JPH02210481A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent forgery of currency and security, etc., by stopping a part of the image forming device responding to the discrimination of a specified image in image formation. CONSTITUTION:The characteristics of the inputted image are extracted according to the algorithm fixed beforehand in a characteristic extracting circuit 103. This characteristic data and the image which is to be inhibited from copying are processed with the same algorithm and together with an already extracted specified image data 104 are compared and deliberated at a judging circuit 105, and the judged result (i) is inputted to an inputting port of a micro computer 301 or an interrupting electrode. The existence of a copying inhibited material is sensed by the micro computer 301 by watching the level of this inputting port or by the generation of the interrupting process. If it is judged that there is a copying inhibited material, a part or all parts of a driving device necessary for image formation is stopped by the micro computer 301. Thus specified images such as currency or securities can be prevented from being forged.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to an image forming apparatus for preventing counterfeiting of banknotes, securities, and the like.

[Prior Art] In recent years, with the spread of copying devices such as copying machines, an environment has been created in which copies can be easily made. In particular, with the development and release of full-color copying machines, the image quality of copied images has improved to a level that is indistinguishable from the original image with the naked eye, and it has become possible to make such copies in a short time with simple operations. I came.

[Problems to be Solved by the Invention] However, the ease with which such faithful copies can be obtained raises the risk that they may be misused to counterfeit items such as banknotes and securities that are socially prohibited from being copied. must be considered to increase.

An object of the present invention is to provide an image forming apparatus that can prevent such risks.

Means for Solving the Problem] In order to achieve the above-mentioned objects, the present invention provides means for recognizing a specific image among images to be formed, and an image forming apparatus that responds to the recognition of the specific image during image formation. It has a control means for stopping a part of the.

[Embodiment] In view of the above points, in the embodiment of the present invention described below, a copying machine is made to recognize a specific image of a banknote, a security, etc., and when the specific image is recognized during a copying operation, the copying machine is Disclosed is a device that prevents counterfeiting of banknotes, securities, etc. by controlling all or part of the copying process differently from normal control and, as a result, preventing copies of the image from being output correctly. However, the present invention is not limited to devices having a document reading section such as copying devices, but can also be applied to image forming devices in which a target image is given as an electrical signal and forms an image on a recording material such as paper. Of course it can be done.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Below, a full-color digital copying machine will be described as an example of an embodiment of the present invention.

FIG. 2 shows an overall configuration diagram of a full-color digital copying machine.

Reference numeral 201 is an image scanner section that reads a document and performs digital signal processing. Further, 202 is a printer unit, which prints out an image corresponding to the original image read by the image scanner unit 201 on paper in full color.

In the image scanner unit 201, reference numeral 200 denotes a mirror pressure plate, and an original 204 on an original table glass (hereinafter referred to as platen) 203 is irradiated with a lamp 205, and mirrors 206, 20
7, 208, an image is formed on a 3-line sensor (hereinafter referred to as CCI) 210 by a lens 209, and is sent to a signal processing unit 211 as full color information red (R), green (G), and blue (B) components. In addition, 205, 20
Reference numeral 6 indicates a speed V, and reference numerals 207 and 208 scan the entire surface of the document by mechanically moving in a direction perpendicular to the electrical scanning direction of the line sensor at 1/2v.

The signal processing unit 211 electrically processes the read signal and decomposes it into magenta (M), cyan (C), yellow (Y), and black (B k ) components.
Send to 2. Furthermore, for each document scan by the image scanner section 201, one component among M, C, Y, and Bk is sent to the printer section 202, and one printout is completed by scanning the document four times in total.

M, C, Y sent from the image scanner unit 201
Alternatively, the Bk image signal is sent to the laser driver 212. The laser driver 212 modulates and drives the semiconductor laser 213 according to the image signal. Laser light is polygon mirror 2
14. The photosensitive drum 217 is scanned through the f-θ lens 215 and the mirror 216.

Reference numeral 218 denotes a rotary developing device, which includes a magenta developing section 219, a cyan developing section 220 . It is composed of a yellow developing section 221 and a black developing section 222, and the four developing devices alternately contact the photosensitive drum 217 and develop the electrostatic latent image formed on the photosensitive drum 217 with toner.

