An image forming apparatus may form an image on a recording medium, such as paper, through an image forming process of charging, exposing, developing, transferring, and fusing. For example, an image forming apparatus may form a visible toner image on a photoconductor by supplying toner to an electrostatic latent image formed on a photoconductor, transfer the toner image to a recording medium, and fuse the transferred toner image on the recording medium to print the image on the recording medium.
Various examples will be described with reference to the accompanying drawings. The examples described below may be modified and implemented in various different forms. Like reference numerals in the drawings denote like elements, and thus a repetitive description may be omitted.
An “image forming apparatus” may include any type of apparatus capable of performing an image forming job, such as a printer, a copier, a scanner, a fax machine, a multi-function printer (MFP), a display apparatus, or the like.
Referring to
The plurality of developing devices 10 may form toner images having a cyan color C, a magenta color M, a yellow color Y, and a black color K. The plurality of developing agent cartridges 20 may respectively accommodate developing agents having the cyan, magenta, yellow, and black colors C, M, Y, and K to be supplied to the plurality of developing devices 10. The developing agent supply unit 30 may supply a developing agent to the developing device 10 through a supply pipe 40.
The developing device 10 may include a photoconductor 14, on a surface of which an electrostatic latent image is formed, and a developing roller 13 to supply the developing agent to the electrostatic latent image via a developing bias voltage to develop a visible toner image. A photosensitive drum may be an example of the photoconductor 14, on the surface of which the electrostatic latent image is formed, and may include an organic photoconductor (OPC) including a conductive metal pipe and a photosensitive layer formed on an outer circumferential surface of the conductive metal pipe. A charging roller 15 may be an example of a charger to charge the photoconductor 14 to have a uniform surface potential.
The developing device 10 may further include a charging roller cleaner (not shown) to remove a developing agent or a foreign material, such as dust, etc., attached to the charging roller 15, a cleaning member 17 to remove the developing agent remaining on a surface of the photoconductor 14 after an intermediate transfer process, and a regulation member to regulate the amount of the developing agent supplied to a developing area facing the photoconductor 14 and the developing roller 13. A waste developing agent may be accommodated in a waste developing agent container 17a.
The exposure unit 50 may form an electrostatic latent image on the photoconductor 14 by irradiating light, modulated in correspondence to image information, onto the photoconductor 14, and may include a laser scanning unit (LSU) using a laser diode as a light source, a light-emitting diode (LED) exposure unit using an LED as a light source, or the like.
The transfer unit may transfer the toner image formed on the photoconductor 14 to a recording medium P. For example, the transfer unit may include an intermediate transfer medium 60, an intermediate transfer roller 61, and a transfer roller 70.
Developed toner images may be sequentially and intermediately transferred to the intermediate transfer medium 60. The recording medium P loaded in a source paper unit 90 that is coupled to a body 1 of the image forming apparatus 100 may be transported along a source paper path 91 to a location between the transfer roller 70 and the intermediate transfer medium 60. The toner image intermediately transferred onto the intermediate transfer medium 60 may be transferred to the recording medium P by a transfer bias voltage applied to the transfer roller 70. When the recording medium P passes through the fusing unit 80, the toner image may be fused to the recording medium P due to heat and pressure. The recording medium P on which the fusing is completed may be discharged through a discharge roller 92.
Referring to
For example, the image forming apparatus 100 may calculate the amount of change of a start position of a valid image area with respect to the certain color in the main scanning direction against the reference color, and the amount of change of a width of the valid image area, based on the change in the detection time at which the beam is detected in the main scanning direction. Here, the start position of the valid image area may be indicated as a position apart from the reference position by a certain offset. The amount of change in the start position of the valid image area may be the amount of change in the offset. An example method of calculating the amount of change in the start position of the valid image area with respect to the certain color against the reference color and the amount of change in the width of the valid image area will be described in
In operation 220, the image forming apparatus 100 may detect a position change of a beam with respect to a certain color in a sub-scanning direction, based on a change of a detection time at which the beam with respect to the certain color is detected by the beam detecting apparatus in the sub-scanning direction, against a reference color.
