Inkjet printer nozzle positioning chart and media

Abstract

The application discloses a kind of inkjet printer nozzle positioning diagram, processing device and medium, it relates to printing, printer field.The inkjet printer nozzle positioning diagram is made of one or more than one coding area 110, each coding area is made of one or more than one nozzle positioning unit 104, the nozzle positioning unit is made of optional start section 201, mandatory coding section 202 and optional end section 203.The present application has the following advantages: convenient to use, nozzle number information is encoded in the printed image, which can be used in the printer nozzle color difference correction system to quickly and automatically identify the nozzle to which the printed image pixel belongs, i.e., to locate which nozzle printed the pixel.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of printers, in particular to an inkjet printer nozzle positioning map and medium. BACKGROUND

[0002] The inkjet printer, especially the industrial inkjet printer, has been widely used in the fields of advertising, printing, packaging, etc., and is the high-tech equipment in the current printing and packaging industry.

[0003] At present, most inkjet printers use piezoelectric ceramic nozzles as print heads. The piezoelectric ceramic nozzle has the advantages of on-demand printing, high printing precision, and can be applied to various inks. With the development of technology, the resolution of the piezoelectric ceramic nozzle is getting higher and higher, and the ink volume of the ink droplet is getting smaller and smaller. For example, the minimum ink droplet of a typical 600DPI piezoelectric ceramic nozzle reaches 5pL (1pL=10e-12L), and even higher precision nozzles can reach 2pL level. The higher the precision of the nozzle, the more precise the nozzle, and the smaller the aperture. With the increase of use time, the nozzle may be blocked or partially blocked, causing no ink or reduced ink volume, and further causing color difference in the printed image.

[0004] To solve the color difference problem caused by nozzle blockage or partial blockage, it is necessary to accurately measure the ink volume change of each nozzle in the print head. To solve the above technical problem, a test image can be printed by a printer, and then the printed image is converted into an electronic image document by a scanner, and the state of each nozzle is determined by analyzing the electronic image document.

[0005] Application No. CN201711284071.9 mentions a faulty nozzle test chart, which is a vertical straight line and does not contain nozzle coding information. When a printer has a large number of nozzles and needs to print the test chart multiple times to cover all the nozzles, the working state of the nozzles cannot be directly obtained by analyzing the scanned image of the printed matter.

[0006] To solve the above technical problem, the present application proposes an inkjet printer nozzle positioning map. By using the present application, the nozzle coding information is hidden in the inkjet printer nozzle positioning map, and by certain technical processing, the information of the nozzle to which the pixel of the scanned image of the printed matter belongs can be obtained, which can be used in the inkjet printer nozzle color difference correction system to quickly and automatically identify the nozzle to which the pixel of the printed image belongs, that is, to locate which nozzle prints the pixel. SUMMARY

[0007] The technical problem to be solved by the present application is the positioning problem of the print head of an inkjet printer, and a print head positioning pattern, device and medium are provided to quickly and automatically identify the print head to which a pixel of a printed image belongs, i.e., to locate which print head prints the pixel.

[0008] For the convenience of description, the present application is described with the white pixel value being 0, and for the case of the white pixel value being 255 (8-bit image), the corresponding value is simply inverted, i.e., 255-P(x,y), P(x,y) is the pixel value, which does not affect the understanding of the present application.

[0009] The present application provides a print head positioning pattern of an inkjet printer, characterized in that the print head positioning pattern of the inkjet printer is composed of one or more than one coding area 110, each coding area is composed of one or more than one print head positioning unit 104, the print head positioning unit is composed of an optional start segment 201, a mandatory coding segment 202 and an optional end segment 203.

[0010] The print head positioning unit is further characterized in that

[0011] The width 304 of the print head positioning unit is greater than or equal to 3 pixels, the width of the print head positioning unit refers to the number of print heads required to print the print head positioning unit, and only the value of the pixel belonging to the current print head is allowed to be greater than 0, and the values of the pixels belonging to other non-current print heads are 0, the pixel belonging to the current print head refers to the pixel printed by the print head belonging to the current print head positioning unit.

