JP2002300389A - Printer and calibration method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the deterioration in the print throughput by calibration for each of a plurality of the image processing processes for a printer that can execute a plurality of image processing processes for a printer that can execute a plurality of image processing processes depending on kinds of a printed image or the like. SOLUTION: When a dither pattern emphasizing the gradation and a dither pattern emphasizing the resolution are used for binarization process in an output processing 3008 with respect to image processing, the calibration conducted by way of user's operation before start of print is applied only to the image processing emphasizing the resolution and the calibration conducted not through the user's operation during printing is applied to both the image processing processes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a printing apparatus and a calibration method, and more particularly, to processing for emphasizing the resolution or emphasizing gradation in accordance with the type of a printing target such as characters and images. The present invention relates to calibration of a printing apparatus capable of performing a process of performing printing.

[0002]

2. Description of the Related Art Printers and copiers are generally known as printing apparatuses. In these printing apparatuses, when printing, an image or a character obtained thereby is subjected to image processing that emphasizes resolution,
Alternatively, it is possible to set whether to perform image processing with emphasis on gradation. Thus, for example, when printing a photo-like image, it is possible to print an image with a smooth density change by setting image processing with emphasis on gradation, and when printing a character or a line drawing, etc. In addition, it is possible to print a character or the like having a clear outline by setting image processing with emphasis on resolution.

In some printing apparatuses, so-called calibration is performed to maintain printing characteristics such as density and gradation that are realized in printing by the printing apparatus. This is because the printing characteristics may change due to a relatively long printing operation or aging of the apparatus, making it impossible to maintain a constant print quality.

In the calibration, first, a predetermined pattern is output by printing or the like, and the output result is referred to as a densitometer,
Reading is performed using a reading device such as a scanner or a sensor.
Then, calibration data is obtained by comparing the read result with predetermined data used in outputting the pattern, and based on the data, for example, calibration for density characteristics (or gradation) is performed. If there is, the content of the gamma correction table in the image processing is updated.

Conventionally, when calibration is performed in a printing apparatus that can set image processing corresponding to each of the above-described print targets, calibration is usually performed for all settable image processing. .

[0006]

However, the calibration is often performed at a predetermined timing before the start of printing or during printing, and in all cases, the image processing which can be set uniformly as described above is performed. Performing each calibration for all of them has the problem that more time is spent for that and the throughput of the printing apparatus is reduced.

In this case, the calibration performed during printing is generally such that all of the processing is automatically performed in the apparatus, and is performed before printing is started.
For example, the processing time is shorter than that of the calibration that requires the user of the apparatus to scan the paper on which the pattern is printed and set the sheet on the reading apparatus.

On the other hand, the print characteristics such as the gradation and the resolution, which individually provide image processing corresponding to the characteristics, are as follows.
There is also the fact that they do not have an equal effect on print quality and therefore there may be differences in the frequency of calibration between these print characteristics.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and an object of the present invention is to provide a printing apparatus capable of executing a plurality of image processes according to the type of an image to be printed and the like. Provided is a printing apparatus and a calibration method that can reduce a decrease in throughput due to calibration by performing calibration on a combination of appropriate image processing and calibration content in consideration of the content of calibration or the processing time thereof. Is to do.

[0010]

According to the present invention, there is provided:
In a printing apparatus capable of performing printing based on respective print data generated by a plurality of image processings having different processing modes, a calibration is performed for each of the plurality of image processings so that a printing characteristic of the printing apparatus is constant. A first calibration means capable of performing a plurality of image processing,
A calibration capable of performing a calibration for keeping print characteristics of the printing apparatus constant, wherein the first calibration means and a second calibration means having a different aspect of the calibration; The second calibration unit performs calibration for each of the plurality of image processes, and the first calibration unit performs a calibration performed by the second calibration unit among the plurality of image processes. And control means for performing control so as to perform calibration for a smaller number of image processes than image processes related to the image processing.

In a calibration method for a printing apparatus capable of performing printing based on respective print data generated by a plurality of image processings having different processing modes, the printing apparatus may perform printing for each of the plurality of image processings. A first calibration unit capable of performing a calibration for maintaining the printing characteristics of the printing apparatus, and a calibration for maintaining the printing characteristics of the printing apparatus for each of the plurality of image processes. Wherein the first calibration means and a second calibration means having a different aspect of the calibration are provided, and the second calibration means performs the plurality of image processing operations. Perform calibration for each Wherein the calibration means controls to perform calibration for a smaller number of image processings than the image processing related to calibration performed by the second calibration means among the plurality of image processings. And

According to the above arrangement, the execution of the first calibration means and the second calibration means for a plurality of image processings, and the first calibration means relates to the calibration performed by the second calibration means. Since the calibration is performed for a smaller number of image processes than the image processing, the first calibration requires a relatively long time to be executed, and if the corresponding image process is appropriately set, the printing related to the image process can be performed. The time required for calibration as a whole can be reduced while minimizing deterioration of characteristics.

[0013]

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

One embodiment of the present invention relates to a printing system in which a unit to which a reader for reading a document is connected to a printer performs printing or reading of a document in response to an instruction from a host computer. Apart from
It can execute a mode of operating as a printer and a mode of operating as a copier using a reader.

1. Configuration of the Entire System FIG. 1 is a block diagram schematically showing the configuration of the printing system and the main configuration of each element such as a printer constituting the system.

As shown in FIG. 1, the present system provides a reader controller 1 in the form of a board to a printer 2001.
06 can be removably attached to the reader 101.
Can be connected to read the original. Then, the printing operation by the printer 2001 or the reader 1
01 is performed based on an instruction from a host computer (hereinafter, also simply referred to as a host) 2104.

The reader 101 irradiates a document placed on a document table 102 with light from a light source 103, and the reflected light is input to a photoelectric conversion device 104 having a CCD via a predetermined optical system. . Thus, a document image such as a character or an image can be read as an electric signal. And
This read data signal is supplied to the analog-to-digital converter 105.
Is converted to a digital signal by the
Sent to 1.

The reader controller 106 mounted on the printer 2001 performs predetermined image processing on the read data signal obtained by reading, starting with giving an instruction on the above-mentioned reading operation by the reader 101, and forms an image. Processing for generating a print signal used in the unit 2003 is performed.

Printer controller (in this embodiment,
Also called PDL controller. ) 2103 is the host 2
The image forming unit 20 controls the printing operation of the printer based on an instruction signal from the printer 104 or performs predetermined image processing on a print data signal sent from the host 2104.
03, a print data signal is generated. The DC controller 2002 controls a printing operation of the image forming unit 2003 based on a print signal generated by the reader controller 106 or a print signal generated by the printer controller 2103. The image forming unit of the present embodiment is of an electrophotographic type, and forms a latent image on a photosensitive drum by laser light emitted by a laser according to print data, and attaches toner to the latent image to develop the latent image in accordance with the print data. To form Then, printing can be performed by transferring the toner image to paper as a print medium.

The printer 2001 of this embodiment can be equipped with a paper cassette deck 2004 that can be added as an option, and can also be equipped with an optional sorter 2005. The operation of these cassette deck 2004 and sorter 2005 is controlled by an option controller.

In this embodiment, as described above, since the reader controller 106 is mounted on the printer body in the form of a board, the DC controller 20
02 and a printer controller 2103 without an external cable for communication control.

2. Configuration When No Reader Controller is Mounted As described above, the reader controller 106 can be attached to and detached from the printer. First, the configuration in which the reader controller is not mounted, that is, the present printer is used only as a printer. The configuration in that case will be described.

