the measurement may represent an eruption or measurement error; in one embodiment, if it deviates To a point above a statistical error parameter, the system discards this measurement. If no droplets are seen at all, this may be evidence that the droplet measurement system is at the wrong nozzle (wrong position), or that there is an eruption waveform error or a nozzle failure under one view. It can use a fault handling procedure to make appropriate adjustments, including taking any new or further measurements as needed.

Note that although Figures 7A through 7C are not individually invoked, they basically perform the depicted measurement procedure for each of the available alternate waveforms used in conjunction with each nozzle. Lift For example, if each nozzle has four different piezoelectric drive waveforms to choose from, the measurement procedure may generally be repeated 4 times for each group of nozzles; if a particular implementation requires The 24 droplets of the waveform establish a statistical distribution, and a nozzle can have 96 such measurements (four waveforms each 24 times), where one measurement is used to determine the velocity, velocity, and volume of the droplet. One, and the statistical mean and off-estimate of the estimated nozzle position (eg, used to evaluate nozzle warpage). In an contemplated embodiment, any number of waveforms can be shaped or otherwise generated, and the system measures droplet parameters associated with one or more preselected waveforms and thereby stores the parameters for subsequent use in printing and / or print planning. These parameters can also be used to determine whether to maintain (and store) waveforms for use in printing (eg, as part of a pre-selected set of allowed waveforms), or to select a different waveform and measure multiple of that waveform. parameter.

Through the use of precision mechanical systems and droplet measurement techniques, the disclosed method allows for extremely high accuracy measurements of individual nozzle characteristics, including the average of each of the aforementioned parameters (eg, volume, velocity, trajectory, nozzle position, and other parameters). Droplet measurement. As can be appreciated, the described techniques facilitate a high degree of consistency in the process, particularly OLED device processes, and thus enhance reliability. By providing control efficiency, especially for droplet measurement speeds and stacking these measurements in other system programs in a way that is calculated to reduce overall system downtime, the teachings presented above help to provide a more A fast and less expensive process designed to provide flexibility and precision in the manufacturing process.

Figure 8A shows a cross-sectional view (e.g., associated with one of the printers) 801 of a typical configuration within an industrial manufacturing facility. More specifically, it can be seen that printing is performed within a printing enclosure chamber 803 such that the environment can be controlled for a week ("controlled environment"); this control is typically performed to exclude unacceptable dust particles, Or otherwise in a particular gas Printing is performed in the presence of a constituent (for example, nitrogen, an inert gas, or the like). In summary, a substrate 813 is generally introduced into the printing press using an environmental buffer chamber (not shown) and transported to a floating support table 815 using a mechanical loader, which also passes through one or more of the substrates. The detection of the reference point (the reference point for detecting the position of the precise substrate and a camera or other optical detector not shown in Figure 8A) is properly aligned with the substrate for printing. The printing system is performed using a printhead assembly 807 that moves back and forth along a slider 811 in the direction of a "slow print axis" (as depicted by arrow 809). The printhead assembly 807 is depicted as a single article, but it can be one of a plurality of printheads (e.g., 6, 10, or other number) of complex components, each having hundreds to thousands of printing nozzles (e.g., There are two thousand nozzles each). The printhead assembly 807 deposits a liquid ink at a precise location on the substrate 813 to a precise thickness, where the ink comprises a material that will form a permanent stack of one or more products intended to be fabricated on the substrate 813. . For example, the material can be an organic or inorganic material, a conductor or insulator, a plastic, a metal, or some other type of material. In a typical application, the substrate 813 is more than one meter wide and several meters long and is used to simultaneously fabricate a plurality of OLED displays arranged in an array on a substrate; each stack is deposited across all such "children" One of the integrated printing processes of the panel "(ie, across such displays in multiple manufacturing), where individual displays are ultimately cut from the substrate by other procedures. Each printing process can deposit a different ink to a particular thickness, for example, conductors, insulators, illuminating elements, semiconductor materials, encapsulation, etc., using printing instructions specific to a particular stack. In an assembly line process, it can exist in multiple presses, in different locations or in successive different deposition processes. For OLED materials, an ink is deposited for a particular stack, and after deposition, the substrate is removed from the chamber and advanced into a curing chamber (not shown) where the deposited ink can be cured and dried. Heated or The person is treated in other ways to apply durability to the deposited material. Please note that the depicted configuration represents a "separate axis" printer, meaning that the floating table 815 and associated loader (not shown) are seen along one of the dimensions near the lower right corner of the figure. In the direction of the Y-axis 825, the substrate is pushed into and out of the drawing page.

