KR20170138051A - Inspection apparatus, inspection method, and functional liquid droplet ejection apparatus - Google Patents

Abstract

The present invention relates to an inspection device, an inspection method, and a functional liquid discharging device. The inspection device is to properly correct a discharge condition of a functional liquid based on an inspection result of a discharge state of the functional liquid by using a photographing result of the functional liquid. The inspection device (1) inspects the discharge state of the functional liquid from a nozzle. The inspection device (1) includes: a photographing unit (10) photographing multiple droplets (21) formed on an inspection sheet (20) by the functional liquid discharged from the nozzle; a measuring unit (11a) measuring a formation state of the droplet (21) based on the photographing result of the photographing unit (10); and a selection unit (11b) performing pattern matching of a whole image of the droplet having a predetermined form and the whole photographed image of the photographing unit (10) for each of the multiple droplets (21), wherein the selection unit (11b) selects the droplet which becomes an object to be measured in the measuring unit (11a) among the multiple droplets (21) based on a matching result.

Description

TECHNICAL FIELD [0001] The present invention relates to an inspection apparatus, an inspection method, and a functional liquid dispensing apparatus,

The present invention relates to an inspection apparatus, an inspection method, and a functional liquid ejection apparatus for inspecting a discharge state of a functional liquid from a nozzle.

2. Description of the Related Art Conventionally, an organic light emitting diode (OLED), which is a light emitting diode using light emission of an organic EL (electroluminescence), is known. An organic EL display using such an organic light emitting diode has recently been attracting attention as a next-generation flat panel display (FPD) because it is thin, lightweight, low in power consumption, excellent in terms of response speed, viewing angle and contrast ratio.

The organic light emitting diode has a structure in which an organic EL layer is interposed between an anode and a cathode on a substrate. The organic EL layer is formed by laminating, for example, a hole injecting layer, a hole transporting layer, a light emitting layer, an electron transporting layer, and an electron injecting layer in this order from the anode side. In forming these layers (particularly, the hole injection layer, the hole transport layer, and the light emitting layer) of these organic EL layers, a method of ejecting the functional liquid of the organic material onto the substrate by, for example, an inkjet method is used.

However, since each layer of the organic EL layer is formed of a thin film of several tens of nm each in the organic light emitting diode, if an ejection failure of, for example, a functional liquid occurs in any one of the layers, . Therefore, in order to suppress the discharge failure of the functional liquid, it is necessary to observe the state of the droplet formed by the functional liquid ejected on the substrate such as the inspection substrate or the inspection sheet, It is necessary to check the discharging state of the functional liquid and correct the discharging condition based on the inspection result. The object to be cleaned at the time of correction is, for example, a substrate for inspection or a sheet for inspection.

Patent Document 1 discloses an apparatus for inspecting the discharging state of a functional liquid on the basis of a state of a droplet formed by the above-described inkjet method. The apparatus includes an imaging means for imaging functional liquid droplets landed on a test substrate, An analyzing means for analyzing the diameter of the droplet using an image of the droplet, and a calculating means for calculating the volume of the functional droplet on the basis of the diameter of the functional droplet or the like. Patent Document 1 discloses that the driving waveform of the driving element of the nozzle, that is, the discharging condition is controlled based on the calculated volume of the functional liquid droplet.

However, a large number of droplets that do not become a proper shape (for example, a complete circle) due to the nature of the functional liquid (ink) or the contamination of the nozzles. If the droplet is not a proper shape, the ejection condition can not be corrected based on the inspection result. Even if corrected, good results can not be obtained after correction.

On the other hand, Patent Document 2 discloses a functional liquid ejection method for ejecting a function from a plurality of nozzles provided in a functional liquid ejection head to form droplets of a functional liquid on a substrate, An image forming step of obtaining an image of an enemy by comparing an outline shape of an image of each liquid obtained in the image pick-up step with an outline shape of a complete circle of a normal pattern, an image not reaching a threshold matching rate as an abnormal image, An image processing step of selecting, as a normal image, an image having reached the threshold value; and an image processing step of obtaining the landing area of the functional liquid based on the image selected as the normal image in the image processing step, By controlling the discharge amount of the functional liquid of the functional liquid, it is possible to appropriately correct the discharge amount of the functional liquid, that is, It is disclosed.

Japanese Laid-Open Patent Publication No. 2005-119139 Japanese Laid-Open Patent Publication No. 2010-188263

In the method described in Patent Document 2, as shown in Fig. 9A, if the nozzle state or the like is normal and the outer shape of the image (captured image) L1 of the liquid droplet to be imaged is a complete circle, the image L1 is a normal pattern . 9B, if the nozzle state or the like is not normal and the outer shape of the droplet captured image L1 is not a perfect circle, the image L1 is determined as an abnormal pattern, and as shown in Fig. 9C , The nozzle state and the like are normal but the outer shape of the droplet captured image L1 is not a perfect circle due to the presence of the foreign substance C1 in the droplet, the image L1 is judged as an abnormal pattern. However, in the method described in Patent Document 2, as shown in Fig. 9D, when the outer shape of the droplet captured image L1 is a complete circle, although the nozzle state is normal but the foreign object C1 is present in the droplet, . The liquid droplet is largely formed as much as the foreign object C1 is present. Therefore, if the ejection condition based on the captured image is corrected by including the captured image L1 of the droplet containing the foreign object C1 as a normal pattern, I can not.

