JPS61265966A - Digital image forming device - Google Patents

Abstract

PURPOSE:To speed up image forming processing by storing image data on plural originals specified by the control of a write control means in an image memory when a synthesizing mode is selected and permitting an image forming means to form and out-put plural original images on a sheet of paper in accordance with contents in the image memory. CONSTITUTION:The image synthesizing mode, which synthesizes and forms plural original images on a sheet of paper, is selected by depressing a synthesizing mode selecting key on the 1st operational panel. For instance, it reads sequentially images of the originals P1-P4 one by one. The images read out in such a way are transferred to an image bus through a scanner interface 409, and are written in the 1st color pate memory 403 being an image memory. Contents in the image memory 403 are transferred to the printing control part of an LBP unit through a laser beam printer LBP interface 410, and plural original images can be formed on one sheet by one image forming action.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a digital image forming apparatus that digitally reads an image of a document, stores it in an image memory, and forms an image on paper based on the contents of the image memory. Regarding.

[Technical backstory of the invention and its problems] This type of device optically combines the image of a document, converts it into a digital signal, and uses a laser beam to drive the image onto the photoreceptor based on the content stored in the image memory. An example of such a printer is a laser printer that forms a latent image on a sheet of paper and forms an image on a sheet of paper using electrophotography.

In this type of apparatus, it is normal to read a document one sheet at a time and copy the image onto one sheet of paper.

By the way, if an image editing function was provided that could form and output images from multiple documents onto a single sheet of paper, the image forming operation would only be required once, speeding up processing and reducing paper consumption. This makes it possible to reduce maintenance costs.

However, until now, a digital image forming apparatus capable of performing the above-described image editing has not been provided.

[Object of the Invention] The present invention has been made in view of the above circumstances, and has a function of forming and outputting images of multiple documents on one sheet of paper, and has a function of forming images on one sheet of paper. It is an object of the present invention to provide a digital image forming apparatus that can vary the number of original sheets to be printed.

[Summary of the Invention] The present invention for achieving the above object has a composition mode selection means for selecting an image forming operation for combining and forming a plurality of original images on one sheet of paper; and a number of originals input means for inputting the number of originals on which images are to be formed, and when the composition mode is selected, the image data of the specified plurality of originals is stored in the image memory under the control of the write control means. The image forming means is characterized in that it forms and outputs a plurality of original images on one sheet of paper based on the contents of the image memory.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. This embodiment relates to a two-color laser printer equipped with an automatic document feeder.

FIG. 1 shows the external appearance of the apparatus of this embodiment, which includes an automatic document feeder (hereinafter abbreviated as ADF) 1, a scanner unit 110, which will be described later. A printer main body 100 consisting of a laser print unit (hereinafter abbreviated as LBP unit) 300;
It is composed of a control unit 400.

The ADF 1 includes a document cover 2 incorporating a document transport section 30, which will be described later, a document supply section 3, and a document tray 4. The document cover 2 is rotatable in the direction of the arrow shown in the figure by operating the handle portion 2A, so that the document can be placed directly on the exposure glass when the automatic document feed function is not used. . Further, on the upper surface of the document cover 2, a liquid crystal display (hereinafter referred to as LC) displays an image read by a scanner unit 110, which will be described later.
(abbreviated as D) 5 and a first operation panel 6 for inputting information for image editing are arranged.

The printer main body 100 includes a second operation panel 101 on the top side for inputting print information, and -
An upper cassette 32) and a lower cassette 322 for feeding paper are removably arranged on one side, and a paper discharge tray 344 is provided on the other side.

In this embodiment, the ADF1. Printer main body 10
0 and the control unit 400 are integrally configured,
Since we do not use a method in which each component is connected as an independent unit using cables, image buses, etc., the installation space for each component is minimized, and side panels etc. can be used in common, making the device lightweight. It is possible to achieve a reduction in cost and cost.

Here, we will discuss the second main control block of the device of this embodiment.
This will be briefly explained with reference to the drawings. In Figure 2, the CPU
Reference numeral 401 controls the control of this laser printer, and this CPLJ pass line includes LCD interfaces 4o7. Serial interface 408. A scanner interface 409 and an LBP interface 410 are connected to each other. Further, the LCD interface 4
07. The scanner interface 409 and the LBP interface 410 are connected to the first color and second color image data bus lines, respectively. Further, as image processing of the first color image data outputted via the scanner interface 409, a first color page memory 403 and a first color page memory address controller 4
A second color page memory 405 and a second color page memory address controller 406 are provided for image processing of second color image data.

Then, when image editing information is input from the first operation panel 6, the first . The second color page memory address controller 404,406 is connected to the first color page memory address controller 404,406. Reading and writing of image data in the second color page memories 403 and 405 are controlled to perform various image editing operations.

Next, details of each of the above parts will be explained.

First, the details of the ADF 1 are shown in FIGS. 3, 4 (A), (
This will be explained with reference to B).

In FIG. 3, the original document supplying section 3 of the ADF1 is composed of a document placing table 10 and a separation feeding section 15. As shown in FIG.

As shown in FIG. 4(A), the document mounting table 10 has document guides 11 and 11 that are movable according to the width of various documents (for example, A5.85.84 size). The document guides 11.11 each have a rack 12.12 inside the document table 10. In addition, the document placement table 1
A pinion 13 is rotatably attached to the center line in the width direction of the document placed on the paper. this gonion 1
3 is adapted to engage with both said racks 12.12. Therefore, when one document guide 11 is moved to match the document width, the other document guide 11 is also moved by the same distance due to the action of both racks 12.12 and the common pinion 13, and both document guides 11 is the center 11L
It always moves symmetrically. Further, a bent portion 12A is formed on one side of one of the racks 12 by being bent downward, and the moving path of this bent portion 12A includes various types of movement as shown in FIGS. 4(A) and 4(B). A plurality of switches 14A are provided at positions corresponding to the document width.

A document width detection switch 14 is provided, which is formed by disposing 14B... Then, the plurality of switches 14A,
The width of the original placed on the original placing table 10 is detected from the combination of ON and OFF states of 14B, . . . .

The separating and feeding unit 15 sequentially separates and feeds the originals stacked on the original document mounting table 10 one by one. A document presence/absence detection switch 16 is provided in the separating and feeding section 15, which comes into contact with the upper surface of the stacked documents and is displaced according to the number of documents. Further, there are provided a stopper 17 that comes into contact with the lower surface of the document and presses the document upward, and a feed roller 18 that is disposed opposite to the stopper 17 and that frictionally sends out the uppermost layer of the document. The separation feed roller 19, which is a pair of rollers, separates a plurality of documents fed between the pair of rollers and feeds them one by one. The document supplied by the separation feed roller 19 is sent out with the supply timing controlled by the registration rollers 20. In addition, registration roller 20
A document detection switch 2) is provided at the rear stage, and this document detection switch 2) counts the number of documents passing by and detects the length of the document being passed. Therefore, the vertical and horizontal sizes of the document are automatically detected by the document width detection switch 14 and the document detection switch 2).

The document transport section 30 built into the document cover 2 includes:
It is composed of an endless belt that moves on the exposure glass 111 and rollers that drive the belt, and the document that has been separated and fed from the separation and feeding section 15 is conveyed along the exposure lath 111 to a predetermined document stopping position. It is something. The separating and feeding section 15 and the document conveying section 30 convey one sheet of the document onto the exposure glass 111, and after the exposure is completed, the document is transferred to the printer main body 1.
In synchronization with the processing timing at 00, this document is ejected and conveyed to the document tray 4, and the next document is driven to be conveyed.

Further, on the upper surface of the document cover 2, the LCD 5 and the first operation panel 6 are provided.

By providing the LCD 5, which is an example of a display device that displays images read by the scanner unit 110, it is possible to check whether the image to be copied is accurately read after reading the image and before starting copying the image. can be visually recognized, and unnecessary copying operations can be prevented. Therefore, it is possible to check whether the image is tilted or whether the document reading area (described later) has been specified correctly before copying. It is possible to significantly reduce wasted paper consumption compared to conventional paper. Note that such a display device is not limited to the LCD 5, and various display methods can be adopted. Further, if it is arranged on the upper surface of the document cover 2 as in this embodiment, the operator can easily see the screen of the LCD 5 and confirm the read image. in this way,
When disposed on the upper surface of the document cover 2, a flat type display is preferable, and in addition to the LCD 5, an LED display or a plasma display may be used.

Next, the scanner unit 110 in the printer main body 100 will be explained with reference to FIGS. 3, 5, and 6. The scanner unit 110 performs exposure scanning on the original on the exposure glass 111 and inputs reflected light from the original into the photoelectric conversion section 120 . That is, as shown in FIG. 3, the exposure light source 112 and the first mirror 113 are attached to the first carriage 116, and the second mirror 114 and the third mirror 115 are attached to the second
It is attached to a carriage 117 and is capable of reciprocating along a guide shaft 118 in the direction of the arrow in the figure. Then, the light reflected from the original that is irradiated by the light source 112 and scanned over the entire exposure area of the original is focused by a lens 119 and incident on a CCD (charge coupled device) 12) of a photoelectric conversion unit 120, and is converted into image data. It is now converted to .