[0012] The print head positioning units of different print heads have different codes.

[0013] Preferably, the print head positioning unit is further characterized in that

[0014] The start segment identifies the start of the coding segment, and corresponds to a line segment area composed of one or more pixels in the print head positioning pattern of the inkjet printer, the number of pixels with a value greater than or equal to T2 in the start segment is greater than or equal to 1.

[0015] The coding segment 202 is composed of a plurality of binary code bits, the code is the print head number for printing the pixel, the i-th code bit corresponds to a line segment area composed of Ni pixels in the print head positioning pattern of the inkjet printer, among the Ni pixels, Ni1 pixels have a pixel value <Ti1, Ni2 pixels have a pixel value >=Ti1, Ni=Ni1+Ni2, wherein Ni1 is greater than or equal to 0, Ni2 is greater than 0, and i=[0,1,…M-1], M is the number of code bits.

[0016] The end segment marks the end of the coding segment and corresponds to a line segment area composed of one or more pixels in the inkjet printer nozzle positioning diagram. The number of pixels with a pixel value greater than or equal to T3 in the end segment is greater than or equal to 1.

[0017] For subtractive color systems, Ti1, T2, and T3 are taken to be greater than 0.

[0018] Preferably, the representation of each code point includes, but is not limited to:

[0019] The first method: Ni2 < T4 represents 0, Ni2 >= T4 represents 1, and T4 is the code bit decision threshold, with a value of T4=[1,Ni]. Or conversely, Ni2 < T4 represents 1, and Ni2 >= T4 represents 0.

[0020] The second method: s = SUM(Pik), where s < T5 represents 0, and s >= T5 represents 1, where SUM() is the summation function, Pik is the k-th pixel in the pixel sequence printed by the i-th nozzle positioning unit, k=[0, Ni-1], and T5 is the decision threshold, which can be set as needed. Alternatively, if s < T5, it represents 1; if s >= T5, it represents 0.

[0021] Preferably, the encoding method of the nozzle positioning unit encoding segment includes, but is not limited to, original code, inverse code, or complement code.

[0022] Preferably, in the same coding area, the codes of adjacent nozzle positioning units are arranged in an alternating manner of original code, inverse code, or complement code, which can increase the code distance between adjacent nozzle positioning unit codes, thereby improving the recognition rate.

[0023] Specifically, multiple nozzle positioning units with the same nozzle are combined into a logical nozzle positioning unit to increase the coding segment length, and nozzle coding is performed in the coding segment of the logical nozzle positioning unit.

[0024] Furthermore, different nozzle positioning units are arranged randomly and cascaded to form logical nozzle positioning units to achieve nozzle encoding. In this case, the combination of all nozzle positioning units will be regarded as a single encoding area. This situation should still be considered within the scope of the present invention.

[0025] To address the problem of locating the nozzles to which the pixels of a scanned image of a substrate belong in an inkjet printer, this invention also proposes a computer-readable storage medium, characterized in that the storage medium stores the nozzle positioning map of the inkjet printer proposed in this invention.

[0026] The present invention is easy to use. The nozzle number information is encoded in the printed image and can be used in the printer nozzle color difference correction system to quickly and automatically identify the nozzle to which the pixel of the printed image belongs, that is, to locate which nozzle printed the pixel. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the nozzle positioning of an inkjet printer proposed in this invention;

[0028] Figure 2 This is a schematic diagram of the nozzle positioning unit with a width of 3 proposed in this invention;

[0029] Figure 3 This is a schematic diagram of the nozzle positioning of an inkjet printer with a width of 3 and a 4-bit encoding bit, according to Embodiment 1 of the present invention.

