Printing apparatus having multiple nozzle heads and arrangement method for multiple nozzle tips

Abstract

The present application relates to a printing device having a plurality of nozzle heads and an arrangement method of a plurality of nozzle tips, the printing device having a plurality of nozzle heads according to the present application is characterized by comprising: a first nozzle head configured in one side region within a work region on a substrate, provided with a first nozzle tip capable of ejecting ink and a first moving portion capable of moving the first nozzle tip; a second nozzle head configured in the other side region within the work region on the substrate, provided with a second nozzle tip capable of ejecting ink and a second moving portion capable of moving the second nozzle tip; and a first camera configured on the upper side of the work region for simultaneously observing the first nozzle tip and the second nozzle tip.

Description

TECHNICAL FIELD

[0001] The present application relates to a printing device having a plurality of nozzle heads and a method of arranging a plurality of nozzle tips, and more particularly, to a printing device having a plurality of nozzle heads capable of improving printing speed and productivity by independently controlling a plurality of nozzle heads, respectively, and being configured to share a camera by a plurality of nozzles, thereby enabling a compact structure. BACKGROUND

[0002] In general, an inkjet device that ejects a fluid in the form of a droplet has been mainly applied to an inkjet printer in the past, but has recently been widely applied to high-tech industries such as a manufacturing process of a display, a manufacturing process of a printed circuit board, and a manufacturing process of a DNA chip.

[0003] The inkjet device is a device for ejecting a droplet from an ink in a fluid state, and is classified into two major types of a heating type and a piezoelectric type according to a method of ejecting a droplet, and recently, in order to ultra-fine printing, an electrodynamic type electrostatic inkjet printer has been widely used.

[0004] The electrostatic inkjet printer ejects ink using electrostatic force due to a potential difference generated by applying a voltage between a nozzle and a substrate. As is well known, the electrostatic inkjet printer ejects a droplet or performs continuous inkjet using force by which a liquid surface is pulled by electrostatic force, and thus, unlike the inkjet printer of the other type in the past, has various advantages such as enabling nano-level patterning, ejecting high-viscosity ink, and generating uniform droplets.

[0005] However, the printing device of the related art has a problem of low productivity because a single nozzle is used to perform a printing process.

[0006] In order to improve such a problem, when a plurality of nozzles independently driven are arranged in parallel, productivity can be improved, but there is a problem of a great increase in manufacturing cost and an increase in volume of the device.

[0007] Patent Document 0001: Korean Patent Publication No. 10-2017-0072748 SUMMARY

[0008] Therefore, the present application has been made to solve the above-mentioned problems, and it is an object of the present application to provide a printing device having a plurality of nozzle heads capable of improving printing speed and productivity by independently controlling a plurality of nozzle heads, respectively, and being configured to share a camera by a plurality of nozzles, thereby enabling a compact structure.

[0009] Furthermore, it is an object of the present application to provide a method of arranging a plurality of nozzle tips that can set reference positions of a plurality of nozzle tips and arrange positions using a shared camera, and thus can accurately control positions of a plurality of nozzle tips that are independently driven.

[0010] The object is achieved by a printing apparatus having a plurality of nozzle heads according to the present application, which includes a first nozzle head configured in one side region within a work region on a substrate, having a first nozzle tip capable of ejecting ink and a first moving portion capable of moving the first nozzle tip; a second nozzle head configured in another side region within the work region on the substrate, having a second nozzle tip capable of ejecting ink and a second moving portion capable of moving the second nozzle tip; and a first camera configured on an upper side of the work region for simultaneously observing the first nozzle tip and the second nozzle tip.

[0011] Here, the printing apparatus preferably further includes a second camera configured on an upper side of the work region in a tilt direction toward a lower side for simultaneously observing the first nozzle tip and the second nozzle tip.

[0012] Furthermore, it preferably further includes a control portion for controlling driving of the first moving portion and the second moving portion based on images obtained from the first camera and the second camera, thereby respectively controlling positions of the first nozzle tip and the second nozzle tip.

[0013] Furthermore, it is preferable that, in order to eject ink by an electrohydrodynamic method, the first nozzle head and the second nozzle head respectively include a high voltage application portion capable of applying a voltage to ink.

[0014] Furthermore, it is preferable that the first nozzle head and the second nozzle head are configured apart in a first axis direction with the work region as a center, and the second camera is configured apart from the first camera in a second axis direction crossing the first axis.

[0015] Furthermore, it is preferable that the first nozzle tip and the second nozzle tip are configured in a tilt with a tilt with respect to the first axis.

[0016] Furthermore, it is preferable that the second camera is configured in a tilt with a tilt with respect to the second axis.

[0017] Furthermore, it is preferable that the first moving portion and the second moving portion are configured to be capable of at least three-axis movement.

[0018] Another object of the present application is achieved by a method of arranging a plurality of nozzle tips, the method comprising: a first nozzle alignment step of setting a reference position of a first nozzle tip capable of ejecting ink into a work area, by an image of a first camera observing the work area from an upper side of the work area and an image of a second camera observing the work area from an upper side of a side of the work area toward a lower side in a slanting direction; a second nozzle alignment step of setting a reference position of a second nozzle tip capable of ejecting ink into the work area, by the images of the first camera and the second camera; a substrate position detection step of detecting a position of a substrate based on the image of the second camera; and a printing preparation step of positioning the first nozzle tip and the second nozzle tip at a printing position on the substrate.

[0019] Here, it is preferable that the reference position is set by positioning the tip end of the first nozzle tip or the tip end of the second nozzle tip at the center of the field of view (FOV) of the second camera, and then positioning the tip end of the first nozzle tip or the tip end of the second nozzle tip at the center of the field of view (FOV) of the first camera.

[0020] Further, it is preferable that after the first nozzle alignment step and the second nozzle alignment step, a step of moving the first nozzle tip and the second nozzle tip to specified positions each separated from the reference position by a prescribed distance is performed.

[0021] Further, it is preferable that the specified positions are positions at which the first nozzle tip and the second nozzle tip are separated from each other in the horizontal direction with the reference position as the center.

[0022] Further, it is preferable that the specified positions are positions separated from the position of the substrate detected after autofocusing by a distance specified in advance in the third axis direction.

[0023] Further, it is preferable that in the step of moving to the specified positions, the positions in the third axis direction of the first nozzle tip and the second nozzle tip are adjusted by a drive unit for moving the printing device including the first nozzle tip, the second nozzle tip, the first camera, and the second camera simultaneously.

[0024] Further, it is preferable that in the printing preparation step, the positions in the third axis direction of the first nozzle tip and the second nozzle tip are adjusted by a drive unit for moving the printing device including the first nozzle tip, the second nozzle tip, the first camera, and the second camera simultaneously.

[0025] Further, it is preferable that the substrate position detecting step detect the height of the substrate using an image of the nozzle tip included in the image obtained by the second camera and a mirror image of the nozzle tip reflected on the substrate.

[0026] According to the present application, there is provided a printing apparatus having a plurality of nozzle heads, which can improve printing speed and productivity by independently controlling the plurality of nozzle heads, and is configured to share a camera by the plurality of nozzle heads, thereby enabling a compact structure.

[0027] Further, there is provided a method of arranging a plurality of nozzle tips, which can arrange positions using a reference position of the plurality of nozzle tips set using a shared camera, thereby enabling accurate control of positions of the plurality of nozzle tips independently driven. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a perspective view of the printing apparatus having a plurality of nozzle heads according to the present application.

[0029] Figure 2 is a front view of the printing apparatus having a plurality of nozzle heads according to the present application.

[0030] Figure 3 is a side view of the printing apparatus having a plurality of nozzle heads according to the present application.

[0031] Figure 4 is an image representing a first camera image.

[0032] Figure 5 is an image representing a second camera image.

[0033] Figure 6 is a diagram representing a process of a first nozzle alignment step.

[0034] Figure 7 is a diagram representing a second camera image.

[0035] Figure 8 is a diagram representing a first camera image.

[0036] Figure 9 is a diagram representing a step of moving the first nozzle tip to a designated position after the first nozzle alignment step.

[0037] Figure 10 is a diagram representing a process of a second nozzle alignment step.

[0038] Figure 11 is a diagram representing a step of moving the second nozzle tip to a designated position after the second nozzle alignment step.

[0039] Figure 12is a diagram showing a step of detecting a substrate position based on a second camera image.

[0040] Figure 13 is a diagram showing a print preparation step.

[0041] BRIEF DESCRIPTION OF DRAWINGS

[0042] 110: first nozzle head

[0043] 111: first nozzle tip

[0044] 112: first moving section

[0045] 113: first high voltage application section

[0046] 120: second nozzle head

[0047] 121: second nozzle tip

[0048] 122: second moving section

[0049] 123: second high voltage application section

[0050] 130: first camera

[0051] 140: second camera

[0052] 150: support

[0053] S: substrate

[0054] P1: reference position

[0055] P2: specified position DETAILED DESCRIPTION

[0056] Before the present application is described, it is to be understood that the application is not limited in its application to the details of the construction and the arrangement of the components set forth in the following description the description is intended to cover all alternatives, modifications, and equivalents as may be included within the scope of the application and further intended to cover all equivalents thereof.

[0057] Hereinafter, a printing apparatus having a plurality of nozzle heads according to a first embodiment of the present application will be described in detail with reference to the drawings.

[0058] In the drawings, Figure 1 is a perspective view of a printing apparatus having a plurality of nozzle heads according to the present application, Figure 2 is a front view of a printing apparatus having a plurality of nozzle heads according to the present application, Figure 3 is a side view of a printing apparatus having a plurality of nozzle heads according to the present application, Figure 4 is an image showing a first camera image, Figure 5 is an image showing a second camera image.

[0059] A printing apparatus having a plurality of nozzle heads according to the present application shown in the drawing includes a first nozzle head 110, a second nozzle head 120, a first camera 130, a second camera 140, and a control section.

[0060] First, although the description is made in the present embodiment with reference to an electrohydrodynamic type electrostatic inkjet printer used for ultra-fine printing, the present application is not limited thereto, and the technical idea thereof can be applied to other types of printers that eject ink from a nozzle. Further, although the description is made in the present embodiment with the first axis as the X axis, the second axis as the Y axis, and the third axis as the Z axis, the present application is not limited thereto.

[0061] The first nozzle head 110 includes a first nozzle tip 111 that can eject ink onto a substrate in a side region of a work region, a first moving section 112 that can move the first nozzle tip 111, and a first high voltage application section 113 that can apply a high voltage to an electrode formed inside the first nozzle tip 111 in order to eject ink by an electrohydrodynamic method.

[0062] The first nozzle tip 111 has a chamber that houses ink inside, and is used to eject ink onto a substrate. Such a first nozzle tip 111 is arranged obliquely with respect to the first axis so as to be observable in real time by the first camera 130 that photographs an image from the upper side toward the lower side of the work region, and the second camera 140 that photographs an image from the upper side toward the lower side of the work region in an oblique direction. In addition, although the first nozzle tip 111 is illustrated as a cartridge that is detachably replaced in the drawing of the present embodiment, the present application is not limited thereto.

[0063] The first moving section 112 can be configured to achieve three-axis movement between the first nozzle tip 111 and a base, and can be configured to include a first axis linear drive mechanism, a second axis linear drive mechanism, and a third axis linear drive mechanism. The structure of such a first moving section 112 corresponds to a well-known technology, and thus a detailed description thereof is omitted. In addition, although the description is made in the present embodiment with the first moving section 112 having three degrees of freedom, the present application is not limited thereto, and can be changed to various forms as needed, such as being configured to have six degrees of freedom in order to achieve movement such as yaw, pitch, and roll.

[0064] The first nozzle tip 111 can be configured by a nozzle of a capillary type of a conductive or non-conductive material widely used in an electrostatic inkjet printer, and the outer diameter of the nozzle tip can be 1 to 300 μm and the inner diameter can be 0.5 to 250 μm. The outer diameter and the inner diameter of the nozzle tip can be changed according to the physical properties of the ink or the printing environment, etc. When a high voltage is applied to an electrode provided on the side of the first nozzle tip 111 through the first high voltage applying part 113, an electric field is formed between the electrode and the substrate. At this time, the polarity of the electrode and the substrate can have opposite polarities to each other, or the substrate can be grounded. Due to the high voltage applied to the electrode, an electric field is formed in the direction from the electrode toward the substrate, and the ink can be finely jetted using the electrostatic force generated by the electric field. The printing principle of such an electrostatic inkjet printer corresponds to a well-known technology, and thus a detailed description thereof will be omitted.

[0065] The second nozzle head 120 includes a second nozzle tip 121 which can jet the ink onto the substrate on the other side of the work area, a second moving part 122 which can move the second nozzle tip 121, and a second high voltage applying part 123 which can apply a high voltage to an electrode formed inside the second nozzle tip 121 in order to jet the ink by an electrohydrodynamic method.

[0066] The second nozzle tip 121, the second moving part 122, and the second high voltage applying part 123 configuring the second nozzle head 120 are configured in the same form as the first nozzle tip 111, the first moving part 112, and the first high voltage applying part 113 of the first nozzle head 110, and thus a detailed description thereof will be omitted.

[0067] The first nozzle head 110 and the second nozzle head 120 are disposed apart from each other in the first axis direction and are disposed in a symmetrical form with the first nozzle head 110 as a center.

[0068] The first camera 130 is disposed to photograph the work area toward the lower side in the vertical direction on the upper side of the work area. When the work area is photographed in the inclined direction, image distortion can occur, and if the work area is photographed on the vertical upper portion of the substrate, an image of the process of the ink impact and the pattern shape formed on the substrate by the impact of the ink can be obtained without distortion.

[0069] The second camera 140 is disposed to photograph the work area in the inclined direction on the upper portion of one side of the work area. That is, the second camera 140 is disposed apart from the first camera 130 in the second axis direction intersecting the first axis and is inclined to have an inclination with respect to the second axis. When the second camera 140 is inclined and disposed as such, the images of the first nozzle tip 111 and the second nozzle tip 121 and the mirror images of the first nozzle tip 111 and the second nozzle tip 121 reflected to the substrate can be simultaneously confirmed through the image of the second camera 140.

[0070] The field of view (FOV) of the first camera 130 and the second camera 140 is set to be able to simultaneously observe the first nozzle tip 111 and the second nozzle tip 121 within the work area. Here, the field of view (FOV) means the size of the image photographed by a camera when it photographs an object, that is, the range of the object that can be seen by the camera. For example, the FOV of the first camera 130 can be set to 425 x 454 μm, and the FOV of the second camera 140 can be set to 800 x 600 μm, which is relatively larger than the FOV of the first camera 130. Thus, in a state in which the positions of the first nozzle tip 111 and the second nozzle tip 121 are recognized through the image of the second camera 140, the focus of the images of the first nozzle tip 111 and the second nozzle tip 121 can be set through the image of the first camera 130, and the reference positions P1 of the first nozzle tip 111 and the second nozzle tip 121 can be set.

[0071] Further, in order to accurately set the reference positions P1 of the first nozzle tip 111 and the second nozzle tip 121, the depth of field (DOF) of the first camera 140 can be set to be less than or equal to ±1.6 μm, and the depth of the DOF region can be appropriately changed according to the lens characteristics applied to the first camera 140. The reference positions P1 of the first nozzle tip 111 and the second nozzle tip 121 can be set at the optimal focus positions within the DOF region of the first camera 140 as described above. That is, if the first nozzle tip 111 and the second nozzle tip 121 are out of the DOF region of the first camera 130, the image becomes blurred and the image contrast is lowered, and thus it is not possible to visualize and detect the first nozzle tip 111 and the second nozzle tip 121 within the image of the first camera 130. Thus, the positions of the first nozzle tip 111 and the second nozzle tip 121 can be adjusted to the sub-micron level within the DOF region of the first camera 130 to find the optimal focus positions, and the optimal focus positions can be set as the reference positions P1 of the first nozzle tip 111 and the second nozzle tip 121.

[0072] Further, the pixel resolution of the first camera 130 can be set to 0.1725 μm / pixel, and the pixel resolution of the second camera 140 can be set to 0.625 μm / pixel. That is, since the magnification of the first camera 130 is set to be higher than that of the second camera 140, the pixel resolution of the first camera 130 can be set to be relatively lower than the pixel resolution of the second camera 140.

[0073] The control section is configured to control driving of the first and second moving sections 112 and 122 based on images obtained from the first and second cameras 130 and 140 to control positions of the first and second nozzle tips 111 and 121, respectively. That is, the control section can receive images obtained by the first and second cameras 130 and 140, analyze images of the first and second nozzle tips 111 and 121 shown in the images, and then provide driving signals for moving the first and second nozzle tips 111 and 121 to the first and second moving sections 112 and 122.

[0074] In addition, the first and second nozzle heads 110 and 120, the first and second cameras 130 and 140 are provided on a bracket 150 which can be configured to be movable in a third axis direction by an additional driving section (not shown). The printing apparatus having a plurality of nozzle heads according to the present application configured as described above can form a pattern on a substrate while simultaneously observing the first and second nozzle tips 111 and 121 which are independently movable, respectively, by the first and second cameras 130 and 140, and thus can improve printing speed and productivity, and can achieve a compact structure by configuring a plurality of nozzles to share a camera.

[0075] Next, a method of arranging a plurality of nozzle tips according to the present application will be described.

[0076] In the drawings, Figure 6 is a diagram showing a process of a first nozzle alignment step, Figure 7 is a diagram showing a second camera image, Figure 8 is a diagram showing a first camera image, Figure 9 is a diagram showing a step of moving the first nozzle tip to a designated position after the first nozzle alignment step, Figure 10 is a diagram showing a process of a second nozzle alignment step, Figure 11 is a diagram showing a step of moving the second nozzle tip to a designated position after the second nozzle alignment step, Figure 12 is a diagram showing a step of detecting a substrate position based on a second camera image, Figure 13 is a diagram showing a printing preparation step.

[0077] The method of arranging a plurality of nozzle tips according to the present application includes a first nozzle alignment step S110, a first nozzle moving step S120, a second nozzle alignment step S130, a second nozzle moving step S140, a substrate position detecting step S150, and a printing preparation step S160.

[0078] First, as Figures 6 to 8As shown, the first nozzle alignment step S110 can set a reference position P1 (relative coordinate origin) of the first nozzle tip 111 that can jet ink into the work area, using the first camera 130 that observes the work area from the third axis Z direction side of the work area and the second camera 140 that observes the work area from the second axis Y direction side of the work area.

[0079] First, as shown in FIG. 2, the first, second, and third axis (X, Y, and Z) direction positions of the first nozzle tip 111 are adjusted so that the end portion of the first nozzle tip 111 is located at the FOV center of the image C2 of the second camera 140. Specifically, after the position of the first nozzle tip 111 is adjusted so that the end portion of the first nozzle tip 111 is located at the FOV center of the image C2 of the second camera 140, the position of the first nozzle tip 111 is adjusted so that the end portion of the first nozzle tip 111 moves to the best focus position that is most clearly visible within the DOF region of the second camera 140. Figure 7 Then, as shown in FIG. 3, the first, second, and third axis (X, Y, and Z) direction positions of the first nozzle tip 111 are adjusted so that the end portion of the first nozzle tip 111 is located at the FOV center of the image C1 of the first camera 130, and as shown in FIG. 4, the position of the first nozzle tip 111 is adjusted so that the end portion of the first nozzle tip 111 moves to the best focus position that is most clearly visible within the DOF region of the first camera 130, and after this position is set as the reference position P1 (relative coordinate origin) of the first nozzle tip 111.

[0080] Figure 8 Figure 6 That is, after the first, second, and third axis (X, Y, and Z) direction positions of the first nozzle tip 111 are adjusted to the FOV center and the best focus position of the image C2 of the second camera 140, the first, second, and third axis (X, Y, and Z) direction positions of the first nozzle tip 111 are adjusted to the FOV center and the best focus position of the image C2 of the first camera 130 that has a higher magnification than the second camera 140, so that the setting accuracy of the reference position P1 can be improved.

[0081] Furthermore, the reference positions P1 of the first nozzle tip 111 and the second nozzle tip 121 are set by the positioned first camera 130 and the second camera 140, respectively, so that the reference position P1 of the first nozzle tip 111 and the reference position P1 of the second nozzle tip 121 can be set at the same location.

[0082]

[0083] At this time, the first camera 130 is in a fixed state in which the posture cannot be changed, so it is preferable to perform a process of aligning the FOV center of the image C2 of the second camera to the center of the image C1 of the first camera before the reference position P1 is set.​​​

[0084] As shown in FIG. 1, the first nozzle alignment step S110 is performed to set the reference position P1 of the first nozzle tip 111 (relative coordinate origin) and the second nozzle alignment step S130 is performed to set the reference position P1 of the second nozzle tip 121 (relative coordinate origin). Figure 9 As shown in FIG. 2, in the first nozzle moving step S120, the position of the first nozzle tip 111 separated from the reference position P1 by a predetermined distance in the first axis X direction is set as the designated position P2, and then the first nozzle tip 111 is moved to an arbitrary position away from the reference position P1 in order to perform the second nozzle alignment step S130.

[0085] As shown in FIG. 3, in the second nozzle alignment step S130, the first axis X and second axis Y direction positions of the second nozzle tip 121 are adjusted so that the end portion of the second nozzle tip 121 is located behind the center of the image C2 of the second camera 140 and the image C1 of the first camera 130, respectively, the third axis Z direction position of the second nozzle tip 121 is adjusted so that the end portion of the second nozzle tip 121 is moved to the best focus position of the image C1 of the first camera 130, and the reference position P1 (relative coordinate origin) of the second nozzle tip 121 is set. This second nozzle alignment step S130 is implemented by the same procedure as the first nozzle alignment step S110, and thus a detailed description is omitted. Figure 10 As shown in FIG. 4, in the second nozzle moving step S140, the position of the second nozzle tip 121 separated from the reference position P1 in the first axis X direction is set as the designated position P2. It is preferable that the designated positions P2 be set to positions separated from each other in the first axis X direction with the reference position P1 as the center, so that interference of the first nozzle tip 111 and the second nozzle tip 121 can be prevented. After the designated positions P2 of the second nozzle tip 121 are set, the second nozzle tip 121 can be moved to an arbitrary position away from the reference position P1 in order to position the substrate S on the stage.

[0086] Figure 11 In addition, after the substrate S is mounted on the stage, the first nozzle tip 111 and the second nozzle tip 121 are moved to the designated positions P2, respectively.

[0087] At this time, it is preferable that the third axis Z direction positions of the designated positions P2 be set to positions separated from the substrate S in the third axis Z direction so as to prevent the first nozzle tip 111 and the second nozzle tip 121 from colliding with the substrate S while the first nozzle tip and the second nozzle tip are located within the FOV of the second camera image, and the third axis Z direction positions of the first nozzle tip 111 and the second nozzle tip 121 are adjusted by the driving portion for moving the support 150.

[0088] At this time, it is preferable that the third axis Z direction positions of the designated positions P2 be set to positions separated from the substrate S in the third axis Z direction so as to prevent the first nozzle tip 111 and the second nozzle tip 121 from colliding with the substrate S while the first nozzle tip and the second nozzle tip are located within the FOV of the second camera image, and the third axis Z direction positions of the first nozzle tip 111 and the second nozzle tip 121 are adjusted by the driving portion for moving the support 150.

[0089] ​In this embodiment, the first camera 130 can be used to automatically focus the substrate S to obtain the position of the substrate S in the third axis Z direction. Then, the positions of the first nozzle tip 111 and the second nozzle tip 121 in the third axis Z direction are selected so that the first nozzle tip 111 and the second nozzle tip 121 are separated from the substrate S by a predetermined interval.

[0090] Furthermore, although this embodiment uses the first camera 130 to automatically focus the substrate S to detect the position of the substrate S in the third axis direction as an example, it is not limited to this. In order to automatically focus the substrate S, an automatic focusing mechanism based on a laser or a white LED may also be provided.

[0091] like Figure 12 As shown, in the substrate position detection step S150, the position of the substrate S in the third axis Z direction can be accurately detected based on the image of the second camera 140.

[0092] Specifically, since the second camera 140 is configured to observe the work area from the upper side of the work area in a downward tilting direction, the images of the first nozzle tip 111 and the second nozzle tip 121, as well as the mirror images of the first nozzle tip 111 and the second nozzle tip 121 reflected onto the substrate S, are simultaneously seen in the image of the second camera 140.

[0093] Therefore, the further away the first nozzle tip 111 and the second nozzle tip 121 are from the substrate S, the larger the gap between the image and the mirror image of the nozzle tip; the closer the first nozzle tip 111 and the second nozzle tip 121 are to the substrate S, the narrower the gap between the image and the mirror image of the nozzle tip. Therefore, the position of the substrate S in the third axis Z direction can be detected by analyzing the image of the second camera 140 and based on the designated position P2 of the first nozzle tip 111 and the second nozzle tip 121.

[0094] After that, as Figure 13 As shown, in the printing preparation step S160, the drive unit for moving the support 150 can be used to position the first nozzle tip 111 and the second nozzle tip 121 at the printing position on the substrate S. Then, according to the shape of the specified circuit pattern, the positions of the first nozzle tip 111 and the second nozzle tip 121 can be controlled respectively to print the circuit pattern of the required shape on the substrate S.

[0095] The scope of this invention is not limited to the embodiments described above, and various embodiments can be implemented within the scope of the appended claims. Various modifications that can be made by those skilled in the art without departing from the spirit of the invention as claimed also fall within the scope of the claims.

Claims

1. A printing apparatus having a plurality of nozzle heads, comprising: a first nozzle head configured in one side region in a work region on a substrate, provided with a first nozzle tip capable of ejecting ink and a first moving portion capable of moving the first nozzle tip; a second nozzle head configured in another side region in the work region on the substrate, provided with a second nozzle tip capable of ejecting ink and a second moving portion capable of moving the second nozzle tip; a first camera configured on an upper side of the work region for simultaneously observing the first nozzle tip and the second nozzle tip; a second camera configured on an upper side of one side of the work region in a tilted direction toward a lower side for simultaneously observing the first nozzle tip and the second nozzle tip; and a control portion for controlling positions of the first nozzle tip and the second nozzle tip respectively, controlling driving of the first moving portion and the second moving portion based on images obtained from the first camera and the second camera, thereby setting reference positions of the first nozzle tip and the second nozzle tip, and moving the first nozzle tip and the second nozzle tip to specified positions separated from the reference positions by a prescribed distance respectively.

2. The printing apparatus having a plurality of nozzle heads according to claim 1, wherein in order to eject ink by electrohydrodynamic method, the first nozzle head and the second nozzle head each include a high voltage application portion capable of applying voltage to ink.

3. The printing apparatus having a plurality of nozzle heads according to claim 1, wherein the first nozzle head and the second nozzle head are disposed apart in a first axis direction with the work region as a center, and the second camera is disposed apart from the first camera in a second axis direction intersecting the first axis.

4. The printing apparatus having a plurality of nozzle heads according to claim 3, wherein the first nozzle tip and the second nozzle tip are disposed in a tilted manner with respect to the first axis having a tilt.

5. The printing apparatus having a plurality of nozzle heads according to claim 3, wherein the second camera is disposed in a tilted manner with respect to the second axis having a tilt.

6. The printing apparatus having a plurality of nozzle heads according to claim 3, wherein the first moving portion and the second moving portion are configured to be capable of at least three-axis movement.

7. A method of arranging a plurality of nozzle tips, comprising: a first nozzle alignment step of setting a reference position of a first nozzle tip capable of ejecting ink into a work region by an image of a first camera observing the work region on an upper side of the work region and an image of a second camera observing the work region on an upper side of one side of the work region in a tilted direction toward a lower side; a second nozzle alignment step of setting a reference position of a second nozzle tip capable of ejecting ink into the work region by the images of the first camera and the second camera; a substrate position detection step of detecting a position of a substrate based on the image of the second camera; and a printing preparation step of positioning the first nozzle tip and the second nozzle tip at a printing position on the substrate, the method further comprising: ​ ​ After the first nozzle alignment step, a step of moving the first nozzle tip to a specified position that is a prescribed distance away from the reference position is performed, and after the second nozzle alignment step, a step of moving the second nozzle tip to a specified position that is a prescribed distance away from the reference position is performed.

8. The method of arranging a plurality of nozzle tips according to claim 7, wherein The reference position is set by positioning the tip end of the first nozzle tip or the tip end of the second nozzle tip in the center of the field of view of the first camera after positioning the tip end of the first nozzle tip or the tip end of the second nozzle tip in the center of the field of view of the second camera.

9. The method of arranging a plurality of nozzle tips according to claim 7, wherein The specified position is a position in which the first nozzle tip and the second nozzle tip are separated from each other in the horizontal direction with the reference position as the center.

10. The method of arranging a plurality of nozzle tips according to claim 9, wherein The third axis direction position of the specified position is set by separating the position of the substrate detected after the auto-focusing from the substrate by a distance that is specified in advance.

11. The method of arranging a plurality of nozzle tips according to claim 10, wherein In the step of moving to the specified position, the third axis direction positions of the first nozzle tip and the second nozzle tip are adjusted by a drive section for simultaneously moving a printing device that includes the first nozzle tip, the second nozzle tip, the first camera, and the second camera.

12. The method of arranging a plurality of nozzle tips according to claim 11, wherein In the printing preparation step, the third axis direction positions of the first nozzle tip and the second nozzle tip are adjusted by a drive section for simultaneously moving a printing device that includes the first nozzle tip, the second nozzle tip, the first camera, and the second camera.

13. The method of arranging a plurality of nozzle tips according to claim 7, wherein The substrate position detection step detects the height of the substrate using an image of a nozzle tip included in an image obtained by the second camera and a mirror image of the nozzle tip reflected on the substrate.

Images