JP5644538B2 - Optical information reader - Google Patents

Description

  The present invention relates to an optical information reader that optically reads a one-dimensional code such as a barcode, and more particularly to an optical information reader that can read a one-dimensional code obtained by adding an add-on barcode to a main barcode. .

  For example, barcode recognition technology is used for various purposes such as retail store checkout operations, inventory management, and production line process management. Usually, WPC (World Product Code) bar codes such as EAN-13, EAN-8, UPC-A, UPC-E, etc. are applied to products sold in retail stores as one-dimensional codes. Many. These WPC barcodes may display a barcode with an add-on barcode added to the right side of the main barcode. In order to decode such a barcode with an add-on barcode, a function for decoding an add-on barcode is required in addition to a function for decoding a normal barcode.

  WPC barcodes always have the same barcode structure regardless of whether or not add-on barcodes are added according to the standard, so add-on barcodes are added only by decoding the barcode on the main side. It cannot be determined whether or not there is. Therefore, in the conventional barcode reader, after the barcode on the main side is decoded, the barcode on the add-on side is always detected for a certain time. However, the method that always detects add-on barcodes for a certain period of time after decoding the main-side barcode detects unnecessary add-on barcodes even when no add-on barcodes are added. Therefore, the reading process takes time.

  For this reason, in the barcode reader disclosed in Patent Document 1 below, when the main barcode can be decoded, the add-on barcode is captured when a part of the add-on barcode is imaged together with the main barcode. Wait for the code to be read. As a result, the reading-out of the add-on barcode is eliminated, and the reading result is output immediately for the barcode to which the add-on barcode is not added. This shortens the time required for the reading process.

  Further, in the barcode reader disclosed in the following Patent Document 2, it is determined whether or not an add-on barcode is added to the main barcode, and when an add-on barcode is added to the read image, The decoding result of main barcode and add-on barcode is output. If an add-on barcode is not added to the scanned image, it is determined whether or not an operation to bring the barcode reader closer to the barcode is performed, and an operation to bring the barcode reader closer is performed. Otherwise, only the main bar code decoding result is output. As long as the operation for bringing the barcode reader closer is performed, it is continued to determine whether the add-on barcode is added. This prevents an add-on barcode from being overwritten due to the operation of the barcode reader.

JP 2003-022416 A JP 2009-193332 A

  By the way, since the reflected light from the one-dimensional code is received by the light receiving sensor through the reading opening, when the line sensor in which the light receiving elements are arranged one-dimensionally is adopted as the light receiving sensor, the reading opening is a bar code. When the barcode is read while being tilted with respect to the arrangement direction, the angle between the reading line by the light receiving sensor and the arrangement direction of the barcode may increase. In this case, if a bar code or pattern different from the add-on bar code is displayed on the reading line even if it is shifted from the position where the add-on bar code is originally arranged with respect to the first bar code read, There is a problem that an add-on barcode is erroneously determined based on a different barcode or the like.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an optical information reading apparatus that can improve the accuracy of determination regarding the presence or absence of an add-on barcode. is there.

In order to achieve the above object, in the optical information reading apparatus according to claim 1, the main bar code including a plurality of dark color patterns and light color patterns arranged in the vicinity of the main bar code is provided. An optical information reader that optically reads an added add-on barcode as a one-dimensional code, and receives light reflected from the one-dimensional code along a predetermined reading line; and A decoding means for decoding a one-dimensional code based on a light reception signal output from the first code, and when the light reception signal includes two one-dimensional codes, the one-dimensional code positioned first in the reading direction is a first code , when the one-dimensional code is located in the second reading direction and a second code, the angle between the alignment direction and the reading line of the first code, the distance sensor Calculating means for calculating from a separation distance from the light receiving means to the first code measured by using and a width value of the first code obtained from the light receiving signal; the first code and the second code; The interval in the direction along the reading line is equal to or greater than a threshold at which the second code can be regarded as the add-on barcode, and the calculated value by the calculation means is equal to or less than a threshold at which the second code can be regarded as the add-on barcode. A determination unit that determines that the second code is the add-on barcode in a certain case, and the decoding unit determines that the second code is the add-on barcode by the determination unit The first code is the main bar code, and the second code is the add-on bar code for decoding. To.

According to the first aspect of the present invention, when the light receiving signal includes two one-dimensional codes, the calculating means measures the angle between the arrangement direction of the first code and the reading line using the distance sensor. To the first code and the width value of the first code obtained from the received light signal . The interval between the first code and the second code in the direction along the reading line is equal to or greater than a threshold at which the second code can be regarded as an add-on barcode, and the value calculated by the calculating means regards the second code as an add-on barcode. If it is equal to or less than the threshold value to be obtained, the determination means determines that the second code is an add-on barcode. When the determination unit determines that the second code is an add-on barcode, the decoding unit performs a decoding process using the first code as a main barcode and the second code as an add-on barcode.

When the first code or the like is optically read in a state where the reading port of the apparatus into which the reflected light from the first code or the like is taken in is inclined with respect to the arrangement direction of the first code, the arrangement direction of the first code And the reading line become relatively large . In their this, depending on the angles between the line read to the array direction of the first code, that the second code is determined if an add barcode reading opening of the device is arranged in the first code Even when the first code or the like is read while being tilted with respect to the direction, the probability of erroneous determination that there is an add-on barcode can be reduced.
Therefore, even when reading is performed in a state where the reading port is inclined with respect to the arrangement direction of the first code, it is possible to improve the accuracy of the determination regarding the presence or absence of the add-on barcode.

