JP2002305641A - Image forming apparatus and image forming method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent a malicious user from invalidating a means for generating forgery prevention data by devising a mounting method of the means for generating forgery prevention data. A non-volatile memory stores additional data for preventing forgery.
The additional data generation unit 511 reads the additional data for preventing forgery from the non-volatile memory and generates a first digital signal sequence corresponding to the additional data when the image is formed. The first digital signal sequence is subjected to an exclusive OR operation with the second digital signal sequence corresponding to the image data, and the operation result is output to the laser driver IC 512. The laser driver IC drives the laser 403 based on the calculation result, and the laser forms a latent image for image formation. In particular, in the present invention, the additional data generator 51
1 and the laser driver IC 512 are arranged in at least the same unit so that the additional data
11 (disabling the function).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus and an image forming method, and more particularly to an image forming apparatus and an image forming method that contribute to preventing forgery of securities and the like.

[0002]

2. Description of the Related Art In recent years, image forming apparatuses such as printers, copiers, and facsimile machines have attracted attention for their ability to perform color printing, high-quality printing, and high-speed printing, and have been used by various users. For example, there is a color laser beam printer as one of the color image forming apparatuses, and a multicolor image is recorded by scanning a light beam on a photosensitive member in a main scanning direction.
After performing the above-mentioned phenomenon, the image is transferred to a recording medium such as a recording paper on a carrier, and is subjected to a predetermined process.

The technical improvement of these color image forming apparatuses has been remarkable and has spread rapidly. In particular, its image forming ability is excellent, and it is possible to reproduce a document image with extremely high accuracy.

On the other hand, the development of these technologies has caused problems such as forgery of banknotes and securities by malicious users and infringement of copyright.

As a method for dealing with this problem, there is a method of adding a specific pattern for preventing forgery to a formed image at a level that is difficult for human eyes to identify. In this method, first, when a digital signal sequence relating to image data is input, this digital signal sequence is superimposed on a digital signal sequence corresponding to the additional data (for example, yellow which is difficult to see), and the superimposed digital signal By inputting the columns to the driving unit and driving the image forming elements for image formation,
An additional image for preventing forgery is superimposed.

FIG. 9 shows a block diagram of an engine-side signal processing section for such an image forming apparatus. A VDO signal 6 sent from a printer controller (not shown)
It is sent to the laser drive circuit 901. The image mask signal generation unit 411 is a block that generates a MASK signal 419 that is a control signal for forcibly turning off the laser outside the printing area. The MASK signal 419 is set to “1” outside the print area, and set to “0” for the print area. The MASK signal 419 receives desired information from the CPU 412 and generates the MASK signal 419 based on the BD signal 423 and the PSYNC signal 424. The tracking pattern generation unit 902 is a block that the laser drive circuit 501 has and generates a signal for printing with yellow toner, which makes it difficult to see dots representing machine-specific numbers on printed matter. The code is represented by the arrangement of this tracking pattern on the printed matter. The tracking pattern generator 902 includes a crystal oscillator 413 disposed on the engine side.
Clock signal CCLK output from BD and BD signal 42
3. Upon receiving the PSYNC signal 424, a signal MKON for forcibly turning on the laser and a signal MKOFF for forcibly turning off the laser are generated. The signal MKON and the signal MKOFF correspond to V
The DO signal 6 is an asynchronous signal. Note that the CPU 412 provides the tracking pattern arrangement information 421 to the tracking pattern generation unit 902. The CPU 412 has a memory 420
Is read and coded, and the tracking pattern arrangement information 421 is generated.

[0007] The above-described tracking pattern generating section 902
Is a configuration added to the existing image forming apparatus,
It was added to the main board or connected to the main board by a cable.

[0008]

In the case described above, if the tracking pattern generation unit 902 is removed by a malicious user, the tracking pattern is not superimposed, and it is difficult to specify the device that formed the image. There is a problem of becoming.

Further, when the memory 420 storing the machine-specific number is replaced with another memory, there is a problem that a tracking pattern different from the original number is superimposed.

In view of the above, an object of the present invention is to provide an image forming apparatus which can more reliably superimpose a tracking pattern by making the above-mentioned tracking pattern generating section 902 difficult to remove.

