JP2010015052A - Droplet application device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correctly apply a droplet discharged from a nozzle of a coating head to a concave portion partitioned by a convex portion even if distortion is generated in a lattice of the convex portion of a substrate to be coated.
In a droplet coating method in which a droplet discharged from a nozzle 21 of a coating head 20 is applied to a concave portion 2 defined by a convex portion 1 having a lattice shape on the surface of a substrate K, the surface of the substrate K is projected. The step of imaging the portion 1 and the recess 2 and the droplets discharged from the nozzles 21 of the coating head 20 on the surface of the substrate K while relatively moving the substrate K and the coating head 20 in one direction along the surface of the substrate K. While applying to the recess 2, the relative position in the direction orthogonal to the one direction along the surfaces of the substrate K of the application head 20 and the substrate K is corrected based on the captured images of the protrusion 1 and the recess 2. Comprising a process.
[Selection] Figure 1

Description

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

  In the color filter substrate of the liquid crystal display panel, as described in Japanese Patent Application Laid-Open No. H10-228707, convex portions forming a lattice pattern as a black matrix BM are provided on the surface of the substrate. Then, a predetermined amount of colored droplets (ink) (R: red, G: green, B: blue) discharged from the nozzles of the coating head is applied to the concave portions defined by the convex portions. The droplets applied to the recesses are dried to form a colored layer in the recesses.

Here, the coating head has a plurality of nozzles arranged in a straight line. When applying droplets discharged from the nozzles of the coating head to the concave portions of the substrate, the coating head is tilted with respect to the X-axis direction (one of the two directions XY orthogonal to each other) to The pitch of the adjacent nozzles in the X-axis direction is matched with the X-axis direction pitch of the concave portions of the substrate placed on the substrate moving table (the pitch of the concave portions to be colored in the X-axis direction). Then, while relatively moving the substrate and the coating head in the Y-axis direction, droplets discharged from each of the plurality of nozzles of the coating head are applied to each of the concave portions to be colored with the same color on the surface of the substrate. .
Japanese Patent Laid-Open No. 9-230129

  In a large color filter substrate of several meters square, distortion is generated in the grid pattern of convex portions provided on the surface of the substrate. This distortion of the lattice pattern is caused by insufficient accuracy of the photomask in the substrate manufacturing process, insufficient accuracy of the optical lens, or the like.

  When the substrate to be coated of the droplet coating apparatus is distorted in the above-described lattice pattern (black matrix BM), the protrusions extended along the Y-axis direction of the substrate placed on the substrate moving table The portions are distorted so as to be displaced in the X-axis direction, and the concave portions between the adjacent convex portions in the X-axis direction are also displaced in the X-axis direction. In such a substrate, when the droplets discharged from each of the plurality of nozzles of the coating head are applied to each of the concave portions of the substrate while relatively moving the substrate and the coating head in the Y-axis direction, the substrate and the coating head With the relative movement in the Y-axis direction, the convex part extending in the Y-axis direction is displaced in the X-axis direction with respect to the coating head, so that the liquid droplets dropped from the nozzle of the coating head from the concave part of the substrate It comes off and adheres to the upper surface of the convex portion, and a predetermined colored layer cannot be formed in the concave portion of the substrate, causing a color mixture or the like to be defective.

  An object of the present invention is to apply a liquid droplet to a concave portion of a substrate while relatively moving the substrate and the coating head in the − direction, so that the position of the convex portion extending in the − direction is accompanied by the relative movement. Even if the position is shifted in the direction perpendicular to the negative direction, the liquid droplets ejected from the nozzles of the coating head are to be correctly applied to the concave portions defined by the convex portions.

  The invention according to claim 1 is a droplet coating apparatus that applies droplets ejected from a nozzle of a coating head to concave portions defined by lattice-shaped convex portions provided on the surface of the substrate. An imaging device that images the portion and the recess, a first moving device that relatively moves the substrate and the coating head in one direction along the surface of the substrate, and the coating head and the substrate along the surface of the substrate, A second moving device that relatively moves in a direction orthogonal to the one direction; and a droplet that is ejected from a nozzle of the coating head while the substrate and the coating head are relatively moved in the one direction by the first moving device. Is applied to the concave portion of the surface of the substrate, the second moving device is controlled based on the images of the convex portion and the concave portion imaged by the imaging device, and the coating head and the substrate in the direction orthogonal to the one direction are relative to each other. The correct position It is obtained by the so and a control device.

