TWI739337B - Paper discriminating device, white reference data adjustment method, program, and calibration method - Google Patents

Abstract

The subject of the present invention is to appropriately shading and correct the image of the paper.

The solution of the present invention is to provide: light receiving means, which is arranged at a position opposite to the other side of the moving paper to receive the detection light passing through the paper, and along the width direction orthogonal to the moving direction of the paper It is equipped with a plurality of pieces; and an image data generating means, which is used to generate image data corresponding to the level of the detection light that has been incident on the light receiving means; and a white reference data memory means, which memorizes the white reference data, the white The reference data is obtained by irradiating the detection light on the white reference member used for the shading correction of the image data. In the above configuration, it is equipped with: movement restricting means, which is located at the end of the conveying path in the width direction and forming the side wall of the conveying path; and adjustment means, which is determined in advance by the position of the light receiving means in the width direction In a specific area as a condition, the white reference data of the image data used for the shading correction of the light receiving means is adjusted to a predetermined value.

Description

Paper discriminating device, white reference data adjustment method, program, and calibration method

The invention relates to a paper identification device, a method for adjusting white reference data, and a program.

In the past, there has been known a paper discriminating device that accepts paper inserted from the insertion port into the conveying path and performs discriminating processing such as authenticity of the paper, currency type, and the like. In the above paper identification device, the paper being conveyed to the conveying path is captured by an image sensor, and image data representing the paper is generated. The above image data is used to identify the authenticity of the paper.

For example, Patent Document 1 discloses a paper discriminating device equipped with an image sensor. The image sensor is composed of a light-emitting means and a light-receiving means. One side irradiates the detection light, and the light receiving means allows the detection light that penetrates toward the other side of the paper to enter. Among the above paper discriminating devices, in some cases, a shading correction technique is used to correct the image generated by the image sensor.

[Prior Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent Application Publication No. 2009-295125

The white reference data used for shading correction is generated by a predetermined method. However, there will be the following situations: it is difficult to properly generate white reference data by the method of generating white reference data (for example, the shape of the white reference member), and the white reference data is used to calibrate the specific area determined in advance (For example, the image data of the pixels near the side wall of the conveying path). Considering the above situation, the purpose of the present invention is to be able to adjust the white reference data of the pixels located in the above-mentioned specific area.

In order to solve the above problems, it is provided with: a conveying means, which moves the paper along a conveying path; and a light emitting means, which irradiates a detection light toward one surface of the moving paper; and a light receiving means, which is arranged in and moving The opposite side of the paper is used to receive the detection light from the paper, and a plurality of them are arranged along the width direction orthogonal to the moving direction of the paper; and the image data generating means, which is used to generate and The image data corresponding to the gradation of the detection light that has been incident on the light receiving means; and the white reference data memory means, which memorize the white reference data, which is used to correct the image data for shading The white reference member is obtained by irradiating the detection light; and the movement restricting means, which is located at the end of the conveying path in the width direction, and forming the side wall of the conveying path; and the adjustment means, which is based on the width direction position of the light receiving means. The determined specific area is the condition, and the white reference data of the image data used for the shading correction of the light receiving means is adjusted to a predetermined value.

According to the present invention, the image of the paper can be shadingly corrected appropriately.

[First Embodiment]

Fig. 1(a) is a perspective view of the appearance of the banknote identification device H of the first embodiment. In addition, Fig. 1(b) is a cross-sectional view taken along the line A-A in Fig. 1(a). The above paper money identification device H is equipped with CPU (Central Processing Unit; Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory; random access memory) and flash memory (flash memory) and other control devices.

As shown in Fig. 1(a), the banknote identification device H is composed of a lower unit 1 and an upper unit 2, and is formed between the upper surface of the lower unit 1 and the lower surface of the upper unit 2 for the conveyance path 4, Insert paper (for example, banknotes) from the insertion port 3a. The banknotes inserted in the insertion port 3a are moved into the conveyance path 4 toward the movement direction shown by the arrow in FIG. 1(b).

As shown in FIG. 1(b), the paper money identification device H is provided with a conveying device 5. The conveying device 5 is composed of a plurality of lower conveying members 5a and upper conveying members 5b. )), a conveying belt, etc., and the upper conveying member 5b is arranged on the upper side of the conveying path 4 and is constituted by conveying rollers etc. arranged opposite to the respective lower conveying members 5a. The lower conveyance member 5a of this example is a conveyance roller, a conveyance belt, etc. which are driven by a motor while contacting the lower surface of the banknote with its outer peripheral surface. The upper conveying member 5b is in contact with the upper surface of the banknote with its outer peripheral surface, and rotates together with the lower conveying member 5a through the banknotes. The banknotes inserted in the insertion port 3a are arranged between the lower conveying member 5a and the upper conveying member 5b, are sandwiched on both sides, and move to the conveying path 4 at a fixed speed as the lower conveying member 5a rotates. In addition, the conveying device 5 for conveying banknotes is not limited to the above-mentioned example.

As shown in FIG. 1(b), the banknote identification device H includes sensors 6 (6a, 6b, 6c). The control device of the paper money identification device H performs identification in response to information obtained from the sensor 6 on the authenticity of the paper money inserted into the insertion port 3a. Specifically, the sensor 6 is composed of two image sensors 6 (6a, 6b) and a magnetic sensor 6c. However, it can also be set as the structure which discriminates banknotes by the sensor other than the above-mentioned sensor.

The first image sensor 6a is a CIS (Contact Image Sensor; contact image sensor). In addition, the second image sensor 6b is a CIS similar to the first image sensor 6a. Each of the above image sensors includes a light-emitting part (for example, the light-emitting element Ga described later) and a light-receiving part (for example, the pixel Gb mentioned later). The light receiving part is for the detection light to enter. In addition, the light-emitting part of the image sensor includes two types of light sources: a reflective light source and a penetrating light source. Each light source irradiates a plurality of types of detection light with different wavelengths. Furthermore, the "detection light" in the present invention can include invisible light (infrared light, etc.) in addition to visible light (wavelength=360nm to 760nm).

For example, the detection light irradiated from the reflected light source of the first image sensor 6a is reflected on one side of the banknote in the conveying path 4 and enters toward the light receiving part of the first image sensor 6a. In addition, the detection light irradiated from the reflected light source of the second image sensor 6b is reflected on the other side of the banknote in the conveying path 4, and enters toward the light receiving part of the second image sensor 6b.

The detection light irradiated from the penetrating light source of the first image sensor 6a penetrates from one side of the banknote in the conveying path 4 to the other side, and faces the light-receiving part of the second image sensor 6b Incident. In addition, the detection light irradiated from the penetrating light source of the second image sensor 6b penetrates from the other side of the banknote in the conveying path 4 toward one side, and faces the first image sensor 6a. The light receiving part is incident.

The light receiving part of the image sensor (6a, 6b) is composed of a plurality of pixels. In addition, a detection signal corresponding to the detection light (transmitted light, reflected light) that has been incident on the above pixels is input to the above-mentioned control device. The CPU of the control device executes the program stored in the ROM to generate image data representing the banknote based on the detection signal.

According to the image data, black correction processing to remove dark current components is performed. Also, although the details will be described later, after performing the black correction processing, the shading correction is performed on the image data. The so-called shading correction refers to the method of reducing the uneven brightness contained in the image data, for example, by dividing the level of each pixel of the white reference data by the level of each pixel of the corresponding image data to correct The method of the level of each pixel of the image data. The white reference data used for shading correction is, for example, generated during the manufacturing process of the banknote identification device H and stored in the flash memory of the control device.

The magnetic sensor 6c detects the iron component contained in the ink on the printing surface of the banknote. The CPU uses the detection signal from the above sensor 6 to identify banknotes. For example, in a case where it has been determined that it is not a legal banknote, the banknote is discharged from the insertion port 3a by the conveying device 5. On the other hand, when it has been judged to be a legal banknote, the banknote moves toward the intake port 3b. Although detailed description is omitted, the banknote identification device H is installed in, for example, a paper processing device described in Japanese Patent Application Laid-Open No. 2009-295125. The banknotes moved toward the intake port 3b of the banknote discriminating device H are then accommodated in the accommodating unit of the paper processing device.

Fig. 2(a) is an exploded perspective view of the banknote identification device H. In addition, Fig. 2(b) is a cross-sectional view taken along the line B-B in Fig. 1(a) described above. As shown in Figure 2(a), the banknote identification device H includes the lower unit 1, the upper unit 2, the first image sensor 6a, and the second image sensor 6b, and also includes a lower cover ) 7. Upper tray 8, white reference sheet 9 for reflection (9a, 9b). Furthermore, in FIG. 2(b), the first image sensor 6a, the second image sensor 6b, the lower cover 7, the upper holder 8 and the reflector among the various components of the banknote identification device H are omitted. Display with a structure other than the white reference sheet 9 (9a, 9b).

As shown in Fig. 2(a), the upper bearing plate 8 is formed in a substantially box shape with a bottomed recess 8a on the upper surface. As shown in Fig. 2(b), the upper bearing plate 8 is housed in the recess 8a There is a first image sensor 6a. Furthermore, as shown in FIG. 2(b), the lower surface 8b of the upper support plate 8 forms the upper surface (top surface) of the conveyance path 4. The above upper support plate 8 is formed of a light-transmitting material, such as a transparent resin.

Fig. 2(b) shows a plurality of light-emitting elements Ga as the penetrating light source of the first image sensor 6a. Furthermore, in FIG. 2(b), a part of all the light-emitting elements Ga is selected and displayed. The above light-emitting element Ga is based on the X-axis direction (width direction) perpendicular to the horizontal direction with respect to the Y-axis direction when the direction in which the banknotes move in the conveying path 4 is taken as the Y-axis direction (conveying direction) Extend multiple ways to configure. In this embodiment, 720 light-emitting elements Ga are arranged in the X-axis direction.

As shown in FIG. 2(b), the first image sensor 6a is housed in the recess 8a of the upper support plate 8 in such a way that the light emitting element Ga is located on the side of the lower surface 8b. As mentioned above, the upper bearing plate 8 is light-transmissive. Therefore, the detection light irradiated from the light-emitting element Ga can penetrate the upper holder 8 and enter toward the conveyance path 4.

As shown in FIG. 2(b), the second image sensor 6b of this embodiment includes a plurality of pixels Gb into which the detection light irradiated from the first image sensor 6a enters. Furthermore, in FIG. 2(b), a part of all the pixels Gb is selected for display. The above second image sensor 6b is provided with the same number (720) of pixels Gb as the light-emitting elements Ga of the first image sensor 6a. In addition, each pixel Gb is arranged in the X-axis direction similarly to the light-emitting element Ga, and one light-emitting element Ga and one pixel Gb face each other so that the optical axis L (see FIG. 2(b)) coincides.

As shown in Figure 2(a), the lower cover 7 is provided with a right side wall 7a, a left side wall 7b, a recess 7c, and an upper surface 7d. The recess 7c is along the inner end edge of the lower cover in the conveying direction A notch is formed and penetrates in the up-down direction, and the upper surface 7d is located at a position where the recess 7c has been avoided. As shown in FIG. 2(b), the lower cover 7 is arranged to cover the upper surface (the pixel Gb side) of the second image sensor 6b. In addition, the upper surface 7d of the lower cover 7 constitutes the bottom surface of the conveyance path 4. The height (distance h shown in FIG. 2(b)) from the bottom surface (lower cover 7) to the top surface (upper tray 8) of the conveyance path 4 in this embodiment is about 2 mm.

When the lower cover 7 is installed on the lower unit 1, the lower conveying member 5a such as the conveying belt of the conveying device 5 protrudes toward the conveying path 4 side through the recess 7c. The banknotes in the conveying path 4 move in the conveying direction along with the rotation of the conveying belt.

The lower cover 7 is formed of a light-transmitting material, such as transparent resin, similarly to the above-mentioned upper receiving plate 8. Therefore, the detection light irradiated from the light-emitting element Ga of the first image sensor 6a and penetrating the paper money in the conveying path 4 can penetrate the lower cover 7 (upper surface 7d) and be incident on the second The pixel Gb of the image sensor 6b.

As shown in FIG. 2(b), the right side wall surface 7a and the left side wall surface 7b of the lower cover 7 form the side walls of the conveyance path 4. Specifically, the right side wall 7a forms a right side wall when viewed from the banknotes moved to the conveyance path 4. In addition, the left side wall surface 7b forms a left side wall when viewed from the banknotes moved to the conveyance path 4. In this embodiment, for the sake of description, the area from the right wall surface 7a to the left wall surface 7b among the areas on the X axis (main scanning axis) is referred to as "area R". The above area R refers to the area used for imaging the banknotes.

In the present embodiment, the length of the region R (the distance from the right wall surface 7a to the left wall surface 7b) is only about 4 mm longer than the width of the banknotes moving to the conveyance path 4 in the X-axis direction. In the above configuration, the width of the conveying path 4 becomes shorter than the configuration in which the length of the region R is longer than the width of the banknote by 4 mm or more, for example. Therefore, according to the present embodiment, there is an advantage that the paper money identification device H can be easily downsized.

As described above, the banknote identification device H of this embodiment is capable of performing shading correction of images. Specifically, the paper money identification device H is capable of performing both the shading correction of the image obtained by the reflected light source and the shading correction of the image obtained by the penetrating light source.

The banknote identification device H uses the reflected light source and the light receiving part outside the above-mentioned area R to generate white reference data used for shading correction of the image obtained by the reflected light source. On the other hand, the white reference data used for shading correction of the image obtained by the penetrating light source (light emitting element Ga) is generated using the penetrating light source and the light receiving portion (pixel Gb) inside the region R described above.

The banknote identification device H is equipped with white reference sheets (9a, 9b) for reflection in order to generate white reference data used for shading correction of an image obtained by a reflected light source. As shown in FIG. 2(a), two white reflection plates T are provided on the above white reference sheet 9 for reflection. As shown in FIG. 2(b), the white reference sheet 9 for reflection is installed so that the reflection plate T is located in the region r outside the region R. As shown in FIG. Furthermore, as shown in FIG. 2( b ), the front end of each reflector T abuts against the lower cover 7. In this embodiment, the pixels Gb are arranged in the entire area of the area R and the area r.

One of the two reflective plates T can be irradiated with light emitted from the reflective light source located in the region r among the reflective light sources of the first image sensor 6a. In addition, the light emitted from the above reflective light source and reflected on the reflector T is a light receiving element (pixel) for reflected light incident on the first image sensor 6a. Similarly, the other reflective plate T among the two reflective plates T can be irradiated by the light emitted from the reflective light source located in the region r among the reflective light sources of the second image sensor 6b. In addition, the light emitted from the above reflective light source and reflected on the reflector T is a light receiving element (pixel) for reflected light incident on the second image sensor 6b. The CPU of the control device generates white reference data for correcting the image obtained by the reflected light source according to the degree of the reflected light from the reflector T that has been incident on the light receiving element.

As described above, the white reference data of the image obtained by the reflected light source is generated using the white reference sheet 9 for reflection (reflection plate T). On the other hand, the white reference data of the image obtained by the penetrating light source (light emitting element Ga) is generated using the white reference member 10 (refer to FIG. 3) described later. Furthermore, the time period for generating the white reference data of the image obtained by the reflected light source can be appropriately set. For example, just after the banknote is inserted into the insertion port 3a (before the banknote is detected by the image sensor), the above white reference data may be generated.

Fig. 3(a) is a perspective view of the white reference member 10 described above. In this embodiment, the white reference member 10 is used to generate the white reference data during the manufacturing process of the banknote identification device H. However, the white reference data may be generated at another timing. The white reference member 10 is arranged on the conveyance path 4 (the upper surface 7d of the lower cover 7) when the white reference data is generated (refer to FIG. 3(b) described later). In addition, the white reference member 10 is removed by the operator after the white reference data is generated. That is, when the banknote identification device H is shipped as a finished product, the white reference member 10 is not arranged in the conveyance path 4.

As shown in FIG. 3(a), the white reference member 10 is composed of a white reference sheet 10a and a rectangular ring-shaped guard member 10b that holds the outer periphery of the white reference sheet 10a. The white reference sheet 10a penetrates the same light (type and intensity) as the white part of the banknote when the detection light of the light-emitting element Ga has been irradiated. The above-mentioned white reference sheet 10a is formed of, for example, approximately the same thickness as a banknote.

