JP2009030977A - System for droplet observation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system capable of measuring accurately a contact angle of a droplet discharged from an ink jet head and impacted onto a substrate. <P>SOLUTION: This observation system 1 has the ink jet head 30; the first observation unit 10 including the first imaging device 11 for observing the flying state of the droplet discharged from a nozzle 31 of the ink jet head, and the first imaging lens 12; the second observation unit 20 including the second imaging device 21 for observing from the side, a state after the droplet discharged from the nozzle 31 of the ink jet head is impacted onto the target substrate 2, and the second imaging lens 22; and a head moving mechanism 50 for moving the ink jet head 30 along the first line X1 connecting a focal position 13 of the first imaging lens 12 to a focal position 23 of the second imaging lens 22. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a system capable of observing a state in which droplets ejected from an inkjet head have jumped and landed.

  The ink jet technology is a technology capable of landing a precise droplet on a demand on a precise position without contact with a micro droplet having a diameter of several tens of micrometers. Therefore, for example, it is used for the purpose of causing a droplet to land accurately on a target position on a substrate having a water repellent surface and a hydrophilic surface separately applied, such as a black matrix.

  In this case, observing the shape of the droplet that has landed at the target position and how the contact angle changes with time is a very important factor in material development. . Conventionally, a method of dripping a liquid from a capillary is mainly used for measuring a contact angle when a target liquid is landed on the target substrate. However, since the amount of liquid dropped from the capillary varies, reproducibility cannot be obtained. The amount of liquid dropped from the capillary is on the order of μ liters, whereas the amount discharged from the inkjet nozzle is on the order of several to several tens of liters. Therefore, the ratio of the surface area of the liquid is completely different from that of the liquid dropped from the capillary. For this reason, the results may differ greatly from changes over time in the contact angle when the liquid is actually ejected from the inkjet nozzle, such as the drying speed of the liquid and the drying process. Furthermore, the capillary has a problem that it is difficult to specify the exact position and land the liquid.

Patent Document 1 discloses an apparatus that can obtain a highly reliable measurement result for the discharge amount of a very small amount of functional liquid droplets discharged from each nozzle of an inkjet head. This measuring apparatus is an image analysis means for analyzing the diameter of a functional droplet using a two-dimensional image of the functional droplet landed on an inspection substrate that has been surface-treated so that the landed functional droplet has a predetermined contact angle. And a calculating means for calculating the volume of the functional droplet based on a predetermined contact angle and the diameter of the functional droplet. Specifically, the functional liquid droplet ejection head faces the inspection substrate, and functional liquid droplets are ejected from the three nozzles to the inspection substrate, respectively. Next, the inspection substrate on which the three functional liquid droplets to be imaged have landed is moved below the imaging camera by the moving table, and the imaging camera is moved to the three functional liquid droplets by the camera moving table. Move down. Then, three functional liquid droplets that are substantially hemispherical with a predetermined contact angle on the inspection substrate are imaged by the imaging camera.
JP 2005-119139 A

  The state of a minute droplet having a diameter of about several tens of μm may greatly change in a short time after being ejected. In addition, a lens system with a high magnification is required to capture such a fine droplet in order to obtain an image that can measure the contact angle. The depth of focus of a high magnification lens system is narrow. Therefore, if the apparatus moves the inspection substrate to the imaging camera after discharging the droplet onto the inspection substrate, the state is already in the stage when the droplet enters the focusing range of the lens of the imaging camera. It may have changed, and the state immediately after the target hits cannot be observed.

  It is also important to observe the state in which the droplets are ejected from the nozzles of the inkjet head when observing the state where the droplets ejected from the nozzles of the inkjet head have landed on the target. For example, a droplet discharged into the air from a nozzle of an inkjet head is not a single round particle, but a columnar liquid having a certain length of “liquid column” is formed on the nozzle surface. In the process of flying in the air, the liquid column may reach the target while being separated into a leading main droplet and a plurality of satellite droplets after the main droplet due to the surface tension and air resistance of the liquid itself. Therefore, when the focal depth of the imaging lens is narrow, the droplets that enter the focusing range of the lens are not necessarily all droplets of the inkjet head.

  There is a demand for a system capable of observing fine droplets ejected from an inkjet head including the above-described conditions.

