JP3155841B2 - Image processing device - Google Patents

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 reading a plurality of pieces of information whose wavelength characteristics are visible and non-visible.

[0002]

2. Description of the Related Art Conventionally, there has been known a technique of reading data of color components having different wavelength characteristics using, for example, R, G, and B line sensors.

[0003]

However, conventionally, it has not been sufficiently considered that visible information and non-visible information are read by the same device and used for image processing. For example, when invisible information and visible information are read, visible information and visible information are not read. In a sensor that reads information, information to be read is read by a sensor that reads invisible information, which may cause a problem such as an adverse effect.

Accordingly, an object of the present invention is to provide an image processing apparatus capable of efficiently reading an original in which a plurality of pieces of information whose wavelength characteristics are visible and other than visible are mixed.

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, an image processing apparatus according to the present invention obtains a first plurality of line sensors corresponding to a plurality of different colors for obtaining visible information, and obtains invisible information. And a distance L1 between the first plurality of line sensors.
The second line sensor is arranged at a position separated by a distance L2 larger than the first line sensor, and the first plurality of line sensors and the second line sensor are monolithically configured. Further, the invisible information is infrared information. Furthermore, the invisible information is information based on fluorescence.

[0006] The present invention is characterized in that it has a first sensor for cutting invisible information of a document and reading color visible information, and a second sensor for reading excitation information based on fluorescence of the document.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS <First Embodiment> The present invention will be described below based on a preferred embodiment.

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

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

In FIG. 1, reference numeral 201 denotes an image scanner, which reads a document and performs digital signal processing. Reference numeral 202 denotes a printer unit, which outputs a full-color image corresponding to the document image read by the image scanner 201 to a sheet of paper.

In the image scanner section 201, 20
Numeral 0 is a mirror surface thick plate, and a platen glass (hereinafter, platen) 2
The document 204 on the document 03 is irradiated with light from a halogen lamp 205 that has passed through an infrared cut filter 208 for removing infrared rays. Reference numeral 227 denotes a reflector for irradiating the original with the light of the halogen lamp 205 effectively. The reflected light from the original is guided to mirrors 206 and 207 and forms an image on a four-line CCD sensor (hereinafter referred to as a CCD) 210 by a lens 209. Each line sensor performs full-color information red (R) based on visible light. A green (G) and blue (B) component and an infrared information (IR) component based on light in a wavelength region other than visible are generated and sent to the signal processing unit 211. Note that 205 and 206 are speeds v,
Reference numeral 207 denotes 1/2 V, which scans the entire surface of the document by mechanically moving in a direction perpendicular to the electrical scanning direction (hereinafter, main scanning direction) of the line sensor (hereinafter, main scanning direction).

Reference numeral 5102 denotes a standard white plate;
210-4 are used to generate correction data (shading data) for correcting variations in the read data of the IR, R, G, and B line sensors for each pixel. This standard white plate has a substantially white color with respect to visible light as shown in FIG. 31 (curve 2070).
1), and excitation light having a characteristic such as a curve 20702 (FIG. 31) that is substantially transparent to visible light and has a fluorescence characteristic substantially equivalent to the fluorescence information to be detected shown in FIG. , A fluorescent ink that generates fluorescence having a characteristic as indicated by a curve 20703 (FIG. 31) is uniformly applied. The output data of the IR line sensor 210-1 with respect to infrared light is corrected, and It is used for shading correction of output data of the visible light line sensor 210-4.

In the signal processing unit 211, the sensors 210-1 to 210-1
Electrically processing the signal read by 210-4,
The image is decomposed into components of magenta (M), cyan (C), yellow (Y), and black (Bk), and sent to the printer unit 202. In addition, for one original scan (scan) in the image scanner unit 201, one component among M, C, Y, and Bk is sent to the printer 202, and one print is completed by a total of four original scans. I do.

The M, C, Y, and Bk plane-sequential image signals sent from the image scanner unit 201 are sent to a laser driver 212. The laser driver 212 modulates and drives the semiconductor laser 213 according to the image signal of each color.
The laser light is reflected by the polygon mirror 214 and the f-θ lens 21.
5. Scan the photosensitive drum 217 via 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. A black developing device 222 is provided. The four developing devices alternately contact the photosensitive drum, and develop the M, C, Y, and Bk electrostatic latent images formed on the photosensitive drum 217 with the corresponding toner.

Reference numeral 223 denotes a transfer drum.
4 or 225 to the transfer drum 2
23, and transfers the toner image developed on the photosensitive drum 217 to a sheet.

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

FIG. 13 shows a halogen lamp 205 for document illumination.
4 shows the spectral characteristics of an infrared cut filter 208 disposed between the infrared cut filter 208 and the platen glass 203. As a result, of the spectral characteristics of the halogen lamp 205 shown in FIG.
The above infrared light is cut.

The halogen lamp 205 is commonly used for reading visible information and infrared fluorescent information other than visible information, and has both the illumination wavelength components necessary for reading the above two types of information. The reflector 227 is also provided in common for reading the above two types of information. By making the illumination system common in this way, each of the reflectors 227 does not have a plurality of independent illumination systems for reading respective information, It is possible to effectively irradiate the document with illumination light of different wavelength components for reading information.

FIG. 15 shows the configuration of the CCD 210 used in this embodiment.

In FIG. 15A, reference numeral 210-1 denotes a light receiving element array (CCD line sensor) for reading infrared light (IR) having a wavelength characteristic other than visible light.
2, 210-3 and 210-4 are light receiving element arrays (CCD line sensors) for reading the R, G, and B wavelength components in order.

The four light receiving element rows having different optical characteristics are arranged so that the IR, R, G, and B line sensors are arranged in parallel to each other to read the same line of the original.
They are monolithically configured on the same silicon chip.

By using the CCD line sensor having such a configuration, an optical system such as a lens can be shared for reading visible light and reading infrared light, and the configuration can be simplified. It is.

Further, the accuracy of optical adjustment and the like can be improved, and the adjustment can be facilitated.

FIG. 15B is an enlarged view of the light receiving element array. Each sensor has a length of 10 μm per pixel in the main scanning direction. Each sensor is in the short direction (297m
m) has 5000 pixels in the main scanning direction so that it can be read at a resolution of 400 dpi.

The distance between the lines of the R, G, and B sensors is 80 μm, and each line is separated by 8 lines for a sub-scanning resolution of 400 lpi.

IR sensor 210-1 and R sensor 210-
The line spacing of 2 is 160 μm (1
6 lines).

R, G, B from 210-2 to 210-4
Each of the sensors has an aperture of 10 μm in the sub-scanning direction.
The aperture of the IR sensor 10-1 is twice as large as that of the IR sensor. This is because the IR sensor 210-1 reads infrared fluorescent light. That is, generally, the intensity of the fluorescent light is less than half of the excitation light, and may be about 10% or less. Therefore, in this embodiment, the dynamic range of the infrared reading signal is secured by increasing the light receiving area per pixel at the expense of the sub-scanning reading resolution of the IR sensor.

