JP2010069430A - Method and device for coating liquid droplet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve detection accuracy of a landing position of a droplet on a substrate.
In the droplet application direction, the imaging field of view of the imaging device 30 is positioned in a first imaging range F1 including three or more droplets on the substrate, and the imaging device 30 captures an image in the first imaging range F1. The next imaging range of the imaging device 30 is determined by the first detection step of detecting the landing position of the droplets by performing image processing on the image of the droplets and the relative movement of the substrate and the imaging device 30. The second including three or more droplets on the substrate, which is composed of at least two droplets included in the first imaging range F1 and new droplets not included in the first imaging range F1. And a second detection step of detecting the landing positions of the droplets by performing image processing on the image of the droplets captured by the imaging device 30 in the second imaging range F2 by the image processing device. Having .
[Selection] Figure 3

Description

  The present invention relates to a droplet coating method and apparatus.

  2. Description of the Related Art Conventionally, as a technique for manufacturing a color filter substrate or the like using an ink jet coating method, there is a technique in which droplets ejected from nozzles provided on a coating head are applied by landing on a specific number of positions on the substrate.

  In the droplet application method described in Patent Document 1, the imaging range of the imaging device is sequentially positioned in the adjacent imaging range on the substrate by relative movement of the substrate and the imaging device, and the droplets included in each imaging range are positioned. Each individual is imaged by the imaging device, and the relative positional relationship between the reference position (positioning mark) on the substrate and the imaging position of each droplet (in other words, the landing position of the droplet on the substrate) is the relative movement amount between the substrate and the imaging device. And the landing position of each droplet is detected.

If the detected landing position of a droplet is shifted from the target landing position on the substrate, the droplet on the substrate is adjusted by adjusting the dropping timing of the nozzle corresponding to the droplet on the coating head. It is intended to improve the position accuracy of the landing position.
JP 2005-14216

  In the droplet application method described in Patent Document 1, the landing position of each droplet on the substrate is calculated based on the relative movement amount between the substrate and the imaging device, and the operation accuracy of the relative movement device between the substrate and the imaging device is increased. It will be included.

  An object of the present invention is to improve the detection accuracy of the landing position of a droplet on a substrate.

  According to a first aspect of the present invention, there is provided a droplet coating method in which droplets ejected from nozzles provided on a coating head are landed and applied to a plurality of positions on a substrate. A first imaging position that is positioned in a first imaging range that includes droplets and detects the landing position of the droplets by performing image processing on an image of the droplets captured by the imaging device in the first imaging range by the image processing device. Due to the detection process and relative movement of the substrate and the imaging device, the next imaging range of the imaging device was not included in the first imaging range with at least two droplets included in the first imaging range. A second imaging range including three or more droplets on a substrate made of new droplets is used, and an image of a droplet imaged by the imaging device in the second imaging range is processed by an image processing device. Due to the landing of those droplets It is obtained as a second detection step of detecting the location.

  According to a second aspect of the invention, in the first aspect of the invention, when the second imaging range is picked up by the imaging device, the imaging device is focused on at least two droplets included in the first imaging range. As described above, the substrate and the imaging device are relatively moved in the facing direction.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the substrate is further moved relative to the coating head in one direction at a predetermined speed, and a plurality of nozzles juxtaposed in a direction intersecting the direction of the relative movement. When the droplets ejected at a predetermined droplet timing from the first droplet are landed on the substrate, the droplet timing is determined based on the landing positions of the droplets detected in the first detection step and the second detection step. Is adjusted.

  According to a fourth aspect of the present invention, there is provided a droplet applying apparatus that applies droplets ejected from nozzles provided on an application head at a plurality of positions on the substrate, and applies the application head and the substrate along the substrate surface. A first relative movement device that moves relative to the image pickup device, an image pickup device that picks up an image of a droplet ejected from the nozzle and landed on the substrate, and image processing of an image of the liquid droplet picked up by the image pickup device An image processing device that detects a landing position of the droplet, the coating head, the first relative movement device, an imaging device, and a control device that controls driving of the image processing device. The imaging field of view of the imaging device is positioned in the first imaging range including three or more droplets on the substrate, and the image of the droplet imaged by the imaging device in the first imaging range is subjected to image processing by the image processing device. By them While detecting the landing position of the droplet and relative movement of the substrate and the imaging device, the next imaging range of the imaging device is changed to at least two droplets included in the first imaging range and the first imaging range. A second imaging range including three or more droplets on a substrate made of new droplets that were not included is set as a second imaging range, and an image of the droplets captured by the imaging device in the second imaging range is displayed as an image processing device. The landing positions of these droplets are detected by image processing according to the above.

