JPH11170499A - Printing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily select and establish HS data for correcting a density unevenness in a printed result. SOLUTION: A predetermined density pattern 706 is printed based on predetermined print data corrected for a density by using a head shading (HS) data 702, and a code 704 indicating the data 702 used for its upper part is printed. Thus, an effect of HS is judged by the pattern 706. When the data 702 is used for following printing, the HS data can be selected or established by the code 702.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing system, and more particularly, to head shading (hereinafter simply referred to as "HS") for correcting density unevenness caused by a print head of a printing apparatus.
).

[0002]

2. Description of the Related Art In general, in a printing apparatus using a print head having a plurality of nozzles (ink ejection ports) for ejecting ink, the shape of nozzles generated in a head manufacturing process and ink flow paths communicating with the nozzles are slightly reduced. Such variations may cause variations in the amount and direction of ink ejection between the nozzles, which may cause density unevenness in the print result. Head shading is known as a print correction method for correcting density unevenness due to variations in print elements such as nozzles and uniforming the density in a print result.

FIG. 1 is a schematic diagram of a conventional printing system for executing an HS process, and a process of creating an HS and HS data will be described with reference to FIG.

As shown in the figure, the printing system includes a document exposure system 101 for reading a read object such as a print document, an image processing unit 102 for performing image processing on a read image read by the document exposure system 101, and It has three systems of an image forming unit 103 that prints print data obtained as a result of the processing of the image processing unit 102.

The original exposure system 101 reads an original in a normal printing operation, and performs an image forming section 1 when performing HS.
A predetermined print pattern printed in step S03 is also read. The image processing unit 102 performs predetermined image processing on read data of the predetermined print pattern read by the document exposure system 101, that is, performs necessary processing such as color correction and various filtering processes. The image processing unit 10
2 performs an n-value conversion process (n = 2, 3, 4,...) Corresponding to a tone that can be output by the print head 104 when the image forming unit 103 performs copy printing. In the n-value conversion process, the image forming unit 103 that performs density correction of print data with reference to print density correction data (hereinafter also referred to as “HS data”) 105, that is, HS, An image is formed on a recording medium by the print head 104 based on the print data that has been read and subjected to the above-described processing by the image processing unit 102.

In order to execute the HS in the printing system having such a configuration, it is necessary to detect the printing characteristics of the printing head 104 used in the printing system. A predetermined print pattern based on print data having a uniform density value is printed on a printing paper, and the print result is read by a document exposure system 101 to obtain the density of each print element in the print head, and each of those print elements is obtained. Is created and stored as HS data 105 in a predetermined memory.

[0007]

However, in the conventional printing system, the means for confirming the HS effect for each print element of the print head and determining the HS data largely depends on the subjective judgment of the operator. Yes,
In addition, in the case of confirming, when arbitrarily selecting and confirming from among a plurality of HS data created under conditions of different environmental conditions, it is difficult to specify the HS data in accordance with the environmental conditions. It has been difficult to determine whether the HS data is appropriate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a printing system capable of easily confirming the HS effect and easily selecting appropriate HS data. Is to provide.

[0009]

According to the present invention, there is provided:
A printing system for performing printing on a print medium using a print head having a plurality of print elements, comprising: storage means for storing density unevenness correction data for correcting print data of each of the plurality of print elements of the print head; and ,
Means for printing a predetermined pattern using a print head based on the print data corrected by the density unevenness correction data stored in the storage means, and for correcting the print data together with the predetermined pattern. Printing means for printing a predetermined image corresponding to the used density unevenness correction data.

A reading means for reading the predetermined pattern and the predetermined image; and a judging means for judging whether the density unevenness correction data used for correcting the print data is appropriate based on a reading result of the reading means. Setting means for setting the density unevenness correction data determined by the determination means to be appropriate for use in correcting the print data.

According to the above arrangement, when a predetermined pattern is printed on the basis of the print data corrected by the density unevenness correction data, a predetermined image is printed together with the pattern. When it is determined that the uneven density correction data is appropriate, the uneven density correction data can be specified using the image, and can be used for the setting input processing. Further, by reading the predetermined image together with the predetermined pattern, it is possible to automatically determine whether or not the density unevenness correction data is appropriate and to set the same.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 2 is a block diagram showing an embodiment of a printing system to which the present invention can be applied.

The printing apparatus 201 used in the present embodiment is a color barcode label printer as shown in FIGS. 3A and 3B. The printing apparatus 201 will be described below with reference to FIGS. 3A and 3B. The structure will be described. FIG. 3A is an external perspective view of the label printer, and FIG. 3B is a diagram showing a main configuration inside the label printer.

Color barcode label printer 304
Is provided with a plurality of so-called full-line type heads 301 fixedly used in the apparatus. Printing paper 302
Is supplied by a roll holder 305 and transported by a transport system 306 having a belt or the like. Each of the heads 301 is provided with a plurality of ink ejection ports (nozzles) in a direction perpendicular to the sheet transport direction. This enlarged perspective view is shown in FIG.