Here, the control block of this scanner unit 110 will be explained with reference to FIG. The scanner unit CPU 130 is in charge of controlling the scanner unit 110, and the program memory 131 connected to its pass line stores the execution procedure in the scanner unit 110. The carriage drive control section 132 drives and controls a stepping motor and the like to drive the first. second carriage 1
16 and 117, the speed of which is variable according to the enlargement/reduction mode signal from the scanner CPU 130. This first. Second carriage 116
．． By making the moving speed of the scanner 117 variable, the density in the feeding direction (sub-scanning direction) of the document can be made variable, allowing the image to be enlarged or reduced. The light source 111m section 133 drives the exposure light source 112 to emit light while the document is being read. ADFυ1'@ section 134 is the ADFI
It also transmits the document size to the CPU 130 based on the outputs of the document width detection switch 14 and the document detection switch 2), which is used to select the document reading area. . Also,
When no original remains based on the output of the original presence/absence detection switch 16, the scanner operation is terminated.

The binarization processing control unit 135 outputs a timing signal necessary for data reading to the photoelectric conversion unit 120,
Further, the digital data of 6 bits per dot outputted from the photoelectric conversion section 120 is subjected to binarization processing.

2) The processed image data is sent to the scanner interface 409 via the main control unit interface 136, and the first. It will be transmitted to the second color image data bus. The photoelectric conversion unit 120 includes the CCD 12), an amplifier 122 that amplifies the output thereof, and an A/D converter 123 that performs analog-to-digital conversion.
It is composed of. Then, the light emitted from the light source 112 and reflected by the first to third mirrors 113, 114, and 115 enters the CCD 12) through the lens 119, and the charges accumulated in the CCD 12) are transferred to the amplifier 122.
The signal is amplified by the A/D converter 123 and digitally converted by the A/D converter 123. Note that the output of the A/D converter 123 is, for example, 6 bits/dot. Further, in this photoelectric conversion section 120, the density in the sub-scanning direction is variable depending on the enlargement/reduction mode, whereas the clock speed corresponding to each dot is constant, and the density in the main scanning direction is variable depending on the enlargement/reduction mode. The density (corresponding to the width direction) is also constant (for example, 16 pieces/tm
).

Note that enlargement and reduction of the image in the main scanning direction will be described later. Further, main timing signals during the original m reading operation in this scanner unit 110 are shown in FIG. In the figure, rH8YNOJ is a synchronization signal for each line in the D1 scanning direction, and rDATJ indicates data. For example, during reading using eight data buses, binarized data is output in units of eight pits. rsTBOJ is a strobe signal of the rDATJ, and rVsYNOJ indicates that the sub-scanning direction is in the document reading area.

Next, the LBP unit 300 will be explained. In FIG. 3, reference numeral 301 is a photoreceptor for recording information with a laser beam, and around this photoreceptor 301, first chargers 302. First developer 303. Second charger 30
4. Second developer 305. A static elimination lamp 306 and a transfer charger 307 for increasing peeling efficiency. A peeling charger 308, a cleaning device H3O9, etc. are arranged.

Further, 310 is a laser scanner unit for scanning, modulating, and recording two laser beams a and b on the photoreceptor 301. The laser beam a emitted from the laser scanner unit 310 is reflected by a first reflecting mirror 311 and is directed from almost directly above the photoreceptor 301 to the first charger 302 and the first developer 303. The photoreceptor 301 is irradiated with a first exposure section 350 between the two. On the other hand, the laser beam b is the second one.
reflected by third reflecting mirrors 312 and 323, respectively,
The light is irradiated onto the photoreceptor 301 at a second exposure section 351 between the second charger 304 and the second developer 305 .

As shown in FIG. 7, the laser scanner unit 310 includes a first. a second laser diode 314,315; The laser beams a and b emitted from the second laser diode 314 and 315 are connected to collimator lenses 316 and 317 that make the laser beams a and b parallel beams, respectively, and are arranged at right angles so that the optical path of the laser beam a is parallel to the laser beam b. A bending prism 318 and a polygon mirror 31 that scans the laser beams a and b, respectively.
9, and an f/θ lens 320 disposed after the polygon mirror 319 as shown in FIG.

Then, when the laser drive circuit (not shown) operates, the first . Turn on the emission of laser beams a and b from the second laser diodes 314 and 315.

OFF and the amount of light are controlled i, and these laser beams a and b are irradiated onto one surface of a polygon mirror 319 via collimator lenses 316, 317 and a prism 318, where they are scanned in the main scanning direction. Thereafter, the laser beams a and b pass through the f/theta lens 320 to the first reflecting mirror 311 or the second . Third reflective mirror 31
2.313, and exposes the surface of the photoreceptor 301 to form an electrostatic latent image. This electrostatic latent image includes the first image. Developers of different colors are supplied by the second developing devices 303 and 305 and are visualized (details of this operation will be described later), onto the paper fed from the upper cassette 32) or the lower cassette 322. This image is then transferred.

Here, the arrangement of the exposure section with respect to the photoreceptor 301 will be explained. Since the device of this embodiment is a two-color laser printer, there are first and second laser printers in two locations. A second exposure section 350, 351 is provided. The angle θ between the direction of beam incidence on the photoconductor 301 to the first exposure section 350 and the direction of beam incidence on the photoconductor 301 to the second exposure section 351 is
(See FIG. 3) is set at an acute angle. Second exposure sections 350 and 351 are arranged. The reason for this arrangement is as follows. That is, since various parts must be arranged around the photoreceptor 301 as described above, the first. If the second exposure units 350 and 351 are arranged far apart (if the beam intersection angle θ is an obtuse angle), the space for arranging other members will be narrowed. For this,
The drum diameter of the photoreceptor 301 must be increased to secure space, resulting in a larger device. Therefore, in order to effectively utilize the space around the photoreceptor 301, the arrangement as in this embodiment is preferable. Furthermore, by arranging it in this way, the first. The second developing devices 303 and 305 can be configured to have substantially the same shape, and costs can be reduced by using common parts. In addition, in order to develop the second color, after the development is performed in the first developer 303, the second color is developed.
Although it is necessary to perform recharging using the charger 304, it is preferable to perform recharging as soon as possible after the first color development. Therefore, the arrangement of the exposure portions according to this embodiment is advantageous in that recharging can be performed quickly.

Furthermore, since the laser beams a and b must have the same optical path length, the first. By arranging the second exposure sections close to each other, it becomes easy to design such optical path lengths to be the same. Also, the data of the first color is exposed,
When printing the second color data in the vicinity of the developed area, the exposed area of the first color data on the photoreceptor 301 is printed in the 2i-th!
The time difference Δt during this time is determined by the angle θ and the angular velocity of the photoreceptor ω[deQ/S
ec], Δ becomes -θ/ω[5ec). Therefore, in order to reduce the time difference Δt, it is advantageous to reduce θ.

Next, this first. It is preferable that the second exposure portions 350 and 351 be provided in the upper half circumferential area A of the photoreceptor 301, as shown in FIG. 8(A). The reason for this is that the transfer charger 307, which is placed at a position facing the exposure section, can be placed below the photoreceptor 301. In this way, the paper onto which the image is transferred can be transported using its own weight, and the structure of the transport mechanism can be simplified.

If the exposure section is arranged in the lower half of the photoreceptor 301, the transfer charger, etc. will be arranged in the upper half of the photoreceptor 301, and in this case, the paper must be conveyed while being held by a belt or the like. However, such a configuration is very difficult and also complicated, which is undesirable. Next, by arranging the exposure section in the upper half of the photoreceptor 301, the first reflecting mirror 311 as shown in FIG.
The m-plane of can be directed downward. Therefore, dust etc. will not adhere to the mirror surface due to its own weight. It is also advantageous in this respect, since dust adhesion to the mirror surface has a significant effect on image quality. If the exposure section is placed on the lower half of the photoconductor 301, the mirror surface of the reflection mirror 352 must face upward as shown in FIG. This is complicated and undesirable.

Next, a paper feeding system and a paper ejection system will be explained with reference to FIG.

The upper set 32) includes an upper paper feed roller 323 for taking out sheets of paper one by one from the cassette, an upper paper out switch 324 for detecting that there is no paper left in the cassette, and an upper paper out switch 324 for detecting that there is no paper left in the cassette. It has an upper cassette size detection switch 325 that detects the paper size. Similarly, the lower cassette 322 also has a lower paper feed roller 326. A lower paper out switch 327 and a lower cassette size detection switch 328 are provided.

Further, above the upper cassette 32), there is provided a manual feed guide 330 into which paper can be inserted manually, and a manual feed switch 331 detects the paper inserted through the manual feed guide 330, and the insertion is confirmed by this switch. A manual paper feed roller 332 for conveying paper is arranged.

This upper cassette 32). Registration rollers 340 are arranged at the forward end of the conveyance path for sheets fed from the lower cassette 322 or the manual feed guide 330. The registration roller 340 synchronizes the image developed on the photoreceptor 301 with the paper, and sends the paper to the transfer charger 307. This transfer charger 30
The paper on which the image has been transferred in step 7 is transferred to the peeling charger 30.
8 and is discharged forward by the suction belt 341.
Furthermore, after the image is fixed by heat and pressure in a fixing device 342, it is delivered to the paper ejection tray 344 by a paper ejection roller 343.

Next, the two-color stamp year using the LOP unit 300 will be described.

