JP2004050610A - Image recorder and its adjusting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a practical low cost image recorder for recording an image by carrying a recording medium while performing scanning in the main scanning direction in which the image recorder can be calibrated while suppressing the effect of shading, and to provide a method for adjusting the image recorder. <P>SOLUTION: The image recorder 10 records the image of a test pattern for calibration at a recording position in the main scanning direction being set depending on the width of the recording medium in the main scanning direction using a recording unit 34, adjusts data obtained by measuring the density of the recorded image of the test pattern for calibration using adjustment data being set depending on the the recording position of the test pattern for calibration, and then calibrates an exposure unit 34 using the adjusted density measurement data and target density data. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image recording apparatus that records an image while transporting a recording medium while scanning in the main scanning direction, and an adjustment method for the image recording apparatus, and more particularly, to perform appropriate calibration (calibration) stably. The present invention relates to an image recording apparatus capable of stably outputting an appropriate image corresponding to a desired input image, and a method for adjusting the image recording apparatus.
[0002]
[Prior art]
In various image recording apparatuses such as a laser printer and a copying apparatus, when an image is recorded while transporting a recording medium while scanning a light beam or the like in the main scanning direction, an appropriate image is displayed according to the supplied input image signal. The image recording apparatus is calibrated so that recording can be performed, and an appropriate output image signal is output.
[0003]
Calibration performed on the image recording apparatus is performed, for example, according to the following method.
First, a test chart for calibration is created by recording patches of the three primary colors of cyan, magenta, and yellow in a predetermined format in a line with different densities.
Next, the density of the patch of the recorded calibration test chart is measured.
Thereafter, the image recording apparatus is calibrated using density measurement data obtained by density measurement and density data (target density data) of a target patch. For example, the conversion condition for converting the input image signal of the image into the output image signal and the conversion condition for converting the intermediate signal (for example, logarithmic exposure amount signal) of the image into the output image signal are calibrated.
[0004]
[Problems to be solved by the invention]
However, in the above calibration, even if it is confirmed that the calibration test chart is properly output, a desired image may not be output due to the influence of shading of the image recording apparatus.
Specifically, since the calibration test chart is recorded at a predetermined position on the recording medium, even if a target density is obtained in each patch of the calibration test chart, a part other than the predetermined position, for example, In other words, an appropriate image cannot be obtained near the center position of the image. In particular, when the image densities of the three primary colors cyan, magenta, and yellow are not uniform on the image, there arises a problem that the color of the recorded image varies depending on the position of the image.
[0005]
Note that shading refers to a state in which the density or color of a recorded image does not become uniform on the image but becomes non-uniform, thereby forming density unevenness. For example, after imagewise exposure is performed on a photothermographic material (donor film) using an exposure optical system, an image forming solvent such as water is applied to the photothermographic material, and an image receiving layer ( In an image exposure apparatus that heats and develops an image receiving material (receiver) having a dye fixing layer), shading occurs due to the locality of the transmittance or reflectance of the optical member in the exposure optical system, or water or the like Shading occurs due to temperature unevenness in thermal development when an image forming solvent is applied and thermal development is performed. In particular, image density unevenness is likely to occur in the main scanning direction, and a difference between colors such as cyan, magenta, and yellow is reflected in the color and easily causes a visual problem.
[0006]
In order to solve such a problem, Japanese Patent Laid-Open No. 2001-268363 discloses a gradation pattern (calibration test chart) that is point-symmetrically recorded with respect to the center point of the recording medium, and the point-symmetric gradation pattern is read. An image forming apparatus for obtaining an average value of density data is proposed. Thereby, a density correction table can be generated in consideration of the density difference due to the difference in image recording position.
However, in this case, it is necessary to perform density measurement by two-dimensional scanning in reading the gradation pattern. For this reason, incorporating the two-dimensional scanning mechanism into the image forming apparatus has a problem that the apparatus configuration becomes complicated and the cost of the apparatus increases. Further, the shading pattern (pattern such as density unevenness) is not necessarily point-symmetric but may be non-linear. In the case of non-linearity, for example, there is a problem that an important part of an image is not necessarily an appropriate image.
