Frequency modulated web multi-pass printing method

Abstract

The application discloses a kind of frequency modulation network multi-channel printing method, including computer color processing, silk screen plate making, ink deployment and silk screen printing;According to the digital processing of target pattern, the target pattern is divided into multiple monochrome pattern data, and pixelated processing is formed into monochrome dot array data, according to monochrome pattern data and monochrome dot array data respectively deploy ink and make silk screen plate, and multiple silk screen printing machines are combined to form multi-channel printing architecture, through the monochrome ink formed by deployment and silk screen plate, in turn print the printing material to obtain clear and have the target pattern of gradient color.The application divides the target pattern into multiple monochrome pattern data according to the Lab value of target pattern, and after pixelating multiple monochrome pattern data, according to the L value of Lab value, the monochrome dot distribution density in each pixel point is determined to form monochrome dot array data, to make the silk screen plate of mesh density distribution, so as to realize clear printing and have the target pattern of gradient color.

Description

Technical Field

[0001] This invention relates to the field of screen printing technology, specifically to a multi-channel printing method for frequency modulation screens. Background Technology

[0002] FM screen printing is a type of screen printing method that changes the density of ink distribution after printing by adjusting the mesh density of the screen, thereby altering the resolution and depth of the pattern. Printing color patterns is a more challenging aspect of conventional FM screen printing. When printing color patterns, a multi-color, multi-plate, multi-channel printing method is typically used, where multiple screens use multiple colors sequentially to create a composite color pattern on the substrate.

[0003] However, as packaging designs become increasingly trendy, some designs feature different shades of the same color, such as dark blue and light blue, or dark red and light red, creating a gradient in color. While conventional multi-channel FM screen printing can print color designs using a multi-color, multi-plate composite method, the fixed mesh size of the screen makes it difficult to vary the density of the printed design in localized areas. Consequently, conventional multi-channel FM screen printing struggles to clearly print designs with gradient colors.

[0004] Therefore, when printing multi-channel FM screen printing patterns, the fixed mesh size of the screen makes it difficult to change the density of the printed pattern in local areas, resulting in a lack of clear printing of patterns with gradient colors. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-channel printing method for frequency modulation screens, in order to solve the technical problem in the prior art that the overall size of the screen mesh is fixed and difficult to change, resulting in the difficulty of printing patterns with gradient colors in local areas due to density variations.

[0006] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution:

[0007] A method for multi-channel printing of frequency modulation screens includes computer color processing, screen printing plate making, ink preparation, and screen printing;

[0008] The computer color processing includes:

[0009] The target pattern of the design is digitally color-separated, and the digital target image in Lab color mode is divided into multiple groups of monochrome pattern data using a color separation algorithm.

[0010] Each set of monochrome pattern data matrix is ​​pixelated to obtain multiple pixels, and the brightness distribution data of each set of monochrome pattern data is determined according to the Lab value of each set of monochrome pattern data. Multiple monochrome points with the same or different density are simulated in each pixel point through the brightness distribution data, and the multiple monochrome points constitute monochrome dot matrix data.

[0011] Multiple sets of monochrome pattern data and multiple sets of monochrome dot matrix data are combined into a database file;

[0012] The screen printing process includes:

[0013] Read multiple sets of monochrome dot matrix data from the database file, and use laser plate making method based on the minimum spacing of the monochrome dot matrix data to make multiple screen printing plates.

[0014] Multiple screen printing plates are respectively installed in printing units within multiple screen printing machines, and the multiple screen printing plates within the multiple screen printing machines constitute a multi-channel printing architecture;

[0015] The ink preparation includes:

[0016] Color data of the substrate surface is obtained using a color sampling instrument, and multiple sets of monochrome pattern data in the database file are read. The Lab value of the color data is compared with the Lab value of each set of monochrome pattern data to obtain color difference data.