The shield member 10b is a substantially plate-shaped ring-shaped member (housing) with a substantially rectangular outer edge, and as shown in FIG. 3(a), a penetrating opening K is provided. The white reference sheet 10a is attached (attached) to the protection member 10b so as to block the opening K. The protective member 10b is formed of a material with a higher strength and a larger specific gravity (heavier) than the white reference sheet 10a. For example, the protective member 10b is formed of an alloy such as stainless steel.

According to the white reference member 10 provided with the protection member 10b, compared with, for example, the white reference member 10 composed of only the white reference sheet 10a, there is the following advantage: when the white reference member 10 is arranged in the conveyance path 4, The bending defect of the white reference sheet 10a can be suppressed. In addition, there is an advantage that the defect that the white reference member 10 (white reference sheet 10a) deviates due to the influence of wind can be suppressed.

FIG. 3(b) is a schematic diagram for explaining the white reference member 10 that has been placed on the conveyance path 4. In the case of generating white reference data, the white reference member 10 can be temporarily arranged on the conveyance path 4 by an operator. Specifically, the white reference member 10 is arranged between the first image sensor 6a and the second image sensor 6b, and is arranged for detecting that the light-emitting element Ga of the first image sensor 6a has been illuminated. The location of the light.

As shown in FIG. 3(b), the length of the long side of the white reference member 10 is approximately (approximately equal) to the length of the region R. In the above case, the short side of the white reference member 10 (protection member 10b) is located (approximately abutting) near the side walls (7a, 7b) of the conveyance path 4. In addition, the structure of the white reference member 10 is not limited to the above-mentioned example.

When generating white reference data, in a state where the white reference member 10 has been placed in the area R of the conveyance path 4, detection light is irradiated from the light-emitting element Ga. In the above case, among the detection light from the light-emitting element Ga, the detection light that has been irradiated on the white reference sheet 10a of the white reference member 10 penetrates the white reference sheet 10a and is incident on the pixel Gb. From the detection light incident on the above pixel Gb, an appropriate white reference data is generated.

On the other hand, in the white reference member 10, the protective member 10b has a lower light transmittance than the white part of the banknote (the white reference sheet 10a). For example, when the protective member 10b is made of metal, the detection light will not pass through. Therefore, in the state where the white reference member 10 has been installed in the region R, the detection light is irradiated from the light-emitting element Ga of the first image sensor 6a, and has been irradiated to the protective member 10b (at both ends in the longitudinal direction) The detection light of the portion 10b′) does not pass through the second image sensor 6b, so it is not received by the pixel Gb. In the above case, the white reference data (refer to FIG. 5(b) described later) for shading correction of the pixel data already generated for the pixel Gb cannot be appropriately generated.

As understood from the above description, when the white reference member 10 of this embodiment is used to generate white reference data, it is impossible to properly generate pixels for correcting the opposite ends 10b' of the protection member 10b in the longitudinal direction. The white reference data of the Gb image. That is, the white reference data of the pixel Gb located near the side wall of the conveyance path 4 cannot be appropriately generated. In the case where the white reference data of the pixels Gb located near the side wall of the conveying path 4 cannot be properly generated, for example, as shown in FIG. Become a problem.

For example, in the past, ATM (Automatic Teller Machine; automatic teller machine) devices, etc., have adopted a technology that sprays stolen ink on the banknote when the banknote is illegally taken out (stolen) (for example, refer to Japanese Patent Publication 2000 -Bulletin No. 322625). Based on the above situation, in the banknote discriminating device H, a preferable configuration is capable of determining whether or not stolen ink has adhered to the inserted banknote. However, there are many cases where the stolen ink adheres to a location near the outer edge of the banknote in the width direction. Therefore, if the shading correction of the image taken near the side wall of the conveyance path 4 cannot be performed properly, there are cases in which it is impossible to accurately determine whether the stolen ink has adhered to the banknote.

Considering the above situation, the banknote identification device H of the present embodiment is provided with a structure in which the image near the side wall of the conveying path 4 can be appropriately shaded (the white reference data generating unit 107 shown in FIG. 4 described later). According to the above banknote identification device H, there are advantages in that the width of the conveying path 4 is made relatively short, and at the same time, the stolen ink that has adhered to the outer edge of the banknote can be properly detected.

Specifically, the banknote discriminating device H of the present embodiment adopts the following configuration: after the white reference member 10 is used to generate white reference data, the white color of the image of the pixel Gb facing the protection member 10b can be adjusted to be adjusted. Benchmark information. According to the above structure, even if the banknote B has moved to the vicinity of the side wall of the conveying path 4, the image of the pixel Gb near the side wall of the conveying path 4 can still be shadow-corrected, so that the banknote can be identified with a clear image. B.

In addition, as another method of appropriately generating white reference data for pixels Gb near the side walls of the conveyance path 4, the following method can be considered: the both ends 10b in the longitudinal direction of the protective member 10b on which the white reference member 10 can be placed The area of 'is arranged on the outer side of the area R (outside the side wall), and the entire area of the area R is opposed to the white reference sheet 10a. However, in the above method, there may be a defect that the paper money identification device H is not easy to be miniaturized. In this embodiment, the above defects can be suppressed.

Fig. 4 is a functional block diagram of the banknote identification device 100(H) of the first embodiment. Various functions can be realized by the CPU of the banknote identification device 100 executing programs. However, in the manufacturing process of the paper money identification device 100, the paper money identification device 100 can also be connected to an external computer so as to be able to communicate, and the external computer is a part of each function shown in FIG. 4 (for example, the white reference data described later) The generating unit 107). In the above case, the combination of the paper money identification device 100 and an external computer can be equivalent to the "paper identification device" of the present invention.

As shown in FIG. 4, the banknote identification device 100 includes a transport control unit 101, a sensor unit 102, a sensor control unit 103, an image data generation unit 104, a white reference data storage unit 105, a correction unit 106, and a white reference Data generation unit 107. The conveyance control unit 101 controls the aforementioned conveyance device 5. For example, when a banknote is inserted into the insertion port 3a, the conveyance control unit 101 outputs a drive signal for rotating the conveying member 5a (conveying belt, etc.) on the lower side of the conveying device 5 so that the banknote moves in the conveying direction.

The sensor unit 102 is composed of the above-mentioned first image sensor 6a and second image sensor 6b. In addition, the sensor control unit 103 controls the lighting of the light-emitting element Ga of the first image sensor 6a. For example, the sensor control unit 103 lights the light-emitting element Ga during the period when the banknote passes through the above-mentioned region R (hereinafter referred to as the "imaging period"). In addition, the sensor control unit 103 directs the signal indicating the level of the detection light (detection light after penetrating the banknote) that has been incident on each pixel Gb at various points in the shooting period toward the image data described later The generating unit 104 inputs.

The sensor control unit 103 of the present embodiment lights the light-emitting element Ga during the period during which the white reference data is generated during the manufacturing process of the banknote discriminating device H (hereinafter referred to as "generation period"). In addition, the sensor control unit 103 is a signal indicating the level of the detection light (detection light after penetrating the white reference sheet 10a) that has been incident on each pixel Gb at each time point during the above generation period, It is input to the white reference data generating unit 107 described later.

The image data generating unit 104 generates image data representing an image of the banknote inserted into the insertion port 3a. Specifically, at each time point during the shooting period when the banknote passes through the above-mentioned region R, a signal indicating the level of the detection light (detection light after penetrating the banknote) that has been incident on each pixel Gb will be generated toward the image data部104input. The image data generating unit 104 generates image data representing the banknote based on the above-mentioned signals.

The white reference data storage unit 105 stores white reference data used for shading correction of the image data generated by the image data generation unit 104. The above white reference data is generated by the white reference data generating unit 107 described later.

The correction unit 106 uses the aforementioned white reference data to perform shading correction of the image data generated by the image data generation unit 104. Furthermore, in the banknote identification device 100, the black correction process of the image data is performed before the shading correction. Specifically, the banknote identification device 100 stores the dark current component obtained from the pixel Gb during the period when the light emitting element Ga of the image sensor (6a, 6b) is turned off. In addition, the banknote identification device 100 subtracts the aforementioned dark current component from the image data when the image data has been generated.