For example, the image forming apparatus 100 may calculate the amount of change of a start position of a valid image area with respect to the certain color in the sub-scanning direction against the reference color, and the amount of change of a distortion of the valid image area, based on the change in the detection time at which the beam is detected in the sub-scanning direction. An example method of calculating the amount of change in the start position of the valid image area with respect to the certain color against the reference color and the amount of change in the distortion of the valid image area will be described in
In operation 230, the image forming apparatus 100 may correct a value of at least one parameter used to perform alignment between an image of the reference color and an image of the certain color, based on the position changes of the beam with respect to the certain color in the main scanning direction and the sub-scanning direction.
For example, the image forming apparatus 100 may correct at least one value of a scan time point of the beam, a frequency of the beam, or an angle of a lens to transmit the beam to the OPC drum, based on the position changes of the beam with respect to the certain color in the main scanning direction and the sub-scanning direction.
The image forming apparatus 100 may correct the value of the at least one parameter used to perform the alignment between the image of the reference color and the image of the certain color, based on the amount of the position change of the beam, without printing a pattern for image alignment on the intermediate transfer medium. Thus, the image forming apparatus 100 may form an image without distortion between colors. That is, the image forming apparatus 100 may increase the image quality, without an additional operation of printing a pattern for image alignment.
The image forming apparatus 100 may perform the operation of detecting the position change of the beam before an image forming job or during the image forming job. The image forming apparatus 100 may detect the position change of the beam during the image forming job and thus data used to perform the image alignment may be stored in an accumulative manner and the number of data samples may be increased to minimize the measuring error.
Referring to
The exposure unit may include a laser scanning unit (LSU) 350 using a laser diode as a light source. As illustrated in
Each beam detecting apparatus may include a first sensor to detect a beam in a main scanning direction 301 indicating a scan direction of an image forming job and a second sensor to detect a beam in a sub-scanning direction 302 indicating a progress direction of the image forming job. For example, each of the first sensor and the second sensor may include a photo diode (PD) sensor, a linear charge coupled device (CCD) sensor, or the like.
As illustrated in
Referring to
For example, the lens in the LSU may be expanded or deformed due to the change of the external temperature. Also, a frame of the LSU for determining positions of a mirror and the lens may be deformed.
As illustrated in
The beam detecting apparatus in the image forming apparatus 100 may detect the position change of the beam in the main scanning direction, based on a change in a detection time at which the beam is detected in the main scanning direction. As an example, a first beam detecting apparatus 421 may be arranged at a start position at which a valid image area of an OPC drum is started and a second beam detecting apparatus 422 may be arranged at an end position at which the valid image area of the OPC drum is ended.
The image forming apparatus 100 may obtain a first detection time at which the beam is detected from a reference position 401 at which scanning of the beam with respect to a certain color is started to the position of the first beam detecting apparatus 421 of the certain color. Also, the image forming apparatus 100 may obtain a second detection time at which the beam is detected from the reference position 401 at which the scanning of the beam with respect to the certain color is started to the position of the second beam detecting apparatus 422 of the certain color.
When the lens 410 is expanded, an angle by which the beam is refracted from the lens 410 is changed. Thus, the first detection time at which the beam is detected by the first beam detecting apparatus 421 before the lens 410 is expanded and the first detection time at which the beam is detected by the first beam detecting apparatus 421 after the lens 410 is expanded may be different from each other. The image forming apparatus 100 may obtain the amount of change in the start position of the valid image area, based on the amount of change in the first detection time.
Likewise, when the lens 410 is expanded, the angle by which the beam is refracted from the lens 410 is changed and the second detection time at which the beam is detected by the second beam detecting apparatus 422 before the lens 410 is expanded and the second detection time at which the beam is detected by the second beam detecting apparatus 422 after the lens 410 is expanded may be different from each other. The image forming apparatus 100 may obtain the amount of change in the end position of the valid image area based on the amount of change of the second detection time.