FIG. 2 is a diagram showing a configuration when a reader controller is not mounted in the printer 2001 shown in FIG. 1. FIG. 3 shows an example of a configuration when the printer 2001 is used only for printing as described above. FIG. 2 is a block diagram illustrating an information processing system using such a printer via a network.

As shown in the figure, when the reader controller is not mounted, in the present embodiment, the printer controller 2 is used.
A video I / F 21 is provided between the printer 103 and the DC controller 2002 shown in FIGS.
01, and communication between them can be performed. The DC controller 2002 includes an I / F 2101
The image forming unit 2003 can be controlled based on a print data signal received via the printer, and can output a sheet on which characters, images, and the like are formed. The DC controller 2002 also has a function of detecting various states in the printer and notifying the printer controller 2103 of the detected state.

The printer controller 2103 receives the print data sent from the host computer 2104 or via the network 2105 as described above. This includes print data in bitmap format,
It is sent in various formats such as print data in PDL (Page Description Language) format. And
After expanding this data in a predetermined memory, the data such as PDL is converted into raster format data, and then the print data is transferred to the DC controller 2002.

Next, details of the video I / F 2101 connecting the printer controller and the printer will be described with reference to FIG.

A printer controller 2103 and a DC controller (hereinafter also referred to as an engine control unit) 200
The video I / F 2101 between the two exchanges signals shown in FIG. FIG. 5 shows this video I / F.
A list of signals is shown, but only the representative signals shown in FIG. 4 will be described here.

First, after the power is supplied to the printer, / PPRDY 203 finishes processing such as initialization,
This signal indicates that communication with the printer controller 2103 has become possible. / CPRDY 204 is a signal indicating that power has been supplied to the printer controller 2103 and communication with the engine control unit 2002 has become possible after processing such as initialization has been completed.

The / RDY signal 205 is output from the engine control unit 2
Reference numeral 002 denotes a signal indicating that a print operation has been enabled in response to a print start instruction (/ PRNT signal described later) from the printer controller 2103. The condition that this signal becomes true depends on whether the temperature inside the fixing unit has reached a predetermined temperature,
This is only when each part of the printer is operating normally, such as whether the paper remains in the printer or whether the polygon mirror is rotating at a predetermined speed. / PRNT signal 2
Reference numeral 06 denotes a signal for the printer controller 2103 to instruct the engine control unit 2002 to start or continue a printing operation.

The / TOP signal 207 is output from the engine control unit 2
This is a synchronization signal that is passed from the 002 to the printer controller 2103 and serves as a reference for vertical scanning of an image. This signal corresponds to the signal of 206
3, after a certain period of time. on the other hand,
/ LSYNC signal 208 is transmitted to the printer controller 21
03 is a synchronization signal used as a reference for horizontal scanning.
Similar to the signal 207, the signal 206 is output from the printer controller 2103 to the printer controller 2103 after a predetermined time. Further, the / VCLK signal 209 is a signal / VDOEN2 described later.
10 and a synchronous clock for the / VDO signal 211, and generates a clock having a frequency corresponding to the print data signal from the printer controller 2103.

The / VDOEN signal 210 is a signal for controlling the capture of the print data signal output from the printer controller 2103 into the engine control unit 2002. That is, the engine control unit 2002 outputs the / VCLK signal 2
In synchronization with 09, it is detected whether this signal is TRUE or FALSE. In the case of TRUE, the print data signal is captured, and in the case of FALSE, the capture is not performed.

The / VDO signal 211 is a print data signal. The printer controller 2103 outputs the / TOP signal 207 in the vertical direction and / LS signal in the horizontal direction.
The print data signal / VDO signal 211 is output in synchronization with the / VCLK signal 209 based on the YNC signal 208 as a reference.

The / CCLK signal 212 is transmitted from the printer controller 2103 to the engine controller 2
002, and a synchronous clock when the engine control unit 2002 returns a serial status to the printer controller 2103. The synchronous clock is output from the printer controller 2103. The / CBSY signal 213 is a signal indicating to the engine control unit 2002 that the printer controller 2103 is transmitting a serial command using the / CMD signal 214 described later.
The / CMD signal 214 is transmitted to the printer controller 21
A signal 03 is used when transmitting serial information to the engine control unit 2002.

The / SBSY signal 215 indicates to the printer controller 2103 that the engine control unit 2002 has returned a serial status using the / STS signal 216.
This is the signal shown in FIG. The / STS signal 216 is a signal used when the engine control unit 2002 returns serial information to the printer controller 2103.
The serial information is called status.

The / CCRT signal 217 is output when the printer internal status changes.
3 is a signal to be reported. When the printer controller 2103 receives this report signal, it issues a command inquiring about what has changed in the state of the engine using the / CMD signal 214, and the engine control unit 2002 responds to the command with the / STS signal 216. Notify status.

Next, the mechanical configuration of the printer 2001 will be described in detail with reference to FIG.

FIG. 6 is a front view of the inside of the printer 2001. In the figure, reference numeral 401 denotes a laser unit, which receives a print data signal / VDO sent from a printer controller 2103 (see FIGS. 1 to 3), converts the print data signal into a laser beam, and irradiates the photoconductor 402 with the laser beam. A latent image is formed on 402. Photoconductor 402
Is rotated in the counterclockwise direction in FIG.
03 and the black developing device 404 cause toner to adhere thereto in accordance with the charged electric charge, thereby performing development. When the print image or the like is monochrome, only the developing device 404 operates, and when the image is color, both the developing devices 403, 4
04 is used. Next, the image or the like generated on the photoconductor is transferred to the intermediate transfer body 405 rotating clockwise. The intermediate transfer member performs one rotation in the case of black and white and four rotations in the case of color, and forms an image thereon.

On the other hand, the paper fed from the upper cassette 408 or the lower cassette 409 by the respective pickup rollers 411 or 412 is transported by the corresponding paper feed rollers 413 or 414, respectively, and further transported by the transport rollers 415. It is transported to the registration position.

Then, at the timing when the image formation in the intermediate transfer member 405 is completed, the intermediate transfer member 4
Further, the sheet conveyance is controlled at such a timing that the sheet reaches between the transfer belt 05 and the transfer belt 406. When the paper reaches this position, the transfer belt comes into contact with the intermediate transfer member, and the toner is transferred to the recording paper. Then, the image and the like transferred to the paper are fixed on the paper by heat and pressure by a fixing roller 407.

The sheet on which an image or the like is fixed is conveyed to one of a face-up discharge port 417 or a face-down discharge port 418 specified in advance by the printer controller 2103 and discharged. As described above, printing can be performed based on the print data signal sent from the printer controller 2103.

Next, the timing of signals exchanged between the video I / Fs will be described with reference to FIG. This shows the description of the video I / F described above with reference to FIG. 4 as time elapses.

First, when the printer controller 2103 completes the preparation of image information, the / PRNT signal is set to Low.
(True) and inform the engine control unit 2002. At the same time, an image synchronization signal / VCLK signal used for transferring the print data signal is also generated. In response, the engine control unit 2002 performs various settings and the like inside the printer, and when print data can be accepted,
A TOP signal and a / LSYNC signal are output to the printer controller 2103. This vertical synchronization signal / TOP
The printer controller 2103 sends the print data signal / VDO and the image valid signal / VDOEN to the engine control unit 2002 in accordance with the horizontal synchronization signal / LSYNC.
Forward to

FIG. 8 is a diagram showing what kind of commands and statuses are exchanged by serial communication during these printing operations. FIG. 8 shows the timing of communication between the printer controller 2103 and the engine control unit 2002. These are shown.

The case where the lowermost / CCRT signal shown in FIG. 8 is not used will be described. Printer controller 2
When the 103 wants to issue a command to the engine control unit 2002, it sets the / CBSY signal to Low (true) and sends command data to the / CMD signal in synchronization with the clock signal / CCLK. The engine control unit 2002 that has received it confirms that the / CBSY signal is High (false), sets / SBSY to Low (true), and generates the engine-side status data corresponding to the command from the printer controller 2103. / CCL
Send to / STS in synchronization with K signal. This status data is received by the printer controller 2103, and print control is continued or interrupted depending on the state.

Next, the / CCRT signal will be described.
This signal is sent to the printer controller 2103 in advance.
Is a signal that becomes low (true) when a change occurs in the state of the designated engine (image forming unit) side. For example, the printer controller 2103 preliminarily sets the / CCRT signal to be valid when paper-out occurs.
Set by CMD. So there is only one sheet left,
When the printer controller 2103 issues a printout request for two sheets, the print sequence operation for the first sheet is normally processed without any problem. In this case, since the second sheet is not present, the printer engine detects a change in the state when the printing of the second sheet is started.
/ CCRT signal is changed from High to Low. This signal is transmitted to the printer controller 2103. Upon detecting this, the printer controller 2103 immediately issues a command requesting the paper presence status to the engine control unit 2002 in order to know which paper cassette is out of paper. Accordingly, the engine control unit 2002 returns the status of the paperless cassette to the controller. The / CCRT signal is cleared to High at the timing when the status is returned and the / SBSY signal becomes Low.

FIG. 9 is a diagram showing more specifically the exchange of commands / status between the printer controller 2103 and the engine control unit 2002. The printing operation will be described with reference to FIG. Here, the case of color printing will be described.

When a print (print) start request is issued, the printer controller 2103 checks the ready state of the printer with the engine control unit 2002 while performing print data conversion processing and the like. Next, a command for designating a paper feeding stage is issued. Further, a command for requesting the sheet size in the designated cassette is issued. In response to these series of commands, the engine control unit 2002 returns a corresponding status.

Next, the discharge port is determined by the command for specifying the discharge port, and a page mode designation command for designating how many pages to print is issued. Finally, by issuing a command for specifying monochrome / color, all settings on the printer side are completed.

Thereafter, the printer controller 2103 sends a print request / PR to the engine control unit 2002.
Generate an NT signal. In response to this, a / TOP signal is returned from engine control unit 2002 for a predetermined time.
The vertical scanning direction is synchronized with this / TOP signal, and
The print data is transferred to the engine control unit 2002 in synchronization with the LSYNC signal in the horizontal direction and the / VDO signal is adjusted to / VCLK. Here, since the color mode is set, the / TOP signal is generated four times, and an image or the like for four colors of CMYK is formed.

After the generation of the final / TOP signal,
Return the PRNT signal to High (false). As a result, the engine control unit 2002 detects that the print request has been completed, and shifts to post-processing such as a cleaning operation of the intermediate transfer body. Further, the transferred sheet passes through the fixing roller and is discharged to a designated discharge port. Finally, the printer controller 2103 confirms to the engine control unit 2002 that the sheet is not in the sheet conveyance state (end of sheet discharge), ends printing, and waits in a ready state until the next print request is issued.

During the operation as described above, the paper jam, the absence of the paper described above, the door opening by the user, etc.
When an abnormal state occurs, a printer abnormality is immediately transmitted from the engine control unit 2002 to the printer controller 2103 using the aforementioned / CCRT signal. The printer controller 2103 performs corresponding processing.

3. Configuration when a Reader Controller is Mounted Next, a printing system according to the present embodiment in which a reader controller is mounted and a reader can be used to perform a copying operation in addition to the above printing operation will be described.

FIG. 10 is a diagram showing a printer and a reader having the same configuration as that of FIG. 1, and is a diagram showing a mechanical configuration when a reader controller 106 in the form of a board is mounted on the printer 2001.

In FIG. 10, reference numeral 801 denotes a document feeder constituting the reader 101, which is a device for conveying a document sheet to a portion which can be read optically. Similarly, 8
02 indicates an optical reading device, and 805 indicates a platen glass. The document feeding device 801 is provided with an optical reading device 80.
When the original is transported onto the original platen glass 805 by the feeder 801, the optical reader 802 scans the image paper while moving in the horizontal direction in FIG. The processed reflected light is sent to the photoelectric conversion unit 104.

FIG. 11 shows a printer controller 2103.
FIG. 6 is a diagram showing an electrical connection when a reader controller 106 is mounted between the engine controller 2002 and the engine controller 2002.

The types of signals shown in the figure have basically the same functions as the types of signals described above with reference to FIG. However, since the signal between the printer controller 2103 and the engine control unit 2002 described above with reference to FIG. 4 is physically different, the signal name between the reader controller and the printer controller is denoted by C before the signal name. , And a signal between the engine control unit and P is distinguished by adding P.

In the reader controller 106, 90
Reference numeral 2 denotes an image signal processing unit which performs predetermined image processing on a signal read by the reader 101. Reference numeral 903 denotes a document scanning optical system control unit that controls the operation of the optical reading device 802, and reference numeral 904 denotes a document feeding control unit that controls the operation of the document feeding device 801. An operation unit 905 allows the user to perform a predetermined operation related to reading by a reader. An image input unit 906 receives the print data signal converted by the photoelectric conversion unit 804 and transfers the print data signal to the image signal processing unit 902 of the reader controller 106.

FIG. 12 is a block diagram showing a detailed configuration of the reader controller 106.

Referring to FIG.
Is provided with the image processing unit 902 shown in FIG.
Similarly, an image read by the reader 101 is input to the image processing unit 902 from the image input unit illustrated in FIG. Reference numeral 2201 denotes a selector. The selector 2201 selects either the output of the image processing unit 902 or the signal sent from the printer controller 2103 and outputs the selected signal to the engine control unit 2002 according to the setting of the copy mode or the printer mode. . The signal system switched by the selector 2201 includes an image clock / VCLK and an image enable / VDO.
EN and image data / VDO.

Reference numeral 2202 denotes a serial communication controller for communicating with the engine control unit 2002. 2203
Indicates an input / output port for exchanging signals for supplementing communication in the communication controller 2202. Reference numeral 2204 denotes an interrupt controller. Interrupt controller 2
An image leading end request signal / PTOP and a printer state change signal / PCCRT are input to 204. Reference numeral 2205 denotes a serial communication controller that communicates with the printer controller 2103. Reference numeral 2206 denotes an input / output port for exchanging signals for supplementing communication in the communication controller 2205. 2207 is a gate,
It controls whether the signal sent from the printer is sent to the printer controller 2103 or not. The target of the gate control is the image leading end request signal / TOP and the line synchronization signal / LSYNC. Reference numeral 2208 denotes a control circuit having a gate function and a flag setting function, and this circuit controls the printer state change signal / CCRT. That is, by opening and closing the gate, the engine control unit 2
002 controls the printer status change signal / PCCRT to be transmitted to the printer controller 2103, and sets a flag so that the reader controller can issue the printer status change signal / CCRT to the printer controller 2103. . 220
9 is a CP that controls the entire reader controller described above.
Indicates U.

3.1 Operation in Copy Mode The operation in the copy mode described above with reference to FIGS. 10 to 12 and made possible by attaching the reader and the reader controller to the printer will be described.

When a copy start key (not shown) on the operation unit 905 (see FIG. 11) is operated, the reader controller 106 closes the gate unit 2207 and the signal control 2208 for the copy mode, 2201 is set so that the output of the image processing unit 902 is selected. Next, using the input / output port 2203, the engine control unit 2
For 002, the ready status signal / PRDY of the printer is checked. Next, the serial communication controller 220
Various settings are made by using 2. First, a command for designating a paper feeding stage is issued. Further, a command for requesting the sheet size in the designated cassette is issued. The engine control unit 200 responds to these series of commands.
2 returns the corresponding status.

Next, the discharge port is determined by a command for specifying the discharge port, and a page mode designation command for designating how many pages to print is issued. Finally, by issuing a command for specifying monochrome / color, all settings on the printer side are completed.

When a document is fed onto a document table by document feeding device 801, reader controller 106 issues a print request / PPRNT signal to engine control unit 2002. In response to this, the engine control unit 2002 returns a / PTOP signal after a predetermined time. This is processed by the interrupt controller 2204, and the / P
The optical reading device 802 is synchronized with the TOP signal.
To work. The vertical scanning direction is synchronized with the / PTOP signal, the horizontal direction is further synchronized with the / PLSYNC signal, the / PVDO signal is synchronized with / PVCLK, and the signal input from the photoelectric conversion device 804 to the image processing unit 902 is synchronized. The data is transferred to the engine control unit 2002. Here, since the color mode is set, the optical reading device 2002
Is operated four times, and an image for four colors of CMYK is formed in response to the / PTOP signal generated four times.

Then, after generation of the final / PTOP signal,
Return the / PPRNT signal to High (false). As a result, the engine control unit 2002 detects that the print request has been completed, and shifts to post-processing such as an intermediate transfer body cleaning operation. Further, the transferred sheet passes through the fixing roller and is then discharged to a specified discharge port. Finally, the reader / controller confirms to the engine control unit 2002 that the recording sheet is not in the recording paper transport state (end of paper discharge), ends printing, and waits in a ready state until the next print request is issued.

3.2 Operation in Print (Print) Mode Next, the operation in the print mode, in which the present system equipped with the reader and the reader controller is used only as a printer, that is, via the printer controller 2103 A configuration for performing a printing operation will be described.

When the reader controller 106 is in the ready state, the reader controller 106 sets the gate unit 2207 and the signal control 220
8 is open. That is, the reader controller 10
6 is an engine control unit 2 using the input / output port 2203.
002: Ready state signal / PRDY of the image forming unit
Is checked, and if it is OK, the ready status signal / CRDY of the printer is set to the printer controller 2103 using the input / output port 2206.

Next, the printer controller 2103 performs communication for making various settings, and the reader controller 106 receives it using the serial communication controller 2205, and the received content is interpreted by the CPU 2209. According to the contents, the reader controller 10
6 performs various settings using the serial communication controller 2202. Engine control unit 2 for a series of commands
002 returns the corresponding status to the reader controller, and the reader controller
It is received using 202. The received content is CPU
The serial communication controller 2205 interprets the
Is used to communicate with the printer controller 2103.

Next, the print controller 2103 sends a print request / CP to the reader controller 106.
An RNT signal is generated, and in response, the reader controller 106 generates a print request / PPRNT signal to the engine control unit 2002. In response to this, the engine control unit 2002 returns a / PTOP signal after a predetermined time. This is passed through the gate control unit 2208,
/ CTOP signal as the printer controller 2103
To return. In the printer controller 2103, the / C
The vertical scanning direction is synchronized with the TOP signal, and
The YNC signal has passed through the gate control unit 2207 / CL
By synchronizing the SYNC signal in the horizontal direction and synchronizing the / CVDO signal with / CVCLK, the reader controller 106
Transfer to. In the reader controller, the selector 2201 is set so as to select the signal sent from the printer controller, and the signal sent from the printer controller is / PVCLK, / PVDO.
It is sent to the engine control unit 2002 as EN, / PVDO.

3.3 Difference between Print Mode Operation and Copy Mode Operation Next, the difference between the copy mode operation and the print mode operation described above will be described with respect to image transmission timing.

The print controller 2103 has an image memory (not shown), in which image data to be printed is stored in advance. Therefore, in the print mode, the print data / VDO is transmitted in response to the image leading end request signal / TOP signal sent from the engine control unit 2002.
The time required to output is the electrical delay time only.

On the other hand, in the copy mode, an original is read while moving the optical reading device 802 to obtain data to be used for printing. As shown in FIG.
From the state in which the reading device 802 is stopped to the state in which the reading device 802 moves at a high speed for reading a document, it takes time for acceleration, for example, about several hundred milliseconds. Therefore, if the engine control unit 2002 sends the image leading end request signal / TOP signal in the copy mode at the same timing as that signal in the print mode, the print image data / VDO reaches the engine only in the copy mode. Is delayed by several hundred milliseconds. To cope with this, there are the following two configurations. (1) Send out / TOP earlier in copying than in printing. (2) A separate signal (RSTART) is provided for the copy mode.

The configuration of the reader controller 106 for executing the above first configuration may be the one shown in FIG. 12. In the copy mode, the reader controller is set to / TO.
The movement of the document reading device is started by the P signal.

On the other hand, to execute the second configuration, the reader controller may have the configuration shown in FIG. That is, the image leading end request signal / PTOP sent from the engine control unit 2002 is a signal required only when the print controller performs printing, and need not be input to the interrupt controller of the reader controller. Further, the reading device movement start request signal / RSTART sent from the engine control unit 2002 is a signal required only in the copy mode, and need not be sent to the print controller.

3.4 Control for Setting Command As described above, the reader controller 1063 is provided between the printer controller 2103 and the engine control unit 2002.
Is connected, the printer controller 2103
Communication between the engine and the engine control unit 2002 is as follows.

When the reader controller 106 reads and outputs a document image using the engine control unit 2002 (copy mode), the printer controller 2103 issues a setting command, for example, a paper cassette change command, to the printer. The following describes the case where it is performed.

Prior to the description, a command issuing sequence in the case where the reader controller is not connected, that is, in the communication configuration described with reference to FIG. 4, will be described for comparison.

In this case, the printer controller 210
3 issues a paper feed cassette change command, waits for a response from the engine control unit 2002, determines the success of the command when the response comes, and ends a series of command issuing sequences. The engine control unit 2002 determines the content of the command when receiving the command from the printer controller, and notifies the printer controller 2103 of the successful command execution when the change is successful in the case of the paper cassette change command.

FIG. 15 is a flowchart showing a control procedure when the reader controller 106 is connected, that is, the control procedure of the reader controller 106 in the configuration shown in FIG. This control indicates the same control as the above-described processing of issuing a paper feed cassette change command between the printer controller 2103 and the engine control unit 2002.

FIG. 15B shows the printer controller 21.
11 is a flowchart showing a procedure for receiving a command from the MFP 03 and returning a status to the printer controller 2103. Reader controller 10
In step S6, a command is received by the serial communication controller 2205 from the printer controller 2103 via the / CCMD signal line shown in FIG. 11, and it is determined whether the command can be issued to the engine control unit 2002 as it is. For example, at present, the reader controller performs the copy mode operation so that the engine controller 2
When there is no command being executed for 002, the same command as that previously sent from the printer controller 2103 is sent to the engine control unit 2002, and the serial communication controller 2202 is sent to the engine control unit 2002. And issued via the signal line / PCMD.

On the other hand, for example, a paper cassette change command sent from the printer controller 2103 is sent to the engine control unit 2002 as it is, for example, when the reader controller 106 specifies a paper cassette and performs a copy operation. If the copy operation cannot be performed normally if issued, the engine control unit 2002
, The commands issued from the printer controller 2103 to the engine control unit 2002 are stored in the engine command queue that stores the commands in the order of issue. In this case, since a response to the command must be returned to the printer controller 2103, it is assumed that the command execution has been successfully performed from the reader controller 106, and the serial communication controller 2205 is used to return the command to the printer controller 2103 via the / CSTS signal line. I do.

FIG. 15A shows that the reader controller does not affect the state of the
3 shows a procedure when the command received from the engine control unit 3 becomes ready to be issued to the engine control unit 2002.

In such a state, the reader controller 106 uses the serial communication controller 2202 to send a signal line / P
It issues commands stored in the engine command queue through the CMD and waits for a response. Note that a command issued by the reader controller 106 itself is also transmitted to the engine control unit 2002 through the / PCMD signal line.
When the command execution is completed, a response is returned from the engine control unit 2002 via the / PSTS signal line. If the command execution is successful, the command is deleted from the engine command queue.

If it is found at this point that the engine has failed in executing the command, it is processed as an error occurrence state.

As described above, even when the reader controller is connected between the printer controller and the engine control unit, inconsistency in operation occurs when a normal command is issued from the printer controller 2103 to the engine control unit 2002. The command processing sequence can be executed without causing the error.

3.5 Control for State Change Signal Next, in a configuration in which a reader controller is interposed, the state change on the engine side, for example, the occurrence of some error state / engine control using PCCRT Processing performed when the information is transmitted from the unit 2002 to the reader controller 106 will be described.

In the case of a configuration in which the reader controller is connected therebetween, there is a possibility that the reader controller 106 and the printer controller 2103 have different desired changes in the state. For example, this is a case where a paper jam occurs during paper conveyance.

If a jam occurs while the engine (image forming unit) is performing a copy operation under the control of the reader controller 106, this state is a state that only the reader controller 106 wants to know. Since the printer controller 2103 is not the jam during the output of the printer controller 2103 itself, even if the printer controller 2103 is informed of this state, it cannot execute appropriate post-processing.

If a control system equivalent to the reader controller is to be mounted, since both controllers also have jam processing control software which should be provided by the other controller, they are redundantly mounted, resulting in design man-hours and quality evaluation. Therefore, a lot of waste occurs in the capacity of software.

Therefore, it is basically necessary to notify the printer controller 2103 in the print mode and notify the reader controller in the copy mode. However, even in the copy mode, the printer controller 2103 may obtain an engine state change signal in some cases. For example, it is necessary to notify the printer controller 2103 of information such as a change in the cassette size and the absence of paper. These do not strictly question the time from when the state change signal is issued by the engine control unit 2002 to when the processing is performed by each controller.

Therefore, in the present embodiment, the following processing is performed. That is, in the copy mode in which the reader controller 106 controls the engine control unit 2002, the state change signal / PCCRT notified from the engine control unit 2002 using the gate function of the control circuit 2208 is transmitted to the printer controller 2103.
, And only the reader controller receives it through the interrupt controller 2204.

At this time, the reader controller 106
Processing is performed according to the control procedure shown in FIG. That is, /
When the PCCRT signal becomes true, the reader controller 106 issues a command for acquiring a state change to the engine control unit 2002. After that, the returned status is checked to understand the content of the engine status change. Then, it is determined whether or not the content is a content to be notified also to the printer controller 2103. For example, a state change such as a change in the size of the sheet cassette is notified. If it is determined that the notification is to be made, a flag is set using the control circuit 2208, a state change signal / CCCRT is generated, and the printer controller 2103 is notified.

In the print mode in which the printer controller 2103 controls the engine control unit 2002, the gate function of the control circuit 2208 is released, and the state change signal / P notified from the engine control unit 2002 is released.
The CCRT is notified to the printer controller 2103 as a state change signal / CCCRT.

3.6 Control for Execution Command Next, control of the execution command will be described. For example,
Printer controller 2103 and reader controller 1
A description will be given of how the reader controller 106 performs control when the controller 06 simultaneously issues a use request to the engine control unit 2002.

FIG. 17 is a diagram showing the location and exchange of data when a print request is issued during a copy operation.

In FIG. 17, an engine control unit 2002
Receives the print data signal / PVDO sent from the reader controller 106, and forms an image based on the print data signal / PVDO. As described with reference to FIG. 9, the setting of the sheet feed cassette, the sheet discharge port, and the image forming mode is performed by the reader controller 106 and the engine controller 2002.
Has already been set by serial communication. Reference numeral 1301 denotes a buffer for these various setting values, in which values set by the reader controller 106 in the engine control unit 2002 and values set by the printer controller 2103 in the engine control unit 2002 are stored. Among the various setting values shown in the buffer 1301, the setting value for the reader stores the specified value described above.

Here, when a print request is issued from the printer controller 2103 during the copy operation, it is not preferable that the printout is performed by interrupting the copy operation from the viewpoint of the user's superior use. Therefore, the print request in this situation is postponed until the copy operation is completed. However, in this case, in response to / CCMD from the printer controller 2103, /
CSTS must be returned. So, buffer 1
Of the setting values in 301, only the setting value for the PDL from the printer is set in response to a request. If the setting value for the reader and the setting value for PDL are different,
The setting may be performed from the reader controller 106 to the engine control unit 2002 after the copy operation is completed and before the printer operation is started. Specifically, it is as follows.

During the copying operation, paper is fed from the upper cassette and discharged to the face-up discharge port. The image forming mode is also set to the color mode based on the determination that the document is in color. Suppose. Here, when a print request is issued from the printer controller 2103, the print execution itself is postponed, but various settings can be made. Here, it is assumed that the print request is a request for feeding paper from the upper cassette, discharging the paper to the face-down discharge port, and further outputting a monochrome image. Regarding the sheet cassette designation, both the reader controller 106 and the printer controller 2103 designate the upper cassette.
Therefore, even when the copy operation is completed and the operation is switched to the print operation, there is no need to issue a paper feed cassette designation command to the engine control unit 2002. Regarding the discharge port and the image forming mode, since the designation is different between the copy operation and the print operation, when the copy operation is completed, a command for specifying the discharge port and specifying the image formation mode is sent from the reader controller to the engine control unit 2002 again. Need to be issued.

As described above, the reader controller 106
Does not judge that the command from the printer controller 2103 is only to postpone execution of the command to the engine control unit 2002, but that the reader controller 106 has already set the command to the engine control unit 2002. Is determined such that duplicate settings are not made.

Next, a case where a copy request occurs during a printing operation will be described with reference to FIG. In this case, contrary to the case shown in FIG. 17, from the viewpoint of usability,
Even if the user presses the copy button, it is preferable that the copy operation can be executed in an interrupting manner rather than that the copy operation cannot be performed during the print operation.

In this case, the printer controller 2103
/ CVDO sent from is selected by the selector 2201,
/ PVDO to the engine control unit 2002. Assuming that the settings are exactly the same as those described with reference to FIG.
Assuming that the settings from the printer controller 2103 are the upper cassette, the face-down discharge port, and the black-and-white image mode, the engine control unit 2002 detects the end only when the / PPRNT signal from the printer controller 2103 becomes High (false). I don't know how many copies will be printed out. It is assumed here that the printer is about to print out four images.
If the copy operation request is not made from the reader by interruption, the engine control unit 200 operates as shown in the image timing shown in FIG.
2, two / PTOP signals are generated, and an image is sent from the printer controller 2103 to the engine control unit 2002 via the reader controller in response to the / PTOP signal.

It is assumed that an interrupt copy request for copying one color document is issued to the reader controller during the second printout. In this case, FIG.
9 will be described.

/ C from printer controller 2103
In response to the PRNT request, the reader controller 106
A PPRNT request is issued to the engine control unit 2002, and the / PTOP signal is supplied from the engine control unit 2002 to the print controller as a / CTOP signal via the reader controller. Thus, 1501
The print operation of the second image is executed at the timing 1502 and the first image shown in FIG.

Here, a case will be described in which the reader controller issues an interrupt copy request during the second printout operation. The reader controller generates a / CCCRT signal for the printer controller 2103.
This is not that the state of the engine has actually changed, but the reader requests the printer controller 2103 to open the engine in order to acquire the printer engine. The generation method uses the control unit 2208 as described above. In response to the / CCCRT signal, the printer controller 2103 issues a command for checking the status status of the engine, and the reader controller returns a status of "copying" to the printer controller 2103. Then, the printer controller 2103 changes the / CPRNT signal to Lo.
While keeping w (true), the engine detects that the copying operation is being performed, and continues to wait for the / CTOP signal to come. If not in a copy state, / CPRNT is Low
If / CTOP does not come with (true), a timeout error occurs after a certain period of time. In the case of a copy state, the printer controller 2103 releases the timeout and waits for the / CTOP signal forever. I do. This time sent from the engine control unit 2002 /
The PTOP signal is for performing a copy operation, and the reader controller uses the / PTOP signal. Further, as shown by the timing 1505, the / PTOP signal sent from the engine side is
103 is to be masked. The print data signal actually generated by the reader controller is the print data signal 1
506 only. After the completion of one interrupt copy, the mask of the / PTOP signal is removed again, and the / CTO signal is removed.
By sending P to the printer controller 2103, the image 15 from the printer controller 2103 is output.
03, 1504 can be output to the engine control unit 2002. According to the above description, the interruption copy operation during the print operation can be realized.

As described above, the printer controller 210
3 and the state of the reader controller 106, the reader controller determines and controls which printer engine is to be acquired, and at what timing a command is issued. On the other hand, requests from the two controllers can be realized.

3.7 Control for Setting Content Confirmation Command Next, control when the printer controller 2103 issues a setting content confirmation command will be described.

When the printer controller 2103 wants to confirm the state set in the engine control unit 2002, the printer controller 2103 issues a setting content confirmation command through / CCMD. The reader controller that has received it checks the setting value storage buffer shown in FIG.
If the content that the user wants to check is present in this buffer, the content is read out and notified to the printer controller 2103 via / CSTS. If the content is not in this buffer, the reader controller 106 issues a setting content confirmation command through / PCMD. The engine control unit 2002 reads the content, notifies the reader controller of the setting content via / PSTS,
The reader controller notifies the printer controller 2103 of the content via / CSTS.

4. Calibration The calibration in the printing system described above will be described.

The calibration according to the present embodiment is performed to maintain the density output characteristics in printing at a constant value. This calibration is performed in both the copy mode and the print mode described above, but as will be described later, the present invention is applied to a method of performing the calibration in the copy mode.

Before describing how to execute the calibration in the copy mode according to an embodiment of the present invention, the contents of the calibration in each of the copy mode and the print mode will be described.

4.1 Calibration in Copy Mode FIG. 20 is a block diagram mainly showing details of the image signal processing unit 902 (see FIG. 12 and the like) in the reader controller 106.

In the figure, reference numeral 3001 denotes a reader 101
Constituting the photoelectric conversion unit 104 in FIG.
4 shows a D sensor. That is, the main image signal processing unit 902
Is for performing image processing described below on data read by the reader 101 and generating print data used by the image forming unit 2003.

Reference numeral 3002 denotes a shading correction unit.
The reading characteristics of the reader 101 are corrected. An input masking unit 3003 corrects the light absorption characteristics of each color toner in the image forming unit. Reference numeral 3004 denotes a background removal section, which is black based on yellow (Y), magenta (M), and cyan (C) data obtained by the masking process.
The data of (K) is generated. Reference numeral 3005 denotes a direct mapping unit, and 3006 denotes a data sampling unit.

Reference numeral 3007 denotes an output γ correction unit for correcting the relationship between print data and density actually realized by toner in the image forming unit, and performing correction processing in a table form. The output γ correction unit 3007 is a process to be calibrated as described below, and the contents of the table are updated by the calibration.

Reference numeral 3008 denotes an output processing unit which performs a binarization process with dither pattern data to generate binary print data to be supplied to the laser driver of the image forming unit, as will be described later. Do. As described later, the dither pattern has two patterns, one that emphasizes gradation in print output and the other that emphasizes resolution. The dither pattern depends on the type of image to be printed or the setting of the user. , Selectively used. More specifically, the pattern emphasizing the gradation is a pattern for performing a binarization process for lowering the resolution of an image or the like that is a target of the binarization process. In the embodiment, the pattern is a pattern for performing a binarization process for maintaining the resolution of an image or the like to be binarized. It is needless to say that the pattern emphasizing the resolution may be a pattern for performing a process for further increasing the resolution.

The output processing unit 3008 described above performs a binarization process in response to the fact that the laser used in the image forming unit of this embodiment can only be turned on and off. is there. However, if the laser to be used is of the pulse width modulation type, for example, quantization processing such as binarization is not required. In this case, for example, 8-bit print data is directly input to the pulse width modulation circuit, a pulse width signal modulated according to the print data is generated using a triangular wave and a comparator, and the pulse width signal is input to the laser driver. Thus, gradation printing is performed.
Therefore, in the case of this configuration, as a process of setting the resolution of each print image with emphasis on gradation and resolution, two triangular waves having different periods are prepared, and are selectively selected according to the type of image to be printed. The processing for setting the resolution (density) of the pulse width signal using a triangular wave corresponds to the above.

Reference numeral 3009 denotes a PG (pattern generator)
And outputs data of a predetermined patch pattern at the time of calibration.

The calibration based on the above configuration is performed as follows.

In the calibration, first, the PG30
From 09, a pattern consisting of a plurality of patches of a predetermined density is output. Then, the pattern data is subjected to the processing of direct mapping 3005 and output processing 3008
To enter. In calibration, the γ correction unit 3007 is a processing unit to be directly subjected to calibration, and is set so that the correction processing is not performed.

Next, in output processing 3008, binarization processing is performed using dither pattern data set for emphasis on gradation and resolution, and the binary patch pattern data is output to the engine controller 2002. As will be described later, the calibration is performed on both or one of the dither pattern data set for each of the tone emphasis and the resolution emphasis. That is, when performing both of the dither pattern data, the calibration process such as the print output of the patch pattern is performed twice.

FIG. 21 is a diagram showing an example of a patch pattern printed and output based on the patch pattern data obtained as described above. Next, the sheet on which this pattern is printed is placed on a document table of the reader 101 and read. The read data is input to the image signal processing unit 902 shown in FIG.
02 and the like are performed, and the data is sampled by the data sampling unit 3006.