  The invention of claim 5 further comprises a second relative movement device for relatively moving the substrate and the imaging device in the opposing direction in the invention of claim 4, wherein the control device is an imaging device. The second relative movement device is controlled so that the imaging device is focused on at least two droplets included in the first imaging range during imaging of the second imaging range by It is.

  According to a sixth aspect of the invention, in the fourth or fifth aspect of the invention, the control device moves the substrate relative to the coating head in one direction at a predetermined speed, and is juxtaposed in a direction intersecting the direction of the relative movement. When the droplets ejected from the plurality of nozzles at a predetermined droplet timing are landed on the substrate, the droplet timing is determined based on the landing position of each droplet detected by image processing by the image processing device. It is intended to be adjusted.

  According to a seventh aspect of the present invention, there is provided a droplet coating method in which droplets ejected from nozzles provided in a coating head are landed and applied to a plurality of positions on a substrate, and an imaging field of view of an imaging device is set to a plurality of droplets on the substrate Detecting a landing position of each droplet included in the first imaging range from an image captured by the imaging device in the first imaging range, and the substrate. Due to the relative movement with the imaging device, the imaging field of view of the imaging device is made up of a plurality of droplets that are included in the first imaging range and new droplets that are not included in the first imaging range. A second detection that is positioned in a second imaging range including a droplet and detects the landing position of each droplet included in the second imaging range from an image captured by the imaging device in the second imaging range. And a process.

(Claims 1 and 4)
(a) In the second detection step, due to relative movement between the substrate and the imaging device, the next imaging range of the imaging device is changed to at least two droplets included in the first imaging range and the first imaging range. A second imaging range including three or more droplets on the substrate made of new droplets that were not included in the second imaging range, and an electronic image of the droplets captured by the imaging device in the second imaging range The landing positions of these droplets are detected by image processing by the processing device. Thereby, the imaging position of each droplet within the second imaging range on the substrate is at least two mediation points each consisting of at least two droplets shared by both the first and second imaging ranges. By interposing, the position can be detected with respect to the reference position defined in the first imaging range on the substrate. Therefore, the relative positional relationship between the reference position determined in the first imaging range on the substrate and the imaging position of each droplet in the second imaging range (in other words, the landing position of each droplet on the substrate) is The electronic image of the droplet imaged by the imaging device in the imaging range 2 is detected by image processing by the image processing device. The landing position of each droplet is detected by image processing of an electronic image of the droplet in the second imaging range with reference to the reference position defined in the first imaging range. Since it is not calculated based on the relative movement amount, it does not include the operation accuracy of the relative movement device of the substrate and the imaging device, and the detection accuracy can be improved.

  (b) The droplet landing position detection operation in the second imaging range in (a) above is repeated in the remaining range on the substrate, whereby each droplet is dropped in the entire range where the droplet on the substrate has been dropped. It is possible to detect the landing position of the liquid droplets with high accuracy, and to inspect the positional deviation of the droplets with respect to the target landing position.

(Claims 2 and 5)
(c) When the height position of the second imaging range on the substrate relative to the imaging device deviates from the height position of the first imaging range on the substrate relative to the imaging device, from the focus of the imaging device. The second imaging range is out of range, and the position detection accuracy of the droplets in the second imaging range is impaired. Accordingly, when the imaging device captures the second imaging range, the substrate is positioned in the height direction (focusing point) with respect to the imaging device so that the imaging device is focused on at least two droplets included in the first imaging range. By relative movement in the depth direction), it is possible to improve the position accuracy of the image pickup position of the liquid droplet in the second image pickup range, and consequently improve the detection accuracy of the liquid drop landing position.

(Claims 3 and 6)
(d) The substrate is moved relative to the coating head in one direction at a predetermined speed, and droplets discharged at a predetermined dropping timing from a plurality of nozzles juxtaposed in a direction crossing the relative movement direction are placed on the substrate. When the position of the droplet landing position in the direction along the direction of relative movement is detected according to the above-described (a) and (b), when the droplet is landed, the nozzle corresponding to the droplet of the coating head is dropped. By adjusting the timing, the positional deviation of the landing position of the droplet with respect to the substrate can be corrected, and the positional accuracy of the landing position of the droplet with respect to the substrate can be improved.

  FIG. 1 is a schematic diagram showing a droplet applying device, FIG. 2 is a schematic diagram showing an imaging device that images a droplet landed on a substrate, and FIG. 3 shows a first imaging range and a second imaging range on the substrate. FIG. 4 is a schematic diagram showing a droplet in the first imaging range and a droplet in the second imaging range, and FIG. 5 is a schematic diagram showing an operation for focusing the imaging device on the droplet on the substrate. It is.

  As shown in FIG. 1, the droplet coating apparatus 10 has a product substrate K, which is an object to be coated, in a horizontal state (a state along the X-axis direction and the Y-axis direction orthogonal to the X-axis direction in FIG. 1). The substrate moving table 11 to be placed, the Y axis moving device 12 that holds the substrate moving table 11 and moves it in the Y axis direction, and the substrate moving table 11 in the X axis direction via the Y axis moving device 12 An X-axis moving device 13 to be moved, a plurality of coating heads 20 that discharge a coating liquid such as ink as droplets E toward the substrate K on the substrate moving table 11, and imaging for imaging the droplets E on the substrate K An apparatus 30; an image processing apparatus 40 that performs an inspection based on an image of a droplet E imaged by the imaging apparatus 30; a display unit 41 that displays an image of the droplet E imaged by the imaging apparatus 30; Y-axis movement device 12, X-axis movement Location 13, the coating head 20, and a controller 50 for controlling the drive such as an imaging apparatus 30 and the image processing apparatus 40.

  The substrate moving table 11 is stacked on the Y-axis moving device 12 and is provided so as to be movable in the Y-axis direction. The substrate moving table 11 is moved in the Y-axis direction by the Y-axis moving device 12. The substrate K is placed on the substrate moving table 11 by its own weight. However, the present invention is not limited to this. For example, a mechanism such as an electrostatic chuck or an adsorption chuck is provided to hold the substrate K. May be. At the end portion of the substrate moving table 11, a discharge stabilizing portion 11 </ b> A for stabilizing the discharge of each coating head 20 is provided. The discharge stabilizing portion 11A includes a dummy discharge tray for each coating head 20, a wipe blade for wiping the discharge surface of each coating head 20, and the like.

  The Y-axis moving device 12 is a mechanism that guides and moves the substrate moving table 11 in the Y-axis direction. The Y-axis moving device 12 is electrically connected to the control device 50, and its driving is controlled by the control device 50. As the Y-axis moving device 12, for example, a linear motor moving mechanism using a linear motor as a driving source, a feed screw moving mechanism using a motor as a driving source, or the like is used.

  The X-axis moving device 13 is a mechanism that moves the Y-axis moving device 12 while guiding it in the X-axis direction. The X-axis moving device 13 is electrically connected to the control device 50, and its driving is controlled by the control device 50. As the X-axis moving device 13, for example, a linear motor moving mechanism using a linear motor as a driving source, a feed screw moving mechanism using a motor as a driving source, or the like is used.

  The coating head 20 ejects the coating liquid supplied from a liquid tank (not shown) containing a coating liquid such as ink as droplets E from the plurality of nozzles 21, and these droplets E on the substrate K. This is an ink jet head that is applied by landing at multiple positions. The coating head 20 includes a plurality of piezoelectric elements (not shown) corresponding to the plurality of nozzles 21 that discharge the droplets E, respectively. The nozzles 21 are formed on the discharge surface in a straight line at a predetermined pitch (interval). For example, the number of nozzles 21 is about several tens to several hundreds, the diameter of the nozzles 21 is about several μm to several tens of μm, and the pitch of the nozzles 21 is about several tens μm to several hundreds of μm. .

  The coating head 20 is electrically connected to the control device 50, and its driving is controlled by the control device 50. The coating head 20 ejects droplets (ink droplets) E from each nozzle 21 in response to application of a driving voltage to each piezoelectric element. Here, the coating liquid has volatility. This coating solution is composed of a solute that remains as a residue on the substrate K and a solvent that dissolves (disperses) the solute. For example, the ink that is the coating liquid is composed of various components such as a pigment, a solvent (ink solvent), a dispersant, and an additive.

  Here, the droplet applying apparatus 10 of the present embodiment targets the color filter substrate K of the liquid crystal display panel as an application target. The product substrate K, which is an actual product, is provided with convex portions on the surface of the substrate K that form a lattice pattern as a black matrix BM. Then, coloring droplets (R: red, G: green, B: blue ink) discharged from the nozzle 21 of the coating head 20 of the droplet coating apparatus 10 are partitioned by the convex portions, respectively. A predetermined amount is applied to concave portions at a large number of positions constituting a certain application range. The droplets applied to the recesses are dried to form a colored layer in the recesses.