The white reference data generation unit 107 is composed of an adjustment position determination unit 108 and an adjustment unit 109, and generates the white reference data stored in the white reference data storage unit 105. As described above, in the white reference data generation section 107, during the generation period of the white reference data generated during the manufacturing process of the banknote discriminating device 100, the detection light that has entered each pixel Gb (after penetrating the white reference sheet 10a) The signal of the order of the detection light) is input from the above-mentioned sensor unit 102. The white reference data generation unit 107 generates the pre-adjustment white reference data based on the above-mentioned signals (refer to FIG. 5(b) described later).

The pre-adjusted white reference data refers to data that can specify the gradation of the detected light that has been incident during the generation period for each pixel Gb. The adjustment position determining unit 108 of the white reference data generating unit 107 determines the pixels Gb of the white reference data before adjustment from among the pixels Gb arranged in the scanning axis direction. Although the details will be described later, the adjustment position determination unit 108 can determine the pixel Gb facing the guard member 10b of the white reference member 10.

The adjustment unit 109 of the white reference data generation unit 107 adjusts the pre-adjustment white reference data of the pixel Gb determined by the adjustment position determination unit 108 to a predetermined value determined in advance ("average level Iave" described later). The white reference data generation unit 107 stores the white reference data adjusted by the adjustment unit 109 in the white reference data storage unit 105.

Figures 5(a) and 5(b) are schematic diagrams for illustrating the white reference data before adjustment. Fig. 5(a) is a cross-sectional view of B-B shown in Fig. 1(a) similarly to Fig. 2(b) described above. However, in FIG. 5(a), the first image sensor 6a, the second image sensor 6b, the lower cover 7 and the upper tray 8 of the respective components of the banknote identification device 100 are selected and displayed. In addition, in FIG. 5(a), the optical path of the detection light irradiated from the light-emitting element Ga is shown with a dotted arrow.

In the specific example of FIG. 5(a), it is assumed that the white reference member 10 (the white reference sheet 10a, the protection member 10b) has been arranged in the area R of the conveyance path 4. As described above, when the white reference member 10 has been placed on the conveyance path 4, the both ends 10b' in the longitudinal direction of the protection member 10b of the white reference member 10 are located on the side walls (7a, 7a, 7b) nearby.

As shown in FIG. 5(a), the detection light irradiated from the first image sensor 6a (light emitting element Ga) has been irradiated on both ends 10b' of the white reference sheet 10a in the longitudinal direction. The light penetrates the white reference sheet 10a and is incident on the second image sensor 6b (pixel Gb). On the other hand, among the detection light irradiated from the first image sensor 6a, the detection light that has been irradiated on both ends 10b' in the longitudinal direction of the protective member 10b is not directed toward the second image sensor. 6b side penetration. Therefore, the detection light that has been irradiated on both ends 10b' in the longitudinal direction of the protective member 10b does not reach the second image sensor 6b.

Figure 5(b) is a schematic diagram illustrating the white reference data before adjustment. Figure 5(b) shows the level of the detection light (transmitting light) that has been incident on the second image sensor 6b in each position on the X axis of the display area R (the area between the side walls of the conveying path 4) Degree I (brightness). In this embodiment, for the sake of explanation, the position on the X axis of the right side wall surface 7a (the right end of the region R) of the conveyance path 4 is described as "position Pea". Similarly, the position on the X axis of the left side wall surface 7b (the left end of the region R) of the conveyance path 4 is described as "position Peb".

In addition, the area on the X axis where both ends 10b' in the longitudinal direction of the protective member 10b located near the right wall surface 7a face the second image sensor 6b is referred to as "area Rx". Similarly, the area on the X axis where the protective member 10b and the second image sensor 6b located near the left wall surface 7b face the second image sensor 6b is referred to as "area Ry".

In the specific example of FIG. 5(b), it is assumed that the protection member 10b abuts on the right side wall surface 7a and the left side wall surface 7b. In the above specific example, as shown in FIG. 5(b), the coordinate system of the right end of the region Rx becomes the position Pea (common to the right wall surface 7a). Similarly, the coordinate system of the left end of the region Ry becomes the position Peb (common to the left wall surface 7b). In the specific example of FIG. 5(b), the coordinates of the left end of the area Rx are the position Px, and the coordinates of the left end of the area Ry are the position Py.

Originally, the white reference data is preferably generated by placing the white reference sheet 10a on the entire area (including the area Rx and the area Ry) of the area R, and irradiating the white reference sheet 10a with detection light. In FIG. 5(c), the white reference data generated by placing the white reference sheet 10a on the entire area of the area R is displayed.

However, as understood from FIG. 5(b) and FIG. 5(c), the level I in the region Rx and the region Ry where the protective member 10b is located is the same as the one where the white reference sheet 10a is assumed to be located in the region Rx and the region Ry. The order I of the situation is different. In the above-mentioned pre-adjusted white reference data, there may be a defect that the image data cannot be properly corrected for shading.

Considering the above situation, in the present embodiment, the level I in the adjustment region Ra including the region Rx in the region R can be adjusted. In addition, the level I in the adjustment region Rb including the region Ry in the region R can be adjusted. In addition, for the sake of explanation, there are cases in which the regions other than the adjustment region Ra and the adjustment region Rb in the region R are described as the region Rc. The entire area of the above region Rc is provided with a white reference sheet 10a (the protective member 10b is not provided).

6(a) to 6(c) are schematic diagrams for explaining the composition of the white reference data before adjustment. Fig. 6(a) shows the white reference data before adjustment in the same way as the above-mentioned Fig. 5(b). However, in the specific example of FIG. 6(a), a part of the pre-adjusted white reference data including the above-mentioned area Rx (near the side wall) and the adjustment area Ra is displayed.

As described above, the adjustment area Ra refers to the area including the area Rx where the protective member 10b is located. Specifically, as shown in FIG. 6(a), from the position Pea (the right side wall surface 7a) on the X axis to the search start position Psa is set as the adjustment area Ra. The aforementioned search start position Psa is located closer to the area Rc (white reference sheet 10a) than the left end (position Px) of the area Rx (protection member 10b). Similarly, from the position Peb on the X axis (the left wall surface 7b) to the search start position Psb, it is set as the adjustment area Rb. The above-mentioned search start position Psb is located closer to the area Rc (white reference sheet 10a) than the left end (position Py) of the area Ry.

As described above, the adjustment area Ra available for adjustment of the white reference data before adjustment is specified by the search start position Psa. The above search start position Psa is determined in advance in consideration of the thickness in the X-axis direction of both ends 10b' in the longitudinal direction, for example. In addition, the adjustment area Rb available for adjustment of the white reference data before adjustment is defined by the search start position Psb. The above search start position Psb is determined in advance in consideration of the thickness of the shield member 10b in the X-axis direction, for example. The flash memory of the banknote identification device 100 memorizes the above search start position Psa and search start position Psb.

Figure 6(a) shows the average order Iave. In this embodiment, among the pixels Gb located in the region Rc, the pixel Gb located at the search start position Psa, and four pixels Gb (five pixels Gb in total) arranged continuously from the pixel Gb on the region Rc side The order I will be sampled. In addition, the average value of the five levels I is calculated, and the calculation result is memorized as the average level Iave. In addition, the calculation method of the average level Iave is not limited to the above example. For example, it can also be set as a configuration in which the level I other than the five pixels Gb above the sample is calculated, and the average level Iave is calculated from the level I.

In addition, FIG. 6(a) shows the range from the average gradation Iave to the deviation threshold W (Iave-W≦I≦Iave+W). Hereinafter, in some cases, the range of the above gradation I is referred to as the "normal range". The deviation threshold value W of this embodiment is based on the fact that the order I of the pixel Gb facing the white reference sheet 10a among the pixels Gb in the adjustment area Ra becomes the normal range, and the order of the pixels Gb in the area Rx deviates from the normal range The method is decided in advance.

The banknote identification device 100 of this embodiment is a position (pixel Gb) on the X-axis after the specified gradation I has deviated from the normal range. Specifically, toward the direction of the white arrow shown in FIG. 6(a) (X-axis direction), from the level I of the search start position Psa, the difference between the level I and the average level Iave is sequentially determined Is the absolute value of (hereinafter referred to as "deviation width") greater than the deviation threshold W. In the specific example of FIG. 6(a), it is initially determined that the deviation width has exceeded the deviation threshold value W at the position Px.

Figure 6(b) is a schematic diagram illustrating a part of the adjusted white reference data. In the specific example of FIG. 6(b), a part of the white reference data located near the area Rx is displayed. Furthermore, in the specific example of FIG. 6(b), it is assumed that the deviation width exceeds the deviation threshold value W at the position Px in the same manner as the specific example of FIG. 6(a) described above. In the above case, as shown in FIG. 6(b), the level I of the region (region Rx) on the side of the position Pea (the right wall surface 7a) relative to the position Px is adjusted to the average level Iave.

Fig. 6(c) is a schematic diagram for explaining the overall white reference data after adjustment. In the specific example of FIG. 6(c), it is assumed that the deviation width has exceeded the deviation threshold value W at the position Px, similarly to the specific example of FIG. 6(b) described above. In the above case, the degree I of the region closer to the position Pea than the position Px is adjusted to the average degree Iave. Hereinafter, the average level Iave adjusted by the level I of the adjustment area Ra is described as "average level Iave1".

The banknote discriminating device 100 adjusts the level I of the adjustment area Rb in the same manner as the adjustment area Ra described above. Specifically, the banknote identification device 100 samples the pixel Gb located at the search start position Psa and the four pixels Gb (five pixels Gb in total) arranged continuously from the pixel Gb on the area Rc side. In addition, the average value of the five levels I is calculated, and the calculation result is memorized as the average level Iave2. Furthermore, it may also be a configuration in which the average gradation Iave2 is calculated from the gradation I other than the above five pixels Gb.

After that, the banknote discriminating device 100 moves from the search start position Psb to the position Peb, and determines whether the absolute value (deviation width) of the difference between the level I and the average level Iave2 of each position (pixel Gb) is greater than the deviation threshold W Big. In the specific example of FIG. 6(c), it is assumed that it has been initially determined that the deviation width has exceeded the deviation threshold value W at the position Py. In the above case, the banknote discriminating device 100 adjusts the gradation I from the position Py to the position Peb in the white reference data before adjustment to the average gradation Iave2.

After adjusting the gradation I of the adjustment area Ra and the adjustment area Rb, the banknote discriminating device 100 stores the white reference data in the white reference data storage unit 105. Based on the above white reference data, the image of banknotes taken near the side walls (7a, 7b) of the conveyance path 4 (adjustment area Ra, adjustment area Rb) can be appropriately shading corrected.

FIG. 7 is a flowchart of the pre-shipment adjustment processing performed by the banknote identification device 100. The above adjustment processing before shipment is performed in the manufacturing process (before shipment) of the banknote identification device 100. The paper money identification device 100 adjusts the pre-adjusted white reference data in the pre-shipment adjustment process, and stores the adjusted white reference data in the white reference data storage unit 105.

As described above, the banknote discriminating device 100 adjusts the white reference data before adjustment for both the adjustment area Ra (near the right wall 7a) and the adjustment area Rb (near the left wall 7b) in the area R where the bill passes Degree I. The banknote discriminating device 100 executes the pre-shipment adjustment process for the adjustment of the adjustment area Ra's degree I in the adjustment area Ra and the adjustment area Rb before performing the adjustment of the adjustment area Rb's degree I. Pre-adjustment processing. In the specific example of FIG. 7, it is assumed that the level I of the adjustment area Ra is adjusted during the adjustment process before shipment.

As shown in FIG. 7, when the pre-shipment adjustment process is started, the banknote discriminating device 100 obtains the level I of five pixels Gb from the pre-adjustment white reference data (S1). As described above, for example, in the case of adjusting the level I of the pixel Gb in the adjustment area Ra, the arrangement will be obtained from the search start position Psa which is the end of the left side (opposite to the right side wall) of the adjustment area Ra The level I of the five pixels Gb (that is, the pixels Gb arranged in the region Rc of FIG. 6(a)) in the left direction (the opposite direction of the X axis). The detection light after penetrating the white reference sheet 10a is incident on each of the above pixels Gb.

After obtaining the gradation I of the five pixels Gb from the pre-adjusted white reference data, the banknote discriminating device 100 calculates the average gradation Iave from the gradation I of the pixel Gb (S2). After that, the banknote identification device 100 identifies the target pixel Gb from each pixel Gb (S3). In the first step S3, the pixel Gb located at the above-mentioned search start position Psa is specified as the target pixel Gb. In addition, in the next step S3, the pixel to the right of the pixel Gb specified in the previous step S3 (on the side of a right side wall 7a) is specified as the target pixel Gb.

After the target pixel Gb has been specified, the banknote identification device 100 calculates the deviation width with respect to the level I of the target pixel Gb. Specifically, the banknote discrimination device 100 subtracts the average gradation Iave calculated in the above step S2 from the gradation I of the target pixel Gb, and stores the absolute value of the subtraction result as the deviation width of the target pixel Gb.

After the deviation width has been calculated for the target pixel Gb, the banknote discriminating device 100 determines whether the deviation width is larger than the deviation threshold value W (S5). When it has been determined that the deviation width is smaller than the deviation threshold value W (S5: No), the banknote discriminating device 100 returns the process to the above-mentioned step S3. After that, the banknote discrimination device 100 repeatedly executes steps S4 and S5 while changing the target pixel Gb in step S3. In the above configuration, the target pixels Gb are shifted one by one toward the side wall direction of the conveyance path 4, and it is repeatedly determined whether the deviation width of each pixel Gb is larger than the deviation threshold value W.

When it has been determined that the deviation width of the target pixel Gb is greater than the deviation threshold value W (S5: Yes), the banknote discriminating device 100 is configured for each pixel from the target pixel Gb to the side wall of the conveying path 4 The white reference data is adjusted to the average gradation Iave (S6). For example, when adjusting the white reference data of the adjustment area Ra near the right wall surface 7a, the white reference data of each pixel Gb from the target pixel Gb to the right wall surface 7a is adjusted to the average gradation Iave. After adjusting the white reference data, the banknote discriminating device H system ends the pre-shipment adjustment processing.

[Second Embodiment] The second embodiment of the present invention will be described below. In addition, regarding the elements whose functions or functions are equivalent to those of the first embodiment in each of the following exemplified embodiments, the symbols referred to in the description of the first embodiment are used, and detailed descriptions of each are appropriately omitted.

Fig. 8(a) is a cross-sectional view of the banknote discriminating device H in the second embodiment. Fig. 8(a) is a B-B cross-sectional view corresponding to Fig. 1(a) of the above-mentioned first embodiment. However, in FIG. 8(a), the first image sensor 6a, the second image sensor 6b, the lower cover 7 and the upper tray 8 among the various components of the banknote identification device 100 are selected and displayed. In addition, in FIG. 8(a), the optical path of the detection light irradiated from the light-emitting element Ga is shown with a dotted arrow.

As shown in FIG. 8(a), a guide portion 8L and a guide portion 8R are provided on the upper retainer 8 system. The guide portion 8R is substantially plate-shaped, and is erected along the right side wall (7a) of the conveyance path 4. As shown in 8(a), the lower end of the guide portion 8R is located closer to the bottom surface of the conveying path 4 than the contact surface of the upper support plate 8 and the lower cover 7 (S shown in Fig. 8(a)) side. The lower end of the above-mentioned guide portion 8R abuts on the vicinity of the right end of the banknotes placed on the bottom surface of the conveying path 4 and restricts the banknotes from moving in the upper direction (Z-axis direction).

The guide part 8L is substantially plate-shaped like the guide part 8L, and is erected along the left side wall (7b) of the conveyance path 4. Also, as shown in 8(a), the lower end of the guide portion 8L is located closer to the bottom surface of the conveying path 4 than the contact surface S of the upper receiving plate 8 and the lower cover 7, and is in contact with the placed The banknotes on the bottom surface of the conveying path 4 abut against the left end of the banknotes to restrict the banknotes from moving upward.

Assume a comparative example in which the guide 8 (R, L) is not provided. In the above comparative example, there are cases where the left or right end of the banknote will move to the aforementioned abutting surface S (floating occurs). In the above situation, the end of the banknote will penetrate between the upper support plate 8 and the lower cover 7, causing the banknote to be unable to move in the conveyance path 4, and there is a defect that the possibility of banknote clogging cannot be completely eliminated. According to the guide portion 8 (R, L) of the second embodiment, as described above, since the floating of the left and right ends of the banknote can be suppressed, there is an advantage that the above-mentioned defects can be suppressed.

The guide portion 8 (R, L) of the second embodiment is provided in an area R (refer to the above-mentioned FIG. 5(a)) that can be used for image capturing for identification of banknotes. In the above-mentioned structure, compared with the structure in which the guide part 8 (R, L) is provided on the outer side of the area|region R, for example, there exists an advantage that the banknote identification device H can be easily reduced in size.

However, the components located between the light-emitting element Ga of the first image sensor 6a and the pixel Gb of the second image sensor 6b need to transmit light. Considering the above situation, similar to the upper receiving plate 8, the guide portions 8 (R, L) are formed of a light-transmitting member (for example, a transparent resin).

However, in the case where the transparent guide portion 8 (R, L) has been provided in the region R, a new problem of the detection light being refracted by the guide portion 8 (R, L) may occur. That is, with the guide portion 8 (R, L), the problem of the optical path of the detection light deviating from the original optical path may occur. In addition, when the above problems have occurred, there may be a defect that the white reference data used for the shading correction of the image data cannot be properly generated.

For example, the detection light irradiated from the light emitting element Ga located directly above the guide portion 8R should originally be incident on the pixel Gb located directly below the guide portion 8R. However, for example, as shown in FIG. 8(a), when the detection light irradiated from the light-emitting element Ga has been refracted by the guide portion 8R, the detection light may be incident on the pixel Gb that should be incident. It is another pixel Gb (for example, an adjacent pixel Gb). In the above case, the level I of the white reference data (the white reference data before adjustment) in the pixel Gb where the detection light should be incident is higher than the original level (without the guide 8R) I'm still small. On the other hand, the gradation I of the white reference data in the other pixel Gb is larger than the original gradation I.

Fig. 8(b) is a schematic diagram for explaining the white reference data before adjustment in the second embodiment. FIG. 8(b) shows the level I of the detection light that has been incident on the second image sensor 6b in each position on the X axis of the area R (the area between the side walls of the conveying path 4).

Furthermore, in the above-mentioned first embodiment, the white reference data is generated by irradiating the detection light on the white reference member 10 (refer to FIG. 3). In the second embodiment, when the white reference material is generated, the white reference member 10 is not placed on the conveyance path 4 (area R). In the above second embodiment, it is not necessary to place the white reference member 10 on the conveyance path 4 when generating the white reference data, so during the period after the manufacturing process of the banknote identification device H (during market operation) , Can generate white reference data on a regular basis. For example, it is possible to generate white reference data every time the power supply of the banknote checking device H is input.

The level I of the detection light irradiated from the light-emitting element Ga, when it has penetrated the white reference paper (for example, the above-mentioned white reference sheet 10a), will become an approximation of the situation that does not penetrate the white reference paper. 1/10. Considering the above situation, in the second embodiment, the white reference data whose gradation of each pixel Gb becomes 1/10 is stored in the white reference data storage section 105.

As shown in FIG. 8(b), in the second embodiment, the position on the X axis of the right side wall surface 7a (the right end of the region R) of the conveying path 4 is described as "position Pea". In addition, the position on the X axis of the left side wall surface 7b (the left end of the region R) of the conveyance path 4 is described as "position Peb".

In the second embodiment, the pre-correction white reference data of the pixels Gb in the adjustment area Ra near the right side wall and the adjustment area Rb near the left side wall of the conveyance path 4 are adjusted in the same manner as in the first embodiment described above. Specifically, for a pixel Gb whose absolute value (deviation width) of the difference between the average gradation Iave and the gradation I is larger than the deviation threshold W, the gradation I of the pixel Gb is adjusted to the average gradation Iave.

In the specific example of FIG. 8(b), when viewed from the center of the region R toward the position Pea (the right side wall), the deviation width of the pixel Gb at the position Px will initially be greater than the deviation threshold W It's still big. In the above specific example, the pre-adjusted white reference data from the position Px to the position Pea is adjusted to the average gradation Iave. Similarly, when viewed from the center of the region R toward the position Peb (left side wall), the deviation width of the pixel Gb at the position Py becomes larger than the deviation threshold value W at first. In the above specific example, the pre-adjusted white reference data from the position Py to the position Peb is adjusted to the average gradation Iave.

Fig. 8(c) is a schematic diagram for explaining the adjustment area Ra in the second embodiment. Fig. 8(c) shows the white reference data before adjustment in the same manner as in Fig. 8(b) described above. However, in the specific example of FIG. 8(c), a part of the pre-adjustment white reference data including the adjustment area Ra is displayed.

As shown in FIG. 8(c), the adjustment area Ra refers to an area determined in advance from the position Psa to the position Pea (right side wall), similarly to the above-mentioned first embodiment. The above position Psa is set in advance in consideration of the shape and refractive index of the guide portion 8R (the range affected by the refraction of the detected light). Similarly, the adjustment area Rb refers to an area determined in advance from the position Psb to the position Peb (left side wall) as in the above-mentioned first embodiment. The above position Psb is set in advance in consideration of the shape and refractive index of the guide portion 8L.

FIG. 8(d) is a schematic diagram showing the white reference data after the gradation I of the adjustment area Ra has been adjusted in the specific example of FIG. 8(c) described above. In the specific example of FIG. 8(d), it is assumed that the level I from the position Px to the position Pea has been adjusted to the average level Iave. Furthermore, the level I of the adjustment area Rb is adjusted by the same method as the adjustment area Ra. The banknote discriminating device H forms the gradation I of all areas of the pre-adjusted white reference data after the gradation I of the adjustment area Ra and the adjustment area Rb has been adjusted to 1/10 times, and memorizes it as the white reference data.

Even in the above-mentioned second embodiment, the same effect as the above-mentioned first embodiment can be achieved. In addition, the positions where the guides (8R, 8L) are provided can be changed as appropriate. For example, it can also be set as the structure which provided the guide part on the upper surface 7d of the lower cover 7. In addition, in the second embodiment, although the guide portion is provided near the side wall of the conveying path 4, it may be provided near the center of the conveying path 4. In the above case, the area including the guide portion that has been set near the center is set as the adjustment area, and the white reference data of the pixels Gb located in the adjustment area can be adjusted.

[Third Embodiment] In the first embodiment described above, the pre-adjustment white reference data obtained in the state where the white reference member 10 (see FIG. 3(a)) has been placed in the area R of the conveyance path 4 is used to determine the The white reference data actually used in shading correction. Also, in the second embodiment, the white reference member 10 is obtained from the state where the white reference member 10 is not placed in the area R of the conveyance path 4 (obtained by directly irradiating the detection light from the light-emitting element Ga toward the pixel Gb ) Adjust the pre-white reference data to determine the white reference data.

Hereinafter, for the sake of explanation, there are cases where the pre-adjustment white reference data obtained in the state where the white reference member 10 has been placed is described as the "first pre-adjustment data". In addition, there is a case where the pre-adjustment white reference data obtained in a state where the white reference member 10 is not placed is described as the "second pre-adjustment data". Although the details will be described later, in the third embodiment, both the first pre-adjustment data and the second pre-adjustment data are used to determine the white reference data D (refer to FIG. 9(c) described later).

9(a) to 9(c) are schematic diagrams for explaining the third embodiment. The banknote discriminating device 100 of the third embodiment is similar to the above-mentioned first embodiment, and includes a region R (including Rx and Ry) through which banknotes pass. As described above, in the area R, the area Rx refers to the area near the right side wall 7a. In the region R, the region Ry refers to the region near the left wall surface 7b. Hereinafter, for the sake of description, the area R other than the area Rx and the area Ry is referred to as "area Rz". The above area Rz refers to the area including the center of the area R.

In the banknote identification device 100 of the third embodiment, N pixels G are provided. Specifically, from the left side wall 7b to the right side wall 7a, in the order of the pixel G1, the pixel G2, ..., the pixel GN, a row of N pixels G are arranged. For example, among the N pixels G, n pixels G from the pixel G1 to the pixel Gn are arranged in the region Ry. In addition, the N-2n pixels G from the pixel G(n+1) to the pixel G(Nn) are arranged in the area Rz, and the n pixels G from the pixel G(N-n+1) to the pixel GN are arranged in the area Rx . Furthermore, in the third embodiment, when viewed from the left wall surface 7b, there is a case where the i-th pixel G is described as "pixel Gi" (1≦i≦N).

Figure 9(a) is a schematic diagram illustrating the first pre-adjustment data. The first pre-adjustment data is substantially the same as the pre-adjusted white reference data shown in Fig. 5(b) of the above-mentioned first embodiment.

Specifically, in the region R, the pixel G(n+1) to the pixel G(N-n) in the region Rz are opposed to the white reference sheet 10a of the white reference member 10. Therefore, the gradation of the first pre-adjustment data for each pixel G in the region Rz (in some cases described below as “gradation Ia”) can be adopted as the white reference data. On the other hand, in the region R, the pixels G1 to Gn in the region Ry are opposed to the protection member 10b of the white reference member 10. Therefore, the gradation Ia in the region Ry is inappropriate as the white reference data. The gradation Ia in the region Rx in the relevant region R is also inappropriate as the white reference data in the same way as the gradation Ia in the region Ry.

Figure 9(b) is a schematic diagram illustrating the second pre-adjustment data. The second pre-adjustment data is substantially the same as the pre-adjusted white reference data shown in FIG. 8(b) of the second embodiment described above. However, in the third embodiment, even if the detection light stronger than the predetermined level (hereinafter referred to as the "upper limit level Im") is irradiated toward the pixel G, the second adjustment data of the pixel G will still be It becomes the upper limit level Im.

As shown in FIG. 9(b), the second pre-adjustment data in the area Rz in the area R becomes the upper limit level Im. On the other hand, in the area Rx and the area Ry in the area R, as described above, the detection light is refracted by the guide portion 8 (R, L). Therefore, the level of the second pre-adjustment data of each pixel G in the region Rx and the region Ry (in some cases described below is described as "level Ib") is as shown in FIG. 9(b), and some cases are not Will become the upper limit level Im.

In the above configuration, when the actual detected light level is stronger than the upper limit level Im, the second pre-adjustment data in the region Rz is different from the actual detected light level. On the other hand, the first pre-adjustment data in the region Rz represents the actual level of the detected light. Therefore, the gradation of each pixel G in the region Rz is preferably corrected by the white reference data obtained from the first pre-adjustment data, compared to the white reference data obtained from the second pre-adjustment data.

In addition, as described above, the first pre-adjustment data in the region Rx and the region Ry are inappropriate as the white reference data. Therefore, the gradation of each pixel G in the area Rx and the area Ry is preferably corrected by the white reference data obtained from the second pre-adjustment data, compared to the white reference data obtained from the second pre-adjustment data. To correct. Furthermore, by correcting the gradation of each pixel G in the area Rx and the area Ry with the white reference data obtained from the second pre-adjustment data, the gradation of the pixel G that does not face the banknote is corrected to the upper limit gradation Im , Or the gradation of the pixel G that does not face the banknote is corrected to be less than the upper limit gradation Im. Therefore, the outer edge of the banknote has the advantage of being easy to detect.

Considering the above situation, the white reference data of the third embodiment adopts the following structure: the white reference data of the gradation of each pixel G of the correction area Rz is determined by the first pre-adjustment data, and the correction area Rx and the area The white reference data of the gradation of each pixel G of Ry is determined by the second pre-adjustment data.

Fig. 9(c) is a conceptual diagram of the white reference data D in the third embodiment. The white reference data D is composed of N correction values d. Each correction value d corresponds to any one of each pixel G. Hereinafter, the correction value d corresponding to the pixel Gi is referred to as "correction value di". When the gradation of the pixel Gi before correction is set to the measured gradation Ivi (1≦i≦N), the gradation of the pixel Gi after shading correction (hereinafter referred to as "correction gradation Ici") can be borrowed It is obtained by multiplying the measured order Ivi by the correction value di (Ici=Ivi×di).

Each of the above correction values d includes: the correction value d determined by the first pre-adjustment data (refer to Fig. 9(a)); and the correction value determined by the second pre-adjustment data (refer to Fig. 9(b)) Value d. The above configuration, in other words, the white reference data D is composed of a correction value d (first correction value) and a correction value d (second correction value). The correction value d (first correction value) The reference member 10 is obtained by irradiating the detection light, and the correction value d (second correction value) is obtained by irradiating the detection light that has not penetrated the white reference member 10 to the pixel G (light receiving means).

For example, in the second pre-adjustment data, the correction value d1 is determined from the gradation Ia1 of the pixel G1 in the region Ry. Similarly, in the second pre-adjustment data, each level Ia (Ia2 to Ian) from the pixel G2 to the pixel Gn in the region Ry determines the correction value d2 to the correction value dn. Furthermore, in the second pre-adjustment data, the correction value d(N-n+1) is determined from the level Ia(N-n+1) of the pixel G(N-n+1) in the region Rx. Similarly, in the second pre-adjustment data, each level Ia (Ia(N-n+2) to IaN) from the pixel G(N-n+2) of the region Rx to the pixel GN is used to determine the correction value d( N-n+2) to the correction value dN.

As understood from the above description, the correction value d corresponding to each pixel G of the region Rx and the region Ry is determined by the second pre-adjustment data. Specifically, the correction value di corresponding to each pixel G in the region Rx and the region Ry (in the case of 1≦i≦n, Nn≦i≦N) is obtained by dividing the upper limit level Im by the second pre-adjustment data The order is obtained by Ibi (di=Im/Ibi).

On the other hand, the correction value d corresponding to each pixel G in the region Rz is determined by the first data before adjustment. Specifically, in the first data before adjustment, the correction value d(n+1) is determined from the level Ia(n+1) of the pixel G(n+1) in the region Rz. Similarly, in the first pre-adjustment data, each level Ia (Ia(n+2) to Ia(Nn)) from pixel G(n+2) to pixel G(Nn) in area Rz is used to determine the correction value d(n+2) to the corrected value d(Nn). Specifically, when the white gradation I is set to the white gradation Iw, the correction value di corresponding to each pixel G in the region Rz (in the case of n+1≦i≦Nn-1) can be determined by The white level Iw is divided by the level Iai of the data before the first adjustment (di=Iw/Iai).

Furthermore, the pixel G whose correction value d is determined from the first pre-adjustment data and the pixel G whose correction value d is determined from the second pre-adjustment data can be changed as appropriate. For example, it can also be set that the correction value of the pixel G in an area wider than the area Rz is determined by the first pre-adjustment data.

The paper discriminating device of the present invention is, for example, the following paper discriminating device.

The paper discriminating device (100) of the present invention is provided with: conveying means (conveyance control unit 101), which moves the paper along the conveying path (4); and light emitting means (light emitting element Ga), which is directed toward the moving paper One side irradiates the detection light; and the light receiving means (pixel Gb), which is arranged at a position opposite to the other side of the moving paper to receive the detection light passing through the paper, and along the moving direction of the paper ( The Y-axis direction) orthogonal to the width direction (X-axis direction, scanning axis direction) is arranged in a plurality of; and image data generation means (image data generation part 104), which is used to generate and have been incident on the light receiving means detection The image data of the gradation corresponding to the light; and the white reference data storage means (the white reference data storage section 105), which memorizes the white reference data, the white reference data is obtained by correcting the white reference member used for the shading correction of the image data (10) Obtained by irradiating the detection light; and movement restricting means (right side wall 7a, left side wall 7b), which are located at the end of the conveying path in the width direction and forming the side wall of the conveying path; and adjusting means (adjusting part 109 ), which is based on the condition that the position in the width direction of the light receiving means is within a predetermined specific area (adjustment area Ra, adjustment area Rb), and the white reference data used for shading correction of the image data of the light receiving means is adjusted to a predetermined Value (average degree Iave). According to the above structure, the image of the paper can be appropriately shading corrected.