The sampling result is sent to the CPU 2209.
And calibration data is generated. That is, the difference between the input density data (print data) input for printing each patch and the output density data obtained by the above sampling is obtained, and based on this, the input of the patch whose output density data is ideal is obtained. Data for correcting the input density data is generated as calibration data so as to be density data.

More specifically, it is assumed that the input / output characteristics before calibration, that is, when the patch is output, indicated by the sampled data are plotted by ● as shown in FIG. In this case, since the actual output density is lower than the ideal output density data for the input data, correction data for increasing the input data so as to obtain the ideal density is required. create. The calibration data obtained in this way is output to the output γ correction unit 3007 by γ.
This is set as the contents of the correction table.

4.2 Calibration in Print Mode Calibration when printing is performed using the print controller 2103 will be described.

FIG. 23 shows the printer controller 2103.
FIG. 2 is a block diagram illustrating a configuration of an image processing unit provided in the image processing unit.

In the figure, reference numeral 3101 denotes the host device 21.
Reference numeral 3102 denotes an input I / F with an external device such as an external device 04. Reference numeral 3103 denotes an object generation unit, and reference numeral 3104 denotes an object buffer. Reference numeral 3105 denotes a rendering unit. Reference numeral 3106 denotes a band buffer for storing, for example, rasterized data, which has been binarized by the dither processing unit 3109. Also, as for the dither processing unit 31093109, similarly to the above, a dither pattern emphasizing the resolution and a dither pattern emphasizing the gradation are prepared. Reference numeral 3107 denotes an output I / F to the reader controller 106. Reference numeral 3108 denotes a data correction unit that performs processing including gamma correction. 3110 is a CPU, 3111 is a communication controller, 3112 is a PG
Parts are shown.

The creation of calibration data with the above configuration is almost the same as in the copy mode described above.

First, the PG section 3112 outputs a pattern composed of a plurality of predetermined density patches. Then, predetermined image processing is performed, and output to the engine controller 2002 via the reader controller 106 to print a patch pattern as shown in FIG. 21 on a sheet.

The data read by the reader 101 is sampled by the data sampling unit 3006 in the image signal processing unit 902 of the reader controller. Based on this sampling data, calibration data is created in the same manner as described above.

The created calibration data is sent from the reader controller 106 to the printer controller 2103. Printer controller 2103
The CPU 3110 sets the received calibration data as a γ correction table of the data correction unit 3108.

As described above, the contents of the calibration data sent from the reader controller to the printer controller may be the contents of the γ correction table itself. Specifically, data of 256 gradations for each of three or four colors is sent. Further, the creation of the γ correction table itself may of course be performed by the printer controller. In that case, the read data is transmitted as it is. 3 data for the number of patches
It is the data amount for the color or four colors. Further, a configuration may be adopted in which a difference between read data and ideal data is transmitted as calibration data.

4.3 Calibration During Printing The calibration described in the above sections 4.1 and 4.2 is calibration performed as an initial process before printing (copying) starts, that is, during non-printing operation. .

In this embodiment, continuous printing (copying) is performed.
When the environmental temperature and the elapsed time satisfy predetermined conditions, the printing operation is temporarily interrupted regardless of the printing operation, and the calibration is automatically performed. This makes it possible to suppress a change in print density due to a change in conditions such as the environmental temperature.

In this embodiment, patch pattern data is generated in the same manner using the image signal processing unit 902 shown in FIG. 20, and a visible image of the patch is formed by toner on the intermediate transfer member 405 shown in FIG. Then, it is
(See FIG. 6), and based on the reading result, the image signal processing unit 90 is used as in the copy mode.
In step 2, calibration can be performed.

The location where the patch is formed does not need to be on the intermediate transfer member, but may be on a transfer material (paper). However, considering the mechanical configuration, the rotating intermediate transfer member is more preferable than the transferred transfer material. In the case of a configuration having no intermediate transfer member, a method may be used in which the density of a patch based on a latent image on a photosensitive drum is obtained by a potential sensor.

When calibration is performed in the printer engine, it is necessary to newly add a sensor as described above. However, since the reading sensor is not required for other uses, it is necessary to separately provide the reading sensor only for calibration. Therefore, increasing the number and accuracy of the sensors requires a lot of cost. Therefore, in the present embodiment, the present invention is implemented by providing one optical sensor using a general-purpose phototransistor instead of an expensive image reading sensor. The sensor prints patches in a line at a position that can be read by the sensor when the rotating body rotates on the rotating surface of the intermediate transfer body. The patch size is 10 mm square and the number of patches is 32 from the reading range of the reading sensor. FIG. 24 shows a state where the intermediate transfer member on which the patch is formed is spread on a plane. Here, 401 is a patch, and 402 is an intermediate transfer member.

<Embodiment of Calibration> The printing system according to the present embodiment described above can selectively perform image processing emphasizing gradation and image processing emphasizing resolution in printing. The calibration is basically configured to be performed for each of the two types of image processing. in this case,
Calibration before the start of printing and calibration during printing are performed for every two image processes.

However, since the execution of the calibration basically requires a lot of time, performing the calibration for all the image processing before the start of printing and during printing is a great amount of time. Will be done. Therefore, in the present embodiment, it is possible to maintain a constant print density in a short time (calibration) by utilizing the characteristics of each calibration.

That is, since the calibration before the start of printing involves the operation of the user placing the sheet on which the patch pattern is printed on the platen of the reader, extra time is required. . For this reason, the calibration before the start of printing is performed only with respect to one image processing, in this embodiment, image processing that emphasizes gradation. On the other hand, calibration performed during printing is performed for both image processing that emphasizes gradation and image processing that emphasizes resolution.

According to the above configuration, for example, when a relatively large amount of printing or copying is performed, calibration during printing is frequently performed. In this case, the calibration is performed by a user operation. By not requiring, the time required for calibration as a whole can be reduced, and
Calibration can be performed without imposing too much load on the user.

In the above-described embodiment, the calibration performed before the start of printing is related to image processing that emphasizes gradation, but the present invention is not limited to this. Depending on the type of image to be printed by the printing system and the user's settings, the calibration performed before the start of printing may be related to image processing that emphasizes resolution. Further, the types of image processing are not limited to two types as described above, and may be three or more types. In this case, the calibration performed during the non-printing operation and during the printing can be set according to the type of image to be printed by the printing system in a relatively large number, as described above.

<Other Embodiments> As described above, the present invention is applied to a system constituted by a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), and a single device (for example, (A copying machine, a facsimile machine).

Further, software for realizing the functions of the above-described embodiment is provided to an apparatus or a computer in a system connected to the various devices so as to operate the various devices so as to realize the functions of the above-described embodiment. The present invention also includes a program code supplied and executed by operating the various devices according to a stored program in a computer (CPU or MPU) of the system or apparatus.

In this case, the program code of the software implements the functions of the above-described embodiment, and the program code itself and means for supplying the program code to the computer, for example, the program code The stored storage medium constitutes the present invention.

Examples of a storage medium for storing such a program code include a floppy (registered trademark) disk, a hard disk, an optical disk, a magneto-optical disk, and a CD-R.
An OM, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the supplied program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer, or another program. Needless to say, the program code is included in the embodiment of the present invention even when the functions of the above-described embodiment are realized in cooperation with application software or the like.

Further, the supplied program code is stored in a memory provided in a function expansion board of the computer or a function expansion unit connected to the computer, and then, based on the instruction of the program code, the function expansion board or the function expansion unit. It is needless to say that the present invention includes a case where the CPU or the like provided in the first embodiment performs a part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0148]

As is apparent from the above description, according to the present invention, the execution of the first calibration means and the second calibration means for a plurality of image processings is performed by the first calibration means. Since the calibration is performed with respect to a smaller number of image processes than the calibration-related image processes performed by the second calibration means, the first calibration requires a relatively long time to execute, and the corresponding image processing is performed. If properly set, it is possible to reduce the time for the calibration performed as a whole, while minimizing the deterioration of the printing characteristics related to the image processing.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a printing system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration in a case where the configuration shown in FIG. 1 is used only as a printer without mounting a reader controller.

FIG. 3 is a block diagram illustrating a printing system configured by connecting the printer via a network.

4 is a diagram showing signals transmitted and received among a printer controller, rollers, and an engine control unit in the configuration shown in FIG. 2;

FIG. 5 is a diagram showing the types of the signals.

FIG. 6 is a diagram showing a mechanical configuration of a printer in the printing system.

FIG. 7 is a timing chart of a signal relating to printing.

FIG. 8 is a timing chart of serial communication signals among the various signals.

FIG. 9 is a diagram illustrating a state of communication during a printing operation between the printer controller and the engine control unit.

FIG. 10 is a diagram illustrating a configuration when a reader is mounted on a printer of the printing system.

FIG. 11 is a diagram showing signal connections between the reader controller, a printer controller, and an engine control unit when the reader controller is mounted.

FIG. 12 is a block diagram showing a detailed configuration of the reader controller.

FIG. 13 is a diagram illustrating a difference in signal transmission timing between a copy mode and a print mode.

FIG. 14 is a block diagram showing a detailed configuration according to another example of the reader controller.

FIGS. 15A and 15B are flowcharts showing a communication sequence when a reader controller is mounted.

FIG. 16 shows signals / when a reader controller is attached.
It is a flowchart which shows the process regarding the state change in CCRT.

FIG. 17 is a diagram illustrating a process of a print request during a copy operation in the printing system.

FIG. 18 is a diagram illustrating a process of a print request during a printing operation in the printing system.

FIG. 19 is a timing chart of each signal at the time of interrupt copying in the printing system.

FIG. 20 is a block diagram illustrating a detailed configuration of an image signal processing unit provided in the reader controller.

FIG. 21 is a diagram showing a patch pattern output by calibration in the printing system.

FIG. 22 is a diagram illustrating a process of creating the calibration data.

FIG. 23 is a block diagram illustrating a detailed configuration of an image signal processing unit provided in the printer controller.

FIG. 24 is a diagram showing a patch pattern output in calibration during printing in the printing system.

[Explanation of symbols]

 101 reader 106 reader controller 902 image signal processing unit 1301 set value buffer 2001 printer 2103 printer controller 2002 engine control unit (engine controller) 2104 host computer 2201 selector 2207 gate 2208 control circuit 2209 CPU 3006 data sampling 3007 gamma correction unit 3008 output processing unit 3108 Data correction unit 3112 PG unit

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2C061 AP04 AQ06 KK02 KK04 KK25 2C262 AA04 AA24 AA26 AB13 AB20 AC04 BB01 BB06 BB27 BB30 BB36 BC01 BC10 EA02 EA04 EA06 FA13 GA42 5C077 LL12 LL19 MM27 MP01 PP

Claims (17)

[Claims] 1. A printing apparatus capable of performing printing based on print data generated by a plurality of image processes having different processing modes, wherein a printing characteristic of the printing device is determined for each of the plurality of image processes. A first calibration unit capable of performing a constant calibration; and a calibration capable of performing a calibration for maintaining a constant printing characteristic of the printing apparatus with respect to each of the plurality of image processes. A first calibration unit, a second calibration unit having a different aspect of the calibration, and the second calibration unit performs calibration for each of the plurality of image processes;
A control unit that controls the first calibration unit to perform calibration on a smaller number of image processes than the image processes related to calibration performed by the second calibration unit among the plurality of image processes; A printing device, comprising: 2. The method according to claim 1, wherein the first calibration means includes:
2. The calibration pattern according to claim 1, wherein a patch pattern is printed on a sheet, and calibration data is created based on data read by setting the sheet on a reading device through a user operation. Printing device. 3. The first calibration means,
3. The printing apparatus according to claim 1, wherein the printing is performed during a non-printing operation. 4. The second calibration means,
4. The printing method according to claim 1, wherein a patch pattern is formed on an image forming medium in the apparatus, and calibration data is created based on the pattern read by a reading device. apparatus. 5. The second calibration means,
5. The printing apparatus according to claim 1, wherein the printing is performed during a printing operation. 6. The printing apparatus according to claim 4, wherein the printing apparatus performs printing by an electrophotographic method, and the patch pattern is a visible image. 7. The printing apparatus according to claim 4, wherein the printing apparatus performs printing by an electrophotographic method, and the patch pattern is a latent image. 8. The plurality of image processes include an image process for performing a process emphasizing gradation in printing and an image process for performing a process emphasizing a resolution in printing. 8. The image processing apparatus according to claim 1, wherein a calibration unit controls the image processing in which the gradation is emphasized.
The printing device according to any one of the above. 9. A method for calibrating a printing apparatus capable of performing printing based on print data generated by a plurality of image processes having different processing modes, wherein the plurality of image processes are performed with respect to each of the plurality of image processes. A first calibration unit capable of performing a calibration for maintaining the printing characteristics of the printing apparatus, and a calibration for maintaining the printing characteristics of the printing apparatus for each of the plurality of image processes. Wherein the first calibration means and a second calibration means having a different aspect of the calibration are provided, and wherein the second calibration means Calibrate for each,
The first calibration means controls to perform calibration on a smaller number of image processings of the plurality of image processings than the image processing on the calibration performed by the second calibration means. A calibration method, characterized in that: 10. The first calibration means prints a patch pattern on a sheet of paper, and sets calibration data based on data read by setting the sheet on a reading device through a user operation. 10. The calibration method according to claim 9, wherein 11. The calibration method according to claim 9, wherein the first calibration unit is performed during a non-printing operation. 12. The apparatus according to claim 1, wherein the second calibration unit forms a patch pattern on an image forming medium in the apparatus, and creates calibration data based on the data read by the reading apparatus. The calibration method according to any one of claims 9 to 11, wherein 13. The apparatus according to claim 9, wherein said second calibration means is performed during a printing operation.
13. The calibration method according to any one of claims 12 to 12. 14. The calibration method according to claim 12, wherein the printing device performs printing by an electrophotographic method, and the patch pattern is a visible image. 15. The calibration method according to claim 12, wherein the printing device performs printing by an electrophotographic method, and the patch pattern is a latent image. 16. The plurality of image processes include an image process for performing a process emphasizing gradation in printing and an image process for performing a process emphasizing a resolution in printing. 16. The calibration method according to claim 9, wherein a calibration unit controls to perform calibration with respect to the image processing that emphasizes the gradation. 17. A program for executing a calibration of a printing apparatus capable of performing printing based on respective print data generated by a plurality of image processes having different processing modes, the program comprising: A first calibration unit capable of performing calibration for maintaining the printing characteristics of the printing apparatus constant for each process, and for maintaining the printing characteristics of the printing apparatus constant for each of the plurality of image processes; A calibration capable of performing a calibration, wherein the first calibration means and a second calibration means having a different aspect of the calibration are provided, and the second calibration means Calibration for each of the plurality of image processes. It performs a down,
The first calibration means controls to perform calibration on a smaller number of image processings of the plurality of image processings than the image processing on the calibration performed by the second calibration means. A program having code means for processing.