Another object of the present invention is to make it difficult to replace the memory 420 storing the machine-specific number with another memory, and to more surely add the original machine number and the like to the formed image. It is an object of the present invention to provide an image forming apparatus capable of performing the above.

[0012]

In order to solve the above-mentioned problems, the present invention is an image forming apparatus for forming an image corresponding to input image data, and a storage means for storing predetermined additional data. Reading means for reading the additional data from the storage means; data generating means for generating a first digital signal sequence based on the additional data read by the reading means; Superimposing means for superimposing the first digital signal sequence on a second digital signal sequence corresponding to the image data, and driving for generating a drive signal based on the digital signal sequence superimposed by the superposing means Means, and an image forming means for generating a latent image for image formation based on a driving signal from the driving means, the driving means and the data generating means, To provide an image forming apparatus characterized by disposing at least the same unit.

The driving means and the data generating means may be integrated in the same integrated circuit, and the integrated circuit may be mounted on the unit.

Here, the additional data is data useful for preventing counterfeiting of securities or illegal duplication of a copyrighted work. For example, if the additional data is a number (machine number) unique to the image forming apparatus, Would help to track down the source of illegally formed images.

The superimposing means may perform an exclusive OR operation to superimpose a digital signal sequence related to the image data and a digital signal sequence based on the additional data.

Further, another storage means for storing the same additional data as the additional data stored in the storage means in the image forming apparatus, and the additional data stored in the storage means at the time of image formation. A determination unit that determines whether the data and the additional data stored in the other storage unit match, wherein the data generation unit determines that the two match, as a result of the determination by the determination unit. A configuration may be such that a first digital signal sequence is generated based on the additional data. With this configuration, it is possible to prevent not only the invalidation by removing the data generating means but also the removal and replacement of the additional data.

Also, as a result of the determination by the determination means,
If the additional data stored in the storage means does not match the additional data stored in the other storage means,
The configuration may be such that normal image formation is not performed.

The image forming apparatus is a color image forming apparatus that outputs a color image, and the image data includes at least data of yellow, cyan, and magenta colors, and the data generating unit includes: It is preferable that a digital signal sequence based on the additional data is generated only for a digital signal sequence of the image data for yellow.

Further, the present invention is an image forming apparatus for forming an image corresponding to input image data, wherein the first storage means stores predetermined additional data, and the first storage means. A second storage unit for storing the same additional data as the additional data stored in the image forming apparatus;
Reading means for reading the additional data respectively stored from the first storage means and the second storage means;
Determining means for determining whether the additional data read by the reading means match; and, as a result of the determination by the determining means, determining that the two match, a first digital signal sequence based on the additional data. Data generating means for generating the data, and the first data generated by the data generating means.
Superimposing means for superimposing the digital signal sequence of the above on a second digital signal sequence corresponding to the image data; driving means for generating a drive signal based on the digital signal sequence superimposed by the superimposing means; An image forming unit that generates a latent image for image formation based on a driving signal from the driving unit.

The present invention also relates to an image forming method for forming an image corresponding to input image data, wherein a step of reading predetermined additional data stored in a storage means, Generating a first digital signal sequence based on the additional data; and superimposing the generated first digital signal sequence on a second digital signal sequence corresponding to the image data;
Generating a drive signal based on the superimposed digital signal sequence; and forming a latent image for image formation based on the drive signal, wherein at least the step of generating the drive signal and the step of And a step of generating one digital signal in the same unit.

The present invention also relates to an image forming method for forming an image corresponding to the input image data, wherein the additional data stored in the first storage means and the second Reading the additional data stored in the storage means, determining whether the additional data stored in the first storage means matches the additional data stored in the second storage means, As a result of the determination, when it is determined that they match, a step of generating a first digital signal sequence based on the additional data, and a step of converting the generated first digital signal sequence into a first digital signal sequence corresponding to the image data. Superimposing on the two digital signal sequences;
An image forming method comprising: generating a drive signal based on a digital signal sequence after superimposition; and forming a latent image for image formation based on the drive signal.