To perform the droplet measurement, the printhead assembly 807 is selectively advanced outside of a normal printing area to a point where it can be parked in a service station, generally associated with a second Enclosed environment 805. This second environment is optional, but facilitates inspection, printhead replacement, and other forms of inspection without the need to add venting holes to the printing enclosure 803. To park the printhead assembly 807, the assembly is moved to a position that appears generally at the left side of the figure and is then advanced vertically to seal the printhead assembly 807 to a chamber that serves as the second enclosed environment. As depicted by the dashed line position 819. Within this "parking" position, the drop measurement system 817 can be controlled (e.g., in three dimensions) to selectively move a measurement area, simulating a substrate deposition height adjacent to any desired nozzle area.

Note that, as previously mentioned, in a typical application, it is desirable to maintain the manufacturing equipment 801 as "online" and in use as possible. To this end, it is not performed when the device 801 can be used for printing (and for product manufacturing), in one embodiment, the measurement and printing are "ping-pong alternate", meaning that The next substrate (eg, 813) is loaded or unloaded, and during a time interval of the printing action, the printhead assembly 807 is advanced to the service station and partially calibrated (eg, for print nozzles and/or print nozzles) One of the waveforms is scrolled through the subset) to establish a robust set of measurements, update to the latest state, and overhaul for the first nozzle in a manner that accumulates the total number of statistical measurements, as previously described. Please note that any of these features may be considered selective and is not necessary to disclose the implementation of the technology.

Figure 8B provides a plan view of the substrate and printer taken along line B-B of Figure 8A during the deposition process. The printed enclosed chamber is likewise generally indicated by reference numeral 803, while the second enclosed environment for droplet measurement is generally designated by reference numeral 805. Within the printing enclosure, the substrate on which the substrate is to be printed is generally designated by the numeral 813, and the support table for transporting the substrate is generally designated by the numeral 815. In summary, any xy coordinate of the substrate is reached by a combination of movements, including movement of the substrate by the x and y dimensions of the support table (eg, using a floating support, as indicated by reference numeral 857), and utilizing Movement of the "slow axis" x dimension of one or more printheads 807 of slide bar 811 is generally indicated by arrow 809. As previously mentioned, the floating stage and substrate handling infrastructure is used to move the substrate along one or more "fast axes" as needed during printing. It can be seen that the print head has a plurality of nozzles 865, each of which is controlled by a hair styling guided from one of the printed images (for example, when the print head is along the "slow axis" from left to right and from right to When moving to the left, it causes printing corresponding to the line of the grid point of the printing machine; please note that although only some printing nozzles are depicted in the figure, in fact, it contains hundreds to thousands of such nozzles, configured Many rows and columns. With the relative movement between one or more print heads and the substrate provided in the direction of the fast axis (i.e., the y-axis), the printing essentially presents a strip-shaped area of a plurality of individual columns following the grid points of the printer. It is also possible to selectively rotate or otherwise adjust the printhead assembly to change the effective nozzle spacing, reference numeral 867. Note that a plurality of such print heads can be used together and adjust the x dimension, y dimension, and/or z dimension offset relative to each other as desired (see the axial legend in Figure 8B). The printing action continues until the entire target area (and any border areas) has been printed with ink as needed, with the vertical component of the depicted transfer direction 857 representing the relative printhead assembly/substrate movement. After the deposition of the necessary amount of ink, the substrate is completed, such as by using a liquid layer from the liquid ink to form a permanent laminate External (UV) or other curing or hardening procedures. As described earlier, when the substrate is loaded or unloaded for printing, the printhead is advanced to a service station and sealed to a second enclosed environment 805. In practice, this second enclosed environment is configured to print a subset of the closed chambers 803 as previously described such that it can replace a printhead without having to add venting holes to the printed enclosure. Within the second enclosed environment 805, the drop measurement system 817 (which can be seen in the dashed line below the slide bar 811) is selectively engaged (again, advantageously utilizing, for example, the entirety of the drop measurement system of one of the chassis) Sexual three-dimensional links) for measurement as described earlier.