223 is a transfer drum, and paper cassette 224 or 225
The paper fed from the transfer drum 223 is wound around the transfer drum 223, and the image developed on the photosensitive drum 217 is transferred onto the paper.

After the four colors M, C, Y, and Bk are sequentially transferred in this manner, the paper passes through the fixing unit 226 and is discharged.

FIG. 1 is a block diagram for explaining the image processing circuit and image forming sequence of the full-color copying machine shown in FIG. Contains circuitry for

A detailed explanation will be given using a block diagram of an apparatus according to an embodiment of the present invention with reference to FIG.

The microcomputer 301 has an input/output section and controls the entire machine. Output port 0. ~07
are each connected to a typical driver load required for image formation.

01 is connected to the tarock circuit 305 that generates a clock to drive the CCD 210, and depending on the state of 01, C0
The clock supplied to D210 can be stopped.

02 is connected to a lamp power source 304 for supplying power to the document illumination lamp 205, and the lamp can be controlled to 0N10FF depending on the state of 0□.

03 is connected to a motor driver 302 that controls a driving motor 303 of the reading optical system, and depending on the state of 03, an instruction to permit or prohibit driving can be given to the motor driver 302.

04 is connected to a high voltage power supply 313 for supplying high voltage power to the primary charger, and 04 is connected to the 0N10 of the power supply.
Can control FF.

05 is 1 at the developing position of the developing units 219 to 222.
High voltage power supply 3 for applying developing bias to two developing devices
11 and 0. By 0N10F of power supply
F can be controlled.

06 is connected to a high-voltage power supply 309 for supplying high-voltage power to the transfer charger 310.
N10FF can be controlled.

07 is a driver 30 for a drive motor 308 for conveying paper.
7 is connected. The drive motor 308 drives belts, rollers, etc. necessary for paper conveyance through various drive transmission systems.

Next, the image signal system will be explained.

The image of the document illuminated by the lamp 205 is captured by the optical system on the CCD 21. as explained in FIG. The image is formed on C3A2 and converted into electrical signals of each color of R, G, and B in synchronization with a clock signal generated by a clock circuit 305.

These electrical signals are amplified in block 101 and A/D
It is converted into a digital signal by a converter. The digital image signals R, G, and B are processed by the color processing circuit 102 through masking processing that performs color correction of CCD filters and developing toner.
Each toner amount signal C, M is subjected to color processing such as VCR processing.
, YBk. These toner amount signals are selected one by one by the selector 106 during the corresponding color scan, are input to the laser driver 212, and are sent to the laser 21.
3 to expose the photosensitive drum to form a latent image according to the signal.

At the same time, the digital image signals R, G, and B are processed by the characteristic extraction circuit 1.
03 is also input. This feature extraction circuit 103 extracts features of the input image according to a predetermined algorithm.

For example, feature extraction processing is performed by focusing on a specific pattern or color distribution of an input image. This characteristic data and the specific image data 104 extracted in advance by processing the image whose copying is to be prohibited using the same algorithm are used in the determination circuit 1.
05, the comparison result i is inputted to the input port or interrupt terminal of the microcomputer 301. The microcomputer 301 learns that there is a copy-prohibited item by monitoring the level of this input port or by generating an interrupt process. If it is determined that there is a copy-prohibited item, the microcomputer 301 stops driving some or all of the drive devices necessary for image formation.

For example, by controlling the signal 01 to stop the clock oscillation of the CCD clock circuit 305, the generation of the image signal can be stopped and copying can be prohibited.

Furthermore, if the lamp power source 304 is controlled by the signal 02 to turn off the lamp 205, the subsequent image signals can be equivalent to a black original.

If the driving of the reading optical system is stopped by controlling the signal 03, copying can be prohibited since the image signal of the stopped line will continue to be generated.

If the power supply to the charger is stopped at 1 o'clock by controlling the signal 04, no potential will be generated on the photosensitive drum thereafter, resulting in a solid image regardless of the developed color.