As a preferred aspect of the present invention, the specific area means that the distance in the width direction to the movement restriction means is less than a predetermined distance (the distance from Psa to Pea in FIG. 5, or the distance from Psb to Peb) Area. In addition, as another preferred aspect of the present invention, it is provided with: abutting means (guide portion), which is provided between the light-emitting means and the light-receiving means, and abuts on one or the other side of the paper, and The light-transmitting member is formed, and the position in the width direction of the abutting means is located in a specific area.

1: Lower unit 2: Upper unit 3a: Insertion port 3b: Take the entrance 4: Transport path 5: Handling device 5a: Lower transport member (transportation part) 5b: Upper transport member 6: Sensor 6a: The first image sensor 6b: Second image sensor 6c: Magnetic sensor 7: Lower cover 7a: Right side wall 7b: left side wall 7c, 8a: recess 7d: upper surface 8: Upper bearing plate 8b: lower surface 8L, 8R: Guiding part 9, 9a, 9b: white reference film for reflection 10: White reference component 10a: White reference flake 10b: Protective member 10b’: Both ends in the longitudinal direction 100, H: Paper currency identification device 101: Transport Control Department 102: Sensor Department 103: Sensor control unit 104: Image data generation department 105: White reference data memory 106: Correction Department 107: White reference data generation department 108: Adjust the position determination part 109: Adjustment Department B: banknotes D: White reference data d,di: correction value G: pixel Ga: Light-emitting element Gb: pixel (object pixel) h: distance I, Ia, Ib: degree Iave, Iave1, Iave2: average order Ici: correction level Im: upper limit Iw: white degree K: opening L: Optical axis Pea, Peb, Px, Py: location Psa, Psb: Search start position R, Rc, Rx, Ry, Rz, r: area Ra, Rb: adjustment area S: abutting surface T: reflector W: Deviation from the threshold

[Fig. 1] is a perspective view and a cross-sectional view of the appearance of the banknote discriminating device of the first embodiment. [Figure 2] is an exploded perspective view and an enlarged cross-sectional view of the banknote identification device of the first embodiment. [Fig. 3] A schematic diagram for explaining the white reference member of the first embodiment. [Figure 4] is a functional block diagram of the banknote identification device of the first embodiment. [Fig. 5] A schematic diagram for explaining the white reference data before adjustment of the first embodiment. Fig. 6 is a schematic diagram for explaining the method of adjusting the white reference data of the first embodiment. [Fig. 7] is a flowchart (flowchart) of the pre-shipment adjustment processing of the first embodiment. Fig. 8 is a schematic diagram for explaining the method of adjusting the white reference data of the second embodiment. [Fig. 9] is a schematic diagram for explaining the white reference data of the third embodiment.

I: Degree

Iave, Iave1, Iave2: average order

Pea, Peb, Px, Py: location

Psa, Psb: Search start position

Ra, Rb: adjustment area

Rc, Rx: area

W: Deviation from the threshold

Claims (6)

A paper discriminating device, which is characterized by comprising: a conveying means for moving the paper along a conveying path; and a light emitting means for irradiating a detection light toward one of the moving paper surfaces; and a light receiving means, which is arranged at The position opposite to the other side of the moving paper is used to receive the detecting light from the paper, and a plurality of them are arranged along the width direction orthogonal to the moving direction of the paper; and image data generating means, It is used to generate image data corresponding to the level of the detection light that has been incident on the light receiving means; and the white reference data memory means, which memorizes white reference data, the white reference data is corrected by shading The white reference member used in the aforementioned image data is obtained by irradiating the aforementioned detection light; and a movement restricting means, which is located at the end of the aforementioned conveying path in the width direction and forming the side wall of the conveying path; and abutting means, the aforementioned width The position in the direction is in a specific area determined in advance, is set between the light emitting means and the light receiving means, abuts on one side or the other side of the paper, and is formed by a light-transmitting member; and The adjusting means adjusts the white reference data used for shading correction of the image data of the light receiving means to a predetermined value based on the condition that the widthwise position of the light receiving means is within the predetermined area determined in advance. The paper discriminating device of claim 1, wherein the specific area is an area where the distance in the width direction to the movement restricting means is less than a predetermined distance. A method for adjusting white reference data is a method for adjusting the white reference data used in the shading correction of the aforementioned image data in a paper discriminating device, the paper discriminating device is provided with: a conveying means that moves the paper along a conveying path; and The light-emitting means irradiates the detection light toward one side of the moving paper; and the light-receiving means is arranged at a position opposite to the other side of the moving paper to receive the detection light from passing through the paper Light, and a plurality of pieces are arranged along the width direction orthogonal to the moving direction of the paper; and image data generating means for generating image data of the level corresponding to the detection light that has been incident on the light receiving means ; And movement restriction means, which are located at the widthwise end of the aforementioned conveying path and form the side walls of the conveying path; and abutting means, whose position in the aforementioned width direction is within a specific area determined in advance, is set Between the light-emitting means and the light-receiving means, and abut on one or the other surface of the paper, and are formed by a light-transmitting member; A step of adjusting the aforementioned white reference data used for shading correction of the image data of the light-receiving means to a predetermined value in the determined specific area as a condition. A program that is used to make a computer adjust the white reference data used for shading correction of the aforementioned image data in the paper discriminating device. The sheet moves along the conveying path; and a light emitting means, which irradiates detection light toward one side of the moving paper; and a light receiving means, which is arranged at a position opposite to the other side of the moving paper, for receiving the passing The detection light from the paper, and a plurality of them are arranged along the width direction orthogonal to the moving direction of the paper; and the image data generating means, which is used to generate the detection light that has been incident on the light receiving means Image data of the corresponding gradation; and movement restriction means, which are located at the end of the conveying path in the width direction and forming the side wall of the conveying path; and abutting means, the position of which in the width direction is determined in advance The specific area is set between the light-emitting means and the light-receiving means, and abuts on one or the other side of the paper, and is formed by a light-transmitting member; its characteristic is that the computer is used as an adjustment means The adjusting means adjusts the white reference data used for shading correction of the image data of the light receiving means to a predetermined value based on the condition that the widthwise position of the light receiving means is within a predetermined area determined in advance. A paper discriminating device, which is characterized by comprising: a conveying means for moving the paper along a conveying path; and a light emitting means for irradiating a detection light toward one of the moving paper surfaces; and a light receiving means, which is arranged at The position opposite to the other side of the moving paper is used to receive the detecting light from the paper, and a plurality of them are arranged along the width direction orthogonal to the moving direction of the paper; and Image data generating means, which is used to generate image data corresponding to the gradation of the detection light that has been incident on the light receiving means; and white reference data memory means, which memorize the white used for shading correction of the image data Reference data; the aforementioned white reference data is composed of a first correction value and a second correction value, the first correction value is obtained by irradiating the aforementioned detection light on the white reference member, and the second correction value is obtained by It is obtained by irradiating the detection light that has not penetrated the white reference member to the light receiving means; and is further provided with a correction part, and the correction part sets the position in the width direction to be outside the predetermined specific area. The image data of the light-receiving means uses the first correction value to perform shading correction, and the position in the width direction is within the predetermined area determined in advance for the image data of the light-receiving means, and the second correction value is used Perform shading correction. A correction method is a correction method for shadow correction of image data. The paper discriminating device is provided with: a conveying means for moving the paper along a conveying path; and a light emitting means for illuminating the detecting surface toward one of the moving papers. Metering; and light receiving means, which is arranged at a position opposite to the other side of the moving paper, used to receive the detection light from the paper, and along the width direction orthogonal to the moving direction of the paper Is equipped with a plurality of; and image data generating means, which is used to generate and have been incident on the aforementioned receiving The light means the image data corresponding to the level of the detected light; and the white reference data memory means, which memorizes the white reference data used for the shading correction of the image data; the white reference data includes the first correction value and The second correction value is formed by irradiating the detection light on the white reference member, and the second correction value is obtained by irradiating the detection light that does not penetrate the white reference member Obtained by the aforementioned light-receiving means; equipped with a correction step, the aforementioned correction step is to use the aforementioned first correction value to perform shading on the aforementioned image data of the aforementioned light-receiving means whose position in the width direction is outside a predetermined specific area Correcting, and using the second correction value to perform shading correction on the image data of the light receiving means whose position in the width direction is in the predetermined specific area determined in advance.

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