Figure 9 provides a graph illustrating one of a plurality of nozzles for measuring the droplet position relative to the desired position of the droplet. More specifically, the chart is generally indicated by reference numeral 901 and displays a group of approximately 40 nozzles. It should be assumed that chart 901 represents image data, for example, as described above with reference to Figures 6A through 6C, to obtain a drop position relative to one of the corresponding expected positions (i.e., such as position 904). That is, such as location 903). With respect to Figure 9, it should be noted that some features. First, the nozzles appear to be arranged in a slightly staggered array of nozzles, as shown by icon 905; this feature allows for extremely precise drop spacing, for example, when manufacturing tolerances cause the nozzle to be positioned at a span of hundreds of microns apart A slight staggering between columns and columns in the scan direction allows for the use of alternating nozzles (e.g., nozzles corresponding to positions 906 corresponding to nozzles at position 907), which allows for extremely tight droplet placement, for example, Within 20 microns or less of any predetermined location on a substrate. Second, the chart 901 indirectly emphasizes the benefits provided by the position measurement of the drop measurement system relative to a print head, for example, the system knows exactly which nozzle corresponds to position 903 and the expected position 904 shows its importance to Ability to match any measurement (and any nozzle qualification verification or adjustment) to the correct nozzle. Through image processing, it can determine the precise positional offset of each nozzle and is included in the nozzle verification and printing schedule. factor. Finally, please note again that the use of a transparent film not only allows image capture of the deposited droplets, but also allows for image capture of the nozzle (eg, through the film of the transparent film), which facilitates the performance of the distance analysis by the software. This is not necessary for all embodiments. For example, how the image transmitted through the film corresponds to the position of the nozzle plate, the software can easily infer the position of the nozzle relative to the captured image, and calculate the positional offset based on this. . In the context of Figure 9, reference numeral 904 represents an image nozzle position in one embodiment, wherein any deviation between measurement position 903 and position 904 represents droplet velocity and/or warpage. Also, although Figure 9 represents the drop position offset relative to the desired drop position, a similar analysis can be used to measure the drop volume, for example, by the drop color (eg, gray scale value) ), the diameter of the droplet, or other features of the captured image are compared to a standard from which the droplet volume is calculated. Through the use of repeated additional measurements of each nozzle or nozzle-waveform pairing, the system can easily establish any desired distribution of droplet parameters based on the basis of each nozzle or per nozzle waveform.

Figure 10 shows a flow chart 1001 in which the drop volume is determined from a captured image. Referring to numeral 1003, one of the droplets generated by a nozzle array is first imaged from the memory. This image is then filtered as appropriate to just segment the droplet of interest (e.g., with a different color intensity depending on the thickness or concentration of the ink on the deposition medium), reference numeral 1005. Note that such filtered images may be one of the first, second, third or other examples of the filtering action performed to measure a particular parameter from a single image (eg, other samples may be used for droplet velocity) , position, nozzle position, etc. calculate distance, position, offset, etc.). Referring to numeral 1007, any color hue is then processed to correlate the hue to ink thickness or density; for example, if the deposited ink has a slightly reddish color, a "redder" portion of the image will typically represent a greater thickness. . Note that for an embodiment in which multiple droplets are deposited at a time from each nozzle, There may be multiple visible droplet overlaps, and the thickness treatment 1007 takes this into account in the preferred embodiment, segmenting out any individual droplets; however, this is not necessary for all embodiments, for example, If it is known that, for example, five droplets have been deposited, it may be sufficient to calculate the overall volume and divide by five. Referring to reference numeral 1009, the droplet radius is then calculated (or pooled ink coverage) as described earlier and used in conjunction with the derived thickness magnitude to calculate the total deposited ink. It is important that the transparent film used as a deposition surface ideally holds the deposition ink and thus may be different from one of the actual deposition surfaces used in actual printing (eg, a glass substrate); thus, as indicated by reference numeral 1008 Depicting, one of the storage criteria specific to the deposited material is drawn and used in conjunction with thickness processing, volume calculation 1011, or both to obtain the correct droplet volume estimate. Finally, the measurement data is stored, reference numeral 1013, and any calculated distribution of each nozzle or nozzle waveform (e.g., average and degree) is updated for use in printing or scanning planning. Note that a similar comparison of a standard and raw value (or offset) calculation can be applied to many other parameters outside of the volume, depending on the suitability of the particular application.