In this embodiment, the dynamic range of the signal is ensured by increasing the length of the sub-scanning pixels of the IR sensor. However, the pixel length in the main scanning direction is increased by lowering the resolution in the main scanning direction instead of the sub-scanning direction. May be.

Each line sensor has an optical filter formed on the sensor surface in order to obtain predetermined spectral characteristics of IR, R, G and B.

The spectral characteristics of the R, G, and B line sensors of the CCD 210 will be described with reference to FIGS.

FIG. 19 shows the conventional R, G,
B shows the characteristics of the filter. As can be seen from this figure, the conventional R, G, B filters have sensitivity to infrared light of 700 nm or more. Conventionally, the lens 209 is provided with the infrared cut filter shown in FIG. In this embodiment, the infrared component of the light passing through the lens
-1 need to be read by IR sensor,
09 cannot have the function of an infrared cut filter.

Therefore, in order to eliminate the influence of the infrared light, a filter attached to each of the R, G, and B sensors should have both the characteristic of each color shown in FIG. 19 and the characteristic of the infrared cut shown in FIG. Used.

FIG. 16 shows the characteristics of the visible cut filter attached to the IR sensor 210-1. This filter is for removing a visible light component incident on an IR sensor that reads an infrared fluorescent component.

FIG. 17 shows the structure of a photodiode of a CCD. This photodiode has an npn structure, and the upper np junction is reverse-biased to form a photodiode. Carrier 251 generated on top of p-layer
Is absorbed by the upper np junction and taken out as a signal.

Light having a long wavelength, such as infrared light, generates carriers 252 in the deep part of the p-layer and generates carriers 253 in the n-layer of the substrate. The carriers generated in the deep portion are absorbed by the pn junction as shown in the figure, and are not read as a signal.

A characteristic 261 indicated by a solid line in FIG. 18 indicates a spectral characteristic of a general visible CCD. 800 at peak 550 nm
Infrared light of nm causes a reduction in sensitivity of about 20%.
The thickness of the p-layer of the R, G, B sensor exhibiting the characteristics of 261 is about 1000 nm.

In this embodiment, 210-1 for IR reading is used.
In this CCD, the thickness of the p-layer is made thicker than other CCDs on the same silicon chip in order to make infrared light sensitive. That is, the thickness of the p-layer of the IR sensor is from 700 nm to 8
The thickness is about 1500 nm so as to have a peak in sensitivity to infrared light having a wavelength of 00 nm. I in the present embodiment
The spectral characteristics of the R sensor are shown at 262 in FIG.

In FIG. 15, the interval between the IR sensor 210-1 and the R sensor 210-2 is set to be twice the interval between the other sensors because the p-layer of the IR sensor 210-1 is thick.
This is because it is necessary to reliably perform the structural separation between the photodiode and the serial charge transfer sections formed on both sides of the photodiode. Further, sensors having different structures such as the thickness of the light receiving layer are formed outside the other sensors to simplify the structure of the CCD.

By increasing the line interval,
The distance between the charge transfer section for the IR signal and the charge transfer section for the R signal is set wider than the distance between the charge transfer sections between the other RGs and GBs. As a result, the influence of the cross stroke exerted on the fluorescent signal which is a minute signal by the R signal having a relatively large signal level read at the same time is reduced.

Further, by arranging the IR sensor on the outermost side of the four-line sensor, the cross stroke from other signals is reduced.

Hereinafter, in this embodiment, as an example of a copy-inhibited document that should not be copied, a mark similar to a red seal is printed at a predetermined position on the document as shown in FIG. It is assumed that the manuscript has been set. When the mark is detected in the infrared signal read from the document placed on the document table, the normal image forming operation is blocked. As a blocking method, various methods such as changing the image data and turning off the power of the apparatus itself can be considered as described later.

The size and mark of the copy-inhibited document are not limited to those shown in FIG.

FIG. 24 shows the reflection spectral characteristics of a copy-inhibited document recognition mark (hereinafter, a recognition mark) included in the copy-inhibited document targeted in this embodiment.

In FIG. 12, reference numeral 12201 denotes a spectral characteristic obtained by synthesizing the infrared cut filter 208 disposed between the halogen lamp 205 and the platen glass 203. Of this spectral characteristic, in the present embodiment, infrared light component 12202 near about 700 nm is used as excitation light, and copying is prohibited by detecting infrared fluorescence having a peak at about 800 nm from the recognition mark 12203 in the drawing. The original is identified. In this embodiment, a halogen lamp is used as a document illumination lamp that simultaneously generates at least excitation light components for visible light and infrared fluorescent light. The wavelength component of the reflected light does not reach the document surface from the halogen lamp.

In this embodiment, the recognition mark is formed by using a material which is excited by infrared light and generates fluorescence by infrared light. Therefore, the characteristics of this recognition mark with respect to visible light can be set arbitrarily. In this embodiment, by using infrared fluorescent ink that exhibits a characteristic that is substantially transparent to visible light, infrared fluorescent ink can be used without making a general apparatus user aware of the presence of a recognition mark in a copy-protected document. By detecting, it is possible to determine that the original is a specific original whose copying is prohibited.

Hereinafter, the principle of reading IR fluorescence will be briefly described. The document 204 on the platen glass 203 is irradiated with light from a halogen lamp 205 passing through an infrared cut filter 208. As described above, generally, the intensity of the fluorescence of, for example, 800 nm emitted from the recognition mark is as weak as less than half of the excitation light, for example, on the order of 10%. Therefore, the long-wavelength component including the wavelength component of the 800 nm infrared fluorescent light, which is directly reflected from the document, is cut by the infrared cut filter 208 and the 800
The wavelength component of nm is substantially a fluorescent component.
In this way, the light emitted from the light source to the document cuts the spectral component of the fluorescence emitted from the recognition mark, and the 700 nm fluorescence excitation light sufficiently irradiates the document to reduce the fluorescence from the recognition mark. The S / N ratio of the signal is improved.

The light reflected from the original is reflected by mirrors 206 and 207.
Through the lens 209, an image is formed on each line sensor for reading the full-color information red (R), green (G), and blue (B) components on each sensor of the CCD 210 and the infrared information (IR) component.

As described above, the R, G, and B line sensors 210-2 to 210-4 have R, G, and B having the characteristics of FIG. 20 that sufficiently attenuate the 700 nm excitation light.
Since the filter B is attached, full-color reading can be performed without being affected by the infrared fluorescence excitation wavelength of 700 nm and the infrared fluorescent light.

Also, since the IR sensor 210-1 is provided with a filter for cutting 700 nm or less as shown in FIG. 16, only the infrared fluorescent component 12203 shown in FIG. 24 is read. With these filters, infrared fluorescence can be extracted at the same time as the document reading and image recording operations, and an extra document scanning operation only for detecting a recognition mark by infrared fluorescence such as a prescan is not required.

With the above configuration, the normal color area of the document and the infrared area of the recognition mark are well separated.

FIG. 4 is a block diagram showing the flow of an image signal in the image scanner unit 201. An image signal output from the CCD 210 is output to an analog signal processing unit 4001.
8 bit in the analog signal processing unit 4001
After being converted into a digital image signal, the image signal is input to the shading correction unit 4002. A decoder 4008 decodes the main scanning address from the main scanning address counter 419 and generates a line-by-line CCD drive signal such as a shift pulse or a reset pulse.

FIG. 21 is a block diagram of the analog signal processing section 4001. Here, since the processing circuits for IR, R, G, and B are all the same, only one of them is shown. The image signal output from the CCD 210 is sampled and held by a sample and hold unit (S / H unit) 4101 to stabilize the waveform of the analog signal. CP
U417 controls the variable amplifier 4103 and the clamp circuit 4102 via the voltage control circuit 4103 so that the image signal can fully utilize the dynamic range of the A / D converter 4105. The A / D converter 4105 converts the analog image signal into an 8-bit digital image signal.

The 8-bit digital image signal is subjected to shading correction in a shading correction unit 4002 by a known shading correction method.

In response to the read signal from the IR sensor 210-1, the CPU stores the read infrared fluorescent signal for one line from the standard white plate 5102 in the line memory 4003, and stores each pixel recorded in the line memory. A multiplication coefficient for making the read data of 255 into a level of 255 is obtained for each pixel, and this is stored in the coefficient memory 4006 for one line. Then, at the time of actual document reading, the IR sensor 210
The multiplication coefficient corresponding to the pixel is read out from the coefficient memory in synchronization with the output of each pixel by the line reading of −1, and is applied to each pixel signal from 210-1 by the multiplier 4007, thereby shading the infrared fluorescent light. Make corrections.

In the shading correction for the R, G, and B signals, similarly to the case of the IR signal, a read signal for one line from the standard white plate 5102 is written to a line memory, and a multiplication coefficient for setting the value to 255 is used. The coefficient is stored in a coefficient memory, and the multiplier multiplies the read signal by a multiplication coefficient for each pixel from the coefficient memory.

As shown in FIG. 15, since the light receiving sections 210-1, 210-2, 210-3, 210-4 of the CCD 210 are arranged at a predetermined distance, the line delay elements 401, 402, 4005 In, the spatial shift in the sub-scanning direction is corrected. Specifically, the IR, R, and G signals for reading the original information in the sub-scanning direction with respect to the B signal are delayed in the sub-scanning direction to match the B signal. 403, 40
4, 405 are log converters, and look-up tables R
OM, and the R, G, B luminance signals are C, M,
It is converted into a Y density signal. Reference numeral 406 denotes a known masking and UCR circuit, which will not be described in detail. However, Y, M, C, and B for output are output according to the input three primary color signals.
A signal of k is sequentially output at a predetermined bit length, for example, 8 bits, for each reading operation.

FIG. 23 is a block diagram of a light quantity control unit of the halogen lamp 205, and 4301 is a light quantity control unit of the halogen lamp.

Next, using the flowchart of FIG.
Method for adjusting light quantity of halogen lamp 205 and variable amplifier 4
103, a control method of the clamp circuit 4102 will be described.

In the analog signal processing unit 4001, the A / D
In order to fully utilize the dynamic range of the converter 4105, a standard white plate 5102 is used for R, G, and B signals.
Variable amplifier 4 based on the image data when
The gain of the clamp circuit 4102 is adjusted based on the image data in a state where the CCD 210 is not irradiated with light.
Are adjusted by the voltage control circuit 4103. In the case of an IR signal, adjustment is performed in the same manner as in the case of R, G, and B based on image data obtained by reading infrared fluorescent information from the standard white plate 5102.

When the adjustment mode is started from an operation unit (not shown), the reflection mirror 206 is moved below the standard white plate 5102 to set a specified gain for the halogen lamp in the variable amplifier 4103 (step 1). CCD210
Image data in a state where light is not irradiated to the line memory (shading RAM) 4003, and the obtained image data is calculated by the CPU 417. Voltage control is performed so that the average value of the image data for one line is closest to 08H. The circuit 4103 is controlled, and the clamp circuit 4 is controlled.
The reference voltage of 102 is adjusted (steps 2 and 3), and the adjusted control value is stored in RAM 418 attached to CPU 417 (step 4).

Next, the halogen lamp 205 is turned on, the image data obtained when the standard white plate 5102 is read is fetched into the line memory 4003, and the peak value of the G signal becomes D0.
H to F0H so that the light amount control unit 4301
Is controlled by the CPU 417 (steps 5 and 6 for adjusting the halogen lamp), and the adjusted control value is stored in the RAM 418 attached to the CPU 417 (step 7). Next, the halogen lamp 205 is turned on with the light amount adjusted in steps 5 and 6, and the image data obtained when the standard white plate 5102 is read is stored in the line memory 40 corresponding to each of the R, G, and B colors.
03, and controls the voltage control circuit 4103 so that the peak value of the image data becomes a value between E0H to F8H for each of R, G, and B colors, and sets the gain of the variable amplifier 4103 to R, G, B. Adjust for each color (Step 8,
9) The data is stored in the RAM 418 attached to the CPU 417 as gain data (hereinafter, H-gain data) when the halogen lamp 205 is used (step 10).

Next, the adjustment operation of the clamp circuit and the variable amplifier of the analog signal processing unit that handles the read signal from the IR sensor and the operation of storing the control value will be described. To read the standard white plate, the halogen lamp 205 is turned off, and the reflection mirror 206 is moved below the standard white plate 5102 (step 11). The image data in a state where light does not hit the CCD 210 is taken into a line memory for IR signals, and the taken image data is calculated by the CPU 417 so that the average value of the image data for one line is closest to 08H. The voltage control circuit 4103 is controlled to adjust the reference voltage of the clamp circuit 4102 (steps 12 and 13), and the adjusted control value is stored in the RAM 418 attached to the CPU 417 (step 14). Next, the halogen lamp 205 is turned on with the light amount adjusted in Steps 5 and 6, and the infrared fluorescent image data obtained when the standard white plate 5102 is read is fetched into the line memory for IR. Peak value of E
The voltage control circuit 4103 for the IR signal is controlled so as to have a value between 0H and F8H, and the variable amplifier 410
3 is adjusted for each of R, G, and B colors (step 1).
5, 16), CPU gain data for IR signals
417 is stored in the RAM 418 attached thereto, and the halogen lamp is turned off (step 17).

The control data obtained in the above adjustment mode is set in each control unit when the power is turned on.

The normal copy operation and the accompanying fluorescent mark determination operation will be described below.

