JP3088387B2 - Print density adjustment method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print density adjusting method for adjusting a print density of a printing apparatus and an apparatus therefor.

[0002]

2. Description of the Related Art Conventionally, various types of printers using a TA system, a sublimation system, a melting system, a cycolor system, etc., which develop a color by energy such as heat or light, are known.

The TA type full-color printer uses a TA medium, which is a medium that develops color by applying thermal energy having a relationship between temperature and time, and prints by applying heat to a printer head.

[0004] Further, in this TA type full-color printer, the color to be produced differs depending on the amount of energy.
At this time, the printer has information data indicating how much energy should be applied to perform color development in the printer, that is, an applied energy value, and the printer applies heat to the head to perform printing while referring to the applied energy value.

However, at the time of printing, there is a problem that color is not formed at the same density even when the same energy is applied between the printer devices due to a contact state between the printer head and the TA medium and a variation in the resistance value of each printer head. . Further, there is a problem that the balance between the three basic colors constituting the full color, ie, yellow, magenta, and cyan is poor, resulting in an unnatural print result.

Therefore, as described in Japanese Patent Application Laid-Open No. Hei 7-314750, for example, a color sample is created in advance, the created data of the color sample is stored, and the sample is printed using the created data of the color sample at the time of trial printing. Create a test print, determine the density correction value of each basic color by comparing this test print with the color sample, and use the other basic colors as this density correction value, and correct based on this density correction value The density is adjusted by printing based on the applied energy value.

[0007]

However, in the density adjusting method described in Japanese Patent Application Laid-Open No. Hei 7-314750, a test print must be printed, the printing cost increases, and the test print and the color sample are used. Are compared, the density correction value of one of the basic colors is used as the density correction value of the other basic colors, so that an improvement in color balance cannot be expected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a printing density adjustment method and apparatus capable of improving the best printing condition and preventing the variation in the best printing condition. .

[0009]

According to a first aspect of the present invention, there is provided a print density adjusting method for adjusting a print density of a printing apparatus, comprising the steps of inputting an image having a plurality of density distributions different in a known density in advance. The density average value of the entire surface at each density of the printed image data is calculated and used as a density target value, the image data is printed, and the printed image data is input again as image adjustment data data. A print density adjustment method for calculating a density difference between a density and a corresponding known density of the image data, and correcting an applied energy value when printing based on the density difference.
The calculation of the density difference is performed for each density of the image data for adjustment.
On the other hand, each one in all dots of the printer head of the printing apparatus
Calculate the average value in dot units and calculate the calculated dot unit
Is calculated by calculating a density difference between the average value and the density target value . According to a second aspect of the present invention, there is provided a print density adjusting method for a plurality of basic colors of the printing apparatus according to the first aspect.
It is characterized in that the applied energy value is corrected separately
Is what you do . The print density adjusting method according to the third aspect,
The concentration according to claim 1 or 2 is known in advance.
An image having a plurality of density distributions with different
The color corresponding to the basic color to be adjusted is attached with different density
It is characterized by being . According to a fourth aspect of the present invention, there is provided a print density adjusting method according to the first or second aspect, which has a plurality of different density distributions whose densities are known in advance.
Images are gray with different densities
It is characterized by the following . Print density adjusting apparatus for a printing apparatus according to claim 5, wherein the storage in the print density adjusting device for adjusting the printing density, the image data obtained by the image the image input in advance concentration with known different concentrations in the storage unit A reading unit that calculates the density average value of the entire surface at each density of the image data, and a target value calculation processing unit that stores the density average value in the storage unit as a density target value; and prints the image data and inputs the image again. A density difference calculation processing unit that calculates a density difference between each density of the adjustment image data obtained and the corresponding known density of the image data,
A printer writing unit for correcting an applied energy value at the time of printing based on the density difference calculated by the density difference calculation processing unit, wherein the density difference calculation processing unit
Data for all densities of the printer
The average value for each dot in the
The density difference between the average dot value and the target density value
It is characterized by doing . According to a sixth aspect of the present invention, there is provided the print density adjusting device, wherein the reading unit according to the fifth aspect performs printing.
Colors corresponding to the basic colors to be adjusted
Images with multiple density distributions differing in known density
The image data obtained by the input to the storage unit
It is characterized by the following . According to a seventh aspect of the present invention, in the print density adjusting device, the reading unit according to the fifth aspect is configured such that
There are multiple density distributions with different colors at known densities.
The image data obtained by inputting the image
It is characterized by being stored in a storage unit .

