JPH0774941A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent the generation of forgery by detecting cooking up on a specific original. CONSTITUTION:This image forming device is provided with a scanner unit 101 used as a picture reading means for reading picture data from an original and capable of varying the exposure angle of an exposing lamp (not shown), an image processing unit 102 for inputting the read color picture data consisting of R, G and B and applying known picture processing to the data, a printer unit 103 for recording color picture data on recording paper, and a specific original discriminating unit 105 for inputting picture data from the unit 101 and discriminating whether the original is paper money or a specific original such as securities. The unit 105 executes exposure plural times by changing the exposure angle, mutually compares picture data read out by the exposure of plural times to detect cooking up formed on the original, and at the time of detecting the cooking up, inhibits the operation of the unit 103. In addition, warning is outputted through an operation display part 104.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to image reading means for exposing a document placed at an exposure position to read image data,
The present invention relates to an image forming apparatus having an image recording unit that records read image data on recording paper.

[0002]

2. Description of the Related Art In recent years, due to improvements in image processing technology and image forming technology, it has become possible to perform image formation so finely that copy bills copied by a color copying machine and actual bills cannot be easily distinguished. For this reason, a device has been developed that discriminates special documents such as banknotes and securities, and prohibits illegal copying in the case of special documents. A device equipped with a function for discriminating special documents in a copying machine is also provided. Has been done.

In a device having such a special document discriminating function, as a method for discriminating a special document, for example, a method using a pattern matching method as disclosed in Japanese Patent Laid-Open No. 2-83571 "Image Recording Device" is used. It is common.
In this apparatus, it is determined whether or not the original is a special original based on the input image data and the pattern data registered in advance.

On the other hand, the special manuscript itself such as bills and securities is subjected to physical processing (work) which cannot be reproduced by copying in advance, so that the duplicated copy and the special manuscript can be distinguished. Measures are being considered. Further, in the near future, it is considered to add a unified mark to a bill to identify it as a bill, and to print the unified mark with some special work.

[0005]

However, according to the prior art, although it is possible to read the image of the original document and determine whether or not it is the special original document, the work performed on the special original document itself. Since it is not possible to detect such a problem, there is a problem that the work such as the unified mark cannot be used for the process of distinguishing the special document.

The present invention has been made in view of the above, and it is an object of the present invention to detect forgery of a special document and prevent forgery.

[0007]

In order to achieve the above object, the present invention exposes an original document placed at an exposure position to read image data, and image data read on a recording sheet. In an image forming apparatus having an image recording means for recording, the exposure angle varying means for varying the exposure angle of the image reading means and the image reading means and the exposure angle varying means are controlled to vary the exposure angle. When the control means for performing a plurality of exposures is compared with the image data read by the plurality of exposures to detect the workmanship provided on the document, and when the workmanship is detected by the workmanship detection means. In addition, the present invention provides an image forming apparatus including a prohibition unit that prohibits the operation of the image recording unit.

In order to achieve the above object, the present invention exposes a document placed at an exposure position to read image data, and image recording means for recording the read image data on a recording sheet. And a plurality of exposures in which the exposure angle is changed by controlling the exposure angle changing means for changing the exposure angle of the image reading means and the image reading means and the exposure angle changing means. The control means for performing the above-mentioned operation, the image data read by the plurality of exposures are compared, and the work detection means for detecting the work provided on the document; and the work when the work is detected by the work detection means. (EN) An image forming apparatus provided with a prohibiting unit that prohibits the operation of a recording unit and a warning unit that gives a warning when a work is detected by the work detecting unit.

It should be noted that the workmanship provided on the manuscript is a convex part due to the rise of ink or a concavo-convex part formed by processing the paper surface of the manuscript, and the workmanship detecting means changes the exposure angle. The work is detected based on the difference in the change in the reflected light between the convex portion or the concave-convex portion and the other portion that occurs.

Further, the work provided on the document is a glossy portion whose gloss is variable depending on the incident angle of light, and the reflected light of the glossy portion and other portions caused by changing the exposure angle is The work is detected based on the difference in change.

[0011]

The image forming apparatus of the present invention performs a plurality of exposures with variable exposure angles, compares the image data read by the plurality of exposures, detects the work provided on the document, and detects the work. In such a case, the operation of the image recording means is prohibited so that the image formation of the original document cannot be performed. Further, when the work is detected, the warning means gives a warning so that the user can recognize the special original.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The image forming apparatus of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram of the image forming apparatus according to the present embodiment, which is an image reading unit for reading image data from a document and also includes an exposure lamp 203.
(See FIG. 2) The scanner unit 101 whose exposure angle is variable, and the R read by the scanner unit 101
Input GB color image data, γ correction processing, RG
An image processing unit 102 that performs B / YMCBk conversion processing, gradation processing, etc., a printer unit 103 that records color image data after image processing by the image processing unit 102 on recording paper, input of various modes and messages Image data is input from the operation display unit 104 and the scanner unit 101 for displaying the
It is composed of a special document discriminating unit 105 for discriminating whether or not it is a special document such as securities, and a main control unit 106 for controlling the above-mentioned respective parts.

FIG. 2 shows the construction of the scanner unit 101, in which the contact glass 2 for placing the original 201 is placed.
02, an exposure lamp 203 which is a light source for exposing an original placed on the contact glass 202, and which is attached so that the exposure angle can be changed, and the reflected light of the light emitted from the exposure lamp 203 to the original will be described later. CCD sensor 20
8, the first mirror 204, the second mirror 205, the third
A mirror 206 and a lens 207 are provided, a CCD sensor 208 that receives reflected light, photoelectrically converts it, and inputs it as image data, and an exposure angle variable drive unit 209 for changing the exposure angle of the exposure lamp 203. .

In this embodiment, the scanner unit 1
When the color image data is read at 01, four scans are performed in the order of C, M, Y, and Bk. Also,
In addition to four scans of C, M, Y, and Bk, one scan is performed as a prescan. Furthermore, C, M, Y, Bk
In reading any one of the four colors (C color in this embodiment), one scan is performed to detect a special document while changing the exposure angle from that in the normal scan. Therefore,
It is assumed that 6 scans are performed on one document.

The operation of the above configuration will be described. Here, first, the principle of the detection of the special document work according to the present invention will be described. In the present embodiment, the work provided on the special original is a convex portion due to the rise of ink, an uneven portion formed by processing the paper surface of the original, and a gloss portion whose gloss is variable depending on the incident angle of light. Further, the work detection is performed based on the difference in the change in the reflected light between the work (convex portion, uneven portion or glossy portion) and other portions caused by changing the exposure angle.

FIGS. 3 (a) and 3 (b) show a method of detecting work when a special manuscript is provided with a convex part due to the rise of ink or an uneven part formed by processing the paper surface of the manuscript. . FIG. 11A shows the state of reflected light when scanning is performed with the exposure angle of the exposure lamp 203 set to the angle for normal image reading, and FIG.
Indicates the state of reflected light when scanning is performed with the exposure angle of the exposure lamp 203 further inclined relative to the angle during normal image reading. Generally, when the image is read by the scanner unit 101, the image surface of the original is uniformly flat,
It is premised that the irradiation light on the image surface is irradiated at a constant angle (exposure angle). On such a premise, since the reflectance of the reflected light changes depending on the lightness and darkness of the original image, the intensity of the reflected light is photoelectrically converted by the CCD sensor 208 and can be input as image data.

However, when the image surface of the original is not uniformly flat, the intensity of the reflected light at the non-flat portion, that is, the work (convex portion or uneven portion) is not only the light and shade of the original image, It greatly changes depending on the exposure angle of the irradiation light. Therefore, as shown in (a) and (b) of FIG.
By comparing the image data after photoelectric conversion (that is, the intensity of reflected light) input in two scans with different exposure angles, the part where the image data changes significantly is detected as a work (convex portion or uneven portion). can do.

FIGS. 4 (a) and 4 (b) show a method of detecting a work when a special document is provided with a gloss portion whose gloss varies depending on the incident angle of light. The figure (a) is
The state of the reflected light when scanning is performed by setting the exposure angle of the exposure lamp 203 to the angle at the time of normal image reading, and FIG. 6B shows the exposure angle of the exposure lamp 203 at the time of normal image reading. The following shows the state of reflected light when scanning is performed at an angle further than the angle of time. Irradiation light is diffusely reflected on the image surface of a normal document, but in the glossy part,
Most of the diffusely reflected light is reflected at the same angle as the incident angle. For this reason, when the exposure is performed at a tilt with respect to the normal exposure angle, the reflected light reaching the CCD sensor 208 from the glossy portion of the original is considerably reduced as compared with the normal change of the reflected light on the image surface of the original. Therefore, as shown in (a) and (b) of the figure, image data after photoelectric conversion (that is, the intensity of reflected light) input by two scans with different exposure angles.
By comparing the above, it is possible to detect a portion where the image data changes significantly as a work (glossy portion).

Next, referring to the flow chart of FIG.
A specific operation will be described. 9A is a flowchart of the scanning operation of the scanner unit 101, and FIG. 9B is a flowchart of the control operation of the special document discrimination unit 105. When a document is placed on the contact glass 202 and a copy start key (not shown) of the operation display unit 105 is pressed, the scanner unit 101
Performs a prescan to detect the document size and the like (S501). Next, a scan for reading the C color image data is performed, and the read image data is transferred to the image processing unit 102 and the special document discrimination unit 105 (S502), and subsequently, the exposure angle variable drive unit 209.
Is driven, the exposure angle of the exposure lamp 203 is made tight (increasing the inclination), scanning is performed for detection of the workmanship, and the read image data is used as the special document discrimination unit 1
It transfers to 05 (S503).

After that, the exposure angle of the exposure lamp 203 is returned to the original value, scanning for reading the image data of M color, Y color, and Bk color is performed, and the read image data is transferred to the image processing unit 102 ( S504 to S506),
The process ends.

On the other hand, the special document discriminating unit 105 has a C
When the color image data and the image data at the time of scanning for the crafting detection are input (S507, S508), these image data are compared based on the principle of the crafting detection of the special document described in FIGS. 3 and 4 ( S509), it is determined whether there is work (S510). If it is determined that there is no workmanship, the process ends. On the other hand, if it is determined that the document has been modified, a warning message indicating that the document cannot be copied is displayed on the operation display unit 105 (S5).
11), the image forming operation prohibition signal is output to the printer unit 103 (S512), and the process is terminated. It should be noted that the printer unit 103 stops the image forming operation when the prohibition signal of the image forming operation is input.

As described above, in the present embodiment, forgery can be prevented by detecting the workmanship of the special document. Also,
The detection of the special document modification can be performed at high speed because the determination can be made only by the image data comparison processing as described above. Further, in the present embodiment, the special document is determined only by the detection of the workmanship. However, for example, when the workmanship of the special manuscript of the present invention is detected and the workmanship is detected, further detailed pattern matching is performed. The special manuscript discrimination process may be executed, or may be executed simultaneously with another special manuscript discrimination process.

[0023]

As described above, the image forming apparatus of the present invention exposes the document placed at the exposure position to read the image data, and records the read image data on the recording paper. In an image forming apparatus having an image recording means, an exposure angle varying means for varying the exposure angle of the image reading means, and a plurality of exposure angle varying means for controlling the image reading means and the exposure angle varying means. Of the exposure means and the image data read by the plurality of exposures are compared to detect the workmanship provided on the document, and when the workmanship is detected by the workmanship detection means, Since it is provided with a prohibiting means for prohibiting the operation of the image recording means, it is possible to detect the work of the special document,
Anti-counterfeiting can be performed.

Since the warning is given by the warning means, the user can be notified of the reason why the image formation is impossible.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of an image forming apparatus of this embodiment.

FIG. 2 is an explanatory diagram showing a configuration of a scanner unit.

FIG. 3 is an explanatory view showing the principle of detection of a special original document.

FIG. 4 is an explanatory view showing the principle of detection of a special original document.

5A is a flowchart of a scanning operation of a scanner unit, and FIG. 5B is a flowchart showing a control operation of a special document discriminating unit.

[Explanation of symbols]

 101 Scanner Unit 102 Image Processing Unit 103 Printer Unit 104 Operation Display Unit 105 Special Original Discrimination Unit 106 Main Control Unit 203 Exposure Lamp 209 Exposure Angle Variable Drive Unit

Claims (4)

[Claims] 1. An image forming apparatus comprising: an image reading unit that exposes a document placed at an exposure position to read image data; and an image recording unit that records the read image data on a recording sheet. An exposure angle varying means for varying the exposure angle of the reading means; a control means for controlling the image reading means and the exposure angle varying means to perform a plurality of exposures with a variable exposure angle; A work detection unit that compares read image data and detects a work provided on the document, and a prohibition unit that prohibits the operation of the image recording unit when the work is detected by the work detection unit An image forming apparatus characterized by the above. 2. An image forming apparatus comprising: an image reading means for exposing a document placed at an exposure position to read image data; and an image recording means for recording the read image data on a recording sheet. An exposure angle varying means for varying the exposure angle of the reading means; a control means for controlling the image reading means and the exposure angle varying means to perform a plurality of exposures with a variable exposure angle; A modification detection unit that compares the read image data and detects modification provided on the document; a prohibition unit that prohibits the operation of the image recording unit when the modification is detected by the modification detection unit; An image forming apparatus, comprising: warning means for issuing a warning when a work is detected by the work detecting means. 3. The workmanship provided on the manuscript is a convex part due to a rise of ink or a concavo-convex part formed by processing the paper surface of the manuscript, and the workmanship detecting means is configured to change the exposure angle. 3. The work is detected based on a difference in change in reflected light between the convex portion or the concave-convex portion and other portions that occur.
The image forming apparatus described. 4. The work provided on the original is a glossy portion whose gloss is variable depending on the incident angle of light, and is a reflection of light reflected by the glossy portion and other portions caused by changing the exposure angle. The image forming apparatus according to claim 1, wherein the work is detected based on the difference in the change.