  According to a second aspect of the present invention, in the first aspect of the present invention, the control device is orthogonal to the one direction from a preset position of the picked-up image of the convex portion arranged along the one direction. The second moving device is controlled based on the deviation in the direction.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the imaging device is provided integrally with the coating head.

  According to a fourth aspect of the present invention, there is provided a droplet coating method in which droplets ejected from a nozzle of a coating head are applied to concave portions defined by lattice-shaped convex portions provided on a substrate surface. A convex portion while applying a droplet discharged from the nozzle of the coating head to the concave portion of the surface of the substrate while relatively moving the substrate and the coating head in one direction along the surface of the substrate. And a step of correcting the relative position in the direction orthogonal to the one direction along the surface of the substrate of the coating head and the substrate based on the captured image of the recess.

  According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the captured image of the convex portion arranged along the one direction is shifted from a preset position in a direction perpendicular to the one direction. Based on this, the relative positions of the coating head and the substrate in the direction orthogonal to the one direction along the surface of the substrate are corrected.

(Claims 1 and 4)
(a) While relatively moving the substrate and the coating head in one direction along the surface of the substrate, while applying the droplets discharged from the nozzles of the coating head to the recesses on the surface of the substrate, Based on this, the relative positions of the coating head and the substrate in the direction orthogonal to the one direction along the surface of the substrate are corrected. That is, when it is recognized that the convex portion along the one direction is displaced in the direction orthogonal to the one direction with respect to the coating head based on the captured images of the convex portion and the concave portion, By correcting the relative position in the direction orthogonal to the one direction by the amount of the positional deviation, the droplet dropping position from the nozzle of the coating head can be matched with the concave portion of the substrate.

(Claims 2 and 5)
(b) When the convex portion along the one direction is displaced in the direction perpendicular to the one direction with respect to the coating head, the direction from the preset position of the convex portion to the direction perpendicular to the one direction Based on the deviation, the position deviation can be detected correctly. This corrects the relative position of the substrate and the coating head in the direction perpendicular to the one direction by the amount of the positional deviation, so that the droplet dropping position from the nozzle of the coating head is correctly aligned with the concave portion of the substrate. Can do.

(Claim 3)
(c) By providing the imaging device integrally with the coating head, the image center of the imaging device and the nozzle center of the coating head can be easily and fixedly aligned, and the image center of the imaging device is the center of the recess of the substrate. Therefore, the position where the droplet is dropped from the nozzle can be matched with the center of the concave portion of the substrate with high accuracy.

  FIG. 1 is a schematic diagram showing a droplet applying device, FIG. 2 is a schematic diagram showing a substrate, FIG. 3 is a schematic diagram showing an image of a substrate in which the center of a concave portion of the substrate is aligned with the image center of an imaging device, and FIG. 5 is a waveform diagram showing waveform data obtained by processing an image of the imaging device by the image processing device, FIG. 5 is a diagram showing the relationship between the image shift amount of the imaging device and the sum of squared differences, and FIG. 6 is based on the imaging result of the imaging device. It is a schematic diagram which shows feedback control delay operation of a coating head.

  As shown in FIG. 1, the droplet applying apparatus 10 has a substrate moving table on which a substrate K, which is an object to be applied, is placed in a horizontal state (in FIG. 1, along the X-axis direction and the Y-axis direction perpendicular thereto). 11, a Y-axis moving unit 12 that holds the substrate moving table 11 and moves it in the Y-axis direction, and an X-axis moving unit 13 that moves the substrate moving table 11 in the X-axis direction via the Y-axis moving unit 12. And a table driving device 14 for driving the moving units 12 and 13. Further, the droplet applying device 10 includes a plurality of coating heads 20 that discharge a coating liquid such as ink as droplets toward the substrate K on the substrate moving table 11, and an imaging device 30 that images the droplets on the substrate K. And an image processing device 40 that processes an image of a droplet imaged by the imaging device 30, and a control device 50 that controls the table driving device 14, each coating head 20, the imaging device 30, the image processing device 40, and the like. It has. In the droplet applying apparatus 10, a head position control module 15 is installed above the substrate moving table 11, and a coating head 20, an imaging apparatus 30, and a head moving apparatus 60 described later are provided in the module 15.