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the configuration of a print density adjusting device of a TA type full-color printer according to an embodiment of the present invention will be described with reference to FIG.

In FIG. 1, reference numeral 1 denotes an input device such as a keyboard of a personal computer, that is, a personal computer. The input device 1 outputs data to be input to a density adjusting tool 2 which is software operating on the personal computer.

The density adjustment tool 2 stores density data read by a scanner 4 used for reading, for example, 90% density and 30% density print images when performing density adjustment. Storage memory 3
The scanner reading unit 21 is a reading unit that stores the data in the scanner reading storage unit 31 above.

The density adjusting tool 2 is connected to the scanner reading unit 21 and determines whether the density data read from the scanner 4 by the scanner reading unit 21 is a process for obtaining a target density or a process for performing density adjustment. A discriminating unit 22 for discriminating is connected. This determination is made by selecting which processing is to be performed by the input device 1 before starting the density adjustment.

Further, the discriminating unit 22 includes a processing unit A23 as a target value calculation processing unit for performing processing for obtaining a target density for the density data, and a processing as a density difference calculation processing unit for performing processing for performing density adjustment. Section B24 is connected.
Then, the processing unit A23 calculates the average value of the respective densities at 90% density and 30% density of the print image master as image data which is an image read by the scanner reading unit 21 and stored in the scanner reading storage unit 31. . Here, the print image master has 90% density and 3
A medium on which 0% density is printed, that is, a print medium in which, for example, the upper half surface of the medium has 90% density and the lower half surface has 30% density.

Further, the average values of these densities are set as target density values of 90% density and 30% density in the target density value storage section 32 in the storage memory 3 of the personal computer. In addition,
The calculation method of the average value of these densities is as follows.
For each% density surface, the average value of the densities of all the dots on the entire surface is calculated.

On the other hand, the processing section B24 obtains the respective average values at 90% density and 30% density of the adjustment print image as the adjustment image data stored in the scanner reading storage section 31 by the reading section 21. Here, the print image for adjustment is a medium on which a 90% -density surface and a 30% -density surface having a width corresponding to the total number of dots of the printer head are printed.

In the method of calculating these average values, an average value for each dot is obtained for all dots of the printer head. That is, for example, assuming that the printer head has 300 dots and that it is a 90% density image and a 30% density image printed by 100 lines at 300 dots, respectively, the average value is obtained by calculating 100 lines at 300 dot units. Calculate the average value. Therefore, there are 300 types of average values to be obtained, which are the number of dots of the printer head. The print image for adjustment is obtained by printing 90% density and 30% density by a printer before adjustment, and the printing method is a general printing method, and therefore the description is omitted.

The average value of each dot is compared with the density target value stored in the density target value storage unit 32 to determine the density difference, and the applied energy value is changed so as to eliminate the density difference. Correct with.

The density adjustment tool 2 includes a processing unit B2.
4 and a printer writing unit 25 for writing the corrected applied energy value generated by the processing unit B24 into the printer 5.

Next, the operation of the print density adjusting apparatus according to the embodiment will be described with reference to the flowchart shown in FIG.

First, a 90% density and a 30% density, which are print images, are set by setting a density target value or performing density adjustment.
A density print image master or an adjustment print image is set on the scanner 4 (step A1).

On the other hand, the density adjusting tool 2 is started by the input device 1, that is, two processing units A23 or B divided by the discriminating unit 22 by the density adjusting tool 2.
The determination is made by selecting with the input device 1 which of the processes 24 is to be performed (step A2).

Then, the density adjustment tool 2 is connected to the input device 1
A density print image, which is a print sample set on the scanner 4, is read in response to the start command (step A3). Thereafter, the density print image read by the scanner reading unit 21 of the density adjustment tool 2 is stored in the storage memory 3 of the personal computer.
It is stored in the upper scanner reading storage unit 31 (step A4).

Next, the determination section 22 determines whether or not to obtain a target density value.

Then, the discriminating section 22 has selected to obtain the density target value. That is, the input section 1 has already determined the 90% density and 30% density target values by the input operation of the input device 1, and determines the density target value. If it is determined that the process to be set in the target value storage unit 32 has been selected, the process proceeds to step A
In steps 1 to A4, the print image master, which is a medium on which 90% density and 30% density are printed on the surface set on the scanner 4, is read and stored in the scanner reading storage unit 31. ing.

For this reason, the selected processing unit A23 performs the processing for each of the 90% density and 30% density surfaces of the print image master stored in the scanner reading storage unit 31.
The average value of the density of all the dots on the entire surface is calculated.
Thereafter, the average values of the obtained 90% density and 30% density are stored as density target values in the density target value storage unit 32 (step A6).