From the various techniques and considerations mentioned above, a process can be implemented to rapidly mass produce products with low system cost. By providing fast repeatable printing techniques, it is believed that printing can be substantially improved, for example, by reducing the layer-by-layer printing time to a fraction of the time required before the aforementioned techniques are employed. Returning to the example of a large HDTV display, each color component stack of a large substrate (for example, a 8.5-generation substrate, approximately 220 cm x 250 cm) can be accurately and reliably printed in one hundred and eighty seconds or Within a shorter period of time, or even ninety seconds or less, represents a substantial process improvement. Improving the efficiency and quality of printing paves the way for the huge cost reduction of large HD TV displays, resulting in lower end-user costs. As previously stated, display manufacturing (particularly OLED manufacturing) is described herein. An application of the technology that can be applied to a large number of processes, computers, printers, software, manufacturing equipment, and terminal devices, and is not limited to display panels.

The use of specific terminology and schema symbols in the <RTI ID=0.0> </ RTI> <RTIgt; </ RTI> <RTIgt; In some instances, such terms and symbols may imply specific details that are not essential to the practice of the embodiments. The terms "exemplary" and "embodiment" are used to denote an example and are not a preferred or required item.

As previously indicated, various modifications and changes can be made to the embodiments disclosed herein without departing from the broader spirit and scope of the disclosure. For example, features or characteristics of any embodiment can be applied in combination with any other embodiment, at least where practicable, or in place of its equivalent features or features. Thus, for example, not all features may be shown in each of the drawings. For example, one of the features or techniques shown in accordance with the embodiments of the drawings should be construed as being One of the elements of the formula or embodiment, or a combination thereof, is not specifically indicated in the specification. Accordingly, the specification and drawings are to be construed as illustrative and not limiting.

101‧‧‧ Flowchart

103-123‧‧‧Steps

Claims (27)