Further, in order to correct the shading itself, a method of recording an image with correction for each recording position on the recording medium is also conceivable. However, in this case, it is necessary to perform high-speed computation for correcting shading for each recording position, and there is a problem that the cost of the apparatus increases.
[0007]
Therefore, in order to solve the above-described problems of the prior art, the present invention suppresses the influence of shading in an image recording apparatus that records an image by transporting a recording medium while performing scanning in the main scanning direction. An object of the present invention is to provide a practical image recording apparatus which can calibrate the apparatus and which is inexpensive, and a method for adjusting the image recording apparatus.
[0008]
[Means for Solving the Problems]
Therefore, the present invention is an image recording apparatus that records an image by performing scanning in the main scanning direction while conveying a recording medium,
Recording means for recording an image of the calibration test pattern at a recording position in the main scanning direction set in accordance with the width of the recording medium in the main scanning direction;
Adjustment means for adjusting density measurement data obtained by measuring the density of the recorded calibration test pattern image using adjustment data set according to the recording position of the calibration test pattern;
There is provided an image recording apparatus comprising calibration means for calibrating the recording means using adjusted density measurement data and target density data of an image of the calibration test pattern.
[0009]
Here, the adjustment data is preferably default data preset in advance for each width of the recording medium in the main scanning direction. Alternatively, the adjustment data is preferably data obtained by correcting default data preset in advance for each width of the recording medium in the main scanning direction.
[0010]
The present invention is also an adjustment method for an image recording apparatus having an image recording means for recording an image by performing scanning in the main scanning direction while conveying a recording medium,
An image of the test pattern for calibration is recorded at a recording position in the main scanning direction set according to the width of the recording medium in the main scanning direction,
Density measurement data obtained by measuring the density of the recorded calibration test pattern is adjusted using adjustment data set according to the recording position of the calibration test pattern,
An adjustment method for an image recording apparatus is provided, wherein the recording means is calibrated using adjusted density measurement data and target density data of an image of the calibration test pattern.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The image recording apparatus of the present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings.
FIG. 1 is a block diagram conceptually showing an image recording apparatus (hereinafter referred to as a recording apparatus) 10 which is an embodiment of the image recording apparatus of the present invention.
The recording apparatus 10 is an apparatus that records a photosensitive heat-developable recording material as a recording medium, and uses this recording medium to transfer and form an image on the image receiving material in the presence of an image forming solvent such as water.
The image recording apparatus of the present invention is not limited to those using a photosensitive heat-developable recording material, and may use various photosensitive materials such as negative and reversal films and silver salt photographic photosensitive materials such as photographic paper. Further, an electrophotographic photosensitive member or an electrophotographic photosensitive material may be used.
[0012]
The recording apparatus 10 includes a recording material supply unit 12 that supplies a photosensitive heat-developable recording material A (hereinafter referred to as recording material A), an exposure unit 14, an image receiving material supply unit 16 that supplies an image receiving material R, water The coating unit 18, the heat development transfer unit 20, the waste material storage unit 22, and the concentration measurement unit 26 using the densitometer 24 are configured. The exposure unit 14 includes recording means, adjustment means, and calibration means in the present invention.
[0013]
Also, on the upper surface of the recording apparatus 10, various operation instructions such as image recording start, (hard copy) output sheet number setting, recording material A type and size (width), color / density adjustment, enlargement / reduction magnification, etc. The operation panel 23 can be input. The operation panel 23 is also a means for correcting adjustment data for adjusting density measurement data of each patch of a calibration test chart (calibration test pattern) described later.
The operation panel 23 is basically the same as a known color image recording apparatus. For example, color keys for selecting each color of cyan, magenta, and yellow, increase / decrease keys such as a plus key and a minus key, a numeric keypad, Start key, operation keys for inputting various operation instructions such as execution of calibration and input of adjustment data, display panel for displaying input instructions and operations, arrow keys for selecting options displayed on the display panel, etc. Etc.
[0014]
In FIG. 1, the recording material A is stored in a light-shielding magazine 28 and loaded into the recording apparatus 10 while being wound in a roll shape in a long state (with the photosensitive surface facing inward).
A drawer roller pair 30 and a cutter 32 are arranged in the vicinity of the outlet of the recording material A of the magazine 28. The recording material A is drawn out by the drawing roller pair 30 by a length corresponding to the print to be created, cut by the cutter 32, and then transported to the exposure unit 14 downstream (downstream in the material transport direction) for exposure. Is done.
[0015]
The exposure unit 14 includes an exposure unit 34 and a sub-scanning conveying unit.
The exposure unit 34 includes three types of light beam light sources (R light source, G light source, B light source) and light corresponding to exposure of the red (R), green (G) and blue (B) photosensitive layers of the recording material A. A deflector, an fθ lens, and the like are provided, and a light beam c modulated according to a recorded image is deflected in the main scanning direction (perpendicular to the paper surface in FIG. 1) and exposed at a predetermined exposure position in the transport direction. This is a known light beam scanning optical system. On the other hand, the sub-scanning conveying means is also well-known, and in the illustrated example, it is arranged with the exposure position in the conveying direction (upward in the drawing in FIG. 1), and the recording material A is orthogonal to the main scanning direction. It is composed of a pair of transport rollers 38 and 38 that transport in the sub-scanning direction. In the exposure unit 34, an image is recorded on the recording material A by aligning the center position of the recording material A in the main scanning direction with the center position of the exposure unit 34 in the main scanning direction.
The recording material A supplied from the recording material supply unit 12 is modulated in accordance with the image to be recorded and deflected in the main scanning direction while being conveyed in the sub scanning direction by the conveying roller pair 38 of the sub scanning conveying unit 36. By scanning with the beam c, two-dimensional scanning exposure is performed, and a latent image is recorded and conveyed downstream.
[0016]
FIG. 2A is a block diagram showing an outline of the exposure control system of each light beam light source of the exposure unit 34.
In the illustrated example, an input image signal supplied from an image signal supply source F such as an image pickup unit such as a scanner (image reading device) or a digital camera or an image processing device is a modulation signal as an output image signal by a signal conversion unit 40. After being converted to (MQ), it is supplied to the driver 42. The driver 42 modulates and drives each light beam light source according to the modulation signal.
Here, the signal conversion unit 40 converts a PS-PDLUT (lookup table) from the input image signal (PS) into a logarithmic exposure signal (PD) representing a logarithmic value of the exposure amount to the recording material A as an intermediate signal. 40a and a calibration LUT (look-up table) 40b for converting the logarithmic exposure amount signal into a modulation signal (MQ) input to the driver 42.
[0017]
The PS-PDLUT 40a associates an input image signal with a logarithmic exposure amount over a range of values that the input image signal can take (0 to 255 for an 8-bit signal). Is set to
On the other hand, the calibration LUT 40b is an LUT for absorbing fluctuations in the color density characteristics indicating the relationship between the logarithmic exposure amount of the recording material A and the image density and fluctuations in the characteristics of the driver 42. Calibration in the present invention refers to changing the calibration LUT 40b and is changed so that each patch of a calibration test chart (hereinafter referred to as a test chart) recorded on the recording material A has a target density. .
[0018]
In the exposure unit 34, a calibration calculation unit 46 is connected to the signal conversion unit 40.
The calibration calculation unit 46 modulates the test chart density measurement data sent from the densitometer 24, the target density data representing the target density value of each patch, and the logarithmic exposure amount signal from the log exposure signal at the time of calibration. The signal converter 40 uses the LUT data of the calibration LUT 40b that is currently set to be converted, the test chart data (hereinafter referred to as test chart data), and the adjustment data of the density measurement data to generate a log exposure signal. This is a part for calculating a conversion condition for converting the signal into a modulation signal and rewriting the LUT of the calibration LUT 40b based on the calculated conversion condition.
[0019]
The calibration calculation unit 46 includes a density measurement data adjustment unit 46a, a calculation unit 46b, an adjustment data holding unit 46c, an LUT data holding unit 46d, and a test chart data holding unit 46e.
In the test chart data holding unit 46e, test chart data is recorded and held as a logarithmic exposure amount signal. When the test chart is recorded on the recording material A, the test chart data held in the test chart data holding unit 46e is: An image memory (not shown) expands to an address corresponding to a recording position determined for each size of the recording material A, and the expanded test chart data is supplied to the calibration LUT 40b and converted into a modulation signal. To be supplied.