Note that this density target value is necessary when detecting a density difference between the adjustment print image and the density target value. That is, before performing the density adjustment, the density target value must be set in the density target value storage unit 32 without fail. In the operation for obtaining the density target value, the density target value is registered by storing the density target value in the density target value storage unit 32 by the density adjustment tool 2, so that the first time the density adjustment system is constructed, The adjustment may be performed only when the adjustment system is changed, for example, when the scanner 4 is changed or when the scanner 4 is periodically calibrated.

On the other hand, the discrimination unit 22 has selected not to obtain the density target value, that is, the density target value storage unit 32
90% density and 30% density of the print image for adjustment with respect to the density target values of 90% density and 30% density stored in
After calculating the density difference from the density and performing the correction, when the processing unit B24, which is the process of writing the applied energy value changed by the correction to the printer 5, is determined to have been selected by the input device 1 in step 2, the processing has already been performed. In steps A1 to A4, the adjustment print image set in the scanner 4 is read and stored in the scanner reading storage unit 31.

For this reason, the selected processing unit B24 performs a one-dot unit for all dots of the printer head on each of the 90% density and 30% density surfaces of the adjustment print image stored in the scanner reading storage unit 31. Find the average value with. Then, with respect to the density target value stored in the density target value storage unit 32, it is calculated how much the density value of the average value for each dot of the printer head obtained above is different, and the applied energy value is calculated. Is corrected (step A7).

Then, the changed applied energy value is written in the memory of the printer 5 by the printer writing unit 25 (step A8).

Next, the above-described correction for changing the applied energy value is performed, for example, when the basic colors of the TA system full-color printer 5 are three colors of yellow, magenta, and cyan.
It is determined whether the same operation has been performed for each of the three colors (step A9). If it is determined that the three colors have not been corrected, the process returns to step A1. That is, in order to create various colors with the basic colors of the printer 5, this print density adjustment processing must be performed by the number of the basic colors of the printer 5. Step A
If it is determined in step 9 that the correction of three colors has already been completed,
The print density adjustment processing ends.

The printer 5 can print with the same density value as the target density by printing with reference to the corrected applied energy value.

Here, the applied energy value will be described.

The applied energy value is information as to how much energy should be added to perform color development in the printer 5. This information includes two types of information corresponding to the number of dots of the head, in which the heating level before color development is defined as the white level, and the maximum heating level, which is the level at which the color is most deeply developed, is the full color development level. If the basic colors of the printer are three colors of yellow, magenta, and cyan, the applied energy values have information of six types, that is, 2 data × 3 colors.

That is, the full color development level, which is the maximum heating level of the applied energy value, is information when printing a 100% density image, and the white level, which is the heating level before color development, is 0% density. This is information for printing a density image.

When the processing unit B24 changes the full color development level and the white level of the applied energy value, the full color development level is created from 90% density and the white level is created from 30% density. Since the upper limit of the applied energy value is determined by the characteristics of the TA medium, the applied energy values of the full color development level and the white level do not have to be created from the 100% density and the 0% density.

That is, no matter how much the applied energy value is increased, the density does not become higher than a certain density. Therefore, if the density is adjusted at 100% density, an erroneous adjustment may occur. Further, at 0%, no color development occurs, so that the density cannot be adjusted. Further, the reason why the white level density is adjusted at the 30% density instead of the 10% density is that if the density is not 30% or more, the density is too low and the scanner 4 cannot read an accurate value.

When the printer has a performance of 256 gradations, 256 gradations are realized by the respective values when the full color development level and the white level are divided into 256 equal parts. For example, since the 90% density is the 230th gradation, the applied energy value of 90% can be obtained by the following equation: 90% density applied energy value = (full color level applied energy value−white level applied energy value) Energy value) × 230/2
56. Therefore, all gradations can be handled only by the information on the applied energy values of the full color development level and the white level.

Next, a printing density adjusting method will be described with reference to a specific example.

A specific example will be described as a method for adjusting the density of a full-color printer using the TA system.
As described above, the density adjustment is performed for all the basic colors of the full-color printer. For the sake of explanation, the density adjustment of only one of the basic colors will be described.

First, the print image master is set on the scanner 4, and by the input operation of the input device 1, the processing unit A 23 obtains the density target values of 90% density and 30% density and stores them in the density target value storage unit 32. The user selects to perform the setting process, reads the print image master by the scanner reading unit 21, and stores it in the scanner reading storage unit 31. Then, the processing unit A23 causes the scanner reading storage unit 3
The average value of the entire 90% density and 30% density stored in 1 is obtained and set in the density target value storage unit 32.