  The substrate moving table 11 is stacked on the Y-axis moving unit 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 unit 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.

  The Y-axis moving unit 12 is a mechanism that guides and moves the substrate moving table 11 in the Y-axis direction. The X-axis moving unit 13 is a mechanism that guides and moves the Y-axis moving unit 12 in the X-axis direction. These moving units 12 and 13 are driven by a table driving device 14, and the table driving device 14 is controlled by a control device 50. As the moving units 12 and 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 application head 20 is installed above the substrate moving table 11 and ejects application liquid supplied from a liquid tank (not shown) containing application liquid such as ink as droplets from a plurality of nozzles 21. It is. The coating head 20 incorporates a plurality of piezoelectric elements (not shown) corresponding to the plurality of nozzles 21 for discharging droplets. 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.

  Furthermore, the coating head 20 is supported by a rotation mechanism (not shown) so as to be rotatable in the θ direction (rotation direction along the XY plane in FIG. 1). The coating head 20 is tilted by a predetermined tilt angle with respect to the relative movement direction of the relatively moving substrate K by the rotation mechanism, and coating is performed in this state. When coating is performed on the substrate K that moves relatively in the Y-axis direction, by changing the tilt angle of the coating head 20, the X of droplets discharged from the adjacent nozzles 21 of the coating head 20 is changed. The coating pitch in the axial direction can be adjusted. In addition, the application pitch in the Y-axis direction can be adjusted by changing the droplet discharge frequency (discharge timing).

  The imaging device 30 is an imaging camera that images each droplet landed on the substrate K, and functions as a detection unit that detects each droplet. 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 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 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.

  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. As shown in FIGS. 1 and 2, the substrate K is provided with convex portions 1 that form a lattice-like pattern as a black matrix BM on the surface of the substrate K. A single substrate K is provided with a plurality of liquid crystal display panel (three in the example of FIG. 1) black matrixes BM, that is, convex portions 1 in a lattice pattern. Then, coloring droplets (R: red, G: green, or B: blue ink) discharged from a nozzle 21 of a coating head 20 (to be described later) of the droplet coating apparatus 10 are partitioned by the convex portion 1. A predetermined amount is applied to the recess 2 to be formed. The droplets applied to the recess 2 are dried to form a colored layer in the recess 2. The convex part 1 of the lattice pattern of the substrate K in FIG. 2 is provided with concave portions 2 of 15 columns horizontally and 6 rows vertically, but the actual lattice BM of the substrate K is 1000 columns horizontally or more and 1000 rows vertically. The above recess 2 is provided.

  When the droplets discharged from the nozzles 21 of the coating heads 20 provided in the droplet coating apparatus 10 are applied to the concave portions 2 of the substrate K, the coating head 20 is tilted with respect to the X-axis direction by the rotation mechanism described above. The pitch in the X-axis direction of the nozzles 21 adjacent to each other in the coating head 20 is the pitch in the X-axis direction of the recesses 2 to be colored in the same color among the recesses 2 of the substrate K placed on the substrate moving table 11 (FIG. 2). In the example shown in the example, every second). Then, the Y-axis moving unit 12 of the substrate moving table 11 is driven by the table driving device 14, 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. A droplet discharged from each nozzle 21 of the coating head 20 is applied to each of the recesses 2 on the substrate K where the same color is to be colored. 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 recesses 2 that color red.

  However, even if the droplet coating apparatus 10 distorts the lattice pattern of the convex portion 1 of the substrate K, the droplet discharged from the nozzle 21 of the coating head 20 is applied to the concave portion 2 partitioned by the convex portion 1. In order to make it possible to drop and apply correctly, the following configuration is provided.

  The droplet applying device 10 has a plurality of coating heads 20 installed in a head unit 20A, and the head unit 20A is driven by a head moving device 60 by a head moving unit 61 in the X-axis direction and the Z-axis direction (the Z-axis direction is In the X-axis direction and the Y-axis direction). The head moving device 60 is controlled by the control device 50. The head moving unit 61 includes a linear motor moving mechanism using a linear motor as a drive source.