[0017] Ink is mixed according to the color difference data and each set of monochrome pattern data to obtain multiple sets of calibrated monochrome inks;

[0018] The screen printing includes:

[0019] Multiple screen printing machines are arranged in the printing sequence, and drying equipment is set up in the area between two adjacent screen printing machines for transferring the printed material;

[0020] Multiple sets of monochrome inks are placed into printing units within multiple screen printing machines according to a corresponding relationship. The screen printing machines then quantitatively deliver the monochrome inks to the corresponding screen plates.

[0021] Multiple screen printing machines sequentially print the monochrome ink onto the surface of the substrate through the corresponding screen plates, and the ink on the surface of the substrate is dried during the transfer process between two adjacent screen printing machines;

[0022] The screen printing step and the ink mixing step can be performed in parallel.

[0023] As a preferred embodiment of the present invention, the method for dividing the target pattern into multiple groups of monochrome pattern data in the computer color processing step includes:

[0024] The target pattern is input into the color separation software, which then converts the target pattern into the Lab color mode.

[0025] The color separation software uses a color separation algorithm with the a and b values ​​of the Lab value as the color separation reference to convert the target pattern into multiple monochrome pattern data.

[0026] As a preferred embodiment of the present invention, during the color separation process, the regions where the a and b values ​​of the Lab values ​​of the target pattern are equal are the same group of colors and form the same group of monochrome pattern data, while the regions where the a and b values ​​of the Lab values ​​are unequal are different groups of colors and form different groups of monochrome pattern data.

[0027] As a preferred embodiment of the present invention, the target pattern is divided into 4 to 7 groups of monochrome pattern data.

[0028] As a preferred embodiment of the present invention, the method for forming the monochrome dot matrix data from the monochrome pattern data includes:

[0029] The monochrome pattern data is placed on the matrix pixel background to form a plurality of the pixels;

[0030] Based on the portion of the monochrome pattern data whose Lab value L value is located within the pixel, the average L value within each pixel is calculated, thereby obtaining the average L value within each pixel;

[0031] In the blank pattern data, using the color of the monochrome pattern data, and based on the average L value within each pixel, monochrome dot matrix data with the same or different densities are formed within multiple pixels.

[0032] As a preferred embodiment of the present invention, each pixel matrix is ​​equally divided into multiple measurement grids, and the L value of the Lab value of the monochrome pattern data at the center point of each measurement grid is taken as the L value of the measurement;

[0033] The average L value of each pixel is obtained by averaging the measured L values ​​of multiple measurement grids.

[0034] As a preferred embodiment of the present invention, the specifications of the pixels are preset according to the printing resolution requirements. When the difference between the average L value of the pixels and one of the measured L values ​​is greater than a preset threshold, the pixels are automatically adjusted to four smaller specifications.

[0035] As a preferred embodiment of the present invention, the method for automatically adjusting the pixels to four smaller sizes includes:

[0036] Among the pixels where the difference between the average L value and any calculated L value is greater than a preset threshold, the pixels are divided into smaller pixels by a centered cross division, and the calculated L value and average L value of the smaller pixels are calculated again.

[0037] After comparing the measured L value and the average L value of the smaller size pixel, if the difference between the average L value and any measured L value is greater than a preset threshold, the smaller size pixel is further cross-divided and measured and compared again.

[0038] Segmentation stops when the pixel segmentation reaches the preset minimum size or when the difference between the average L value of the new pixel and any calculated L value is less than or equal to a preset threshold.

[0039] The area of ​​the smallest pixel is greater than the area of ​​the monochrome pixel.

[0040] As a preferred embodiment of the present invention, after the pixel reaches a preset minimum size, and the difference between the average L value of the pixel with the minimum size and any calculated L value is still greater than a preset threshold, the calculated L values ​​of multiple measurement grids within the pixel are obtained, and the calculated L values ​​of the measurement grids are used as the basic unit for simulating multiple monochrome points.

[0041] Alternatively, after the pixel reaches a preset minimum size, and the difference between the average L value of the pixel at the minimum size and any calculated L value is less than or equal to a preset threshold, the average L value of the pixel is used as the basic unit for simulating multiple monochrome points.

[0042] The area of ​​the measuring grid is greater than the area of ​​the monochrome point.

[0043] As a preferred embodiment of the present invention, when the average L value of the pixel is used as the basic unit for simulating multiple monochrome points, the larger the average L value of the pixel, the fewer monochrome points are simulated within the pixel, and the smaller the average L value, the more monochrome points are simulated.

[0044] When the calculated L value of the measuring grid is used as the basic unit for simulating multiple monochrome points, the larger the calculated L value of the measuring grid, the fewer monochrome points are simulated within the measuring grid, and the smaller the calculated L value, the more monochrome points are simulated.

[0045] The multiple monochrome points are evenly distributed within the pixel points or the measurement grid.

[0046] Compared with the prior art, the present invention has the following advantages:

[0047] This invention divides the target pattern into multiple monochrome pattern data based on the Lab value of the target pattern, and after pixelating the multiple monochrome pattern data, determines the monochrome dot distribution density within each pixel based on the L value of the Lab value to form monochrome dot matrix data, so as to create a screen printing plate with a sparse and dense mesh, thereby achieving clear printing of target patterns with gradient colors. Attached Figure Description

[0048] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0049] Figure 1 A flowchart illustrating the steps of a multi-channel FM network printing method provided in an embodiment of the present invention;

[0050] Figure 2 A schematic diagram of a monochrome dot matrix data acquisition method for a frequency modulation network multi-channel printing method provided in an embodiment of the present invention;

[0051] Figure 3 This is a schematic diagram of the multi-channel printing process of the frequency modulation network multi-channel printing method provided in an embodiment of the present invention. Detailed Implementation

[0052] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0053] like Figure 1-3 As shown, the present invention provides a method for multi-channel printing of frequency modulation screens, including computer color processing, screen printing, ink preparation, and screen printing;

[0054] Computer color processing includes:

[0055] The target pattern of the design is digitally color-separated, and the digital target image in Lab color mode is divided into multiple groups of monochrome pattern data using a color separation algorithm.

[0056] Each set of monochrome pattern data matrix is ​​pixelated to obtain multiple pixels. The brightness distribution data of each set of monochrome pattern data is determined according to the Lab value of each set of monochrome pattern data. Multiple monochrome points with the same or different density are simulated in each pixel point through the brightness distribution data, and multiple monochrome points constitute monochrome dot matrix data.

[0057] Multiple sets of monochrome pattern data and multiple sets of monochrome dot matrix data are combined into a database file;

[0058] Screen printing includes:

[0059] Read multiple sets of monochrome dot matrix data from the database file, and use laser plate making method based on the minimum spacing of the monochrome dot matrix data to make multiple screen printing plates.

[0060] Multiple screen printing plates are installed in the printing units of multiple screen printing machines, and the multiple screen printing plates in multiple screen printing machines constitute a multi-channel printing architecture.

[0061] Ink preparation includes:

[0062] Color data of the substrate surface is obtained using a color sampling instrument, and multiple sets of monochrome pattern data are read from the database file. The Lab value of the color data is compared with the Lab value of each set of monochrome pattern data to obtain color difference data.

[0063] Ink is mixed according to color difference data and each set of monochrome pattern data to obtain multiple sets of calibrated monochrome inks;

[0064] Screen printing includes:

[0065] Multiple screen printing machines are arranged in the printing sequence, and drying equipment is set up in the area between two adjacent screen printing machines for transferring the printed material;

[0066] Multiple sets of single-color inks are placed into printing units within multiple screen printing machines according to their corresponding relationships. The screen printing machines then quantitatively deliver the single-color inks to the corresponding screen plates.

[0067] Multiple screen printing machines sequentially print single-color ink onto the surface of a substrate through corresponding screen plates, and the ink on the substrate surface is dried during the transfer process between two adjacent screen printing machines;

[0068] The screen printing and ink mixing steps can be performed in parallel.

[0069] The printing method of this embodiment mainly uses computer color processing to divide the target pattern into multiple groups of monochrome pattern data through Lab values, and pixelates each group of monochrome pattern data to form multiple pixels. The brightness distribution data within each pixel is obtained according to the Lab value of each group of monochrome pattern data, thereby simulating monochrome points with the same or different density within each pixel to form monochrome point data.

[0070] Multiple screen printing plates are made using laser plate making based on monochrome dot data. Color difference data is obtained based on monochrome pattern data and the color data of the substrate. Monochrome ink is then mixed based on the color difference data and monochrome pattern data.

[0071] Multiple screen printing plates and multiple monochrome inks are sequentially loaded into corresponding screen printing machines, and the substrate is printed and dried in a multi-channel (multi-color channel) manner according to the set sequence, so as to obtain a rich and accurate target pattern on the surface of the substrate.

[0072] Among them, the specific steps for mixing single-color inks with color difference data and single-color pattern data are as follows:

[0073] The ink is mixed according to the color difference data, and then the mixed ink is manually printed on the surface of the substrate sample.

[0074] The secondary color difference is obtained by detecting the printed color with a color sampling instrument and comparing it with the monochrome pattern data. The printing is then adjusted and compared again to ensure that the color difference between the printed color and the monochrome pattern data is within the preset error range. This completes the monochrome ink adjustment, making the color of the screen printed more accurate.

[0075] The laser plate-making method is as follows:

[0076] Based on monochrome dot matrix data, holes are precisely drilled on a non-porous polymer board using laser technology. The holes are consistent with the monochrome dot matrix data, ensuring that the resulting mesh has varying density, thus allowing for the printing of gradient colors.

[0077] FM screen printing is a type of screen printing method. By adjusting the mesh density of the screen, the distribution density of the ink after printing is changed, thereby altering the resolution and depth of the pattern. Printing color patterns is a more challenging aspect of conventional FM screen printing. When printing color patterns, a multi-color, multi-plate, multi-channel printing method is typically used, where multiple screens each use multiple colors to print, creating a composite color pattern on the substrate surface.

[0078] However, as packaging designs become increasingly trendy, some designs feature different shades of the same color, such as dark blue and light blue, or dark red and light red, creating a gradient in color. While conventional multi-channel FM screen printing can print color designs using a multi-color, multi-plate composite method, the fixed mesh size of the screen makes it difficult to vary the density of the printed design in localized areas. Consequently, conventional multi-channel FM screen printing struggles to clearly print designs with gradient colors.

[0079] Compared to conventional multi-channel frequency modulation screen printing methods, the printing method of this embodiment performs digital color separation processing on the target pattern before printing, thereby obtaining the Lab value of the target pattern. Based on the Lab value, the target pattern is divided into multiple groups of monochrome pattern data, and each group of monochrome pattern data is pixelated to form multiple groups of monochrome dot matrix data. Then, a screen plate with varying mesh density can be made based on the monochrome dot matrix data, and ink is prepared according to the monochrome pattern data, thereby enabling the clear printing of a target pattern with gradient colors on the surface of the substrate.

[0080] Among them, the method for dividing the target pattern into multiple groups of monochrome pattern data in the computer color processing steps includes:

[0081] The target pattern is input into the color separation software, which then converts the target pattern into Lab color mode.

[0082] Color separation software uses a color separation algorithm with the a and b values ​​of Lab as the color separation reference to convert the target pattern into multiple monochrome pattern data.

[0083] Specifically, the a and b values ​​of the Lab value can analyze the colors that make up the target pattern into a composite of multiple monochrome patterns. Furthermore, if the Lab value of the monochrome pattern data that makes up the target pattern is determined during the analysis process, the ratio of the basic colors (red, yellow, and blue) that make up this monochrome pattern data can be easily calculated.

[0084] In the color separation process, the regions where the a and b values ​​of the Lab values ​​of the target pattern are equal are the same group of colors and form the same group of monochrome pattern data, while the regions where the a and b values ​​of the Lab values ​​are unequal are different groups of colors and form different groups of monochrome pattern data.

[0085] Specifically, when the a value of a certain region of the target pattern is equal to the a value of another region, and the b value is also equal, the two regions have the same color. That is, the colors of the remaining regions with the same a value and b value are also the same, and these regions together constitute the monochrome pattern data of this color.

[0086] Similarly, when the a or b values ​​of two regions are not equal, they belong to different colors and are therefore two different monochrome pattern data.

[0087] Furthermore, to avoid overly complex printing, the target pattern is divided into 4 to 7 groups of monochrome pattern data, meaning that screen printing is no longer used for patterns with too many colors.

[0088] The methods for converting monochrome pattern data into monochrome dot matrix data include:

[0089] The monochrome pattern data is placed on the matrix pixel background to form multiple pixels;

[0090] Based on the L value of the Lab value of the monochrome pattern data located within the pixel, the average L value within each pixel is calculated, thus obtaining the average L value within each pixel;

[0091] In blank pattern data, using the color of monochrome pattern data, monochrome dot matrix data with the same or different densities is formed in multiple pixels based on the average L value within each pixel.

[0092] Specifically, the monochrome pattern data is divided into multiple pixel regions by a matrix of pixel boxes. The average L value of the Lab values ​​of the monochrome pattern data in each region is taken, and the monochrome point is modeled based on the average L value within each pixel.

[0093] The higher the average L value, the lighter the color, and the fewer monochrome dots are distributed within this pixel; the lower the average L value, the darker the color, and the more monochrome dots are distributed within this pixel.

[0094] The average L value is calculated as follows:

[0095] Each pixel matrix is ​​divided into multiple measurement grids, and the L value of the Lab value of the monochrome pattern data at the center point of each measurement grid is taken as the L value for measurement.

[0096] The average L value of each pixel is obtained by averaging the measured L values ​​of multiple measurement grids.

[0097] Specifically, the calculated L values ​​of the centers of multiple measurement grids within each pixel are added together and divided by the number of measurement grids to obtain the average L value.

[0098] The pixel specifications are preset according to the printing resolution requirements. When the difference between the average L value of the pixel and one of the measured L values ​​is greater than a preset threshold, it is automatically adjusted to four smaller pixel specifications.

[0099] Specifically, based on the printing resolution requirements, a minimum resolution is preset, which is the maximum size of the pixel. When the pixel is at the boundary between the monochrome pattern data and the background, the average L value within the pixel differs significantly from the measured L value at the monochrome pattern data and the measured L value at the background.

[0100] At this point, the pixel is automatically divided into four smaller pixels, so that some of the smaller pixels are completely within the monochrome pattern data, some are completely outside the monochrome pattern data, and some are still at the junction of the monochrome pattern data and the background.

[0101] Therefore, it is necessary to continue segmenting the pixels, as follows:

[0102] Methods for automatically adjusting to four smaller pixel sizes include:

[0103] In the pixels where the difference between the average L value and any calculated L value is greater than a preset threshold, the pixels are divided into smaller pixels by a centered cross division, and the calculated L value and average L value of the smaller pixels are calculated again.

[0104] After comparing the measured L value and the average L value of smaller pixels, if the difference between the average L value and any measured L value is greater than a preset threshold, the smaller pixels are further cross-divided and measured and compared again.

[0105] Segmentation stops when the pixel segmentation reaches the preset minimum size or when the difference between the average L value of the new pixels and any calculated L value is less than or equal to a preset threshold.

[0106] Among them, the area of ​​the smallest pixel is larger than the area of ​​a monochrome pixel.

[0107] Specifically, the pixels are square grids, and four identical pixels can be formed by cross-splitting. Splitting stops for pixels that are completely within the monochrome pattern data, while pixels located at the boundary between the monochrome pattern data and the background are split until they are reduced to the minimum set value.

[0108] At this point, even if the pixels located at the boundary between the monochrome pattern data and the background are printed or not, the impact on the accuracy of the printed image color is relatively small.

[0109] Therefore, after the pixel reaches the preset minimum size, and the difference between the average L value of the minimum size pixel and any calculated L value is still greater than the preset threshold, the calculated L values ​​of multiple measurement grids within this pixel are obtained, and the calculated L values ​​of the measurement grids are used as the basic unit for simulating multiple monochrome points.

[0110] When the calculated L value of the measuring grid is used as the basic unit for simulating multiple monochrome points, the larger the calculated L value of the measuring grid, the fewer monochrome points can be simulated within the measuring grid, and the smaller the calculated L value, the more monochrome points can be simulated.

[0111] At this point, the area of ​​the measuring grid is larger than the area of ​​the monochrome point, ensuring that the monochrome point can be distributed within the measuring grid.

[0112] Alternatively, after the pixel reaches the preset minimum size, and the difference between the average L value of the minimum size pixel and any measured L value is less than or equal to a preset threshold, the average L value of the pixel is used as the basic unit for simulating multiple monochrome points.

[0113] When using the average L value of a pixel as the basic unit for simulating multiple monochrome points, the larger the average L value of a pixel, the fewer monochrome points can be simulated within that pixel; conversely, the smaller the average L value, the more monochrome points can be simulated.

[0114] At this point, multiple monochrome points are evenly distributed within the pixel or measurement grid, ensuring that the monochrome points can be distributed within the measurement grid or pixel.

[0115] The above embodiments are merely exemplary embodiments of this application and are not intended to limit this application. The scope of protection of this application is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to this application within its substance and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of this application.

Claims

1. A method for printing multi-channel frequency modulation (FM) meshes, characterized in that, This includes computer color processing, screen printing, ink mixing, and screen printing. The computer color processing includes: The target pattern of the design is digitally color-separated, and the digital target image in Lab color mode is divided into multiple groups of monochrome pattern data using a color separation algorithm. The method for dividing the target pattern into multiple groups of monochrome pattern data includes: The target pattern is input into the color separation software, which then converts the target pattern into the Lab color mode. The color separation software uses a color separation algorithm with the a and b values ​​of the Lab value as the color separation reference to convert the target pattern into multiple monochrome pattern data. Each set of monochrome pattern data matrix is ​​pixelated to obtain multiple pixels, and the brightness distribution data of each set of monochrome pattern data is determined according to the Lab value of each set of monochrome pattern data. Multiple monochrome points with the same or different density are simulated in each pixel point through the brightness distribution data, and the multiple monochrome points constitute monochrome dot matrix data. The method for forming the monochrome dot matrix data from the monochrome pattern data includes: The monochrome pattern data is placed on the matrix pixel background to form a plurality of the pixels; Based on the portion of the monochrome pattern data whose Lab value L value is located within the pixel, the average L value within each pixel is calculated, thereby obtaining the average L value within each pixel; In the blank pattern data, based on the color of the monochrome pattern data and the average L value within each pixel, monochrome dot matrix data with the same or different densities are formed within multiple pixels. Multiple sets of monochrome pattern data and multiple sets of monochrome dot matrix data are combined into a database file; The screen printing process includes: Read multiple sets of monochrome dot matrix data from the database file, and use laser plate making method based on the minimum spacing of the monochrome dot matrix data to make multiple screen printing plates. Multiple screen printing plates are respectively installed in printing units within multiple screen printing machines, and the multiple screen printing plates within the multiple screen printing machines constitute a multi-channel printing architecture; The ink preparation includes: Color data of the substrate surface is obtained using a color sampling instrument, and multiple sets of monochrome pattern data in the database file are read. The Lab value of the color data is compared with the Lab value of each set of monochrome pattern data to obtain color difference data. Ink is mixed according to the color difference data and each set of monochrome pattern data to obtain multiple sets of calibrated monochrome inks; The screen printing includes: Multiple screen printing machines are arranged in the printing sequence, and drying equipment is set up in the area between two adjacent screen printing machines for transferring the printed material; Multiple sets of monochrome inks are placed into printing units within multiple screen printing machines according to a corresponding relationship. The screen printing machines then quantitatively deliver the monochrome inks to the corresponding screen plates. Multiple screen printing machines sequentially print the monochrome ink onto the surface of the substrate through the corresponding screen plates, and the ink on the surface of the substrate is dried during the transfer process between two adjacent screen printing machines; The screen printing step and the ink mixing step can be performed in parallel.