Signal 0. If the power supply to the developing device is stopped by controlling this, the latent image will no longer be developed.

If the power supply to the transfer charger is stopped by controlling the signal 06, the developed toner will no longer be transferred to the recording paper, so copying can be prohibited.

If the paper conveyance drive system is stopped by controlling signal 07, the subsequent image forming process will be stopped, and since paper jam detection is generally activated, all electrophotographic processes will be stopped.

Whether this part of the image forming apparatus should be stopped at this point is determined depending on the specificity of the apparatus. In this embodiment, an apparatus using an electrophotographic process has been described, but the present invention is not limited to this, and for example, in the case of an ink jet recording apparatus, the supply of ink and the power supply to the ink sheet may be stopped or shifted. Further, the portion to be stopped is determined in consideration of various factors. This is because stopping only a specific part may cause damage to the machine, and a device or combination of stopping devices must be selected that will not cause such damage.

In this way, if a feature that is the same as a predetermined pattern is detected in a read image during the copying process, part or all of the image forming device can be stopped immediately, thereby preventing the copying of banknotes, etc. can.

FIG. 3 shows a second embodiment of the invention. The difference from the first embodiment is that in this embodiment, the toner amount signal selector 106
The point is that the memory circuit 107 is provided after the memory circuit 107.

This is because in the first embodiment, image signal processing as an image forming process and specific pattern detection processing are performed simultaneously, so depending on the detection method, if it takes time to output the determination result, It is conceivable that the image formation of the specific pattern may be performed.

In such a case, the memory circuit 10 is installed before the laser driver.
7 to delay the image signal for a certain period of time, counterfeiting can be completely prevented. Here, the capacity of the memory is determined by the determination circuit 10 after the image data is input to the feature extraction circuit 103.
5, a capacity that can delay the output time of the determination result is required.

As explained above, according to this embodiment, a copying apparatus, particularly a full-color copying machine, is provided with means for recognizing specific images of banknotes, securities, etc., and image recognition processing is performed during the copying operation. If it is determined that all or part of the original is a specific image, for example, counterfeiting of banknotes, securities, etc. can be prevented by stopping part or all of the image forming device. .

[Effects of the Invention] As explained above, according to the present invention, specific images such as banknotes,
It is possible to prevent counterfeiting of securities, etc.

Figure 2 is a basic configuration diagram of a digital full-color copying machine.

FIG. 3 is a block diagram of the second embodiment.

211 is an image processing unit, 103 is a feature extraction circuit, 104 is a specific image data storage unit, 105 is a determination circuit, 107 is a memory circuit, 301 is a microcomputer, 210 is a CCD, 212 is a laser driver, 213 is a laser 309.31 .1,313 is high voltage power supply, 303.308
is a motor, 302 and 307 are motor drivers, and 9 to 222 are M.

C2 Y.

B]< developing device,

Claims (9)

[Claims] (1) Image formation characterized by having means for recognizing a specific image among the images to be formed, and a control means for stopping a part of the image forming apparatus in response to recognition of the specific image during image formation. Device. (2) The image forming apparatus according to claim 1, wherein the image forming apparatus to be stopped is a document illuminating device. (3) The image forming apparatus according to claim 1, wherein the image forming apparatus to be stopped is a drive device for a document reading optical system. (4) The image forming apparatus according to claim 1, wherein the image forming apparatus to be stopped is a driving device for a document reading sensor. (5) Claim (1) characterized in that the image forming device to be stopped is a photosensitive drum charging device for an electrophotographic process.
). (6) The image forming apparatus according to claim 1, wherein the image forming apparatus to be stopped is a developing apparatus for an electrophotographic process. (7) The image forming apparatus according to claim 1, wherein the image forming apparatus to be stopped is a transfer apparatus for an electrophotographic process. (8) The image forming apparatus according to claim 1, wherein the image forming apparatus to be stopped is a recording paper conveying apparatus. (9) The image forming apparatus according to claim (1), wherein the image forming apparatus has a buffer memory that delays the image for a period longer than the recognition time of the specific image.