CN104417063B - A method and device for reducing the influence of alignment errors - Google Patents

Abstract

The present invention provides a method for reducing the impact of registration errors, including: 1) acquiring the theoretical period value of the theoretical encoding pulse signal sequence corresponding to any of the two sub-nozzles, and collecting the actual encoding pulse corresponding to the sub-nozzles signal sequence, and obtain each actual period value of the actual encoding pulse signal sequence; 2) generate a white noise sequence according to the theoretical period value of the theoretical encoding pulse signal sequence corresponding to the sub-nozzle; 3) convert each of the white noise sequence White noise is superimposed on each actual period value of the actual encoding pulse signal sequence to generate an adjusted encoding pulse signal sequence; 4) controlling the printing time of the sub-printing head according to the adjusted encoding pulse signal sequence, In this way, the influence of registration errors of the two sub-spray heads is reduced. Accordingly, means are provided for reducing the effects of registration errors. The invention can reduce the influence on human eyes caused by registration errors in existing inkjet digital printing equipment.

Description

A method and device for reducing the influence of alignment errors

technical field

The invention relates to the technical field of digital printing, in particular to a method and a device for reducing the influence of registration errors.

Background technique

Inkjet digital printing is a printing technology that has developed rapidly in recent years. It directly processes the original data and then performs inkjet to achieve the purpose of printing. For the single-pass printing method (the printing method that completes printing with one pass of paper), the position of the nozzle module is fixed, and the substrate (such as paper) is driven by the mechanical platform and moves relative to the nozzle module. When the substrate reaches the predetermined position, the nozzle module sprays mist ink droplets to the substrate under the control of the control system, thereby forming an image on the substrate.

As shown in Figure 1, the existing single-pass printing inkjet digital printing equipment contains a total of four nozzle modules, which are nozzle module 101, nozzle module 102, nozzle module 103 and The nozzle module 104 is used to spray and form four color surface images, the four colors are K (black), C (cyan), M (magenta) and Y (yellow). The working principle of the inkjet digital printing equipment is as follows: after starting the operation, the mechanical platform (including a plurality of drive shafts 105 for conveying substrates) starts to move, the encoder 106 starts to generate encoding pulse signals, and then the control system according to The encoding pulse signal controls the four nozzle modules to spray mist ink droplets to the substrate 107 sequentially, so as to obtain the desired image.

In practical applications, since the required printing width (that is, the width of the color surface image to be printed in the direction perpendicular to the paper-feeding direction) is relatively wide, each print head module is spliced by multiple sub-print heads. There are two commonly used splicing methods for nozzle modules, namely the saber corner splicing method and the horizontal splicing method. As shown in Figure 2, the horizontal splicing method is described by taking the nozzle module 101 as an example. The nozzle module 1 includes two sub-nozzles in the same width direction (that is, the direction perpendicular to the paper-feeding direction), which are sub-nozzles 1011 and sub-nozzles 1012, that is, the positions of the sub-spray head 1011 and the sub-spray head 1012 in the width direction are the same, and there is only a difference in position in the paper-feeding direction, and the sub-spray head 1011 and the sub-spray head 1012 are respectively used to print odd-numbered lines and even-numbered lines of the same color surface image , this splicing method speeds up the printing speed of each nozzle module, because the same color image is printed by the nozzle module with two sub-nozzles in the same width direction, and its printing speed is the same width direction Twice as many printhead modules as a single sub-printhead.

Using the above-mentioned horizontal splicing method, it is necessary to ensure that the positions of the patterns printed by the sub-nozzle 1011 and the sub-nozzle 1012 are aligned in the paper-feeding direction. If the pattern printed by the sub-nozzle 1011 is a hollow dot and the pattern printed by the sub-nozzle 1012 is a solid dot, then The positions of the patterns printed by the sub-nozzle 1011 and the sub-nozzle 1012 on the paper when the paper is running should be completely aligned in theory as shown in Figure 3a, that is, the distance between the patterns printed by the sub-nozzle 1011 and the sub-nozzle 1012 is always the same when the paper is moving, both are d, Therefore, the visual effect of the printed pattern is guaranteed to be good. However, in actual work, due to various factors such as the paper tension of the mechanical platform and the error of the paper movement distance collected by the encoder, there is an alignment error in the position of the pattern printed by the sub-nozzle 1011 and the sub-nozzle 1012 on the paper when the paper is moving, that is, When the paper is fed, the distance between the sub-nozzle 1011 and the sub-nozzle 1012 print patterns is not equal, as shown in Figure 3b, the registration error is: Δd _i = d _i -d, i takes 1-6 in sequence, d _i is the actual distance, and d is The theoretical spacing, the value of the registration error Δd _i fluctuates around 0 and changes in a certain way. The specific registration error curve is related to the characteristics of the mechanical platform, so that there are pattern defects on the printed proofs. Although the sub-nozzle 1011 prints hollow The solid dots printed by the dots and the sub-nozzles 1012 only occupy the width of one line, but human eyes are sensitive to regularly changing pattern defects, so the visual effect of the printed pattern is poor.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method and device for reducing the influence of registration errors in view of the above-mentioned defects in the prior art. The effect of the eyes, improve the visual effect of the printed pattern.