The 90% density target value at this time is set to S9.
It is assumed that the density target values of 0 and 30% density are S30, and that S90 = 210 and S30 = 90.

Next, the adjustment print image actually printed by the TA system full-color printer 5 is set on the scanner 4, and the 90% stored in the density target value storage unit 32 is stored by the input operation of the input device. A density difference between the 90% density and the 30% density of the print image for adjustment is obtained with respect to the density target values of the density and the 30% density, the correction is performed, and the applied energy value changed by the correction is written to the full-color printer 5. The processing section B24, which is the processing, is selected and stored in the scanner reading storage section 31 by the scanner reading section 21.

Then, the processing unit B24 stores the 90% density and the 30% density stored in the scanner reading storage unit 31.
From the density value of the density, an average value for each dot of each dot of the printer head is obtained.

At this time, the average value of the 90% density portion of a certain dot of the printer head is S'90, and the average value of the 30% density portion is S'30. S'90 = 200, S'30 = 100 Suppose there was.

Then, the density difference between S'90 and S'30 with respect to the density target value stored in the density target value storage section 32 is obtained, and correction is made so as to eliminate the density difference.

That is, the formula shown in the above paragraph number 0038
, The applied energy at the full color development level is F,
Further, the applied energy value of the white level is represented as W, and
The applied energy value before the print density adjustment before the change is F ′,
It is assumed that W 'and the applied energy value after the print density adjustment after the change are F and W, and F' = 650 and W '= 150.

If the correction data value of the 90% density at this time is F'90 and the applied energy value of the 30% density is F'30, F'90 = (F'-W '). Times.0.9 + W' = (650−150) × 0.9 + 150 = 600 F′30 = (F′−W ′) × 0.3 + W ′ = (650−150) × 0.3 + 150 = 300

Thus, the applied energy value of 90% density with respect to the applied energy value after the print density adjustment is F90, 3
Assuming that the applied energy value of the 0% concentration is F30, F90 = F'90 × S90 ÷ S′90 = 600 × 210 ÷ 200 = 630 W30 = W′30 × S30 ÷ S′30 = 300 × 90 ÷ 100 = 270 Becomes

If the correction value required to increase the density by 10% is H10, then H10 = (F90-W30) × 10% {(90% -30%) = (630-270) × 10} ( 90-30) = 60.

As a result, when the applied energy values F and W after the print density adjustment after the change are obtained, F = F90 + H10 = 630 + 60 = 690 W = W30−H10 × 3 = 270−180 = 90 The applied energy values F = 690 and W = 90 are written in the TA full color printer 5 by the printer writing unit 25.

Accordingly, the TA system full-color printer 5 can print at a target density.

According to the above embodiment, the density of the entire surface of the density data, which is the image data obtained by reading the print image master having two density distributions of 90% and 30%, which are known and different, with the scanner 4 While the average value is calculated and used as the density target value, the density between each density of the adjustment image data read by the scanner 4 and the density target value calculated in advance is obtained. Since the difference is calculated and the applied energy value is corrected, color development of the same density is obtained between the full-color printers 5 which are printing devices, and the density difference between the devices can be prevented, and the color balance can be easily set at the best density. it can.

An average value for each dot of each dot of the printer head of the full-color printer 5 is calculated for each density of the image data for adjustment, and an average value of the calculated dot unit and the density target value are calculated. Since the density difference is calculated, it is possible to easily set a print having the best color balance without variation between apparatuses with a simple configuration.

Further, since the density of each of the basic colors is separately adjusted, printing can be performed with the best color balance.

Although the scanner 4 to be used is of the same type, a machine difference, that is, a difference between apparatuses usually occurs. However, by performing the above-described processing, it is necessary to obtain the density target value without taking the machine difference of the scanner 4 into consideration. Can be.

In the above embodiment, the configuration for adjusting the print density of the TA system full-color printer 5 has been described, but the same applies to any other printing apparatuses.

Next, another embodiment of the present invention will be described.

In the other embodiment, in the embodiment shown in FIGS. 1 and 2 described above, the print density is adjusted for each of the basic colors. Can also adjust the print density.

That is, assuming that the three basic colors are yellow, magenta, and cyan, in the embodiment shown in FIGS. 1 and 2, three operations are performed for the three colors of yellow, magenta, and cyan. Although it is necessary to perform the print density adjustment using the print images of 90% density and 30% density of gray, it can be performed at one time.