[0020]
Here, the test chart recorded using the test chart data is, for example, in a direction (conveying direction) in which patches of three primary colors (for example, cyan, magenta, and yellow) having different densities in stages are orthogonal to the main scanning direction. It is a known test chart formed in a line in order (see FIGS. 3A and 3B). As described above, the test chart data recorded and held in the test chart data holding unit 46e is expanded to an address in the image memory corresponding to the recording position determined for each size of the recording material A, and the test chart is recorded. Therefore, the recording position in the main scanning direction in the recording material A of the test chart is determined and recorded according to the size of the recording material A.
This is because, as will be described later, when density measurement is performed by the densitometer 24, it corresponds to the reading position of the patch on the image receiving material R by the densitometer 24. That is, the image receiving material R on which the test chart is transferred from the recording material A is conveyed in a state where the edge end is abutted against a guide (not shown) of the densitometer 24, and is read at a predetermined distance from the edge end. This is because the density of each patch of the test chart passing through the position can be measured.
Thus, an image of the test chart is recorded at a predetermined position (recording position) on the recording material A according to the size of the recording material A.
The density measurement data adjustment unit 46a, the calculation unit 46b, the adjustment data holding unit 46c, and the LUT data holding unit 46d in the calibration calculation unit 46 will be described in detail later.
[0021]
In the recording apparatus 10, the signal conversion unit 40 may directly convert the input image signal into a modulation signal that is an output image signal without using a logarithmic exposure amount signal that is an intermediate signal.
[0022]
The recording material A on which the latent image is recorded in the exposure unit 14 is conveyed by the three conveyance roller pairs 48, water as an image forming solvent is applied in the water application unit 18, and further conveyed to the resist unit 50. .
[0023]
On the other hand, the image receiving material R is obtained by applying a dye fixing material on the image receiving surface, and is wound in a roll shape in an elongated state (with the image receiving surface inside) in the image receiving material supply unit 16. It is stored in the magazine 52 and loaded into the recording apparatus 10.
A drawer roller pair 54 and a cutter 56 are arranged in the vicinity of the take-out port of the magazine 52. The image receiving material R is drawn out by the drawing roller pair 54 by a length corresponding to the print to be created, cut by the cutter 56, conveyed by the three conveying roller pairs 58, and supplied to the registration roller pair 60. Note that the image receiving material R is cut slightly longer than the recording material A in order to facilitate peeling from the recording material A by a peeling claw 68 described later.
[0024]
Both the registration unit 50 and the registration roller 60 convey the recording material A and the image receiving material R at the same timing, so that they are superimposed and conveyed to the heat development transfer unit 20.
[0025]
The heat development transfer unit 20 includes belt conveyors 62 and 64 including endless belts and rollers, and a heater 66 disposed so as to be included in the belt conveyor 62 (its endless belt).
The two belt conveyors 62 and 64 sandwich and convey the laminate of the recording material A and the image receiving material R by the endless belts. During the nipping and conveying, the laminated body is heated by the heater 66 to visualize the latent image formed on the recording material A, and this image is further transferred to the image receiving material R.
[0026]
A peeling claw 68 is disposed downstream of the heat development transfer unit 62.
When the leading end of the laminate of the recording material A and the image receiving material R that has been subjected to heat development and image transfer in the heat development transfer unit 62 reaches the peeling claw 68, the peeling claw 68 is activated to enter between the two materials. , Peel off both.
[0027]
The recording material A peeled from the image receiving material R by the peeling claw 68 is sent to the waste material container 22 by the conveying roller pair 70.
The waste material container 22 includes a driving means including a drum 72, an endless belt 74 wound around the drum 72 (the outermost layer of the recording material A), and rollers 76, 76. The used recording material A is wound around the drum 72 and discarded when it reaches a predetermined amount.
[0028]
On the other hand, the image receiving material R from which the recording material A has been peeled is conveyed by a pair of conveying rollers 78, 78... And further discharged by the discharge roller 80 to the tray 82 as a hard copy on which an image is recorded.
