JP2011227824A - Symbol code reader and control program for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a symbol code reader capable of preventing double reading of a symbol code and achieving accurate information collection without putting burden on an operator and to provide a control program for the symbol code reader.SOLUTION: A symbol code included in an image taken by an image sensor 22 is decoded by a decoder 23, and a first determination section 282 determines whether or not first code information generated as a result of decoding is the same as second code information generated just before. When both the code information data coincide with each other, a second determination section 283 determines whether or not an article to which the symbol code expressing the first code information is attached is the same as an article to which the symbol code expressing the second code information is attached based on images taken by the image sensor 22 from the photographing of a second code information generation source image up to the photographing of a first code information generation source image. When both the articles coincide with each other, an output control section 284 outputs the first code information.

Description

  Embodiments described herein relate generally to a symbol code reading apparatus that reads a symbol code such as a barcode attached to an article and outputs code information, and a control program therefor.

  The mainstream of the symbol code reader for recognizing a symbol such as a barcode attached to an article such as a commodity is a laser system that scans laser light. However, on the other hand, in recent years, a so-called camera imaging method has been developed in which a two-dimensional image of an article with a symbol is taken by an imaging means and a symbol code is read from this image. This type of symbol code reader converts a symbol code image into an analog signal through an imaging lens and converts it to an analog signal. The analog signal is converted into a binarized output by a binarizing circuit, and then sent to a decoder. The decoded numerical value is output.

  If the same symbol code is kept on the reading surface after the symbol code is read by the symbol code reader, the symbol code may be read again. When such double reading occurs, one article is handled as if there are two, and accurate information collection is prevented.

  Conventionally, means for preventing double reading as described above have been taken in the symbol code readers of the laser system and the camera imaging system. The mainstream method is to activate some double reading prevention function when the code information read from the symbol code is the same as the code information read last time.

JP-A-11-110475

  When trying to prevent double reading using code information, it is useless when the symbol codes are the same even though the symbol codes attached to different items are actually read. The function for preventing double reading works.

  Therefore, the function for preventing double reading itself may hinder information collection, and depending on the specific processing contents of the function, it may be a burden on the operator of the symbol code reading device.

  Under such circumstances, there has been a demand for a symbol code reading apparatus that prevents double reading of a symbol code without imposing a burden on an operator and enables accurate information collection.

In order to achieve the above object, a symbol code reading apparatus according to an embodiment includes an imaging unit, a decoding unit, a first determination unit, a second determination unit, and an output control unit.
The imaging means images an article attached with a symbol code representing code information. The decoding unit recognizes a symbol code included in an image captured by the imaging unit, decodes the recognized symbol code, and generates code information. The first determination means includes first code information which is code information newly generated by the decoding means, and second code information which is code information generated by the decoding means immediately before the first code information is generated. It is determined whether the code information matches. When the first determination unit determines that the first code information and the second code information coincide with each other, the second determination unit captures an image that is a generation source of the second code information, and then An article to which a symbol code representing the first code information is attached based on an image captured by the imaging unit until an image that is a generation source of the first code information is captured, and the second code It is determined whether the article with the symbol code representing the information is the same. The output control means is provided with a symbol code representing the first code information when the first determination means determines that the first code information does not match the second code information and when the second determination means. The first code information is output when it is determined that the article to which the symbol code representing the second code information is attached is not the same.

The schematic diagram which shows the use condition of the barcode scanner in 1st Embodiment. The block diagram which shows the principal part structure of the barcode scanner in the embodiment. Schematic which shows the AA cross section of the barcode scanner shown in FIG. Schematic which shows the BB cross section of the barcode scanner shown in FIG. The figure for demonstrating the reading range by the barcode scanner in the embodiment. 6 is a flowchart for explaining the operation of the barcode scanner in the embodiment. The block diagram which shows the principal part structure of the barcode scanner in 3rd Embodiment. 6 is a flowchart for explaining the operation of the barcode scanner in the embodiment. FIG. 10 is a schematic diagram illustrating a usage state of a barcode scanner according to a fourth embodiment. The block diagram which shows the principal part structure of the barcode scanner in the embodiment. 6 is a flowchart for explaining the operation of the barcode scanner in the embodiment.

Each embodiment will be described below with reference to the drawings.
Each embodiment described here exemplifies a barcode scanner used for reading a barcode attached to a product in a retail store or the like as a symbol code reader.

(First embodiment)
A first embodiment will be described.
FIG. 1 is a schematic diagram showing a usage state of the barcode scanner 1. The barcode scanner 1 is provided on the side surface of the information processing terminal 2. The information processing terminal 2 is, for example, a POS (Point Of Sales) terminal used for a checkout operation at a retail store or the like, a product code input device provided on a cash register counter connected to the POS terminal, and the like.

  The barcode scanner 1 is formed by fitting a light transmissive glass member 11 into a rectangular parallelepiped case 10. When a barcode (symbol code) attached to a product as a subject is placed on the glass member 11, the barcode is read by the barcode scanner 1, and a product code (code information) represented by the barcode is obtained. Input to the control circuit of the information processing terminal 2.

  The information processing terminal 2 performs predetermined information processing using the product code input from the barcode scanner 1. For example, when the information processing terminal 2 is the POS terminal, a PLU (Price Look Up) file is searched using the input product code as a key, and product information including the unit price of the product indicated by the product code is read. The product information of the purchased product is stored in a memory for temporarily storing the product information. If the information processing terminal 2 is the product code input device, the input product code is output to the POS terminal. This POS terminal executes processing as described above.

  FIG. 2 is a block diagram showing the main configuration of the barcode scanner 1. The barcode scanner 1 includes a light source 20, a lens 21, an image sensor 22, a decoder 23, a light source driving circuit 24, a luminance measuring unit 25, a memory 26, a connection interface 27, and a control unit 28.

  The light source 20 functions as an illuminating unit in the present embodiment, and is configured by LED light sources 201 to 204 (see FIG. 4) that illuminate a subject covered with the glass member 11.

  The lens 21 forms an image on the image sensor 22 of the reflected light that is irradiated from the light source 20 and reflected back to the subject.

  The image sensor 22 functions as an imaging unit in the present embodiment, and is configured by an imaging element such as a charge coupled diode (CCD) or a complementary metal-oxide semiconductor (CMOS), and is an optical image formed by the lens 21. Multi-tone image data is generated by photoelectrically converting. The generated image data is output to the decoder 23 and the control unit 28.

  The decoder 23 functions as a decoding unit in the present embodiment, recognizes a barcode included in the image data input from the image sensor 22, and decodes the recognized barcode to generate a product code. The generated product code is notified to the control unit 28.

  The light source drive circuit 24 controls the energization timing to the LED light sources 201 to 204 to turn on / off the LED light sources 201 to 204.

  The luminance measuring unit 25 functions as a luminance measuring unit in the present embodiment, and measures the average luminance Bave of the entire image data input from the image sensor 22 via the control unit 28. Specifically, the average luminance Bave is calculated by measuring the luminance of all the pixels constituting the image data, adding them, and dividing by the number of pixels of the image data. The average luminance Bave measured by the luminance measuring unit 25 is output to the memory 26.

  The memory 26 is, for example, an EEPROM, and stores the product code generated by the decoder 23, the average luminance Bave measured by the luminance measuring unit 25, and the like. In particular, in the present embodiment, the average luminance Bave measured by the luminance measuring unit 25 from when a certain product code is generated by the decoder 23 to when the next product code is generated, and both of these product codes (first , Second code information).

  The connection interface 27 connects the control unit 28 and the information processing terminal 2 via a predetermined communication cable so that they can communicate with each other.

  The control unit 28 includes a microprocessor, a ROM (Read Only Memory), and the like. In particular, the control unit 28 executes functions of the main control section 281, the first determination section 282, the second determination section 283, and the output control section 284 by executing a control program stored in the ROM.

  The main control section 281 executes various processes relating to barcode reading, such as control of each part constituting the control circuit of the barcode scanner 1.

  The first determination section 282 compares the two product codes stored in the memory 26 as described above, and determines whether or not they match.

  The second determination section 283 generates the product displayed in the image data that is the generation source of the product code newly generated by the decoder 23, and the product code generated immediately before the product code is generated by the decoder 23. It is determined whether or not the product displayed in the original image data is the same. In particular, in the present embodiment, the average luminance Bave stored in the memory 26 and the threshold value Bs are used as a criterion for determining whether or not both products are the same.

  The threshold value Bs is stored in the ROM or the like, and its value is set to a value obtained by multiplying the average luminance of image data that is entirely white by a predetermined ratio. The whole image data that is white is an image with the maximum luminance that can be imaged by the image sensor 22 as a whole. For example, if the luminance is represented by 8 bits, it is “255”. The predetermined ratio is derived empirically, experimentally, or theoretically so that no product or the like is obscured on the glass member 11 when generating image data in which at least the average luminance is equal to or less than the threshold value Bs. Value is set. In determining the value, for example, the state of illumination around the barcode scanner 1, the illumination capability of the light source 20, the performance of the image sensor 22, and the like are considered.

  The output control section 284 is generated by the decoder 23 when the first determination section 282 determines that the two product codes do not match and when the second determination section 283 determines that the two products are not identical. The product code is output to the information processing terminal 2.

FIG. 3 is a schematic view showing a cross section AA of the barcode scanner 1 shown in FIG. 1, and FIG. 4 is a schematic view showing a cross section BB of the barcode scanner 1 shown in FIG.
As shown in FIG. 3, the case 10 is formed by the top cover 12 and the bottom cover 13. The light source 20, the illumination board 30 to which the light source 20 is attached, the lens 21, and the image sensor are formed in the case 10. 22 and the control board 31 are accommodated. The light source drive circuit 24 is mounted on the illumination board 30, and the luminance measurement unit 25, the memory 26, and the control unit 28 are mounted on the control board 31. The lines for electrically connecting the respective parts are not shown. The broken line in the figure is the housing surface of the information processing terminal 2. That is, the case 10 constituted by the top cover 12 and the bottom cover 13 is attached such that a part protrudes from the casing surface of the information processing terminal 2 and the other part is embedded in the information processing terminal 2.

  On the top surface 12a of the top cover 12, a bowl-shaped inclined portion 12b having a rectangular edge and an open bottom is formed. The glass member 11 is fitted into the top cover 12 so as to block the inclined portion 12b and be flush with the top surface 12a. The lens 21 is fixed to the image sensor 22 so that its central axis passes through the center of the inclined portion 12 b of the top cover 12.