  When applying droplets ejected from the nozzles 21 of the coating heads 20 of the droplet coating apparatus 10 to the concave portions at many positions of the substrate K, the coating head 20 is tilted with respect to the X-axis direction by a rotation mechanism, The pitch in the X-axis direction of the nozzles 21 adjacent to each other in the coating head 20 is matched to the pitch in the X-axis direction of the concave portions to be colored with the same color among the concave portions of the substrate K placed on the substrate moving table 11. Then, the Y-axis moving device 12 of the substrate moving table 11 is driven by the control device 50, and the substrate K on the substrate moving table 11 is moved relative to the coating head 20 below the coating head 20 in the Y direction. The liquid droplets discharged from each of the nozzles 21 of the head 20 are sequentially applied to the concave portions to be colored with the same color of the substrate K at a predetermined dropping timing t (dropping time interval). For example, when red R ink is ejected from each nozzle 21 of the application head 20, the ink is applied to each of the concave portions that color red. Note that the application pitch p in the Y-axis direction with respect to the substrate K can be adjusted by changing the ejection frequency (dropping timing t) of the droplet E from each nozzle 21 of the application head 20.

  However, the droplet applying device 10 detects the landing position of the droplet discharged from the nozzle 21 of the applying head 20 on the substrate K with high accuracy using the imaging device 30, the image processing device 40, and the inspection substrate KA. Therefore, the following configuration is provided.

  Note that the imaging device 30 images the droplet E ejected from each nozzle 21 of the coating head 20 and landed on the inspection substrate KA. At this time, in order to detect the position of the substrate K on the substrate moving table 11, the imaging device 30 also images the positioning marks M1 and M2 (FIG. 3) attached to the inspection substrate KA. The imaging device 30 is electrically connected to the image processing device 40 and the control device 50, and the driving thereof is controlled by the control device 50, and the captured image of each droplet E is transmitted to the image processing device 40. For example, a CCD (Charge Coupled Device) camera or the like is used as the imaging device 30.

  The image processing device 40 detects the landing position of each droplet E by performing image processing on the electronic image of each droplet E and the positioning marks M1 and M2 transmitted from the imaging device 30. As the image processing apparatus 40, for example, a computer or the like is used.

  The display unit 41 connected to the image processing device 40 displays electronic images of the respective droplets E and the positioning marks M1 and M2 transmitted from the imaging device 30 to the image processing device 40. As the display unit 41, a liquid crystal display, a CRT display, or the like is used.

  The control device 50 includes a microcomputer that centrally controls each unit, and a storage unit that stores application information related to application, various programs, and the like (none of which are shown). The application information includes a predetermined application pattern such as a dot pattern, an inclination angle of the application head 20, information on an ejection frequency of the application head 20, and a moving speed of the substrate K. As the application information, application information for manufacturing application and application information for inspection application (including a pattern for inspection and a pattern for forming a solvent atmosphere) are stored in the storage unit.

  The control device 50 of the droplet applying apparatus 10 operates as follows in order to improve the detection accuracy of the landing position of the droplet E on the inspection substrate KA.

(A) Discharging Step The inspection substrate KA is placed on the substrate moving table 11, and the Y-axis moving device 12 of the substrate moving table 11 is driven by the control device 50 in the same manner as the droplet applying operation to the product substrate K. The inspection substrate KA on the substrate moving table 11 is moved relative to the coating head 20 below the coating head 20 in the Y direction at a predetermined speed, and the relative movement direction of the coating head 20 with respect to the inspection substrate KA is the above. Each droplet E ejected at a dropping timing t from a plurality of nozzles 21 juxtaposed at a constant pitch in the X direction orthogonal to the Y direction corresponds to each recess of the product substrate K on the inspection substrate KA. Land on each application area defined by the position.

(B) Detection process (Figure 2)
The inspection substrate KA is positioned directly below the imaging device 30, and the first detection process and the second detection process are performed as follows.

(B-1) First detection step (FIGS. 3 and 4)
(1) The imaging field of view of the imaging device 30 is a rectangle having a size including three or more droplets E on the inspection substrate KA, that is, 12 in this embodiment (3 in the X direction and 4 in the Y direction). First, the field of view is counted from the droplets located in the lower right among the droplets applied in a matrix in the X direction and the Y direction on the inspection substrate KA (see FIG. 3), The relative position in the horizontal direction between the inspection substrate KA and the imaging device 30 is set so as to be positioned in the first imaging range F1 including four droplets on the left side in the X direction and three droplets on the upper side in the Y direction. The moving device 13 is controlled and adjusted.

  (2) In the first imaging range F1, an electronic image of the droplet E captured by the imaging device 30 is subjected to image processing by the image processing device 40, thereby detecting the landing position of the droplet E.

  At this time, one droplet E1 defined in the first imaging range F1 on the inspection substrate KA is set as a reference droplet, the position of the reference droplet E1 is set as a reference position (x0, y0), and this reference position ( The landing position of another droplet Ei is detected based on the relative positional relationship with x0, y0). In the present embodiment, the droplet E located at the lower right of the first imaging range F1 is used as the reference droplet E1.

  The relative positional relationship between the reference droplet E1 and the other droplet Ei in the first imaging range F1, in other words, the landing position of the other droplet Ei, the reference droplet E1 and the other droplet Ei in the first imaging range F1. The image of the droplet Ei is detected by image processing by the image processing device 40. That is, the image processing apparatus 40 obtains the number of pixels mi between the image of the reference droplet E1 and the image of the other droplets Ei, and the pixel size mi (the pixel size in the vertical direction or the horizontal size) By multiplying the pixel size in the direction), the distance from the reference droplet E1 to another droplet Ei, in other words, the (positioning mark M1) with respect to the reference position (x0, y0) of the reference droplet E1 on the inspection substrate KA. , Which is also for M2), the landing position (xi, yi) of another droplet Ei is obtained. Thereby, the landing positions of all the droplets Ei in the first imaging range F1 can be obtained.

(B-2) Second detection step (FIGS. 3 and 4)
(1) The substrate moving table 11 is moved by the Y-axis moving device 12 and the X-axis moving device 13, the inspection substrate KA is moved relative to the imaging device 30 in the XY direction, and the image field of the imaging device 30 is changed to the next imaging range. Is positioned in the second image range F2. The second image range F2 includes at least two droplets included in the first imaging range F1, in this embodiment, two droplets E2a arranged in the Y direction at the upper left of the first image range F1. , E2b and three or more liquid droplets E2a, E2b on the right side of the two droplets E2a, E2b on the inspection substrate KA composed of new droplets Ej that were not included in the first imaging range F1. This is a visual field range including 12 droplets E (three in the X direction and four in the Y direction), four on the left side in the X direction and three on the upper side in the Y direction, counted from the droplet E2a. In other words, the first imaging range F1 and the second imaging range F2 share at least two mediation points, in this embodiment, two mediation droplets E2a and E2b and partially overlap each other.

  (2) In the second imaging range F2, the image processing device 40 performs image processing on the electronic image of the droplet E imaged by the imaging device 30, thereby detecting the landing position of the droplet E.

  The imaging position of each droplet E in the second imaging range F2 on the inspection substrate KA is via two intermediate droplets E2a and E2b shared by both the first and second imaging ranges F1 and F2. Thus, the position can be detected with respect to the reference position of the reference droplet E1 set in the first imaging range F1.

  Accordingly, the relative positional relationship between the reference droplet E1 in the first imaging range F1 and each droplet Ej in the second imaging range F2, in other words, the landing position of each droplet Ej is determined as the second imaging range F2. The image of the intermediary droplet E2a (or E2b) and the other droplet Ej can be detected by image processing by the image processing device 40. That is, since the landing positions of the intermediate droplets E2a and E2b with respect to the reference droplet E1 on the inspection substrate KA have already been obtained according to the above (B-1), the intermediate droplet E2a (or E2b) is obtained in the image processing apparatus 40. ) And the image of another droplet Ej are obtained, and the pixel number mj is multiplied by the pixel size of the imaging device 30 to obtain the reference droplet E1 from the intermediate droplet E2a (or E2b). Distance to other droplets Ej (in other words, from the intermediary droplet E2a (or E2b) on the inspection substrate KA (for the reference droplet E1 or the positioning marks M1, M2), etc. The landing position (xj, yj) of the droplet Ej is obtained. The landing positions of all droplets Ej can be obtained.

  (B-3) The operation of detecting the landing position of the droplet E in the second imaging range F2 in (B-2) is repeated in the remaining range on the inspection substrate KA. Thereby, the landing position of each droplet E can be detected in the entire range on the inspection substrate KA.

  (B-4) When the substrate moving table 11 is moved by the Y-axis moving device 12 and the X-axis moving device 13 during the imaging by the imaging device 30 in the second imaging range F2 of (B-2) described above, the substrate moving table 11, the height position of the inspection substrate KA on the table 11 with respect to the imaging device 30 may deviate from A to B as shown in FIG. In this case, since the captured image of the second imaging range F2 by the imaging device 30 becomes blurred, the contour position of the droplet E cannot be accurately determined, and the position of the droplet E is relied on the contour position. The position detection accuracy to detect will fall. In such a case, the inspection substrate KA and the imaging device 30 are relatively positioned in the height direction so that the imaging device 30 is focused on the two mediating droplets E2a and E2b included in the first imaging range F1. Move. In FIG. 5, the height position of the inspection substrate KA with respect to the imaging device 30 is changed from B to C. The relative movement of the inspection substrate KA and the imaging device 30 in the height direction is performed, for example, by providing a Z-direction moving device of the imaging device 30 and adjusting the height position of the imaging device 30 by this driving. Note that the imaging device 30 and the inspection substrate KA need only be able to move relative to each other in the Z direction, so a Z direction moving device may be provided on the table 11 side.

  Further, whether or not the medium droplets E2a and E2b are out of focus of the imaging device 30 is determined by, for example, the size of the medium droplets E2a and E2b from the image of the medium droplets E2a and E2b captured in the first imaging range Fl. (Diameter or area) is calculated and stored individually, and each of the intermediate droplets E2a calculated from the stored data and the images of the intermediate droplets E2a and E2b imaged in the second imaging range F2, The size of E2b is compared, and the determination is made based on whether or not the difference exceeds the allowable value. That is, when the droplet E deviates from the focus of the imaging device 30, the outline is blurred as described above. Therefore, when image processing is performed, the outer shape is detected smaller than when the image is in focus. Therefore, the size of the droplet E out of focus is smaller than the image of the droplet E in focus.

  In order to make each droplet E within the depth of focus of the imaging device 30 in the first imaging range F1, the following may be performed.

  In a multi-tone captured image, when the object to be imaged (droplet E) is within the depth of focus, the contour of the image becomes clear and becomes more blurred as the deviation from the depth of focus increases. Since the gradation change becomes steeper as the contour becomes sharper, the gradation change rate at the contour portion of the image of the droplet E is obtained, and the comparison is made by comparing whether the change rate is equal to or greater than an allowable value. It is possible to determine whether or not the droplet E within the imaging range F1 is at the depth of focus of the imaging device 30. The second imaging range F2 and thereafter may be focused similarly.

(C) Control process When the landing positions of the droplets E are detected in the entire range on the inspection substrate KA as described above in (B), it is possible to inspect whether or not the landing positions of the droplets E with respect to the target position are misaligned.

  Then, the Y direction that is the relative movement direction of the inspection substrate KA relative to the application head 20 when the droplet E discharged from each nozzle 21 of the application head 20 is landed on the inspection substrate KA in the above-described (A). When the position of the landing position of the droplet E is displaced in the direction along the direction, the position deviation is corrected by adjusting the above-described (A) dropping timing t of the nozzle 21 corresponding to the droplet E.

  On the other hand, when there is a positional deviation in the landing position of the droplet E in the X direction, which is a direction orthogonal to the relative movement direction of the inspection substrate KA with respect to the coating head 20, it is determined whether or not the positional deviation exceeds an allowable value. When the allowable value is exceeded, an alarm for notifying the operator that the application cannot be executed is displayed on a display device such as a monitor. That is, since the nozzles 21 are formed on the coating head 20 at a predetermined pitch, the positions of the nozzles 21 cannot be individually adjusted. For this reason, when there is a displacement in the landing position of the droplet E in the X direction, it may be considered that there is a problem such as a bend in the discharge direction of the droplet from one of the nozzles 21 due to some cause. This is because maintenance is required to solve this problem.