[0029]
The density measuring unit 26 is disposed between the most downstream conveying roller pair 78 and the discharge roller 80.
The density measuring unit 26 measures the density of the test chart recorded on the image receiving material R when the recording apparatus 10 is calibrated, and sends the density measurement data to the calibration calculation unit 46 of the exposure unit 34. The densitometer 24 and the white reference plate 84 are included.
[0030]
The densitometer 24 is a known one-dimensional densitometer that measures the density of each patch of a recorded test chart by irradiating the image receiving material R conveyed in one direction with light and measuring the reflected light. It is.
As an example, an R light source that emits R light corresponding to the density measurement of the C (cyan) patch of the test chart recorded on the image receiving material R, and a G light that corresponds to the density measurement of the M (magenta) patch are emitted. A G light source that emits light, a B light source that emits B light corresponding to the density measurement of the Y (yellow) patch, a driver that drives the light source, a controller that controls the lighting of each light source by controlling the driver, and an image reception A sensor that measures the amount of reflected light from the material R and the white reference plate 84, and a signal processing unit that processes the output signal of the sensor and sends it as a density value (density measurement data) to the calibration calculation unit 46. Composed. When the density measurement unit 26 performs density measurement, the image receiving material R, on which the test chart has been transferred from the recording material A, is conveyed with the edge end abutting against a guide (not shown) of the density meter 24, and from the edge end, a predetermined amount is conveyed. The density of each patch of the test chart passing through the reading position provided at a distance of is measured.
As such a concentration measuring unit 26, a concentration measuring device disclosed in Japanese Patent Laid-Open No. 2001-324387 is used as an example.
[0031]
At the time of calibration, the test chart data held in the test chart data holding unit 46e is developed at an address corresponding to the recording position determined for each size of the recording material A in an image memory (not shown). The developed test chart data is supplied to the calibration LUT 40b, converted into a modulation signal, and then supplied to the driver 42.
In response to this, a test chart is exposed and recorded on the recording material A, is thermally developed in the thermal development transfer unit 20, and is transferred to the image receiving material R. When the image receiving material R on which the test chart is recorded by the transfer passes through the density measuring unit 26, each patch of the test chart is read by the densitometer 24, and the density measurement is performed. Thereafter, the data is output to the tray 82.
The image receiving material R output to the tray 82 may be set in a predetermined test chart supply unit, and the density measurement may be performed by the densitometer 24. In this case, the instruction to start density measurement is not limited to the operator giving an instruction to start density measurement. For example, when the image receiving material R is set at a predetermined position, it is automatically read (after a predetermined time has elapsed). The operation for may be started.
[0032]
In the density measurement, the image receiving material R is transported in a state where the edge end is abutted against a guide (not shown). 24.
Specifically, each of the R, G, and B light sources is sequentially turned on, the amount of reflected light from the white reference plate 84 is measured, the reference amount of light is measured, and then the test recorded on the image receiving material R The density of each patch in the chart is measured, and the density measurement data is sent to the calibration calculation unit 46 of the exposure unit 34.
[0033]
As described above, the calibration calculation unit 46 includes the density measurement data adjustment unit 46a, the calculation unit 46b, the adjustment data holding unit 46c, the LUT data holding unit 46d, and the test chart data holding unit 46e. Then, the LUT of the calibration LUT 40b is rewritten according to the calculated conversion condition.
Here, the data holding unit 46c records and holds adjustment data for adjusting the density measurement data supplied from the densitometer 24. The adjustment data is stored for each size of the recording material A as shown in FIG. Records are kept. Here, the adjustment data is data for adjusting density measurement data of each patch. For example, the test chart includes 6 patches of cyan (C), 6 patches of magenta (M), yellow ( In the case where six patches of Y) are recorded with different densities, the adjustment data has a total of 18 values for each patch.
The adjustment data is provided as an adjustment amount for the target density value of each patch. The adjustment data is set according to the size of the recording material A, but the recording position in the main scanning direction of the test chart in the recording material A is determined according to the size of the recording material A. Therefore, it can be said that the adjustment data is set according to the recording position of the test chart in the recording material A in the main scanning direction.
[0034]
FIG. 2B shows an example of adjustment data recorded and held in the data holding unit 46c according to the size of the recording material A. In this example, the size (width in the main scanning direction) of the recording material A is 127 mm and 297 mm. In the case of 297 mm, the adjustment data Data2 and Data2 ′ are recorded and held in the data holding unit 46c. . As will be described later, the recording apparatus 10 can set which position of the recording material A is used as a reference, and the two adjustment data of Data2 and Data2 ′ are selected according to this setting. Adjustment data. This selection may be made by an operator's instruction input from the operation panel 23, or one adjustment data may be preferentially selected in advance.
Of course, the number of adjustment data is not limited to two and may be two or more.
The adjustment data may be preset by the operator for each size of the recording material A using the operation panel 23, or may be incorporated at the time of manufacturing the image recording apparatus and preset in advance. Good.
Further, the adjustment data can be corrected by an instruction from the operation panel 23 at the time of calibration. For example, when the calibration is not properly performed due to a change with time of the recording apparatus 10 or a change in the color development characteristic of the recording material A, the calibration is appropriately performed by correcting the adjustment data set in advance as a default. Can do.
[0035]
The LUT data holding unit 46d records and holds PS-PDLUT data and calibration LUT data set according to the type of the recording material A, and further, target density data representing the target density of each patch in the test chart. Keep record.
In the LUT data holding unit 46d, the calibration LUT data set in the calibration LUT 40b is recorded and held when the image recording apparatus 10 is lowered, and according to the type of the recording material A when the image recording apparatus 10 is started. The PS-PDLUT data is called and supplied to the PS-PDLUT 40a, and the calibration LUT data recorded and held at the time of the fall is called and supplied to the calibration LUT 40b. Further, when the conversion condition is calculated in the calculation unit 46b, the PS-PDLUT data currently set in the PS-PDLUT 40a, the calibration LUT data set in the calibration LUT 40b, and the target density data are calculated. To the unit 46b.
[0036]
The density measurement data adjustment unit 46a calculates an adjustment amount in the value of the density measurement data from the adjustment data provided for the target density value of each patch, and the adjustment calculated from the value of the density measurement data. This is a part for obtaining the value of the adjusted concentration measurement data by subtracting the amount. A value of the adjusted density measurement data is obtained for each patch whose density is measured.
The calculation unit 46b calls the PS-PDLUT data set according to the type of the recording material A, the calibration LUT data currently set in the calibration LUT 40b, and the target density data, and these are called. Using the data and the density measurement data adjusted by the density measurement data adjustment unit 46a, a conversion condition from the logarithmic exposure amount to the modulation signal is calculated, and the LUT of the calculated conversion condition is supplied to the calibration LUT 40b. It is a part to be rewritten.
The calculation method of the conversion condition in the calculation unit 46b is not particularly limited in the present invention as long as calibration is performed using the adjusted density measurement data and the target density data representing the target density of the test chart image. The calibration method disclosed in Japanese Patent No. 241913 can be suitably used.
[0037]
Specifically, using the adjusted density measurement data value and the log exposure signal value at the time of test chart recording, a log exposure value corresponding to the target density data targeted for each patch is obtained by interpolation, On the other hand, a target log exposure value corresponding to target target density data in each patch is obtained using characteristic data between the log exposure and color density. Thereafter, a conversion condition for converting the log exposure signal into the modulation signal is calculated using the log exposure value obtained by the interpolation and the target exposure value.
[0038]
As described above, the recording apparatus 10 adjusts the density measurement data obtained by measuring with the densitometer 24 using the adjustment data set according to the size of the recording material A. As described above, the density measurement data is adjusted using the adjustment data set according to the size of the recording material A for the following reason.
[0039]
That is, when recording on the recording material A, the center position of the recording material A is aligned with the center position in the scanning direction by the light beam c, and when the scanned light beam c is at a predetermined scanning position, the recording material A is recorded. A test chart is recorded and recorded at a predetermined position (recording position) on the recording material A. For example, as shown in FIG. 3A, when the size of the recording material A is 127 mm, the distance w from the center position in the scanning direction. ₁ By recording the test chart at a distance, the distance w from the center position (CL) of the recording material A ₁ A test chart is recorded at a remote location. On the other hand, as shown in FIG. 3B, when the size of the recording material A is 297 mm, the distance w from the center position in the scanning direction. ₂ By recording the test chart at a distance, the distance w from the center position (CL) of the recording material A ₂ A test chart is recorded at a remote location. Thereby, the edge E of the recording material A regardless of the size of the recording material A. ₁ Same distance from ₀ A test chart is recorded at a remote location. Thus, the image receiving material R transferred from the recording material A to the test chart is the edge E of the recording material A. ₁ Is transported in a state where the edge end corresponding to the abutting against the guide of the densitometer 24, and the distance w from the edge end of the image receiving material R is ₀ Edge E at a remote location ₂ The density of each patch is measured from the edge of the image receiving material R corresponding to.
[0040]
Thus, the edge E of the recording material A regardless of the size of the recording material A ₁ Distance from ₀ Since the test chart is recorded at a distant position, the scanning position for recording the test chart differs depending on the size of the recording material A when viewed from the center position in the main scanning direction. Therefore, if there is shading when recording is performed by scanning the light beam c in the scanning direction, the density of each patch of the test chart also changes depending on the recording position. FIG. 4 shows an example of image density distribution of cyan (C), magenta (M), and yellow (Y) as an example of shading.
When calibration is performed in a state where the above-mentioned image density distribution characteristics exist (in a state where shading occurs), the test chart recording position can be obtained even if the density of each patch of the test chart can reproduce the target density. For example, in the vicinity of the center position, a color different from the color at the recording position of the test chart occurs. In the case of the example shown in FIG. 4, the distance w from the center position (CL). ₂ When calibration is performed by a conventional method using a test chart recorded at a distant position, the distance w from the center position ₂ Since the image density is lower in the order of cyan and further yellow compared with the image density at the center position (CL) at the distant position, an image having a strong magenta to blue color is recorded near the center position. .
[0041]
The recording apparatus 10 adjusts the density measurement data using the adjustment data so that such a color does not occur. For example, in the example shown in FIG. 4, the difference between the image density at the center position and the image density at the recording position where the test chart is recorded is used as the adjustment data. Thus, calibration can be performed using density measurement data adjusted with the center position as a reference.
As shown in FIG. 2B, the recording apparatus 10 records and holds a plurality of adjustment data for one recording material A size. You can choose. As a result, a reference position for calibration can be set.
[0042]
The adjustment data is given in advance by default setting, but may be set by the operator inputting adjustment data on the operation panel 23 from the image density data information as shown in FIG. Good. For example, as shown in FIG. 5, a test chart corresponding to a size of 127 mm and a test chart corresponding to a size of 297 mm are recorded on the same recording material A to obtain density measurement data of each patch. A difference may be obtained and adjustment data may be set from this difference. The density measurement data may be obtained when the recording apparatus 10 is manufactured or the exposure unit 34 is replaced, and adjustment data may be recorded and held in the data holding unit 46c as a default setting. In the example of FIG. 5, the test chart is recorded at two positions. However, a test chart recorded at a plurality of positions (two or more positions) can be used.
[0043]
Further, as shown in FIG. 6, the recording of the test chart may be changed as in levels 1 to 3 in accordance with the accuracy level at the time of calibration.
Level 1 is used when calibration accuracy is not required, and a test chart is created with the arrangement direction of patches in the test chart as the main scanning direction. In this case, the calculation unit 46b directly calculates the conversion condition between the logarithmic exposure signal and the modulation signal without adjusting the density measurement data using the adjustment data described above. In level 1, since the arrangement direction of the patches in the test chart is the main scanning direction, the length of the recording material A in the direction (conveying direction) orthogonal to the main scanning direction can be shortened, and the usage amount of the recording material A Can be saved.
At level 2, as described above, the test chart is recorded at the scanning position set in accordance with the size of the recording material A, and the edge edge E is recorded. ₁ Distance from ₀ A test chart is recorded at a distant position, and the density of each patch on the test chart is measured. Further, the concentration measurement data of the test chart is adjusted using the adjustment data, and the conversion condition is calculated as described above using the adjustment result.
At level 3, a test chart is recorded near the center position of the recording material A, and the distance w from the recording position of the test chart is recorded. ₀ A cutoff line L is recorded at a remote position. Accordingly, the image receiving material R to which the test chart and the cut line L are transferred is cut from the cut line L, and the edge of the image receiving material R along the cut line L is abutted against the guide of the densitometer 24 to measure the density of the test chart. it can. The density measurement data obtained by the density measurement is adjusted using adjustment data set according to the recording position of the test chart in the recording material A. This makes it possible to perform highly accurate calibration near the center position without being affected by shading.
[0044]
As described above, in the recording apparatus 10, the adjustment data is set according to the size of the recording material A, or the adjustment data is set according to the recording position of the test chart in the recording material A, and further adjusted by the operation panel. Since the data can be corrected, the desired calibration can be performed. In addition, the adjustment parameter can be selected from a plurality of adjustment parameters and the adjustment parameter can be corrected. It can be performed. It is also possible to use a densitometer that does not cost one dimension.
[0045]
The image recording apparatus of the present invention and the adjustment method of the image recording apparatus have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. Of course, changes may be made.
[0046]
【The invention's effect】
As described above in detail, the image recording apparatus of the present invention performs scanning in the main scanning direction while transporting the recording medium, and records an image of the test pattern for calibration at a predetermined scanning position. Since the density measurement data obtained by measuring the density of the calibration test pattern image is adjusted using the adjustment data set in accordance with the scanning position, the recording position of the calibration test pattern on the recording medium is adjusted. Furthermore, it is possible to perform calibration based on a desired position that is not affected by the width (size) of the recording medium in the main scanning direction. As a result, the influence of shading existing in the image recording apparatus can be suppressed in a desired region.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an example of an image recording apparatus of the present invention.
2A is a diagram showing a configuration of the exposure unit shown in FIG. 1, and FIG. 2B is a diagram for explaining an example of adjustment data held in the exposure unit.
FIGS. 3A and 3B are diagrams showing examples of test chart patterns recorded by the image recording apparatus of the present invention. FIGS.
FIG. 4 is a diagram illustrating shading that occurs in the image exposure apparatus.
FIG. 5 is a diagram showing another example of a test chart pattern recorded by the image recording apparatus of the present invention.
FIG. 6 is a diagram showing another example of a test chart pattern recorded by the image recording apparatus of the present invention.
[Explanation of symbols]
10 Image recording device
12 Recording material supply section
14 Exposure section
16 Image receiving material supply section
18 Water application part
20 Thermal development transfer section
22 Waste material container
23 Operation panel
24 Densitometer
26 Concentration measurement unit
34 Exposure unit
40 Signal converter
42 drivers
46 Calibration calculator
46a Density measurement data adjustment unit
46b arithmetic unit
46c Adjustment data holding unit
46d LUT data holding unit
46e Test chart data holding unit
84 White reference plate

Claims (4)

An image recording apparatus for recording an image by performing scanning in the main scanning direction while conveying a recording medium,
Recording means for recording an image of the calibration test pattern at a recording position in the main scanning direction set in accordance with the width of the recording medium in the main scanning direction;
Adjustment means for adjusting density measurement data obtained by measuring the density of the recorded calibration test pattern image using adjustment data set according to the recording position of the calibration test pattern;
An image recording apparatus comprising: calibration means for calibrating the recording means using adjusted density measurement data and target density data of an image of the calibration test pattern. The image recording apparatus according to claim 1, wherein the adjustment data is default data preset in advance for each width of the recording medium in the main scanning direction. The image recording apparatus according to claim 1, wherein the adjustment data is data obtained by correcting default data preset in advance for each width of the recording medium in the main scanning direction. An adjustment method of an image recording apparatus having image recording means for recording an image by performing scanning in the main scanning direction while conveying a recording medium,
An image of the test pattern for calibration is recorded at a recording position in the main scanning direction set according to the width of the recording medium in the main scanning direction,
Density measurement data obtained by measuring the density of the recorded calibration test pattern is adjusted using adjustment data set according to the recording position of the calibration test pattern,
An adjustment method for an image recording apparatus, wherein the recording means is calibrated using adjusted density measurement data and target density data of an image of the calibration test pattern.

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