The gray 90% density is a mixture of three colors of 90% density of yellow, 90% density of magenta and 90% density of cyan, and 30% density of gray is 30% density of yellow. It is a mixture of density, 30% density of magenta color and 30% density of cyan color.

That is, gray 90% density and 30%
By reading the density with the scanner 4, the values of 90% density and 30% density of each color of yellow, magenta and cyan can be checked at a time.

When actually adjusting the target density of the yellow color, only the 90% density and the 30% density of the yellow color are extracted from the gray 90% density and the 30% density, and the yellow F and W are applied. It suffices to change the energy value. Further, the printing density can be adjusted similarly for magenta and cyan colors.

[0064]

According to the present invention, the density average value of the entire surface of the image data of the image having two density distributions whose densities are known in advance is calculated and used as the density target value, while the image data is printed. The density difference between each density of the obtained adjustment image data and the density target value calculated in advance is calculated to correct the applied energy value, so that the same color development is obtained between the printing apparatuses, and the density difference between the apparatuses is obtained. Can be prevented, and the color balance can be easily set at the best density.

An average value for each dot of each dot of the printer head of the printing apparatus is calculated for each density of the adjustment image data, and a density difference between the calculated average value of the dot unit and the density target value is calculated. Is calculated, it is possible to easily set a print having the best color balance without variation between apparatuses with a simple configuration.

Further, since the density of each of the basic colors is separately adjusted, printing can be performed with the best color balance.

Further, it is possible to easily obtain the density target value without taking into account the machine difference in inputting an image.

Since the image data obtained by inputting an image of a gray-colored image composed of the basic colors is used, good printing can be performed without variation without adjusting the print density for each of the plurality of basic colors. Can be easily obtained.

[Brief reading of drawings]

FIG. 1 is a block diagram of a print density adjusting apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating an operation of print density adjustment according to the first embodiment.

[Explanation of symbols]

 Reference Signs List 1 input device 2 density adjustment tool 3 storage memory as storage unit 4 scanner 5 TA full car printer as printing device 21 scanner reading unit as reading unit 22 discriminating unit 23 processing unit A as target value calculation processing unit 24 Processing part B as density difference calculation processing part 25 Printer writing part 31 Scanner reading storage part 32 Density target value storage part

Claims (7)

(57) [Claims] 1. A print density adjusting method for adjusting the print density of the printer, the previously said average density value of the entire surface at each concentration of the image data of the image having a different density distribution reflecting the image entered at a known concentration The image data is printed together with the calculated density target value, and the printed image data is again input as an image. The density difference between each density of the adjustment image data obtained and the corresponding known density of the image data A print density adjustment method for correcting an applied energy value when printing based on the density difference.
Indicates the printing device's printer for each density of the adjustment image data.
The average value of each dot in all dots of the head
Calculated and the density of the calculated average value in dot units and the density target value
A print density adjustment method comprising calculating a difference . 2. A plurality of basic colors of a printing apparatus.
The compensation of the applied energy value separately.
The method for adjusting print density according to claim 1 . 3. A plurality of different densities of which densities are known in advance.
Image with density distribution is the basic color for adjusting the density of the printing device
That the colors corresponding to
The print density adjusting method according to claim 1 or 2, wherein 4. A plurality of different densities of which densities are known in advance.
Images with a degree distribution are grayed with different densities
3. The method according to claim 1, wherein
Print density adjusting method according to. 5. A print density adjusting device for adjusting a print density of a printing device, wherein a reading unit stores image data obtained by inputting an image having a different density whose density is known in advance into a storage unit; A target value calculation processing unit for calculating an average density value of the entire surface at each density of the image data and storing the average value in the storage unit as a density target value; and an adjustment unit obtained by printing the image data and inputting the image again. A density difference calculation processing section for calculating a density difference between each density of the image data and a corresponding known density of the image data; and an applied energy for printing based on the density difference calculated by the density difference calculation processing section. A printer writing unit for correcting the value , wherein the density difference calculation processing unit
On the other hand, each one in all dots of the printer head of the printing apparatus
The average value of the dot unit is calculated, and the density between the calculated average value of the dot unit and the density target value is calculated.
A print density adjusting device for calculating a difference . 6. A reading section for adjusting the density of a printing apparatus.
If the color corresponding to the basic color differs at a
An image with a number density distribution is obtained by image input
A storage device that stores the image data stored in the storage unit.
Print density adjusting device according to Motomeko 5. 7. The reading section has a gray color in advance.
Images with multiple density distributions differing in known density
The image data obtained by the input to the storage unit
The print density adjusting device according to claim 5, wherein: