JP2947996B2 - Media reader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for optically reading a sheet-like medium using a one-dimensional transmission sensor.

2. Description of the Related Art In an automatic machine used for trading bills and securities, the density of each area obtained by minutely dividing the inserted bills and securities is measured by this type of apparatus. Is determined using the measurement result.

[0003]

2. Description of the Related Art An inserted medium (a bill or a bill) is transported inside an automatic machine and sent to an optical sensor. The light sensor is provided with a light emitting section in which light emitting elements are arranged and a light receiving section in which light receiving elements are arranged, and a medium to be inserted is transported between the light emitting section and the light receiving section.

The output light of each light emitting element passes through the medium and is received by the corresponding light emitting element, and the output signal of each light receiving element is subjected to A / D conversion to obtain digital data representing the pattern density of the medium in gradation. It is said.

In an automatic machine, these data are compared with corresponding data of a reference medium, and it is determined from the result of the comparison whether or not the input medium is legitimate.

However, each light emitting element of the optical sensor deteriorates with aging. Therefore, conventionally, the amount of light emission of the optical sensor is controlled as described below to absorb the aging of the sensor.

In FIG. 9, the light receiving amount D is a value output by the light receiving unit when the medium does not exist between the light emitting unit and the light emitting unit does not emit light (light receiving amount offset).
When the amount of light emission is increased, the output of the light receiving section rises sharply from the amount of received light A with the characteristic 900 and saturates at the point B.

When a medium is present between the light emitting section and the light receiving section, the output of the light receiving section gradually rises from the light receiving amount A with the characteristic 902 in FIG.
Saturates at a point.

When the product is shipped, the above characteristics 900, 9
02 is measured for all the light receiving elements of the light receiving section and written in the internal memory, and the dynamic range [D, E] in FIG.
The light emission amount of each light emitting element is determined so as to obtain a light amount that can ensure the above.

In actual operation, the characteristic 904 of each light receiving element is measured immediately before the user inserts the medium in a state where no medium exists. Next, all the non-media characteristics 900 at the time of shipment are read out and corresponded to the non-media characteristics 904.
The ratio of the mediumless property 904 at the time of operation deteriorating from the mediumless property 900 at the time of shipping is obtained for each light receiving element.

Further, when the medium is present between the light emitting section and the light receiving section, the characteristics 902 of the respective light receiving elements measured at the time of shipment are read out, and the deterioration of the characteristics 9904 measured without the medium is measured. Based on the ratio, the characteristic 906 of each light receiving element when the medium is transported between the light emitting unit and the light receiving unit during operation is predicted.

That is, if the characteristic 904 is inclined by a certain ratio with respect to the characteristic 900, the characteristic 906 also becomes the characteristic 9
Each light receiving characteristic 906 in actual operation is estimated on the assumption that the light receiving characteristics are inclined by a similar ratio from 02.

When the light emission control of each light emitting element is performed so as to obtain these characteristics 906, the saturation point C at the time of shipment shifts to the saturation point F during operation, and as a result, the dynamic range exactly the same as that at the time of shipment is obtained. [D, E] is always obtained during operation.

Therefore, it is possible to accurately detect the transmission density of the medium irrespective of the deterioration of the optical sensor. Therefore, it is necessary to always accurately determine whether or not the transmission pattern of the inserted medium is normal. Becomes possible.

[0015]

When a medium piece remains between the light emitting portion and the light receiving portion for some reason, the characteristic 904 in the non-media state is greatly inclined to almost the characteristic 902 with the remaining medium piece.

Accordingly, the characteristic 906 predicted from the mediumless characteristic 904 is also greatly inclined, and the saturation point F moves to a position far away from the saturation point at the time of shipment to the right side in FIG. For this reason, the above-mentioned light emission amount control is performed erroneously, and as a result, the light emission amount in the remaining portion of the medium piece becomes extremely large in order to secure a necessary dynamic range.

The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to correct the aging of an optical sensor correctly even when a medium piece remains in the sensor. An object of the present invention is to provide a device that can be used.

[0018]

In order to achieve the above object, the device according to the first invention is configured as shown in FIG. 1, and the device shown in FIG.
And the light receiving unit 16 in which the light receiving elements 14 are arranged are arranged to face each other, and the output light of each light emitting element 10 is transmitted through the medium 18 inserted between the light emitting unit 12 and the light receiving unit 16 so that the corresponding light receiving element 14, a medium image capturing unit 22 that captures a value of a signal output from each light receiving element 14 when the medium 18 is inserted between the light emitting unit 12 and the light receiving unit 16. When the medium 18 is not inserted between the light emitting section 12 and the light receiving section 16, the value of the signal output from each light receiving element 14 does not reach the allowable value in the mediumless state. Abnormal light quantity calculating means 24 for calculating the number of light emitting elements, and light emitting quantity correcting means 26 for correcting the light emitting quantity of each light emitting element 10 when the calculated number has reached a preset number. I have.

The device according to the second invention is configured as shown in FIG. 2. The device shown in FIG. 2 is composed of a light emitting portion 12 in which light emitting elements 10 are aligned and a transmission light receiving portion 16 in which light receiving elements 14 are aligned.
Are arranged in parallel with the light-emitting unit 12, and the medium 18 inserted between the light-emitting unit 12 and the transmission light-receiving unit 16 is attached to each light-emitting element 10.
Is transmitted to the corresponding light-receiving element 14 of the transmission light-receiving section 16 and reflected by the medium 18.
Sensor 32 in which the output light is provided to the corresponding light receiving element 28 of the reflection light receiving unit 30, the light emitting unit 12 and the transmission light receiving unit 16
Medium image capturing means 34 for capturing a value of a signal output from each light receiving element 14 of the transmission light receiving section 16 when the medium 18 is inserted between the light emitting section 12 and the transmission light receiving section 1
When the medium 18 is not inserted between the light receiving elements 6 and 6, the abnormal light receiving element 14 in which the value of the signal output from each light receiving element 14 of the transmission light receiving section 16 does not reach the allowable value in the mediumless state is specified. An abnormal element specifying means 36 which performs the processing and checks the value of the signal output from the light receiving element 28 of the reflection light receiving section 30 corresponding to the light receiving element 14 which has been specified as abnormal, and determines whether the medium piece is in contact with the light emitting section 12 and the transmission light receiving section 16. A medium piece remaining / absence determining means 38 for determining whether or not the medium piece remains between the light emitting element and the light emitting element identified as abnormal when the medium piece does not remain between the light emitting section 12 and the transmission light receiving section 16 And a light emission amount correcting means 40 for correcting the light emission amount of No. 10.

[0020]

In the first invention and the second invention, the optical sensor 2
The transmission images of the medium 18 detected at 0, 32 are taken into the medium image taking means 22, 34.

In the first invention, when a medium piece remains in the optical sensor 20, it is considered that the number of abnormal light receiving elements 14 is small, and therefore, the light receiving output (characteristic 90
When the number of the light receiving elements 14 in which 4) is abnormal is large, it is determined that those abnormalities are caused by the deterioration of the optical sensor 20, and the light emission amount of the optical sensor 20 is corrected.

In the second invention, the reflection light receiving section 30 to which the output light of the light emitting section 12 reflected by the medium 18 is provided is provided. Is specified, the output value of the reflection-side light receiving element 28 corresponding to the abnormal light receiving element 14 is checked.

If the abnormality at this time is caused by a medium piece remaining in the optical sensor 32, the amount of light received by the reflection-side light receiving element 28 in the remaining piece portion is almost the same as when the medium 18 was inserted into the optical sensor 32. The same and many, and the optical sensor 3
In the case of the deterioration of No. 2, it becomes slight.

Therefore, by checking the output value of the reflection-side light receiving element 28 corresponding to the abnormal light receiving element 14, the presence or absence of the medium piece can be clearly determined. Therefore, when the abnormality is caused by deterioration of the optical sensor 32 (when a medium piece does not remain in the optical sensor 32), the light emission amount of the sensor 32 is corrected.

[0025]

FIG. 3 shows the overall structure of the embodiment.
The medium 18 put into the automatic machine is conveyed to the optical sensor 42 in FIG.

The output of the optical sensor 42 is amplified by an amplifier 44 and converted into digital data by an A / D converter 46 before being supplied to a sensor correction unit 48, and is stored in a storage unit 50.
The sensor correction unit 48 compares the sensor characteristics at the time of shipment written in advance with the sensor characteristics at the time of operation indicated by the digitally converted data.

The sensor correction section 48 determines whether or not the optical sensor 42 has deteriorated and whether or not a medium piece remains in the optical sensor 42 based on the comparison result at this time. The control target value of the sensor light emission amount (the characteristic 906 in FIG. 9 when the sensor is deteriorated, and the characteristic 902 in FIG. 9 when the medium piece remains and the sensor is normal) is written to the storage unit 52 in the present embodiment.

Further, the value written to the storage unit 52 is read out to the central processing unit 54 via the sensor correction unit 48, and the light emission amount of the optical sensor 42 is added to this value.
Is controlled by

When the medium 18 is conveyed to the optical sensor 42 and the sensor light emission amount is controlled, the A / D converter 4
The digital data obtained in step 6 is output to another circuit for determining whether or not the transmission pattern of the medium 18 is normal.

FIG. 4 shows an optical sensor 4 used in this embodiment.
2, the light sensor 42 is composed of a light emitting section 58 in which light emitting elements 56 are arranged and a light receiving section 62 in which light receiving elements 60 are arranged.

The light emitting surface of each light emitting element 56 and the light receiving surface of the light receiving element 60 are opposed to each other, and the output light of each light emitting element 56 transmitted through the medium 18 conveyed between the light emitting elements 56 is transmitted to the corresponding light receiving element 60. Incident.

FIG. 5 illustrates the operation of the present embodiment using a flowchart. If it is confirmed that the medium 18 is inserted, the medium 18 does not exist between the light emitting unit 18 and the light receiving unit 62. In this state, the outputs of all the light receiving elements 60 are converted into digital data and input to the sensor correction unit 48, and the mediumless characteristics 904 of FIG. 9 are obtained for each light receiving element 60 (step 500).

Then, all the mediumless characteristics 900 in FIG. 9 are read out from the storage unit 50 to the sensor correction unit 48, and the two characteristics 900 and 904 are compared for each light receiving element 60 (step 502).

At this time, if all of the operating-side characteristics 904 have reached a value obtained by subtracting a fixed ratio (5%) from the corresponding shipping-side characteristic 900, the light receiving elements 60
It is determined that deterioration has not occurred in (optical sensor 42), and it is determined that the light emission amount correction of optical sensor 42 is not performed (step 504).

Further, the characteristic 902 of FIG. 9 measured in the medium presence state and written in the storage unit 50 at the time of shipment is read out from the storage unit 50 and written out to the storage unit 52 as it is (step 506).

A characteristic 9 which does not reach a value obtained by subtracting a certain ratio (5%) from the mediumless characteristic 900 at the time of shipment.
When 04 is confirmed, the number (×) of the light receiving elements 60 having the abnormal characteristic 904 is counted (step 508), and the total number of these is set to a predetermined number (total =
It is determined whether or not N falls within N / 3) (step 5).
10).

At this time, if it is confirmed that the number of light receiving elements of the abnormal characteristic (904) is within the specified number (YES in step 510), the sensor deterioration due to aging progresses uniformly, It is determined that these abnormalities are caused by the remaining pieces of the medium (step 512).

Therefore, it is determined that the correction of the sensor light emission amount is not performed (step 504), and the storage unit 5
The characteristic 902 (the one at the time of shipment) of FIG. 9 which has been written to 0 is written out to the storage unit 52 as it is.

On the other hand, if the number of the light receiving elements 60 having the abnormal characteristic 904 does not fall within the specified number (NO in step 510), it is determined that those abnormalities are caused by sensor deterioration and FIG. Are obtained for all the light emitting elements 56 (step 514), and the storage unit 52
(Step 516).

As described above, according to the present embodiment, it is checked whether or not the medium piece remains in the optical sensor 42 by paying attention to the fact that the deterioration of the optical sensor 42 proceeds uniformly.
If it is confirmed that the medium piece remains, the sensor light emission amount is not corrected, so that the correction can always be performed correctly.

Accordingly, the sensor light emission amount is not erroneously increased greatly in order to secure the dynamic range of the light receiving input. Therefore, it is possible to avoid the deterioration of the light emitting portion 58 due to the remaining medium pieces, Further, it is possible to stably and faithfully express the transmission pattern of the inserted medium 18.

FIG. 6 shows another optical sensor 42. In this optical sensor 42, a light emitting section 58 and a light receiving section 62 are provided on the upper side and the lower side of the medium 18, respectively. )
As described above, it is used as a light transmission type sensor and a light reflection type sensor (the above embodiment only functions as a light transmission type sensor).

In addition, reading from both the front and back surfaces of the medium 18 can be performed simultaneously, so that a transmission pattern and a reflection pattern can be obtained. Therefore, the automatic machine can check the normality of the medium 18 more strictly.

FIG. 8 is a flowchart illustrating the operation of a large-sized apparatus using the optical sensor 42. The mediumless characteristic 904 during operation becomes abnormal as shown in FIG. 7B. When the existence of the light receiving element 60 on the transmission side is confirmed (step 502), the light receiving amount characteristic of the light receiving element 60 on the reflection side corresponding to this is examined (step 80).
0).

FIG. 7 (C) shows the received light amount characteristics of the light reflection type sensor. If a medium piece remains in the optical sensor 42, the mediumless characteristic 904 during operation is recognized as abnormal. The signal value of the output from the light receiving element 60 on the reflection side corresponding to the light receiving element 60 on the transmission side obtained is clearly large.

That is, the amount of light received by the reflection-side light receiving element 28 in the remaining medium piece is almost the same as when the medium 18 is inserted into the optical sensor 32, and is large.
In the case of the deterioration of No. 2, it becomes slight.

Therefore, the medium 18 is supplied to the optical sensor 42 at the time of shipment.
Are inserted and the characteristic 700 of FIG. 7C is measured, and the characteristic 700 when the medium is inserted is written in the storage unit 50 in advance.

When the light receiving characteristic (904) of the corresponding transmission side light receiving element 60 is found to be abnormal, the characteristic 7
00 is read and compared with the characteristics of the reflection-side light receiving element 60 examined as described above (step 802).

At this time, if it is confirmed that the light receiving characteristic of the reflection-side light receiving element 60 matches the characteristic 700 at the time of shipment, an abnormality in which the amount of transmitted light is reduced is caused by the medium piece remaining in the optical sensor 42. Is determined (step 512), and therefore, it is determined that the light emission amount is not to be corrected for that portion (step 504).

When it is confirmed from the above comparison result that the abnormality in which the amount of transmitted light is reduced is not due to the medium piece remaining in the optical sensor 42, the amount of emitted light is corrected in the same manner as described above (step 514). .

As described above, in the case of a large-sized device in which the optical sensor 42 can also function as a reflection type, the function can be used to directly detect a medium piece remaining in the sensor 42. Therefore, it is possible to clearly identify whether the cause of the abnormality in which the amount of received light is reduced when the medium is absent is the deterioration of the optical sensor 42 or the remaining of the medium piece.

By using the above-described processing (see FIG. 5) in the simple sensor (the optical sensor 42 in FIG. 4) together, the error in which the light emission amount of the optical sensor 42 is corrected by the remaining medium piece is completely eliminated. (Only when processing time is allowed).

[0053]

As described above, according to the present invention, the medium piece remaining on the optical sensor can be confirmed, so that the correction of the sensor light emission amount can always be performed correctly regardless of the remaining, so that the sensor light emission amount can be corrected. Does not accidentally increase significantly. For this reason, it is possible to avoid the deterioration progress of the light emitting section due to the medium piece, and it is also possible to stably and faithfully express the transmission pattern of the inserted medium.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the first invention.

FIG. 2 is a diagram illustrating the principle of the second invention.

FIG. 3 is an explanatory diagram of the overall configuration of the first embodiment.

FIG. 4 is a diagram illustrating a configuration of an optical sensor according to a first embodiment.

FIG. 5 is a flowchart illustrating the operation of the first embodiment.

FIG. 6 is an explanatory diagram of a configuration of an optical sensor according to a second embodiment.

FIG. 7 is a diagram illustrating the operation of the optical sensor according to the second embodiment.

FIG. 8 is a flowchart illustrating the operation of the second embodiment.

FIG. 9 is an explanatory diagram of an operation of a conventional optical sensor correction.

[Explanation of symbols]

 Reference Signs List 18 medium 42 optical sensor 44 amplifying unit 46 A / D converting unit 48 sensor correcting unit 50 storage unit 52 storage unit 54 central processing unit 56 light emitting element 58 light emitting unit 60 light receiving element 62 light receiving unit

Claims (2)

(57) [Claims] A light emitting unit (1) in which light emitting elements (10) are aligned.
2) and a light receiving section (16) in which the light receiving elements (14) are aligned are arranged to face each other, and a medium (18) inserted between the light emitting section (12) and the light receiving section (16) is placed on each light emitting element. A medium (18) between the light sensor (20) through which the output light of (10) is transmitted and given to the corresponding light receiving element (14), and the light emitting section (12) and the light receiving section (16);
Medium image capturing means (22) which captures the value of the signal output from each light receiving element (14) when is inserted.
And a medium (18) between the light emitting section (12) and the light receiving section (16).
Means for calculating the number of abnormal light receiving elements (14) in which the value of the signal output from each light receiving element (14) does not reach the permissible value in the mediumless state when no is inserted. 24); and a light emission amount correcting means (26) for correcting the light emission amount of each light emitting element (10) when the calculated number has reached a preset number. Media reader. 2. A light emitting unit (1) in which light emitting elements (10) are aligned.
2) Transmitted light receiving section (16) in which light receiving element (14) is aligned
Are arranged opposite to each other, and the reflection light receiving portion (30) in which the light receiving elements (28) are aligned is arranged in parallel with the light emitting portion (12) and inserted between the light emitting portion (12) and the transmission light receiving portion (16). The output light of each light emitting element (10) is transmitted through the medium (18), is given to the corresponding light receiving element (14) of the transmission light receiving section (16), and is reflected by the medium (18). The output light of the corresponding light receiving element (28) of the reflection light receiving section (30)
And a medium (1) between the light emitting unit (12) and the transmitting and receiving unit (16).
8) medium image capturing means (34) for capturing the value of the signal output from each light receiving element (14) of the transmission light receiving section (16) when the light transmission section (16) is inserted; Medium (1) between
8) When the light receiving element (14) of the transmission light receiving section (16) is not inserted, the value of the signal output from each light receiving element (14) of the transmission light receiving section (16) does not reach the allowable value in the mediumless state. The medium piece emits light by examining the value of the signal output from the abnormal element specifying means (36) for specifying and the light receiving element (28) of the reflection light receiving section (30) corresponding to the light receiving element (14) specified as abnormal. Section (12) and transmitted light receiving section (16)
Means for determining whether or not the medium piece remains between the light emitting unit (12) and the transmitting and receiving unit (16); Light emission amount correcting means (40) for correcting the light emission amount of the light emitting element (10) specified as abnormal.
A medium reading device, comprising: