JPH06141137A - Picture processor - Google Patents

Abstract

PURPOSE:To discriminate surely a specific original by providing a lighting means emitting a light including an exciting light of a specific wavelength to an original and a means detecting a light of a wavelength toward the shorter wavelength than the specific wavelength in the reflected light from the original in the processor. CONSTITUTION:A light source 230 on which LEDs emitting an infrared ray (main wavelength 970nm) to an image scanner section 201 are arranged in an array employing an infrared ray as an exciting light and employing a visual light as a luminescent light is arranged. A halogen lamp 205 is extinguished and the light source 230 is lighted, an infrared fluorescent signal is read, and the reflected light is read by a G (green) line CCD sensor 210-2 in the read mode. When an exciting light of a specific wavelength such as an infrared ray is emitted to an original, a pattern is printed out by using ink having a characteristic lighted toward the shorter wavelength. An original whose copy is inhibited or the like is detected by reading a signal with a sensor having the sensitivity for the short wavelength band without giving effect on the actual operating state of the visual light.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus having a function of discriminating a specific original.

[0002]

2. Description of the Related Art Conventionally, various methods have been devised for recognizing a specific original.

Further, there has been proposed a method of recognizing that a pattern of a document is formed by a line drawing and a color tone of the image document.

In addition, a specific mark may be printed with fluorescent ink that reflects visible light by irradiating the specific original document itself with ultraviolet light to enable discrimination between the genuine product and the copied product based on the presence or absence of fluorescence of the printed product. is there.

[0005]

However, when these are applied to, for example, a copying machine, it is difficult to detect a specific original at an arbitrary position on the original plate of the copying machine and at an arbitrary angle, and as a result, copying is performed. There was a problem that it was difficult to prevent.

Further, even if the line drawing information or the tint of the original is detected, it cannot be said that there are no originals having the same characteristics as the specific originals, and there is a possibility that the general original is erroneously determined as a copy-inhibited original. was there.

Further, even if it is found that the product is a copy by observing the presence or absence of fluorescence, the copying act itself cannot be prevented.

In view of the above problems, it is an object of the present invention to provide an image processing apparatus for surely discriminating a specific original.

Further, according to the present invention, when determining a specific original,
Another object is to provide an efficient discrimination method.

Another object of the present invention is to rationalize the device configuration in discrimination.

A further object of the present invention is to provide a method of discriminating a specific original based on information other than the visible information of the original.

Other objects and aspects of the present invention will become apparent from the following detailed description of the invention.

[0013]

In order to solve the above-mentioned problems, the image processing apparatus of the present invention includes an illumination means for irradiating an original containing excitation light of a specific wavelength, and a reflected light from the original. And a unit for detecting light having a wavelength shorter than the specific wavelength.

[0014]

EXAMPLE 1 The present invention will be described below based on a preferred example.

In the following embodiments, a copying apparatus is shown as an application example of the present invention, but it is not limited to this, and it is needless to say that it can be applied to various other apparatuses such as an image scanner connected to a computer.

Further, in the following embodiments, as an application example,
Infrared light as excitation light will be described as visible light as emitted light, but if the wavelength of the emitted light is shorter than the wavelength of the excitation light, infrared light, visible light, or ultraviolet light in any band It goes without saying that it doesn't matter.

FIG. 2 shows an external view of the apparatus according to the first embodiment of the present invention.

In FIG. 2, reference numeral 201 denotes an image scanner section, which is a section for reading a document and performing digital signal processing. A printer unit 202 is a unit that prints out an image corresponding to the original image read by the image scanner 201 on paper in full color.

In the image scanner unit 201, 20
Reference numeral 0 is a mirror-thick plate, and a platen glass (hereinafter, platen)
The original 204 on 03 is illuminated with the light of the halogen lamp 205. The reflected light from the document is guided to the mirrors 206 and 207, passes through the infrared cut filter 208, and passes through the lens 209.
Then, an image is formed on a 3-line CCD sensor (hereinafter referred to as CCD) 210 and sent to the signal processing unit 211 as full color information red (R), green (G) and blue (B) components. Note that 205 and 206 are speed v, and 207 is 1
The / 2v line sensor mechanically moves in the vertical direction (hereinafter, sub-scanning direction) with respect to the electrical scanning direction (hereinafter, main scanning direction) to scan the entire surface of the document.

A light source 230 in which LEDs for emitting infrared light (main wavelength 970 nm) are arranged in an array is arranged.

The signal processing unit 211 electrically processes the read signal, decomposes it into magenta (M), cyan (C), yellow (Y), and black (Bk) components, and sends them to the printer unit 202. . In addition, the image scanner unit 201
M, C,
One component of Y and Bk is sent to the printer 202,
One print is completed by scanning the originals four times in total.

The M, C, Y, and Bk frame-sequential image signals sent from the image scanner unit 201 are sent to the laser driver 212. The laser driver 212 modulates and drives the semiconductor laser 213 according to the image signal. The laser light scans the photosensitive drum 217 via the polygon mirror 214, the f-θ lens 215, and the mirror 216.

Reference numeral 218 denotes a rotary developing device, which includes a magenta developing device 219, a cyan developing device 220, and a yellow developing device 22.
1. The four developing devices are alternately in contact with the photosensitive drum, and the M, C, Y, and Bk electrostatic latent images formed on the photosensitive drum 217 are developed with the corresponding toners.

Reference numeral 223 is a transfer drum, which is a paper cassette 22.
4 or 225, the paper fed from this transfer drum 2
The toner image developed on the photosensitive drum 217 is transferred to a sheet by winding the sheet around the sheet 23.

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

FIG. 11 shows the structure of the CCD 210 used in this embodiment. Here, 210-1, 210-2, 210
-3 is a light receiving element array for reading the R, G, B wavelength components in order.

The three light-receiving element arrays having different optical characteristics are arranged on the same silicon chip so that the R, G, and B one-line sensors are arranged in parallel with each other to read the same line of the original. It is configured monolithically.

FIG. 11B shows an enlarged view of the light receiving element.
Each sensor has a length of 10 μm per pixel in the main scanning direction. Each sensor can read the A3 original in the lateral direction (297 mm) with a resolution of 400 dpi.
There are 5000 pixels in the main scanning direction. The distance between the lines of the R, G, and B sensors is 80 μm, and 400 lpi
8 lines apart from each other in the sub-scanning resolution.

R, G, B from 210-1 to 210-3
Each sensor has an opening of 10 μm in the sub-scanning direction.

In each line sensor, an optical filter is formed on the sensor surface in order to obtain predetermined spectral characteristics of R, G, and B.

The spectral characteristics of the R, G, B line sensors of the CCD 210 will be described.

FIG. 18 shows R, G, and
This is the characteristic of the B filter.

As can be seen from this figure, the conventional R,
The G and B filters are sensitive to infrared light of 700 nm or more, but the infrared cut filter 208 arranged immediately before the lens 201 has the spectral characteristic shown in FIG. As a result, infrared light of about 700 nm or more is cut out of the spectral characteristics.

In the following, in the present embodiment, as an example of a copy-inhibited document whose copying should be prohibited, as shown in FIG. 1, a red stamp is applied to a predetermined portion of the document with ink having an infrared-exciting phosphor characteristic with respect to infrared rays. Although it is assumed that the same mark is printed on the original, the present invention is not limited to such an object.

Here, the infrared-excited phosphor will be described. The infrared-excited phosphor is classified as follows according to the mechanism.

(1) Multi-stage energy transfer (2) Infrared photostimulation effect is used (1) Infrared light is applied to transfer visible energy by two-stage or three-stage energy transfer. Is obtained. (2) is to generate luminescence of visible light by irradiating light of short wavelength in advance and then irradiating infrared light.

In the present embodiment, the multistage energy transfer of (1) is used. Specifically, BaY1.34Yb
A phosphor compound having 0.60 Er0.06F8 was used.

FIG. 12 shows the LED 23 used in this embodiment.
An emission spectrum B of 0 and an excitation spectrum A of the phosphor used in this example are shown.

FIG. 13 shows the emission spectrum of the phosphor used in this example.

As can be seen from the fluorescence emission spectrum, 5
It has a peak at 45 nm, and this reflected light is read by a G (green) line sensor. The G sensor reads because G is closest to ND.

In general, the intensity of fluorescence is less than half that of the excitation light and may be about 10% or less. In this embodiment, when the infrared fluorescence signal is read, the moving speed of the reader optical system is slowed to increase the charge storage time of the CCD and secure the dynamic range of the fluorescence light read signal.

[Image Scanner Unit] FIG. 3 shows an internal block of the image scanner 201. 210-1, 21
Reference numerals 0-2 and 210-3 denote CCDs having spectral sensitivity characteristics of red (R), green (G), and blue (B), respectively, and a signal quantized to 8 bits from 0 to 255 is output.

Sensor 210 used in this embodiment
Since -1, 210-2, and 210-3 are located at a distance as shown in FIG. 2, the spatial displacements of the delay elements 401 and 402 are corrected. 403,
Reference numerals 404 and 405 are composed of a log converter and a look-up table ROM, and the luminance signal is converted into a density signal. 406 is a known masking and UCR circuit,
Although detailed description is omitted, Y, M, C, and Bk signals for output are sequentially output with a predetermined bit length, for example, 8 bits, for each reading operation by the input three primary color signals. Reference numeral 407 is an OR gate circuit,
The value held in 8 is logically ORed. Normally, 00H is written in the register 408, and the output of 406 is directly output to the printer unit. However, in the forgery prevention process, the CPU 417 sets FFH in the register 408 via the data bus. As a result, an image filled with toner can be output. In addition,
As the anti-counterfeiting process, in addition to such image data change, various processes such as turning off the power of the apparatus and stopping the image forming process means are conceivable.

A CPU 417 controls the apparatus in each mode. A window comparator 408 determines whether or not a specific level signal instructed by the CPU 417 has been input, and in the above-mentioned infrared fluorescence reading mode, a red stamp emitting infrared fluorescence is detected.

The blow processing circuit 409 performs 16 × 16 block processing, and processes the output of the window comparator 408 for each 16 × 16 block.

Reference numeral 412 is a readable / writable random access memory (RAM), the data of which is switched by the selector 411 and the address of which is switched by the selector 413.

On the other hand, 419 is a main scanning counter, which has an H
It is reset by the SYNC signal and counted up at the timing of the CLK signal to generate 13-bit main scanning addresses (hereinafter X addresses) X12 to X0.

Reference numeral 420 is a sub-scanning address counter,
It is reset in the "0" section of the VSYNC signal and HSNC is reset.
It is counted up at the timing of the Y signal, and 13-bit sub-scanning addresses (Y addresses) Y12 to Y0 are generated.

The CPU 417 selects the selectors 411, 413, 415, 416 and the address decoder 4 according to each mode.
14 is read and written to and read from the RAM 412. 418 is an R added to the CPU 417
AM / ROM. A watermark detection circuit 410 detects a watermark portion of a bill.

FIG. 4 shows the window comparator 408 of FIG.
It is a block diagram of. 601, 602, 603, 60
A desired value is written in 4, 605, and 606 by the CPU 417.

607, 608, 609, 610, 61
Reference numerals 1 and 612 are comparators, which are A for inputs A and B.
The output becomes 1 only when> B is satisfied.

An AND gate 613 outputs 1 only when the outputs of all the comparators become 1, and outputs 0 otherwise. Now, registers 601, 60
2, 603, 604, 605, 606 respectively RH,
When the values RL, GH, GL, BH, BL are written, RL <R <RH and GL <G <GH and BL <B <BH are all established for the input signals R, G, B. Only when the window comparator 40
The output of 8 is "1", and otherwise it is "0".

FIG. 5 is a diagram showing the internal details of the block processing circuit 409 of FIG.

701, 702, 703, ..., 714, 7
Reference numeral 15 is a D flip-flop (hereinafter referred to as DFF), which is arranged in series with 15 pieces, and uses an input signal as a pixel clock CLK.
The signals are sequentially delayed, and VE = "0", that is, cleared to "0" in the non-image section.

Reference numeral 738 is an up / down counter of 5 bits, 737 is an OR gate, and 740 is an AND gate. The operation is based on the following table.

[0056]

[Table 1] That is, the output of the counter 738 is VSYNC or V
E is cleared to 0 in the section of "0", and Xt = Xt-15
When Xt = 1 and Xt−15 = 0, it is counted up, and when Xt = 0 and Xt−15 = 1, it is counted down. That is, as a result, the total sum (number of 1) of 16 data of Xt to Xt-15 is output. Furthermore, the output is passed through the DFF 739, and the FIFO memories 721, 722, 7 of one line unit are output.
Data of 16 lines are simultaneously input to the adder 741 by 23, ..., 734, 735, and the total sum thereof is output. As a result, the sum SUM of the number of 1's in the 16 × 16 window is output from 0 to 256.

Reference numeral 742 is a digital comparator, which compares the output SUM of the adder 741 with the comparison value TW predetermined by the CPU 417, and outputs the result as "0" or "1".

Therefore, by setting an appropriate number in TW in advance, noise removal can be performed in 16 × 16 block units.

FIG. 6 is a diagram for explaining the watermark detection circuit 410.

819, 820, ..., 821 are 18 F's.
IFOs, each with a delay of 1 line, 19 lines being processed simultaneously.

801, 802, 803, ..., 804, 8
05,806,807, ..., 808, ..., 809,81
0, 811, ..., 812, ..., 813, 814, 81
Numerals 5, ..., 816 are DFFs arranged in series for each of the outputs of 19 lines, and numeral 817, 81
Reference numeral 8 is a DFF which is further arranged in series after the DFF 812 in 9 units, and all the DFFs are driven by CLK16. Via AND gates 823, 824, 825,
DFF 804, 808, ..., 812, 816 (vertical 19
Block) and DFFs 809, 810, 811, 81
When the outputs of 2,817,818 (horizontal 19 block) are all "1", 1 is output, and Po at that time is output.
The position is latched and sent to the CPU.

FIG. 7 is a block diagram of the address decoder 414.

901, 902, 903, 904, 90
Reference numerals 5, 906, 907, 908, and 909 are registers directly connected to the CPU data bus, and desired values are written by the CPU.

Since all of 910, 911, 912 and 913 have the same structure, only 910 will be described.

914 and 915 are subtractors, which have inputs A,
AB is output for B, the output MSB is a sign bit, and when it becomes negative, MSB = 1 is output. Reference numerals 916 and 917 denote comparators having inputs A and B.
On the other hand, when A <B, “1” is output. However, when the MSB of A is "1", "0" is output regardless of the input of B.

918, 919, and 920 are ANDs, respectively.
When a value of BXY is written in the register 909 as a result, RX1 <X address <RX1 + BXY and RY1 <Y address <RY1 + BXY (1) only holds: X1 = X address−RX1 Y1 = Y-address-RY1 E1 = 1 is output. Similarly, in 911, X2 = X address-RX2 Y2 = Y address-RY2 E2 = 1 is output only when RX2 <X address <RX2 + BXY and RY2 <Y address <RY2 + BXY ... (2). Similarly, at 912, X3 = X address-RX3 Y3 = Y address-RY3 E3 = 1 is output only when RX3 <X address <RX3 + BXY and RY3 <Y address <RY3 + BXY ... (3). Similarly, in 913, X4 = X address-RX4 Y4 = Y address-RY4 E4 = 1 is output only when RX4 <X address <RX4 + BXY and RY4 <Y address <RY4 + BXY ... (4).

Reference numerals 914, 915, 916, and 918 denote OR gates, respectively, which satisfy the conditions (1), (2), (3), and
(4) RX1, RY so that two or more are not established at the same time
1, ... When RX4 and RY4 are set, 914
, X4 is output from the device 917, “1” is output from the device 917 when any condition is satisfied, and Y1, Y2, ..., Y4 is output from the device 918.
One of them is output. See also 915,916
The output is from the following table.

[0068]

[Table 2]

[Processing Flow] FIG. 14 shows a processing flow under CPU control. In FIG. 14, the start button is pressed at 11201, first the halogen lamp 205 is turned on at 11202, the reading optical system is moved without attaching the infrared LED, and the document size detection, the document angle detection, and the document color detection are performed. In addition, the rough position of the watermark portion in the document is detected. Therefore, the CPU causes the window comparator 408 to set the registers 601 to 6 shown in FIG. 4 to values that enable the background of the bill to be detected.
Write to 06.

FIG. 1 shows a state in which a specific document is placed on the platen. In the 1st scan, that is, in mode 1, the output of the window comparator is "" in the shaded portion in FIG. 1, that is, in the watermark and the peripheral portion. 1 ”.

Further, in the watermark portion, this is vertical /
Since a certain number of pixels continue horizontally, the portion corresponding to (Xc, Yc) in FIG.
The address corresponding to Yc) is latched and sent to the CPU.

The CPU is the center of the original (Xc, Yc)
You can get a rough idea of the value of. Next, the setting for the back direction scan 1120 in FIG. 14 is performed.
That is, the selector 411 is set to A, the selectors 413 and 415, 416 are set to the A side, and the address decoder 414 is set so that the position of the red mark is RX1 = Xs1 RY1 = Ys1 (one pixel unit). It

Here, Xc and Yc are data of the central position of the mark in the detection range of 9.5 mm, as described in the description of the detection circuit of FIG.

In order to sufficiently cover the range of the fluorescent mark having a diameter of 10 mm to 20 mm, the number of pixels corresponding to about 30 mm (472 at 400 dpi) is set in BXY.

The head addresses Xs1 and Ys1 are 15 mm from Xc and Yc (236 at 400 dpi).
The value from the origin is set for the number of pixels.

Next, after the reading optical system is shifted to one side, 1
In 1203, when the reading optical system is moved to the back direction after the reading optical system is moved to the back direction, the optical system is moved to the back direction.
The halogen lamp 205 is turned off, the infrared LED 230 is turned on, and the infrared fluorescence signal reading mode is performed.

As can be seen from the emission spectrum characteristics of FIG. 13, the fluorescence signal was read by the G (green) CCD signal.

The output of the window comparator 408 is output to the RAM 412 at four positions which are considered to be the positions marked with red in FIG.
Written in.

Further, in 1007, a red stamp is detected by an algorithm to be described later, it is determined in 11205, and if there is no possibility of forgery, that is, if the red stamp is not detected, in 11206, Y, It is developed with four color toners of M, C, and Bk, and fixed and output.

On the other hand, if it is determined at 11204 that there is a possibility of forgery, that is, if a red stamp is detected, at 11205, forgery prevention measures are taken. Specifically, by setting FFH in the register 408 of FIG. 3 (usually 00H is set), FFH is sent to the printer unit, Bk toner adheres to the entire surface, and a copy is made. become unable.

[Pattern Matching] Next, 11207
The pattern matching of the red stamp will be described in detail.

Two red-marked patterns are registered in advance when performing pattern matching.

When the specific portion of the specific original is written in the RAM 412, the CPU 417 then refers to the contents of the RAM 412 to perform the pattern matching operation. A flow chart of pattern matching is shown in FIG. Four kinds of binarized data are stored in the RAM 412 as candidates for the specific portion.
This is named area 1 to area 4.

First, the processing after 2102 is performed on the area 1. At 2102, window processing for noise removal is performed.

Assume that the binary image of area 1 is 2201. Here, it is assumed that a small square represents one pixel, a blank pixel is a white pixel, and a hatched portion is a black pixel. 220 this
Scanning is performed in a 2 × 2 pixel window indicated by 2 and the number of black pixels in the window is counted, and a portion where the count value exceeds 2 is newly set as a black pixel. By doing so, the processing result is reduced to vertical and horizontal 1/2 as shown by 2203, and a noise-removed pattern is obtained. Since the number of black pixels in the window at the position of 2202 is 1, it can be replaced with the position of 2204 as a white pixel.

Next, the center of gravity 1 of the pattern 2203 is calculated.

This can be calculated by a known method by projecting the pattern 2203 in the vertical direction and the horizontal direction.

Next, the degree of similarity is calculated by standard pattern matching. First, the standard pattern registered in advance as a dictionary in 2105 is read from the ROM 418 of FIG.
Read in PU. The standard pattern is the red stamp pattern of the current banknote, but the patterns extracted up to 2103 may be rotated depending on the angle at which the banknote is placed on the platen. Satisfactory results cannot be obtained even when compared with the standard pattern.

As the standard pattern, a plurality of patterns obtained by rotating the red stamp pattern every several degrees are created and stored in the ROM in advance, and an appropriate pattern is selected from the patterns and read into the CPU. good. As a plurality of patterns, for example, a total of 24 patterns in which a red stamp is rotated at intervals of 15 degrees from 0 degree to 360 degrees are used, and as a selection method, an angle θ of an already detected original is referred to. , −8 ≦ θ <8 degrees, the rotation angle φ
Standard pattern of degrees, rotation angle φ when 8 ≦ θ <24 degrees
If the standard pattern with a rotation angle of 180 degrees is also selected, if the standard pattern with a rotation angle of 180 degrees is also selected, it is also necessary to select the standard pattern with a rotation angle of 180 degrees.
In the case of 5 degrees and 30 degrees, 210 degrees must be selected at the same time. Therefore, various methods can be considered for calculating the degree of similarity. Figure 1
As shown in 0, the pattern extracted up to the above is defined as (a) or the standard pattern of the predetermined rotation angle selected by the above method is defined as (b), and B (i, j), P
Represented as (i, j).

(B (i, j) and P (i, j) have a value of 1 for a black pixel and φ for a white pixel).
The barycentric coordinates of B (i, j) obtained in 04 are (iB
C, jBC) and the barycentric coordinates of P (i, j) obtained in the same manner as (iPC, iPC), the similarity COR between the two
Is given by

[0091]

[Outer 1] The star represents the exclusive OR of P and B, and the formula (1) represents the Hamming distance when the centers of gravity of the patterns B (i, j) are aligned. The greater the COR, the greater the degree of similarity between the two.

In this embodiment, the equation (1) is modified (2) to improve the reliability of the similarity and suppress the occurrence of erroneous recognition as much as possible.
The degree of similarity COR is calculated using an equation.

[0093]

[Outside 2]

Where · is a logical product,

[0095]

[Outside 3] Represents the determination of P, and when both P and B are black pixels, CO
R is added by 2, and when P = 0 and B = 1, 1 is subtracted from COR, and the recognition accuracy can be greatly improved.

When the similarity COR is calculated as described above, 2
In step 107, Th and COR obtained in advance are compared.

If COR> Th, it is determined that a red stamp exists, and it is determined that a specific document exists (2108), and the collating operation ends.

When COR <Th, it means that there is no red stamp in the current processing area. When n is smaller than 4, n is incremented by 1 and 2 is added to the next area n.
The collating operations 101 to 2109 are repeated. N = 2109
In the case of 4, it means that there is no red stamp pattern in any of the first to fourth areas, and the collation operation ends with no specific document (2110).

Second Embodiment In the first embodiment, the forgery is determined by prescanning the original. However, in this method, the securities are not placed on the original table at the time of prescanning, and the image is printed. The securities can be copied by the means of replacing the securities at the time of the main scan at the time of formation.

In this example, this point was improved.

Also in this example, an infrared phosphor by multistage energy transfer was used. Specifically, BaY1.3
A phosphor compound of 4Yb0.60Er0.06F8 was used.

[Processing Flow] FIG. 15 shows the relationship between the scan mode and the printer output.

FIG. 16 shows a processing flow under CPU control. In FIG. 16, the copy start button is pressed, mode 1 is first set, 11401, and 1st scan is performed 11402. Here, the halogen lamp 205 is turned on, the infrared LED 230 is not turned on,
While moving the reading optical system in the forward direction, the document size detection, the document angle detection, and the rough position of the watermark portion in the document are detected. Therefore, CP
In the window comparator 408, U writes a value capable of detecting the background of the document in the registers 601 to 606 shown in FIG.

The output of the window comparator 408 is output to the RAM 412 at four positions which are considered to be the positions marked with red in FIG.
Written in.

Further, the pattern of red marks is read by the mode 2 set 11403 and the back direction scan 11404 of the optical system, and the pattern matching 11405 is performed by the algorithm described in the first embodiment.

The forgery determination 11406 employs the same means as in the first embodiment. If there is no possibility of forgery, that is, if the red stamp is not detected, normal image formation is performed by the scan 11408 in the forward direction. To do.

On the other hand, if it is determined in the forgery determination 11406 that there is a possibility of forgery, that is, if a red stamp is detected, forgery prevention measures are taken in 11407.

Specifically, F is set in the register 408 of FIG.
By setting FH (usually 00H is set), FFH is sent to the printer unit, toner of the color corresponding to the number of scans is attached to the entire surface, the copy is filled, and a normal copy image is obtained. Will not be obtained.

The third scanning operation, the fourth scanning operation, the fifth scanning operation, and the second scanning operation are repeated. When the fifth scanning operation is completed, 11409 and fixing output 11410 are performed to output a copy.

As described above, by performing the forgery determination 11406 a plurality of times in each scan, it becomes difficult to make a realistic forgery.

<Embodiment 3> In Embodiments 1 and 2, the system in which the infrared phosphor by multi-stage energy transfer is used for the ink is explained. In this embodiment, the red utilizing the infrared stimulating effect is used. An external phosphor was used.

As described above, the infrared stimulating effect is to generate visible light luminescence by irradiating short-wavelength light in advance and then irradiating infrared light.

Specifically, it is commercially available from Kodak. IR Phospher Plate is mentioned.

IR Phospher from Kodak
FIG. 1 shows the excitation spectrum a of the plate, the excitation spectrum b, the fluorescence spectrum c, and the emission spectrum d of the infrared LED.
7 shows.

The structure, sequence, and algorithm of the copying machine are almost the same as those in the second embodiment. Since red light is emitted as shown in the emission spectrum c in FIG. 17, the fluorescence signal is
The difference is that the red CCD is used for reading.

Here, as a supplementary note, as the excitation spectrum, the halogen lamp 205 irradiates the document with visible light in advance during forward scanning, so that sufficient excitation light is provided during each scan, and the excitation light is stimulated. As a result, when the infrared LED 230 irradiates, there is a secondary effect that light emission is stably formed.

As described above, when the specific original is irradiated with the excitation light of the specific wavelength, the specific pattern is printed in advance using the ink having the characteristic of emitting light on the shorter wavelength side than the specific wavelength, and the excitation is performed. The specific pattern is read by the sensor means having the wavelength characteristic of the predetermined band including the wavelength of light and having the sensitivity in the wavelength band shorter than the predetermined band including the emission wavelength, and is registered in advance. By determining the degree of similarity with the specific pattern, it is possible to detect the copy-inhibited document without affecting the actual use state with visible light.

Further, by providing a light source having an excitation spectrum component and providing a filter for attenuating the fluorescence wavelength component in front of the light receiving element, it becomes possible to read fluorescence information with a good S / N.

Further, since the emission spectrum component is in the visible light region, the commonly used visible light receiving CCD can also be used.

Further, by recording information that cannot be identified by visible light as visible information, it is possible to prevent the normal copy operation of the copy-inhibited document.

When a light having a specific wavelength is applied, the specific pattern can be read from an original printed with the specific pattern using ink that emits another wavelength at a timing different from the image forming sequence. As a result, it becomes possible to detect the copy-inhibited document without affecting the actual use state under visible light.

[0122]

As described above, according to the present invention, it is possible to reliably identify a specific original.

[Brief description of drawings]

FIG. 1 is a diagram showing a detected state of an identification mark of a copy-prohibited document in the first to third embodiments.

FIG. 2 is a configuration diagram of a color copying apparatus using the present invention.

FIG. 3 is a configuration diagram of a signal processing unit according to the first embodiment.

FIG. 4 is a block diagram of the window comparator shown in FIG.

FIG. 5 is a block diagram of noise removal of fluorescence signals in the first to third embodiments.

FIG. 6 is a block diagram for detecting the positions of fluorescent marks in the first to third embodiments.

FIG. 7 is an address generation unit for a memory that stores fluorescent marks in the first to third embodiments.

FIG. 8 is a principle diagram of position detection in the first to third embodiments.

FIG. 9 is an operation flowchart of pattern matching of the CPU in the first to third embodiments.

FIG. 10 is a schematic diagram of pattern matching of fluorescent mer in the first to third embodiments.

FIG. 11 is a configuration diagram of a CCD sensor according to the first to third embodiments.

FIG. 12 is an excitation spectrum of infrared phosphors and spectral characteristics of infrared LEDs in the first and second embodiments.

FIG. 13 is an emission spectrum diagram of the infrared phosphors in the first and second examples.

FIG. 14 is a flowchart of the first embodiment.

FIG. 15 is a diagram showing the relationship between scans and modes in the second and third embodiments.

FIG. 16 is a flowchart of the second and third embodiments.

FIG. 17 is an excitation spectrum, a photostimulation spectrum, an emission spectrum of an infrared phosphor, and a spectral characteristic diagram of an infrared LED in a third example.

FIG. 18 is a diagram illustrating the spectral characteristics of CCD.

FIG. 19 is a diagram illustrating an infrared lot filter.

[Explanation of symbols]

 210-1 to 210-3 CCD 408 Wind comparator 412 RAM 417 CPU

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location G03G 21/00 (72) Inventor Toshio Hayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. Company (72) Inventor Tetsuya Nagase 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Shinobu Arimoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. ( 72) Inventor Takehiko Nakai, 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (3)

[Claims] 1. An illumination unit for irradiating an original including excitation light of a specific wavelength, and a unit for detecting light having a wavelength shorter than the specific wavelength among reflected light from the original. A characteristic image processing device. 2. The detection means is a substance on a document,
The image processing apparatus according to claim 1, wherein when a specific document is irradiated with excitation light of a specific wavelength, a document having a characteristic of emitting light on a shorter wavelength side than the specific wavelength is detected. 3. The image processing apparatus, further comprising a discriminating unit for discriminating whether or not the original is a specific original according to the detection result of the detecting unit.