The same applies to the case where a droplet is not formed on the foreign object C1 but on a portion where damage or the like exists on the object such as a sheet for inspection.

When a lyophilic test sheet is used as the object to be inspected, depending on the functional liquid, when all of the conditions such as the nozzle state are normal, as shown in Fig. 10A, the liquid droplet captured image L2 becomes a double concentric circle .

In the method described in Patent Document 2, the image L2 of Fig. 10A is determined to be a normal pattern because the outer shape is a complete circle, and as shown in Fig. 10B, The captured image L2 of the liquid droplet in which the contour is not a complete circle is largely deviated from the center of the large circle. However, in the method described in Patent Document 2, as shown in Fig. 10C, the cause image L2 of a perfect cause as a double circle which is not a concentric circle is determined as a normal pattern.

In the case where the captured image L2 of Fig. 10A is obtained and the captured image L2 of Fig. 10C is obtained, since the penetration form of the functional liquid differs in the lyophilic test sheet, in these cases, The amount of the functional liquid penetrated into the test sheet, that is, the discharge amount of the functional liquid differs. Therefore, when the captured image L2 shown in Fig. 10C is a normal pattern and the ejection condition based on the captured image is corrected, it can not be properly corrected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to make it possible to more appropriately correct discharge conditions of a functional liquid based on inspection results of discharging states of functional liquid using imaging results of functional liquid droplets.

The present invention for solving the above problems is an inspection apparatus for inspecting a discharge state of a functional liquid from a nozzle, comprising: an image pickup section for picking up a plurality of droplets formed on a target object by a functional liquid discharged from the nozzle; For each of the plurality of droplets, pattern matching between the entire captured image in the imaging unit and the entire droplet image having a predetermined shape, based on the imaging result of the liquid droplet And a selection unit that selects a liquid droplet to be measured by the metrology unit among the plurality of droplets based on the matching result.

And a reference image selection unit that selects an image of the liquid droplet having the predetermined shape from among the captured images of the plurality of droplets captured by the imaging unit.

It is preferable that the captured image and the liquid droplet image having the predetermined shape are gray scale images expressed by 256 tones.

It is preferable that the picked-up image and the liquid droplet image having the predetermined shape are color images in which each color is represented by 256 gradations.

According to another aspect of the present invention, there is provided a liquid ejecting apparatus comprising: a plurality of nozzles, a plurality of nozzles, a plurality of nozzles for ejecting liquid droplets to be measured, And a control section for correcting the discharge condition of the liquid.

According to another aspect of the present invention, there is provided an inspection method for inspecting a dispensing state of a functional liquid from a nozzle, comprising the steps of: capturing, by an imaging section, a plurality of droplets formed on a target object by a functional liquid discharged from the nozzle; For each of the plurality of droplets, performs pattern matching of the entire captured image in the image pickup unit and the entire droplet image having a predetermined shape, and based on the matching result, And a step of measuring a state of formation of the droplet on the basis of a result of imaging by the imaging section with respect to the droplet of the selected measurement target.

According to the present invention, even in the case where the foreign matter exists in the liquid droplet formed on the target object by the functional liquid discharged for inspection, or when the target object is damaged, the discharge state of the functional liquid using the imaging result of the functional liquid droplet It is possible to appropriately correct the discharging condition of the functional liquid.

1 is a schematic diagram showing the outline of the configuration of an inspection apparatus according to the present embodiment.
Fig. 2 is a flowchart for explaining an example of the inspection method according to the present embodiment.
3 is a schematic side view schematically showing the configuration of a functional liquid ejecting apparatus provided with an inspection apparatus according to the present embodiment.
4 is a schematic plan view of the functional liquid ejecting apparatus of Fig.
5 is a schematic diagram showing an outline of the configuration of an inspection apparatus according to a reference embodiment.
6 is a flowchart for explaining an example of the inspection method according to the reference embodiment.
7 is a diagram showing an example of a droplet formed by the functional liquid.
8 is a view for explaining the technical effect of the inspection apparatus of the reference embodiment.
Fig. 9 is a diagram showing an example of a sensed image of a liquid droplet formed by the inspected discharged functional liquid.
10 is a view showing another example of a sensed image of a droplet formed by the functional liquid ejected by the test.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description will be omitted.

First, the configuration of the inspection apparatus according to the present embodiment will be described with reference to Fig. 1 is a schematic diagram showing an outline of the configuration of an inspection apparatus. In addition, the dimensions of the respective components do not always correspond to actual dimensions in order to facilitate understanding of the technique.