It should be noted that, if it is determined by the above determination that there is no match, a step of stopping the image formation and a step of outputting a warning to the output means may be further provided.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [Common Embodiment] A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a sectional view showing a structure of an image forming apparatus A according to one embodiment of the present invention. In the image recording apparatus A, the sheet 102 fed from the sheet feeding unit 101 has its leading end held by the gripper 103f and is held outside the transfer drum 103. Then, the optical unit 10
The latent image formed for each color on the image carrier 100 by the developing unit 7 is developed by a developing unit (Dy, Dc, Dm, Db) for each color, and is transferred to a sheet held on the outer periphery of the transfer drum 103 a plurality of times. Thus, a multicolor image is formed.

Thereafter, the paper 102 is transferred to the transfer drum 103
The sheet is further separated and fixed by the fixing unit 104, and is discharged from the sheet discharge unit 105 to the sheet discharge tray unit 106. here,
Each of the developing units (Dy, Dc, Dm, Db) has a rotation support shaft at both ends thereof, and each is held by the developing unit selection mechanism unit 108 so as to be rotatable about the shaft. Further, each developing device (Dy, Dc, Dm, Db) is rotated for selecting the developing device in a state where its posture is kept constant. Then, after one of the selected developing units is moved to the developing position, the selection mechanism holding frame 109 is moved around the fulcrum 109b by the solenoid 109a, so that the developing unit selection mechanism 108 and the image carrier 100 of the developing unit
The direction of movement is determined.

Next, the operation of the image forming apparatus A having the above configuration will be described. First, the charger 111 shown in FIG.
Accordingly, the image carrier (photosensitive drum) 100 is uniformly charged to a predetermined polarity, and a first magenta latent image is formed on the photosensitive drum 100 by exposure with the laser beam L.

Next, in this case, a required developing bias voltage is applied only to the magenta developing device Dm to develop the magenta latent image, and the first toner image of magenta M is formed on the photosensitive drum 100. It is formed. On the other hand, the transfer paper P is fed at a predetermined timing, and immediately before the leading end thereof reaches the above-described transfer start position, the polarity is opposite to that of the toner (for example,
A transfer bias voltage (+1.8 KV) of a positive polarity is applied to the transfer drum 103 to transfer the first toner image on the photosensitive drum 100 to the transfer paper P, and the transfer paper P Electrostatically adsorbed on the surface. Thereafter, the remaining magenta toner is removed from the photosensitive drum 100 by the cleaner 112 to prepare for the formation of a latent image of the next color to be printed and the development process. Next, a second latent image of cyan is formed on the photoconductor drum 100 by the laser beam L, and the second latent image on the photoconductor drum 100 is developed by the developing unit Dc of cyan. A second toner image C is formed. Then, the second toner image of cyan C is transferred to the transfer paper P in accordance with the position of the first toner image of magenta M previously transferred to the transfer paper P. In the transfer of the second color toner image, immediately before the transfer paper reaches the transfer portion, the transfer drum 103 is transferred.
Is applied with a bias voltage of +2.1 KV. Similarly, third and fourth groove images of yellow and black are sequentially formed on the photosensitive drum 100, and are respectively sequentially developed by the developing units Dy and Db. Then, the position of the toner image is adjusted to the position of the toner image previously transferred to the transfer paper P, and the third and fourth toner images of yellow and black are sequentially transferred. As a result, four color toner images are formed on the transfer paper P in an overlapping state. These three colors, 4
In the transfer of the color toner image, +2.5 K is applied to the transfer drum 103 immediately before the transfer paper reaches the transfer portion.
V and a bias voltage of +3.0 KV are applied. The reason why the transfer bias voltage is increased each time the transfer of the toner image of each color is performed is to prevent a decrease in transfer efficiency.

The main cause of the decrease in the transfer efficiency is that when the transfer paper separates from the photosensitive drum 100 after the transfer, the surface of the transfer paper is charged to the opposite polarity to the transfer bias voltage by air discharge (the transfer paper is carried). This is because the charged electric charge is slightly accumulated on the surface of the transfer drum). This is because the charged electric charge is accumulated every transfer. When the transfer bias voltage is constant, the transfer electric field decreases every transfer. In the transfer of the fourth color, when the leading edge of the transfer paper reaches the transfer start position (including immediately before and immediately after), the AC voltage becomes 5.5 KV (effective value, the frequency of which is 500 Hz). The DC bias voltage +3.0 KV having the same polarity and the same potential as the transfer bias voltage applied at the time of transferring the toner image No. 4 is superimposed and applied to the charger 111.