The process of a two-color laser printer is to form a two-color toner image on the photoreceptor 301 during one rotation of the photoreceptor 301 and transfer this to paper (plain paper). That is, the third
As shown in the figure, charging and developing devices are arranged around the photoconductor 301 for each color, and after forming a two-color toner image on the photoconductor 301, the transfer charger 307 transfers the two-color toner image onto the paper. is transferred at once, and the toner image is fixed by a fixing device 342, thereby completing two-color printing.

On the other hand, untransferred toner on the photoreceptor 301 is collected by a cleaning group M309, and after cleaning the photoreceptor 301, the next print cycle is started.

In this embodiment, in order to obtain a two-color printed image by rotating the position of the photoreceptor 301, a non-contact developing method is adopted. This is because in a contact development method such as a conventional magnetic brush development method, the first toner image initially formed on the photoreceptor 301 as shown in FIG. 9(A) is , as shown, by the second developer, or as shown in FIG. 9(C), the first developer. The second toners sometimes intermingled and adhered to the photoreceptor 301. Furthermore, as shown in FIG. 10, the first toner that is transported while adhering to the photoreceptor 301 sometimes gets mixed into the second developing device 305, resulting in a significant deterioration of image quality.

Also, as a non-contact development method, there is a method using a magnetic component developer, but since it contains blackish magnetic powder, it is not possible to obtain color toner with high saturation, making it unsuitable for multicolor printing. be.

Therefore, in this embodiment, a two-component developer in which iron powder carrier and non-magnetic toner are mixed using a magnetic brush is used. That is, as shown in FIG. 11, a two-component developer 355 is stirred by a mixer 356 and a magnetic brush roll 357 to be triboelectrically charged. Then, due to the magnetism of the iron powder carrier, the two-component developer 355 is attracted to the magnetic brush roll 357 and conveyed by rotation. The two-component developer 355 forming a magnetic brush is regulated to an appropriate layer thickness by a doctor blade 358, and is rubbed against a non-magnetic developing roll 359. and,
By applying a DC bias voltage 360 between the magnetic brush roll 357 and the developing roll 359, only the non-magnetic toner 355A in the two-component developer 355 is electrostatically separated onto the developing roll 359. This developing roller 359 is connected to the photoreceptor 301 by a gap adjustment ring (not shown).
An appropriate gap (for example, 200 μm) is maintained between the two. Further, since the non-magnetic toner 355A is positively charged due to friction with the iron powder carrier, the developing roller 355A
The nonmagnetic toner 355A conveyed by the toner 59 flies onto the electrostatic latent image pattern whose potential is attenuated on the photoreceptor 301, and development is performed. In addition, developing roll 3
The two-component developer 355 that has been rubbed by the scraper 59 is scraped off by the scraper 361 and used for another development. Further, the toner concentration of the two-component developer 355 is detected by a toner concentration sensor (not shown), and based on this detection, toner is replenished from a toner hopper (not shown) to maintain a constant toner concentration. There is.

Next, Figure 12 (A) shows how to prevent color mixing during multicolor printing.
-(D) and FIGS. 13(A)-(D). FIGS. 12(A) to 12(D) are schematic illustrations showing the occurrence of color mixture. A band M (Fig. 12 (
A> shown in the figure), then the first exposure is performed, and the surface potential of the exposed area is attenuated to Vs, the first toner is attached thereto, and the first development is performed (shown in FIG. 12(B)). After that, when the second exposure is performed, this exposed portion is also attenuated to the surface potential Vs (
(Illustrated in FIG. 12(C)). If the second development is performed in this state, the second toner will develop the first exposed area as well as the second exposed area, resulting in a mixed color (as shown in FIG. 12(D)).
. This development occurs because the potential of the first exposed portion is lower than the development start potential during the second development.

In order to solve this color mixing problem, it is necessary to restore the surface potential of the first exposed portion to the surface potential before exposure. At this time, it is necessary to prevent the surface potential of the unexposed area from changing. In order to satisfy these contradictory factors, a corotron corona discharge charger that superimposes alternating current and direct current voltages is used as the second charger 304 in this embodiment.

Figure 13 shows the color mixing prevention process using this charger (
This will be explained with reference to A) to (D).

(1) The photoreceptor 301 is uniformly positively charged with the first charger 302 (see FIG. 13(A)).

(2) A first exposure is performed with the laser beam a from the first laser diode 314, and a first toner is attached to the exposed portion of the surface potential 1, and a first development is performed (see FIG. 13 (8).
)reference).

(3) Recharging is performed with the second charger 304, and the surface potential of the first exposed area is set to a potential v8 that is approximately equal to the surface potential of the unexposed area.
2 (see Figure 13(C)).

(4) Second exposure is performed with the laser beam b from the second laser diode 315, second toner is attached to this second exposed area, and second development is performed (see FIG. 13(D)).
. At this time, since the surface potential of the first exposed portion is higher than the development start voltage during the second development, the above-mentioned color mixture does not occur.

Next, details of laser scanning in the laser scanning unit 310 will be explained. FIG. 14 is a schematic perspective view illustrating laser scanning of the photoreceptor 301 from the laser scanner unit 310. It should be noted that each member shown in the same figure is given the same reference numeral as in FIG. 3 or FIG. 7, and detailed explanation thereof will be omitted. In this laser scanning, there are two problems that greatly affect image quality. That is, the laser beam a from the first laser diode 314
The scanning start point in the main scanning direction on the photoreceptor 301 is
, the scanning end point is El, and the second laser diode 31
The starting point of scanning by laser beam b from 4 is 82. If the scanning end point is E2, there are problems shown in FIGS. 15(A) and 15(B). FIG. 15(A) shows both scanning starting points St,
82 are not on the same line and produce a difference d. This is the first. Second laser diode 314,3
Laser beams a and b from 15 are connected to the polygon mirror 319
This occurs when the beams are not parallel before entering the plane.

On the other hand, FIG. 15(B) shows the first. Second laser beam 31
The scanning length in the main scanning direction of laser beams a and b by No. 4,315 is J! 1, indicating that it is different from J12. This occurs when there is a difference in the exposure area between the laser beams a and b that have passed through the f/theta lens 320 and exposed the photoreceptor 301.

This embodiment is configured as follows in order to solve the above two problems.

First, the input/output relationship between the LBP unit 300 and the LBP interface 410 is shown in FIG.
This will be explained with reference to FIG. Signals between the LBP unit 300 and the LBP interface 410 are broadly classified into control signals and image-related signals.

As a control signal, the LBP interface 410
There is a command signal such as a print command to the mustard BP unit 300, and a status signal such as a print ready signal that indicates the status of this LBP unit is sent from the LBP unit 300 to the LBP interface 410.

As shown in FIG. 17, the image STM related signals from the LBP unit 300 to the LBP interface 410 include a video clock signal for the main scanning direction and a horizontal synchronization signal for the A1 scanning direction. The first . a second video clock signal;
1st. This is the second horizontal synchronization signal. Also, LBP
The interface 410 is the first. a second video clock signal; a first video clock signal; Based on the second horizontal synchronization signal, the first . A second video data signal is output.

The control system block of the LAP unit 300 is as follows:
Said 1st. a second video clock signal and a first video clock signal; A second horizontal synchronizing signal is generated, and the first horizontal synchronizing signal is generated. It has a print control section 370 (details will be described later) that drives the first and second laser diodes 314 and 315 based on the second video data signal. This print control section 370 is connected to an I10 port 372 of a microcomputer 371. The microcomputer 371 includes the I10 boat 372, which is connected to input/output devices such as various sensors and motors required for printing operations, in addition to the print control section 370, and a ROM 374 that stores an operation program for the LBP unit 300. and RAM375 that stores data.
, a timer 376 that generates a clock, and a scanner CPt 1373 that controls each of these parts.

Next, an example of the printing IIJt11 section 370 will be explained with reference to the block diagram shown in FIG. 18 and the timing chart shown in FIG. 19. FIG. 18 shows that one photodetection element 200 detects the scanning start point of the laser beams a and b, and the scanning start point of the two laser beams a and b to the photoconductor 301, which is one of the problems mentioned above, is detected. Rank 1! This circuit corrects the positional deviation of Et and E2.

In FIG. 18, the photodetecting element 200 detects a laser beam a.
The output horizontal synchronization detection signal S1 is connected to the set terminal of the flip 70 knob 201. Q of this flip 70 tube 201
The output is the line start signal S2 from the quaternary counter 20.
Input to reset terminal R of No.2. Further, the oscillation output 83 (1/4 clock corresponding to 1/4 dot) of the oscillator (O20) 203 is input to the clock terminal of the quaternary counter 202. The clock signal S4, which is the Q output of the quaternary counter 202, is used as a video clock, and the horizontal synchronization detection signal S4 is used as a video clock.
1, and is output with an accuracy of one clock (corresponding to one dot) obtained by dividing the frequency of the oscillation output S3 by four.

On the other hand, the line start signal S2, which is the Q output of the flip 70 tube 201, is sent to the counters 204, 205A, 20
Input to reset terminal R of 6A, and also input to quaternary counter 2.
The clock signal S4, which is the output of 02, is sent to the counter 205B.
, 206B. The counter 204 is a monostable timer, and the counters 205A and 206A are presettable programmable counters. Then, the counter 2
The output S5 of 04 is a sample timer signal that is periodically generated in response to the horizontal synchronization detection signal S1 for the purpose of detecting the horizontal synchronization position and generating sample pulses for the laser light amount stabilizing circuit. In addition, the counter 20
5A indicates the left 7-gin in the horizontal direction, and the counter 20
6A is a counter for setting a horizontal write margin.