[0030] Figure 4 This is a schematic diagram of a nozzle positioning unit with a width of 3 and ink volume limitation according to Embodiment 1 of the present invention;

[0031] Figure 5 This is a schematic diagram of the nozzle positioning unit coding segment with the high bit on the left in Embodiment 1 of the present invention;

[0032] Figure 6 This is a schematic diagram of the nozzle positioning unit coding segment with the high bit on the right in Embodiment 1 of the present invention;

[0033] Figure 7 This is a schematic diagram of the nozzle positioning of an inkjet printer with a width of 5 according to Embodiment 2 of the present invention;

[0034] Figure 8 This is a 5-width image segment of an inkjet printer nozzle positioning image with ink volume limitation, as described in Embodiment 2 of the present invention.

[0035] Figure 9 This is a schematic diagram of the nozzle positioning of an inkjet printer composed of a logic nozzle positioning unit, according to Embodiment 3 of the present invention. Detailed Implementation

[0036] The features and exemplary embodiments of various aspects of the present invention will now be described in detail. To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be practiced without some of these specific details.

[0037] The specific embodiments of the present invention are described in detail below.

[0038] Example 1: Nozzle positioning diagram of an inkjet printer with a width of 3

[0039] like Figure 1As shown, 103 is a schematic diagram of the nozzle positioning map of an inkjet printer with a width of 3. For the convenience of description, the inkjet print head 101 and its nozzles 102 are described above the nozzle positioning map 103 of the inkjet printer. The printing direction of the nozzle positioning map of the inkjet printer is perpendicular to the nozzle arrangement direction. In this embodiment, each nozzle is responsible for printing a column of pixels in the nozzle positioning map of the inkjet printer, and this column of pixels is also called the attributed pixels of this nozzle.

[0040] In this embodiment, the nozzle positioning map of the inkjet printer consists of a first coding area 110, a second coding area 111, and a third coding area 112. Each coding area consists of multiple nozzle positioning units 104. In this embodiment, the width of the nozzle positioning unit is 3, that is, each nozzle positioning unit covers 3 nozzles or 3 pixels, such as the nozzle positioning unit 104 of the nth nozzle. In the nozzle positioning unit 104 of the nth nozzle, only the pixel values of the column corresponding to the nth nozzle are allowed to be greater than 0, and the pixel values of the two adjacent columns of nozzles are 0.

[0041] To determine the working state of each nozzle by analyzing the nozzle positioning map of the inkjet printer, the primary task is to identify which nozzle prints each pixel in the nozzle positioning map of the inkjet printer. For this purpose, the present invention proposes a method of encoding the pixel sequence within the nozzle positioning unit for identification.

[0042] As Figure 2 shown, the nozzle positioning unit consists of a start segment, a coding segment, and an end segment, where the start segment and the end segment are optional. In this embodiment, the nozzle positioning unit consists of a start segment 201, a coding segment 202, and an end segment 203.

[0043] The start segment identifies the start of the coding segment and corresponds to a line segment area composed of one or more pixels in the nozzle positioning map of the inkjet printer. The number of pixels with pixel values greater than T2 in the start segment is greater than or equal to 1.

[0044] The coding segment 202 consists of multiple binary bits. The code is the nozzle number for printing the pixel. Different nozzles have different codes. The ith code bit corresponds to a line segment area composed of Ni pixels in the nozzle positioning map of the inkjet printer. Among the Ni pixels, the pixel values of Ni1 pixels < Ti1, and the pixel values of Ni2 pixels >= Ti1, Ni = Ni1 + Ni2, where Ni1 is greater than or equal to 0, Ni2 > 0, and i = [0, 1,... M - 1], and M is the number of coding bits.

[0045] The end segment identifies the end of the coding segment and corresponds to a line segment area composed of one or more pixels in the nozzle positioning map of the inkjet printer. The number of pixels with pixel values greater than T3 in the end segment is greater than or equal to 1.

[0046] For subtractive color systems, Ti1, T2, and T3 are taken to be greater than 0.

[0047] like Figure 4 As shown, the nozzle positioning unit is an 8-bit image with pixel values ​​ranging from [0, 255]. The thresholds Ti1, T2, and T3 for each segment are set to [1, 254]. The starting segment occupies 4 pixels, each code bit occupies 4 pixels (Ni = 4), and the ending segment occupies 4 pixels. Specifically, the first and third pixels of the starting segment have a value of 255, while the second and fourth pixels have a value of 0. In the encoded segment, the first code bit has all pixels 0 (N11 = 4, N12 = 0), indicating that the highest bit (MSB) is 0. The first and third pixels of the second code bit have a value of 255, while the second and fourth pixels have a value of 0 (N11 = 2, N12 = 2), therefore the second highest bit is 1, and so on. This encoded value is binary 0110. This encoding method is used for nozzle ink volume limitation to prevent excessive ink output from causing ink flow and affecting the analysis and processing of the scanned image.

[0048] The coded segment, with the same pixel value layout, can represent different code values, i.e., as shown below. Figure 4 In the coded segment shown, the first code bit has all 0 pixels, i.e., N11=4 and N12=0, indicating that the highest bit MSB is 1. The first and third pixels of the second code bit have values ​​of 255, and the second and fourth pixels have values ​​of 0, i.e., N11=2 and N12=2, so the second highest bit is 0. And so on, the coded value is binary 1001.

[0049] The encoding used by the nozzle positioning unit includes, but is not limited to, original code, inverse code, or complement code.

[0050] In the same coding area, the coding of adjacent nozzle positioning units adopts the original code, inverse code, or complement code alternately, which can increase the code distance between adjacent nozzle positioning unit codes, thereby improving the recognition rate.

[0051] For a coded segment, there are two encoding orders: one is most significant bit (MSB) first (left), meaning the most significant bit is arranged immediately after the start of the segment, such as... Figure 5 As shown. Another implementation is with the most significant bit at the end (right), meaning the most significant bit of the encoding is immediately followed by the end segment, as shown below. Figure 6 As shown.

[0052] Example 2: Nozzle positioning diagram of an inkjet printer with a nozzle positioning unit width of 5.

[0053] In inkjet printing, ink spreads across the substrate due to surface tension and wettability, causing ink droplets to increase in diameter. When the image on the substrate is transferred via a scanner, more pixels are needed to hold the ink droplets from the nozzles. To accommodate high-volume printheads, this invention does not limit the maximum width of the nozzle positioning unit, but the minimum width should not be less than 3.

[0054] To accommodate high-volume ink printheads, Embodiment 2 of this invention proposes an inkjet printer nozzle positioning diagram 701 with a nozzle positioning unit width of 5, as shown in the schematic diagram. Figure 7 As shown, the inkjet printer nozzle positioning diagram consists of five coding areas 704, 705, 706, 707, and 708. Each coding area consists of multiple parallel nozzle positioning units 703. In the nozzle positioning unit, the middle column of pixels 702 is the pixel to which the nozzle of this nozzle positioning unit is responsible for printing.

[0055] Furthermore, Figure 8 An example is provided for an inkjet printing system with 20-bit encoding, capable of searching up to 2^20 nozzles, and featuring ink volume limiting, alternating original and inverse code arrangement, and nozzle positioning unit width of 5 for the inkjet printer nozzle positioning image segment.

[0056] Example 3. Nozzle positioning diagram of an inkjet printer composed of logic nozzle positioning units.

[0057] Multiple nozzle positioning units with the same nozzle are combined into a logical nozzle positioning unit to increase the coding segment length, and nozzle coding is performed in the coding segment of the logical nozzle positioning unit.

[0058] In extreme cases, to avoid pixel overlap due to ink coverage from different nozzles, the nozzle positioning unit length should be greater than or equal to 3. When the limit value of 3 is taken, each nozzle positioning unit becomes a 3*3 matrix unit, and only the central pixel can be used for encoding; this pixel is also called the coded pixel. Other pixels within this nozzle positioning unit are called non-coded pixels. In this case, the nozzle positioning unit has no start or end segment, and the encoding bit length is only 1 bit, allowing encoding only one nozzle. To solve the problem of insufficient encoding length, multiple nozzle positioning units with the same nozzle are cascaded. The coded pixels of the cascaded nozzle positioning units are logically connected together, and these pixels are used to carry the encoding bit, thereby increasing the encoding length and meeting the system's encoding requirements.

[0059] like Figure 9 As shown, nozzle positioning units 904, 906, and 908 of nozzle n combine to form a logical nozzle positioning unit. The coded pixels 905 of nozzle positioning unit 904, 907 of nozzle positioning unit 906, and 909 of nozzle positioning unit 908 combine to form the coded pixels of the logical nozzle positioning unit of nozzle n, used to carry coded bits. All nozzle positioning units combine to form a coding area 903.

[0060] Furthermore, different nozzle positioning units are arranged randomly and cascaded to form logical nozzle positioning units to achieve nozzle encoding. In this case, the combination of all nozzle positioning units will be regarded as a single encoding area. This situation should still be considered within the scope of the present invention.

[0061] Example 4. A storage medium for inkjet printer nozzle positioning patterns

[0062] Based on the inkjet printer nozzle positioning diagram in the above embodiments, the present invention can be implemented using a computer-readable storage medium. This computer-readable storage medium stores the inkjet printer nozzle positioning diagram proposed in this invention.

[0063] The present invention is easy to use. The nozzle number information is encoded in the printed image and can be used in the printer nozzle color difference correction system to quickly and automatically identify the nozzle to which the pixel of the printed image belongs, that is, to locate which nozzle printed the pixel.

[0064] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A nozzle positioning diagram for an inkjet printer, characterized in that, The nozzle positioning map of the inkjet printer consists of one or more coding areas, each coding area consists of one or more nozzle positioning units, and the nozzle positioning unit consists of an optional start segment, a mandatory coding segment, and an optional end segment; Among them, the characteristics of the nozzle positioning unit are further that, the width of the nozzle positioning unit is greater than or equal to 3 pixels. The width of the nozzle positioning unit refers to the number of nozzles required to print the nozzle positioning unit, and only the pixel value of the pixel where the current nozzle is located is allowed to be greater than 0, and the pixel values of other pixels that are not where the current nozzle is located are 0, that is, the pixel values corresponding to the nozzles in the adjacent columns are 0. The pixel where the current nozzle is located refers to the pixel printed by the nozzle belonging to the current nozzle positioning unit; and the nozzle positioning units of different nozzles have different encodings; The start segment identifies the start of the coding segment, corresponding to a line segment area composed of one or more pixels in the nozzle positioning map of the inkjet printer. The number of pixels with pixel values greater than or equal to T2 in the start segment is greater than or equal to 1; The coding segment consists of multiple binary code bits. The code is the nozzle number for printing the pixel. The i-th code bit corresponds to a line segment area composed of Ni pixels in the nozzle positioning map of the inkjet printer. Among the Ni pixels, the pixel values of Ni1 pixels < Ti1, the pixel values of Ni2 pixels >= Ti1, and Ni = Ni1 + Ni2. In the formula, Ni1 is greater than or equal to 0, Ni2 > 0, where i = [0, 1,... M - 1], and M is the number of coding bits; The end segment identifies the end of the coding segment, corresponding to a line segment area composed of one or more pixels in the nozzle positioning map of the inkjet printer. The number of pixels with pixel values greater than or equal to T3 in the end segment is greater than or equal to 1; For the subtractive color system, the thresholds Ti1, T2, and T3 are taken to be greater than 0.

2. The inkjet printer nozzle positioning diagram according to claim 1, characterized in that, The coding method of the coding segment of the nozzle positioning unit includes original code, inverse code, or complement code.

3. The inkjet printer nozzle positioning diagram according to claim 1, characterized in that, In the same coding area, the encodings of adjacent nozzle positioning units are arranged in an alternating manner of original code, inverse code, or complement code.

4. The inkjet printer nozzle positioning diagram according to claim 1, characterized in that, The nozzle positioning units of multiple same nozzles are combined into a logical nozzle positioning unit to increase the length of the coding segment, and nozzle coding is performed in the coding segment of the logical nozzle positioning unit.

5. A computer-readable storage medium, characterized in that, The storage medium stores the nozzle positioning map of the inkjet printer according to any one of claims 1-4.

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