The reason why the charger 111 is operated when the leading edge of the transfer paper reaches the transfer start position during the transfer of the fourth color is to prevent transfer unevenness. In particular, in the transfer of a full-color image, even if slight transfer unevenness occurs, it is easy to notice as a color difference, and it is necessary to apply a required bias voltage to the charger 111 to perform a discharge operation as described above. Becomes Thereafter, when the leading end of the transfer paper P on which the four color toner images are superimposed and transferred approaches the separation position, the separation claw 113 approaches and the leading end of the transfer drum 1 is moved.
The transfer paper P comes into contact with the surface of the transfer drum 103 and is separated from the transfer drum 103. Then, the leading end of the separation claw 113 keeps the contact state with the surface of the transfer drum until the rear end of the transfer paper P leaves the transfer drum 113, and then returns to the original position after being separated from the transfer drum 103. As described above, the charger 111 operates from the time when the leading end of the transfer paper P reaches the transfer start position of the final color until the rear end of the transfer paper separates from the transfer drum 103, and stores the accumulated charge (toner) on the transfer paper. (The opposite polarity to that of the transfer paper), thereby facilitating separation of the transfer paper by the separation claw 113 and reducing aerial discharge when the transfer paper is separated.

When the rear end of the transfer paper reaches the transfer end position (the exit of the nip formed by the photosensitive drum 100 and the transfer drum 103), the transfer bias voltage applied to the transfer drum 103 is turned off. (Installation potential). At the same time, the bias voltage applied to the charger 111 is turned off.

The transfer paper P thus separated is then conveyed to a fixing device 104, where the toner image on the transfer paper is fixed, and then discharged onto a discharge tray 115.

Next, the operation of laser beam scanning in the image forming apparatus A will be described. The optical unit 107 as a driving unit includes a semiconductor laser device 120 as an image forming element (light emitting element), a polygon mirror 121, a scanner motor 122, a lens 123, and a mirror 125.

Then, when the recording paper P is fed and the leading end thereof is detected, the image signal VDO for one page is output to the semiconductor laser device 120 in synchronization therewith. The light beam L is modulated by the image signal VDO and is emitted toward the polygon mirror 121 rotated by the scanner motor 122, and is guided to the photosensitive drum 100 by the lens 123 and the mirror 125. When the light beam L is emitted, the light beam L is detected by a detector (not shown) arranged on the scanning axis, and a beam detection signal BD serving as a horizontal synchronization signal is output. As a result, the light beam L
Accordingly, the photosensitive drum 100 is scanned and exposed in synchronization with the BD signal, and an electrostatic latent image is formed.

FIG. 2 is a block diagram showing a schematic configuration of a printing system using the image forming apparatus A. As shown in FIG. 1, the printer 2 (image forming apparatus A) includes a system 1 for expanding image information in a predetermined description language sent from the host computer 1, a printer control unit 404, and a signal processing unit 402. It is composed of a printer engine.

The host computer 1 also sends out bit data such as RGB read by an image reader or the like. The image processing unit 401 in the system 1 generates a VDO signal 6 as a 1-bit image data sequence by converting an RGB image into a YMCK image and performing pulse width modulation and dither processing on the data using the multi-valued image. I do.

FIG. 3 is an internal block diagram of the memory 1. As shown in the figure, an image developing unit 406 for converting printer language information sent from the host computer 1 into bitmap data, a page memory unit 407 for storing the data for one page, and RGB sent from the page memory unit
An image processing unit 401 converts information into YMCK information and generates a VDO signal 6 converted into a pulse width corresponding to the multi-valued density. The VDO signal 6 is one hard signal. The image processing unit 401 determines that the print dot is 600
It is controlled by a clock signal corresponding to one dot of Dpi.