A system for measuring parameters associated with droplets ejected by a plurality of nozzles of a printhead, the system comprising: a film having a first side and a second side, the first side being positioned for the printing Near the head, a substrate is provided to receive ink droplets from the plurality of nozzles; an image capture subsystem is positioned to capture an image through the second side of the film, the image representing nozzles received at respective locations of the nozzles Ink droplets, the image capture subsystem is configured to generate an output signal to deliver the captured image to an image processing system; and a mechanism for advancing the film to position the film for a subsequent image capture program In part, wherein droplets from a plurality of nozzles of the printhead are received over the first side of the film, the advancement of the film does not require repositioning of the printhead or the image capture subsystem. The system of claim 1, wherein the system further comprises the image processing system, the image processing system having at least one processor and a plurality of instructions stored on the processor readable medium, wherein the plurality of instructions are executed And causing the at least one processor to receive the captured image from the image capturing subsystem to store the captured image in the processor-accessible memory to process the captured image to represent one or more deposited droplets The respective identification image data is associated with the respective nozzles, and the parameters of the one of the plurality of nozzles are calculated by processing a set of identification image data, and the parameters of the one of the respective nozzles are stored in the processor and can be stored. Take the memory. A system of claim 2, wherein the parameter comprises an average of one of the droplets produced by the respective nozzle. A system as claimed in claim 2, wherein the parameter comprises a statistical measure of the droplets produced by the respective nozzles. A system of claim 2, wherein the parameter comprises an expected volume of one of the droplets produced by the respective nozzle. A system of claim 5, wherein the expected volume is expressed as a unit of resolution that is less than one picoliter. A system as claimed in claim 2, wherein the parameter comprises one of the expected droplet trajectories of the droplets produced by the respective nozzles. The system of claim 1, wherein the film comprises a colorless, transparent film strip, and wherein, further, the film is implemented as one of the colorless, transparent film strip supply roll and the colorless, transparent film strip One of the portions receives the reel in the form of a drop once it has been deposited, and wherein the mechanism includes a motor to advance the receiving reel immediately after image capture. The system of claim 8 wherein the mechanism further comprises a suction mechanism for carrying the colorless, transparent film when the droplets are printed on the first side of the colorless, transparent film strip. The second side is adhered to a platform. The system of claim 1, wherein the ink comprises a monomer and wherein the mechanism further comprises a curing mechanism to solidify the droplet into a hardened substance after deposition on the first side. The system of claim 10, wherein the system selectively activates the curing mechanism after the deposition of the droplets, but before the image capturing of the image capturing subsystem, such that the captured image represents that the image has been hardened. Droplets on the first side of the film. The system of claim 10, wherein the curing mechanism comprises an ultraviolet light source that, when activated, is configured to transform the monomer into a polymer. For example, the system of claim 1 includes a chassis and a control subsystem, The chassis is configured to carry the image capturing subsystem, the mechanism and the control subsystem, and the control subsystem is configured to electronically control the actuation of the mechanism and the image capturing of the image capturing subsystem, each of which is based on Electronic, external instructions. The system of claim 1 is implemented in a printing press for receiving a series of substrates and printing the ink on each of the substrates in the series using the printing head, the printing machine Having a service station configured to intermittently transport the print head to a docking station located in the service station, the system including a moving mechanism relative to the print head and relative to the printing One of the chassis moves the system to reposition the film relative to the parked position when the printhead is in the parked position in the service station. A system of claim 14, wherein the moving mechanism is to move the system in three dimensions relative to the printhead located at the docking position. The system of claim 1, wherein the image capture subsystem comprises a high resolution, high speed digital camera and an electronically actuated focus for adjusting the focus of the image captured by the high resolution, high speed digital camera. mechanism. A method of measuring a parameter associated with a droplet ejected by a plurality of nozzles of a printhead, the method comprising: providing a film having a first side and a second side, and positioning the first side to the print head Providing a substrate for receiving ink droplets from the plurality of nozzles; and using an image capturing device to capture an image through the second side of the film, the image representing ink droplets received from nozzles located at respective positions of the nozzle, And correspondingly generating an output signal to deliver the captured image to an image processing system; and advancing the film to position a new portion of the film for a subsequent image capture program, Droplets from the plurality of nozzles of the printhead are received over the first side of the film in a manner that does not require the printhead or the image capture device to be repositioned. The method of claim 17, further comprising receiving the captured image by using an image processing system, storing the captured image in a processor-accessible memory, processing the captured image to represent one or more deposition solutions The individual identification image data of the drop is associated with each nozzle, the processing of a set of identification image data, the calculation of the parameters of the one of the plurality of nozzles, and the storage of the parameters of the respective ones of the respective nozzles are stored in the processor. Access memory. The method of claim 18, wherein the parameter comprises an average of one of the droplets produced by the respective nozzles. The method of claim 18, wherein the parameter comprises a statistical measure of the droplets produced by the respective nozzles. The method of claim 18, wherein the parameter comprises an expected volume of one of the droplets produced by the respective nozzle. The method of claim 21, wherein the expected volume is expressed as a unit of resolution that is finer than one picoliter. The method of claim 18, wherein the parameter comprises one of the expected droplet trajectories of the droplets produced by the respective nozzles. The method of claim 17, wherein the film comprises a colorless, transparent film strip, and wherein the film is further embodied as a colorless, transparent film strip supply roll and the colorless, transparent film strip One of the portions is in the form of a reel, once a drop has been deposited thereon, and wherein the method further comprises using a motor to advance the receiving reel immediately after image capture. A device that contains: a printing machine for receiving a first substrate, the printing machine having a printing head, the printing head comprising a plurality of nozzles for ejecting an ink onto the first substrate, the ink comprising a liquid The liquid will be hardened on the first substrate to form a permanent laminate of an electronic device thereon, the permanent laminate of the electronic device having a thickness; and a system for measuring a parameter, The parameter is associated with droplets ejected by the plurality of nozzles of the printhead, the system comprising: a film having a first side and a second side, the first side being positioned adjacent the print head to provide a second substrate receives ink droplets from the plurality of nozzles; an image capture subsystem positioned to capture an image through the second side of the film, the image representing ink liquid received from nozzles located at respective locations of the nozzle Dropping, the image capturing subsystem is configured to generate an output signal to deliver the captured image to an image processing system; and a mechanism for advancing the film to locate a subsequent image capturing program One droplet new film portion, wherein from the plurality of nozzles of the print head is received over the first surface of the film, the film does not need to advance the print head or the repositioning of the image capturing subsystem. The apparatus of claim 25, further comprising a hood for enclosing the printer and the system within a controlled environment. The apparatus of claim 25, wherein the printing machine is configured to continuously print the ink on each of a series of the first substrates, and wherein the apparatus further comprises a mobile system and an image processing system, The mobile system advances the printhead to a measurement position between printing on a continuous substrate in the series, the image processing system having at least one processor and stored in The processor can read a plurality of instructions on the medium, and when the plurality of instructions are executed, causing the at least one processor to receive the captured image from the image capturing subsystem to store the captured image in the processor-accessible memory Processing the captured image to associate respective identification image data representing one or more deposited droplets with respective nozzles to process a set of identification image data to calculate a parameter of the one of the plurality of nozzles, The parameters of the respective ones of the respective nozzles are stored in the processor-accessible memory.