  One aspect of the present invention is an inkjet head, a first observation unit including a first imaging device and a first imaging lens for observing a flying state of a droplet discharged from a nozzle of the inkjet head, A second observation unit including a second imaging device and a second imaging lens for observing a state after a droplet discharged from a nozzle of an inkjet head has landed on a target from the side; And a head moving mechanism that moves the inkjet head along a first line connecting the focal position of the imaging lens and the focal position of the second imaging lens. The first imaging lens and the second imaging lens may be a lens system including a plurality of lenses.

  This system has a first observation unit for observing the flying state and a second observation unit for observing the landing state, and the focal position of the first imaging lens and the second imaging by the head moving mechanism. The inkjet head is moved along a first line connecting the focal positions of the lenses for use. Inkjet technology is not limited to the main droplets ejected from the nozzles of the inkjet head, but also in the satellite droplets separated from the main droplets, if the physical properties of the liquid and the driving conditions on the inkjet head side are controlled to be constant. The reproducibility is very high. Therefore, if there is no time difference enough to change the surrounding conditions such as temperature, even if the observation of the flying state and the observation of the landing state are performed at different timings, it is almost equivalent to observing the same droplet. .

  In this system, the ink jet head is set by the head moving mechanism so that the liquid droplet ejected from the nozzle passes through the focal position of the first imaging lens, and the first liquid droplet is ejected. The flying state of the droplet can be observed by the observation unit. After that, the ink jet head is set by the head moving mechanism so that the liquid droplet ejected from the nozzle lands on the target at the focal position of the second imaging lens, and the second liquid is ejected by ejecting the liquid droplet. The state of the landed droplet can be observed by the second observation unit from the stage where the droplet discharged from the nozzle has landed on the target by the observation unit. Although depending on the temporal resolution and recording ability of the second observation unit and the recording apparatus associated therewith, the second observation unit can also observe the state immediately before and after the droplets land on the target.

  In this system, the observation of the flying state and the observation of the landing state are performed by different units, so that it is possible to observe with a unit having a configuration suitable for observation of each state including the imaging lens. Further, by adjusting the focal position of the first imaging lens and the focal position of the second imaging lens in advance, it is possible to adjust the focus each time only by moving the inkjet head by the head moving mechanism, and Save time and observe the flying and landing states with clear, focused images.

  This system desirably further includes a target moving mechanism for moving the target in three dimensions in front of the second imaging lens. In this system, the position of the inkjet head is controlled so that the liquid droplets land on the focal position of the second imaging lens. Therefore, if droplets are to be landed at different positions on the target, it is necessary to move the target, not the inkjet head. Furthermore, if the contact angle that has landed on the target is to be observed accurately, it is desirable that the position of the target can be controlled so that the surface of the target is in the vicinity of the optical axis of the second imaging lens. Therefore, a target moving mechanism that moves the target in three dimensions in front of the second imaging lens is useful.

  In this system, the first observation unit and the second observation unit are arranged so that the optical axis of the first imaging lens and the optical axis of the second imaging lens are orthogonal to each other, and the first line is It is preferable to arrange the second imaging lens so as to coincide with the optical axis. It is desirable that the first imaging lens and the second imaging lens can finely adjust their positions in the three-dimensional direction in order to finely adjust their focal positions. Therefore, it is desirable to arrange each imaging lens at a position where the user can easily access. Furthermore, it is necessary to secure a space for the user to access in order to set the target in front of the second imaging lens. By disposing the first observation unit and the second observation unit so that the optical axis of the first imaging lens and the optical axis of the second imaging lens are orthogonal to each other, A space for access from the same direction as the first imaging lens can be secured ahead. Furthermore, it can arrange | position so that the 1st line which moves an inkjet head may correspond with the optical axis of the 2nd imaging lens. For this reason, the position of the inkjet head can be controlled by the head moving mechanism so that the focal position and the landing position of the second imaging lens having a higher magnification and a narrow focal depth coincide with each other with high accuracy.

  Further, in this system, since the inkjet head moves along the focal position where each imaging lens images, the head moving mechanism can move the illumination for imaging together with the inkjet head.

  In this system, the head moving mechanism moves the inkjet head to the landing position. For this reason, the imaging unit for confirming the landing position can be moved together with the inkjet head by the head moving mechanism, and the landing position on the target can be accurately confirmed by the imaging unit that can magnify the target.

  FIG. 1 shows a schematic configuration of an observation system according to an embodiment of the present invention. The observation system 1 includes an inkjet head 30, a first observation unit 10 for observing a flying state of a droplet ejected from a nozzle 31 of the inkjet head 30, and a liquid ejected from the nozzle 31 of the inkjet head 30. A second observation unit 20 for observing a state after the droplet has landed on the target substrate 2 and a head moving mechanism 50 for moving the inkjet head 30 in the X direction are included. The first observation unit 10 includes a first imaging device 11 and a first imaging lens 12 for observing the flying state of droplets ejected from the nozzles 31 of the inkjet head 30. The second observation unit 20 includes a second imaging device 21 and a second imaging unit for observing a state after a droplet discharged from the nozzle 31 of the inkjet head 30 has landed on the target substrate 2 from the side. Lens 22 for use. Therefore, this observation system 1 is a system suitable for measuring the contact angle of a droplet landed on a target. The head moving mechanism 50 moves the inkjet head 30 along a first line X 1 that connects the focal position 13 of the first imaging lens 12 and the focal position 23 of the second imaging lens 22.

  The head moving mechanism 50 includes an ink jet head 30 and includes a carriage 51 that moves in the X-axis direction and an actuator 52 that moves the carriage 51 in the X-axis direction. In addition to the inkjet head 30, an illumination lamp 25 and an imaging unit 36 are mounted on the carriage 51. The illumination lamp 25 moves with the inkjet head 30 and is disposed so as to face the second imaging lens 22 at the focal position 23. Therefore, the illumination lamp 25 is used as a light source when the second imaging device 21 images the droplet after landing.

  The imaging unit 36 moves together with the inkjet head 30, and the imaging lens 36a is arranged so as to look in the same direction as the nozzle 31 of the inkjet head 30, that is, below the Z axis. For this reason, the imaging unit 36 is moved to an appropriate position by the head moving mechanism 50, and a place where the droplet is landed by the nozzle 31 of the inkjet head 30 on the target substrate 2, that is, the second imaging lens 22. By imaging the focal position 23, the landing position can be determined with high accuracy.

  The carriage 51 is equipped with an actuator 53 that moves the inkjet head 30 in the Z direction. For this reason, the distance between the nozzle 31 of the inkjet head 30 and the target substrate 2 can be controlled.

  The observation system 1 further includes a target moving mechanism 60 that moves the target substrate 2 in three dimensions (X, Y, and Z directions) in front of the second imaging lens 22. The landing position on the substrate 2 can be controlled by moving the substrate 2 in the X direction and / or the Y direction. That is, the position at which the droplets are ejected by the nozzle 31 of the inkjet head 30 is limited to the focal position 23 of the second imaging lens 22, but the substrate 2 is moved by the target moving mechanism 60. A droplet can be landed at a desired location. Further, by moving the substrate 2 in the Z direction, the surface (the height of the surface) of the substrate 2 can be set at the focal position of the second imaging lens 22, and the droplets landed on the surface of the substrate 2. Can be taken clearly from the side.

  In the observation system 1, the first line X 1 that connects the focal position 13 of the first imaging lens 12 and the focal position 23 of the second imaging lens 22 is further connected to the second imaging lens 22. It coincides with the optical axis L2. The first line X1 (optical axis L2) is orthogonal to the optical axis L1 of the first imaging lens 12. With such a layout, a relatively wide space can be secured in front of the second imaging lens 22, and the work of setting the substrate 2 on the target moving mechanism 60 is facilitated. Further, in order to acquire an image for measuring the contact angle, the second imaging lens 22 has a high magnification and the depth of focus is narrowed, but the movement of the head moving mechanism 50 in the X direction is changed from the landing position of the droplet to the first position. This can be used to match the focal position 23 of the second imaging lens 22.

  The observation system 1 can be configured using a robot module 5 having an X axis, a Y axis, and a Z axis. The X-axis unit of the robot module 5 includes a head carriage 51 and an imaging unit 36 for designating a landing position as a head moving mechanism 50. The imaging unit 36 includes a CCD camera 36b and a lens 36a. The Y-axis unit of the robot module 5 mounts the substrate 2 to be landed as the target moving mechanism 60. The Z-axis unit 53 of the robot module 5 sets a working distance between the substrate 2 and the nozzle 31 of the inkjet head 30. The Y-axis unit 60 moves a table 65 for mounting the substrate 2 in the Y direction, and the table 65 contains an actuator that can finely adjust the position of the table in the X-axis direction and the Z-axis direction.

  An imaging device 11 and a lens system 12 of the first observation unit 10 are attached to the robot module 5 by a table 19 that can finely adjust their positions in the X, Y, and Z directions. Therefore, the position of the lens system 12 can be finely adjusted in advance so that the droplets discharged from the nozzles 31 of the inkjet head 30 moved by the head moving mechanism 50 pass through the focal position 13. In this system 1, an illumination lamp 15 is disposed on the opposite side of the lens system 12 along the optical axis L <b> 1, and a state in which the droplets fly can be imaged by turning on the illumination lamp 15.

  In addition, an imaging device 21 and a lens system 22 of the second observation unit 20 are attached to the robot module 5 by a table 29 that can finely adjust their positions in the X, Y, and Z directions. Therefore, the position of the lens system 22 can be finely adjusted in advance so that the liquid droplets ejected from the nozzles 31 of the inkjet head 30 moved by the head moving mechanism 50 land on the focal position 23. Accordingly, it is possible to accurately determine the relative positional relationship between each part of the inkjet head 30 and the second observation unit 20 for observing the contact angle, so that the droplets are placed on the target substrate 2. It is possible to land on the target position above the image, capture the image with the PC 75, and measure the contact angle.

  The observation system 1 also includes an inkjet head controller (inkjet head control module) 71 that sets the drive conditions of the inkjet head 30, a controller (robot control module) 72 that controls the robot module, and an image processing unit for capturing an image. (Image acquisition module) 73 and a personal computer (PC) 75 for controlling these modules 71 to 73 via an application. Then, by a high-speed camera system including the high-magnification lens system 22 of the second observation unit 20 and the imaging device 21, a droplet landing on the substrate 2 is observed from the side surface of the substrate 2, and the contact angle is measured by the PC 75. The contact angle of the captured droplet image is measured by the application for

  One of the other applications running on the PC 75 is “observation unit—inkjet head correction function”. This application program is operated when the user changes the magnification of the lens system of each of the observation units 10 and 20 when the user newly attaches or replaces the inkjet head 30 to the observation system 1. In the observation system 1, droplets are actually ejected from the inkjet head 30, images of the respective observation units 10 and 20 are displayed on a PC monitor or a television monitor, the droplets are confirmed, and an accurate positional relationship is data. First of all, the correction work for ensuring the above is carried out. Further, while observing the droplet dropped on the substrate 2 on the monitor, the axis of the second observation unit 20 is adjusted by the table 29, and the dropped droplet is displayed just in the center of the monitor screen. Like that. By using a zoom lens as the first imaging lens 12 and / or the second imaging lens 22, it is easy to change the magnification. The setting (correction) performed once here does not require readjustment even if the power supply is logically cut off unless the inkjet head 30 is removed from the system 1.

  Yet another application that runs on the PC 75 is the “landing position determination function”. An image from the imaging unit 36 that moves together with the head 30 is displayed on a PC monitor or a television monitor, and a point at which a droplet is to land on the substrate 2 is designated on the application. Thereafter, the application moves the head 30 so as to land at a designated position, and drops a designated number of droplets at the landing point. The table 65 mounted on the target moving mechanism 60 is movable in the X and Y directions, and the target landing position of the substrate 2 arranged on the table 65 is displayed on the monitor while displaying an image obtained from the imaging unit 36. It can be determined by the PC 75 or the robot controller 72. Since the head 30 is set to discharge at the focal position 23 of the second imaging lens 22, once the ejection position is set by the head correction mechanism, the positional relationship with the second imaging lens 22. Is always immutable. Therefore, the landing position is controlled by moving the substrate 2 by the target moving mechanism 60.

  As shown in FIG. 2, first, the flying state of the liquid droplets discharged from the nozzles 31 of the inkjet head 30 is observed by the first observation unit 10. In inkjet technology, observation of the flying state of a droplet is a very important factor. Since one observation system 1 has an inkjet droplet observation function (first observation unit) 10, the head drive parameters relating to various measurement liquids ejected as droplets from the inkjet head 30 can be measured on the same apparatus. Optimize while observing. Further, in the second observation unit 20, it can be confirmed that liquid droplets are being ejected from the inkjet head 30 in accordance with the driving conditions optimized in advance immediately before or after the contact angle measurement. For this reason, the reliability of the observation result / measurement result (phenomenon / physical property value / change state, etc.) regarding the droplet observed or measured in the observation system 1 can be remarkably improved.

  Even with the same ink jet head, if the physical property values of the liquid are slightly different, stable ejection may not be possible under the same head driving conditions. Therefore, in order to perform contact angle measurement with respect to various liquid materials in the second observation unit 20, it is essential to optimize the head drive parameters in the inkjet head controller 71. If the drive parameters are not optimized, liquid cannot be discharged from the nozzle, or even if it can, only data with very low reproducibility can be collected by the second observation unit 20. Further, when stable ejection cannot be performed, ejection from the nozzle 31 becomes unstable, the liquid droplets fly and bend, the liquid droplets cannot land at the preset focal position 23, and the contact angle cannot be measured. There is also. In this observation system 1, the first observation unit 10 observes the discharge and flight states of the droplets, and the discharge conditions that change for each liquid type can be optimized in the observation system 1.

  On the other hand, the ink jet technology is a technology capable of generating highly reproducible droplets. There is almost no discharge variation for every one. Therefore, by using the first observation unit 10 to grasp in advance the amount of liquid discharged per drop, the second observation unit 20 is landed on the target contact angle measurement position. The number of ejections of liquid can be set arbitrarily. For this reason, the second observation unit 20 can measure various volume contact angles for various liquids. In the observation system 1, the liquid that can be ejected from the nozzle 31 of the inkjet head 30 includes all liquids that can be ejected by the inkjet technique. Typical liquids are various printing inks, analytical reagents, and resins for constituting the microstructure.

  When the discharge condition and the flight condition of the droplet to be observed by the second observation unit 20 are determined by the first observation unit 10, the inkjet head 30 is moved along the first line X1 by the head moving mechanism 50. It moves in the direction of the second observation unit 20. In this process, the landing position of the substrate 2 can be set by the imaging unit 36 that moves together with the head 30.

  Further, a refreshing spot before printing is set on the table 65 on which the target substrate 2 is arranged, and the head 30 can be moved while refreshing. The target moving mechanism 60 can arbitrarily set a refreshing position including the target substrate 2. Therefore, in this observation system 1, it is possible to perform refreshing for an arbitrary number of ejections at an arbitrary driving frequency with respect to a specified refreshing spot, and further, from the end of refreshing to the time when droplets are ejected for contact angle measurement. The time can be controlled.

  In the case of the ink jet technology, there is a problem of so-called clogging in which liquid is not ejected due to evaporation of the liquid from the minute nozzle. Therefore, even when droplets are ejected at the target position, it is necessary to perform the discarding (refreshing) from the inkjet head nozzle 31 at a position as close as possible to the target position. Thereby, the measurement of the contact angle can be realized in the second observation unit 20 under more stable conditions. Therefore, in this observation system 1, as shown in FIG. 3, a pre-printing refreshing spot (refreshing area) 66 is arranged on the table 65, and immediately after the refreshing, droplets for measuring the contact angle are ejected. I have to. Further, the position of the refreshing spot is not limited to the area 66, and the refreshing spot can be set on the target substrate 2. Even when the refreshing spot is set very close to the landing position, the focal depth of the second imaging lens 22 is narrow, so that the droplets ejected for refreshing do not enter the imaging range (focusing range). It is easy.

  The level of clogging depends largely on the performance of the liquid. Therefore, it is necessary to optimize the head driving frequency and the ejection number at the time of refreshing according to the liquid to be observed. Further, by making it possible to control the time from the end of refreshing to the start of contact angle measurement, the system 1 can grasp the change in contact angle over time. The refreshing area 66 provided in the table 65 shown in FIG. 3 includes an inclination for storing the liquid, and the refreshing can be repeated.

  In this observation system 1, the inkjet head 30 is disposed on a carriage 51 that is movable in the X-axis direction, and a stage (table) 65 that can be finely adjusted in the XYZ directions on an extension line of the movement axis of the inkjet head 30. The contact angle of the droplet that has been placed and landed on the substrate 2 fixed thereon can be measured by the second observation unit 20. Therefore, the observation system 1 is an ink jet micro droplet contact angle measurement system. In this observation system 1, since the high-magnification lens 22 for projecting a droplet size of about several tens of μm is large and heavy, the second observation for observing the contact angle including the lens 22 is used. The unit 20 is fixed (fine adjustment is possible). As a result, the position where the second imaging lens 22 can capture an image is determined. Therefore, the nozzle 31 of the inkjet head 30 can be moved to the position where the droplet is ejected to the focal position of the second imaging lens 22. The image of the liquid droplet can be acquired immediately before and / or immediately after the liquid droplet has landed.

  Moreover, the positional relationship between the inkjet head 30 and the illumination unit 25 is fixed by arranging the illumination unit 25 as a light source for observing the contact angle together with the inkjet head 30 on the carriage 51. Therefore, the positional relationship between the illumination unit 25 and the second imaging lens 22 for observing the contact angle is automatically determined by determining the positional relationship between the inkjet head 30 and the second imaging lens 22. The work required for adjusting the imaging position can be simplified. Further, by mounting on the carriage 51, interference between the illumination unit 25 and the head 30 and the imaging unit 36 that move together with the carriage 51 and the carriage 51 can be avoided, and the design of the observation system 1 is facilitated.

  FIG. 4 shows a different example of the observation system 1. In this observation system 1, the first observation unit 10 and the second observation unit 20 are arranged in parallel, and the optical axes L1 and L2 are parallel to each other. Also in this observation system 1, the head moving mechanism 50 includes the inkjet head along the first line X <b> 1 that connects the focal position 13 of the first imaging lens 12 and the focal position 23 of the second imaging lens 22. Move 30. In addition, the same code | symbol is attached | subjected about the part which is common in the observation system mentioned above.

  An example of the operation in these observation systems 1 is shown in FIG. This is a case where the head control module 71, the robot control module 72, and the image acquisition module 73 for measuring the contact angle are all operating in a dedicated application.

  If the image acquisition module 73 for measuring the contact angle is not present in this application and is driven by a dedicated application for contact angle measurement, the image acquisition module will accurately indicate when the image capture may start. It is necessary to instruct 73. Therefore, as shown in FIG. 6, the dedicated application for contact angle measurement actually starts moving the head 30 and the table 65 and capturing an image assuming a refreshing time after the user gives a measurement start instruction. It is desirable to have a mode for measuring the time required until the liquid is actually discharged at the target position on the substrate 2 after the user issues a measurement start instruction. . The time required until the liquid is actually ejected at the target position of the substrate 2 after the user issues a measurement start instruction varies depending on the number of droplets of refreshing, the moving distance and speed of the head 30 by the robot module 5. Therefore, it is more preferable to provide a mode in which the movement time to the refreshing position, the refreshing time, the movement time to the target position of the substrate 2 after the refreshing, and the time to discharge can be measured. By providing a mode that individually measures these three operations, if any one of the operation parameters is changed, only the time required for that operation is re-measured, and the waiting time until ejection is newly established. Can be set.

  In the above description, an example is described in which the contact angle of a droplet landed on the target substrate is measured by the observation system. However, the target for measuring the contact angle is not limited to the substrate, and a piece of paper, Any material, such as a piece of cloth, that can be applied or landed with ink droplets by inkjet technology may be used. In addition, since this observation system can acquire an image showing the progress of the liquid droplets ejected from the nozzles of the inkjet head and landed on the target, the physical property values that can be observed not only from the contact angle but also from other images It is possible to observe in detail how the state of the droplet changes.

The figure which shows an example of an observation system. The figure which shows the state which the inkjet head moved to the 1st observation unit in the observation system shown in FIG. The figure which shows the table of a target moving mechanism. The figure which shows a different observation system. The timing chart which shows an example of operation | movement of an observation system. The timing chart which shows the other example of operation | movement of an observation system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Observation system, 2 Target substrate 10 1st observation unit, 11 Imaging device, 12 Imaging lens, 13 Focus position 20 Second observation unit, 21 Imaging device, 22 Imaging lens, 23 Focus position 30 Inkjet head 31 nozzle 50 head moving mechanism, 60 target moving mechanism

Claims (5)

An inkjet head;
A first observation unit including a first imaging device and a first imaging lens for observing a flying state of a droplet discharged from a nozzle of the inkjet head;
A second observation unit including a second imaging device and a second imaging lens for observing a state after a droplet discharged from a nozzle of the inkjet head has landed on a target from the side;
And a head moving mechanism that moves the inkjet head along a first line connecting a focal position of the first imaging lens and a focal position of the second imaging lens.   The system according to claim 1, further comprising a target moving mechanism that moves the target three-dimensionally in front of the second imaging lens.   3. The optical axis of the first imaging lens according to claim 1 or 2, wherein an optical axis of the first imaging lens and an optical axis of the second imaging lens are orthogonal to each other, and the first line is an optical axis of the second imaging lens. Match the system.   4. The system according to claim 1, wherein the head moving mechanism moves illumination for imaging together with the inkjet head. 5.   5. The system according to claim 1, wherein the head moving mechanism moves an imaging unit for confirming a landing position together with the inkjet head.

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