Inkjet printing apparatus and inkjet printing method using the same

Abstract

The present disclosure relates to an inkjet printing apparatus and an inkjet printing method, the inkjet printing apparatus including: a plurality of nozzles; an inkjet head portion in which the plurality of nozzles are fixed; and a control portion that controls the plurality of nozzles, the control portion including: a full bitmap configuration portion that configures a substrate that is a print target as a full bitmap and stores coordinates of each position; a unit region determination portion that specifies a unit region by analyzing a repetitive pattern on the substrate; a unit region ink droplet fall map creation portion that configures the unit region as a unit bitmap and creates a unit region ink droplet fall map by determining whether or not ink droplets fall for each position on the unit bitmap; a nozzle coordinate analysis portion that analyzes coordinates in a first direction and coordinates in a second direction of each of the plurality of nozzles on the full bitmap; and an ink ejection determination portion that determines whether or not ink is ejected from the plurality of nozzles by corresponding m bits of lower bits of the coordinates in the first direction and n bits of lower bits of the coordinates in the second direction to the unit region ink droplet fall map.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to an inkjet printing apparatus and an inkjet printing method using the same. BACKGROUND

[0002] A display device is a device that displays a screen, and includes a liquid crystal display (LCD), an organic light emitting diode (OLED), and the like. Such a display device is used in various electronic devices such as a cellular phone, a navigator, a digital camera, an electronic book, a portable game machine, or a variety of terminals.

[0003] In a process of manufacturing such a display device, in order to form a layer such as an organic light emitting layer, a quantum dot color filter, or the like, an inkjet printing process can be used. The inkjet printing process forms a predetermined layer by dropping an organic compound on a substrate. The inkjet printing process is simple, can shorten a process time, can increase a material usage efficiency, and can reduce costs due to low manufacturing costs, and thus is useful.

[0004] An inkjet printing apparatus can include an inkjet head portion in which a plurality of nozzles are fixed. Ink is ejected through the plurality of nozzles while the inkjet head portion is moved, and a predetermined pattern can be formed on a substrate. At this time, in order to derive data on whether ink is ejected from the plurality of nozzles at predetermined positions on the substrate, respectively, a large amount of time and a large-capacity memory can be required. SUMMARY

[0005] Embodiments are directed to provide an inkjet printing apparatus and an inkjet printing method using the same, which can shorten a time of deriving information on whether ink is ejected based on positions of nozzles in an inkjet printing process and can reduce a capacity of a memory.

[0006] An inkjet printing apparatus according to an embodiment includes a plurality of nozzles, an inkjet head portion in which the plurality of nozzles are fixed, and a control portion that controls the plurality of nozzles, the control portion including a full bitmap configuration portion that configures a substrate that is a printing target as a full bitmap and stores coordinates of each position, a unit region determination portion that specifies a unit region by analyzing a repetitive pattern on the substrate, a unit region ink drop pattern making portion that configures the unit region as a unit bitmap and decides whether ink drops on each position on the unit bitmap, thereby making a unit region ink drop pattern, a nozzle coordinate analysis portion that analyzes coordinates in a first direction and coordinates in a second direction of each of the plurality of nozzles on the full bitmap, and an ink ejection determination portion that corresponds m bits of a lower bit of the coordinates in the first direction and n bits of a lower bit of the coordinates in the second direction to the unit region ink drop pattern, thereby determining whether ink is ejected from the plurality of nozzles.

[0007] The unit bitmap can include P coordinates in the first direction and Q coordinates in the second direction, the P being 2 m , the Q being 2 n , and the m and the n being natural numbers.

[0008] The m and the n can be the same.

[0009] The m and the n can be 9.

[0010] The unit bitmap can include P x Q unit quadrilaterals, and one side of the unit quadrilaterals can have a length of 1 μm or less.

[0011] The length of the substrate in the first direction can be I times the length of the unit region in the first direction, and the length of the substrate in the second direction can be J times the length of the unit region in the second direction, the substrate can include I x J regions having the same pattern, and the unit region determination section can designate any one of the I x J regions as the unit region.

[0012] The time for analyzing the coordinates of the respective nozzles and determining whether or not to eject ink can be shorter than the time for ejecting ink from the nozzles.

[0013] The coordinates of the respective nozzles at the next time can be analyzed and whether or not to eject ink can be determined during the time for ejecting ink from the nozzles.

[0014] The substrate can include a plurality of first color pixels, a plurality of second color pixels, and a plurality of third color pixels, and the unit region ink drop map creation section can separately create a first unit region ink drop map indicating positions at which to drop first color ink to the first color pixels, a second unit region ink drop map indicating positions at which to drop second color ink to the second color pixels, and a third unit region ink drop map indicating positions at which to drop third color ink to the third color pixels.

[0015] The second direction can be perpendicular to the first direction, the nozzles can be aligned in a direction inclined with respect to the first direction and the second direction, and the advancing direction of the inkjet head section can be inclined with respect to the first direction and the second direction.

[0016] An embodiment relates to an inkjet printing method including: a step of configuring a substrate as a full bitmap and storing coordinates of each position as a printing object; a step of analyzing a repeating pattern on the substrate to specify a unit region; a step of configuring the unit region as a unit bitmap and making a unit region ink droplet falling map by deciding whether or not an ink droplet falls for each position on the unit bitmap; a step of analyzing coordinates in a first direction and coordinates in a second direction of each of a plurality of nozzles on the full bitmap; and a step of corresponding m bits of a lower bit of the coordinates in the first direction and n bits of a lower bit of the coordinates in the second direction to the unit region ink droplet falling map to decide whether or not an ink droplet is ejected from the plurality of nozzles.

[0017] It can be that the unit bitmap includes P coordinates in the first direction and Q coordinates in the second direction, the P is 2 m , the Q is 2 n , and the m and the n are natural numbers.

[0018] It can be that the m and the n are the same.

[0019] It can be that the m and the n are 9.

[0020] It can be that the unit bitmap includes P×Q unit quadrilaterals, and a length of one side of the unit quadrilateral is below 1 μm.