FIG. 4 shows the VDO signal 6 sent from the memory 1.
7 is a time chart showing a BD signal 423 which is a horizontal synchronization signal sent from the engine to the printer controller, and a PSYNC signal 424 which is a vertical synchronization signal.
As shown in FIG. 4, in synchronization with the PSYNC signal 424, magenta data, cyan data, yellow data,
Output in the order of black data. [First Embodiment] In the present embodiment, in order to more reliably form additional data for preventing forgery, additional data is stored in two or more (of course, more) storage means, and an image is stored. The collation of the machine numbers is prevented by performing the collation of the two at the time of formation.

FIG. 5 shows an internal block diagram of the signal processing unit 402 on the engine side. The aforementioned printer controller 3
The VDO signal 6 sent from the DC controller 50
1 to the laser unit 510. The DC controller 501 includes a nonvolatile memory 503, and stores additional data. Also, the DC controller 50
A non-volatile memory 513 is provided outside the memory 1 and stores the same additional data as the non-volatile memory 503. The same additional data is written to the nonvolatile memories 503 and 513 by a memory writer at the time of manufacturing the main body. In addition,
When the main body is manufactured, the additional data may be stored in only one memory, and may be sequentially written to the other memory when the power of the main body is turned on.

The authentication of the main body number will be described with reference to the flowchart of FIG. First, the DC controller 50
1 reads the additional data stored in the nonvolatile memory 503 at the time of forming an image or the like (S50).
1). Further, the CPU 502 reads the additional data stored in the nonvolatile memory 513 (S502). It should be noted that both steps S501 and S502 may be executed in any order. The CPU 502 determines whether the additional data stored in the nonvolatile memory 513 matches the additional data stored in the nonvolatile memory 503 (S503). If the result of the determination is that they match, the CPU 502 executes an initialization sequence (S5).
04). By executing the initialization sequence, the additional data generator 511 reads the additional data stored in the nonvolatile memory 503 (or 513), and superimposes the additional data on the VDO signal output from the DC controller. The laser driver IC 512 drives the laser 403 based on the VDO signal on which the additional data is superimposed. For example, “0” is the switch 51 as the superimposed VDO signal.
4, the switch 514 is turned off. When the switch 514 is turned off, no current flows through the laser 403, so that the laser 403 cannot emit light. On the other hand, when “1” is input to the switch 514,
The switch 514 is turned on, a current flows through the laser 403, and the laser 514 emits light. Thus, an image is printed (S505).

On the other hand, in S503, the nonvolatile memory 5
13 and the non-volatile memory 53
If it is determined that the data does not match the additional data stored in 0, an error display command is issued to display an error on the CPU 502 or the panel. The panel displays an error in response to this command (S507). And C
The PU 502 stops the print sequence (S50
8).

Note that, instead of displaying the error, a predetermined warning sound may be generated from the audio output means.

Further, instead of stopping the printing sequence described above, it is also possible to control so as to form an abnormal image. For example, additional data for warning is stored in the above-mentioned nonvolatile memory. Then, when the above-described inconsistency occurs, the additional data generation unit 511 may select and read the additional data for warning, generate a corresponding digital signal sequence, and superimpose the digital signal sequence. .

As described above, according to the present embodiment, when one of the memories in which the additional data is stored is replaced by a malicious user, the image forming process is stopped. There is an advantage that forgery of securities and the like and illegal duplication of a copyrighted work can be prevented.

[Second Embodiment] In this embodiment, by providing the additional data generator 511 and the non-volatile memory 513 in the laser unit, the data generator 5 can be easily realized.
11 is designed to be unremovable to enhance the effect of preventing forgery.

FIG. 7 shows the configuration of this embodiment. The description of the operation is almost the same as that of the first embodiment, and will not be repeated.

In this embodiment, a non-volatile memory 513 storing additional data, an additional data generator 511 and a laser driver IC are provided in a laser unit 710. The laser unit 710 particularly includes the additional data generation unit 511 and the laser driver IC on the same substrate. Therefore, even if a malicious user attempts to remove the additional data generation section 511, the laser driver IC also comes off at the same time, so it is difficult to remove only the additional data generation section 511. That is, if the laser driver IC also comes off when the additional data generation unit 511 is removed, the laser cannot be driven, and the image formation by the present image forming apparatus is no longer possible.