  The illumination board 30 is provided between the glass member 11 and the lens 21, and a circular opening 30 a is formed around the extension line of the central axis of the lens 21 so that the subject image reaches the lens 21. Yes.

  The LED light sources 201 to 204 are each composed of two LEDs in order to ensure a wide adjustable light amount width. The LED light source 201 is inclined on the upper left side of the opening 30a, the LED light source 202 is inclined on the lower left side of the opening 30a, the LED light source 203 is inclined on the upper right side of the opening 30a, and the LED light source 204 is inclined on the lower right side of the opening 30a. It is positioned on a substantially extended line of the inclination of the portion 12 b and is fixed to the lighting board 30.

  The reading range by the barcode scanner 1 having such a configuration will be described with reference to FIG. A reading range 40 is within a frame indicated by a broken line in the figure. The range 40 is a range partitioned by, for example, four side surfaces formed on a substantially extension line of the inclined portion 12b and a limit surface 41. The limit surface 41 is a surface indicating a limit position where image data generated based on the reflected light from the subject within the four side surfaces can have a sharpness sufficient to decode the barcode.

  When the light source 20 is turned on and there is a subject or an operator's hand in the reading range 40 as in the product 51, a sufficient amount of reflected light enters the lens 21 from the subject or the like. Therefore, the image data generated based on the reflected light is sufficiently bright, and the average luminance Bave of the image data is a value exceeding the threshold value Bs.

  On the other hand, when the light source 20 is turned on, if the subject or the operator's hand is outside the four side surfaces of the reading range 40 like the product 52, the light emitted from the light source 20 does not strike the subject. Therefore, since sufficient reflected light does not enter the lens 21, the image data becomes dark, and the average luminance Bave of the image data becomes a value lower than the threshold value Bs.

  On the other hand, when the light source 20 is turned on, if there is a subject or an operator's hand in the four side surfaces of the reading range 40 and outside the limit surface 41 like the product 53, the subject is emitted from the light source 20. Although the light reaches, sufficient reflected light cannot be obtained. Accordingly, the image data becomes dark, and the average luminance Bave of the image data becomes a value lower than the threshold value Bs.

Next, the operation of the barcode scanner 1 will be described.
FIG. 6 is a flowchart for explaining the operation of the barcode scanner 1 in the present embodiment. The processing shown in this flowchart is started in response to an instruction to read a barcode from the information processing terminal 2, for example.

  In this process, first, the main control section 281 of the control unit 28 generates variables X and Xp in the memory 26 (step S101), and instructs the light source drive circuit 24 to start illumination (step S102). When receiving this instruction, the light source driving circuit 24 starts energizing the LED light sources 201 to 204 and turns on the LED light sources 201 to 204.

  After the illumination is started, the image sensor 22 photoelectrically converts the optical image formed by the lens 21 to generate image data (step S103). The image data is output to the decoder 23 and sent to the luminance measuring unit 25 via the control unit 28.

  When the image data is received from the image sensor 22, the luminance measuring unit 25 measures the average luminance Bave of the entire image data and stores the result in the memory 26 (step S104). When the image data is received from the image sensor 22, the decoder 23 tries to recognize the barcode from the image data, and if the barcode is recognized, tries to decode it (step S105). When the decoder 23 successfully decodes the barcode, the decoder 23 notifies the control unit 28 of the product code generated by the decoding.

  Thereafter, the main control section 281 determines whether or not decoding is successful (step S106). When the product code is not notified from the decoder 23, the main control section 281 determines that the decoding has failed (No in step S106). In this case, the main control section 281 does not perform other processing, and generates image data by the image sensor 22 (step S103), measures the average luminance Bave by the luminance measuring unit 25, and stores it in the memory 26 (step S104), decoder 23 (step S105) is repeated. That is, the average luminance Bave is accumulated and stored in the memory 26 as many times as the processes of steps S103 to S105 are executed until the decoding is successful. The average luminance Bave stored in the memory 26 is erased immediately before the first step S103 is executed after successful decoding, for example.

  Eventually, when a product is picked up in an appropriate posture within the reading range 40, the barcode attached to the product is clearly reflected in the image data, and the barcode is decoded by the decoder 23. At this time, when the product code is notified from the decoder 23, the main control section 281 determines that the decoding has succeeded (Yes in step S106), and describes the product code received from the decoder 23 in the variable X formed in the memory 26. (Step S107).

  Next, the first determination section 282 of the control unit 28 compares the variable X and the variable Xp to determine whether or not they match (step S108). If the first determination section 282 determines that the variable X and the variable Xp do not match (No in step S108), the output control section 284 of the control unit 28 outputs the product code described in the variable X to the information processing terminal 2. (Step S109). Further, the main control section 281 rewrites the contents of the variable Xp in the memory 26 with the product code described in the variable X (step S110). Thereafter, the process returns to step S103 again.

  On the other hand, when it is determined by the first determination section 282 that the variable X and the variable Xp match (Yes in step S108), the second determination section 283 displays the image data that is the generation source of the product code described in the variable X. It is determined whether or not the displayed product is the same as the product displayed in the image data that is the generation source of the product code described in the variable Xp (step S111). This determination is performed after the image data that is the generation source of the product code described in the variable Xp is captured until the image data that is the generation source of the product code described in the variable X is captured. Is performed by comparing a series of average luminances Bave stored in the threshold value Bs with the threshold value Bs.

  If even one of the series of average luminances Bave is below the threshold value Bs, the image data that is the generation source of the product code described in the variable Xp is captured and then the product described in the variable X The product and the operator's hand holding the product are out of the reading range 40 as shown in FIG. 5 until the image data as the code generation source is captured. That is, since the product that has been trapped on the glass member 11 at the time of decoding the product codes described in the variable X and the variable Xp is likely to be a different product although the product code is the same, the second determination section 283 is used. Determines that the two products are not identical (No in step S111). In this case, the output control section 284 outputs the product code described in the variable X to the information processing terminal 2 (step S109), and the main control section 281 stores the content of the variable Xp in the memory 26 in the variable X. The code is rewritten (step S110). Thereafter, the process returns to step S103.

  On the other hand, if all of the series of average luminances Bave exceed the threshold value Bs, the product code described in the variable X is captured after the image data that is the generation source of the product code described in the variable Xp is captured. Until the image data that is the generation source of the image is captured, the product and the operator's hand holding it are in the reading range 40 as shown in FIG. That is, since it is highly likely that the product that has been placed on the glass member 11 when the product codes described in the variable X and the variable Xp are decoded is the same product, the second determination section 283 has the same product. (Yes in step S111). In this case, without outputting the product code by the output control section 284, image data is again generated by the image sensor 22 (step S103), the average luminance Bave is measured by the luminance measuring unit 25, and stored in the memory 26 (step). S104), decoding by the decoder 23 (step S105) is repeated.

  Note that the processing according to the flowchart shown in FIG. 6 is continued until, for example, the information processing terminal 2 gives an instruction to finish reading the barcode. The information processing terminal 2 uses the product code output from the barcode scanner 1 in a series of processes to perform accounting for the product indicated by each product code.

  As described above, the barcode scanner 1 according to the present embodiment is a generation source of both product codes when the product code newly generated by the decoder 23 matches the product code generated immediately before the code. Based on the image data captured during the image data, it is determined whether or not the products for which both product codes are represented are the same. Then, the newly generated product code is output to the information processing terminal 2 only when it is determined that the two products are not the same. With such a configuration, since the function for preventing double reading works only when the same product is continuously placed on the barcode scanner 1, accurate information collection is possible. The operator is not burdened by the same function.

(Second Embodiment)
Next, a second embodiment will be described.
This embodiment is different from the first embodiment in that the threshold value Bs is dynamically set. The same portions as those in the first embodiment are denoted by the same reference numerals, and redundant description is performed only when necessary.

  The threshold value Bs in the present embodiment is calculated by multiplying the average luminance Bave of the image data successfully decoded by the decoder 23 by a predetermined ratio R. The ratio R is when the average brightness of the image data captured at a certain timing is reduced to a level obtained by multiplying the average brightness of the image data captured with a product or the like in the reading range 40 by the ratio R. The value is set such that it can be determined that a product or the like has been issued from the reading range 40. The specific value of the ratio R is derived empirically, experimentally or theoretically.

Next, the operation of the barcode scanner 1 will be described with reference to the flowchart shown in FIG.
In the process of step S111 in the present embodiment, the second determination section 283 first calculates the threshold value Bs by multiplying the average luminance Bave of the image data that is the product code generation source described in the variable Xp by the ratio R. Then, using the threshold value Bs thus calculated and the series of average luminances Bave stored in the memory 26, the identity of the product is determined as described in the above embodiment.

  As described above, the barcode scanner 1 according to the present embodiment multiplies the threshold Bs used for determining the identity of a product by the predetermined ratio R to the average luminance Bave of the image data successfully decoded by the decoder 23. To set it dynamically. In this way, even when the intensity of the reflected light from the product covered by the glass member 11 due to ambient illumination or sunlight varies, the influence can be absorbed.

  Needless to say, there is an effect that accurate information can be collected as in the first embodiment.

(Third embodiment)
Next, a third embodiment will be described.
In this embodiment, the bar code pattern of the bar code from the image data captured while both the product codes are read is used to identify the identity of the product from which the product code is newly read and the product from which the product code is read immediately before. This is different from each of the embodiments described above in that the determination is made using the time when it cannot be recognized. The same portions as those in the above-described embodiments are denoted by the same reference numerals, and redundant description is performed only when necessary.

  FIG. 7 is a block diagram showing a main configuration of the barcode scanner 1 in the present embodiment. The barcode scanner 1 includes a timer 251 that functions as a time measuring unit in this embodiment, instead of the luminance measurement unit 25 described in the above embodiments.

  The timer 251 is controlled by the control unit 28 and determines the time from when the decoder 23 cannot recognize the presence of the barcode from the image data captured by the image sensor 22 until the next recognition of the presence of the barcode. Keep time.

  The memory 26 in this embodiment stores the product code generated by the decoder 23, the time T counted by the timer 251 and the like.

  In addition, the second determination section 283 in the present embodiment uses the time T stored in the memory 26 and the threshold value Ts as a determination criterion as to whether or not both products are the same. The threshold value Ts is stored in the ROM or the like, and is slightly shorter than the average time required for the operator to put a product on the glass member 11 and then put another product on the glass member 11. So that the value is derived empirically, experimentally or theoretically. In setting specific values, for example, the shape, size, and weight of a product sold at a store, the skill level of an operator, the layout around a cash register, and the like are considered.

Next, the operation of the barcode scanner 1 will be described.
FIG. 8 is a flowchart for explaining the operation of the barcode scanner 1 in this embodiment. The process shown in this flowchart is started in response to an instruction to start barcode reading from the information processing terminal 2, for example.

  In this process, first, the main control section 281 of the control unit 28 generates variables X and Xp in the memory 26 (step S201), and instructs the light source drive circuit 24 to start illumination (step S202). When receiving this instruction, the light source driving circuit 24 starts energizing the LED light sources 201 to 204 and turns on the LED light sources 201 to 204.

  After the illumination is started, the image sensor 22 photoelectrically converts the optical image formed by the lens 21 to generate image data, and outputs it to the decoder 23 (step S203).

  When receiving the image data from the image sensor 22, the decoder 23 tries to recognize the barcode from the image data, and if the barcode is recognized, tries to decode the barcode (step S204). Bar code recognition is performed by searching a bar pattern constituting a bar code from image data. If even a part of the bar pattern is found, it is determined that the bar code has been recognized, and decoding is attempted. When the barcode can be recognized, the decoder 23 notifies the control unit 28 of the fact, and when the barcode is successfully decoded, the decoder 23 notifies the control unit 28 of the product code generated by the decoding.

  After trial of decoding by the decoder 23, the main control section 281 determines whether or not the barcode is recognized by the decoder 23 (step S205). When the notification indicating that the barcode has been recognized has not been received from the decoder 23, the main control section 281 determines that the barcode has not been recognized (No in step S205). In this case, the main control section 281 commands the timer 251 to start timing (step S206). When this command is received, the timer 251 continues the timing operation if it is in a timing operation, and starts the timing operation if it is stopped.

  On the other hand, after receiving a notification from the decoder 23 that the barcode has been recognized after the trial of decoding by the decoder 23, the main control section 281 determines that the barcode has been recognized (in step S205). Yes). In this case, the main control section 281 stores the time T measured by the timer 251 in the memory 26 (step S207), stops the time measuring operation of the timer 251 and resets the time T to zero (step S208).

  After the process of step S206 or step S208, the main control section 281 determines whether the decoding by the decoder 23 is successful (step S209). If the product code is not output from the decoder 23, the main control section 281 determines that decoding has failed (No in step S209). In this case, the processes in steps S203 to S208 are repeated. That is, the time count T is accumulated and stored in the memory 26 as many times as the processing of step S207 is executed until the decoding is successful. The time count T stored in the memory 26 is deleted immediately before the first step S203 is executed after successful decoding, for example.

  Eventually, when a product is picked up in an appropriate posture within the reading range 40, the barcode attached to the product is clearly reflected in the image data, and the barcode is decoded by the decoder 23. If the product code notified from the decoder 23 is received at this time, the main control section 281 determines that the decoding is successful (Yes in step S209). At this time, the main control section 281 describes the product code received from the decoder 23 in the variable X formed in the memory 26 (step S210).

  Next, the first determination section 282 of the control unit 28 compares the variable X and the variable Xp to determine whether or not they match (step S211). If the first determination section 282 determines that the variable X and the variable Xp do not match (No in step S211), the output control section 284 of the control unit 28 outputs the product code described in the variable X to the information processing terminal 2. (Step S212). Further, the main control section 281 rewrites the contents of the variable Xp in the memory 26 with the product code described in the variable X (step S213). Thereafter, the process returns to step S203.

  On the other hand, when it is determined by the first determination section 282 that the variable X and the variable Xp match (Yes in step S211), the second determination section 283 displays the image data that is the generation source of the product code described in the variable X. It is determined whether the displayed product is the same as the product displayed in the image data that is the generation source of the product code described in the variable Xp (step S214). This determination is performed after the image data that is the generation source of the product code described in the variable Xp is captured until the image data that is the generation source of the product code described in the variable X is captured. This is performed by comparing a series of measured time T stored in the above and a threshold value Ts.

  If even one of the series of measured times T exceeds the threshold value Ts, the image data that is the source of the product code described in the variable Xp is captured and then the product described in the variable X There is a high possibility that the product on the glass member 11 has been replaced before the image data as the code generation source is captured. That is, since the product that has been trapped on the glass member 11 at the time of decoding the product codes described in the variable X and the variable Xp is likely to be a different product although the product code is the same, the second determination section 283 is used. Determines that the two products are not identical (No in step S214). In this case, the output control section 284 outputs the product code described in the variable X to the information processing terminal 2 (step S212), and the main control section 281 stores the content of the variable Xp in the memory 26 in the variable X. The code is rewritten (step S213). Thereafter, the process returns to step S203 again.

  On the other hand, if all the series of timing times T are below the threshold value Ts, the image data that is the generation source of the product code described in the variable Xp is captured and then the product code described in the variable X is stored. There is a high possibility that the same product has been continuously crushed by the glass member 11 until the image data as the generation source is captured. In this case, the second determination section 283 determines that both products are the same (Yes in step S214). Thereafter, the process returns to step S203 again without outputting the product code by the output control section 284.

  Note that the processing according to the flowchart shown in FIG. 8 is continued until, for example, an end of barcode reading is instructed from the information processing terminal 2. The information processing terminal 2 uses the product code output from the barcode scanner 1 in a series of processes to perform accounting for the product indicated by each product code.

  As described above, the barcode scanner 1 in this embodiment measures the time when the decoder 23 cannot recognize the barcode from the image data by the timer 251 and compares the measured time T with the threshold value Ts. The identity of the product for which the product code has been newly read and the product for which the product code has been read immediately before is determined. Even in this case, the function for preventing double reading works only when the same product is deceived by the barcode scanner 1 as in the above embodiments. Collection is possible, and the operator is not burdened by this function.

(Fourth embodiment)
Next, a fourth embodiment will be described.
In this embodiment, an RFID (Radio Frequency Identification) tag attached to the operator's hand and a barcode scanner are used to identify the identity of a product for which a product code has been newly read and a product for which the product code has been read immediately before. 1 is different from the above-described embodiments in that the determination is performed using the RFID reader provided in FIG. The same portions as those in the above-described embodiments are denoted by the same reference numerals, and redundant description is performed only when necessary.

  FIG. 9 is a schematic diagram showing a usage state of the barcode scanner 1 in the present embodiment. Next to the barcode scanner 1 provided in the information processing terminal 2, an antenna 300 for transmitting and receiving radio waves with the RFID tag is provided. The antenna 300 has directivity in the direction facing the barcode scanner 1 and its communication range is adjusted to be slightly wider than the reading range 40.

  The operator of the barcode scanner 1 according to the present embodiment wears the product on the glass member 11 while wearing the wristband 302 to which the RFID tag 301 is attached on the wrist. The RFID tag 301 includes an IC in which tag information for identifying the RFID tag 301 is stored and a tag antenna for wireless communication with the antenna 300. When a radio wave for reading emitted from the antenna 300 is received by the tag antenna of the RFID tag 301, a response radio wave indicating tag information stored in the IC is emitted from the tag antenna.

  FIG. 10 is a block diagram showing a main configuration of the barcode scanner 1 in the present embodiment. In addition to the configuration described in the third embodiment, the barcode scanner 1 includes an RFID reader 252 that functions as detection means in the present embodiment. The antenna 300 is connected to the RFID reader 252.

  The RFID reader 252 modulates digital data for reading an RFID tag into a high frequency signal and supplies it to the antenna 300, and demodulates the high frequency signal output from the antenna 300 into digital data. The antenna 300 converts a high-frequency signal input from the RFID reader 252 into a radio wave and transmits it to the communication range. When receiving a response radio wave from the RFID tag 301, the antenna 300 converts the radio wave into a high-frequency signal and outputs it to the RFID reader 252. To do. The RFID reader 252 has a function of determining whether tag information is detected from the RFID tag 301 and notifying the control unit 28 of the result. This determination is made, for example, by storing tag information of the RFID tag 301 in advance in a ROM provided in the RFID reader 252 and comparing the tag information with demodulated digital data. That is, it is determined that the tag information is detected when the tag information stored in the ROM matches the demodulated digital data, and the tag information is not detected when the tag information does not match and when the digital data is not output. judge.

  The timer 251 in the present embodiment is controlled by the control unit 28 and measures the time from when the RFID reader 252 can no longer detect tag information from the RFID tag 301 until the next tag information is detected.

  Similarly to the third embodiment, the memory 26 stores the product code generated by the decoder 23, the time T counted by the timer 251 and the like, and the second determination section 283 determines whether or not both products are the same. As a determination criterion, the time T stored in the memory 26 and the threshold value Ts are used. That is, the second determination section 283 determines whether the time indicated by the threshold value Ts has been timed by the timer 251 and determines whether the two products are the same based on the result.

Next, the operation of the barcode scanner 1 will be described.
FIG. 11 is a flowchart for explaining the operation of the barcode scanner 1 in the present embodiment. The process shown in this flowchart is started in response to an instruction to start barcode reading from the information processing terminal 2, for example.

  In this process, first, the main control section 281 of the control unit 28 generates variables X and Xp in the memory 26 (step S301), and instructs the light source drive circuit 24 to start illumination (step S302). When receiving this instruction, the light source driving circuit 24 starts energizing the LED light sources 201 to 204 and turns on the LED light sources 201 to 204.

  After the illumination is started, the RFID reader 252 transmits a radio wave for reading from the antenna 300 (step S303), and determines whether tag information is detected from the RFID tag 301 (step S304). When the operator does not hesitate a product on the glass member 11, there is no RFID tag 301 within the communication range of the antenna 300. Accordingly, since no response radio wave is obtained from the RFID tag 301, tag information is not detected (No in step S304). In this case, the RFID reader 252 notifies the control unit 28 that tag information has not been detected. When the control unit 28 receives this notification, the main control section 281 instructs the timer 251 to start timing (step S305). When this command is received, the timer 251 continues the timing operation if it is in a timing operation, and starts the timing operation if it is stopped.

  On the other hand, when the operator is putting a product on the glass member 11, the RFID tag 301 is located within the communication range of the antenna 300. Therefore, since a response radio wave is obtained with respect to the radio wave for reading transmitted from the antenna 300, tag information is detected (Yes in step S304). In this case, the RFID reader 252 notifies the control unit 28 that tag information has been detected. When the control unit 28 receives this notification, the main control section 281 stores the time measured by the timer 251 in the memory 26 (step S306), and stops the timed operation of the timer 251 to reset the time measured T to zero. (Step S307).

  After the process of step S305 or step S307, the image sensor 22 photoelectrically converts the optical image formed by the lens 21 to generate image data, and outputs it to the decoder 23 (step S308).

  When receiving the image data from the image sensor 22, the decoder 23 tries to recognize the barcode from the image data, and if the barcode is recognized, tries to decode it (step S309). If the decoder 23 successfully decodes the barcode, the decoder 23 notifies the control unit 28 of the product code generated by the decoding.

  After trial of decoding by the decoder 23, the main control section 281 determines whether the decoding by the decoder 23 is successful (step S310). If the product code is not output from the decoder 23, the main control section 281 determines that decoding has failed (No in step S310). In this case, the processes of steps S303 to S309 are repeated. That is, the time count T is accumulated and stored in the memory 26 as many times as the processing in step S306 is executed until the decoding is successful. The time count T stored in the memory 26 is deleted immediately before the first step S303 is executed after successful decoding, for example.

  Eventually, when a product is picked up in an appropriate posture within the reading range 40, the barcode attached to the product is clearly reflected in the image data, and the barcode is decoded by the decoder 23. At this time, when the product code sent from the decoder 23 is received, the main control section 281 determines that the decoding has succeeded (Yes in step S310). At this time, the main control section 281 describes the product code received from the decoder 23 in the variable X formed in the memory 26 (step S311).

  Next, the first determination section 282 of the control unit 28 compares the variable X and the variable Xp to determine whether or not they match (step S312). If the first determination section 282 determines that the variable X and the variable Xp do not match (No in step S312), the output control section 284 of the control unit 28 outputs the product code described in the variable X to the information processing terminal 2. (Step S313). Further, the main control section 281 rewrites the contents of the variable Xp in the memory 26 with the product code described in the variable X (step S314). Thereafter, the process returns to step S303.

  On the other hand, when it is determined by the first determination section 282 that the variable X and the variable Xp match (Yes in step S312), the second determination section 283 changes to the image data that is the generation source of the product code described in the variable X. It is determined whether the displayed product is the same as the product displayed in the image data that is the generation source of the product code described in the variable Xp (step S315). This determination is performed after the image data that is the generation source of the product code described in the variable Xp is captured until the image data that is the generation source of the product code described in the variable X is captured. This is performed by comparing a series of measured time T stored in the above and a threshold value Ts.

  If even one of the series of measured times T exceeds the threshold value Ts, the image data that is the source of the product code described in the variable Xp is captured and then the product described in the variable X There is a high possibility that the product on the glass member 11 has been replaced before the image data as the code generation source is captured. That is, since the product that has been trapped on the glass member 11 at the time of decoding the product codes described in the variable X and the variable Xp is likely to be a different product although the product code is the same, the second determination section 283 is used. Determines that the two products are not identical (No in step S315). In this case, the output control section 284 outputs the product code described in the variable X to the information processing terminal 2 (step S313), and the main control section 281 stores the content of the variable Xp in the memory 26 in the variable X. The code is rewritten (step S314). Thereafter, the process returns to step S303 again.

  On the other hand, if all the series of timing times T are below the threshold value Ts, the image data that is the generation source of the product code described in the variable Xp is captured and then the product code described in the variable X is stored. There is a high possibility that the same product has been continuously crushed by the glass member 11 until the image data as the generation source is captured. In this case, the second determination section 283 determines that both products are the same (Yes in step S315). Thereafter, the process returns to step S303 again without outputting the product code by the output control section 284.

  Note that the processing according to the flowchart shown in FIG. 11 is continued until, for example, an end of barcode reading is instructed from the information processing terminal 2. The information processing terminal 2 uses the product code output from the barcode scanner 1 in a series of processes to perform accounting for the product indicated by each product code.

  As described above, the barcode scanner 1 according to the present embodiment measures the time when the RFID reader 252 cannot detect tag information from the RFID tag 301 by the timer 251 and compares the time T and the threshold Ts. Thus, the identity of the product for which the product code has been newly read and the product for which the product code has been read immediately before is determined. Even in this case, the function for preventing double reading works only when the same product is deceived by the barcode scanner 1 as in the above embodiments. Collection is possible, and the operator is not burdened by this function.

(Modification)
In addition, the structure disclosed in each said embodiment can be embodied by making various changes in the implementation stage. Examples of such modifications include the following.
(1) In each of the above embodiments, the barcode scanner 1 that reads a barcode attached to a product is illustrated. However, the configurations disclosed in the above embodiments may be applied to a barcode scanner used to read a barcode attached to an article other than a product. Further, the configuration disclosed in each of the above embodiments may be applied to a symbol code reader that reads a symbol code other than a barcode. As a symbol code other than the bar code, for example, there is a two-dimensional code such as a QR code (registered trademark).

(2) In each of the above embodiments, when it is determined that the product for which the product code is newly read and the product for which the product code is read immediately before are the same (Yes in steps S111, S214, and S315), The newly read product code is not output to the information processing terminal 2, and the product imaging and the barcode decoding are repeated. However, a configuration may be adopted in which an error is notified to the information processing terminal 2 when both products are determined to be the same, or the barcode scanner 1 itself notifies the error by turning off or blinking the light source 20.

(3) In each of the above embodiments, the case where the identity of the product is determined based on the average luminance Bave measured by the luminance measuring unit 25 and the time measured T measured by the timer 251 is exemplified. However, a configuration may be adopted in which the identity of a product is determined using other information collected after a certain product code is read and before the next product code is read.
For example, a marker recognizing unit that attaches a marker of a predetermined shape to the operator's hand and recognizes the marker from the image data captured by the image sensor 22 is provided in the barcode scanner 1, and after a certain product code is read, Until the product code is read, the timer recognizes the time during which the marker cannot be recognized by the marker recognition means. When the time measured by the timer falls below a predetermined threshold, it is determined that the product for which the product code is newly read and the product for which the product code is read immediately before are the same. Even if it does in this way, there exists an effect similar to the said each embodiment.

  In addition, some constituent elements may be deleted from all the constituent elements shown in the respective embodiments, or constituent elements over different embodiments may be appropriately combined.

  DESCRIPTION OF SYMBOLS 1 ... Barcode scanner, 2 ... Information processing terminal, 20 ... Light source, 21 ... Lens, 22 ... Image sensor, 23 ... Decoder, 24 ... Light source drive circuit, 25 ... Luminance measuring part, 26 ... Memory, 27 ... Connection interface, DESCRIPTION OF SYMBOLS 28 ... Control part, 251 ... Timer, 252 ... RFID reader, 281 ... Main control section, 282 ... Judgment section, 283 ... Judgment section, 284 ... Output control section, 300 ... Antenna

Claims (6)

Imaging means for imaging an article with a symbol code representing code information;
A decoding unit that recognizes a symbol code included in an image captured by the imaging unit and decodes the recognized symbol code to generate code information;
Whether the first code information, which is code information newly generated by the decoding means, matches the second code information, which is code information generated by the decoding means immediately before the first code information is generated First determination means for determining
When the first determination unit determines that the first code information and the second code information match, the first code information generation source is captured after an image that is the generation source of the second code information is captured. Based on the image picked up by the image pickup means until the image to be obtained is picked up, an article with a symbol code representing the first code information and a symbol code representing the second code information are attached. A second determination means for determining whether the received article is the same;
When the first determination means determines that the first code information and the second code information do not match, and the article to which the symbol code representing the first code information is attached by the second determination means and the first code information Output control means for outputting the first code information when it is determined that the article with the symbol code representing the two-code information is not the same;
A symbol code reading device comprising: Further comprising a luminance measuring means for measuring the average luminance of the image captured by the imaging means;
The second determination means is an image picked up by the image pickup means between the time when the image that is the generation source of the second code information is captured and the time that the image that is the generation source of the first code information is captured. Or an article to which a symbol code representing the first code information is attached when at least one of the average brightness measured by the brightness measuring means for a plurality of images falls below a predetermined threshold; and the second 2. The symbol code reader according to claim 1, wherein it is determined that the article to which the symbol code representing the code information is attached is not the same.   3. The symbol code reading according to claim 2, wherein the threshold value is calculated by multiplying an average luminance measured by the luminance measuring unit with respect to an image as a generation source of the second code information by a predetermined ratio. apparatus. A timing unit that counts the time from when the decoding unit cannot recognize the presence of the symbol code from the image captured by the imaging unit until the next time the symbol code is recognized;
The second determination unit is predetermined by the time measuring unit between the time when the image as the generation source of the second code information is captured and the time when the image as the generation source of the first code information is captured. When the time is counted, it is determined that the article attached with the symbol code representing the first code information is not the same as the article attached with the symbol code representing the second code information. The symbol code reader according to claim 1. Imaging means for imaging an article with a symbol code representing code information;
Decoding means for decoding the symbol code included in the image imaged by the imaging means to generate code information;
Detecting means for detecting the tag information by wireless communication from a wireless tag storing the tag information;
Time measuring means for measuring the time from when the detecting means can no longer detect the tag information until the tag information is detected next;
Whether the first code information, which is code information newly generated by the decoding means, matches the second code information, which is code information generated by the decoding means immediately before the first code information is generated First determination means for determining
It is determined whether a predetermined time is counted by the time measuring unit between the time when the image as the generation source of the second code information is captured and the time when the image as the generation source of the first code information is captured. A second determination means;
When the first determination unit determines that the first code information and the second code information do not match, and the first determination unit matches the first code information and the second code information Output control means for outputting the first code information when it is determined and the second determination means determines that a predetermined time is being measured;
A symbol code reading device comprising: A symbol code reader comprising: an imaging unit that images an article with a symbol code representing code information; and a decoding unit that decodes a symbol code included in an image captured by the imaging unit to generate code information A control program for the device,
In the symbol code reader,
Does the first code information, which is code information newly generated by the decoding unit, match the second code information, which is code information generated by the decoding unit immediately before the first code information is generated? A first determination function for determining
When it is determined by the first determination function that the first code information and the second code information match, the first code information generation source is captured after an image that is the generation source of the second code information is captured. Based on the image picked up by the image pickup unit until the image to be taken is picked up, an article attached with a symbol code representing the first code information and a symbol code representing the second code information are attached. A second determination function for determining whether the received article is the same;
When the first determination function determines that the first code information and the second code information do not match, and the article to which the symbol code representing the first code information is attached by the second determination function and the first code information An output control function for outputting the first code information when it is determined that the article with the symbol code representing the two-code information is not the same;
Control program to realize.

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