[0021] It can be that a length in the first direction of the substrate is I times a length in the first direction of the unit region, and a length in the second direction of the substrate is J times a length in the second direction of the unit region, the substrate includes I×J regions, the I×J regions have the same pattern, and any one of the I×J regions is specified as the unit region in the step of specifying the unit region.

[0022] It can be that an embodiment relates to an inkjet printing method further including a step of ejecting ink from the plurality of nozzles, and a time of analyzing coordinates of each of the plurality of nozzles and deciding whether or not ink is ejected is shorter than a time of ejecting ink from the plurality of nozzles.

[0023] It can be that, during a period of ejecting ink from the plurality of nozzles, coordinates of each of the plurality of nozzles in a next time are analyzed and whether or not ink is ejected is decided.

[0024] The substrate can include a plurality of first color pixels, a plurality of second color pixels, and a plurality of third color pixels, a first color ink is ejected in correspondence with the first color pixels in an entire area of the substrate, a second color ink is ejected in correspondence with the second color pixels in the entire area of the substrate, and a third color ink is ejected in correspondence with the third color pixels in the entire area of the substrate.

[0025] The second direction can be perpendicular to the first direction, the plurality of nozzles can be aligned in a direction inclined with respect to the first direction and the second direction, the plurality of nozzles can be fixed to an inkjet head, and a traveling direction of the inkjet head can be inclined with respect to the first direction and the second direction.

[0026] (EFFECT OF INVENTION)

[0027] According to the embodiments, it is possible to shorten a time to derive information on whether or not an ink is ejected in association with a position of a nozzle in an inkjet printing process, and to reduce a capacity of a memory. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 FIG. 1 is a view showing an inkjet printing apparatus to which an embodiment is applied.

[0029] Figure 2 FIG. 2 is a block diagram showing a control section of the inkjet printing apparatus to which the embodiment is applied.

[0030] Figure 3 FIG. 3 is a plan view showing a substrate as a print target of the inkjet printing apparatus to which the embodiment is applied.

[0031] Figure 4 FIG. 4 is a plan view showing a unit area of the substrate as the print target of the inkjet printing apparatus to which the embodiment is applied.

[0032] Figure 5 FIG. 5 is a plan view showing the inkjet printing apparatus and the unit area of the substrate to which the embodiment is applied together.

[0033] Figure 6 FIG. 6 is a plan view showing a region in which a first color ink is dropped in the unit area of the substrate.

[0034] Figure 7 FIG. 7 is a first unit area ink drop view showing a position at which the first color ink is dropped.

[0035] Figure 8 FIG. 8 is a plan view showing a region in which a second color ink is dropped in the unit area of the substrate.

[0036] Figure 9is a second unit area ink drop chart showing a position at which the second color ink is dropped.

[0037] Figure 10 is a plan view showing a region in which the third color ink is dropped in the unit area of the substrate.

[0038] Figure 11 is a third unit area ink drop chart showing a position at which the third color ink is dropped.

[0039] Figure 12 is a plan view showing a unit area of a substrate as a print target of an inkjet printing apparatus to which an embodiment is applied.

[0040] Figure 13 is a sequence chart showing an inkjet printing method to which an embodiment is applied.

[0041] Symbol explanation:

[0042] 110: substrate; 200: inkjet head; 210: nozzle; 300: control section; 310: preprocessing section; 312: full bitmap configuration section; 314: unit area decision section; 316: unit area ink drop chart creation section; 320: nozzle coordinate analysis section; 330: ink ejection decision section; UR: unit area; UQ: unit quadrangle. DETAILED DESCRIPTION

[0043] Hereinafter, each embodiment of the present application will be explained in detail with reference to the attached drawings, so that those skilled in the art can easily carry it out. The present application can be realized in various different modes, and is not limited to each embodiment explained herein.

[0044] In order to clearly explain the present application, parts irrelevant to the explanation are omitted, and the same or similar constituent elements are given the same symbols throughout the specification.

[0045] Further, the size and thickness of each constituent illustrated are arbitrarily shown for the convenience of explanation, and the present application is not necessarily limited to the illustrated cases. In the drawings, the thickness is exaggeratedly shown in order to clearly show each layer and region. Further, in the drawings, the thickness of part of the layers and regions is exaggeratedly shown for the convenience of explanation.

[0046] Further, when a part is positioned on or above another part, it includes not only a case where it is directly positioned on the other part, but also a case where another part is interposed therebetween. Conversely, when a part is directly positioned on another part, it means that no other part is interposed therebetween. Further, positioned on or above a part serving as a reference means positioned above or below the part serving as a reference, and does not necessarily mean positioned on or above the side in the direction of gravity.

[0047] Further, in the entire specification, when a certain part includes a certain constituent element, unless particularly noted otherwise, it does not exclude the inclusion of other constituent elements, but means that other constituent elements can also be included.

[0048] Further, in the entire specification, "on a plane" means a case where the object part is observed from above, and "on a cross section" means a case where a cross section of the object part is observed from a side.

[0049] Hereinafter, referring to Figures 1 to 11 An embodiment relates to an inkjet printing device.

[0050] Figure 1 is a view showing an inkjet printing device according to an embodiment, Figure 2 is a block diagram showing a control section of an inkjet printing device according to an embodiment. Figure 3 is a plan view showing a substrate as a printing target of an inkjet printing device according to an embodiment, Figure 4 is a plan view showing a unit area of a substrate as a printing target of an inkjet printing device according to an embodiment, Figure 5 is a plan view showing an inkjet printing device according to an embodiment and a unit area of a substrate. Figure 6 is a plan view showing an area where a first color ink is dropped in a unit area of a substrate, Figure 7 is a first unit area ink drop map showing a position where a first color ink is dropped. Figure 8 is a plan view showing an area where a second color ink is dropped in a unit area of a substrate, Figure 9 is a second unit area ink drop map showing a position where a second color ink is dropped. Figure 10 is a plan view showing an area where a third color ink is dropped in a unit area of a substrate, Figure 11 is a third unit area ink drop map showing a position where a third color ink is dropped.

[0051] As Figure 1 An embodiment relates to an inkjet printing device including a plurality of nozzles 210 and an inkjet head section 200 in which the plurality of nozzles 210 are fixed.