In addition, the output S6 of the counter 205A is output to the inverter 207.
A is input to one input terminal of the AND gate 208A, and the output S7 of the counter 206A is input to the other terminal of the AND gate 208A. Then, an AND gate 2 in which the output of this AND gate 208A and the output S4 of the quaternary counter 202 are operated by two people.
The output SIB of 09A is output to the LBP interface 410 as the first video clock signal.

Further, an AND gate 2) OA is provided which handles the output of the AND gate 208A and the first video data signal by two people. This AND gate 2) 0A output and
The output of the OR gate 2) 2A which combines the output S5 of the counter 204 with the signal passed through the inverter 2) 1 is provided as the loser drive signal S9.

This first loser drive signal S9 is transmitted to the first laser diode 3 via the first loser drive circuit 2) 3A.
14 to emit light.

On the other hand, the drive control system for performing the second pack centering is the counters 205A, 206A and the inverter 207A shown in FIG.
, AND gates 208A, 209A, 2) 0A, OR gate 2) 2A, and the loser drive circuit 2) 3A have the same configuration in which the suffix rAJ is changed to the suffix rBJ. The counters 205B and 206B are each programmable, and the output S of the counter 205B is
The left margin in the horizontal direction is set by +o, and the right margin in the horizontal direction is set by the output So of the counter 206B. Also, a second video clock signal @S12 and a second video drive signal S4
3 is the counter 204.3 in the same way as in the case of the first package medium character.
Signals Ss of counter 205B and counter 206B,
, S+o, and S+t.

Note that the counters 205A, 206A, inverter 207A, and AND gates 208A, 209A for outputting the first video clock signal S8 are referred to as a first video clock generation circuit 420. Also, the second video clock signal S
The counters 205B, 206 for outputting 12
B, inverter 207B, AND gate 208B, 20
9B is a second video clock generation circuit 42).

In this way, in this embodiment, two types of laser beams a
, b can be achieved with one photodetector element 200. Conventionally, there are two types of laser beams a,
Since the horizontal synchronization detection of b is performed using two independent photodetecting elements, the number of parts increases and position adjustment of the two photodetecting elements takes time and is complicated. Therefore, according to this embodiment, the cost of the device can be reduced by reducing the number of parts, and the ease of assembly can be improved without requiring complicated adjustment work.

In addition, as shown in FIG. 10(A), laser beams a and b
If a deviation d occurs at the scanning start point St, 82,
Said 1st. Second video clock generation circuit 420, 42)
This can also be easily corrected. That is, the first
By varying the preset value of either the counter 205A that sets the horizontal left margin of the color laser beam a or the counter 205B that sets the left margin of the second color laser beam b, the first color laser beam a This deviation d can be eliminated by delaying the scanning start point E1 of the second color laser beam b or by advancing the scanning start point E2 of the second color laser beam b. Therefore, the polygon mirror 31
This deviation d can be easily corrected without requiring complicated optical adjustment to make the laser beams a and b accurately parallel beams before entering the laser beam 9.

Next, the first section regarding the sub-scanning direction. The configuration for outputting the second horizontal synchronization signals Sn and S20 will be briefly described with reference to the block diagram shown in FIG. 18 and the timing chart shown in FIG. 20. A counter 2) 5A is configured to output the first horizontal synchronization signal ST7.

2) 6A, inverter 2) 7A, AND gate 2) 8A
, 2) 9A are provided. Similarly, counters 2) 5B, 2) are configured to output the second horizontal synchronization signal S20.
6B, inverter 2) 7B, AND gate 2) 8B, 2
)9B is provided.

Here, to explain the output of the first horizontal synchronization signal SL7, the counters 2) 5A and 2) 6A are programmable counters that can be preset.
A is used to set the top margin, and counter 2) 6A is used to set the bottom margin. The page top signal S+4 is input to the gate terminal G of the counters 2) 5A and 2) 6A, and the line start signal S2, which is the output of the Philips block 201, is input to the clock terminal Cp. The subsequent operation can produce the first horizontal synchronization signal Srz in the same manner as the production of the first video clock signal Ss+. The same applies to the creation of the second horizontal synchronization signal S+o.

Next, another configuration example of the printing control circuit 370 that can also correct the mismatch in scanning length shown in FIG. 10(B) will be described with reference to FIGS. 2) to 23. FIG. 2) is a block diagram showing another example of the configuration of the printing control circuit 370, and the difference between the block shown in the same figure and the block shown in FIG. 18 is that a quaternary counter 220 and a selector 230 are added. That's true. Then, the quaternary counter 202
The first clock signal S4 is generated with an accuracy of one clock, whereas the newly added quaternary counter 22
0 generates a second clock signal 84' that is synchronously stretched by 1/4 clock, and thus the lock signal reduces the total number of video clocks and apparently stretches the beam with a short scan length. I have to. The selector 100 is the first. Second clock signal Sa
, 84' are input, and the second clock signal S4' is selected and output for a beam with a short scanning length.

In this embodiment, the scanning length correction means 242 that corrects the scanning length of the beam in this manner corrects the scanning length of the beam in accordance with the scanning length of the beam. Second steering signal Ss, Sa'
a reference clock generation circuit 234 that outputs the reference clock as a reference clock; It is composed of a selector 230 that selects and outputs to the second video clock generation circuits 240 and 241.

Here, the details of the quaternary counter 202, 222 and selector 230 in the scanning length correction means 242 will be explained in the second section.
This will be explained with reference to FIGS. 2 and 23. In FIG. 22, reference numeral 22) is a presettable N-ary counter, which counts the oscillation output S3 of the oscillator 203 after the horizontal synchronization detection signal S1 is output from the photodetector element 220. The preset value of 22) can be arbitrarily set using, for example, a dip switch 222 shown in the figure. Shift register 223, Nantes gate 224. Noah gate 225 and inverter 22
6 is a gate circuit that provides a predetermined operation to the N-ary counter 22). Clock terminal C of shift register 223
The oscillation output S3 is input to P, and the line start signal S2 is input to the reset terminal R.The Qo and Q1 outputs are input to the Nant gate 224, and the Q2 output is input to the N-ary counter. 22) CI.

Input to GE terminal. Further, the output of the NOR gate 224 and the output of the inverter 226 are inputted to a Nandt gate 225, and the output of this Nandt gate 225 is inputted to the LD terminal of the N-ary counter 22). still,
The inverter 226 receives a carry from the co terminal of the N-ary counter 22). Here, as shown in FIG. 23, after the line start signal S2 is input to the reset terminal R of the register 223 and the N-ary counter 22), the oscillation output S3 is input to the register 223. N-ary counter 22)
When input to the gate terminal Cp, the output 82) of the NOR gate 225 is output. The Q2 output SZZ of the register 22) is input to this N-ary counter 22) as a signal shown in the figure, and the carry output S23 is input to the CO terminal of this N-ary counter 22).
will occur. And this carry output Sz
a is a JK type rough flip-flop or less JK-F which is inverted via the inverter 226 and constitutes a quaternary counter.
- Abbreviated as F > 227, 228 one of JK/F-F
It is designed to input to the terminal J of 227. still,
The J terminal of the other JK-F-F228 is always at a high level. Here, this JK-F-F227.2
28 performs a toggle operation at the rising edge of a clock input when both terminals J and J are at a high level, and maintains the previous state when both terminals J and J are at a low level. And the reset terminal R of this JK-F-F227.228
Since the line start signal S2 is input to the JK-F-F 227 and 228, the JK-F-Fs 227 and 228 start operating in synchronization with the input of the line start signal S2.
-The oscillation output S3 which is the clock input of F-F227
will be divided into four. And the JK-F-F2
When a carry occurs in the N-ary counter 22), in which both terminals J and 27 are at low level, the oscillation output S
The toggle operation is interrupted for one clock of 3 (corresponding to 1/4 dot). As a result, the latter JK-F-
As shown in Figure 23, when the pulse interval during normal operation is set to "1", the output of F228 is r when a carry occurs.
It becomes 11/4 J, and the draw is extended by 1/4 clock.

On the other hand, the counter 202 has two JK-F-F202
A, 202B, its J.

Since the K terminal is always at a high level, its Q output becomes a clock whose frequency is accurately divided by four as shown in FIG.

A selector 230 inputting the outputs of both quaternary counters 202 and 220 is connected to AND gates 231 and 234 inputting the outputs of the quaternary counter 220 and the quaternary counter 202.
It has AND gates 232 and 233 which input two outputs. The other input of the AND gates 231 and 233 receives a high level when the switch 235 is set to "interval", and receives a low level when the switch 235 is set to rlmJ. On the other hand, the other input of the AND gates 232 and 234 receives a low level due to the action of the inverter 236 when the switch 235 is opened, and receives a high level when the switch 235 is set to l[J. It has become. Also provided are an OR gate 237 that allows two people to output the AND gates 231 and 232, and an OR gate 238 that allows two people to generate the outputs of the AND gates 233 and 234.

Therefore, when the switch 235 is opened,
The OR gate 237 outputs the second clock signal @84' which is the output of the quaternary counter 220, and the OR gate 237
8 outputs the first clock signal S4 which is the output of the quaternary counter 202. In addition, the switch 23
Conversely, when 5 is set to "rll", the first clock signal S4 is output from the OR gate 237, and the OR gate 23
8 outputs the second clock signal Sa'. If the second clock signal S4' is used as a video clock for one beam with a short scanning length by switching the switch 235, the scanning length on the photoreceptor 301 can be increased.