As described above, in the present embodiment, by disposing the additional data generator 511 on the same substrate as the laser driver IC, it is possible to avoid removal of only the additional data generator 511. Can be added more reliably.

[Third Embodiment] In this embodiment, the laser driver IC in the laser unit is provided with the additional data generator 511, so that the data generator 511 cannot be easily removed. It is intended to enhance the effect of preventing forgery.

FIG. 8 shows the configuration of this embodiment. The description of the operation is almost the same as that of the first embodiment, and will not be repeated.

In this embodiment, the additional data generator 511 and the laser driver IC 8
12 is incorporated. In particular, the laser driver IC 812 includes an additional data generation unit 511 in addition to a normal laser driving function. That is,
It can be said that it was made into one chip. Therefore, if the malicious user removes the additional data generation unit 511, it means that the laser driver IC 812 is also removed at the same time.
It is impossible to remove only the additional data generation unit 511. If it is removed, the laser cannot be driven, and image formation by the present image forming apparatus is no longer possible.

As described above, in the present embodiment, the removal of only the additional data generator 511 is technically avoided by forming the additional data generator 511 into one chip in the laser driver IC 812. This allows
Additional data for preventing forgery can be added more reliably.

[0051]

[Other Embodiments] Even if the present invention is applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), an apparatus (for example, a copy Machine, facsimile machine, etc.).

Further, an object of the present invention is to provide a storage medium (or a recording medium) recording software program codes for realizing the functions of the above-described embodiments to a system or an apparatus, and to provide a computer (a computer) of the system or the apparatus. Or a CPU or MPU) reads out and executes the program code stored in the storage medium,
Needless to say, this is achieved. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.
In addition, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also based on the instructions of the program code,
The operating system (OS) running on the computer performs part or all of the actual processing,
It goes without saying that a case where the function of the above-described embodiment is realized by the processing is also included.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that a CPU or the like provided in the function expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

When the present invention is applied to the storage medium, the storage medium stores program codes corresponding to the flowchart shown in FIG. 6 described above.

[0055]

As described above, in the image forming apparatus of the present invention, the tracking pattern can be more reliably superimposed by making the above-mentioned tracking pattern generating portion difficult to remove.

In the image forming apparatus according to the present invention, the memory storing the machine-specific number is hardly replaced, and the original machine number and the like can be added to the formed image more reliably.

With these configurations, forgery of securities and the like can be more reliably prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of a structure of an image forming apparatus A according to a common embodiment.

FIG. 2 is a block diagram illustrating a schematic configuration of a print system using an image forming apparatus A.

FIG. 3 is a block diagram of the printer controller 3;

FIG. 4 shows a VDO signal 6, a BD signal 4 which is a horizontal synchronization signal.
23 is a time chart of a PSYNC signal 424 as a vertical synchronization signal.

FIG. 5 is a block diagram of a signal processing unit 402 on the engine side.

FIG. 6 is a flowchart of a body number matching process.

FIG. 7 is an internal block diagram of a signal processing unit 402 according to the second embodiment.

FIG. 8 is an internal block diagram of a signal processing unit 402 according to the third embodiment.

FIG. 9 is a block diagram of an engine-side signal processing unit according to the related art.

[Explanation of symbols]

 3 Printer controller 501 DC controller 502 CPU 503 Non-volatile memory 510 Laser unit 403 Laser 511 Additional data generation unit 512 Laser driver IC 513 Non-volatile memory 514 Switch

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 21/04 G03G 21/00 550 5C077 G06T 1/00 500 B41J 29/00 Z H04N 1/40 H04N 1 / 40Z F term (reference) 2C061 AP03 AP04 AQ06 AR01 BB15 BB35 CL10 JJ04 2H030 AD11 BB02 BB24 2H134 NA20 NA22 NA24 5B057 AA11 CA01 CA08 CA12 CA16 CB01 CB08 CB12 CB16 CC01 CE08 CH08 5C076 AA14 BP02 PP06 PP06

Claims (16)