2. The method for printing a multi-channel frequency modulation network according to claim 1, characterized in that, During the color separation process, the regions where the a and b values ​​of the Lab values ​​of the target pattern are equal are considered to be in the same color group and form the same group of monochrome pattern data, while the regions where the a and b values ​​of the Lab values ​​are unequal are considered to be in different color groups and form different groups of monochrome pattern data.

3. The method for printing a multi-channel frequency modulation network according to claim 2, characterized in that, The target pattern is divided into 4 to 7 groups of monochrome pattern data.

4. The method for printing a multi-channel frequency modulation network according to claim 1, characterized in that, Each pixel matrix is ​​divided into multiple measurement grids, and the L value of the Lab value of the monochrome pattern data at the center point of each measurement grid is taken as the L value of the measurement; The average L value of each pixel is obtained by averaging the measured L values ​​of multiple measurement grids.

5. The method for printing a multi-channel frequency modulation network according to claim 4, characterized in that, The pixel specifications are preset according to the printing resolution requirements. When the difference between the average L value of the pixel and one of the measured L values ​​is greater than a preset threshold, the pixel is automatically adjusted to four smaller specifications.

6. The method for printing a multi-channel frequency modulation network according to claim 5, characterized in that, The method for automatically adjusting the pixels to four smaller sizes includes: Among the pixels where the difference between the average L value and any calculated L value is greater than a preset threshold, the pixels are divided into smaller pixels by a centered cross division, and the calculated L value and average L value of the smaller pixels are calculated again. After comparing the measured L value and the average L value of the smaller size pixel, if the difference between the average L value and any measured L value is greater than a preset threshold, the smaller size pixel is further cross-divided and measured and compared again. Segmentation stops when the pixel segmentation reaches the preset minimum size or when the difference between the average L value of the new pixel and any calculated L value is less than or equal to a preset threshold. The area of ​​the smallest pixel is greater than the area of ​​the monochrome pixel.

7. The method for printing a multi-channel frequency modulation network according to claim 6, characterized in that, After the pixel reaches the preset minimum size, and the difference between the average L value of the pixel with the minimum size and any calculated L value is still greater than the preset threshold, the calculated L values ​​of multiple measurement grids within this pixel are obtained, and the calculated L values ​​of the measurement grids are used as the basic unit for simulating multiple monochrome points. Alternatively, after the pixel reaches a preset minimum size, and the difference between the average L value of the pixel at the minimum size and any calculated L value is less than or equal to a preset threshold, the average L value of the pixel is used as the basic unit for simulating multiple monochrome points. The area of ​​the measuring grid is greater than the area of ​​the monochrome point.

8. The method for printing a multi-channel frequency modulation network according to claim 7, characterized in that, When the average L value of the pixel is used as the basic unit for simulating multiple monochrome points, the larger the average L value of the pixel, the fewer monochrome points are simulated within the pixel, and the smaller the average L value, the more monochrome points are simulated. When the calculated L value of the measuring grid is used as the basic unit for simulating multiple monochrome points, the larger the calculated L value of the measuring grid, the fewer monochrome points are simulated within the measuring grid, and the smaller the calculated L value, the more monochrome points are simulated. The multiple monochrome points are evenly distributed within the pixel points or the measurement grid.

Images