The technical solution adopted to solve the technical problems of the present invention:

The method for reducing the impact of alignment errors is used to reduce the impact of alignment errors of two sub-nozzles at the same position in the width direction in each nozzle module, including the following steps:

1) Obtain the theoretical period value of the theoretical coded pulse signal sequence corresponding to any of the two sub-nozzles, collect the actual coded pulse signal sequence corresponding to the sub-nozzle, and obtain each actual coded pulse signal sequence of the actual coded pulse signal sequence. Period value; said each actual period value refers to the time interval between every two adjacent pulse signals in the actual coded pulse signal sequence collected;

2) generating a white noise sequence according to the theoretical period value of the theoretical encoding pulse signal sequence corresponding to the sub-nozzle;

3) superimposing each white noise in the white noise sequence to each actual period value of the actual encoding pulse signal sequence to generate an adjusted encoding pulse signal sequence;

4) Controlling the printing timing of the sub-printing heads according to the adjusted coded pulse signal sequence, thereby reducing the influence of the registration error of the two sub-printing heads.

Preferably, in step 1), the sampling frequency of the actual coded pulse signal sequence corresponding to the sub-spray head is 80MHz-100MHz.

Preferably, the step 1) further includes: obtaining various printing speeds that can be set by the nozzle module, and the theoretical period values of the theoretical encoding pulse signal sequences corresponding to the sub-printing heads at various printing speeds, collecting various The actual encoding pulse signal sequence corresponding to the sub-printing head at the printing speed, and obtaining each actual cycle value of the actual encoding pulse signal sequence at various printing speeds;

The step 2) further includes: respectively generating a plurality of white noise sequences according to the theoretical period values of the theoretical encoding pulse signal sequences corresponding to the sub-nozzles at various printing speeds, and each white noise sequence corresponds to a printing speed;

The step 3) also includes: superimposing each white noise in the white noise sequence corresponding to each printing speed to each actual period value of the actual encoding pulse signal sequence acquired at the printing speed to generate various printing speeds down-adjusted coded pulse signal sequence;

The step 4) further includes: controlling the printing timing of the sub-printing heads at various printing speeds according to the adjusted coded pulse signal sequence at various printing speeds.

Preferably, said step 2) also includes:

Randomly obtain the original white noise sequence (N _i ), i takes 1 to m in sequence, and m is the number of white noises in the original white noise sequence (N _i );

Obtain the absolute value N _max of the maximum value in the original white noise sequence (N _i );

Then the generated white noise sequence corresponding to each printing speed is (Δt _i ) _speed , i takes 1~m in turn, m is the number of white noise in the white noise sequence (Δt _i ) _speed , and,

${\mathrm{<span\; class="notranslate">\; \&Delta;t</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; speed</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Wherein, the constant A is the white noise amplitude value, and T _speed is the theoretical cycle value of the theoretical encoding pulse signal sequence corresponding to the sub-nozzle at the printing speed corresponding to the white noise sequence (Δt _i ) _speed .

Preferably, the constant A is greater than 0 and less than or equal to 20%.

The present invention also provides a device for reducing the impact of alignment errors, which is used to reduce the impact of alignment errors of two sub-nozzles at the same position in the width direction in each nozzle module, including: an acquisition unit, a generation unit, a superposition unit and control unit;

The acquiring unit is used to acquire the theoretical period value of the theoretical encoding pulse signal sequence corresponding to any of the two sub-nozzles, acquire the actual encoding pulse signal sequence corresponding to the sub-nozzle, and acquire the actual encoding pulse signal Each actual period value of the sequence, and the acquired theoretical period value of the encoded pulse signal sequence is transmitted to the generating unit, and each actual period value of the obtained actual encoded pulse signal sequence is transmitted to the superposition unit; The actual period value refers to the time interval between every two adjacent pulse signals in the collected actual encoded pulse signal sequence;

The generation unit is used to generate a white noise sequence according to the theoretical period value of the theoretical encoded pulse signal sequence transmitted by the acquisition unit, and transmit the white noise sequence to the superposition unit;

The superposition unit is used to superimpose each white noise in the white noise sequence transmitted by the generating unit to each actual period value of the actual encoded pulse signal sequence transmitted by the acquiring unit, so as to generate an adjusted encoded pulse signal sequence, and transmit the adjusted coded pulse signal sequence to the control unit;

The control unit is used for controlling the printing timing of the sub-printing heads according to the adjusted coded pulse signal sequence transmitted by the superimposing unit, so as to reduce the influence of registration errors of the two sub-printing heads.

Preferably, the sampling frequency of the acquisition unit for the actual coded pulse signal sequence corresponding to the sub-heads is 80MHz-100MHz.

Preferably, the acquisition unit is also used to acquire various printing speeds that can be set by the nozzle module, and the theoretical period value of the theoretical encoding pulse signal sequence corresponding to the sub-jet at various printing speeds, and collect various printing speeds. The actual encoding pulse signal sequence corresponding to the sub-printing head at the speed, and obtaining each actual cycle value of the actual encoding pulse signal sequence at various printing speeds, and obtaining the theoretical encoding pulse signal at various printing speeds The theoretical period value of the sequence is transmitted to the generating unit, and the acquired actual period values of the actual encoded pulse signal sequence at various printing speeds are transmitted to the superposition unit;

The generation unit is further configured to generate a plurality of white noise sequences respectively according to the theoretical period values of the theoretical coded pulse signal sequence at various printing speeds transmitted by the acquisition unit, each white noise sequence corresponds to a printing speed, and Transmit white noise sequences corresponding to various printing speeds to the superposition unit;

The superposition unit is also used to superimpose each white noise in the white noise sequence corresponding to each printing speed transmitted by the generating unit to each actual period value of the actual encoding pulse signal sequence transmitted by the acquisition unit at the printing speed In order to generate the adjusted encoding pulse signal sequence at various printing speeds, and transmit the adjusted encoding pulse signal sequence at various printing speeds to the control unit;

The control unit is also used to control the printing timing of the sub-heads at various printing speeds according to the adjusted coded pulse signal sequence transmitted by the superimposing unit at various printing speeds.

Preferably, the generating unit is also used for:

Randomly obtain the original white noise sequence (N _i ), i takes 1 to m in sequence, and m is the number of white noises in the original white noise sequence (N _i );

Obtain the absolute value N _max of the maximum value in the original white noise sequence (N _i );

Then the generated white noise sequence corresponding to each printing speed is (Δt _i ) _speed , i takes 1~m in turn, m is the number of white noise in the white noise sequence (Δt _i ) _speed , and,

${\mathrm{<span\; class="notranslate">\; \&Delta;t</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; speed</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Wherein, the constant A is the white noise amplitude value, and T _speed is the theoretical cycle value of the theoretical encoding pulse signal sequence corresponding to the sub-nozzle at the printing speed corresponding to the white noise sequence (Δt _i ) _speed .

Preferably, in the white noise sequence (Δt _i ) _speed generated by the generating unit corresponding to each printing speed, the constant A is greater than 0 and less than or equal to 20%.

Beneficial effect:

The method and device for reducing the influence of registration errors described in the present invention take the pattern position printed by any sub-nozzle of the two sub-nozzles with the same position in the width direction of each nozzle module as a reference, and the actual code corresponding to the other sub-nozzle A white noise sequence is added to the pulse signal sequence to adjust the printing moment of another sub-nozzle, thereby adjusting the pattern position printed by another sub-nozzle, because white noise refers to the noise whose power spectral density is evenly distributed in the entire frequency domain, that is, white noise All the white noise in the sequence contains the same noise energy in the frequency bands of equal bandwidth, which is a random signal sequence with a constant power spectral density, so adjust the other according to the actual coded pulse signal sequence after adding the white noise sequence The position of the pattern printed by the sub-nozzles breaks the regular variation of the registration error of the two sub-nozzles, because the pattern printed by each sub-nozzle in the two sub-nozzles only occupies the width of a line, and compared to the regularly changing Pattern defects, human eyes are much less sensitive to irregularly changing pattern defects, thus reducing the visual impact of the alignment error of the two sub-nozzles on the human eye and improving the visual effect of the printed pattern.

Description of drawings

Figure 1 is the working principle diagram of the inkjet digital printing equipment of the existing single PASS printing method:

FIG. 2 is a schematic structural view of the nozzle module 101 using the horizontal splicing method in FIG. 1;

FIG. 3 is a schematic diagram of patterns printed by the sub-nozzle 1011 and the sub-nozzle 1012 in FIG. 2;

Wherein, Fig. 3 a is a schematic diagram of the patterns printed by the sub-nozzle 1011 and the sub-nozzle 1012 when they are theoretically aligned;

Fig. 3b is a schematic diagram when the patterns printed by the sub-nozzle 1011 and the sub-nozzle 1012 are actually aligned;

Fig. 4 is the flow chart of the method for reducing the impact of alignment errors described in Embodiment 1 of the present invention;

Fig. 5 is a schematic structural diagram of a device for reducing the influence of registration errors described in Embodiment 1 of the present invention;

FIG. 6 is a flow chart of the method for reducing the impact of registration errors described in Embodiment 2 of the present invention.

detailed description

In order to enable those skilled in the art to better understand the technical solution of the present invention, the method and device for reducing the impact of registration errors according to the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

It should be noted that in the inkjet digital printing equipment, the encoding pulse signals (pulse 1 to pulse n) generated by the same encoder in real time are used to provide printing clocks for each print head module. For example, if pulse 1 is the print head module 1 corresponds to the initial encoding pulse signal, pulse 2 is the initial encoding pulse signal corresponding to the sprinkler module 2, pulse 3 is the initial encoding pulse signal corresponding to the sprinkler module 3, and pulse 4 is the initial encoding pulse signal corresponding to the sprinkler module 4. Coded pulse signal, then pulse 1~pulse m provides printing clock for print head module 1, pulse 2~pulse m+1 provides print clock for print head module 2, pulse 3~pulse m+2 provides print clock for print head module 3 , pulse 4～pulse m+3 provides printing clock for print head module 4, n and m are both positive integers greater than 1, and n>m, it can also be said that pulse 1～pulse m, pulse 2～pulse m+1 , pulse 3~pulse m+2, pulse 4~pulse m+3 are a set of coded pulse signal sequences corresponding to nozzle module 1, nozzle module 2, nozzle module 3, and nozzle module 4 respectively, that is, each Each nozzle module corresponds to a set of coded pulse signal sequences, and each group of coded pulse signal sequences corresponding to each nozzle module overlaps. Printing starts in sequence. Due to the existence of alignment errors, a set of coded pulse signal sequences corresponding to each nozzle module is divided into a theoretical coded pulse signal sequence and an actual coded pulse signal sequence, and the theoretical coded pulse signal sequence is preset, while the actual coded pulse signal Sequences are captured in real time while printing. Moreover, in the field of digital printing technology, "line" is generally used to measure distance. "Line" refers to a line on the image dot matrix plane in the direction perpendicular to the direction of paper feeding, which also corresponds to an encoding pulse signal sent by the encoder. .

Example 1:

As shown in FIG. 4 , this embodiment provides a method for reducing the impact of registration errors, which is used to reduce the impact of registration errors of two sub-printers at the same position in the width direction in each print head module. In this embodiment, each nozzle module only includes two sub-nozzles at the same position in the width direction, and each sub-nozzle corresponds to a set of encoding pulse signal sequences (divided into theoretical encoding pulse signal sequences and actual encoding pulse signal sequences) , and the encoding pulse signal sequences corresponding to the two sub-printing heads do not overlap with each other, and each sub-printing head starts printing in sequence only when each encoding pulse signal in the corresponding encoding pulse signal sequence arrives. For example, if pulse 1 is the start code pulse signal corresponding to print head module 1, and pulse 1 to pulse m provide printing clock for print head module 1, that is, pulse 1 to pulse m is a set of codes corresponding to print head module 1 pulse signal sequence, the two sub-nozzles (sub-nozzle 1 and sub-nozzle 2) at the same position in the width direction of the nozzle module 1 are used to print the odd-numbered and even-numbered lines of the same color image, and the sub-nozzle 1 And sub-spray head 2 also correspond to a set of coded pulse signal sequences, wherein, a set of coded pulse signal sequences corresponding to sub-spray head 1 is (pulse 1, pulse 3, pulse 5...), a set of coded pulse signal sequences corresponding to sub-spray head 2 is (pulse2, pulse4, pulse6...).

The method comprises the steps of:

s101. Obtain the theoretical period value of the theoretical coded pulse signal sequence corresponding to any one of the two sub-nozzles, collect the actual coded pulse signal sequence corresponding to the sub-nozzle, and obtain each actual coded pulse signal sequence of the actual coded pulse signal sequence. period value.

The respective actual period values refer to the time interval between every two adjacent pulse signals in the collected actual coded pulse signal sequence. Each pulse in the actual encoding pulse signal sequence corresponds to each actual printing moment of the sub-heads.

Preferably, the sampling frequency of the actual encoding pulse signal sequence corresponding to the sub-spray head is 80MHz-100MHz.

s102. Generate a white noise sequence according to a theoretical period value of a theoretical encoding pulse signal sequence corresponding to the sub-sprinklers. The white noise sequence has nothing to do with the control system in the inkjet digital printing equipment, and the white noise sequence can be calculated according to the theoretical period value and using software.

s103. Superimpose each white noise in the white noise sequence to each actual period value of the actual encoding pulse signal sequence to generate an adjusted encoding pulse signal sequence.

The number of white noises in the white noise sequence should be the same as the number of actual periods of the actual coded pulse signal sequence, and each white noise in the white noise sequence corresponds to one of the actual coded pulse signal sequences actual cycle.

s104. Control the printing timing of the sub-printing head according to the adjusted coded pulse signal sequence, thereby adjusting the position of the pattern printed by the sub-printing head, and reducing the influence of the registration error of the two sub-printing heads.

It can be seen that the method for reducing the impact of registration errors described in this embodiment takes the position of the pattern printed by one of the two sub-nozzles as a reference, and adjusts the position of the pattern printed by the other sub-nozzle, thereby adjusting the position of the pattern printed by the other sub-nozzle. The pattern positions printed by other sub-nozzles with the same (or similar) positions of the nozzles in the paper-feeding direction; moreover, because a white noise sequence is added to the actual encoding pulse signal sequence corresponding to the other sub-nozzles, it breaks the The regular change of the alignment error of the two sub-nozzles reduces the visual impact of the alignment error of the two sub-nozzles on the human eye, improves the visual effect of the printed pattern, and improves the printing quality.

As shown in FIG. 5 , this embodiment also provides a device for reducing the influence of registration errors, which is used to reduce the influence of registration errors of two sub-printers at the same position in the width direction in each nozzle module. The device includes: an acquisition unit, a generation unit, a superposition unit and a control unit.

The acquiring unit is used to acquire the theoretical period value of the theoretical encoding pulse signal sequence corresponding to any of the two sub-nozzles, acquire the actual encoding pulse signal sequence corresponding to the sub-nozzle, and acquire the actual encoding pulse signal Each actual period value of the sequence, and the acquired theoretical period value of the encoded pulse signal sequence is transmitted to the generating unit, and each actual period value of the obtained actual encoded pulse signal sequence is transmitted to the superposition unit; The actual period value refers to the time interval between every two adjacent pulse signals in the collected actual coded pulse signal sequence.

Preferably, the sampling frequency of the acquisition unit for the actual coded pulse signal sequence corresponding to the sub-heads is 80MHz-100MHz.

The generation unit is used to generate a white noise sequence according to the theoretical period value of the theoretical encoded pulse signal sequence transmitted by the acquisition unit, and transmit the white noise sequence to the superposition unit.

The superposition unit is used to superimpose each white noise in the white noise sequence transmitted by the generating unit to each actual period value of the actual encoded pulse signal sequence transmitted by the acquiring unit, so as to generate an adjusted encoded pulse signal sequence, and transmit the adjusted encoded pulse signal sequence to the control unit.

The control unit is used for controlling the printing timing of the sub-printing heads according to the adjusted coded pulse signal sequence transmitted by the superimposing unit, so as to reduce the influence of registration errors of the two sub-printing heads.

Example 2:

As shown in FIG. 6 , this embodiment provides a method for reducing the influence of registration errors, which is used to reduce the influence of registration errors of two sub-printers at the same position in the width direction in each nozzle module.

The method comprises the steps of:

s201. Obtain the various printing speeds that can be set by the nozzle module, and the theoretical period values of the theoretical coded pulse signal sequences corresponding to the sub-nozzles at various printing speeds, and collect the corresponding values of the sub-nozzles at various printing speeds. An actual encoding pulse signal sequence, and obtaining each actual period value of the actual encoding pulse signal sequence at various printing speeds.

Each actual period value of the actual encoding pulse signal sequence at the various printing speeds refers to the collected time interval between every two adjacent pulse signals in the actual encoding pulse signal sequence at various printing speeds.

Generally, the highest printing speed of the existing nozzle module is 100m/min, so a variety of printing speeds can be set, such as setting 10 printing speeds, which are 10m/min, 20m/min, 30m/min, 40m/min, 50m/min, 60m/min, 70m/min, 80m/min, 90m/min and 100m/min.

s202. Generate a plurality of white noise sequences according to the theoretical period values of the theoretical coding pulse signal sequences corresponding to the sub-printing heads at various printing speeds, and each white noise sequence corresponds to a printing speed.

Preferably, said step s202 also includes:

Randomly obtain the original white noise sequence (N _i ), i takes 1 to m in sequence, and m is the number of white noises in the original white noise sequence (N _i );

Obtain the absolute value N _max of the maximum value in the original white noise sequence (N _i );

Then the generated white noise sequence corresponding to each printing speed is (Δt _i ) _speed , i takes 1~m in turn, m is the number of white noise in the white noise sequence (Δt _i ) _speed , and,

${\mathrm{<span\; class="notranslate">\; \&Delta;t</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; speed</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Wherein, the constant A is the white noise amplitude value, and T _speed is the theoretical cycle value of the theoretical encoding pulse signal sequence corresponding to the sub-nozzle at the printing speed corresponding to the white noise sequence (Δt _i ) _speed .

The white noises N ₁ , N ₂ ,...,N _m in the original white noise sequence (N _i ) have positive and negative numbers, so the generated white noise sequence (Δt _i ) corresponding to each printing speed in _speed White noise Δt ₁ , Δt ₂ ,..., Δt _m have positive and negative numbers.

The original white noise sequence (N _i ) can be directly generated by existing software, such as programming language software packages such as BASIC, FORTRAN, C, Vb and Vc++, and powerful MATLAB software packages are configured to generate Built-in function for white noise sequences.

The constant A (white noise amplitude value) can be adjusted according to the effect of the actual printed sample sheet. Preferably, the constant A is greater than 0 and less than or equal to 20%.

s203. Superimpose each white noise in the white noise sequence corresponding to each printing speed to each actual period value of the actual encoding pulse signal sequence acquired at the printing speed to generate adjusted encoding pulses at various printing speeds signal sequence.

It can be seen that if the white noise in the white noise sequence is a positive number, then the actual period value in the corresponding actual encoded pulse signal sequence will increase the absolute value of the white noise, if the white noise in the white noise sequence is If it is a negative number, the absolute value of the white noise is subtracted from the actual period value in the corresponding actual encoding pulse signal sequence, thereby adjusting the actual encoding pulse signal sequence corresponding to the white noise sequence.

s204. Control the printing timing of the sub-printing head at various printing speeds according to the adjusted coded pulse signal sequence at various printing speeds.

This embodiment also provides a device for reducing the impact of registration errors, which is used to reduce the impact of registration errors of two sub-printers at the same position in the width direction in each nozzle module. The device includes: an acquisition unit, a generation unit, a superposition unit and a control unit. The structural schematic diagram of the device is the same as the structural schematic diagram of the device described in Example 1.

The acquiring unit is used to acquire various printing speeds that can be set by the nozzle module, and the theoretical period value of the theoretical encoding pulse signal sequence corresponding to the sub-nozzles at various printing speeds, and collect various printing speeds as described below The actual encoding pulse signal sequence corresponding to the sub-nozzle, and obtaining each actual period value of the actual encoding pulse signal sequence at various printing speeds, and obtaining the theoretical period of the theoretical encoding pulse signal sequence at various printing speeds The values are transmitted to the generation unit, and the acquired actual period values of the actual encoding pulse signal sequence at various printing speeds are transmitted to the superposition unit.

The generating unit is configured to generate a plurality of white noise sequences respectively according to the theoretical period values of the theoretical encoding pulse signal sequences transmitted by the acquiring unit at various printing speeds, each white noise sequence corresponds to a printing speed, and White noise sequences corresponding to various printing speeds are transmitted to the overlay unit.

Preferably, the generating unit is also used for:

Randomly obtain the original white noise sequence (N _i ), i takes 1 to m in sequence, and m is the number of white noises in the original white noise sequence (N _i );

Obtain the absolute value N _max of the maximum value in the original white noise sequence (N _i );

Then the generated white noise sequence corresponding to each printing speed is (Δt _i ) _speed , i takes 1~m in turn, m is the number of white noise in the white noise sequence (Δt _i ) _speed , and,

${\mathrm{<span\; class="notranslate">\; \&Delta;t</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; A</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; speed</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Wherein, the constant A is the white noise amplitude value, and T _speed is the theoretical cycle value of the theoretical encoding pulse signal sequence corresponding to the sub-nozzle at the printing speed corresponding to the white noise sequence (Δt _i ) _speed .

Preferably, in the white noise sequence (Δt _i ) _speed generated by the generating unit corresponding to each printing speed, the constant A is greater than 0 and less than or equal to 20%.

The superimposing unit is used to superimpose each white noise in the white noise sequence corresponding to each printing speed transmitted by the generating unit to each actual period value of the actual encoding pulse signal sequence at the printing speed transmitted by the acquiring unit , to generate the adjusted encoding pulse signal sequences at various printing speeds, and transmit the adjusted encoding pulse signal sequences at various printing speeds to the control unit.

The control unit is also used to control the printing timing of the sub-heads at various printing speeds according to the adjusted coded pulse signal sequence transmitted by the superimposing unit at various printing speeds.

Other methods, structures and functions in this embodiment are the same as those in Embodiment 1, and will not be repeated here.

It can be understood that, the above embodiments are only exemplary embodiments adopted for illustrating the principle of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims (10)

1. reduce a method of overlapping neat error effect, for reducing the impact of two neat errors of sub-nozzle set that position is identical on fabric width direction in each shower nozzle module, it is characterized in that, comprise the steps:

1) the theoretical periodic quantity of the theoretical code sequences of pulsed signals that arbitrary sub-shower nozzle is corresponding in described two sub-shower nozzles is obtained, gather the actual coding sequences of pulsed signals that described sub-shower nozzle is corresponding, and obtain each actual cycle value of described actual coding sequences of pulsed signals; Each actual cycle value described refers to the time interval in the described actual coding sequences of pulsed signals of collection between every two successive pulse signals;

2) white noise sequence is generated according to the theoretical periodic quantity of theoretical code sequences of pulsed signals corresponding to described sub-shower nozzle;

3) each white noise in described white noise sequence is added in each actual cycle value of described actual coding sequences of pulsed signals respectively, to generate the coded pulse signal sequence after adjustment;

4) control the printing moment of described sub-shower nozzle according to the coded pulse signal sequence after described adjustment, thus reduce the neat error effect of cover of described two sub-shower nozzles.

2. method according to claim 1, is characterized in that, in step 1), the sample frequency of the actual coding sequences of pulsed signals that described sub-shower nozzle is corresponding is 80MHz ~ 100MHz.

3. method according to claim 1, is characterized in that,

Described step 1) also comprises: obtain the multiple print speed that described shower nozzle module can be arranged, the theoretical periodic quantity of the theoretical code sequences of pulsed signals corresponding with sub-shower nozzle described under various print speed, the actual coding sequences of pulsed signals that under gathering various print speed, described sub-shower nozzle is corresponding, and each actual cycle value of described actual coding sequences of pulsed signals under obtaining various print speed;

Described step 2) also comprise: the theoretical periodic quantity according to theoretical code sequences of pulsed signals corresponding to sub-shower nozzle described under various print speed generates multiple white noise sequence, the equal corresponding a kind of print speed of each white noise sequence respectively;

Described step 3) also comprises: in each actual cycle value of the actual coding sequences of pulsed signals obtained under this print speed that is added to respectively by each white noise in white noise sequence corresponding for often kind of print speed, to generate the coded pulse signal sequence under various print speed after adjustment;

Described step 4) also comprises: control the printing moment of described sub-shower nozzle under various print speed according to the coded pulse signal sequence after adjustment under various print speed.

4. method according to claim 3, is characterized in that,

Described step 2) also comprise:

Original white noise sequence (the N of random acquisition _i), i gets 1 ~ m successively, and m is original white noise sequence (N _i) in the number of white noise;

Obtain original white noise sequence (N _i) in the absolute value N of maximum _max;

White noise sequence corresponding to the often kind of print speed then generated is (Δ t _i) _speed, i gets 1 ~ m successively, and m is white noise sequence (Δ t _i) _speedthe number of middle white noise, and,

${\mathrm{\&Delta;t}}_i=\frac{N_i}{N_{\max }}*A*T_{\mathrm{speed}}---\left(1\right)$

Wherein, constant A is white noise amplitude value, T _speedfor white noise sequence (Δ t _i) _speedthe theoretical periodic quantity of the theoretical code sequences of pulsed signals that described sub-shower nozzle is corresponding under corresponding print speed.

5. method according to claim 4, is characterized in that, described constant A is greater than 0 and is less than or equal to 20%.

6. reduce the device overlapping neat error effect, for reducing the impact of two neat errors of sub-nozzle set that position is identical on fabric width direction in each shower nozzle module, it is characterized in that, comprising: acquiring unit, generation unit, superpositing unit and control unit;

Described acquiring unit is for obtaining the theoretical periodic quantity of the theoretical code sequences of pulsed signals that arbitrary sub-shower nozzle is corresponding in described two sub-shower nozzles, gather the actual coding sequences of pulsed signals that described sub-shower nozzle is corresponding, with each actual cycle value obtaining described actual coding sequences of pulsed signals, and the theoretical periodic quantity of the described theoretical code sequences of pulsed signals obtained is transferred to generation unit, each actual cycle value of the described actual coding sequences of pulsed signals obtained is transferred to superpositing unit; Each actual cycle value described refers to the time interval in the described actual coding sequences of pulsed signals of collection between every two successive pulse signals;

Described generation unit is used for generating white noise sequence according to the theoretical periodic quantity of the described theoretical code sequences of pulsed signals of acquiring unit transmission, and described white noise sequence is transferred to superpositing unit;

In described superpositing unit each actual cycle value for the described actual coding sequences of pulsed signals of acquiring unit transmission that each white noise in the described white noise sequence of generation unit transmission is added to respectively, to generate the coded pulse signal sequence after adjustment, and by the coded pulse signal sequence transmission after described adjustment to control unit;

Described control unit is used for the printing moment that the coded pulse signal sequence after according to the described adjustment of superpositing unit transmission controls described sub-shower nozzle, thus reduces the neat error effect of cover of described two sub-shower nozzles.

7. device according to claim 6, is characterized in that, the sample frequency of described acquiring unit to actual coding sequences of pulsed signals corresponding to described sub-shower nozzle is 80MHz ~ 100MHz.

8. device according to claim 6, is characterized in that,

Described acquiring unit is also for obtaining the multiple print speed that described shower nozzle module can be arranged, the theoretical periodic quantity of the theoretical code sequences of pulsed signals corresponding with sub-shower nozzle described under various print speed, the actual coding sequences of pulsed signals that under gathering various print speed, described sub-shower nozzle is corresponding, with each actual cycle value of described actual coding sequences of pulsed signals under the various print speed of acquisition, and the theoretical periodic quantity of the described theoretical code sequences of pulsed signals under the various print speed obtained is transferred to generation unit, each actual cycle value of described actual coding sequences of pulsed signals under the various print speed obtained is transferred to superpositing unit,

Described generation unit also generates multiple white noise sequence respectively for the theoretical periodic quantity of the described theoretical code sequences of pulsed signals under the various print speed transmitted according to acquiring unit, the equal corresponding a kind of print speed of each white noise sequence, and white noise sequence corresponding for various print speed is transferred to superpositing unit;

Described superpositing unit also for each white noise in white noise sequence corresponding to often kind of print speed that generation unit is transmitted be added to respectively acquiring unit transmission this print speed under described actual coding sequences of pulsed signals each actual cycle value in, to generate the coded pulse signal sequence under various print speed after adjustment, and by the coded pulse signal sequence transmission after adjustment under various print speed to control unit;

Described control unit also controls the printing moment of described sub-shower nozzle under various print speed for the coded pulse signal sequence after adjustment under the various print speed transmitted according to superpositing unit.

9. device according to claim 8, is characterized in that,

Described generation unit also for:

Original white noise sequence (the N of random acquisition _i), i gets 1 ~ m successively, and m is original white noise sequence (N _i) in the number of white noise;

Obtain original white noise sequence (N _i) in the absolute value N of maximum _max;

White noise sequence corresponding to the often kind of print speed then generated is (Δ t _i) _speed, i gets 1 ~ m successively, and m is white noise sequence (Δ t _i) _speedthe number of middle white noise, and,

${\mathrm{\&Delta;t}}_i=\frac{N_i}{N_{\max }}*A*T_{\mathrm{speed}}---\left(1\right)$

Wherein, constant A is white noise amplitude value, T _speedfor white noise sequence (Δ t _i) _speedthe theoretical periodic quantity of the theoretical code sequences of pulsed signals that described sub-shower nozzle is corresponding under corresponding print speed.

10. device according to claim 9, is characterized in that,

White noise sequence (the Δ t that often kind of print speed that described generation unit generates is corresponding _i) _speedin, constant A is greater than 0 and is less than or equal to 20%.