The inspection apparatus 1 shown in Fig. 1 has an image pickup section 10 and a control section 11. Fig. The inspection apparatus 1 images the plurality of droplets 21 for inspection formed on the inspection sheet 20 with the imaging section 10 and inspects the discharge state of the functional liquid for forming the droplets 21. [ Each droplet 21 is formed by discharging the functional liquid from the nozzle two or more times a predetermined number of times by an inkjet method. The number of droplets 21 formed on the test sheet 20 is, for example, several tens. The test sheet 20 is an example of a " punched body " according to the present embodiment.

The imaging section 10 is arranged in the direction in which the optical axis of the imaging section 10 is vertical with respect to the main surface of the examination sheet 20 and in the present embodiment, . As the imaging unit 10, various cameras can be used, for example, an area scan camera is used. Then, the image sensing unit 10 picks up an image of the area where the droplets 21 of the inspection sheet 20 are formed. The picked-up image picked up by the pick-up section 10 is outputted to the control section 11. It is preferable that the stage on which the inspection apparatus 1 or the inspection sheet 20 is mounted is configured to be movable so as to capture an image picked up with respect to all the droplets 21 on the inspection sheet 20. [

For example, an LED light source, a halogen light source, and an ultraviolet light source are used as the light source for observing the droplet, and a surface light source of the coaxial incident light or transmitted light is used as the light source. By making the solvent in one state or the droplet evaporated, droplets can be observed more clearly.

The control unit 11 controls the operation of the imaging unit 10 and the like in the inspection apparatus 1. [ The control unit 11 has a measurement unit 11a and a selection unit 11b.

The measuring section 11a measures the state of formation of the droplets 21 based on the imaging result of the imaging section 10. [ For example, the measuring section 11a measures the size and forming position of the selected droplet 21. [

The selecting unit 11b selects the droplet 21 to be measured in the measuring unit 11a among the plurality of droplets 21. [ Specifically, the selecting section 11b selects the entire droplet 21 (the captured image) captured by the imaging section 10 and the entire droplet image having a predetermined shape for each of the plurality of droplets 21 And selects the droplet 21 to be measured in the metering section 11a among the plurality of droplets 21 based on the matching result.

The image of the droplet having the predetermined shape is a complete circle image of the black background (white background in the drawing) when the form of the normal functional droplet is the complete cause of the black background (see Fig. 9A) (Fig. 10A) is a double circle image of concentric white background. The " shape " includes at least a shape and a color. The image of the liquid droplet having the predetermined shape is stored in advance in the inspection apparatus 1, for example.

The pattern matching is performed by, for example, acquiring a grayscale image represented by 256 gradations as a captured image of the droplet 21 and a liquid droplet having the predetermined shape, and calculating the degree of matching for each pixel. For example, when the average value of the calculated degrees of matching exceeds a predetermined value, the selection unit 11b selects the droplet 21 associated with the image as an object to be measured.

Alternatively, instead of the gray scale image represented by 256 tones, a color image in which each color is represented by 256 tones may be used.

As a method of pattern matching, a known method can be arbitrarily adopted. For example, Koji Ikeda, et al., "High-speed template matching by monotonic functionization of normalized correlation", Journal of the Institute of Electronics, Information and Communication Engineers, September 25, 2009, J83-D2, , Pp. 1861-1869 can be employed.

It should be noted that an image having a predetermined shape (hereinafter referred to as a reference image) is previously stored in the above, but it may be selected from among the captured images of a plurality of droplets 21. When the selection is made, for example, the operator manually selects the selection. Alternatively, the control unit 11 may be provided with a reference image selection unit 11c to perform pattern matching different from that described above to automatically select a captured image closest to a perfect circle or a double concentric circle.

The reference image selection unit 11c may change the reference image as follows. That is, based on the reference image manually selected by the operator or the reference image automatically selected by the reference image selecting unit 11c, the reference image selecting unit 11c selects the image of all the droplets 21 For the image, pattern matching is performed with respect to the whole image, and the distribution of the matching degree is obtained. The reference image selector 11c automatically extracts one image from the picked-up images indicating the degree of matching that becomes the peak when there is no peak at the highest matching point in the matching degree distribution, A new reference image may be used. Specifically, when the peak of the matching degree is 1000, and there is a peak in the matching degree distribution where the matching degree is 900, one image is extracted from the captured image having the matching degree 900, A new reference image may be used.

The control unit 11 is, for example, a computer and has a program storage unit (not shown). The program storage section stores the size of the droplet 21 and the size of the droplet 21 based on the program for image processing of the captured image and the program for controlling the operation of the imaging section 10, And a program for calculating the position on the inspection sheet 20 of the inspection sheet 20 are stored. The program storage unit also stores a program for performing pattern matching in the selection unit 11b and the reference image selection unit 11c based on the image-processed data. The program is recorded on a computer-readable storage medium such as a computer readable hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnet optical disk (MO) And may be installed in the control unit 11 from the storage medium.

Next, a method of inspecting the discharging state of the functional liquid, which is carried out using the inspection apparatus 1 configured as described above, will be described with reference to Fig. 2 and with reference to Figs. 9 and 10. Fig. 2 is a flowchart for explaining an example of the inspection method.

When the functional liquid is ejected from the nozzle for inspection and a plurality of droplets 21 are formed on the inspection sheet 20, the imaging section 10 picks up the droplets 21 on the inspection sheet 20 (step S1) . The imaging in the imaging section 10 is performed until all the droplets 21 on the inspection sheet 20 have been imaged. The picked-up image picked up by the image pickup section 10 is outputted to the measurement section 11a and the selection section 11b of the control section 11. [

A plurality of droplets 21 picked up by the image pickup section 10 do not include the foreign object C1 as shown in Fig. 9 and are not damaged in the inspection sheet 20 and the captured images of the droplets 21 It is ideal that the captured images L1 and L2 are double circles of perfect circle or concentric circle, as shown in Fig. 9A or Fig. 10A. However, there is a case where the obtained captured image L1 does not become a complete circle as shown in Figs. 9B and 9C, or a foreign object C1 as shown in Figs. 9C and 9D, As shown in Fig. 10B and Fig. 10C, there is a case in which the second lens L2 does not become a double concentric circle.

Thus, the selecting unit 11b performs pattern matching on the entire image using the reference image with respect to the captured images of each of the plurality of droplets 21, and based on the matching result, among the plurality of droplets 21, Is selected (step S2). For example, the selection unit 11b determines whether or not the droplet 21 corresponding to each captured image is to be measured based on the pattern matching result, and determines whether or not the droplet 21 corresponding to the captured image whose matching degree exceeds the threshold value And the droplet 21 is selected as an object to be measured. As a result, only the droplets 21 corresponding to the captured images (L1, L2) similar to the captured images (L1, L2) shown in Figs. 9A and 10A can be selected / extracted as objects to be measured.

The measuring unit 11a calculates the size and formation position of the droplet 21, that is, the discharge amount of the functional liquid and the discharge deflection, based on the sensed image selected in the selection unit 11b, that is, the droplet 21 (Step S3).

In the functional liquid ejecting apparatus including the inspection apparatus 1, the ejection conditions are adjusted / corrected based on the measurement result of the size and the formation position of the droplet 21 selected by the selection unit 11b. As a result, the functional liquid can be appropriately discharged even when foreign matter exists in the droplet formed on the target object by the discharged functional liquid for inspection, or when the target object is damaged.

In addition, a plurality of nozzles are usually provided for one functional liquid ejection head. Therefore, when inspecting the discharge state of the functional liquid from the nozzles, the functional liquid is discharged from each of the plurality of nozzles, a plurality of droplets are formed for each nozzle, and droplets to be measured are discharged from the nozzles . At this time, the reference image used for pattern matching may be different for each nozzle, or may be common for all nozzles.

The inspection method in the inspection apparatus 1 can be applied even if the inspection sheet is lyophilic or is liquid.

Next, an application example of the inspection apparatus 1 configured as described above will be described with reference to Figs. 3 and 4. Fig. Fig. 3 is a schematic side view schematically showing the configuration of the functional liquid ejecting apparatus provided with the inspection apparatus 1. Fig. 4 is a schematic plan view of the functional liquid ejecting apparatus of Fig. In the following description, the main scanning direction of the substrate (hereinafter referred to as a work) is referred to as the X axis direction, the sub scanning direction perpendicular to the main scanning direction is referred to as Y axis direction, the X axis direction and the vertical direction orthogonal to the Y axis direction And the rotation direction of the rotation in the Z-axis direction and the Z-axis direction is the? Direction.

The functional liquid ejecting apparatus 100 of FIGS. 3 and 4 applies an organic material for forming any one of the organic EL layers (for example, a hole injecting layer, a hole transporting layer, and a light emitting layer) of the organic light emitting diode. The organic material of the present embodiment is a solution in which a predetermined material for forming each layer of the organic EL layer is dissolved in an organic solvent.

The functional liquid ejection apparatus 100 includes an X-axis table 30 extending in the main-scan direction (X-axis direction) and moving the work W in the main scanning direction, And a pair of Y-axis tables 31 and 31 extending in the scanning direction (Y-axis direction). A pair of X-axis guide rails 32 and 32 extend in the X-axis direction on the upper surface of the X-axis table 30, and X-axis linear motors (not shown) ). A Y-axis guide rail 33 extends in the Y-axis direction on the surface of each Y-axis table 31 and a Y-axis linear motor (not shown) is provided on the Y-axis guide rail 33.

A pair of Y-axis tables 31 and 31 are provided with a carriage unit 40 and an image pickup unit 50. [ On the X-axis table 30, a workpiece stage 60 and a discharge inspection unit 70 are provided.

A plurality of, for example, ten carriage units 40 are provided on the Y-axis table 31. Each carriage unit 40 has a carriage plate 41, a carriage rotation operation mechanism 42, a carriage 43, and a functional liquid discharge head 44.

The carriage plate 41 is mounted on the Y-axis guide rail 33 and freely moves in the Y-axis direction by a Y-axis linear motor provided on the Y-axis guide rail 33.

A carriage rotation operation mechanism 42 is provided at the center of the lower surface of the carriage plate 41 so that the carriage 43 can be freely attached and detached to the lower end of the carriage rotation operation mechanism 42. The carriage 43 is freely rotatable in the &thetas; direction by the carriage rotation operating mechanism 42. [

On the lower surface of the carriage 43, a plurality of functional liquid discharge heads 44 are provided. In the present embodiment, for example, three functional liquid ejection heads 44 are provided in the X-axis direction and two liquid ejection heads 44 in the Y-axis direction. A plurality of ejection nozzles (not shown) are formed on the lower surface of the functional liquid ejection head 44, that is, on the nozzle surface, and droplets of the functional liquid are ejected from the ejection nozzles.

The image pickup unit (50) has an image pickup unit (10).

The image pickup section 10 picks up a droplet inspected and ejected onto the inspection sheet 20 of the discharge inspection unit 70. The imaging section 10 is supported on a base 51 provided on the side surface of the Y-axis table 31 on the positive X-axis side of the pair of Y-axis tables 31 and 31, So that it is possible to capture all the droplets ejected.

The workpiece stage 60 is, for example, a vacuum adsorption stage and adsorbs and mounts the workpiece W. The workpiece stage 60 is supported so as to freely rotate in the? Direction by a stage rotation operating mechanism 61 provided on the underside of the workpiece stage 60.

The workpiece carrier 60 and the stage rotation mechanism 61 are supported by a first X-axis slider 62 provided on the lower surface side of the stage rotation mechanism 61. The first X-axis slider 62 is mounted on the X-axis guide rail 32 and freely moves in the X-axis direction by an X-axis linear motor provided on the X-axis guide rail 32. [ The workpiece stage 60 (workpiece W) is also allowed to freely move along the X-axis guide rail 32 in the X-axis direction by the first X-axis slider 62. [

The discharge inspection unit 70 is a unit that receives inspection discharge from the functional liquid discharge head 44. The above-described inspection sheet 20 is disposed in the discharge inspection unit 70.

The discharge inspection unit 70 is mounted on the second X-axis slider 80. The second X-axis slider 80 is mounted on the X-axis guide rail 32 and freely moves in the X-axis direction by an X-axis linear motor provided on the X-axis guide rail 32. [ The discharge inspection unit 70 is also allowed to freely move along the X-axis guide rail 32 in the X-axis direction by the second X-axis slider 80. [

In the functional liquid ejecting apparatus 100 described above, the control unit 11 described above is provided. Therefore, the inspecting apparatus 1 provided inside the functional liquid ejecting apparatus 100 is controlled by the control unit 11. In addition to the program for controlling the inspection apparatus 1, a program for controlling the processing of the substrate in the functional liquid ejection apparatus 100 is also stored in the program storage unit (not shown) of the control unit 11 . Therefore, the control unit 11 also adjusts / controls the ejection condition of the functional liquid ejection head 44 from the nozzles.

The control unit 11 also has a data storage unit (not shown). In the data storage section, for example, drawing data (bitmap data) suitable for the size and position of the liquid droplet formed by the functional liquid ejecting apparatus 100, that is, the desired size and position, are stored in advance. The use of this rendering data will be described later.

Next, the work process performed using the functional liquid ejecting apparatus 100 configured as described above will be described. In the following description, it is assumed that an area on the X-axis direction side with respect to the Y-axis table 31 as a carry-in / out area A1 and a pair of Y-axis tables 31, 31 as the processing area A2 and the area on the X-axis positive side with respect to the Y-axis table 31 as the waiting area A3.

First, the workpiece stage 60 is placed in the loading / unloading area A1 and the workpiece W loaded into the functional liquid discharging device 100 is loaded on the workpiece stage 60 by a transport mechanism do. Subsequently, the X-axis slider 62 moves the workpiece stage 60 from the carry-in / out area A1 to the process area A2. In the processing area A2, droplets are ejected from the functional liquid ejection head 44 to the work W moved downwardly of the functional liquid ejection head 44. The workpiece stage 60 is further moved toward the waiting area A3 so that the front surface of the workpiece W passes under the functional liquid discharge head 44. [ Then, the carriage unit 40 is moved in the Y-axis direction appropriately, and the predetermined pattern is drawn on the work W by reciprocating the work W in the X-axis direction.

After drawing, the workpiece stage 60 is moved to the carry-in / out area A1.

When the workpiece stage 60 moves to the loading / unloading area A1, the workpiece W after the drawing process is carried out of the functional liquid discharging device 100. Subsequently, the next workpiece W is brought into the functional liquid ejection apparatus 100. [

As described above, the inspecting apparatus 1 inspects the discharging state of the functional liquid discharged from the functional liquid discharging head 44 while the work W is carried in or out or before the discharging. More specifically, first, the second X-axis slider 80 moves the discharge inspection unit 70 from the waiting area A3 to the processing area A2. The inspection sheet 20 of the discharge inspection unit 70 is disposed below the functional liquid discharge head 44 and the functional liquid is discharged from the nozzle head 54 to the surface of the inspection sheet 20 (Plural times) to form the inspection discharge droplets 21 (step S3). A plurality of nozzles are provided in the functional liquid ejection head 44 as described above, and a plurality of droplets 21 are formed per nozzle.

Thereafter, the discharge inspection unit 70 is moved to the X-axis positive direction side, and the inspection sheet 20 of the discharge inspection unit 70 is disposed below the image pickup unit 10. [ Then, a plurality of droplets (21) are imaged by the imaging section (10). The picked-up picked-up image is outputted to the selection unit 11b and the measurement unit 11a of the control unit 11. [

The selection unit 11b performs pattern matching on the entire image using the reference image for the captured images of the plurality of droplets 21 formed by the corresponding nozzles for each nozzle. Then, based on the matching result, the selecting unit 11b selects the droplet 21 to be measured in the measuring unit 11a among the plurality of droplets 21. [

The measurement unit 11a measures the size of the droplet 21 and the position of the droplet 21 on the inspection sheet 20 based on the image of the droplet selected for the selected droplet 21. [ In this manner, on the basis of the state of formation of the droplets 21, the discharge state of the functional liquid from each nozzle is inspected. Further, normally, in the selecting section 11b, two or more droplets 21 are selected from a plurality of droplets 21.

When the size and position of two or more droplets 21 are measured for each nozzle in the measuring section 11a, the control section 11 calculates the average value of the size and position of the droplet 21 for each nozzle. The controller 11 compares the measured data of the average of the sizes of the droplets 21 and the average of the positions and the normal data of the sizes and positions of the droplets stored in advance for each of the nozzles. When the measurement data is deviated from the normal data, the control unit 11 sets the ejection condition of the functional liquid to the functional liquid ejection head 100 so that the functional liquid ejection head 44 of the functional liquid ejection apparatus 100 ejects the functional liquid in a normal form Adjust. The inspection of the discharging state of the functional liquid and the discharging condition of the functional liquid may be performed for each substrate W or for every predetermined number of the substrates W. [

According to the embodiment described above, since the inspection apparatus 1 is provided in the functional liquid ejection apparatus 100, the functional liquid ejection head 44 is provided with the functional liquid ejection head 44, And the discharging condition of the functional liquid can be adjusted by feedback control. Therefore, it is possible to suppress the defective discharge of the functional liquid in the functional liquid ejecting apparatus 100, appropriately control the size of the functional liquid (that is, the weight of the functional liquid) and the position of the functional liquid discharged onto the substrate W, An organic material can be suitably applied to the substrate W. [

The inspection of the discharging condition of the functional liquid by the inspection apparatus 1 and the adjustment of the discharging condition of the functional liquid in the functional liquid discharging apparatus 100 are the same as the above- But it may be performed before the coating process.

The layout of the functional liquid ejecting apparatus 100 according to the above embodiment is not limited to the layouts shown in Figs. 3 and 4, and can be arbitrarily set.

Although the functional liquid ejecting apparatus 100 for forming the organic EL layer of the organic light emitting diode has been described as an application example of the inspection apparatus 1, the application example of the inspection apparatus 1 is not limited to this. For example, the inspection apparatus 1 may be applied to a substrate processing apparatus for applying a color resist.

(Reference Embodiment)

First, the configuration of the inspection apparatus according to the embodiment of the reference will be described with reference to Fig. 5 is a schematic diagram showing the outline of the configuration of the inspection apparatus. In addition, the dimensions of the respective components do not always correspond to the actual dimensions in order to facilitate understanding of the technique.

The inspection apparatus 1 'in Fig. 5 has an image pickup section 10 and a control section 11'. The inspection apparatus 1 'images the plurality of droplets 21 for inspection formed on the inspection sheet 20 with the imaging section 10 and inspects the discharge state of the functional liquid forming the droplets 21 . Each droplet 21 is formed by discharging the functional liquid from the nozzle two or more times a predetermined number of times by an inkjet method. The number of droplets 21 formed on the test sheet 20 is, for example, several tens.

The imaging section 10 is arranged in the direction in which the optical axis of the imaging section 10 is vertical with respect to the main surface of the examination sheet 20 and is disposed vertically above the examination sheet 20 in the present embodiment. As the imaging section 10, various cameras can be used, for example, an area scan camera is used. Then, the image sensing unit 10 picks up an image of the area where the droplets 21 of the inspection sheet 20 are formed. The picked-up image picked up by the pick-up section 10 is outputted to the control section 11 '. It is preferable that a stage on which the inspection apparatus 1 'or the inspection sheet 20 is mounted is configured to be movable so as to capture a picked-up image of all the droplets 21 on the inspection sheet 20.

For example, an LED light source, a halogen light source, and an ultraviolet light source are used as the light source for observing the droplet, a surface light source of the coaxial incident light or transmitted light, a state in which the solvent in the droplet is impregnated in the test sheet, By making the solvent in the droplet evaporate, the droplet can be observed more clearly.

The control unit 11 'controls the operation of the imaging unit 10 and the like in the inspection apparatus 1'. The control unit 11 'has a measurement unit 11a and a selection unit 11b'.

The measuring section 11a measures the state of formation of the droplets 21 based on the imaging result of the imaging section 10. [ For example, the measuring section 11a measures the size and forming position of the selected droplet 21. [

The selection unit 11b 'selects the droplet 21 to be measured in the measurement unit 11a among the plurality of droplets 21 and selects the droplet 21 to be measured using the imaging result in the imaging unit 10. [ (21) based on the formation state of the droplet (21). For example, the selection unit 11b 'selects the droplet 21 to be measured based on the shape of the droplet 21. More specifically, the selection unit 11b 'performs pattern matching based on a predetermined image with respect to the image taken by the imaging unit 10 of each of the plurality of droplets 21, and based on the matching result, The target droplet 21 is selected. The predetermined image may be a droplet image of a predetermined appropriate shape (e.g., a complete circle), and the predetermined image may be stored in advance in the inspection apparatus 1, You can also choose. For example, the operator may manually select the photographed image, or may perform pattern matching different from the above to automatically select the photographed image closest to the complete circle.

As a method of pattern matching, a known method can be arbitrarily adopted.

The control unit 11 'is, for example, a computer and has a program storage unit (not shown). The program storage section stores the size of the droplet 21 and the size of the droplet 21 based on the program for image processing of the captured image and the program for controlling the operation of the imaging section 10, And a program for calculating the position on the inspection sheet 20 of the inspection sheet 20 are stored. The program storage unit also stores a program for performing pattern matching in the selection unit 11b 'based on the image-processed data. The program is recorded in a computer-readable storage medium such as a computer readable hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnet optical disk (MO) , And may be installed in the control unit 11 'from the storage medium.

Next, a method of inspecting the discharging state of the functional liquid, which is carried out using the inspection apparatus 1 'configured as described above, will be described with reference to Figs. 6 and 7. Fig. Fig. 6 is a flowchart for explaining an example of the inspection method. 7 is a diagram showing an example of a droplet formed by the functional liquid.

When the functional liquid is ejected from the nozzle for inspection and a plurality of droplets 21 are formed on the inspection sheet 20, the imaging section 10 picks up the droplets 21 on the inspection sheet 20 (step S1) . The imaging in the imaging section 10 is performed until all the droplets 21 on the inspection sheet 20 have been imaged. The picked-up image picked up by the image pickup section 10 is outputted to the measurement section 11a and the selection section 11b 'of the control section 11'.

It is ideal that the plurality of droplets 21 captured by the imaging section 10 are all circular in plan view like the droplets 21 in Fig. 7A. However, the plurality of droplets 21 may have the same shape as that of the droplets 21 of Fig. 7 (b) and the notches at the outer periphery of the circle as viewed in plan and / And a shape in which an ear-shaped portion is provided on the outer periphery of the bore circle.

Thus, the selecting unit 11b 'performs pattern matching on the shape of the droplet 21 on the basis of a predetermined image stored in advance in the inspection apparatus 1', on the captured image of each of the plurality of droplets 21 And selects the droplet 21 to be measured (step S12). For example, the selection unit 11b 'determines whether or not the droplet 21 corresponding to each photographed image is to be measured based on the pattern matching result regarding the shape of the droplet 21, and if the matching degree is a threshold value And the droplet 21 corresponding to the overshot image is selected as the measurement target. As a result, only the droplet 21 having a shape close to the droplet 21 in FIG. 7A can be selected / extracted as an object to be measured.

The measuring unit 11a calculates the size and formation position of the droplet 21, that is, the discharge amount of the functional liquid, and the discharge deflection (droplet discharge amount) based on the sensed image selected in the selection unit 11b ' (Step S3).

In the functional liquid ejecting apparatus including the inspection apparatus 1 ', the ejection conditions are adjusted / corrected based on the measurement result of the size and formation position of the droplet 21 selected by the selection unit 11b'. Thus, the functional liquid can be appropriately discharged.

8 is a view for explaining the effect of the inspection apparatus 1 ', wherein each drawing shows the distribution of the droplets 21, the horizontal axis indicates the area, and the vertical axis indicates the frequency.

As a method of extracting the droplets 21 having a shape close to that of Fig. 7A among the plural droplets 21, a method of extracting based on the shape of the droplet 21 as described above, The way is thought.

The droplet 21 having the shape as shown in FIG. 7B has a smaller area than the droplet 21 having the shape as shown in FIG. 7A, and the droplet 21 having the shape as shown in FIG. The area is larger than the droplet 21. Therefore, as a method of extracting the droplet 21 having a shape close to Fig. 7A, a method of extracting based on the area of the droplet 21, more specifically, a method of extracting the droplet 21 having an area larger than a predetermined value, A method of excluding the droplet 21 having an area smaller than the fixed value from the object of measurement may be considered.

The distribution P100 of the droplets 21 including both the droplets 21 having the shape shown in Fig. 7A, the droplets 21 having the shape shown in Fig. 7B, and the droplets 21 having the shape shown in Fig. , And if it is a normal distribution, it is considered that it is possible to exclude the droplets 21 having the shapes shown in Figs. 7B and 7C from the object of measurement, even if the object to be measured is selected based on the above-mentioned area.

However, the distribution of the droplets 21 including the droplets 21 in the shape of Fig. 7A, the droplets 21 in the shape of Fig. 7B, and the droplets 21 in the shape of Fig. (P1) is not a normal distribution as shown in Fig. 8B. The distribution P13 of the droplets 21 in the shape of Fig. 7A, the distribution P13 of the area of the droplets 21 in the shape of Fig. 7B, and the distribution P12 of the droplets 21 in the shape of Fig. , And the entire distribution P1 is obtained by superposing distributions representing these normal distributions.

Therefore, it is impossible to completely exclude the droplet 21 having the shape as shown in Fig. 7B or the droplet 21 having the shape as shown in Fig. 7C even if the exclusion is performed based on the area.

On the other hand, by extracting based on the shape of the droplet 21 as in the inspection method according to the present embodiment, only the droplet 21 showing the distribution P11 in Fig. 8B, that is, the droplet 21 having the shape of Fig. Can be extracted.

Therefore, in the inspection method according to the present embodiment, the formation state can be measured only for the droplet 21 having the shape shown in Fig. 7A, and therefore, the discharge condition of the functional liquid can be appropriately corrected based on the measurement result.

In addition, a plurality of nozzles are usually provided for one functional liquid ejection head. Therefore, when inspecting the discharging state of the functional liquid from the nozzles, the functional liquid is discharged from each of the plurality of nozzles, a plurality of droplets are formed for each nozzle, and measurement is performed based on the shape of the liquid droplets It is good to select the target droplet. At this time, the predetermined image used for pattern matching may be different for each nozzle, or may be common for all nozzles.

A method of determining the droplet 21 to be measured out of a plurality of droplets 21 based on the size of the droplet is a method in which the entire distribution of the droplet 21 shows a normal distribution And only the droplets 21 having the same shape as the droplet 21 are formed).

Although the embodiments of the present invention have been described above, the present invention is not limited to these examples. It will be understood by those skilled in the art that it is within the technical scope of the claims and that various changes and modifications are obvious to those skilled in the art and that they are obviously also within the technical scope of the present invention.

1: Inspection apparatus 10: Imaging section
11a: Measuring section 11b:
11c: Reference image selection unit 11:
20: inspection sheet 21: droplet
44: functional liquid ejection head 100: functional liquid ejection device

Claims (6)

An inspection apparatus for inspecting a discharge state of a functional liquid from a nozzle,
An imaging unit for imaging a plurality of droplets formed on the object by the functional liquid discharged from the nozzle;
A measurement unit for measuring a state of formation of the liquid droplet based on an imaging result of the imaging unit;
Performing pattern matching of all of the captured images in the imaging section with respect to each of the plurality of droplets and the entire image of the droplet having a predetermined shape, and based on the matching result, A selection unit for selecting a target droplet
And an inspection device for inspecting the inspection device.
The method according to claim 1,
And a reference image selection unit that selects an image of the liquid droplet having the predetermined shape from among the captured images of the plurality of liquid droplets picked up by the image pickup unit.
3. The method according to claim 1 or 2,
Wherein the captured image and the liquid droplet image having the predetermined shape are gray scale images represented by 256 gray scales.
3. The method according to claim 1 or 2,
Wherein the captured image and the liquid droplet image having the predetermined shape are color images each of which is represented by 256 gradations.
The plurality of nozzles
The inspection apparatus according to claim 1 or 2,
And a control unit for correcting a discharging condition of the functional liquid based on a measurement result of the measuring unit with respect to a liquid droplet selected as a liquid droplet to be measured by the measuring unit for each of the nozzles,
And a control unit for controlling the operation of the functional liquid ejecting apparatus.
An inspection method for inspecting a discharge state of a functional liquid from a nozzle,
A step of picking up a plurality of droplets formed on the object by the functional liquid discharged from the nozzle,
Performing pattern matching on the entire captured image in the image pickup unit and the entire droplet image having a predetermined shape for each of the plurality of droplets, and based on the matching result, A step of selecting,
A step of measuring a state of formation of the droplet on the basis of the imaging result of the imaging section for the droplet of the selected measurement target
Wherein the method comprises the steps of:

Images