For example, a description will be given of correction when one of the laser beams whose normal scanning length is 200 am is one layer shorter. When the resolution is 12 lines/jIII, the video clock signal of the beam with a short scanning length is
00 pulses (200xl 2) need only be stretched by 12 pulses. Here, since the oscillation output S3 which is the clock input of the N-ary counter 22) is a 1/4 video clock, the preset value of the N-ary counter 22) is set to a value such that 1 carry occurs every 50 counts. Just set it. In this way, the difference in scanning length as shown in FIG. 10(B) can be corrected. In addition, N-ary counter 22)
The preset value is the beam scanning length.

The scanning length difference can be corrected by setting it appropriately according to the scanning length difference between the two beams and the resolution.

Next, various picture (1111 collection functions) in this device will be explained.

First, the above 1. An example of the second operation panel 6.101 will be described with reference to FIG. 24.

the first operation panel 6 for inputting image editing information;
is equipped with various keys as shown in FIG. The composition mode selection key 50 is a key for selecting a mode in which images of a plurality of documents sequentially supplied from the ADF 1 are composited onto one sheet of paper and output. In addition, when ADFl is not used, a mode is selected in which the images of originals placed one after another on the exposure glass 111 are combined onto one sheet of paper and output. Further, a first numeric keypad 56 is provided as a document number input means for inputting the number of document sheets whose images are to be combined on one sheet. Incidentally, the reference numeral 57 in the figure is a sheet number display that displays the number of original sheets inputted using the first ten-key pad 56. The image extraction mode selection key 51 is a key selected when extracting not an image of the entire document but a part of the image and copying it onto paper. As a means for specifying the extraction area of the document, for example, the coordinates of the extraction area are inputted via the first numeric keypad 56 using the coordinates 5A marked around the LCD 5. By the way, when the above-mentioned compositing mode is selected by the above means, it is possible to specify the extraction area for a plurality of documents, and also to specify division of the extraction area for one document. The output position designation mode selection key 52 is a key for selecting a mode for designating a position at which a document image is formed on sheets fed from the upper cassette 32) or the lower cassette 322, etc. The coordinates 5A and the first numeric keypad 56 serve as paper image forming device designation means.
It is designed to be used for both purposes.

The image erasure mode selection key 53 is a key that is selected when partially erasing an image on a document. Particularly, when the combination mode is selected, this is effective for erasing the outlines of a plurality of documents. Note that the means for specifying the image erasure area is the coordinates 5A and 5A.

1 numeric keypad 56 is also used. The framed mode selection key 55 is a key that is selected when adding a new outline after the outline of the document has been erased by selecting the image erasing mode. The pagination mode selection key 55 is a key selected when adding pages to a sheet of paper. In this embodiment, there are two types of page attachment modes; one is a mode in which pages are attached in the order in which the originals are input, corresponding to the images of a plurality of originals formed on one sheet of paper during the composition mode. The other mode is a mode in which pages are attached in the order in which paper is output. When selecting the former mode, press the "input order" selection key 55 after pressing the mode selection key 55.
Press A. When selecting the latter mode, after pressing the pagination mode selection key 55, the "output order" selection key 55B is pressed.

Next, the second operation panel 101 for inputting print information and the like will be explained. In FIG. 24, 150 is a start key for starting a copying operation, and 151 is a second numeric keypad, which is an example of sheet number input means for inputting the number of sheets on which the same original image is to be copied. This second
The number of sheets entered using the numeric keypad 151 is displayed on the sheet number display 1.
52, and a cancel key 153 for canceling the number of sheets is provided. 154 is a cassette selection key for selecting the upper cassette 32), and 155 is a cassette selection key for selecting the lower cassette. 15
Reference numeral 6 denotes an LCD display that displays various states of the printer, and indicates a standby state of the printer.

It is designed to schematically display information such as paper size information, occurrence of jams, toner replenishment, etc.

Further, 157 is an auto magnification mode selection key, and when this key is pressed, the original image is automatically enlarged or reduced based on the size of the original image and paper. Reference numeral 158 is a magnification specifying key, and by selecting a numerical value with the second numeric keypad 151 after pressing this key, a desired enlargement or reduction magnification can be set. Reference numeral 159 is a key for selecting a reduction or enlargement mode in accordance with a predetermined original size or paper size.

Next, a page memory address controller that performs various image editing operations based on input information to the first operation panel 6 will be described. In this embodiment, the first color is used to form two-color images.

2nd color page memory address controller 404°40
6, both of which have the same configuration. FIG. 25 is a block diagram showing an example of the first color image memory address controller 404.

This page memory address controller controls the address and read/write signals of the page memory.

First, page memory address control will be explained.

The page memory address controller shown in this example is as follows:
This is provided to efficiently use page memory. The address of the page memory is usually determined by applying a read/write signal as a count in the main scanning direction and a horizontal synchronization signal (H8YNC) signal as a count in the sub-scanning direction. by the way,
When specifying page memory addresses through such control, a good number for dividing the page memory in the main and n1 scanning directions is 1024, 2048.4096.8192.・
...and is a multiple of 2. However, the number of main scanning directions actually used is rarely close to the above number, and in the case of this device, the main scanning width is approximately 5000 pits (approximately 625 bytes), and the sub-scanning width is approximately 7000 pits (approximately 625 bytes). (approximately 875 bytes).

Therefore, to satisfy this address space, 8192X
An address space of 8192 bits (1024 bytes x 1024 bytes) is required, and both the memory element and the counter element are wasted.

In order to minimize the above-mentioned waste, the device of this embodiment has XW
(TP) register 423. Adder/subtractor 424° latch circuit 425. An address control block consisting of an address counter 426 and an address transceiver 427 is provided. Here, Xw is a value corresponding to the width of the output paper (width in the main scanning direction), and based on the outputs of the upper and lower cassette size detection switches 325 and 328, the
01 determines this XW and transmits the XW via the CPU bus, data transceiver 420 and command boat 42).
(TP) Set in register 423. Also, set the read/write start address (TP) in the same way as XW (
TP) register 423, the above address control block inputs the H8YNC signal to
The number P+XWXN (N is an integer) is accessed, and the start address in the main scanning direction is accessed. Also, when a read signal (PRDC) or a write signal (PWTC) is input from the image bus to the line control I/clock generator 437 via the Otsu receiver 440, a write/read clock synchronized with the read signal and write signal is generated. This clock is used to sequentially update the addresses in the main scanning direction. By specifying addresses in this manner, the addresses become continuous one-dimensional numbers with almost no spaces, and the number of memory elements and counter elements can be kept to a minimum. Note that when the composite mode of forming multiple original images on one sheet of paper is selected, the start address (
It is sufficient to set the

Next, a description will be given of a block that controls partially reading data from the page memory or partially rewriting data. For this purpose, the XN register 430. XN counter 431. YN register 432 and YN counter 43
3 is provided.

XN and YN are values in the main scanning direction and sub-scanning direction that specify areas on the image memory, respectively, and these values are
01 via the command port 42)
N register 430. It is set in the YN register 432. The values of XN and YN are set in the XN and YN counters 431 and 433 that count the read/write clock, and when the XN counter 431 counts the read/write clock by XN, it outputs a carry and performs a carry in the sub-scanning direction. And XN, YN counter 431,
When a carry is output from 433, it means that the access range specification has been completed. At this time, line system t
Based on the output of the lIl/clock generator 437, the status transceiver 439 generates a page end signal (PGE
ND) is output to the image bus, and all data in the access range is cleared.

Note that in this embodiment, it is possible not only to erase specific data in the page memory, but also to write specific data. At this time, after setting TP, XN, and YN to specify the data writing position in the same manner as above,
DMA (Direct Memory Access) shown in the figure
This data is written onto the page memory by programming the data address and data length at which data to be written is stored in the controller 411 and enabling the DMA operation. Note that the data to be written is stored in the program memory 402.

In this case, the data may be a character, a symbol, or a specific pattern, such as a page code or an outline of a document.

Mask register 434. The mask counter 435 is used to invalidate a certain range of image data in the page memory, and when an address corresponding to a predetermined range is set in the mask register 434, the data in that range is forced to zero. It has become so.

Address register 436 allows CPU 401 to recognize the address currently being accessed by this page memory address controller. This address is provided for data transceiver 420 . C.P.
The data is transferred to the CPU 401 via the U bus.

Note that the line control receiver 438 receives a line synchronization signal (NX
The bus control receiver 441 receives a data high enable signal (DHENB) and an image disable signal (IMDIS) and transfers them to the line control/clock generator 437.

Next, the page memory as an image memory will be explained. The first color and second color page memories 403 and 405 have a configuration as shown in FIG. This page memory 403 can store 1 or 2 Mbytes of data according to the address signal output from the page memory controller 404. As a memory element, 64 256-bit dynamic RAMs are used, and the memory space is 2M bytes. The bus commonly used is the image bus, which is the page memory address controller 404, 406 . Image data controlled by each control signal from the print control section 370 and the like is read/written from this image bus via a data buffer 403A. In addition, the above-mentioned D
Data buffer 4 is sent from the CPU bus only in MA mode (a mode used when writing page codes or the outline of a document, etc.).
Data is written through 03B.

Next, the configuration of the scanner interface 409 will be explained with reference to FIGS. 28 to 30.

This scanner interface 409 is connected to the CPU 401
The control signal from the CPU 4 is transmitted to the scanner unit 110, and the status of the scanner unit 110 is transmitted to the CPU 4.
01 side, and also has the role of reducing or enlarging the read image data and transmitting it to the page memories 403 and 405. That is, as shown in FIG. 28, an address signal is input from the CPU bus to the address code converter 450, data is input to the bus transceiver 458, and various data are input to the basic command register 452 according to the address.
．． The status data of the scanner unit 110 written to either the command register 453 or the status bus receiver 454 or the basic status receiver 455 is transferred to the path transceiver 45.
8. The data is read into the CPU 401 via the CPIJ bus. In this way, the scanner unit 11
0 and reads the status of the scanner unit 110 to the CPU 401. Also,
Among the interface signals between this scanner interface 409 and the scanner unit 110, data (IDAT) is input/output via the path transceiver 457.
has a bus structure, and a status signal (I
It has three states depending on the states of two signals: sDAT) and command signal (ICMD). That is, the status data of the scanner unit 110, the scanner unit 110
It has three states: command data to the scanner unit 110 and image data read by the scanner unit 110. Furthermore, the timing for transmitting and receiving various data is determined by the hygienic signal (ISBSY) outputted from the scanner unit 110 and the write signal outputted from the timing generation section 451! (IWR) etc. Furthermore, interrupt F/
F459 outputs an interrupt signal (INTO) to the CPU 401.

The image data from the scanner unit 110 input via the path transceiver 457 is processed by the image processing section 45.
6 and enlarge the image here.

The image is subjected to reduction (processing related to the main scanning direction) and trimming (image extraction), and then sent to the image bus.

Details of this image processing section 456 will be explained with reference to FIG. 29. This image processing section 456 has two line memories 46
0.461, and these two line memories 460.4
The image is enlarged or reduced by alternately reading and writing to and from 61. Note that since it is necessary to read and write image data as serial data into this line memory 460 and 461, the image data that is input in parallel is converted into serial data by a parallel-serial converter (hereinafter referred to as a P-S converter) 462. The image data read out from the line memories 460 and 461 is subjected to serial-to-parallel conversion (hereinafter referred to as □S-P converter) 463 and outputted in parallel to the converter image bus.

Various blocks output an address signal for reading and writing to the line memory 460, 461, a write/read timing signal, and a timing signal for setting the conversion timing of the P-8 converter 462.8-P converter 463. It is provided. Write timing generation circuit 4
64. The read timing generation circuit 465 outputs two types of clocks: 8 clocks corresponding to 8-bit image data and a clock signal delayed from the 8 clocks each time a strobe (STB) signal is input. This clock is then transmitted to the P-8 converter 462. used as the timing signal of the S-P converter 463 and as the write/read timing signal via the timing selector 467,
Furthermore, it is used for generating address signals.

As a block that generates the address signal, there is a line memory address counter parameter register 468. Decimal counter section 469. Decimal address counter integer part 47
0. An integer address counter 471 and two address selectors 472, 473 are provided. The line memory address counter parameter register 468 is
An enlargement or reduction magnification to be counted is set for the decimal counter section 469, and initial values are set for the decimal address counter integer section 470 and the integer address counter 471. Decimal counter section 469
adds the enlargement and reduction magnifications for each clock and outputs the carry of the sum of the decimal parts. For example, in the case of 0.7 times, a carry is output up to the third clock, but no carry is output at the fourth clock. (0,7X3
-2.1,0.7X4=2.8, so there is no decimal carry). The decimal address counter integer section 470 is configured to advance the count only when a carry occurs in the decimal address counter section 469.

On the other hand, the integer address counter 471 is configured to advance the count every clock.

When data is reduced, the output of the decimal address counter integer part 470 is used as an address to store the line memory 472.
Alternatively, by writing data to 473, every few pieces of data are dropped and written into 1, and the read address is determined by the integer address counter 471 to generate reduced data. On the other hand, when expanding data, the integer address counter 471 writes the data as it is to the line memory 471 or 473, and the read address is determined by the decimal address counter integer part 470, so that the same data is read out one by one in succession. Enlarged data is now created. For this purpose, the decimal address counter integer part 470. Address selector 4 inputs the outputs of the integer address counters 471 and selects and outputs them to the line memories 460° 461
72.473 is provided. Note that the selection of addresses with this address selector 472 and 473 is expanded.

This is done based on the output of the reduction timing controller 474.

Here, the data reduction and expansion operations are shown in Fig. 30 (A).
This will be explained with reference to the timing chart shown in 8). FIG. 30(A) is a timing chart showing the data writing operation to the line memories 460 and 461.
Figure (B) is a timing chart showing the data read operation from the line memories 460 and 461. data 0
08 to D01 are made into serial data by the clock CP from the write timing generation section 464. Further, the decimal counter section 469 outputs a carry from the rising edge of the clock CP, and has a reduction magnification such that no carry is output at the seventh clock, for example.

Therefore, the decimal address counter integer section 470 sequentially updates the write address only while a carry is output from the decimal counter section 469, but does not update the write address when a carry is not output, and data 002 , the common address ADS for DOl
+6 will be specified. As a result, the same address data D02 and DOI are continuously written on the line memory, and as a result, the data DO2 is erased, resulting in data loss. Since this data is read out using the address of the integer address counter 471 that is updated in response to the clock CP as shown in FIG. will be generated.

When expanding data, the integer address counter 47 is updated in response to the clock CP as shown in FIG. 30(A).
Data entry is performed in the line memory 460 or 461 depending on the address of 1. Therefore, data 008 to 001 are written to the line memory as they are. Then, data is read from this line memory based on the address of the decimal address counter integer section 470.

For example, as shown in FIG. 30(B), the decimal count section 4
If 69 is the sixth clock CP and the magnification is such that no carry is output, the decimal address counter integer part 470 rotates the same address (ADS+5) twice without updating the address while this carry is not output. They are specified consecutively, and as a result, the same data is read out continuously and the data is enlarged.

In addition, the above enlargement and reduction operations will enlarge the image in the main operation direction.
This is a case of reduction, and the enlargement or reduction of the image in the sub-operation direction is performed by changing the scanning speed of the image cartridges 116° and 117, as described above. Also, when in the same-size mode, the same-size mode signal is input to the decimal count section 469, and the decimal address counter integer section 470 outputs the same address as the integer address counter 471, resulting in enlargement.

No reduction is performed.

Next, image extraction (
trimming). This trimming is performed by extracting data in the image extraction area by defining a data start position and a data end position. To set the starting position of data, connect the most significant bit of each layer write address and read address to the chip select terminal of the memory element, and set it so that writing and reading are possible after that bit becomes 1. and do it. The end position of the data is set at the address. Next, image extraction (trimming) is performed in this image data processing section 456.
I will explain about it. This trimming is performed by extracting data in the image extraction area by defining a data start position and a data end position. To set the starting position of data, connect the most significant bit of each write and read address to the chip select terminal of the memory element, and then read it after that bit becomes 1.
Set it so that it can be read. The end position of the data is set by setting an address in the address comparator 475, and by this address comparator 475, the gate 4 provided after the P-8 converter 462 is set.
76 or by controlling the data selector 478 provided before the S-P converter 463. Note that this address comparator 475 is connected to the integer address counter 47.
The operation is performed by inputting address 1.

Therefore, when the image reduction mode and cropping are performed together, the integer address counter 471 is used when reading data, so the data selector 478 that selects the read data is controlled by the address comparator 475. will be done. On the other hand, when image enlargement mode and cropping are performed together, the integer address counter 47 is
1 is used, the gate 476 that preselects the data to be written will be controlled by the address comparator 475.

The above trimming operation is performed in the main scanning direction, and trimming in the sub-scanning direction is performed as follows. That is, sub-scanning direction parameter register 480, address counter 481 . Address comparator 482 and gate 483
is provided.

This configuration corresponds to the trimming block in the main scanning direction described above. The most significant bit of the address counter 481 is connected to the gate 483 for the horizontal synchronization signal (MH8YN) and slope signal (MSTB), and if this bit does not become 1, both signals are output to the image memory. It is designed so that it will not happen. This restricts the starting position of data in different scanning directions.

The end position of the data in the sub-scanning direction is determined by setting a value corresponding to the end position of the data in the address comparator 482. and address counter 482
When an address equal to or greater than the above value is counted by the address comparator 482, the data selector 478
control to force the data to zero. As a result, zero data is written into the page memory, and truncation in the sub-scanning direction is performed.

Next, regarding the LBP interface 410, a third
This will be explained with reference to FIG. This LBP interface 410 converts the control signal from the CPU 401 into LB.
In addition to informing the P300, the status of the LBP300 is also sent to the CPU.
410 and plays the role of transmitting the image data in the page memories 401 and 405 to the LBP 300. That is, the address signal is sent from the CPU bus to the address receiver 48.
5. Input via the address decoder 486 and read data on the CPU bus or LBP3 according to this address signal.
00 data is loaded into each register, and the CPU 401 reads the contents of each register, resulting in LBP30.
It sends commands to 0 and reads the status of LBP300. The registers include printer command register 490, printer status register 491. A command register 492 and a status register 493 are provided. Data on the CPLI bus is also input via a data transceiver 487, and a print request signal (PREQ) from the LBP 300.

Printready messages @ (PRDY) etc. are sent to receiver 489.
The print signal (PRT) and the like are output to the LBP 300 via the driver 495. In addition, this LBP interface 410 and L
Data DAT8 to DAT1 exchanged with the BP300 via the transceiver 488 have a bus structure, and two signals, a status signal (DSTA) and a command signal (DCOM), are output from a timing control circuit 499, which will be described later. It has three states depending on the state.

That is, the status signal of LBP300.

It has three states: a command signal to the LBP 30o and an image signal to the LBP 300. The timing control circuit 499, which determines one of these three states, receives read/write signals from the bus interface 494, command information from the command register 492, synchronization signals from the transceiver 498 and the receiver 489, etc. Various signals are output to the LBP 300 based on. Further, the image signal from the image bus is sent to the data receiver 496. The data is transmitted to the LBP 300 via the data latch circuit 497 and the bus transceiver 488.

Next, various image editing operations performed by the apparatus of this embodiment will be explained.

Image Composition Mode> First, an image composition mode in which a plurality of original images are composited and formed on one sheet of paper will be described with reference to FIG. 32. This mode is selected by pressing the composition mode selection key 50 on the first operation panel 6. When this key 50 is pressed, a plurality of documents are successively read by the scana unit 110 and sent to the photoelectric conversion unit 120.
is converted into a digital signal. When using ADFI, multiple originals are automatically fed one by one and read one by one. When not using ADFI, the original cover 2 is opened and closed for each original and the exposure glass 111 is read. A document is manually placed on top of the scanner, and each document is read one by one.

For example, the manuscripts P1, P2, P3, shown in FIG.
The images of P4 are read one by one in the above manner.

The image read in this way is transferred onto the image bus via the scanner interface 409, and in the case of monochrome copying, it is stored in the image memory under address control of the first color page memory address controller 404, which is a write control means. It is written to the first color page memory 403.

At this time, the first color page memory address controller 40
4 sets the top addresses TP1 to TP4 on the image memory 403 as shown in FIG. 32 according to each original image, and writes each image to a different address on the image memory 403. Then, the contents of this image memory 403 are LBP
LBP unit 300 via interface 410
The first laser diode 314 is driven to emit light to form an electrostatic latent image of a composite image on the photoreceptor 301. Thereafter, based on the operation of the LAP unit 300 described above, four original images are formed on one sheet of paper T, as shown in FIG. Such a compositing mode allows a plurality of original images to be formed on one sheet of paper in a single image forming operation, reducing copying processing time and reducing paper consumption. still,
For those without ADFI, images can be combined by placing multiple originals on the exposure glass 111 at once, but if it is not possible to place two or more originals at once, use A3 size, for example. This compositing mode is convenient when compositing multiple originals. Also, A
When you select this composition mode using DFl, A
The compositing operation is performed for each document of a plurality of valves that are sequentially and continuously fed from the DFl, and the above operation can be performed continuously until the document presence detection switch 16 detects that there is no document, thereby reducing the burden on the operator. significantly reduced.

Further, when such a composition mode is selected, it is convenient to reduce the size of each of the plurality of original images and form them on a single sheet of paper. Therefore, auto magnification mode selection key 1
By using the 579 magnification designation key 158 or the magnification selection key 159, the original image can be reduced and written in the image memory 4O3, and a composite image can be formed on a sheet of a predetermined size. Regarding image reduction, as described above, data in the main scanning direction is reduced by the image processing unit 456 of the scanner interface 409, and data in the sub-scanning direction is reduced by the carriage 1.
16. Reduce the size by varying the scan speed of 117.

Image compositing mode (10) Variable number of originals to be combined> Although the image compositing mode described above can be performed by fixing the number of originals to be combined in the apparatus, it is more practical to make the number of originals to be combined variable. In this embodiment, the composition mode selection key 50
After pressing , the first numeric keypad 5 as a means for inputting the number of original sheets
By operating 6, the number of originals to be combined can be set as desired. Then, the plurality of originals specified by the first numeric keypad 56 are sequentially read and formed into one sheet of paper. Note that the first color page memory address controller 404, which is a write control means, sets the top address TP according to the specified number of originals, and stores the plurality of original images in the image memory 4.
This means that writing will be specified to a different address of 03.

<Image compositing mode - number of composite originals, variable number of output sheets> It would be more practical if the image forming operation of composing a predetermined number of originals onto one sheet of paper could be performed continuously on a plurality of output sheets. In the device of this embodiment, the second operation panel 10
1, there is a second numeric keypad 15 which is a means for inputting the number of output sheets.
1 is provided to make the number of sheets of paper to form and output the same composite image variable. Additionally, the laser scanner unit 310
Based on the image data of a plurality of original documents written in the image memory 403, latent images are continuously formed on a specified number of sheets per rotation of the photoreceptor 301, and the upper cassette 3
2) Alternatively, copying operations are performed continuously on sheets fed from the lower cassette 322. Therefore, each document only needs to be read once.

<Image extraction area specification and image formation position specification> For example, the third
Extract the effective image D1 of the original P shown in Figure 3 and print it on the output paper T.
The operation for forming the image D2 by reducing it at a predetermined position with a magnification M will be described. The extracted image D1 of the original P is -
Corner coordinate position Xt, Yt and image size At, Bt
It is specified by Further, the image forming position of the image D2 on the output paper T is specified by the coordinates X2 and Y2 of one corner of the image P2. Therefore, as an example for specifying the coordinates and size, for example, the information shown in FIG. 34 may be displayed on the LCD 5, and the input of numerical values corresponding to each piece of information may be requested using the cursor 5B. That is, when the image extraction mode selection key 51 and the output position specification mode selection key 52 on the first operation panel 6 are selected, the above display is performed on the LCD 5 under the control of the CPU 401. And cursor 5B
By inputting information corresponding to the position via the first numeric keypad 56, the image extraction area and image forming position can be specified. Once the image extraction area is designated as described above, the read image is subjected to the aforementioned reduction operation and trimming operation in the image data processing unit 456 of the scanner interface 409. Further, when an image forming position is specified, the top address TP is set to a predetermined value by the image memory address controller 404, which is a writing υ control means, and the image memory 403 corresponding to the specified image forming position is Write to address.

After that, if an image forming operation is executed based on the contents of this image memory 403, an image wiD2 as shown in FIG.
can be formed on the paper T.

Image composition mode + image formation position specification> In this example,
The above-mentioned designation of the image forming position can also be performed in the image composition mode.

That is, as shown in FIG. 35, the originals P1 are sequentially read.
It is possible to designate the image forming position for each of the images from P4 to rearrange the images and form them on the paper T. On this occasion,
After pressing the composition mode selection key 50, the first numeric keypad 56
Operate to set the number of originals to be combined. After that, when the image forming position designation mode selection key 52 is pressed, the third
The screen shown in FIG. 4 is displayed on the LCD 5. Note that when the image extraction mode selection key 51 is not selected, information regarding rREADJ is not displayed in FIG. 34.

Then, according to this display, the first numeric keypad 56 is operated to set the image forming position coordinates X2, Y for each document P1 to P4.
2 should be specified. Based on this designation, the page memory address controller 404, which is an in-store control means, determines the top address of each document image in the image memory 40 according to the coordinates X2°Y2. As a result,
As shown in Figure 35, the paper T is different from the original input order.
Each image can be combined and formed at the upper position.

<Designation of extraction area division for one sheet of original image> When one sheet of original P has multiple images as shown in Fig. 36, each image is extracted and formed on different sheets of paper T1, T2, and T3. mode. At this time, press the image extraction mode selection key 51 to display rREADJ as shown in FIG. Specify the extraction area of image rAJ within. For example, the user presses the image extraction mode selection key 51 again to sequentially designate the extraction areas of images rBJ and rcJ in the document P in the same manner. When division is specified in this way, the CPU 401 connects the scanner unit 110 to the scanner interface 409.
The drive control is performed via the drive control, and images of the same document P are read continuously for the number of divisions. Then, the page memory address controller 404, which is a one-input control means, trims the image according to the order specified for division for each reading operation, and writes the extracted image in the memory 403. Furthermore, the LBP unit 300 sequentially performs image forming operations on different sheets of paper based on the contents in the image memory 403, thereby producing an extracted image "A" as shown in FIG.

rBJ and rCJ are different papers Tt and T2, respectively.
.

It can be formed on T3. In addition to such division designation, it is also possible to designate an image forming position and/or select a reduction or enlargement mode.

Auto Magnification Mode> Next, a mode for automatically setting the copy magnification of an image based on the operation of the auto magnification mode selection key 157 provided on the second operation panel 101 will be described.

In order to automatically set the copy magnification, it is necessary to detect at least the size of the original image and the size of the output paper in advance. When using ADF1, the vertical and horizontal sizes of the document are detected by the document width detection switch 14 and the document switch 2). Furthermore, when the image extraction mode is selected, the size A1°81 of the image extraction area shown in FIG. 33 can be detected manually. On the other hand, the size of the output paper is the upper and lower cassettes 32). An upper cassette size detection switch 325 or a lower cassette size detection switch 32 detects the paper size by determining the type of cassette 322.
Detected by 8. The CPU 401 can input this size information via the CPU bus and detect the size of the original and output paper in advance. and,
When the auto magnification mode selection key 157 is pressed, the CPU 401 can calculate the copy magnification from the size information. The CPU 401 then scans the scanner unit 110 via the scanner interface 409.
The scanning speed of the carriages 116 and 117 is controlled based on the copying magnification to perform an enlargement or reduction operation in the sub-scanning direction.

Further, information on the copying magnification is sent to the image data processing unit 456 of the scanner interface 409 to perform enlargement and reduction operations in the main scanning direction. In this way, an image forming operation based on the auto magnification mode is performed. Further, such auto magnification mode can also be performed in conjunction with the above-mentioned combination mode. In the composite mode, the copy magnification is automatically set for each document to be composited.

Compositing mode + original contour erasing mode> When forming multiple original images on a single sheet of paper, the outlines of each original may be formed on the paper, resulting in an unattractive copy. . In the device of this embodiment, after pressing the image deletion mode selection key 53, the first numeric keypad 56
By specifying the contour area, the image data of this area can be forced to zero on the image memory 403. For example, as shown in FIG. 37, the outline areas of the document ■, ■
.

When erasing (1) and (2), the CPU 401 sends an
．． XN2. YNl, YN2 and top address TPz~T
Pa is given and sequentially set in each register 423, 430, and 432.

When all data in area (2) is to be cleared, TP1 is written to each of the registers 423, 430, and 432.

XN1. The operation is started by setting YNI respectively and setting the all clear command assigned to a specific bit of the command boat 42) to "1". The page memory address controller 404 first outputs the address of TPl to the image bus via the address transceiver 427, and at the same time sets a signal on the image bus that disables the data bus to "1". Outputs a write signal for. Next, a write signal is output while sequentially updating the address from the address transceiver 427, and when this operation is repeated XN1 times, a carry is output from the XN counter 431. Then, only one YN counter 433 is updated, and the address is set to the value of TP1+XW. The above operation is performed until the YN counter 433 counts YN once, and when this value is counted, the YN counter 433
A carry is then output, and the all-clear operation of the area (2) is completed. Similarly for areas ■～■, TP2～
TPa, XN1. XN2. YNI.

This can be done by setting YN2. Furthermore, in the case of composite mode, the outline area of each document is
, YN, the outline of each document can be erased on the image memory 403.

Outline Writing Mode> After erasing the outlines of the originals to be combined as described above, new outlines of each original can be written on the image memory 403. At this time, the image deletion mode selection key 53. After specifying the contour area to be erased with the first key 56, the mode selection key 54 is pressed to select a frame as the contour writing mode selection means. Then, following the above-described erase operation of the contour area, a new contour line is written in this area, that is, the writing position of the contour line is
01 to each register via the command boat 42).
Set P, XN, YN, and the CPU 401 is the 26th
The data address and data length where the data to be written are stored are programmed into the DMA controller 411 shown in the figure, and the DMA operation is enabled. DM
The A controller 411 automatically accesses the specified address on the image memory 403 and writes "1" to the corresponding address on the contour line to frame it.

The above-mentioned DMA controller 411 is capable of writing various data onto the image memory, and is not limited to only the outline of the document. For example, page numbers may be attached to the output paper. The number as the page code is stored, for example, in a memory below the program memory 402, and the DMA controller 411 can read this page code information from the program memory 402 and write it onto the image memory 403. There are two types of page code writing modes.

One is to press the page mode selection key 55 and the "input order" selection key 55A on the first operation panel 6 to form images of each document in the composite mode as shown in FIG. 38. This is a mode in which a page code is attached to a position corresponding to an area. The other one is the paged mode selection key 55.
By pressing and "output order" selection key 55B,
As shown in FIG. 39, this is a mode in which page numbers are attached to the sheets in the order in which they are output.

In the former "input order" mode, the CPLJ 401 can detect each top address TPt to TPa and the size XN, YN of the page code forming area shown in FIG. 38 from the output paper size and the number of combined original sheets. Each data is stored in each register 423 of the page memory address controller 404.
, 430, 432 via the command board 42), and thereafter each page code can be written on the image memory 403 by the DMA controller 411.

Even in the winner's "output order" mode, the top address TP and size X of the page code formation area are determined from the output paper size.
N, YN can be detected, and these data can be set in each register 423, 430, and 432 via the command boat 42), and page codes can be assigned in the output order by the operation of the DMA controller 411.

Note that the above-mentioned "input order" mode and "output order" mode can be used together, and furthermore, the image forming position designation mode, trimming, enlargement, and reduction mode can also be used together.

Note that the present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the paper of the present invention.

[Effects of the Invention] As described above, according to the present invention, by providing a composition mode selection means, it is possible to combine and form a plurality of original images on one sheet of paper, and also by providing a composition mode selection means. Accordingly, it is possible to provide a digital image forming apparatus in which the number of original sheets on which an image is to be formed on one sheet can be made variable.

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of an apparatus according to an embodiment of the present invention, FIG. 2 is a main control block diagram of the apparatus according to the embodiment, FIG. 3 is a schematic cross-sectional view of the apparatus according to the embodiment, and FIG. 4 (A). (B) is a partially cutaway plan view and a schematic sectional view of the four original loading machines, FIG. 5 is a control block diagram of the scanner unit, and FIG. 6 is a schematic explanation of the main timing signals for document reading by the scanner unit. 7 is a schematic sectional view of a laser scanner unit, FIGS. 8(A) and 8(B) are schematic explanatory views showing an example of the arrangement of the exposure portion of a photoreceptor, and FIG. 9(A). (B) and (C) are schematic explanatory diagrams explaining the drawbacks when two-color printing is performed using the contact development method, and FIG. 10 is a schematic diagram explaining the contamination of toner when two-color printing is performed using the contact development method. figure,
FIG. 11 is a schematic cross-sectional view showing an example of a developing device using a non-contact developing method, FIGS. )～(D)
is a schematic explanatory diagram for explaining the principle of solving the occurrence of color mixture, FIG. 14 is a schematic perspective view of a laser scanner unit,
Fig. 15 (A) is an explanatory diagram showing the deviation in the scanning start point of the laser beam, Fig. 15 (B) is an explanatory diagram showing the mismatch in the scanning length of the laser beam, and Fig. 16 is an explanatory diagram showing the difference in the scanning start point of the laser beam.
A block diagram showing the interface, FIG. 17 is the LB
A schematic explanatory diagram showing signals between the P unit and the LBP interface, Fig. 18 is a block diagram showing an example of the print control section of the LBP unit, and Fig. 19 shows laser beam scanning in the print control section shown in Fig. 18. FIG. 20 is a timing chart illustrating the operation of correcting the deviation of the starting point; FIG. FIG. 22 is a detailed block diagram of the quaternary counter and selector of the print control unit shown in FIG. Figure 24 is the first. A schematic explanatory diagram of the second operation panel, FIG. 25 is a block diagram of the page memory address controller, FIG. 26 is a block diagram of the DMA controller, FIG. 27 is a block diagram of the image memory, and FIG. 28 is a block diagram of the scanner interface. 29 is a detailed block diagram of the image data processing section shown in FIG. 28, and FIGS. 30(A) and 30(B) respectively explain enlargement and reduction of data in the image data processing section. Fig. 30 (A) is a timing chart when writing to the line memory, Fig. 30 (B) is a timing chart when reading from the line memory, and Fig. 31 is a timing chart when writing to the line memory.
A block diagram of the interface, FIG. 32 is a schematic explanatory diagram explaining the image composition mode, FIG. 33 is a schematic explanatory diagram showing various information for specifying image extraction and image forming position,
FIG. 34 is a schematic explanatory diagram showing an example of a display requesting information for inputting the information shown in FIG. A schematic explanatory diagram illustrating the division designation mode of the image extraction area, FIG. 37 is a schematic explanatory diagram illustrating the mode for erasing the outline of the document, and FIG. 38 is a schematic explanatory diagram illustrating the mode for erasing the outline of the document. FIG. FIG. 39 is a schematic diagram illustrating a mode in which page numbers are attached to output sheets in the order in which they are output. DESCRIPTION OF SYMBOLS 1... Automatic document feeder, 50... Composite mode selection means, 56... Original sheet number input means, 110.120... Reading device, 300... Image forming means, 403.405... - Image memory, 404.406...Writing control means. Figure 6 Figure 8 (A) Figure 12 (B) CD) 1st (A) (C) CB) CD) Figure 36 TI
T3 Figure 37

Claims (3)

[Claims] (1) A reading device that digitally reads an image on a document, an image memory for storing the read image data, and the image data read by the reading device is stored in the image memory directly or after editing. In a digital image forming apparatus having a writing control means for writing and an image forming means for forming a document image on a sheet of paper based on image data stored in an image memory, combining multiple sheets of document images onto one sheet of paper. a composition mode selection means for selecting an image forming operation to be formed using a composite mode, and a manuscript number input means for inputting the number of manuscript sheets on which an image is to be formed on one sheet, and when the composition mode is selected, the Image data of a plurality of documents specified by the control of the input control means is stored in the image memory, and the image forming means forms images of the plurality of documents on one sheet of paper based on the contents of the image memory. A digital image forming apparatus characterized in that it outputs images. (2) The digital image forming apparatus according to claim 1, further comprising an automatic paper feeding device that automatically feeds original documents one by one to a reading device. (3) The digital image forming apparatus according to claim 1 or 2, wherein the image memory stores image data corresponding to an image reduced in size from the actual size of the original image.