  In the droplet coating device 10, the Y-axis drive unit 12 driven by the table driving device 14 constitutes the first moving device of the present invention, and the substrate K and the coating head 20 are placed on the surface of the substrate K. It moves relatively in one direction (Y-axis direction) along. The head moving unit 61 of the head moving device 60 constitutes a second moving device of the present invention, and the coating head 20 and the substrate K are placed along the surface of the substrate K in the X-axis direction orthogonal to the one direction. Move relative.

  Further, the droplet applying device 10 fixedly attaches the imaging device 30 to the head unit 20 </ b> A, and the imaging device 30 is provided integrally with each coating head 20. Thereby, the imaging device 30 and the coating head 20 are adjusted to an appropriate positional relationship (for example, the image center of the imaging device 30 and the center of any nozzle 21 of the coating head 20 are fixedly aligned in the X-axis direction). Thus, the relative positional relationship between the coating head 20 and the substrate K can be grasped through the position of the positioning mark M attached to the substrate K on the substrate moving table 11 imaged by the imaging device 30. As described above, when the substrate K on the substrate moving table 11 moves below the coating head 20 in the Y-axis direction and passes through the imaging device 30, the imaging device 30 moves more than the coating head 20 with respect to the moving substrate K. The distance L is provided at a position preceding the Y-axis direction (FIG. 6). Therefore, the convex part 1 of the grid pattern on the substrate K and the concave part 2 partitioned by the convex part 1 reach below the imaging device 30 (imaging area) earlier than the coating head 20, and the image is captured. An imaging signal is taken into the image processing device 40. The timing at which the image processing device 40 starts to capture the imaging signal of the imaging device 30 may be from the time when the movement of the substrate moving table 11 is started to apply the coating liquid onto the substrate K, or the positioning mark M on the substrate K. Based on the relative positional relationship between the coating head 20 and the substrate K and the movement position of the substrate movement table 11 which are grasped with reference to the above, the top of the convex portion 1 of the lattice pattern (the convex portion 1 at the upper end in FIG. It is also possible to obtain the point in time when reaching downward and from this time.

  As described above, the control device 50 moves the substrate K and the coating head 20 from the nozzles 21 of the coating head 20 while moving the substrate K and the coating head 20 in the Y-axis direction by the Y-axis moving unit 12 (first moving device) of the substrate moving table 11. While the ejected droplets are applied to the concave portion 2 on the surface of the substrate K, the convex portion 1 of the substrate K is distorted, so that the convex portion 1 along the Y-axis direction extends in the X-axis direction with respect to the coating head 20. Even if the positional deviation occurs, the following control operation is performed in order to make the droplet dropping position from the nozzle 21 of the coating head 20 coincide with the concave portion 2 of the substrate K.

  (A) The preset reference image of the convex portion 1 arranged along the Y-axis direction of the substrate K is picked up by the image pickup device 30, and the reference waveform data corresponding to the reference image is obtained by the image processing device 40.

  The reference image includes one recess 2 in the X-axis direction (width direction) in the imaging area of the imaging device 30 and a part of each of the recesses 2 on both sides thereof, in other words, two that extend in the Y-axis direction. The convex part 1 is assumed to enter. The reference image is an image when the relative positional relationship between the coating head 20 and the imaging device 30 and the substrate K is an ideal positional relationship, and the center of the imaging region of the imaging device 30 is the recess 2 as shown in FIG. To the center (the center of the two convex portions 1). The relative positional relationship between the coating head 20, the imaging device 30, and the substrate K is adjusted so that this image is obtained.

  The imaging signal of the reference image of the imaging device 30 is taken into the image processing device 40. The image processing device 40 is an image pickup signal of the image pickup device 30 (a charge signal generated from each light receiving element arranged in a matrix. In this embodiment, the light receiving elements are arranged in 20 columns horizontally and 15 rows vertically. Charge signals generated from 20 light receiving elements in a predetermined row, for example, the 8th row, are taken in. A graph of the charge signal captured by the image processing apparatus 40 is a waveform shown in FIG. This waveform data is obtained from the reference image of the substrate K imaged by the imaging device 30, and becomes the reference waveform data.