When the operator places a document on the platen 203 and starts a copy operation from an operation unit (not shown), the CPU 417 controls a motor (not shown) to move the reflection mirror 206 below the standard white plate 5102.

Next, the halogen lamp 5101 is turned on,
The standard white plate 5102 is irradiated, and the shading correction unit 4
In 002, shading correction for R, G, B signals is performed.

Next, the CPU turns on the halogen lamp 5101, irradiates the standard white plate 5102, and performs shading correction for an IR signal using infrared fluorescent light in the shading correction unit 4002.

Next, the original is read four times in accordance with the image recording operation of the four colors M, C, Y, and Bk in the printer unit, and image recording is performed. And the recording operation is controlled in accordance with the detection result.

In this embodiment, copying is performed in a total of four reading operations (scans) as described above.
1 and the operation of the printer 202 are shown in FIG.

That is, when forgery of a copy-inhibited document is to be prevented, at the time of the first scan, the image scanner detects the approximate position of the fluorescent mark in the mode 1 and the printer unit outputs magenta. I do.

At the time of the second scan, the image scanner is in the mode 2 mode, extracts the fluorescent mark from the position of the fluorescent mark detected in the first scan, stores it in the memory, and inhibits the predetermined copy. It is determined whether or not the mark. The printer outputs cyan.

At the time of the third and fourth scans,
If the image scanner is in mode 3 and it is determined that counterfeiting was attempted during the second scan,
Take specific measures to prevent counterfeiting.

FIG. 5 is an operation timing chart of each section in the image scanner section of this embodiment.

The VSYNC signal is an image effective section signal in the sub-scanning direction. In the section of "1", image reading (scanning) is sequentially performed (C), (M), (Y), (B).
k) forming the output signal. VE is an image valid section signal in the main scanning direction, and the timing of the main scanning start position is set in the section of “1”. The CLK signal is a pixel synchronization signal, and transfers image data at the rising timing of 0 → 1. CLK8 is a timing signal for every eight pixels,
At the rising timing of 0 → 1, the timing of an 8 × 8 block-processed signal described later is set.

(Image Scanner Unit) The detection of a fluorescent mark in an internal block of the image scanner 201 of FIG. 4 and the generation of a printer recorded image will be described below. 40
Reference numerals 3, 404, and 405 denote log converters, each of which is constituted by a look-up table ROM, and converts R, G, and B luminance signals into C, M, and Y density signals, respectively. Reference numeral 406 denotes a well-known masking and UCR circuit, which will not be described in detail.
The M, C, and Bk signals are sequentially output at a predetermined bit length, for example, 8 bits for each reading operation. 407 is OR
This is a gate circuit, which takes a logical OR with the value held in the register 408. Register 408 normally contains 00
_H is written and the output of 406 is output to the printer unit as it is.
417 sends FF _H to the register 408 via the data bus.
By setting, an image filled with yellow or black toner can be output.

A CPU 417 controls the apparatus in each mode. Reference numeral 4009 denotes a binarization circuit, which binarizes the infrared fluorescent signal at an appropriate slice level. In the output of the binarization circuit, "1" indicates the presence of a fluorescent mark, and output "0" indicates that no fluorescent mark exists for each pixel.

The block processing circuit 409 performs 8 × 8 block processing, and processes the output of the binarization circuit 409 for each 8 × 8 block.

Reference numeral 412 denotes a readable / writable random access memory (RAM). The selector 411 switches the data and the selector 413 switches the address.

On the other hand, reference numeral 419 denotes a main scanning counter.
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 denotes a sub-scanning address counter.
HSNC is reset in the period of "0" of VSYNC signal.
It counts up at the timing of the Y signal to generate 13-bit sub-scanning addresses (Y addresses) Y12 to Y0.

The CPU 417 selects the selectors 411, 413, 415, 416 and the address decoder 4 according to each mode.
14 to read and write data from and to the RAM 412. 418 is an R added to the CPU 417.
AM / ROM. Reference numeral 410 denotes a fluorescent mark detection circuit that detects the position of the fluorescent mark.

FIG. 6 is a block processing circuit 409 shown in FIG.
It is a figure which shows the internal detail of.

701, 702, 703,..., 706, 7
Reference numeral 07 denotes seven D flip-flops (hereinafter, DFFs) arranged in series, which sequentially delay the input signal with the pixel clock CLK signal. VE = "0"
Cleared to "0" in the non-image section.

738 is a 4-bit up / down counter, 737 is an EX-OR gate, 740 is an AND gate, and the operation is based on the following table.

[0086]

[Table 1]

That is, the output of the counter 738 is VSY
When NC or VE is “0”, it is cleared to 0, and X _t
= _Xt- 7, _Xt = 1 and _Xt-7 =
When it is 0, it is counted up, _Xt = 0 and _Xt-7
When = 1, the countdown is performed. And it outputs the sum of input data _{X t} of 8 graphics entered by latching by the latch 739 to the counter output of the 8 clock periods in CLK8 to one period of the CLK8 (= number of 1).

Further, the output is a line-by-line FIF.
O memory 721, 722, 723, ..., 726, 727
Thus, data for eight lines are simultaneously input to the adder 741, and the sum thereof is output. As a result, the sum SUM of the number 1 in the 8.times.8 window is output as 0 to 64.

A digital comparator 742 compares the output SUM of the adder 741 with a 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 can be removed in units of 8 × 8 blocks.

FIG. 7 is a diagram for explaining the fluorescent mark detection circuit 410.

Reference numeral 827 denotes a line thinning circuit, which outputs one VE signal to eight lines. Since the writing control of each FIFO memory is performed by the VE signal thinned to 1/8, the content of each FIFO memory is updated every eight lines. Since each F / F operates at CLK8, the operation of this circuit is performed in units of 8 pixels / 8 lines.

828, 829, and 830 are three FIFOs.
, Giving a delay of one line each, and processing four lines simultaneously.

831,832,833, ..., 839,8
40 and 841 are 3 for output for 4 lines, respectively.
Are DFFs arranged in series, and all DFFs are CFFs.
Driven by LK8. By OR gate 857, 4
If there is at least one (there is a fluorescent mark) in the x4 area, all of the 4x4 areas (2 mm x 2 mm on the original) are set to 1. As a result, all of the gaps between the marks are filled as fluorescent mark portions.

842, 843 and 844 are three FIFOs
, Giving a delay of one line each, and processing four lines simultaneously.

845, 846, 847,..., 854, 8
55 and 856 are 3 lines for output of 4 lines, respectively.
Are DFFs arranged in series, and all DFFs are CFFs.
Driven by LK8. By AND gate 858,
All 4 × 4 areas output 1 (there is a fluorescent mark). As a result, when the gap portion between the marks is filled, the portion outside the mark that swells as the fluorescent mark portion is returned to the original size. As a result, it is possible to prevent the noise component of the fluorescence signal from expanding due to the contamination of the document.

821, 820,..., 821 are 18 F
IFOs, each providing one line delay, and 19 lines are processed simultaneously.

801, 802, 803,..., 804, 8
05,806,807, ..., 808, ..., 809,81
0, 811, ..., 812, ..., 813, 814, 81
, 816 are DFFs arranged in series for 10 outputs for 19 lines, respectively.
Reference numeral 18 denotes DFFs further arranged in a series of nine after the DFF 812, and all DFFs are driven by CLK8. Via AND gates 823, 824, 825,
DFFs 804, 808, ..., 812, 816 (19
Block) and DFFs 809, 810, 811, 81
When the outputs of 2,817,818 (19 horizontal blocks) are all "1", 1 is output.

One block is 8 pixels / 8 lines, which corresponds to about 0.5 mm square on a document. That is, when the fluorescent marks are continuous for 9.5 mm in each of the vertical and horizontal directions, the approximate center position of the mark at that time is latched by the latch 826 as Position data and sent to the CPU.
By setting the size of 9.5 mm to an eye slightly smaller than the size of the mark in the copy-inhibited document, the position of the mark can be reliably detected while eliminating the influence of the noise component.

FIG. 8 is a block diagram of the address decoder 414.

Reference numerals 901, 902, and 909 are registers directly connected to the data bus of the CPU, and a desired value is written by the CPU.

Reference numerals 914 and 915 denote subtracters, which input A,
AB is output for B, and the MSB of the output is a sign bit, and when it becomes negative, it is output as MSB = 1. 916 and 917 are comparators, and inputs A and B
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 AND
When the value BXY is written to the register 909 as a result, Xou = X address−RX1 You = Y as long as RX1 <X address <RX1 + BXY and RY1 <Y address <RY1 + BXY (1) hold. Address-RY1 Enab = 1 is output. That is, RX for main scanning and sub-scanning
An area of BXY size is addressed with 1, RY1 as the start address.

<Processing Flow> FIG. 3 shows four scans from the first scan to the fourth scan in the present apparatus, three modes from mode 1 to mode 3 in the image scanner, and the printer unit. Indicates output contents.

FIG. 9 shows a processing flow under CPU control. In FIG. 9, a mode 1 for the first scan is set in the CPU at 1001.

In this state, at 1002, the first scan is started. In mode 1, the printer outputs magenta and detects the approximate center position of the fluorescent mark portion in the copy-inhibited document.

FIG. 1 shows a copy-inhibited manuscript equivalent to a 10,000-yen bill placed on the manuscript table. In the first scan, that is, in mode 1, the central part of the hatched fluorescent mark portion, that is, FIG. At a portion corresponding to (Xc, Yc), an address corresponding to (Xc, Yc) is latched by the latch 826 and sent to the CPU.

The CPU is at the center of the fluorescent mark (Xc,
The value of Yc) can be roughly known.

Next, in step 1006, mode 2 for the second scan is set. That is, the selector 411 is set to B, the selector 413 is set to A, and the selectors 415 and 416 are set to B.

In the address decoder 414, the position of the fluorescent mark is set so that RX ₁ = X _S1 RY ₁ = Y _S1 (1 pixel unit). Where X
_As described in the description of the mark detection circuit in FIG. 7, _C and YC are data of the center position of the mark in the detection range of 9.5 mm. In order to sufficiently cover the range of the fluorescent mark having a diameter of 10 mm to 20 mm, the number of pixels (472 at 400 dpi) corresponding to about 30 mm is set in BXY.

The head addresses XS1 and XY1 are each 15 mm (236 dpi at 400 dpi) from Xc and Yc.
A value from the origin is set for the pixel).

Next, in 1007, the second scan is performed, and the second scan from the dotted area including the fluorescent mark in FIG. 1 is performed.
The quantified fluorescence signal is written to the RAM 412.

Further, in 1008, it is detected whether or not the mark is a fluorescent mark by an algorithm described later. 100
If there is no possibility of forgery, that is, if no fluorescent mark is detected, 3rd scan and 4th scan are performed in 1010, and four colors of Y, M, C, and Bk are performed in a normal operation. Developed with 1 toner
The output is fixed at 012.

On the other hand, if it is determined in step 1009 that there is a possibility of forgery, that is, if a fluorescent mark is detected, counterfeit prevention measures are taken in step 1011.
Specifically, FFH is stored in the register 408 in FIG.
Is set (usually 00H is set), FFH is sent to the printer section, and the Y and Bk toners adhere to the entire surface, making copying impossible.

<Pattern Matching> Next, pattern matching of the fluorescent mark 1008 will be described in detail. When a fluorescent mark is attached to a bill or the like, the mark may be different between the front and the back. Therefore, in order to distinguish one type of copy-inhibited document, two fluorescent mark patterns are used when performing pattern matching. It is registered in advance.

When the specific portion of the specific document is written into the RAM 412, the CPU 417 refers to the contents of the RAM 412 and performs a pattern collating operation. FIG. 10 shows a flowchart of the pattern matching. The RAM 412 stores binarized data of a specific portion.

The processing after step 2102 is performed on this area. In 2102, window processing for noise removal is performed.

Assume that the binary image in area 1 is 2201 in FIG. Here, it is assumed that a small square represents one pixel, a white pixel is a white pixel, and a hatched portion is a black pixel. This is scanned in a 2 × 2 pixel window indicated by 2202, the number of black pixels in the window is counted, and a portion where the count value exceeds 2 is newly defined as a black pixel. By doing so, the processing result is reduced to half in the vertical and horizontal directions as indicated by 2203, and a pattern from which noise has been removed is obtained. Since the number of black pixels in the window at the position of 2202 is 1, it is replaced by 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 well-known method by projecting the pattern 2203 in the vertical and horizontal directions.

Next, the similarity is calculated by standard pattern matching. First, in step 2105, a standard pattern registered in advance as a dictionary is stored in the ROM 418 of FIG.
Read in PU. The standard pattern is the fluorescent pattern of the copy-inhibited document that is currently targeted.
There is a possibility that the pattern extracted up to 03 may be rotated depending on the angle at which the document is placed on the platen. Even if this is compared with a single standard pattern, a satisfactory result cannot be obtained.

FIG. 12 shows this state. Therefore, as the standard pattern, a plurality of patterns obtained by rotating the fluorescent pattern every several degrees may be created and stored in the ROM in advance, and an appropriate pattern may be selected from these and read into the CPU. As the plurality of patterns, for example, a total of 24 patterns in which the mark is rotated every 15 degrees from 0 to 360 degrees are used. Accordingly, various methods can be considered for calculating the similarity. For example, the following method can be considered. As shown in FIG. 12, the pattern extracted up to the above is defined as (a) or a standard pattern having a predetermined rotation angle selected from the patterns rotated by 15 degrees by the above method is defined as (b), and B (i, j), P (i,
j). (B (i, j) and P (i, j) take a value of 1 for a black pixel and a value of 0 for a white pixel.)
The coordinates of the center of gravity of B (i, j) obtained in
_BC , j _BC ), and assuming that the barycentric coordinates of P (i, j) obtained in the same manner are (i _PC , j _PC ), the similarity CO
R is given by the following equation.

[0123]

[Outside 1] Represents the exclusive OR of P and B, and expression (1) is the pattern B
It represents the Hamming distance when the center of gravity of (i, j) is aligned. The greater the COR, the greater the similarity between the two.

In this embodiment, the expression (1) is modified (2) in order to improve the reliability of the similarity and minimize the occurrence of erroneous recognition.
The similarity COR is obtained using the equation.

[0125]

[Outside 2] Where · is the logical product,

[0126]

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

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

If COR> Th, it is determined that a fluorescent mark exists, and there is a copy-inhibited document (210).
The matching operation ends as 8).

If COR <Th, it is determined that there is no fluorescent mark in the current processing area, and the collation operation ends with no copy-inhibited document (2110).

<Second Embodiment> This embodiment is intended to detect the existence of fluorescent light, not the form of infrared fluorescent information in a copy-inhibited document.

As copy-inhibited manuscripts such as banknotes, there are also ones such as Canadian dollars in which a fiber of paper of a banknote is mixed with fluorescent material. In this embodiment, a copy-inhibited document is detected by detecting infrared fluorescent light from such fine line information of a fiber or the like.

FIG. 25 shows a control block in this embodiment. Here, instead of performing the pattern matching of the fluorescent mark, the number of pixels of the fluorescent information included in the document is counted.

In the figure, components having the same configuration as in FIG. 4 are denoted by the same reference numerals as in FIG. Reference numeral 20101 denotes a counter, which counts the number of fluorescent pixels from a document based on CLK. In this embodiment, an 8-bit counter is used to integrate up to 255 fluorescent pixels. Reference numeral 20202 denotes a 4-input AND gate, which includes a main scanning section signal VE and a sub-scanning section signal VSYN.
A binarized fluorescence signal output from the binarization circuit 4009 when C is generated is given as an enable signal of the counter 20101. The counter 20101 is a CPU
The flip-flop (F / F) 20103 is set by this clear signal, and the output from the gate 20102 is made valid.

When the binarized signal is input exceeding the maximum count 255 of the counter 20101, an RC signal is generated when the output of the counter 20101 reaches 255, the F / F 20103 is reset, and the counter of the counter 20101 is reset. The enable input is forcibly set to "0" and the output of the counter is held at 255.

The CPU 417 reads the count result of the counter 20101 as a CNT signal, and detects that a copy-inhibited document is being copied when the count result is equal to or more than a predetermined value (for example, 128 pixels or more).

FIG. 26 shows a processing flow of the CPU in this embodiment.

At step 20201, the CPU sets the counter 2
0101 and F / F 20103 are cleared.

In step 20202, the first scan is started. Here, the printer outputs magenta and counts the number of pixels of the fluorescence information from the document.

Next, in step 20203, it is detected whether or not the number of fluorescent pixels is equal to or more than a predetermined value (128).
If there is no possibility of forgery, that is, if the number of fluorescent pixels is equal to or less than a predetermined value,
In 204, 2nd scan, 3rd scan, 4t
The h scan is performed, developed by four colors of M, C, Y, and Bk toners in a normal operation, and is fixed and output in 20205.

On the other hand, if it is determined in step 20203 that there is a possibility of forgery, and if a predetermined number or more of fluorescent pixels are detected, counterfeit prevention measures are taken in step 20206. Specifically, by setting FFH to the register 408 in FIG. 4 (usually 00H is set), FFH is sent to the printer unit, and the C, Y, and Bk toners adhere to the entire surface. Can not be copied.

<Third Embodiment> In this embodiment, as in the second embodiment, the presence of fluorescent light is detected instead of the form of infrared fluorescent information in a copy-inhibited document.

In this embodiment, the presence of a fluorescent mark other than visible light, such as infrared light, included in a copy-inhibited original is detected, and the fluorescent information is converted into visible information, and the visible record information from the original is detected. It is recorded together with. This prevents a normal copy operation of a copy-inhibited document.

The fluorescent information of the copy-inhibited document valid in this embodiment is a material in which a regular pattern as shown in FIG. 27 is recorded on the entire surface of the document, or a material in which the entire surface of the document is filled with the fluorescent information. Is good. Usually, as long as the fluorescent information shows a characteristic that is transparent to visible light, it does not pose a practical problem in normal use other than illegal copy use.

FIG. 28 shows a control block in this embodiment. Here, as in FIG. 25, instead of performing the pattern matching of the fluorescent mark, the number of pixels of the fluorescent information included in the document is counted. In the figure, the same configuration as FIG.
The same number as 5 is assigned.

20401 is an AND gate, and 204
02, a signal obtained by converting the intensity of the infrared fluorescence read signal IR into a light amount is made valid by a P-ENB signal from the CPU 417,
An OR gate 407 combines the image with a normal visible recorded image.
The IR signal is corrected by a delay means 401 so that the CCD reading phase shift with the visible information in the sub-scanning direction is corrected. For example, when fluorescent information is printed on a copy-inhibited document, moire fringes and the like are generated by the fluorescent information and the visible information. If it is generated, the effect of preventing copy due to the intended moire or the like can be effectively utilized.

The CPU 417 reads the count result of the counter 20101 as a CNT signal, and detects that a copy-inhibited document is being copied when the count result is equal to or more than a predetermined value (for example, 128 pixels or more).
By making the signal “1”, the infrared fluorescence information is visualized,
Block normal copy operations.

FIG. 29 shows a processing flow of the CPU in this embodiment.

At step 20501, the CPU sets the counter 2
0101 and F / F 20103 are cleared, and the P-ENB signal is set to “0”.

At step 20502, the first scan is started. Here, the printer outputs magenta and counts the number of pixels of the fluorescence information from the document.

Next, in step 20503, it is detected whether or not the number of fluorescent pixels is equal to or more than a predetermined value (128).
If it is determined in 20503 that there is no possibility of forgery, that is, if the number of fluorescent pixels is equal to or less than a predetermined value, 20
In 504, 2nd scan, 3rd scan, 4t
The h scan is performed, developed by four colors of toners of M, C, Y, and Bk in a normal operation, and is fixed and output at 20505.

On the other hand, if more than a predetermined number of fluorescent pixels are detected in 20503 and it is determined that there is a possibility of forgery, counterfeit prevention measures are taken in 20506. More specifically, the P-ENB signal is set to "1", and a recorded image in which the fluorescent information is synthesized at the time of recording C, Y, and Bk is sent to the printer unit. As a result, a normal copy operation cannot be performed.

<Other Embodiments> In the above embodiment,
The infrared light component near about 700 nm is used as the excitation light as the excitation light, and infrared fluorescence having a peak at about 800 nm is emitted from the recognition mark. However, light in the visible light range is used as the excitation light. For example, information indicating a copy-inhibited document may be configured by fluorescent ink so that infrared fluorescent light of 700 to 800 nm is emitted.

In this case, in the above embodiment, R,
A filter for cutting infrared light shown in FIG. 20 is provided as a filter for the G and B reading CCDs.
A filter that cuts 0 nm or more is used.

As a result, the light input to the R, G, and B line sensors is only infrared light from the recognition mark of the copy-inhibited original or a special case of emitting similar infrared fluorescent light. R, G, B reading CCD as in the example
It is not necessary to provide a characteristic of cutting infrared light including near infrared of 650 nm or more, and the cost of the CCD can be reduced.

Further, information indicating a copy-inhibited document may be constituted by fluorescent ink using, for example, light in the ultraviolet light range as excitation light and emitting, for example, infrared fluorescence of 700 to 800 nm.

In this case, as compared with the first embodiment, a light source such as a metal halide lamp having a light emitting component also in the ultraviolet region is used as a light source, and a filter 208 for cutting off infrared rays in the light source is used as shown in FIG. By using a filter that cuts the characteristic of 650 nm or more, direct reflection light of infrared light from the light source is not incident on the R, G, B and IR sensors. The spectral characteristic of the original illumination light is thereby represented by reference numeral 206 in FIG.
01. The filter of the CCD for reading R, G, and B has the spectral characteristics of R, G, and B shown in FIG. A filter having the characteristics described above is provided. FIG. 16 shows the IR sensor.
Only the ultraviolet fluorescent component is read using a filter having a characteristic of cutting the visible component and the ultraviolet component. Then, a higher level of infrared fluorescence 20603 is obtained by using a short-wavelength ultraviolet excitation light 20602 having light energy relatively larger than visible or infrared light.
This enables more reliable recognition of the fluorescent mark (recognition mark).

The CCD shown in FIG. 15 is not limited to reading infrared fluorescent light and visible information, and is similarly used for reading visible information and infrared information. A sensor for reading infrared light having a thick light-receiving layer is provided outside the sensor for reading visible information.

The CCD shown in FIG. 15 is not limited to reading infrared light other than visible light and visible information, and is similarly used for reading ultraviolet light information other than visible light and visible information. That is, in order to effectively read short-wavelength ultraviolet information, in the cross-sectional structure diagram of the sensor shown in FIG. 17, the thickness of the photoelectric conversion layer composed of the p-layer contributing to photoelectric conversion and the n-layer above it is reduced. Must be set. For this reason, it is necessary to surely separate the photodiode and the charge transfer section which is generally formed on both sides of the photodiode and perform the serial operation, and suppress electric induction. Therefore, the interval between the ultraviolet light reading sensor and the other line sensors is configured to be wider than the other sensor intervals. Further, a sensor having a different structure of the light receiving layer is formed outside the other sensors to simplify the structure of the CCD.

The CCD shown in FIG. 15 is not limited to reading infrared fluorescent light and visible information, and is similarly used for reading visible information and ultraviolet, visible, and infrared fluorescent information. . That is, a fluorescent reading sensor is provided outside of a plurality of line sensors for reading weak fluorescent information, or a line interval is set wider than a line interval between other sensors, so that crosstalk from information other than fluorescent information is reduced. Hold on. The infrared light is read outside the sensor for reading visible information.

In all of the above embodiments, a common illumination system is provided for reading visible information and exciting fluorescence. However, this may be combined with illumination lamps having different characteristics to emit light. Examples of this combination include an FL lamp for visible light and a halogen lamp for infrared excitation light, a halogen lamp for reading visible light and an FL lamp (black lamp) for generating only ultraviolet excitation light.

In the above-described embodiment, the correction of the visible light reading data and the correction of the infrared light fluorescence data are performed by the standard white plate. The reference plates to be corrected may be independently prepared at different locations.

The same reference plate may be a white reference plate with visible light and an infrared fluorescent material showing almost transparent characteristics in a visible state.

As described above, according to the above-described embodiment of the present invention, the specific original is detected by using the fluorescence information indicating the substantially transparent characteristic with visible light, thereby affecting the actual use state with visible light. A copy-inhibited document can be detected without giving it.

Further, since the document information is determined by using information other than the visible information, the information included in the document for the determination cannot be determined when it is visible, and cannot be determined by ordinary image reading means. Therefore, it is possible to further enhance the confidentiality with respect to the copy prohibition operation of the copy prohibition document. Furthermore, since a specific document is identified using information other than visible information compared to visible information, it is possible to intentionally reduce information that is confusing with identification information as compared with the case where visible information is used. The document can be identified.

In addition, by recording information that cannot be identified by visible light as visible information, it is possible to easily identify an illegally copied material from a copy-inhibited document.

Further, since the visible information and the non-visible information are read simultaneously, and the document is determined using the non-visible information, the document is discriminated in real time with respect to the image data output operation. Since the accuracy of document discrimination can be improved, a copy prohibition operation on a copy-prohibited document can be further effectively realized.

Further, the non-visible information of the copy prohibited document is converted into visible information in real time while the visible information is being output.
It is possible to output together with the visible information from the original, and it is possible to prevent complete output of visible data from the copy-inhibited original with simple control.

Further, the illumination for reading the visible information and the non-visible information is shared, and the visible information and the non-visible information are separated by independent sensors. Is improved with a simple configuration. Further, since the sensors are provided independently for visible and non-visible, the gain for each read signal can be set optimally.
As a result, the S / N ratio of each of the visible information and the information other than the visible information can be optimized, so that it is effective to achieve both high-quality original reading and highly accurate original discrimination with a simple configuration.

Further, by providing a filter for passing the excitation wavelength component of the fluorescent component to be detected and attenuating the fluorescent wavelength component in the optical path from the document illumination lamp to the document,
It is possible to read fluorescent information having a good S / N ratio.

Further, by providing a filter for cutting non-visible wavelengths after a common optical system of visible light and non-visible light and before a sensor for reading visible light, the influence of non-visible light can be reduced. It is possible to read the visible information without.

Further, by providing a filter that cuts excitation light or visible light for fluorescence after a common optical system for visible light and non-visible light, and before a sensor for reading non-visible light, Light other than visible light having a good / N ratio can be read.

Further, it is possible to reliably detect the copy prohibition information by using the fluorescence information generated by illumination with a large amount of infrared light such as a conventionally used halogen lamp.

Further, by forming the sensor for detecting non-visible light information and the sensor for reading visible information in a monolithic manner, it is necessary to secure a light path using a special optical system such as a prism for reading non-visible information. Therefore, accurate reading of non-visible light at the same document position with a simple optical system is possible, and forgery prevention such as synthesis of recognition marks and document information can be realized with high accuracy.

By changing the thickness of the light receiving layer of the sensor for reading non-red and visible light information monolithically constructed with the visible sensor to a visible object, good visible reading and good non-visible reading can be achieved. Can be realized on the same chip.

Further, the thickness of the light-receiving layer can be changed between visible and non-visible by making the line interval between the sensor for reading light information other than visible light and the sensor for reading other visible light wider than other line intervals. For example, the configuration of the CCD for dealing with wavelengths other than visible light can be easily complicated, and the yield of the CCD can be improved.

In addition, the sensor for reading non-visible light is provided at the outermost of a plurality of sensor lines, so that the thickness of the light-receiving layer can be changed between visible and non-visible. Therefore, it is easy to cope with the complicated configuration of the CCD, and the yield of the CCD is improved.

Further, since the sensor for detecting the fluorescence information is monolithically configured with the sensor for reading the information other than the fluorescence, it is not necessary to secure an optical path using a special optical system such as a prism for reading the fluorescence information. This makes it possible to read fluorescence information with high accuracy at the same document position with a simple optical system, and it is possible to accurately combine document information with a recognition mark.

By making the light receiving area of the sensor for reading the fluorescence information larger than that of the sensor for reading the visible light, even the minute non-visible light information generated by the fluorescence has the same S / S as the visible light. High-quality reading with a good N ratio becomes possible.

Further, by constructing a sensor for reading fluorescent light on the outermost side of a plurality of sensor lines, a weak read signal of fluorescent light has a relatively large signal level such as crosstalk of a visible read signal. The influence can be reduced, and highly accurate fluorescence reading can be performed.

Further, by setting the line interval between the sensor for reading fluorescence and the sensor for reading other visible light wider than other line intervals, the signal level of a weak read signal such as fluorescent light is relatively large. The effect of a visible read signal can be reduced, and highly accurate fluorescent reading can be performed.

Further, by providing a standard density unit for correcting sensitivity unevenness due to a main scanning position due to uneven light distribution or the like to a read signal of a sensor for reading optical information other than visible, common to a visible object, the standard density means is provided. The size can be reduced.

Also, by using a read signal from a reference density plate for signal correction for a sensor for reading fluorescent information, a circuit gain of the fluorescent read signal is set, and sensitivity unevenness of the fluorescent read sensor is corrected. It is possible to optimally set the dynamic range of read signals other than visible, and there is no overflow equivalent to visible,
Further, it is possible to read the fluorescence information with a high S / N ratio.

Also, using a read signal from a reference density plate for signal correction for a sensor for reading non-visible optical information, a circuit gain of a non-visible read signal is set, and sensitivity unevenness of the sensor is corrected. This makes it possible to optimally set the dynamic range of the non-visible read signal, and to read non-visible optical information having a high S / N ratio without overflow or the like equivalent to the visible signal.

[0184]

As described above, according to the present invention, information other than invisible information can be generally obtained by setting a line interval between an invisible reading sensor for reading weak information to be wider than a line interval between other sensors. This makes it possible to suppress crosstalk from the user and to efficiently read invisible information with high quality. Furthermore, by configuring the sensor for detecting non-visible light information and the sensor for reading visible information in a monolithic manner, there is no need to secure an optical path using a special optical system such as a prism for reading non-visible information. In addition, accurate reading of non-visible light at the same document position with a simple optical system is possible.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a detection state of an identification mark of a copy-inhibited document in a first embodiment.

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

FIG. 3 is a diagram showing an operation of detecting a copy-inhibited document in the first embodiment.

FIG. 4 is a configuration diagram of a signal processing unit according to the first embodiment.

FIG. 5 is a timing chart of an image control signal in the first to third embodiments.

FIG. 6 is a block diagram of noise removal of a fluorescence signal in the first embodiment.

FIG. 7 is a block diagram for detecting a position of a fluorescent mark in the first embodiment.

FIG. 8 is an address generation unit for a memory that stores a fluorescent mark in the first embodiment.

FIG. 9 is a control flowchart of the CPU according to the first embodiment.

FIG. 10 is an operation flowchart of pattern matching of the CPU according to the first embodiment.

FIG. 11 is a diagram illustrating a thinning operation of a fluorescent mark according to the first embodiment.

FIG. 12 is a schematic diagram of pattern matching of a fluorescent mark in the first embodiment.

FIG. 13 is a spectral characteristic diagram of a filter immediately after a document illumination lamp in the present embodiment.

FIG. 14 is a spectral characteristic diagram of a document illumination lamp according to the present embodiment.

FIG. 15 is a configuration diagram of a CCD sensor in the present embodiment.

FIG. 16 is a filter characteristic diagram for an infrared reading sensor in the present embodiment.

FIG. 17 is a schematic diagram of photoelectric conversion of a CCD in the present embodiment.

FIG. 18 is a spectral sensitivity characteristic diagram of a CCD according to the present embodiment.

FIG. 19 is a spectral sensitivity characteristic diagram of the visible line sensor in the present embodiment.

FIG. 20 is a spectral sensitivity characteristic diagram of the visible line sensor in the present embodiment.

FIG. 21 is an analog signal processing unit according to the present embodiment.

FIG. 22 is a control flow of dimming and circuit gain in the present embodiment.

FIG. 23 is a light amount control block of a document illumination lamp in the present embodiment.

FIG. 24 is a fluorescence characteristic diagram in this example.

FIG. 25 is a configuration diagram of a signal processing unit according to the second embodiment.

FIG. 26 is a control flowchart of the CPU according to the second embodiment.

FIG. 27 is a diagram illustrating a printing state of fluorescent information of a copy-inhibited document in the third embodiment.

FIG. 28 is a configuration diagram of a signal processing unit according to the second embodiment.

FIG. 29 is a control flowchart of the CPU according to the second embodiment.

FIG. 30 is a characteristic diagram of infrared fluorescence by ultraviolet excitation light.

FIG. 31 is a characteristic diagram of a standard white plate used in this example.

[Description of Signs] 210 CCD line sensor 409 8 × 8 block processing circuit 410 Fluorescent mark detection circuit 4009 Binarization circuit

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Tsutomu Utagawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Toshio Hayashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Tetsuya Nagase 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Takehiko Nakai 3-30-2, Shimomaruko 3-chome, Ota-ku, Tokyo Canon Inc. ( 56) References JP-A-2-266655 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 1/04-1/207 G06T 1 / 00,1 / 60

Claims (3)

(57) [Claims] A first plurality of line sensors corresponding to a plurality of different colors for obtaining visible information; and a second line sensor for obtaining invisible information, wherein the first plurality of line sensors are provided. The second line sensor is disposed at a position separated by a distance L2 greater than the distance L1 between the first and second line sensors, and the first plurality of line sensors and the second line sensor are monolithically configured. Image processing device. 2. The image processing apparatus according to claim 1, wherein the invisible information is infrared information. 3. The image processing apparatus according to claim 1, wherein the invisible information is information based on fluorescence.