The image forming apparatus 100 may obtain the amount of change of a width of the valid image area, based on the amount of change in a difference between the second detection time and the first detection time.
A degree of color distortion may be dependent upon the amount of change with respect to a parameter determining the color distortion, wherein the amount of change is different among colors. The image forming apparatus 100 may correct the color distortion based on the amount of change of the parameter with respect to a certain color against a reference color.
Referring to
For example, the image forming apparatus 100 may calculate the amount of change in the start position of the valid image area with respect to the certain color against the reference color in the main scanning direction, based on the change in the detection time at which the beam is detected, from a reference position from which scanning of the beam with respect to each of the reference color and the certain color is started, to a position of a first beam detecting apparatus to detect the start position of the valid image area.
As an example, the image forming apparatus 100 may obtain a first reference detection time at which the beam is detected from the reference position at which the scanning of the beam with respect to the reference color is started to the position of the first beam detecting apparatus with respect to the reference color. Also, the image forming apparatus 100 may obtain a first detection time at which the beam is detected from the reference position at which the scanning of the beam with respect to the certain color is started to the position of the first beam detecting apparatus with respect to the certain color. The image forming apparatus 100 may calculate the amount of change of the start position of the valid image area with respect to the certain color against the reference color in the main scanning direction, based on a difference between the first detection time of the certain color and the first detection time of the reference color. Here, when there is the amount of change of the start position of the valid image area, the image forming apparatus 100 may determine that there is a distortion between the image of the reference color and the image of the certain color.
In operation 520, the image forming apparatus 100 may calculate the amount of change in the width of the valid image area with respect to the certain color against the reference color in the main scanning direction.
For example, the image forming apparatus 100 may calculate the amount of change in the width of the valid image area with respect to the certain color against the reference color in the main scanning direction, based on a change in a detection time at which the beam in the main scanning direction is detected by a first beam detecting apparatus to detect the start position of the valid image area with respect to each of the reference color and the certain color and a change in a detection time at which the beam in the main scanning direction is detected by a second beam detecting apparatus to detect an end position of the valid image area.
As an example, the image forming apparatus 100 may obtain a second reference detection time at which the beam is detected from the reference position from which the scanning of the beam with respect to the reference color is started to a position of the second beam detecting apparatus with respect to the reference color. A reference width of the valid image area with respect to the reference color may be calculated based on a difference between the second reference detection time and the first reference detection time.
Also, the image forming apparatus 100 may obtain a second detection time at which the beam is detected from the reference position at which the scanning of the beam with respect to the certain color is started to the position of the second beam detecting apparatus of the certain color. The width of the valid image area with respect to the certain color may be calculated based on a difference between the second detection time and the first detection time.
The image forming apparatus 100 may calculate the amount of change in the width of the valid image area with respect to the certain color against the reference color, by calculating a difference between the width of the valid image area with respect to the certain color and the reference width of the valid image area with respect to the reference color. Here, when there is the amount of change of the width of the valid image area, the image forming apparatus 100 may determine that there is a distortion between the image of the reference color and the image of the certain color.
Referring to
Referring to a reference signal 610 of the reference color and a detecting signal 620 of the first beam detecting apparatus of the reference color, the image forming apparatus 100 may obtain a first reference detection time by calculating a difference between a time point A_Tm0 611 at a reference position, at which scanning of the beam with respect to the reference color is started, and a time point A_Tm1 621 at which the beam is detected at the position of the first beam detecting apparatus of the reference color.
Referring to the reference signal 610 of the reference color and a detecting signal 630 of the second beam detecting apparatus of the reference color, the image forming apparatus 100 may obtain a second reference detection time by calculating a difference between the time point A_Tm0 611 at the reference position, at which the scanning of the beam with respect to the reference color is started, and a time point A_Tm2 631 at which the beam is detected at the position of the second beam detecting apparatus of the reference color.
A first beam detecting apparatus and a second beam detecting apparatus of a first color may be arranged at a start position and an end position of a valid image area of an OPC drum of the first color, respectively.
Referring to a reference signal 640 of the first color and a detecting signal 650 of the first beam detecting apparatus of the first color, the image forming apparatus 100 may obtain a first detection time by calculating a difference between a time point B_Tm0 641 at a reference position, at which scanning of a beam with respect to the first color is started, and a time point B_Tm1 651 at which the beam is detected at the position of the first beam detecting apparatus of the first color.
Referring to the reference signal 640 of the first color and a detecting signal 660 of the second beam detecting apparatus of the first color, the image forming apparatus 100 may obtain a second detection time by calculating a difference between the time point B_Tm0 641 at the reference position, at which the scanning of the beam with respect to the first color is started, and a time point B_Tm2 661 at which the beam is detected at the position of the second beam detecting apparatus of the first color.
The image forming apparatus 100 may obtain a change amount B_TD1 652 of the detection time at which the start position of the valid image area is detected, by calculating a difference between the first detection time and the first reference detection time.
The image forming apparatus 100 may obtain the amount of time change corresponding to the reference width of the valid image area with respect to the reference color, by calculating a difference between the first reference detection time and the second reference detection time. The image forming apparatus 100 may obtain the amount of time change corresponding to the width of the valid image area with respect to the first color, by calculating a difference between the first detection time and the second detection time. Also, the image forming apparatus 100 may obtain the amount of time change B_TD2 662 corresponding to the amount of change of the width of the valid image area with respect to the certain color against the reference color, by calculating a difference between the amount of time change corresponding to the reference width of the reference color and the amount of time change corresponding to the width of the first color.
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In the example of
When the angles of the mirrors 823 and 824 are changed due to the change in the external temperature, the position of the beam may be changed to a forward position 851 or a rearward position 852 with respect to previous positions 841 and 842 of the beam, in the sub-scanning direction.
Referring to
For example, the image forming apparatus 100 may calculate the amount of change of the start position of the valid image area with respect to the certain color in the sub-scanning direction, against the reference color, based on a change of a detection time at which a beam is detected from a pixel data read trigger signal with respect to each of the reference color and the certain color.
As an example, the image forming apparatus 100 may obtain a third reference detection time at which the beam is detected from the pixel data read trigger signal with respect to the reference color. Also, the image forming apparatus 100 may obtain a third detection time at which the beam is detected from the pixel data read trigger signal with respect to the certain color. The image forming apparatus 100 may calculate the amount of change of the start position of the valid image area with respect to the certain color in the sub-scanning direction, against the reference color, based on a difference between the third detection time of the certain color and the third reference detection time of the reference color. Here, when there is the amount of change of the start position of the valid image area, the image forming apparatus 100 may determine that there is a distortion between an image of the reference color and an image of the certain color.
In operation 920, the image forming apparatus 100 may calculate the amount of change in the distortion of the valid image area with respect to the certain color in the sub-scanning direction, against the reference color.
For example, the image forming apparatus 100 may calculate the amount of change in the distortion of the valid image area with respect to the certain color in the sub-scanning direction, against the reference color, based on a change in a detection time at which the beam in the sub-scanning direction is detected by a first beam detecting apparatus to detect the start position of the valid image area with respect to each of the reference color and the certain color and a change in a detection time at which the beam in the sub-scanning direction is detected by a second beam detecting apparatus to detect an end position of the valid image area.
Referring to
As illustrated in the image 1010 of
Referring to a graph 1020 of
For example, the image forming apparatus 100 may detect a central point of a rising edge and a falling edge and a central point of a falling edge and a rising edge and may determine a position of a pixel, the position corresponding to the central point, as a position in which the beam is detected.
Referring to
Referring to a pixel data read trigger signal 1110 and a detecting signal 1130 of the first beam detecting apparatus of the reference color, the image forming apparatus 100 may obtain a third reference detection time at which the beam in the sub-scanning direction is detected by the first beam detecting apparatus of the reference color. The image forming apparatus 100 may determine a time at a central point of a rising edge and a falling edge in the detecting signal 1130 as the third reference detection time. The third reference detection time may be A_Ts1 1131. The image forming apparatus 100 may obtain the start position of the valid image area of the reference color from a position of a pixel corresponding to the central point of the rising edge and the falling edge in the detecting signal 1130. Referring to a pixel number 1120, the pixel corresponding to the central point may be a third pixel.
Referring to the pixel data read trigger signal 1110 and a detecting signal 1140 of the second beam detecting apparatus of the reference color, the image forming apparatus 100 may obtain a fourth reference detection time at which the beam in the sub-scanning direction is detected by the second beam detecting apparatus of the reference color. The image forming apparatus 100 may determine a time at a central point of a rising edge and a falling edge in the detecting signal 1140 as the fourth reference detection time. The fourth reference detection time may be A_Ts2 1141. The image forming apparatus 100 may obtain the end position of the valid image area of the reference color from a position of a pixel corresponding to the central point of the rising edge and the falling edge in the detecting signal 1140. Referring to the pixel number 1120, the pixel corresponding to the central point may be the third pixel.
A first beam detecting apparatus and a second beam detecting apparatus of a first color may be arranged at a start position and an end position of a valid image area of an OPC drum of the first color, respectively.
Referring to the pixel data read trigger signal 1110 and a detecting signal 1150 of the first beam detecting apparatus of the first color, the image forming apparatus 100 may obtain a third detection time at which the beam in the sub-scanning direction is detected by the first beam detecting apparatus of the first color. The image forming apparatus 100 may determine a time at a central point of a rising edge and a falling edge in the detecting signal 1150 as the third detection time. The third detection time may be B_Ts1 1151. The image forming apparatus 100 may obtain the start position of the valid image area of the first color from a position of a pixel corresponding to the central point of the rising edge and the falling edge in the detecting signal 1150. Referring to the pixel number 1120, the pixel corresponding to the central point may be a fourth pixel.
Referring to the pixel data read trigger signal 1110 and a detecting signal 1160 of the second beam detecting apparatus of the first color, the image forming apparatus 100 may obtain a fourth detection time at which the beam in the sub-scanning direction is detected by the second beam detecting apparatus of the first color. The image forming apparatus 100 may determine a time at a central point of a rising edge and a falling edge in the detecting signal 1160 as the fourth detection time. The fourth detection time may be B_Ts2 1161. The image forming apparatus 100 may obtain the end position of the valid image area of the first color from a position of a pixel corresponding to the central point of the rising edge and the falling edge in the detecting signal 1160. Referring to the pixel number 1120, the pixel corresponding to the central point may be an eighth pixel.
For example, the image forming apparatus 100 may obtain a change amount B_TD3 1152 of the detection time by calculating a difference between the third detection time and the third reference detection time. The image forming apparatus 100 may calculate the amount of change in the start position of the valid image area with respect to the first color against the reference color in the sub-scanning direction, based on the change amount B_TD3 1152 of the detection time.
For example, the image forming apparatus 100 may obtain a change amount B_TD4 1162 of the detection time by calculating a difference between the third detection time and the fourth detection time. The image forming apparatus 100 may calculate the amount of change in distortion of the first color in the sub-scanning direction, based on the change amount B_TD4 1162 of the detection time.
For example, the image forming apparatus 100 may obtain a change amount of the detection time by calculating a difference between the third reference detection time and the fourth reference detection time. The image forming apparatus 100 may calculate the amount of change in distortion of the reference color in the sub-scanning direction, based on the change amount of the detection time. Here, when the change amount of the detection time is 0, the image forming apparatus 100 may determine that there is no distortion of the reference color in the sub-scanning direction.
For example, the image forming apparatus 100 may obtain a change amount of the detection time by calculating a difference between the fourth detection time and the fourth reference detection time. The image forming apparatus 100 may calculate the amount of change in the end position of the valid image area with respect to the first color against the reference color in the sub-scanning direction, based on the change amount of the detection time.
For example, the image forming apparatus 100 may calculate the amount of change in the distortion of the valid image area with respect to the first color against the reference color in the sub-scanning direction, based on a difference between the amount of change in the start position of the valid image area with respect to the first color against the reference color in the sub-scanning direction and the amount of change in the end position of the valid image area with respect to the first color against the reference color in the sub-scanning direction.
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The diode 1310 may irradiate a beam used for an image forming job. The diode 1310 may be included in an LSU of the image forming apparatus 1300. The beam detecting apparatus 1320 may detect a beam in a main scanning direction and a beam in a sub-scanning direction of the image forming job. Here, the main scanning direction may indicate a scan direction of the image forming job and the sub-scanning direction may indicate a progress direction of the image forming job.
The beam detecting apparatus 1320 may include a first sensor to detect the beam in the main scanning direction and a second sensor to detect the beam in the sub-scanning direction. For example, each of the first sensor and the second sensor may include a PD sensor, a linear CCD sensor, or the like.
The beam detecting apparatus 1320 may be arranged between each of arrays of OPC drums with respect to a plurality of colors and the LSU. Also, the beam detecting apparatus 1320 may be arranged at each of a start position and an end position of a valid image area of each of the OPC drums. Here, the start position of the valid image area may be the right side based on the sub-scanning direction and the end position of the valid image area may be the left side based on the sub-scanning direction. The beam detecting apparatus 1320 may be arranged at an outer edge around the valid image area of each of the OPC drums.
The memory 1330 may store programs, data, or files related to the image forming apparatus 1300. The processor 1340 may execute the programs stored in the memory 1330, read the data or files stored in the memory 1330, or store new files in the memory 1330. The memory 1330 may store program commands, data files, data structures, etc. singularly or in a combined way. The memory 1330 may store instructions executable by the processor 1340.
The processor 1340 may control an operation of the image forming apparatus 1300 and may include at least one processor, such as a central processing unit (CPU). The processor 1340 may include at least one specialized processor corresponding to each function or may be an integrated-type processor.
The processor 1340 may detect a position change of a beam with respect to a certain color in the main scanning direction, based on a change in a detection time at which the beam with respect to the certain color is detected by the beam detecting apparatus 1320 in the main scanning direction, against a reference color.
For example, the processor 1340 may calculate the amount of change of a start position of a valid image area with respect to the certain color against the reference color in the main scanning direction and the amount of change of a width of the valid image area, based on a change in the detection time at which the beam is detected in the main scanning direction.
The processor 1340 may calculate the amount of change in the start position of the valid image area with respect to the certain color against the reference color in the main scanning direction, based on a change in a detection time at which the beam is detected, from a reference position from which scanning of the beam with respect to each of the reference color and the certain color is started, to a position of the first beam detecting apparatus to detect the start position of the valid image area.
The processor 1340 may calculate the amount of change in the width of the valid image area with respect to the certain color against the reference color in the main scanning direction, based on a change in a detection time at which the beam is detected in the main scanning direction by the first beam detecting apparatus to detect the start position of the valid image area with respect to each of the reference color and the certain color, and a change in a detection time at which the beam is detected in the main scanning direction by the second beam detecting apparatus to detect an end position of the valid image area with respect to each of the reference color and the certain color.
The processor 1340 may detect a position change of the beam with respect to a certain color in the sub-scanning direction, based on the change in the detection time at which the beam with respect to the certain color is detected by the beam detecting apparatus 1320 in the sub-scanning direction, against the reference color.
For example, the processor 1340 may calculate the amount of change in the start position of the valid image area with respect to the certain color against the reference color in the sub-scanning direction, and the amount of change in distortion of the valid image area, based on the change in the detection time at which the beam is detected in the sub-scanning direction.
