WO2022176210A1

WO2022176210A1 - Adjustment value calculation method and paper product discrimination unit

Info

Publication number: WO2022176210A1
Application number: PCT/JP2021/006700
Authority: WO
Inventors: 勝巳大治
Original assignee: 富士通フロンテック株式会社
Priority date: 2021-02-22
Filing date: 2021-02-22
Publication date: 2022-08-25
Also published as: JP7418653B2; JPWO2022176210A1

Abstract

The present invention involves: creating a first image sensor unit having a first image pickup device that produces an output adjusted by using a first medium having a uniform reflectance density and transmission density over the entire surface thereof; setting a target value on the basis of a first output value, which is a value output by the first image pickup device when the first image sensor unit images a second medium, the second medium being any medium different from the first medium; acquiring a second output value, which is a value output by a second image pickup device when a second image sensor unit having the second image pickup device images the second medium; and calculating an adjustment value, which is used for adjusting the output of the second image pickup device when the second image sensor unit images paper products, on the basis of the second output value and the target value.

Description

Adjustment value calculation method and paper sheet discrimination unit

The present disclosure relates to an adjustment value calculation method and a paper sheet discrimination unit.

A banknote handling device used in an automatic teller machine (ATM) or the like has a banknote discrimination unit that discriminates banknotes. The banknote discrimination unit has, for example, a transport mechanism that transports banknotes, and a plurality of types of discrimination sensor units that are used to discriminate banknotes transported by the transport mechanism. For example, an image sensor unit that captures an image of a banknote, an ultraviolet sensor unit that detects a fluorescent component of the banknote, and a magnetic sensor unit that detects a magnetic component of the banknote are used as the multiple types of discrimination sensor units.

JP-A-05-191561

The image sensor unit has multiple image sensors, and the output (sensitivity) of each image sensor varies. Therefore, adjustment to uniform the output of multiple image sensors (hereafter referred to as "output adjustment") ) is performed. In addition, image sensor units of the same model are mounted in a plurality of banknote validator units of the same model. However, even among image sensor units of the same model, there are variations in output between individual image sensor units, so output adjustment is performed even among a plurality of image sensor units of the same model.

Output adjustment is performed using a medium with uniform reflection and transmission densities over the entire surface (hereinafter sometimes referred to as "high-precision medium"). are adjusted so that the outputs of all image sensors are uniform at a constant target value.

In this way, output adjustment uses a high-precision medium whose reflection density and transmission density are strictly controlled. Also, in order to adjust the output of a large number of image sensor units of the same model, it is necessary to create a large number of high-precision media with small errors between multiple media (hereafter referred to as "media error"). be. Therefore, the high-precision medium used for output adjustment is expensive, and the cost required for output adjustment is high.

Therefore, the present disclosure proposes a technology capable of reducing the cost required for adjusting the output of the image sensor unit.

In the adjustment value calculation method of the present disclosure, first, a first image sensor unit having a first imaging element whose output is adjusted is created using a first medium, which is a medium whose reflection density and transmission density are uniform over the entire surface. do. Next, a target value is set based on a first output value that is an output value of the first imaging device when a second medium, which is an arbitrary medium different from the first medium, is imaged by the first image sensor unit. do. Next, a second output value, which is the output value of the second image pickup device when the second medium is imaged by a second image sensor unit having the second image pickup device, is obtained. Then, an adjustment value used for adjustment of the output of the second imaging element when the second image sensor unit images the sheet is calculated based on the second output value and the target value.

According to the disclosed technique, the cost required for output adjustment of the image sensor unit can be reduced.

FIG. 1 is a diagram illustrating a configuration example of a banknote handling device according to Example 1 of the present disclosure. FIG. 2 is a diagram illustrating a configuration example of a banknote discrimination unit according to the first embodiment of the present disclosure; FIG. 3 is a diagram illustrating a configuration example of a banknote validating unit according to the first embodiment of the present disclosure; FIG. 4 is a diagram illustrating a configuration example of a banknote discrimination unit according to the first embodiment of the present disclosure; 5A is a diagram illustrating a configuration example of an image sensor unit according to Example 1 of the present disclosure; FIG. 5B is a diagram illustrating a configuration example of an image sensor unit according to the first embodiment of the present disclosure; FIG. FIG. 6 is a diagram illustrating a mounting example of the image sensor unit according to the first embodiment of the present disclosure. FIG. 7 is a flowchart illustrating an example of a processing procedure in the output adjustment value calculation method according to the first embodiment of the present disclosure. FIG. 8 is a diagram for explaining an example of a method of calculating an output adjustment value according to the first embodiment of the present disclosure; FIG. 9 is a diagram for explaining an example of a method of calculating an output adjustment value according to the first embodiment of the present disclosure; FIG. 10 is a diagram for explaining an example of a method of calculating an output adjustment value according to the first embodiment of the present disclosure; FIG. 11 is a diagram for explaining an example of a method of calculating an output adjustment value according to the first embodiment of the present disclosure; FIG. 12 is a diagram for explaining an example of a method for setting target unit target values according to the second embodiment of the present disclosure. FIG. 13 is a diagram for explaining an example of a method for setting target unit target values according to the second embodiment of the present disclosure.