[0052] A plurality of nozzles 210 can be arranged with a certain interval. The plurality of nozzles 210 can be arranged in one row. However, it is not limited thereto, and the plurality of nozzles 210 can be arranged in two or more rows. The plurality of nozzles 210 can each include a hole capable of ejecting ink in one direction, for example, the hole can be located in a direction perpendicular to the substrate 110 as a printing target. However, this is only an example, and the direction of ink ejection of the plurality of nozzles 210 can be different. In addition, the direction of ink ejection of the plurality of nozzles 210 can not be a direction perpendicular to the substrate 110, but can be a direction inclined with respect to the substrate 110. The plurality of nozzles 210 can include a circular hole, but this is only an example, and the shape of the ink ejection port of the plurality of nozzles 210 can be variously changed. The number and size of the plurality of nozzles 210 included in the inkjet printing apparatus according to an embodiment can be variously changed, and the printing resolution can be different depending on the number and size of the nozzles 210.

[0053] The inkjet head 200 can have a bar shape extending long in one direction. The plurality of nozzles 210 can be fixed to one side surface of the inkjet head 200. The substrate 110 as a printing target can be configured in a polygonal shape. For example, the planar shape of the substrate 110 can be configured in a quadrangle including two sides parallel to the first direction D1 and two sides parallel to the second direction D2. The second direction D2 can be a direction perpendicular to the first direction D1. At this time, the inkjet head 200 can be arranged to extend long in a direction inclined with respect to the first direction D1 and the second direction D2. The inkjet head 200 can be moved in a direction perpendicular to the direction in which the inkjet head 200 extends. That is, the inkjet head 200 can be moved in a direction inclined with respect to the first direction D1 and the second direction D2. However, this is only an example, and the inkjet head 200 can be arranged to extend long in a direction parallel to the first direction D1 and can be moved in the second direction D2. Alternatively, the inkjet head 200 can be arranged to extend long in a direction parallel to the second direction D2 and can be moved in the first direction D1. In the case where the inkjet head 200 is arranged to extend long in a direction parallel to the first direction D1 or the second direction D2, the nozzles 210 used among the plurality of nozzles 210 and the nozzles 210 not used can be divided. That is, a part of the nozzles 210 can be continuously used, and the other part of the nozzles 210 can not be continuously used, and thus it is limited in maximizing the use rate of the nozzles 210. Therefore, by arranging the inkjet head 200 of the inkjet printing apparatus according to an embodiment in a direction inclined with respect to the side of the substrate 110 and moving it, the use efficiency of the nozzles 210 can be improved.

[0054] Compared to the case where the inkjet head 200 is arranged side by side with the edge of the substrate 110 and is moved, in the case where the inkjet head 200 is arranged obliquely with respect to the edge of the substrate 110 and is moved, the algorithm for determining whether or not the ink is ejected from the plurality of nozzles 210 can become more complicated. As shown in FIG. 7, one embodiment relates to an inkjet printing apparatus that further includes a control section 300 that controls the plurality of nozzles 210. The control section 300 simplifies the algorithm for determining whether or not the ink is ejected from the plurality of nozzles 210, so that the time for deriving information on whether or not the ink is ejected can be shortened, and the capacity of the memory can be reduced. Figure 2

[0055] One embodiment relates to an inkjet printing apparatus whose control section 300 can include a preprocessing section 310 that analyzes a pattern on the substrate 110 that is a print target, a nozzle coordinate analysis section 320 that analyzes the positions of the plurality of nozzles 210, and an ink ejection determination section 330 that determines whether or not the ink is ejected from the plurality of nozzles 210.

[0056] The preprocessing section 310 can include a full-bit map construction section 312 that constructs the substrate 110 as a full-bit map and stores the coordinates of each position, a unit region determination section 314 that analyzes a repeating pattern on the substrate 110 to specify a unit region, and a unit region ink drop map creation section 316 that constructs the unit region as a unit-bit map and determines whether or not the ink drops on each position on the unit-bit map, thereby creating a unit region ink drop map.

[0057] ​The full-bitmap configuration unit 312 can divide the substrate 110 into a grid shape along the first direction D1 and the second direction D2. That is, the substrate 110 can be divided into quadrilateral-shaped regions including two sides parallel to the first direction D1 and two sides parallel to the second direction D2. At this time, the position of each region can be represented as inherent coordinates related to the order in the first direction D1 and the second direction D2. The first direction D1 can be a row direction, and the second direction D2 can be a column direction. Each coordinate can be represented as a binary number. For example, the coordinates of the region located in the first row and first column can be represented as (0, 0), the coordinates of the region located in the first row and second column can be represented as (0, 01), the coordinates of the region located in the first row and third column can be represented as (0, 10), and the coordinates of the region located in the first row and fourth column can be represented as (0, 11). The coordinates of the region located in the 2nd row and 1st column can be represented as (01, 0), the coordinates of the region located in the 2nd row and 2nd column can be represented as (01, 01), the coordinates of the region located in the 2nd row and 3rd column can be represented as (01, 10), and the coordinates of the region located in the 2nd row and 4th column can be represented as (01, 11). The coordinates of the region located in the 4th row and 4th column can be represented as (11, 11), and the coordinates of the region located in the 512th row and 512th column can be represented as (111111111, 111111111). The full bitmap configuration unit 312 can store coordinates related to the position on the plane of the substrate 110.

[0058] The substrate 110, which is to be printed, can be a substrate for a display device and can include multiple pixels as the basic unit for image display. In this case, the multiple pixels can be configured to have a repeating pattern. The unit area determination unit 314 can analyze the repeating pattern on the substrate 110 and thereby designate a unit area UR. Figure 3 As shown, the substrate 110 can be divided into I regions of equal width along a first direction D1, and into J regions of equal width along a second direction D2. Therefore, the substrate 110 can include I×J regions of equal size along the first direction D1 and the second direction D2. The I×J regions can have the same pattern, and one of the I×J regions can be designated as a unit region UR.

[0059] The length of the substrate 110 in the first direction D1 may be approximately I times the length of the unit area UR in the first direction D1. The length of the substrate 110 in the second direction D2 may be approximately J times the length of the unit area UR in the second direction D2. The substrate 110 may include a display area for displaying a screen and a peripheral area located around the display area. In the above description, the length of the substrate 110 in the first direction D1 represents the length of the display area in the first direction D1, and the length of the substrate 110 in the second direction D2 represents the length of the display area in the second direction D2.

[0060] The unit region ink droplet deposition map creation section 316 can first configure the unit region UR as a unit bitmap. As shown in Figure 4 The unit region ink droplet deposition map creation section 316 can divide the unit region UR into a lattice shape along the first direction D1 and the second direction D2. The unit region UR can be divided into P regions having the same width along the first direction D1, and can be divided into Q regions having the same width along the second direction D2. Thus, the unit region UR can include P x Q regions having the same size along the first direction D1 and the second direction D2. Each of the P x Q regions is referred to as a unit quadrangle UQ. The unit quadrangle UQ can have a shape including two sides in parallel with the first direction D1 and two sides in parallel with the second direction D2. The size of the unit quadrangle UQ constituting the unit region UR can be substantially the same as the size of the region represented by the coordinates of the full bitmap.

[0061] The length of one side of the unit quadrangle UQ can be about 1 μm or less. However, it is not limited thereto, and the resolution of the unit region ink droplet deposition map can be changed according to the length of one side of the unit quadrangle UQ. The unit quadrangle UQ can be configured as a rectangle or a square. The length in the first direction D1 of the unit region UR can be about P times the length in the first direction D1 of the unit quadrangle UQ. The length in the second direction D2 of the unit region UR can be about Q times the length in the second direction D2 of the unit quadrangle UQ. At this time, as shown in Mathematical Expression 1 and Mathematical Expression 2, P and Q can be a square number of 2. P can be 2 raised to the power of m, and Q can be 2 raised to the power of n.

[0062]

Mathematical Expression 1

[0063] P = 2 m (m is a natural number)

[0064]

Mathematical Expression 2

[0065] Q = 2 n (n is a natural number)

[0066] At this time, m and n can be the same, and thus P and Q can also be the same. For example, P and Q can be 16, which is 2 raised to the power of 4. That is, the unit region UR can include 16 x 16 (= 256) unit quadrangles UQ.

[0067] Multiple pixels may be located within a unit area UR. These multiple pixels may include a first-color pixel R, a second-color pixel G, and a third-color pixel B. The first-color pixel R may display red, the second-color pixel G may display green, and the third-color pixel B may display blue. However, this is merely an example; the multiple pixels may also include pixels displaying colors other than red, green, and blue. For example, the multiple pixels may also include white pixels. Alternatively, the multiple pixels may also include pixels displaying cyan, pixels displaying magenta, and pixels displaying yellow.

[0068] For example, two first-color pixels R, four second-color pixels G, and two third-color pixels B can be located within a unit region UR. Within the unit region UR, the second-color pixels G can be arranged at predetermined intervals along a first direction D1 and a second direction D2. Furthermore, the first-color pixels R and the third-color pixels B can be arranged at predetermined intervals along the first direction D1 and the second direction D2. The first-color pixels R and the second-color pixels G can be configured to be adjacent in a direction inclined relative to the first direction D1 and the second direction D2. The second-color pixels G and the third-color pixels B can be configured to be adjacent in a direction inclined relative to the first direction D1 and the second direction D2. The configuration of the multiple pixels is not limited to this and various variations are possible. The substrate 110 can include I×J regions, and within the I×J regions, the configuration of the multiple pixels can be identical.

[0069] like Figure 5 As shown, the inkjet head 200 can be located on a unit area UR, and a plurality of nozzles 210 can be arranged in a direction inclined relative to the first direction D1 and the second direction D2. A portion of the plurality of nozzles 210 can overlap with any of the plurality of pixels. Another portion of the plurality of nozzles 210 can not overlap with the plurality of pixels. In this case, whether or not each nozzle 210 ejects ink can be determined based on whether or not each nozzle 210 overlaps with the plurality of pixels. When the first color ink is dripped, the nozzle 210 can eject ink in the portion overlapping with the first color pixel R, and not eject ink in the remaining portion. When the second color ink is dripped, the nozzle 210 can eject ink in the portion overlapping with the second color pixel G, and not eject ink in the remaining portion. When the third color ink is dripped, the nozzle 210 can eject ink in the portion overlapping with the third color pixel B, and not eject ink in the remaining portion. Therefore, the unit area ink droplet image production unit 316 can separately produce a first unit area ink droplet image indicating the position where the first color ink drops onto the first color pixel R, a second unit area ink droplet image indicating the position where the second color ink drops onto the second color pixel G, and a third unit area ink droplet image indicating the position where the third color ink drops onto the third color pixel B.

[0070] likeFigure 6 As shown, when the first color ink is dripped, the nozzle 210 corresponding to the positions of the 3rd row and 4th column, the 4th row and 3rd to the 4th row and 5th column, the 5th row and 2nd to the 5th row and 6th column, the 6th row and 2nd to the 6th row and 6th column, the 7th row and 3rd to the 7th row and 5th column, the 8th row and 4th column, the 10th row and 11th column, the 11th row and 10th to the 11th row and 12th column, the 12th row and 9th to the 12th row and 13th column, the 13th row and 9th to the 13th row and 13th column, the 14th row and 10th to the 14th row and 12th column, and the 15th row and 11th column within the unit area UR can be set to spray the first color ink.

[0071] like Figure 7 As shown, the ink droplet pattern of the first unit area represents whether the first color ink has been ejected, related to the coordinates within the unit area UR. The coordinates can be represented as binary numbers. For example, if the input is (10, 11) corresponding to the binary coordinates in row 3, column 4, then 1 is output as the signal for ink ejection. Furthermore, if the input is (11, 10), (11, 11), or (11, 100) corresponding to the binary coordinates in rows 4, columns 3 through 4, columns 5, then 1 is output as the signal for ink ejection. Additionally, if the input is (100, 01), (100, 10), (100, 11), (100, 100), or (100, 101) corresponding to the binary coordinates in rows 5, columns 2 through 5, columns 6, then 1 is output as the signal for ink ejection. Similarly, if the input is the binary coordinates corresponding to the columns 2 to 6, 3 to 5, 4, 10, 11, 10 to 12, 9 to 13, 9 to 13, 10 to 13, 10 to 12, and 111, the output will be 1, which will be used as the signal to eject ink. Furthermore, if the input is a binary coordinate corresponding to any position other than the following: row 3, column 4; row 4, column 3 to row 4, column 5; row 5, column 2 to row 5, column 6; row 6, column 2 to row 6, column 6; row 7, column 3 to row 7, column 5; row 8, column 4; row 10, column 11; row 11, column 10 to row 11, column 12; row 12, column 9 to row 12, column 13; row 13, column 9 to row 13, column 13; row 14, column 10 to row 14, column 12; and row 15, column 11, then it will be used as a signal not to eject ink, and the output will be 0.

[0072] like Figure 8As shown, when the second color ink is dripped, the nozzle 210 corresponding to the positions of the 1st row 8th column and 1st row 14th column, the 2nd row 7th to 2nd row 9th column, the 2nd row 13th to 2nd row 15th column, the 3rd row 6th to 3rd row 8th column, the 3rd row 14th to 3rd row 16th column, the 4th row 7th column and 4th row 15th column, the 8th row 7th column and 8th row 15th column, the 9th row 6th to 9th row 8th column, the 9th row 14th to 9th row 16th column, the 10th row 7th to 10th row 9th column, the 10th row 13th to 10th row 15th column, and the 11th row 8th column and 11th row 14th column within the unit area UR can be set to spray the second color ink.

[0073] like Figure 9 As shown, the second unit area ink droplet diagram indicates whether the second color ink is ejected, related to the coordinates within the unit area UR. For example, if the input is the binary coordinates (0, 111) and (0, 1110) corresponding to the first row, eighth column and the first row, fourth column, respectively, then the output is 1 as a signal for ink ejection. Furthermore, if the input is the binary coordinates (1, 110), (1, 111), and (1, 1000) corresponding to the second row, seventh column to the second row, ninth column, then the output is 1 as a signal for ink ejection. Additionally, if the input is the binary coordinates (1, 1100), (1, 1101), and (1, 1110) corresponding to the second row, thirteenth column to the second row, fifteenth column, then the output is 1 as a signal for ink ejection. Similarly, if the input is the binary coordinates corresponding to the columns 6 to 8 of row 3, 14 to 16 of row 3, 7 and 15 of row 4, 7 and 15 of row 8, 6 to 8 of row 9, 14 to 16 of row 9, 7 to 9 of row 10, 13 to 15 of row 10, and 8 and 14 of row 11, then it will serve as the signal for ejecting ink and will output 1. Furthermore, if the input is a binary coordinate corresponding to any position other than the following: row 1, column 8 and column 14; row 2, columns 7 to 9; row 2, columns 13 to 15; row 3, columns 6 to 8; row 3, columns 14 to 16; row 4, columns 7 and 15; row 8, columns 7 and 15; row 8, columns 7 to 8; row 9, columns 14 to 16; row 10, columns 7 to 9; row 10, columns 13 to 15; and row 11, columns 8 and 14, the input will be considered a signal not to eject ink and will output 0.

[0074] like Figure 10As shown, when the third color ink is dripped, the nozzle 210 corresponding to the positions of the 3rd row 11th column, the 4th row 10th to the 4th row 12th column, the 5th row 9th to the 5th row 13th column, the 6th row 8th to the 6th row 14th column, the 7th row 9th to the 7th row 13th column, the 8th row 10th to the 8th row 12th column, the 9th row 11th column, the 10th row 4th column, the 11th row 3rd to the 11th row 5th column, the 12th row 2nd to the 12th row 6th column, the 13th row 1st to the 13th row 7th column, the 14th row 2nd to the 14th row 6th column, the 15th row 3rd to the 15th row 5th column, and the 16th row 4th column within the unit area UR can be set to spray the third color ink.

[0075] like Figure 11 As shown, the ink droplet diagram of the third unit region indicates whether the third color ink has been ejected, related to the coordinates within the unit region UR. For example, if the input is the binary coordinate (10, 1010) corresponding to the 3rd row, 11th column, it will output 1 as a signal for ink ejection. Furthermore, if the input is the binary coordinate (11, 1001), (11, 1010), or (11, 1011) corresponding to the 4th row, 10th to 4th row, 12th columns, it will output 1 as a signal for ink ejection. Additionally, if the input is the binary coordinate (100, 1000), (100, 1001), (100, 1010), (100, 1011), or (100, 1100) corresponding to the 5th row, 9th to 5th row, 13th columns, it will output 1 as a signal for ink ejection. Similarly, if the input is the binary coordinates corresponding to the columns 6-6-14, 7-7-13, 8-8-12, 9-11, 10-4, 11-15, 12-16, 13-13, 14-14, 15-15, and 16-14, then it will serve as the signal for ejecting ink and output 1. Furthermore, if the input is a binary coordinate corresponding to a position other than the following: row 3, column 11; row 4, columns 10 to 12; row 5, columns 9 to 13; row 6, columns 8 to 14; row 7, columns 9 to 13; row 8, columns 10 to 12; row 9, column 11; row 10, column 4; row 11, columns 3 to 5; row 12, columns 2 to 6; row 13, columns 1 to 7; row 14, columns 2 to 6; row 15, columns 3 to 5; and row 16, column 4, then it will be used as a signal not to eject ink, and the output will be 0.

[0076] As described above, the preprocessing unit 310 can store coordinates corresponding to the entire area of ​​the substrate 110 and specify a unit area UR, thereby creating a unit area ink droplet map related to each ink color.

[0077] The nozzle coordinate analysis unit 320 can analyze the positions of each of the plurality of nozzles 210 fixed to the inkjet head 200. The inkjet head 200 can correspond to a predetermined position on the substrate 110, and the plurality of nozzles 210 can each correspond to predetermined coordinates on a full-bitmap of the substrate 110. The nozzle coordinate analysis unit 320 can receive information on the coordinates of each position on the substrate 110 from the full-bitmap configuration unit 312 of the preprocessing unit 310, and can find the coordinates corresponding to each nozzle 210. At this time, the nozzle coordinate analysis unit 320 can analyze the coordinates of each of the plurality of nozzles 210 in the first direction D1 and the second direction D2. At this time, the coordinates can be represented as binary numbers. For example, when the nozzle 210 is located at the position corresponding to the 1000th row and 1000th column of the substrate 110, the coordinates of the nozzle 210 can be output as (1111100111, 1111100111).

[0078] The ink ejection determination unit 330 can receive the unit area ink droplet map transmitted from the unit area ink droplet map creation unit 316 of the preprocessing unit 310, and can receive the coordinates of the nozzle 210 transmitted from the nozzle coordinate analysis unit 320. The ink ejection determination unit 330 can determine whether or not ink is ejected from the corresponding nozzle 210 based on the received information. Storing information on whether or not ink is ejected corresponding to coordinates in the first direction D1 and the second direction D2 on the full bitmap may increase the computation time and memory capacity. One embodiment of the inkjet printing apparatus can store only the information on whether or not ink is ejected corresponding to coordinates in the first direction D1 and the second direction D2 on the unit bitmap, and determine whether or not ink is ejected from the corresponding nozzle 210 using only a portion of the lower bits of the coordinates corresponding to the position of the nozzle 210. The unit bitmap may include P coordinates in the first direction D1 and Q coordinates in the second direction D2, where P can be 2 to the power of m and Q can be 2 to the power of n. In this case, the ink ejection determination unit 330 can map the lower m-bits of the coordinates in the first direction D1 and the lower n-bits of the coordinates in the second direction D2 of each of the multiple nozzles 210 to the unit area ink droplet map, thereby determining whether or not ink is ejected from each of the multiple nozzles 210. Therefore, the inkjet printing apparatus according to one embodiment can significantly reduce the computation time and memory capacity required to determine whether or not ink is ejected.

[0079] For example, in a case where a first color ink is caused to drop, when the position of the nozzle 210 corresponds to the coordinates (10, 11), 1 can be output as a signal to eject ink. The substrate 110 can include a plurality of regions, and each of the plurality of regions can have the same pattern as the unit region UR. Therefore, in a case where the unit region UR includes 16 x 16 (= 256) unit quadrilaterals UQ, whether or not ink is ejected in the coordinates (0, 0) can be the same as whether or not ink is ejected in the coordinates (10000, 0), (1, 10000), (10000, 10000), and the like. Likewise, whether or not ink is ejected in the coordinates (10, 11) can be the same as whether or not ink is ejected in the coordinates (10010, 11), (10, 10011), (10010, 10011), (110010, 110011), and the like. Therefore, in a case where the position of the nozzle 210 corresponds to the coordinates (10010, 11), (10, 10011), (10010, 10011), (110010, 110011), and the like, 1 can be output as a signal to eject ink.

[0080] For example, the coordinates in the first direction D1 and the coordinates in the second direction D2 on the full bitmap can each be constituted by 32 bits. At this time, since whether or not ink is ejected from the nozzle 210 can be determined using the lower 4 bits of the coordinates in the first direction D1 and the lower 4 bits of the coordinates in the second direction D2, the operation time and the capacity of the memory for determining whether or not ink is ejected can be greatly reduced.

[0081] In the above, a case where m and n are 4 is described, but the present embodiment is not limited thereto, and the values of m and n can be variously changed. m and n can also have different values. m and n are natural numbers. Hereinafter, a case where m and n are 4 will be described with reference to the drawings. Figure 12 A modification example of the values of m and n will be described.

[0082] Figure 12 is a plan view showing a unit region of a substrate as a print target of an inkjet printing apparatus according to an embodiment.

[0083] As shown in Figure 12 , the unit region UR can be divided into a lattice shape along the first direction D1 and the second direction D2. The unit region UR can be divided into 2 9 (= 512) regions having the same width along the first direction D1, and can be divided into 2 9(=512) regions. That is, m and n can be 9, respectively. At this time, the unit region UR can include 512x512 (=262144) regions having the same size along the first direction D1 and the second direction D2. Each of the 512x512 (=262144) regions can be referred to as a unit quadrangle UQ. The unit quadrangle UQ can have a shape including two edges in parallel with the first direction D1 and two edges in parallel with the second direction D2.

[0084] A length of one edge of the unit quadrangle UQ can be about 1 μm or less. However, it is not limited thereto, and the resolution of the unit region ink drop map can be changed according to the length of one edge of the unit quadrangle UQ. The unit quadrangle UQ can be configured as a rectangle or a square. A length in the first direction D1 of the unit region UR can be about 512 times a length in the first direction D1 of the unit quadrangle UQ. A length in the second direction D2 of the unit region UR can be about 512 times a length in the second direction D2 of the unit quadrangle UQ. For example, a length of each edge of the unit region UR can be about 372 μm. At this time, a length of each edge of the unit quadrangle UQ can be about 0.73 μm (=372 / 512). That is, the length of one edge of the unit quadrangle UQ can become about 1 μm or less. The values of m and n can be appropriately selected in consideration of the size and resolution of the unit region UR, etc.

[0085] The ink ejection determination unit 330 can correspond the lower 9 bits of the coordinates in the first direction D1 and the lower 9 bits of the coordinates in the second direction D2 of each of the plurality of nozzles 210 to the unit region ink drop map, and determine whether or not to eject ink from each of the plurality of nozzles 210.

[0086] In the case where the unit region UR includes 512x512 (=262144) unit quadrangles UQ, whether or not to eject ink at the coordinates (0, 0) can be the same as whether or not to eject ink at the coordinates (1000000000, 0), (0, 1000000000), (1000000000, 1000000000), (11000000000, 11000000000), (101000000000, 101000000000), etc. Therefore, on the full-bit map, as an output value of whether or not to eject ink at the coordinates (1000000000, 0), (0, 1000000000), (1000000000, 1000000000), (11000000000, 11000000000), (101000000000, 101000000000), etc., a signal of whether or not to eject ink at the coordinates (0, 0) in the unit region UR can be output.

[0087] As described above, the ink ejection determination section 330 can determine whether or not the ink is ejected from the plurality of nozzles 210. The plurality of nozzles 210 can respectively receive the transmission of the output value for the determination of whether or not the ink is ejected from the ink ejection determination section 330, and according to the output value, a part of the plurality of nozzles 210 can eject the ink, and the other part of the plurality of nozzles 210 can not eject the ink. If the ejection of the ink from the plurality of nozzles 210 fixed to the inkjet head 200 is completed, the inkjet head 200 can be moved. The inkjet head 200 stops after moving a predetermined distance, and the nozzle coordinate analysis section 320 analyzes the positions of the plurality of nozzles 210 in the stopped place again. Further, the ink ejection determination section 330 determines whether or not the ink is ejected from the plurality of nozzles 210 in the stopped place again. According to the output value for the determination of whether or not the ink is ejected again, a part of the plurality of nozzles 210 ejects the ink.

[0088] The time for analyzing the coordinates of the plurality of nozzles 210 each and determining whether or not the ink is ejected at a place where the inkjet head 200 stops can be shorter than the time for ejecting the ink from the plurality of nozzles 210 at the place. At this time, the coordinates of the plurality of nozzles 210 each at a place where the inkjet head 200 will be located at a next time can be analyzed and whether or not the ink is ejected can be determined during the period for ejecting the ink from the plurality of nozzles 210 at a time. That is, the process for ejecting the ink and the operation for deriving whether or not the ink is ejected at the next time can be performed at the same time. Therefore, the time for performing the inkjet printing process can be greatly shortened.

[0089] Hereinafter, an embodiment related to an inkjet printing method will be described with reference to Figure 13 .

[0090] Figure 13 is a sequence diagram illustrating an inkjet printing method according to an embodiment.

[0091] As illustrated in Figure 13 , the inkjet printing method according to an embodiment can include a step of configuring a substrate as a full bitmap as a printing target and storing coordinates of each position (S1100). The substrate can be divided into a lattice shape along a first direction and a second direction perpendicular to the first direction, and the positions of the divided regions can be expressed by coordinates. The coordinates can be expressed as binary numbers.

[0092] Then, a unit region can be designated by analyzing a repetitive pattern on the substrate (S1200). The substrate can be a substrate for a display device, and can include a plurality of pixels as a basic unit of a screen display. At this time, the plurality of pixels can be configured to have a repetitive pattern. The substrate can be divided into a plurality of regions having the same pattern using the repetitive pattern of the plurality of pixels. The substrate can include I×J regions having the same size along the first direction and the second direction. The I×J regions can have the same pattern, and one of the I×J regions can be designated as a unit region.

[0093] Then, the unit region can be configured as a unit bitmap, and whether or not ink drops are to be dropped at each position on the unit bitmap can be determined, thereby making a unit region ink drop map (S1300). The unit region can be divided into a lattice shape along the first direction and the second direction. The unit region can include P x Q regions having the same size along the first direction and the second direction. Each of the P x Q regions is referred to as a unit quadrangle. The size of the unit quadrangle configuring the unit region can be substantially the same as the size of the region indicated by the coordinates of the full bitmap. The length of one side of the unit quadrangle can be less than or equal to about 1 μm, but is not limited thereto. P and Q can be a square number of 2. P can be 2 raised to the power of m, and Q can be 2 raised to the power of n. m and n can be natural numbers, and can be the same or different. For example, m and n can be 9. At this time, the unit region can be configured by 512 x 512 (= 262144) unit quadrangles having the same size.

[0094] The plurality of pixels can be located within the unit region. The plurality of pixels can include first color pixels, second color pixels, and third color pixels. When the plurality of nozzles are located on the unit region, a portion of the nozzles can overlap the pixels, and another portion of the nozzles can not overlap the pixels. The portion overlapping the pixels can be determined as a portion to eject ink, and the portion not overlapping the pixels can be determined as a portion not to eject ink. According to this determination, the unit region ink drop map can be made. The unit region ink drop map can be made for each pixel, respectively. That is, a first unit region ink drop map indicating positions at which first color ink is to be dropped to the first color pixels, a second unit region ink drop map indicating positions at which second color ink is to be dropped to the second color pixels, and a third unit region ink drop map indicating positions at which third color ink is to be dropped to the third color pixels can be made, respectively and individually.

[0095] Then, the coordinates in the first direction and the coordinates in the second direction of the plurality of nozzles on the full bitmap can be analyzed (S1400). When the inkjet head portion corresponds to a predetermined position on the substrate, the plurality of nozzles can correspond to predetermined coordinates on the full bitmap of the substrate. At this time, the coordinates in the first direction and the coordinates in the second direction of the plurality of nozzles can be expressed as binary numbers.

[0096] Then, the lower m bits of the coordinates in the first direction and the lower n bits of the coordinates in the second direction are corresponded to the unit area ink drop pattern, so that the ink ejection of the plurality of nozzles is determined (S1500). At this time, the first color ink can be ejected from the plurality of nozzles corresponding to the first color pixels in the entire area of the substrate using the first unit area ink drop pattern. Next, the second color ink can be ejected from the plurality of nozzles corresponding to the second color pixels in the entire area of the substrate using the second unit area ink drop pattern. Next, the third color ink can be ejected from the plurality of nozzles corresponding to the third color pixels in the entire area of the substrate using the third unit area ink drop pattern.

[0097] The time for analyzing the coordinates of the plurality of nozzles each and determining the ink ejection at a point where the inkjet head is stopped can be shorter than the time for ejecting the ink from the plurality of nozzles at the point. At this time, the coordinates of the plurality of nozzles each at a point where the inkjet head is to be located at a next time can be analyzed and the ink ejection is determined in a time period in which the ink is ejected from the plurality of nozzles. That is, the process of ejecting the ink and the operation of deriving the ink ejection at the next time can be performed simultaneously. Therefore, the time for performing the inkjet printing process can be greatly shortened.

[0098] The step S1100 of configuring the substrate as a full bitmap and storing the address of each position, the step S1200 of storing the unit area, and the step S1300 of making the unit area ink drop pattern are pre-processing steps, which can be implemented before the ink drop process is started.

[0099] The step S1400 of analyzing the coordinates of the plurality of nozzles each and the step S1500 of determining the ink ejection of the plurality of nozzles can be repeatedly performed from the initial position of the inkjet head to the end point along the moving direction. The step S1400 of analyzing the coordinates of the plurality of nozzles each and the step S1500 of determining the ink ejection of the plurality of nozzles can be performed together while the ink drop process is performed.

[0100] The above-described embodiments of the present application have been described in detail, but the scope of the present application is not limited to the above-described embodiments, and various modifications and improvements of the present application defined in the claims are also included in the scope of the present application.

Claims

1. An inkjet printing apparatus, comprising: Multiple nozzles; The inkjet head is fixed with the aforementioned multiple nozzles; as well as The control unit controls the plurality of nozzles. The control unit includes: The full bitmap construction unit constructs a full bitmap of the substrate to be printed and stores the coordinates of each position; The unit area determination unit analyzes the repeating pattern on the substrate to designate a unit area; The unit area ink droplet map production unit constructs the unit area into a unit bitmap, and determines whether ink drops fall on the unit bitmap at each position, thereby producing a unit area ink droplet map. The nozzle coordinate analysis unit analyzes the coordinates of each of the plurality of nozzles in a first direction and in a second direction on the full-bit map, wherein the coordinates in the first direction and the coordinates in the second direction are represented as binary numbers; and The ink ejection determination unit maps the lower m bits of the binary number of the coordinates in the first direction (starting from the rightmost position) and the lower n bits of the binary number of the coordinates in the second direction (starting from the rightmost position) to the ink droplet map of the unit area, thereby determining whether or not ink is ejected from the multiple nozzles.

2. The inkjet printing apparatus according to claim 1, wherein, The unit bitmap includes P coordinates in the first direction and Q coordinates in the second direction. The P is 2 m , The Q is 2 n , The m and n are natural numbers.

3. The inkjet printing apparatus according to claim 2, wherein, The m and the n are the same.

4. The inkjet printing apparatus according to claim 3, wherein, The value of m and the value of n are 9.

5. The inkjet printing apparatus according to claim 2, wherein, The unit bitmap comprises P×Q unit quadrilaterals. The length of one side of the unit quadrilateral is less than 1 μm.

6. The inkjet printing apparatus according to claim 2, wherein, The length of the substrate in the first direction is I times the length of the unit region in the first direction. The length of the substrate in the second direction is J times the length of the unit region in the second direction. The substrate comprises I×J regions. The I×J regions have the same pattern. The unit region determination unit designates any one of the I×J regions as the unit region.

7. The inkjet printing apparatus according to claim 2, wherein, The time to analyze the coordinates of each of the multiple nozzles and determine whether or not ink is ejected is shorter than the time it takes for the multiple nozzles to eject ink.

8. The inkjet printing apparatus according to claim 7, wherein, During the period when the multiple nozzles are ejecting ink, the coordinates of each of the multiple nozzles in the next time step are analyzed and a decision is made on whether or not ink is ejected.

9. The inkjet printing apparatus according to claim 2, wherein, The substrate includes a plurality of first color pixels, a plurality of second color pixels, and a plurality of third color pixels. The ink droplet map of each unit area is created separately: A droplet map of the first unit area representing the location where the first color ink is dropped onto the first color pixel; A second unit area ink drop map representing the location where the second color ink is dropped onto the second color pixel; and The third unit area is a droplet map showing the location where the third color ink is dropped onto the third color pixel.

10. The inkjet printing apparatus according to claim 2, wherein, The second direction is perpendicular to the first direction. The plurality of nozzles are aligned in a direction inclined relative to the first direction and the second direction. The direction of travel of the inkjet head is inclined relative to the first direction and the second direction.

11. An inkjet printing method, comprising: The steps of constructing a full bitmap of the substrate to be printed and storing the coordinates of each position; The step of analyzing repeating patterns on the substrate to specify unit areas; The steps are as follows: to construct the unit region into a unit bitmap, and to create a unit region ink drop map by determining whether ink drops fall on the unit bitmap according to each position. The step of analyzing the coordinates of each of the multiple nozzles in a first direction and in a second direction on the full-bit map, wherein the coordinates in the first direction and the coordinates in the second direction are represented as binary numbers; as well as The step of mapping the lower m bits of the binary number of the coordinates in the first direction from the rightmost position and the lower n bits of the binary number of the coordinates in the second direction to the ink droplet map of the unit area to determine whether the ink is ejected from the multiple nozzles.

12. The inkjet printing method according to claim 11, wherein, The unit bitmap includes P coordinates in the first direction and Q coordinates in the second direction. The P is 2 m , The Q is 2 n , The m and n are natural numbers.

13. The inkjet printing method according to claim 12, wherein, The m and the n are the same.

14. The inkjet printing method according to claim 13, wherein, The value of m and the value of n are 9.

15. The inkjet printing method according to claim 12, wherein, The unit bitmap comprises P×Q unit quadrilaterals. The length of one side of the unit quadrilateral is less than 1 μm.

16. The inkjet printing method according to claim 12, wherein, The length of the substrate in the first direction is I times the length of the unit region in the first direction. The length of the substrate in the second direction is J times the length of the unit region in the second direction. The substrate comprises I×J regions. The I×J regions have the same pattern. In the step of designating the unit region, any one of the I×J regions is designated as the unit region.

17. The inkjet printing method according to claim 12, further comprising: The step of ejecting ink from multiple nozzles The time to analyze the coordinates of each of the multiple nozzles and determine whether or not ink is ejected is shorter than the time it takes for the multiple nozzles to eject ink.

18. The inkjet printing method according to claim 17, wherein, During the period when the multiple nozzles are ejecting ink, the coordinates of each of the multiple nozzles in the next time step are analyzed and a decision is made on whether or not ink is ejected.

19. The inkjet printing method according to claim 12, wherein, The substrate includes a plurality of first color pixels, a plurality of second color pixels, and a plurality of third color pixels. The first color ink is ejected across the entire area of ​​the substrate, corresponding to the first color pixel. The second color ink is ejected across the entire area of ​​the substrate, corresponding to the second color pixel. A third color ink is ejected across the entire area of ​​the substrate, corresponding to the third color pixel.

20. The inkjet printing method according to claim 12, wherein, The second direction is perpendicular to the first direction. The plurality of nozzles are aligned in a direction inclined relative to the first direction and the second direction. The plurality of nozzles are fixed to the inkjet head. The direction of travel of the inkjet head is inclined relative to the first direction and the second direction.

Images