As shown in FIG.
Are heads 301C for ejecting cyan ink, heads 301M for ejecting magenta ink, heads 301Y for ejecting yellow ink, and heads 301 for ejecting black ink.
K, and these print heads 301C,
As shown in FIG. 5, the nozzle arrays 301M, 301Y, and 301K have 128 nozzles as one block, and are constituted by 11 blocks of these blocks.

Referring again to FIG. 2, reader 203
Reads a predetermined print pattern printed by each print head 301 of the printing apparatus 201 in addition to the normal document reading, and the read data is used for creating HS data in the computer terminal device 202.

Next, the color bar code label printer 3
The operation from the measurement of the print characteristics of the recording head No. 04 to the creation of the HS data necessary for performing image correction based on the measurement will be described with reference to the flowchart shown in FIG. This operation is executed under the control of the computer terminal device 202.

First, each recording head 301Y, 301M, 301C,
A predetermined density pattern is printed based on print data of a constant density value for each color using 301K (step S60).
1). Thereafter, the printing result of the density pattern is read by the reading device 203 (step S602), and a density value distribution is obtained from the reading result in correspondence with each nozzle of each color print head. Every time, HS data for correcting print data is created so that the density of the print result becomes uniform (step S603). Since the creation of the HS data itself can be performed by a known method, a detailed description thereof is omitted.

The HS data created in this way is assigned as a data file name as an intermediate generation file so that the order of creation is clear, and the storage device 204
Is stored within. As described above, the process up to HS data creation (steps S601 to S603) is a common process.
Several embodiments of the data confirmation and confirmation processing will be described below.

(First Embodiment) Confirmation printing (step S604) is performed on HS data created through the above-described process to determine whether or not density correction based on the data is appropriate. FIG. 7 schematically shows a confirmation chart for confirming the HS effect. The HS pattern created based on the output density characteristics under different environmental conditions is compared with the density pattern 701 when the HS processing is not performed. A case where HS is performed using intermediate data files 702 and 703 of data is shown.

In this embodiment, the printed density pattern 706 has a "TM" mark on the upper part of the pattern to facilitate the determination of HS data used for printing the pattern.
PO1, HS "704. This makes it easy to determine that the HS data used in the pattern printing is the intermediate generation data file “TMPO1.HS”. As a result, when it is determined that the HS data is not preferable based on the obtained print result, the density pattern printing using another HS data is performed again in the same procedure, and when it is determined that the HS data is preferable, With the reference numeral 704, the HS data can be selected.

FIG. 9 shows an outline of a user interface when such an intermediate data file 702 of HS data is selected and confirmed.

In the user interface, by selecting the determination 901 of the HS file, the data file name that is ranked for each intermediately generated read is displayed in the candidate list 902. On the other hand, the code corresponding to the HS data judged to be preferable to the candidate turbulence 902, that is, the file name, is selected by referring to the code attached above the density pattern of the above-described confirmation chart. further,
Serial ID attached to the main unit to associate the selected intermediate file with the color barcode label printer
Is input as the HS data file name and the HS data is determined (step S606). This is because, when a plurality of color barcode label printers are used in parallel, the HS data, which is a characteristic unique to each printer, needs to be managed in association with the printer. Correlation and management are performed using unique information such as a printer serial ID that does not overlap between printers.

(Second Embodiment) As in the above-described embodiment, confirmation printing is performed for each color based on print data subjected to density correction using the created HS data (step S604 in FIG. 6).

In this embodiment, a density pattern 706 and a mark 705 shown in FIG. 7 are printed.

Next, the density pattern printed by applying the HS is read again by the reading device 203, and based on this, the HS data is automatically determined (step S605).

This automatic determination processing will be described with reference to the flowchart shown in FIG.

The confirmation chart on which the density pattern and the sign are printed is read by the reading device 203 (step S).
801), the density pattern portion (step S802) and the added code portion (step S803) are detected, and the code is recognized (step S804).

Here, if the code cannot be recognized, extraction and recognition are performed again within the specified number of times (step S807). If the result cannot be recognized, error processing (step S808) is performed and the processing is terminated. If the recognition can be performed normally, the HS effect is confirmed based on the extracted density pattern according to the criterion shown in FIG.

FIG. 10 is a graph showing the read density of each nozzle. The average density value ave is an average density value of the read density values of the respective nozzles. When the effect confirmation criterion of each nozzle after the HS processing is defined as ave + α to ave-α, the average density value ave between the nozzles is It is checked whether or not the difference (the hatched portion in the figure) is within the above range, and the sum of the difference Δx (> 0) between the read density values of the preceding and following nozzles is obtained. It is checked whether or not the density pattern is the minimum among the density patterns (step S805).

As a result of the confirmation, if it is confirmed that the printing state has been improved, the HS data is determined for the HS data corresponding to the above code. On the other hand, when the printing state is out of the specified range, Is the error processing (step S80)
8) is performed and the processing ends.

(Others) The present invention includes a means (for example, an electrothermal converter, a laser beam, or the like) for generating thermal energy as energy used for ink ejection, particularly in an ink jet recording system. An excellent effect is obtained in a recording head and a recording apparatus of a type in which the state of ink is changed by the thermal energy. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical structure and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recorded information and giving a rapid temperature rise exceeding the nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal on a one-to-one basis.
This is effective because air bubbles inside can be formed. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, U.S. Pat. No. 4,558,333 and U.S. Pat. No. 44,558 which disclose a configuration in which a heat acting portion is arranged in a bending region.
A configuration using the specification of Japanese Patent No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an aperture for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head.

In addition, even in the case of the serial type as described above, a recording head fixed to the apparatus main body, or an electric connection with the apparatus main body or ink from the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

Further, it is preferable to add ejection recovery means for the recording head, preliminary auxiliary means, and the like as the configuration of the recording apparatus of the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, the recording head is heated using capping means, cleaning means, pressurizing or suction means, an electrothermal transducer, another heating element or a combination thereof. Pre-heating means for performing the pre-heating and pre-discharging means for performing the discharging other than the recording can be used.

The type and number of recording heads to be mounted are, for example, not only one provided for single color ink, but also a plurality of inks having different recording colors and densities. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of the recording modes of full color by color mixture.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. In addition, in order to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the application of heat energy causes the ink to be liquefied by the application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start solidifying when it reaches the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, the ink
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent Publication No. 1260, it is also possible to adopt a form in which the sheet is opposed to the electrothermal converter in a state where it is held as a liquid or solid substance in the concave portion or through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, the form of the ink jet recording apparatus of the present invention is not limited to those used as image output terminals of information processing equipment such as computers, copying apparatuses combined with readers and the like, and facsimile apparatuses having a transmission / reception function. It may take a form.

[0042]

As described above, according to the present invention,
When a predetermined pattern is printed based on the print data corrected by the density unevenness correction data, a predetermined image is printed together with the pattern, so it is determined that the density unevenness correction data is appropriate based on the pattern. In this case, the density unevenness correction data can be specified using the image, and can be used for the setting input processing. Further, by reading the predetermined image together with the predetermined pattern, it is possible to automatically determine whether or not the density unevenness correction data is appropriate and to set the same.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a printing system that performs head shading.

FIG. 2 is a block diagram illustrating a schematic configuration of a printing system according to an embodiment of the present invention.

FIGS. 3A and 3B are an external perspective view and an internal front view of a color barcode label printer used in an embodiment of the present invention.

FIG. 4 is a perspective view of a print head used in the label printer.

FIG. 5 is a diagram illustrating a nozzle array of the print head.

FIG. 6 is a flowchart illustrating processing for creating and determining HS data according to an embodiment of the present invention.

FIG. 7 illustrates an intermediate H in one embodiment of the present invention.
It is a figure explaining the relation between S data and the code attached to the confirmation chart.

FIG. 8 is a flowchart showing an automatic HS data determination process using intermediately generated HS data according to the second embodiment of the present invention.

FIG. 9 is a diagram illustrating an intermediate generation H having a code assigned to a creation order as a data file name in the first embodiment of the present invention
FIG. 9 is an explanatory diagram of a user interface for confirming S data after confirmation printing.

FIG. 10 is a diagram illustrating a processing effect confirmation determination method after HS processing in the second embodiment.

[Explanation of symbols]

Reference Signs List 201 printing device 202 computer terminal device 203 reading device 204 storage device 301, 301Y, 301M, 301C, 301K print head 302 printing paper 306 transport system 702, 703 intermediate generation data file 704, 705 sign (mark) 706 density pattern

Claims (6)

[Claims] 1. A printing system for printing on a print medium using a print head having a plurality of print elements, comprising: correcting uneven density correction data for correcting print data of each of the plurality of print elements of the print head. Storing means for storing, based on the print data corrected by the density unevenness correction data stored in the storage means, means for printing a predetermined pattern using a print head, together with the predetermined pattern, A printing unit that prints a predetermined image corresponding to the density unevenness correction data used for correcting the print data. 2. A reading means for reading the predetermined pattern and the predetermined image, and a judging means for judging whether or not the density unevenness correction data used for correcting the print data is appropriate based on a reading result of the reading means. 2. The printing system according to claim 1, further comprising setting means for setting the density unevenness correction data determined by the determining means to be appropriate for use in correcting the print data. 3. The printing system according to claim 1, wherein the predetermined image is a code for displaying the density unevenness correction data. 4. The printing system according to claim 2, wherein the predetermined image is a mark. 5. The density unevenness data, wherein the density value of each print element in the read result is within a predetermined range, and the difference between the density values of two consecutive print elements is minimized. 3. The printing system according to claim 2, wherein it is determined that the printing is appropriate. 6. The printing element has an ink discharge port for discharging ink, and the print head generates bubbles in the ink by using thermal energy, and the ink is discharged from the ink discharge port by the pressure of the bubbles. The printing is performed by discharging.
The printing system according to any one of the above.