[Claims] 1. An image forming apparatus for forming an image corresponding to input image data, comprising: storage means for storing predetermined additional data; read means for reading the additional data from the storage means; Data generating means for generating a first digital signal sequence based on the additional data read by the reading means; and the first digital signal sequence generated by the data generating means corresponding to the image data Superimposing means for superimposing on the second digital signal sequence to be driven, driving means for generating a drive signal based on the digital signal sequence superimposed by the superimposing means, and image forming based on the drive signal by the driving means. Image forming means for forming a latent image for the image forming apparatus, wherein at least the driving means and the data generating means are arranged in the same unit. An image forming apparatus. 2. The image forming apparatus according to claim 1, wherein said driving means and said data generating means are integrated in the same integrated circuit, and said integrated circuit is mounted on said unit. . 3. The image forming apparatus according to claim 1, wherein the additional data is data useful for preventing forgery of securities or illegal duplication of a copyrighted work. 4. The image forming apparatus according to claim 3, wherein the additional data is a number unique to the image forming apparatus. 5. An image forming apparatus according to claim 1, wherein said image forming means is a light emitting element. 6. The apparatus according to claim 1, wherein said superimposing means superimposes a digital signal sequence based on said image data and a digital signal sequence based on said additional data by executing an exclusive OR operation. The image forming apparatus as described in the above. 7. An additional storage device for storing the same additional data as the additional data stored in the storage device, and the additional data stored in the storage device during image formation. A determination unit that determines whether the additional data stored in the storage unit matches the data. The data generation unit, based on the additional data, determines that the two match, as a result of the determination by the determination unit. The image forming apparatus according to claim 1, wherein the first digital signal sequence is generated. 8. The image forming apparatus according to claim 7, wherein said storage means and said other storage means are nonvolatile memories. 9. If the result of the determination by said determination means is that the additional data stored in said storage means does not match the additional data stored in said other storage means, normal image formation is not performed. The image forming apparatus according to claim 7, wherein: 10. The image forming apparatus is a color image forming apparatus that outputs a color image, and the image data includes at least data of yellow, cyan, and magenta colors. The image forming apparatus according to claim 1, wherein a digital signal sequence based on the additional data is generated only for a digital signal sequence of the image data related to yellow. 11. An image forming apparatus for forming an image corresponding to input image data, comprising: first storage means for storing predetermined additional data; and first storage means for storing predetermined additional data. A second storage unit for storing the same additional data as the additional data, and a reading unit for reading out the additional data stored in the first storage unit and the second storage unit when the image is formed. Determining means for determining whether the additional data read by the reading means match; and determining that the two match, as a result of the determination by the determining means, a first digital signal based on the additional data. A data generating means for generating a sequence, and superimposing the first digital signal sequence generated by the data generating means on a second digital signal sequence corresponding to the image data Tatami means, driving means for generating a drive signal based on the digital signal sequence superimposed by the superimposing means, image forming means for forming a latent image for image formation based on the drive signal by the driving means, An image forming apparatus comprising: 12. The image forming apparatus according to claim 11, wherein said driving means and said data generating means are integrated in the same integrated circuit, and said integrated circuit is mounted on said unit. . 13. An image forming method for forming an image corresponding to input image data, comprising: a step of reading predetermined additional data stored in a storage means; and a step of reading the additional data based on the read additional data. Generating a first digital signal sequence by using the first digital signal sequence, and superimposing the generated first digital signal sequence on a second digital signal sequence corresponding to the image data. Generating a drive signal based on a digital signal sequence; forming a latent image for image formation based on the drive signal; and generating at least the drive signal and the first digital signal. Generating an image signal in the same unit. 14. An image forming method for forming an image corresponding to input image data, comprising the steps of: storing an additional data stored in a first storage unit and a second storage unit in an image formation; Reading the stored additional data; determining whether the additional data stored in the first storage means matches the additional data stored in the second storage means; and Generating a first digital signal sequence based on the additional data when it is determined that the two data coincide with each other; and converting the generated first digital signal sequence into a second digital signal corresponding to the image data. Superimposing on a column, generating a drive signal based on the digital signal sequence after superimposition, and forming a latent image for image formation based on the drive signal. An image forming method comprising: 15. The image forming method according to claim 14, further comprising a step of stopping image formation when it is determined that the images do not match. 16. The image forming method according to claim 14, further comprising a step of outputting a warning to an output unit when the judgment is a mismatch.