According to the present embodiment, the following operational effects can be obtained.
(a) In the second detection step, due to the relative movement of the substrate and the imaging device 30, the next imaging range of the imaging device 30 is changed to at least two intermediate droplets E2a included in the first imaging range F1, E2b and the second imaging range F2 including three or more droplets on the substrate made of new droplets that were not included in the first imaging range F1, and the imaging device 30 in the second imaging range F2 The image processing apparatus 40 performs image processing on the electronic image of the liquid droplet imaged by the above, thereby detecting the landing position of the liquid droplet. Thereby, the imaging positions of the respective droplets in the second imaging range F2 on the substrate are the at least two intermediate droplets E2a and E2b shared by both the first and second imaging ranges F1 and F2, respectively. It is possible to detect the position with respect to the reference position (x0, y0) of the reference droplet E1 defined in the first imaging range F1 on the substrate by way of at least two mediation points. Accordingly, the relative positional relationship between the reference position (x0, y0) of the reference droplet E1 defined in the first imaging range F1 on the substrate and the imaging position of each droplet in the second imaging range F2 (in other words, The landing position of each droplet on the substrate) is detected by performing image processing on the electronic image of the droplet captured by the imaging device 30 in the second imaging range F2 by the image processing device 40. The landing position of each droplet is based on the image processing of the electronic image of the droplet in the second imaging range F2 with reference to the reference position (x0, y0) of the reference droplet E1 defined in the first imaging range F1. Since it is detected and is not calculated based on the relative movement amount of the substrate and the imaging device 30, the operation accuracy of the relative movement devices 12 and 13 of the substrate and the imaging device 30 is not included, and the detection accuracy is improved. it can.

  In addition, since at least two intermediate droplets E2a and E2b are used, the direction can be determined from the positional relationship between the two intermediate droplets E2a and E2b. For this reason, even if a rotational deviation occurs between the imaging device 30 and the inspection substrate KA when the imaging range is switched, the second deviation is not affected by the rotational deviation. The landing position of each droplet Ej within the imaging range F2 can be detected with reference to the reference position (x0, y0).

  (b) By repeating the detection operation of the droplet landing position in the second imaging range F2 in (a) above in the remaining range on the substrate, the landing position of each droplet in the entire range on the substrate is increased. It is possible to detect with high accuracy, and to inspect the positional deviation of these droplets with respect to the target landing position.

  (c) When the substrate is moved relative to the imaging device 30, the height position of the second imaging range F2 on the substrate relative to the imaging device 30 is the first imaging range F1 on the substrate is the imaging device 30. When the position is shifted with respect to the height position, the second imaging range F2 is shifted from the focal point of the imaging device 30, and the position accuracy of the imaging position of the liquid droplet in the second imaging range F2 is impaired. Therefore, the second imaging range F2 by the imaging device 30 is also adjusted so that the imaging device 30 is focused on at least two mediating droplets E2a and E2b included in the first imaging range F1 during imaging. By relative movement in the height direction (depth depth direction) with respect to the imaging device 30, the positional accuracy of the imaging position of the droplet in the second imaging range F2 is improved, and as a result, the detection accuracy of the landing position of the droplet is improved. It can be improved.

  (d) The substrate is moved relative to the coating head 20 at a set speed in one direction, and discharged from the plurality of nozzles 21 juxtaposed in a direction intersecting the relative movement direction with the substrate in the coating head 20 at the dropping timing t. When the liquid droplets landed on the substrate, the positional deviation of the liquid droplet landing position in the direction along the relative movement direction with respect to the coating head 20 on the substrate was detected by the above-described (a) and (b). In this case, by adjusting the dropping timing t of the nozzle 21 corresponding to the droplet of the coating head 20, the positional deviation of the landing position of the droplet with respect to the substrate is corrected, and the positional accuracy of the landing position of the droplet with respect to the substrate is improved. It can be improved.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like without departing from the gist of the present invention. It is included in the present invention. For example, the droplet landing position detection operation according to the present invention is not limited to the droplet landed on the inspection substrate, but can be performed on the droplet landed on the product substrate.

  Moreover, although the example in which the second imaging range F2 is set to the upper left with respect to the first imaging range F1 has been described, the present invention is not limited to this, and it may be set in any of horizontal, vertical, and diagonal directions. good. In short, it is only necessary to set so that at least two droplets among the droplets located in the current imaging range are included in the next imaging range.

  In addition, the example has been described in which two adjacent droplets E (mediating droplets E2a and E2b) included in the first imaging range F1 are duplicated and captured in the second imaging range F2. The droplets E may be taken in duplicate or not adjacent to each other. As the distance between the two mediating droplets E2a and E2b is larger, the detection accuracy of the rotational deviation can be improved. In addition, as long as the relative rotational deviation generated between the substrate KA and the imaging device 30 is negligible as a result of the relative movement of the substrate KA and the imaging device 30 in the horizontal direction (XY direction), the droplets to be taken in redundantly E may be one.

FIG. 1 is a schematic view showing a droplet applying apparatus. FIG. 2 is a schematic diagram illustrating an imaging apparatus that images a droplet landed on a substrate. FIG. 3 is a schematic diagram showing a first imaging range and a second imaging range on the substrate. FIG. 4 is a schematic diagram showing droplets in the first imaging range and droplets in the second imaging range. FIG. 5 is a schematic diagram showing the operation of focusing the imaging device on the droplet on the substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Droplet coating device 11 Substrate moving table 12 Y-axis moving device 13 X-axis moving device 20 Coating head 21 Nozzle 30 Imaging device 40 Image processing device 50 Control device K, KA Substrate F1 First imaging range F2 Second imaging range

Claims (7)

In a droplet application method in which droplets ejected from nozzles provided in a coating head are landed and applied at multiple positions on a substrate,
An imaging field of view of the imaging device is positioned in a first imaging range including three or more droplets on the substrate, and an image of the droplet imaged by the imaging device in the first imaging range is subjected to image processing by the image processing device. A first detection step of detecting the landing positions of the droplets by:
Due to the relative movement of the substrate and the imaging device, at least two droplets included in the first imaging range and new droplets that were not included in the first imaging range in the next imaging range of the imaging device. A second imaging range including three or more droplets on the substrate, and the droplets imaged by the imaging device in the second imaging range are image-processed by the image processing device. And a second detection step of detecting the landing position of the liquid droplets.   When the imaging device captures the second imaging range, the substrate and the imaging device are relatively moved in the facing direction so that the imaging device is focused on at least two droplets included in the first imaging range. The droplet coating method according to claim 1. The substrate is moved relative to the coating head in one direction at a predetermined speed, and droplets discharged from a plurality of nozzles juxtaposed in a direction crossing the relative movement direction are landed on the substrate at a predetermined dropping timing. When letting
The droplet application method according to claim 1 or 2, wherein the dropping timing is adjusted based on the landing positions of the droplets detected in the first detection step and the second detection step. In a droplet application device that applies and applies droplets ejected from nozzles provided on an application head to a large number of positions on a substrate,
A first relative movement device that relatively moves the coating head and the substrate in a direction along the substrate surface;
An imaging device for imaging a droplet discharged from the nozzle and landed on a substrate;
An image processing device for detecting a landing position of the droplet by performing image processing on an image of the droplet imaged by the imaging device;
The coating head, the first relative movement device, the imaging device, and a control device for controlling the drive of the image processing device;
The control device
An imaging field of view of the imaging device is positioned in a first imaging range including three or more droplets on the substrate, and an image of the droplet imaged by the imaging device in the first imaging range is subjected to image processing by the image processing device. To detect the landing position of these droplets,
Due to the relative movement of the substrate and the imaging device, at least two droplets included in the first imaging range and new droplets that were not included in the first imaging range in the next imaging range of the imaging device. A second imaging range including three or more droplets on the substrate, and the droplets imaged by the imaging device in the second imaging range are image-processed by the image processing device. A droplet applying apparatus for detecting a landing position of a liquid. A second relative movement device for relatively moving the substrate and the imaging device in their opposing directions;
The second relative movement device is configured so that the control device focuses the imaging device on at least two droplets included in the first imaging range when imaging the second imaging range by the imaging device. The droplet coating apparatus according to claim 4, wherein the apparatus is controlled. The control device moves the substrate relative to the coating head in one direction at a predetermined speed, and drops droplets discharged at a predetermined dropping timing from a plurality of nozzles juxtaposed in a direction intersecting the relative movement direction. When landing on the board,
6. The droplet applying device according to claim 4, wherein the droplet timing is adjusted based on a landing position of each droplet detected by performing image processing with the image processing device. In a droplet application method in which droplets ejected from nozzles provided in a coating head are landed and applied at multiple positions on a substrate,
The imaging field of view of the imaging device is positioned in a first imaging range including a plurality of droplets on the substrate, and each liquid included in the first imaging range from an image captured by the imaging device in the first imaging range. Detecting the landing position of the droplet;
Due to the relative movement between the substrate and the imaging device, the imaging field of view of the imaging device is changed from the droplets included in the first imaging range and the new droplets not included in the first imaging range. A second imaging range including a plurality of droplets, and a landing position of each droplet included in the second imaging range is detected from an image captured by the imaging device in the second imaging range. 2. A droplet coating method comprising: two detection steps.

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