Hereinafter, embodiments of the present disclosure will be described based on the drawings. In the following embodiments, the same reference numerals are given to the steps in which the same configuration and the same processing are performed.

[Example 1]
<Configuration of banknote handling device>
FIG. 1 is a diagram illustrating a configuration example of a banknote handling device according to Example 1 of the present disclosure. In FIG. 1, the banknote handling apparatus 1 includes a banknote depositing/dispensing unit 6 for depositing/dispensing banknotes 3, a banknote discrimination unit 7 for discriminating the banknotes 3 deposited in the banknotes 3, and a banknote transported from the banknote discrimination unit 7. 3, and a plurality of holding portions 8 for temporarily storing . The banknote handling apparatus 1 also includes a storage unit 9 for storing the banknotes 3 sent from the storage units 8 , a replenishment unit 10 for supplementing the banknotes 3 to be withdrawn, and banknotes not returned to the deposit/withdrawal unit 6 . 3 and a transport mechanism 12 for transporting the banknotes 3 . In the embodiments, paper money 3 is taken as an example of paper sheets, but the paper sheets to which the disclosed technology can be applied are not limited to paper money 3, and the disclosed technology can also be applied to other paper sheets such as cash vouchers. It is possible.

<Configuration of banknote validating unit>
2, 3, and 4 are diagrams showing configuration examples of the banknote validating unit according to the first embodiment of the present disclosure. FIG. 2 shows a perspective view of the banknote validating unit 7, and FIGS. 3 and 4 show side views of the banknote validating unit 7. As shown in FIG. 3 shows the case where the banknote validating unit 7 is closed, and FIG. 4 shows the case where the banknote validating unit 7 is open.

As shown in FIGS. 1 and 2, the banknote validating unit 7 has, as part of the transport mechanism 12, a pair of upper and lower transport path forming bodies 15 forming a transport path 14 for the banknotes 3. A transport path forming body 15 on the upper side of the path forming body 15 is provided so as to be splittable on a dividing plane B along the transport direction A of the banknotes 3 .

The conveying path structure 15 includes a plurality of conveying rollers 17 that convey the banknotes 3, a chassis 18 that rotatably supports the plurality of conveying rollers 17, and a drive mechanism (not shown) that drives the plurality of conveying rollers 17. have With respect to the chassis 18 of the lower transport path structure 15, the chassis 18 of the upper transport path structure 15 is supported via a rotating shaft 19 so as to be rotatable in the C direction. A plurality of transport rollers 17 are arranged along the transport path 14 and transport the rectangular banknotes 3 in a state in which the short sides of the banknotes 3 are parallel to the transport direction A. As shown in FIG.

As shown in FIGS. 2, 3, and 4, the banknote validating unit 7 includes a pair of upper and lower image sensor units 21 that capture and image the banknotes 3, and each image sensor unit 21 is detachable. It has a pair of upper and lower first mounting parts 26 mounted on. Of the two image sensor units 21 , one image sensor unit 21 images one side of the bill 3 , and the other image sensor unit 21 images the other side of the bill 3 .

The banknote discrimination unit 7 also has an ultraviolet/magnetic sensor unit 22 having an ultraviolet sensor and a magnetic sensor, and a second mounting portion 27 to which the ultraviolet/magnetic sensor unit 22 is detachably mounted.

The banknote validating unit 7 also includes an entrance sensor 24a for detecting the position of the banknote 3 entering the banknote validating unit 7, a leaving sensor 24b for detecting the position of the banknote 3 leaving the banknote validating unit 7, and a banknote 3 thickness and a thickness sensor 25 for detecting the

As shown in FIGS. 2, 3 and 4, the entry sensor 24a is arranged on the entry side of the bill 3 in the conveying direction A. a light receiving portion that receives light emitted from the portion; Similarly, the exit sensor 24b is arranged on the exit side of the paper money 3 in the transport direction A, and includes a light emitting part that emits light toward the transport path 14 and a light receiving part that receives the light emitted from the light emitting part. have The entrance sensor 24a and the exit sensor 24b detect the position of the banknote 3 (passage of the banknote 3) by blocking the light emitted from the light emitting portion of the banknote 3 transported along the transport path 14. FIG.

The thickness sensor 25 is arranged between the image sensor unit 21 and the ultraviolet/magnetic sensor unit 22 in the transport direction A, and detects the thickness of the banknotes 3 being transported.

<Configuration of image sensor unit>
5A and 5B are diagrams illustrating a configuration example of an image sensor unit according to Example 1 of the present disclosure. 5A shows a side view of the image sensor unit 21, and FIG. 5B shows a front view of the image sensor unit 21. As shown in FIG.

The image sensor unit 21 includes a light source 30, a plurality of imaging elements 31, and an adjustment value (hereinafter referred to as an "output adjustment value") used to adjust the output of the imaging element 31 (hereinafter sometimes referred to as "element output"). ), and a circuit board 33 on which a plurality of imaging elements 31 and the memory 32 are provided. In the image sensor unit 21, a plurality of first to X-th imaging elements 31 are arranged in a line along a straight line orthogonal to the conveying direction A of the banknotes 3. As shown in FIG. The number of imaging elements included in the image sensor unit 21 is, for example, 1632 (X=1632).

As shown in FIG. 5B, the light source 30 is provided in a line along the arrangement direction D of the plurality of imaging elements 31. As shown in FIG. It is placed on both sides of the sandwich. Further, inside the image sensor unit 21, a linear lens is provided at a position facing the plurality of image pickup elements 31 along the array direction D of the plurality of image pickup elements 31 (that is, the main scanning direction of the image sensor unit 21). A member 35 is provided. The light source 30 and the lens member 35 are covered with a cover member 36 having optical transparency.

Also, the circuit board 33 is provided with a connector 38 electrically connected to the banknote discrimination unit 7 and an integrated circuit 37 . Examples of the integrated circuit 37 include ASIC (Application Specific Integrated Circuit), PLD (Programmable Logic Device), FPGA (Field-Programmable Gate Array), and the like.

FIG. 6 is a diagram showing a mounting example of the image sensor unit according to the first embodiment of the present disclosure. As shown in FIGS. 3, 4 and 6, each of the pair of upper and lower first mounting portions 26 is arranged to face the upper transport path forming body 15 and the lower transport path forming body 15, respectively. It is arranged and provided in an open state on the dividing surface B of the transport path 14 . As a result, the first mounting portion 26 can be easily accessed by opening the dividing surface B of the pair of upper and lower transport path forming bodies 15 . As shown in FIG. 6 , one end of a connection cable 41 electrically connected to the banknote validating unit 7 is provided in the first mounting portion 26 , and a connection terminal 42 of the connection cable 41 is connected to the circuit board 33 . is connected to the connector 38 of the

<How to calculate the output adjustment value>
FIG. 7 is a flowchart illustrating an example of a processing procedure in the output adjustment value calculation method according to the first embodiment of the present disclosure. 8 to 11 are diagrams for explaining an example of a method of calculating an output adjustment value according to the first embodiment of the present disclosure. The processing of steps S105 to S120 in FIG. 7 is performed by connecting the image sensor unit 21 to an output adjustment device (not shown), and a processor included in the output adjustment device (hereinafter referred to as an “output adjustment processor”). (sometimes called). A computer is an example of an output adjusting device.

In step S105 of FIG. 7, an image sensor unit (hereinafter sometimes referred to as a "master unit") that serves as a reference for output adjustment is created. The configuration of the master unit is the same as that of the image sensor unit 21 .

In step S105, first, under the control of the output adjustment processor, the image sensor unit 21 picks up an image of the high-precision medium. As shown in FIG. An output value OP11 of each of the plurality of image sensors 31 is acquired. Below, each output value of the plurality of imaging elements 31 may be referred to as "element output value".

Next, in order to adjust the element output values OP11 among the plurality of image pickup elements 31 so as to be uniform at a constant target value TG1, the output adjustment processor, as shown in FIG. A first output adjustment value AJ1 represented by (1) is calculated, and the calculated first output adjustment value AJ1 is stored in the memory 32 .
AJ1=TG1/OP11 (1)

The image sensor unit 21 in which the first output adjustment value AJ1 for each imaging element 31 is stored in the memory 32 becomes the master unit. After the first output adjustment value AJ1 is stored in the memory 32, the integrated circuit 37 multiplies the element output value of each imaging element 31 by the first output adjustment value AJ1 to adjust the output of the master unit. That is, by storing the first adjustment value AJ1 in the memory 32, a master unit having the image pickup device 31 whose device output is adjusted using a high-precision medium is created.

Next, in step S110 of FIG. 7, the output adjustment processor outputs the element output value of the image sensor unit to be adjusted (hereinafter sometimes referred to as the "target unit") whose output is adjusted with reference to the master unit. A target value (hereinafter sometimes referred to as a “target unit target value”) is set.

In step S110, under the control of the output adjustment processor, the master unit having the first adjustment value AJ1 stored in the memory 32 controls an arbitrary medium different from the high-precision medium (hereinafter referred to as "arbitrary medium"). ) is imaged. Then, as shown in FIG. 10, the output adjustment processor sets the element output value OP12 when the arbitrary medium is imaged by the master unit as the target unit target value TG2. It is stored in a memory (not shown) of the device. The element output value OP12 is the element output value after being adjusted by the first adjustment value AJ1.

Here, as an arbitrary medium, it is possible to use a medium with non-uniform reflection density and transmission density (hereinafter sometimes referred to as a "low-precision medium"). A low-precision medium is less expensive than a high-precision medium because the medium error is larger than that of the high-precision medium. An example of a low-precision medium is common copy paper.

Next, in step S115 of FIG. 7, under control from the power adjustment processor, the same arbitrary medium as that used to obtain the target unit target value is imaged by the target unit, and the power adjustment processor As indicated by 10, an element output value OP2 is acquired when an arbitrary medium is imaged by the target unit. The configuration of the target unit is the same as that of the image sensor unit 21 .

Next, in step S120 of FIG. 7, in order to adjust the element output value OP2 to match the target unit target value TG2, the output adjustment processor performs the expression (2 ), and stores the calculated second output adjustment value AJ2 in the memory 32 of the target unit. By storing the second output adjustment value AJ2 in the memory 32, a target unit having the imaging element 31 whose element output is adjusted with reference to the master unit is created.
AJ2=TG2/OP2 (2)

The target unit prepared as described above is attached to the bill validating unit 7 when the bill validating unit 7 is manufactured, and the bill validating unit 7 to which the target unit is attached is attached to the bill handling apparatus 1 when the bill handling apparatus 1 is manufactured. is attached to the

Therefore, the integrated circuit 37 of the target unit attached to the banknote validating unit 7 multiplies the device output value of each imaging device 31 by the second output adjustment value AJ2 when the target unit captures an image of the banknote. Adjust the output of the unit.

As described above, the element output of the master unit is adjusted based on the high-precision medium, and the element output of the target unit is adjusted based on the master unit. Therefore, the element output of the target unit is also adjusted indirectly via the master unit with reference to the high-precision medium in the same way as the element output of the master unit.

The first embodiment has been described above.

[Example 2]
<How to set target unit target value>
In the following, the method of setting the target unit target value will be described with respect to the differences from the first embodiment. Three setting examples, setting example 1, setting example 2, and setting example 3, will be described below for the setting method of the target unit target value.

<Setting example 1>
First, in the same manner as in Example 1, a plurality of master units with adjusted element outputs are produced using the same high-precision media. For example, five master units M1, M2, M3, M4, and M5 are created.

The same arbitrary medium is then imaged by each of the master units M1-M5 under control from the power conditioning processor, which, as shown in FIG. The element output values OP31 to OP35 when the same arbitrary medium is imaged are obtained. FIG. 12 is a diagram for explaining an example of a method for setting target unit target values according to the second embodiment of the present disclosure. The element output value OP31 is the element output value of the master unit M1, the element output value OP32 is the element output value of the master unit M2, the element output value OP33 is the element output value of the master unit M3, and the element output value OP34 is It is the element output value of the master unit M4, and the element output value OP35 is the element output value of the master unit M5.

Then, the output adjustment processor calculates the average value AV3 of the element output values OP31 to OP35 for each image pickup element 31, and sets the average value AV3 as the target unit target value.

<Setting example 2>
First, in the same manner as in Example 1, one master unit is produced using a high-precision medium in which the element output is adjusted.

Then, under the control of the output adjustment processor, the same arbitrary medium is imaged multiple times by one master unit. For example, when the same arbitrary medium is imaged three times by one master unit, and the same arbitrary medium is imaged three times by one master unit as shown in FIG. OP43 is obtained. FIG. 13 is a diagram for explaining an example of a method for setting target unit target values according to the second embodiment of the present disclosure.

Then, the output adjustment processor calculates the average value AV4 of the element output values OP41 to OP43 for each image pickup element 31, and sets the average value AV4 as the target unit target value.

<Setting example 3>
Differences from setting example 1 will be described below.

The output adjustment processor provides, over all the imaging elements 31, an average value AV31 of the element output values OP31, an average value AV32 of the element output values OP32, an average value AV33 of the element output values OP33, an average value AV34 of the element output values OP34, Then, an average value AV35 of the element output values OP35 is calculated.

Next, the output adjustment processor excludes two element output values, ie, the element output value having the maximum value and the element output value having the minimum value among the average values AV31 to AV35 from the element output values OP31 to OP35. , the remaining three element output values are selected from among the element output values OP31 to OP35.

Then, the output adjustment processor calculates the average value AV5 of the three selected element output values for each imaging element 31, and sets the average value AV5 as the target unit target value.

The second embodiment has been described above.

As described above, in the adjustment value calculation method of the present disclosure, first, the output is adjusted using the first medium (the high-precision medium of the embodiment), which is a medium with uniform reflection density and transmission density over the entire surface. A first image sensor unit (master unit in the embodiment) having a first image sensor is produced. Next, based on the first output value, which is the output value of the first imaging device when the first image sensor unit captures an image of the second medium (arbitrary medium of the embodiment) that is an arbitrary medium different from the first medium A target value (target unit target value in the embodiment) is set. Next, a second output value, which is the output value of the second image sensor when the second medium is imaged by the second image sensor unit (target unit in the embodiment) having the second image sensor, is acquired. Then, the adjustment value (the second output adjustment value in the embodiment) used for adjusting the output of the second image sensor when the second image sensor unit captures the image of the paper sheet is set to the second output value and the target value. calculated based on

This makes it possible to adjust the output of the second image sensor unit by using the second medium, which is cheaper than the first medium, instead of the first medium, thus reducing the cost required for adjusting the output of the image sensor unit. can be reduced.

Also, in the adjustment value calculation method of the present disclosure, a plurality of first image sensor units are created, and target values are set based on the respective first output values of the plurality of first image sensor units.

Further, in the adjustment value calculation method of the present disclosure, one first image sensor unit is created, and a plurality of first output values are obtained by imaging the second medium multiple times with the one first image sensor unit. and set the average value of the plurality of first output values as the target value.

By doing this, the accuracy of the target value can be improved.

1 banknote handling device 7 banknote discrimination unit 21 image sensor unit 31 imaging element 32 memory 37 integrated circuit

Claims

creating a first image sensor unit having a first imaging element whose output is adjusted using a first medium that is a medium with uniform reflection density and transmission density over the entire surface;
setting a target value based on a first output value, which is the output value of the first imaging device when the first image sensor unit captures an image of a second medium that is an arbitrary medium different from the first medium;
obtaining a second output value, which is the output value of the second image sensor when the second medium is imaged by a second image sensor unit having a second image sensor;
calculating an adjustment value used for adjusting the output of the second imaging element when the second image sensor unit captures an image of a sheet based on the second output value and the target value;
Adjustment value calculation method.
Create a plurality of the first image sensor units,
setting the target value based on the first output value of each of the plurality of first image sensor units;
The adjustment value calculation method according to claim 1.
creating one said first image sensor unit,
Obtaining a plurality of the first output values by imaging the second medium a plurality of times with one of the first image sensor units;
setting an average value of the plurality of first output values as the target value;
The adjustment value calculation method according to claim 1.
A first image sensor unit having a first imaging element whose output is adjusted using a first medium which is a medium with uniform reflection and transmission densities over the entire surface of an arbitrary medium different from the first medium A target value calculated based on a first output value, which is an output value of the first imaging device when a certain second medium is imaged, and a second image sensor unit having a second imaging device to capture the second medium a memory that stores an adjustment value calculated based on a second output value that is an output value of the second imaging device when an image is captured;
an integrated circuit that uses the adjustment value to adjust the output of the second image sensor when the second image sensor unit captures an image of a paper sheet;
the second image sensor unit having
A paper sheet discrimination unit.