  (B) While the substrate K and the coating head 20 are moved relative to each other in the Y-axis direction by the Y-axis moving unit 12 of the substrate moving table 11, the droplets ejected from the nozzles 21 of the coating head 20 are actually When applying from the upper end of FIG. 2 to the concave portion 2 on the surface, the convex portion 1 along the Y-axis direction is imaged by the imaging device 30 at every predetermined time interval or every predetermined movement distance. A signal (charge signal from each light receiving element) is captured by the image processing device 40. The graph of the charge signal taken in by the image processing device 40 is the actual waveform data shown in FIG. If the actual waveform data matches the reference waveform data (matches within an allowable range), the relative positional relationship in the X-axis direction between the coating head 20 and the convex portion 1 along the Y direction of the substrate K is the above-mentioned ideal. There is no deviation from the relative relative positional relationship. On the other hand, when a positional deviation in the X-axis direction occurs between the coating head 20 and the convex portion 1 along the Y-axis direction of the substrate K, for example, the convex portion 1 along the Y-axis direction of the substrate K is leftward. When the positional deviation corresponding to one light receiving element of the image pickup device 30 occurs, the actual waveform data is as shown in FIG. In each part along the Y-axis direction of the substrate K, the image processing apparatus 40 determines the difference between the actual waveform data and the reference waveform data in the X-axis direction for each part along the Y-axis direction of the substrate K. The obtained imaging signal of the imaging device 30 is processed as in the following (1) to (3).

(1) Find the direction of displacement.
Difference calculation is performed to subtract the actual waveform data from the reference waveform data. The waveform data obtained as a result of the difference calculation is as shown in FIG.

  If the actual waveform data and the reference waveform data match, there is no difference between them, and the obtained waveform data is constant at 0 (zero). For example, if the substrate K is displaced in the left direction by one light receiving element, the waveform data as shown in FIG. 4C having peaks and valleys corresponding to the difference is obtained. Here, it is determined whether the captured image of the substrate K is shifted to the left or right along the X-axis direction according to the order in which the peaks and valleys of the waveform appear. As seen from the left side, when the waveform starts from a peak as shown in FIG. 4C, the captured image of the substrate K is shifted to the left side, whereas when the waveform starts from the valley, the captured image of the substrate K is on the right side. It is determined that there is a deviation.

２乗演算して得た波形データのａ〜ｂの範囲の和を求めるのは、基板Ｋの前述の基準画像の相隣る２本の凸部１以外の凸部１データを排除するためである。求めた差分２乗和を、予め求めてある基板Ｋの撮像画像における凸部１のずれ量と差分２乗和の関係を表わすテーブルに当てはめて、今回の基板Ｋの撮像画像における凸部１のずれ量を求める。 (2) Find the amount of deviation.
The waveform data obtained by the difference calculation of the above (1) is squared to obtain the waveform data of FIG. The sum (difference square sum Lv) is obtained from the obtained waveform data by the following equation.

The reason why the sum of the ranges of a to b of the waveform data obtained by the square calculation is obtained is to eliminate the convex portion 1 data other than the two adjacent convex portions 1 of the reference image of the substrate K. is there. The calculated difference square sum is applied to a table representing the relationship between the deviation amount of the convex portion 1 in the captured image of the substrate K and the difference square sum obtained in advance, and the convex portion 1 in the captured image of the current substrate K is calculated. Find the amount of deviation.

  The table representing the relationship between the shift amount of the captured image of the substrate K and the sum of squared differences is for one light receiving element (image processing device 40) in the right and left directions from the state where the reference waveform data is obtained. The waveform data of the image is acquired while shifting the imaging position of the imaging device 30 (relative position between the imaging device 30 and the substrate K) by one pixel on the monitor display screen), and the difference 2 described above is obtained for each waveform data. Create a sum of multipliers. The graph shown in FIG. 5 corresponds to the above-described table, and shows the relationship between the number of pixels on the horizontal axis and the difference square sum Lv on the vertical axis. The sum of squares Lv is the minimum value (ideally 0 (zero)) in a state where there is no deviation in the captured image of the substrate K, and the convex portion 1 in the captured image of the substrate K is shifted to the left by m pixels. The difference square sum Lv is Lvm at a position shifted by m pixels to the left from the origin 0 in FIG.

(3) Correction of deviation between coating head 20 and substrate K When the above deviations (1) and (2) are recognized between coating head 20 and convex portion 1 along the Y-axis direction of substrate K, the head The head unit 20A is driven by the moving device 60, and the coating head 20 is moved in the X-axis direction with respect to the substrate K in the shift direction (1) by the shift amount (2), and the shift is corrected. . The movement amount (deviation correction amount) f of the coating head 20 by the head moving device 60 is as follows when the deviation amount is m pixels. However, the pixel resolution of the imaging device 30 is assumed to be p (μm / pixel).
f = m · p
Thereby, the center of the nozzle 21 of the coating head 20 is matched with the center of the recess 2 of the substrate K on the substrate moving table 11.

In the droplet applying device 10, as described above, the imaging device 30 is provided at a position preceding the applying head 20 by a distance L with respect to the moving substrate K (FIG. 6). The nozzle 21 of the coating head 20 is moved with respect to the portion of the substrate K according to the above (3) from the timing when the imaging device 30 recognizes the deviation of the above (1) and (2) for a certain portion along the Y-axis direction of the substrate K. The following feedback delay time t is provided until the timing when the movement of the coating head 20 is completed so as to correct the deviation. However, the moving speed (coating scanning speed) of the substrate K along the Y-axis direction by the Y-axis moving unit 12 is V.
t = L / V

  As described above, the control device 50 moves the substrate K and the coating head 20 relative to each other in the Y-axis direction by the Y-axis moving unit 12 of the substrate moving table 11 and drops droplets discharged from the nozzles 21 of the coating head 20 on the substrate. While applying to the concave portion 2 on the surface of K, the above (B) (1) to (3) are repeated, and droplets are dropped from the nozzle 21 of the coating head 20 regardless of the distortion of the convex portion 1 of the substrate K. The position is matched with the recess 2 of the substrate K.

According to the present embodiment, the following operational effects can be obtained.
(a) While the substrate K and the coating head 20 are relatively moved in the Y-axis direction along the surface of the substrate K, while applying the droplets discharged from the nozzles 21 of the coating head 20 to the recesses 2 on the surface of the substrate K, Based on the captured images of the convex portion 1 and the concave portion 2, the relative positions in the X-axis direction perpendicular to the Y-axis direction along the surfaces of the coating head 20 and the substrate K of the substrate K are corrected. That is, based on the captured images of the convex portion 1 and the concave portion 2, the convex portion 1 along the Y-axis direction is displaced from the coating head 20 in the X-axis direction due to the distortion of the convex portion 1 along the Y-axis direction. It is recognized that the relative position of the substrate K and the coating head 20 in the X-axis direction orthogonal to the Y-axis direction is corrected by the positional deviation, thereby correcting the relative position of the substrate K and the coating head 20 from the nozzle 21 of the coating head 20. The droplet dropping position can be matched with the concave portion 2 of the substrate K.

  (b) When the substrate K is distorted in the convex portion 1 along the Y-axis direction, based on the deviation of the convex portion 1 from the preset position in the X-axis direction orthogonal to the Y-axis direction. Thus, it is possible to correctly detect a positional shift in the X-axis direction of the convex portion 1 with respect to the coating head 20 caused by the distortion. As a result, by correcting the relative position of the substrate K and the coating head 20 in the X-axis direction orthogonal to the Y-axis direction by the positional deviation, the droplet dropping position from the nozzle 21 of the coating head 20 can be determined. It is possible to correctly match the concave portion 2 of K.

  (c) By providing the imaging device 30 integrally with the coating head 20, the image center of the imaging device 30 and the center of the nozzle 21 of the coating head 20 can be easily and fixedly aligned. Is matched with the center of the concave portion 2 of the substrate K, so that the droplet dropping position from the nozzle 21 can be matched with the center of the concave portion 2 of the substrate K with high accuracy.

  (d) The image processing device 40 captures a predetermined one row of charge signals from the charge signals from the light receiving elements arranged in a matrix of the imaging device 30, and uses this one row of charge signals to generate Y The positional deviation in the X-axis direction with respect to the coating head 20 of the convex portion 1 along the axial direction is obtained. For this reason, since the number of processed data can be remarkably reduced as compared with the case where the above distortion is obtained using the charge signals of all the light receiving elements of the imaging device 30, the time required for calculating the above-mentioned positional deviation is shortened, and the distortion is reduced. The time required to correct the positional deviation of the convex portion 1 with respect to the coating head 20 can be shortened as much as possible. As a result, it becomes possible to cause the coating head 20 to follow the distortion of the convex portion 1 with high accuracy, so that the droplet dropping position from the nozzle 21 of the coating head 20 can be matched more accurately with the concave portion 2 of the substrate K. The quality of the manufactured color filter can be further 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.

  That is, in the above-described embodiment, the positional deviation in the X-axis direction with respect to the coating head 20 of the convex portion 1 along the Y-axis direction caused by the distortion in the X-axis direction of the convex portion 1 along the Y-axis direction of the substrate K is corrected. As described in the example, the positional deviation in the X-axis direction with respect to the coating head 20 of the convex portion 1 along the Y-axis direction due to an error in the straightness of the Y-axis moving unit 12 that moves the substrate moving table 11 in the Y-axis direction. That is, the present invention can also be applied to correction of the positional deviation of the convex portion 1 with respect to the coating head 20 due to a mechanical movement error. Also in this case, while the substrate K and the coating head 20 are relatively moved in the Y-axis direction by the Y-axis moving unit 12 of the substrate moving table 11, the liquid droplets discharged from the nozzles 21 of the coating head 20 are transferred to the concave portion 2 of the substrate K. Since the convex portion 1 along the Y-axis direction is displaced in the X-axis direction with respect to the coating head 20 when applied to the coating, it can be performed in the same manner as in the above-described embodiment. is there.

FIG. 1 is a schematic view showing a droplet applying apparatus. FIG. 2 is a schematic view showing a substrate. FIG. 3 is a schematic diagram illustrating an image of the substrate in which the center of the concave portion of the substrate is aligned with the image center of the imaging apparatus. FIG. 4 is a waveform diagram showing waveform data obtained by processing an image of the imaging device by the image processing device. FIG. 5 is a diagram showing the relationship between the image shift amount of the image pickup apparatus and the sum of squared differences. FIG. 6 is a schematic diagram showing the feedback control delay operation of the coating head based on the imaging result of the imaging apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Convex part 2 Concave part 10 Droplet coating device 12 Y-axis moving part (1st moving apparatus)
20 Coating head 21 Nozzle 30 Imaging device 50 Control device 61 Head moving part (second moving device)
K substrate

Claims (5)

In a droplet coating apparatus that applies droplets ejected from a nozzle of a coating head to concave portions defined by lattice-shaped convex portions provided on the surface of a substrate,
An imaging device for imaging the convex and concave portions of the surface of the substrate;
A first moving device that relatively moves the substrate and the coating head in one direction along the surface of the substrate;
A second moving device that relatively moves the coating head and the substrate along the surface of the substrate in a direction orthogonal to the one direction;
While the substrate and the coating head are relatively moved in the one direction by the first moving device, while the droplets ejected from the nozzles of the coating head are applied to the recesses on the surface of the substrate, the projections imaged by the imaging device A liquid comprising: a control device that controls the second moving device based on a captured image of the recess and corrects a relative position of the coating head and the substrate in a direction orthogonal to the one direction. Drop application device.   The control device controls the second moving device based on a deviation of a captured image of the convex portion arranged along the one direction from a preset position in a direction orthogonal to the one direction. The droplet applying apparatus according to claim 1.   The droplet coating apparatus according to claim 1, wherein the imaging device is provided integrally with a coating head. In a droplet application method for applying droplets ejected from a nozzle of an application head to concave portions defined by lattice-shaped convex portions provided on the surface of a substrate,
Imaging the convex and concave portions of the surface of the substrate;
While relatively moving the substrate and the coating head in one direction along the surface of the substrate, while applying the droplets discharged from the nozzles of the coating head to the recesses on the surface of the substrate, based on the captured images of the projections and the recesses, And a step of correcting a relative position in a direction perpendicular to the one direction along the surface of the substrate along the surface of the substrate.   Based on the deviation of the captured image of the convex portion arranged along the one direction from the preset position in the direction orthogonal to the one direction, along the surface of the substrate of the coating head and the substrate, The droplet coating method according to claim 4, wherein a relative position in a direction orthogonal to the one direction is corrected.

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