The processor 1340 may calculate the amount of change in the start position of the valid image area with respect to the certain color against the reference color in the sub-scanning direction, based on a change in a detection time at which the beam is detected from a pixel data read trigger signal with respect to each of the reference color and the certain color.
The processor 1340 may calculate the amount of change in distortion of the valid image area with respect to the certain color against the reference color in the sub-scanning direction, based on a change in a detection time at which the beam is detected in the sub-scanning direction by the beam detecting apparatus 1320 to detect the start position of the valid image area with respect to each of the reference color and the certain color and a change in a detection time at which the beam is detected in the sub-scanning direction by the second beam detecting apparatus to detect an end position of the valid image area with respect to each of the reference color and the certain color.
The processor 1340 may correct a value of at least one parameter used to perform alignment between an image of the reference color and an image of the certain color, based on the position changes of the beam with respect to the certain color in the main scanning direction and the sub-scanning direction.
For example, the processor 1340 may correct at least one value of a scan time point of the beam, a frequency of the beam, or an angle of a lens transmitting the beam to an OPC drum, based on the position changes of the beam with respect to the certain color in the main scanning direction and the sub-scanning direction.
For example, when the start position of the valid image area is changed because the position of the beam is changed in the main scanning direction or the sub-scanning direction, the processor 1340 may adjust the scan time point of the beam to make the start positions of the valid image areas with respect to colors correspond to one another.
For example, when the width of the valid image area is changed because the position of the beam is changed in the main scanning direction, the processor 1340 may adjust the frequency of the beam based on the amount of change in the width of the valid image area, to make the widths of the valid image areas with respect to the colors correspond to one another.
For example, when distortion occurs in the valid image area because the position of the beam is changed in the sub-scanning direction, the processor 1340 may adjust the angle of the lens based on the amount of change in the distortion of the valid image area, to align images with respect to the colors.
The processor 1340 may obtain an initial value of at least one parameter used to align the position of the beam or an image having a plurality of colors aligned, in a state in which the image is generated. The memory 1330 may store the initial value of the at least one parameter corresponding to the state in which the image having the plurality of colors aligned is generated. The processor 1340 may correct a value of the at least one parameter based on distortion among the colors and the initial value of the at least one parameter.
The operating method of the image forming apparatuses 100 and 1300 described above may be implemented by a non-transitory computer-readable recording medium storing instructions or data executable by a computer or a processor. The operating method of the image forming apparatuses 100 and 1300 may be written as a program executable by a computer and may be implemented by a general-purpose digital computer to operate the program by using a computer-readable recording medium. The computer-readable recording medium may include read-only memory (ROM), random-access memory (RAM), flash memory, CD-ROMs, CD−Rs, CD+Rs, CD−RWs, CD+RWs, DVD-ROMs, DVD−Rs, DVD+Rs, DVD−RWs, DVD+RWs, DVD-RAMs, BD-ROMs, BD-Rs, BD-R LTHs, BD-REs, a magnetic tape, a floppy disk, a magneto-optic data storage device, an optical data storage device, a hard disk, a solid-state disk (SSD), and any other device capable of storing instructions or software, related data, data files, and data structures and providing the instructions, software, related data, data files, and data structures to a processor or a computer so that the processor or the computer execute the same.
While the examples have been particularly shown and described with reference to examples thereof and the drawings, it will be understood by one of ordinary skill in the art that various changes and modifications may be made based on the descriptions. For example, appropriate results may be accomplished when the described techniques are executed in different orders from the methods described above, and/or the described components, such as the system, structure, device, circuit, etc., are combined or assembled in different forms from the methods described above, or replaced or substituted by other components or equivalents. Therefore, the scope of the disclosure is indicated by the following claims and equivalents of the claims and should not be construed as limited to the examples described herein.
Number | Date | Country | Kind |
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10-2019-0071091 | Jun 2019 | KR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/US2020/012452 | 1/7/2020 | WO | 00 |