JP2013176714A - Liquid-droplet ejection apparatus and method for detecting ejection state of liquid droplet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique that can highly accurately detect the ejection state of liquid droplets ejected from an ejection port of each nozzle during the execution of application operation.SOLUTION: A liquid-droplet ejection apparatus 1A includes: an ejector 10 that has a plurality of ejection ports for ejecting liquid droplets onto a substrate sheet, conveyed in a given direction, on a conveyor 92; an imaging unit 72 that captures an image by receiving light emitted from a light source 71; and a detection means that detects the ejection state of liquid droplets by using an image obtained by imaging flying liquid droplets, ejected into the light flux made incident to the imaging unit 72, by the imaging unit 72. The imaging unit 72 is arranged at a position, where the shadow of each liquid droplet flying in the light flux does not overlap with another liquid droplet, and on the side of the conveyor 92.

Description

  The present invention relates to a technique for applying droplets to a medium to be applied.

  As a method for applying droplets to a medium to be applied (application target medium), for example, there is a droplet jet method (for example, Patent Document 1). If the droplet jet method is adopted, it becomes possible to efficiently apply the coating liquid to a necessary portion of the medium to be coated.

  In the above-described droplet jet method, a plurality of nozzles for discharging droplets of the coating liquid are provided in the discharge head, but these nozzles are likely to be non-discharge due to clogging or the like. When an abnormal nozzle occurs, the amount of application applied to the medium decreases. For this reason, it is preferable to monitor the occurrence of abnormal nozzles by detecting the discharge state of droplets discharged from the nozzles.

  Patent Document 1 discloses a technique for detecting a discharge state of a droplet from a drop amount of a light amount when the droplet of light emitted from a light source is transmitted as a method for detecting a discharge state of a droplet discharged from a nozzle. Have been described.

JP-A-2005-280351

  However, in the discharge state detection method described in Patent Document 1, since the droplet discharge state is detected based on the amount of drop in the amount of light incident from the same direction as the nozzle arrangement direction, During execution, it has been difficult to accurately detect the discharge state of droplets from each nozzle.

  Therefore, an object of the present invention is to provide a technique capable of accurately detecting the discharge state of a droplet discharged from the discharge port of each nozzle during the execution of a coating operation.

  A first aspect of a droplet discharge device according to the present invention includes a discharge unit having a plurality of discharge ports for discharging droplets to a base sheet on a conveyance band conveyed in a certain direction, a light source, An imaging unit that receives light emitted from the light source and obtains an image; and an image obtained by imaging the flying droplet discharged into a light beam incident on the imaging unit by the imaging unit. And detecting means for detecting the discharge state of the droplets, wherein the imaging means is a position where the shadow of each droplet in flight does not overlap other droplets in the light flux, It is arranged on the side.

  The second aspect of the droplet discharge apparatus according to the present invention is the first aspect, wherein the plurality of discharge ports are arranged in a fixed direction in the discharge unit, and the imaging unit includes the imaging unit It arrange | positions in the diagonal position with respect to the sequence direction of a some discharge outlet.

  A third aspect of the droplet discharge device according to the present invention is the first aspect or the second aspect, wherein the light source and the imaging means are supported in a state of being opposed to each other. The supporting means further includes a first moving mechanism capable of moving the imaging means in a direction perpendicular to the transport direction, and a first mechanism capable of moving the imaging means in the same direction as the transport direction. A second moving mechanism, and a rotational moving mechanism capable of rotating at least one of the first moving mechanism and the second moving mechanism in the same plane.

  A fourth aspect of the droplet discharge apparatus according to the present invention is the third aspect described above, wherein the imaging unit acquires information used for detecting the discharge state before the application operation is performed. Is arranged at a position perpendicular to the arrangement direction of the plurality of discharge ports.

  A fifth aspect of the droplet discharge device according to the present invention includes a discharge unit having a plurality of discharge ports for discharging droplets to a base sheet on a transport band that is transported in a fixed direction, a light source, Two sets of imaging units having an imaging unit that receives light emitted from the light source and acquires an image, and the droplets in flight discharged into each light beam incident on each imaging unit Detecting means for detecting the discharge state of the droplet using each image obtained by imaging by each imaging means, and each of the two sets of the imaging units is in flight in a light beam incident on the imaging means It is a position where the shadow of each droplet does not overlap other droplets, and is disposed on both sides of the transport band.

  A method for detecting a discharge state of a droplet according to the present invention is a method for detecting the discharge state of a droplet discharged from a plurality of discharge ports provided in a droplet discharge unit, and a) emitted from a light source. An image pickup means for receiving the received light to obtain an image, and a step of disposing the shadow of each droplet in flight in the light flux so as not to overlap other droplets and on the side of the transport band; and B) a step of discharging liquid droplets from a plurality of discharge ports to a base sheet on a transport belt that is transported in a certain direction; and c) during flight ejected into a light beam incident on the imaging means And a step of detecting a discharge state of the droplets using an image obtained by imaging the droplets by the imaging means.

  According to the present invention, it is possible to accurately detect the discharge state of the liquid droplets discharged from the discharge ports of each nozzle during the execution of the coating operation.

It is a figure which shows the external appearance structure of the droplet discharge apparatus which concerns on 1st Embodiment. It is a figure which shows the upper side figure and front view of a droplet discharge apparatus. It is a figure which shows the top view, front view, and side view of a droplet discharge apparatus. It is a figure which shows the functional block of a droplet discharge apparatus. It is a flowchart which shows operation | movement of a droplet discharge apparatus. It is a figure which shows the top view and front view of the droplet discharge apparatus which concern on 2nd Embodiment.

  Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

<1. First Embodiment>
[1-1. Appearance configuration and overview]
FIG. 1 is a diagram showing an external configuration of a droplet discharge apparatus 1A according to the first embodiment of the present invention.

  As illustrated in FIG. 1, the droplet discharge device 1 </ b> A includes a coating head 10, an imaging unit 70, and a support mechanism (supporting unit) 80 that supports the imaging unit 70. The droplet discharge device 1A performs an application operation for applying a chemical solution by the application head 10 to a medium (base material sheet) to be applied, which is stuck on a belt-like transport belt 92 transported in a predetermined direction TD.

  In addition, the droplet discharge device 1A captures an image of a droplet in flight (“droplet image”) by photographing the droplet discharged from the coating head 10 by the imaging unit 70 during the execution of the coating operation. Or “flying image”). The acquired droplet image is used to identify an abnormal nozzle that does not discharge droplets from among a plurality of nozzles provided on the coating head 10 that discharge droplets. The droplet image is used to estimate the amount of droplets ejected from the coating head 10.

  Hereinafter, each component of the liquid droplet ejection apparatus 1A will be described in more detail. FIG. 2 shows a top view and a front view of the droplet discharge device 1A. FIG. 3 shows a top view, a front view, and a side view of the droplet discharge device 1A.

  As shown in FIG. 1, the droplet discharge device 1 </ b> A sprays a transport mechanism (not shown) as transport means for transporting a strip-shaped transport band 92 along the horizontal direction, and a chemical solution containing a drug on a base sheet. A coating head 10 for coating, an imaging unit 70 for capturing a droplet image, and a support means 80 for supporting the imaging unit 70. In addition, the droplet discharge apparatus 1A includes an overall control unit 40 that controls each of the above-described components provided in the apparatus.

  The coating head 10 atomizes a chemical solution containing a medicine to generate fine droplets, and sprays the droplets on the upper surface of the substrate sheet conveyed by the conveyance mechanism. Specifically, the coating head 10 has a width equal to the entire width of the transport band 92 and is arranged in a plurality of lines arranged at a predetermined pitch along a direction perpendicular to the transport direction TD (the width direction of the transport band 92). A nozzle 11 (see FIG. 2) is provided. The overall control unit 40 (specifically, a coating operation control unit 45 described later) controls the voltage applied to each nozzle 11 to control the ejection of droplets from each nozzle 11. As the coating head 10, a droplet jet head that ejects a chemical solution by a droplet jet method (for example, an inkjet head that uses a stacked piezo drop-on-demand method) can be used. The method is not limited to this.

  The coating head 10 having such a configuration discharges the chemical liquid as droplets in accordance with the control from the overall control unit 40, and forms a predetermined coating pattern on the base material sheet transported by the transport mechanism.

  In addition, the chemical | medical solution discharged from the application head 10 is a liquid containing a chemical | medical agent. The specific kind of the drug is not particularly limited, but a drug that can be absorbed by the human body through the skin, that is, a drug that can be absorbed through the skin is preferable. Examples of such drugs include analgesic / anti-inflammatory agents such as indomethacin, ketoprofen, flurbiprofen, ibuprofen, viloxicam, methyl salicylate, glycol salicylate, l-menthol, dl-camphor, valinyl acid nonylate, capsaicin and the like. In addition, coronary vasodilators such as nitroglycerin, nifedipine, isosorbide nitrate, or asthma drugs such as procaterol and tulobuterol may be used as drugs. In addition to the above, general anesthetics, hypnotics / sedatives, antiepileptics, antipruritics, psychiatric drugs, skeletal muscle relaxants, autonomic drugs, antispasmodics, antiparkinson drugs, Histamine, cardiotonic, arrhythmic, diuretic, antihypertensive, vasoconstrictor, peripheral vasodilator, arteriosclerosis, cardiovascular, respiratory stimulant, antitussive expectorant, hormone, purulent disease External medicine, analgesic / antipruritic / astringent / anti-inflammatory drug, parasitic skin disease drug, hemostatic drug, gout treatment drug, diabetes drug, anti-malignant tumor drug, antibiotic, chemotherapeutic drug, narcotic, antidepressant Medicines, smoking cessation aids (nicotine), etc. can be used.

  Such a drug is dissolved in a solvent to form a drug solution. As the solvent, water or alcohol can be used depending on the properties of the drug. A chemical solution of a predetermined concentration in which a drug is dissolved in a solvent is prepared in a preparation tank, and the chemical solution is supplied from the preparation tank and stored in the chemical tank. The chemical solution stored in the chemical solution tank is fed to each nozzle 11 via the supply pipe by capillary action generated in the nozzle 11 when the coating head 10 ejects the chemical solution. In addition, the chemical | medical solution may further contain the binder and / or additive which improve the adhesiveness to a base material sheet. In addition, a chemical solvent may be added to the chemical solution in order to adjust the viscosity and surface tension of the chemical solution. In addition, a moisturizing agent may be added to the chemical liquid in order to prevent the chemical liquid from drying.

  The imaging unit 70 includes a light source 71 such as an LED, an EL, a lamp, and the like, and an imaging unit 72 disposed at a position where the emitted light from the light source 71 can be received. The imaging means 72 has an imaging element (for example, a CCD (Charge Coupled Device) sensor, a CMOS (Complementary Metal-Oxide Semiconductor) sensor, etc.) that converts received light into an electrical signal, and receives light emitted from the light source 71. Thus, an image signal is generated.

  As shown in FIG. 1, the light source 71 and the imaging unit 72 are held by the support mechanism 80 at positions facing each other. Thereby, the imaging means 72 can receive the light emitted from the light source 71.

  As shown in FIG. 2, the imaging unit 70 having such a configuration has an optical path of a light beam LH emitted from the light source 71 and incident on the imaging means 72, and droplets discharged from the coating head 10. It is arranged at a position where the flight trajectory FC overlaps.

  In the state of being arranged at the position, the imaging unit 72 captures a droplet that is flying on the optical path of the light beam LH and acquires a droplet image. In the droplet image captured in this way, the shadow of the droplet is projected.

  In addition, the imaging of a droplet image is performed by synchronizing the discharge of the droplet of the coating head 10, the light emission of the light source 71, and the exposure of an image pick-up element several times. By performing such multiple exposure, a clear droplet image is obtained. In addition, when a high-speed camera (high-speed camera) is employed as the imaging unit 72, a droplet image can be acquired without performing such multiple exposures.

  The support mechanism 80 functions as a moving unit that supports the imaging unit 70 and can change the position of the imaging unit 70.

  Specifically, as shown in FIG. 1, the support mechanism 80 is capable of moving a support (here, the imaging unit 70) in the arrangement direction (X-axis direction) of the nozzles 11. (First movement mechanism) 81 and a Y-axis movement mechanism (second movement mechanism) 83 capable of moving the support in the substrate sheet conveyance direction TD (Y-axis direction) perpendicular to the X-axis. doing. The support mechanism 80 further includes a rotational movement mechanism (third movement mechanism) 82 between the X-axis movement mechanism 81 and the Y-axis movement mechanism 83. The rotational movement mechanism (third movement mechanism) 82 is a mechanism that rotates the Y-axis movement mechanism 83 in a coordinate plane including the X-axis and the Y-axis.

  According to such a support mechanism 80, as shown in FIG. 3, the angle θ of the imaging means 72 with respect to the transport direction TD is changed from −90 ° to 90 ° in a coordinate plane including the X axis and the Y axis. It becomes possible.

  The above is the main component of the droplet discharge device 1A. In addition, the droplet discharge device 1A includes various mechanisms whose description is omitted in addition to the above configuration. For example, the droplet discharge device 1A further includes an encoder that outputs a pulse signal every time the transport band 92 is transported by a transport mechanism for a predetermined distance. As the encoder, for example, a rotary encoder that rotates according to the conveyance amount of the conveyance band 92 and outputs a pulse signal for each predetermined rotation amount can be employed. The pulse signal output from the encoder is used for specifying the discharge timing of the droplets from the nozzles or specifying the shooting timing by the imaging means 72.

[1-2. Functional configuration]
Next, the functional configuration of the droplet discharge device 1A will be described. FIG. 4 is a functional block diagram of the droplet discharge device 1A.

  As shown in FIG. 4, the overall control unit 40 of the droplet discharge apparatus 1A is configured as a microcomputer, and mainly includes a CPU 41, a ROM 42, a RAM 43, and the like. The overall control unit 40 implements various functions by reading a program stored in the ROM 42 and executing the program by the CPU 41.

  Specifically, the overall control unit 40 functionally realizes the application operation control unit 45, the imaging control unit 46, and the discharge state detection unit 47 by executing the above-described program.

  The application operation control unit 45 adjusts the voltage applied to the nozzles in the application head 10 on the basis of application data that defines a desired application pattern, thereby controlling the ejection of droplets from each nozzle, thereby applying the application operation. Is executed.

  The imaging control unit 46 controls the imaging operation by the imaging unit 70 and causes the imaging unit 72 to acquire a droplet image. The acquired image data of the droplet image is temporarily stored in the image memory 54 that can be accessed at high speed.

  The ejection state detection unit 47 has a function of detecting the ejection state of droplets related to each nozzle based on the droplet image. Specifically, the ejection state detection unit 47 obtains the size of the droplet area by counting the number of pixels included in the droplet area in the droplet image. Then, the discharge state detection unit 47 specifies the actual size (area) of the droplet based on the size of the droplet region and the photographing magnification.

  Here, if a reference calibration curve showing the relationship between the applied voltage (driving voltage) to the nozzle 11 and the size of the droplet obtained before the application operation is performed, the current ejection should be performed from the current driving voltage. The ideal droplet size can be determined.

  The discharge state detection unit 47 can detect the discharge state of each nozzle 11 by comparing the ideal droplet size thus obtained with the actual droplet size. It is possible to identify an abnormal nozzle that has not ejected a droplet and an abnormal nozzle that has a small discharge amount.

  In addition to specifying an abnormal nozzle, the discharge state detection unit 47 estimates the droplet amount of the currently discharged droplet based on the actual droplet size specified using the droplet image. You can also

  In order to estimate the current droplet amount, in addition to the reference calibration curve (first reference calibration curve) indicating the relationship between the drive voltage and the droplet size, the drive voltage obtained before the actual application operation is performed A second reference calibration curve indicating the relationship with the droplet amount is used. Since the first reference calibration curve and the second reference calibration curve have the drive voltage as a common parameter, the droplet size and liquid are determined based on the first reference calibration curve and the second reference calibration curve. A third reference calibration curve showing the relationship with the drop volume can be obtained.

  The discharge state detection unit 47 estimates the current droplet amount based on the actual droplet size by referring to the third standard calibration curve thus obtained.

  Further, the overall control unit 40 controls the display operation on the display device 51 configured by a liquid crystal display or the like. By the display operation, various information such as processing results and messages are displayed on the display device 51.

  In addition, the overall control unit 40 receives input of commands, parameters, and the like via the input device 52 such as a keyboard and a mouse. An operator (user) of the device can perform an input operation from the input device 52 while confirming the content displayed on the display device 51. The display device 51 and the input device 52 may be integrated as a touch panel.

  Still further, the overall control unit 40 can acquire a processing program, an operation parameter, or the like by controlling the reading device 53 that reads recorded contents from a recording medium RM such as a DVD or a CD.

[1-3. Discharge state detection operation]
Next, the operation of the droplet discharge device 1A will be described. FIG. 5 is a flowchart showing the operation of the droplet discharge apparatus 1A.

  As shown in FIG. 5, in step SP <b> 11, basic information used to detect the droplet discharge state is acquired.

  As basic information, there is a first reference calibration curve indicating the relationship between the driving voltage of the nozzle 11 and the size of the droplet. The first reference calibration curve is created by capturing a droplet image while changing the drive voltage in a state where the imaging unit 70 is disposed at the initial position NQ1 (see FIG. 3).

  When the imaging unit 70 is arranged at the initial position NQ1, the imaging means 72 is arranged at a position substantially perpendicular to the arrangement direction of the nozzles 11. Therefore, when the size of the droplet discharged from each nozzle 11 is obtained based on the droplet image, it is possible to reduce the necessity of performing a correction process considering the shooting magnification and the shooting distance. Calibration curves can be created and calibrated efficiently. Note that the first reference calibration curve may be created based on a droplet image obtained by photographing the droplets ejected from several representative nozzles or one nozzle.

  When estimating the current droplet amount, a second reference calibration curve indicating the relationship between the drive voltage and the droplet amount is also acquired as basic information.

  In the next step SP12, the imaging unit 70 is located at a position where it does not interfere with the conveyance of the base sheet, and is obliquely arranged with respect to the arrangement direction of the nozzles 11. Specifically, as shown in FIG. 3, the position of the imaging unit 70 is changed from the initial position NQ1 to the position NQ2. The position NQ2 is on the side of the transport band 92 and is an oblique position with respect to the arrangement direction of the nozzles 11. Such a change in the position of the imaging unit 70 makes it possible to change the position of the imaging means 72 in the arrangement direction of the nozzles 11 and the conveyance direction TD perpendicular to the arrangement direction, and in the same plane, the imaging means in the conveyance direction TD. The support mechanism 80 can change the angle θ of 72 from −90 ° to 90 °. Note that the position NQ2 of the imaging unit 70 when acquiring the droplet image is also referred to as a “detection position”.

  In step SP13, the coating head 10 is operated in response to a command from the coating operation control unit 45, and the application of the chemical solution to the base sheet is started.

  In step SP14, the imaging unit 72 operates in response to a command from the imaging control unit 46, and a droplet image is acquired.

  In the next step SP15, the ejection state detection unit 47 detects the ejection state of the droplet based on the droplet image.

  As described above, the droplet discharge device 1A acquires the droplet image in a state where the imaging unit 70 is disposed on the side of the transport band 92 and oblique to the arrangement direction of the nozzles 11, A droplet discharge state is detected based on the droplet image.

  If the imaging unit 70 is arranged on the side of the conveyance band 92, the imaging unit 70 can be prevented from obstructing the conveyance of the base sheet, so that the discharge state can be detected in real time during the application operation. It becomes possible to do. Further, since the droplet discharge device 1A detects the discharge state based on the droplet image related to the discharged droplet, the current discharge state can be grasped without time lag compared to the case where the pattern after application is confirmed. It becomes possible to do.

  Note that the position where the imaging unit 70 is arranged, that is, the position oblique to the arrangement direction of the nozzles 11, the optical path of the light beam incident on the imaging means 72 is oblique to the arrangement direction of the nozzles 11. It can also be expressed as a position.

  Further, when the optical path of the light beam incident on the imaging means 72 is inclined with respect to the arrangement direction of the nozzles 11, the position of the imaging unit 70 is a position where the shadow of each flying droplet does not overlap in the light beam. Become. In this manner, by arranging the imaging unit 70 at a position where the shadow of each flying droplet does not overlap in the light beam, an image relating to each droplet ejected from each nozzle 11 can be acquired. It becomes possible to accurately detect the discharge state of the liquid droplets discharged from each nozzle.

<2. Second Embodiment>
Next, a second embodiment of the present invention will be described. In the droplet discharge device 1B according to the second embodiment, droplet images are acquired simultaneously from two directions. The droplet discharge device 1B according to the second embodiment has substantially the same configuration and function as the droplet discharge device 1A except that the droplet images are simultaneously acquired from two directions using the two imaging units 70. The common parts are denoted by the same reference numerals and the description thereof is omitted. FIG. 6 shows a top view and a front view of a droplet discharge device 1B according to the second embodiment.

  As shown in FIG. 6, the droplet discharge device 1B according to the second embodiment has two sets of imaging units 70A and 70B. Then, each of the imaging units 70A and 70B is disposed at an oblique position with respect to the transport direction of the base sheet and on both sides of the transport band 92 for transporting the base sheet. To get.

  Then, the droplet discharge device 1B specifies the actual droplet size by averaging the droplet areas obtained from each of the two acquired droplet images.

  In this way, by acquiring droplet images from two directions and specifying the size of the droplets discharged from the nozzles 11 using the two acquired droplet images, the discharge of each nozzle 11 It becomes possible to detect the state more accurately.

  Specifically, the liquid droplets ejected from each nozzle 11 usually fly to the axis object with respect to the axis of the nozzle 11 and become substantially spherical at a location about 800 μm away from the surface of the nozzle 11. However, when the liquid droplet ejected from the nozzle 11 has a vertically long shape having a tail (tail) and is inclined with respect to the axis of the nozzle 11, the liquid is discharged depending on the arrangement position of the imaging means 72. The shape of the droplet in the droplet image changes greatly.

  Therefore, as in the present embodiment, by acquiring droplet images from two directions and specifying the size of the droplets discharged from the nozzle 11 using the two acquired droplet images. The size of the droplet can be specified with high accuracy regardless of the shape of the droplet, and the ejection state of each nozzle 11 can be detected more accurately.

<3. Modification>
Although the embodiments of the present invention have been described above, the present invention is not limited to the contents described above.

  For example, in each of the above embodiments, the light source 71 and the imaging unit 72 are illustrated as being held by the support mechanism 80 at positions facing each other. However, the light source 71 and the imaging unit 72 are separated from the light source 71. As long as the emitted light can be received, the light does not necessarily have to be disposed at the opposed positions.

  In each of the above embodiments, the first reference calibration curve is created based on the droplet image photographed at the initial position NQ1, but the present invention is not limited to this. The first reference calibration curve is based on the droplet image photographed at the detection position NQ2. A one-standard calibration curve may be created.

  Moreover, in the said 2nd Embodiment, although the case where the droplet discharge apparatus 1B had two sets of imaging units was illustrated, it is not limited to this, The aspect which has three or more sets of imaging units may be sufficient. Even in the case of having three or more sets of imaging units, each imaging unit is arranged on the side of the transport band 92 and at an oblique position with respect to the arrangement direction of the nozzles 11.

DESCRIPTION OF SYMBOLS 1A, 1B Droplet discharge apparatus 10 Application | coating head 11 Nozzle 40 Overall control part 45 Application | coating operation control part 46 Imaging | photography control part 47 Ejection state detection part 70, 70A, 70B Imaging unit 71 Light source 72 Imaging means 80 Support mechanism (support means)
81 X-axis moving mechanism (first moving mechanism)
82 Rotary movement mechanism (third movement mechanism)
83 Y-axis moving mechanism (second moving mechanism)
92 Transport band FC Flight trajectory LH Luminous flux NQ1 Initial position NQ2 Detection position TD Transport direction

Claims (6)

An ejection means having a plurality of ejection openings for ejecting liquid droplets on a substrate sheet on a conveyance zone conveyed in a certain direction;
A light source;
Imaging means for receiving light emitted from the light source and acquiring an image;
Detecting means for detecting a discharge state of the droplet using an image obtained by imaging the flying droplet ejected in the light beam incident on the imaging means by the imaging means;
With
The image pickup means is a droplet discharge device disposed at a position where a shadow of each droplet in flight does not overlap other droplets in the light beam and on the side of the transport zone. The plurality of discharge ports are arranged in a certain direction in the discharge means,
The liquid droplet ejection apparatus according to claim 1, wherein the imaging unit is disposed at an oblique position with respect to an arrangement direction of the plurality of ejection ports. And further comprising support means for supporting the light source and the imaging means in a state of facing each other,
The support means is
A first moving mechanism capable of moving the imaging means in a direction perpendicular to the transport direction;
A second moving mechanism capable of moving the imaging means in the same direction as the transport direction;
A rotational movement mechanism capable of rotationally moving at least one of the first movement mechanism and the second movement mechanism in the same plane;
The droplet discharge device according to claim 1, comprising:   The said imaging means is arrange | positioned in the position perpendicular | vertical with respect to the arrangement direction of these discharge ports, when acquiring the information used for the detection of the said discharge state before execution of application | coating operation | movement. Droplet discharge device. An ejection means having a plurality of ejection openings for ejecting liquid droplets on a substrate sheet on a conveyance zone conveyed in a certain direction;
Having two sets of imaging units each having a light source and an imaging unit that receives the light emitted from the light source and obtains an image;
Detecting means for detecting the discharge state of the droplet using each image obtained by imaging each flying droplet ejected in each light beam incident on each imaging means by each imaging means;
With
The two sets of the imaging units are respectively arranged at positions on both sides of the transport belt so that the shadow of each flying droplet does not overlap other droplets in the light beam incident on the imaging means. Droplet ejection device. A method for detecting a discharge state of droplets discharged from a plurality of discharge ports provided in a droplet discharge means,
a) An imaging unit that receives light emitted from a light source to acquire an image is located at a position where a shadow of each droplet in flight does not overlap another droplet in the light beam, The process of arranging
b) a step of discharging liquid droplets from a plurality of discharge ports to a base sheet on a transport band transported in a fixed direction;
c) detecting an ejection state of the droplet using an image obtained by imaging the flying droplet discharged into the light beam incident on the imaging unit by the imaging unit;
A method for detecting a discharge state of a droplet.

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