It is sectional drawing which shows the structure of the optical information reader which concerns on this embodiment. It is a block diagram which shows the electrical structure of the optical information reader of FIG. It is a figure which shows an example of a WPC system barcode with an add-on barcode. It is explanatory drawing which illustrates reading-out of the add-on barcode which may occur during operation of an optical information reader. It is explanatory drawing which illustrates the inclination angle of the reading line by a line sensor, and the arrangement direction of barcode. FIG. 6A is an explanatory diagram showing a light reception waveform corresponding to the tilt angle of FIG. 5A, and FIG. 6B is an explanatory diagram showing a light reception waveform when the tilt angle is 0 °. is there. 3 is a part of a flowchart illustrating a flow of a reading process performed by a control circuit in FIG. 2. 3 is a part of a flowchart illustrating a flow of a reading process performed by a control circuit in FIG. 2. 3 is a part of a flowchart illustrating a flow of a reading process performed by a control circuit in FIG. 2. It is a flowchart which shows the subroutine process in the judgment process (1) in operation by depth. It is a flowchart which shows the subroutine process in the judgment process (2) in operation at a position. It is a flowchart which shows the subroutine process in an add-on barcode presence determination process. It is a figure which shows an example of a guard bar pattern. It is a figure which shows the other example of a guard bar pattern. It is explanatory drawing of the judgment process (1) in operation by depth. It is explanatory drawing of the judgment process (2) in operation by a position. FIG. 17A is an explanatory diagram for explaining the angle threshold, and FIG. 17B is an explanatory diagram for explaining the perpendicular length threshold. FIG. 18A is an explanatory diagram for explaining a state where the tilt angle is equal to or smaller than the angle threshold, and FIG. 18B is a diagram for explaining a state where the perpendicular length is equal to or smaller than a predetermined perpendicular length threshold. It is explanatory drawing. It is explanatory drawing for demonstrating the state which an inclination angle is not below an angle threshold value, and a perpendicular length is not below a predetermined perpendicular length threshold value. FIG. 20A is a diagram illustrating a state in which a part of the add-on barcode is removed from the reading port, and FIG. 20B is a diagram illustrating a state in which the bar at the left end of the second code is abnormally thick. FIG. 20C is a diagram showing a state where the first code and the second code are too far apart.

Hereinafter, an embodiment of an optical information reading apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a configuration of an optical information reading apparatus 10 according to the present embodiment.
As shown in FIG. 1, the optical information reader 10 optically reads a one-dimensional code such as a bar code configured by arranging a plurality of black bars (dark color patterns) and white bars (bright color patterns). The apparatus includes an operation unit 12 that also serves as a grip, for example, a liquid crystal display 14 made of liquid crystal. For example, the operation unit 12 is provided with a plurality of key switches 16, and the operation contents are instructed by these key switches 16. In addition to the key switch 16, the operation unit 12 is provided with a trigger switch 18 for instructing the start of reading.

  A printed wiring board 20 is fixed in a housing 60 of the optical information reading apparatus 10, and key switches 16 are mounted in a matrix on one surface of the printed wiring board 20. On the other surface of the printed wiring board 20, a line sensor 32 is mounted upright as a light receiving means configured by linearly arranging CCDs as light receiving elements.

  An optical system unit 30 is disposed in an opening (hereinafter referred to as a reading port 62) formed at the front end of the housing 60, and is reflected in a position on the optical axis of the optical system unit 30 in the housing 60. The mirror 34 is disposed, and the line sensor 32 is positioned on the optical axis bent by the reflecting mirror 34. Reflected light from the detection target is taken in through the reading port 62 and is imaged and received by the line sensor 32 via the optical system unit 30 and the reflecting mirror 34.

  A hole 22a is formed in the center of the printed wiring board 22 in the vicinity of the reading port 62, and a plurality of illumination LEDs 38 are mounted around the hole 22a. A lens unit 36 is mounted in the hole 22 a formed in the printed wiring board 22. This lens unit 36 is formed integrally with an imaging lens 36a for condensing the reflected light from the object to be detected and a condensing lens 36b for projecting the light from the illumination LED 38 to the front. .

Next, the circuit configuration of the optical information reader 10 will be described with reference to the block diagram of FIG.
As shown in FIG. 2, the optical information reader 10 contains a microcomputer (hereinafter referred to as “microcomputer”) system such as a memory 35, a control circuit 40, a key switch 16, a trigger switch 18, and a liquid crystal display 14. ing.

  The microcomputer system includes an amplification circuit 31, an A / D conversion circuit 33, a memory 35, a control circuit 40, a key switch 16, a trigger switch 18, an LED 43, a buzzer 44, a liquid crystal display 14, a communication interface 48, and the like. As the name suggests, this microcomputer system is composed mainly of a control circuit 40 and a memory 35 that can function as a microcomputer (information processing device), and receives a received light signal (image signal) from the optical system in terms of hardware and The signal can be processed by software. The control circuit 40 also performs control related to the entire system of the optical information reader 10.

  The light reception signal (analog signal) output from the line sensor 32 of the optical system is amplified by a predetermined gain by being input to the amplifier circuit 31, and then input from the analog signal when input to the A / D conversion circuit 33. Converted into a digital signal. Then, the digitized light reception signal, that is, the light reception data is input to the control circuit 40.

  The control circuit 40 is a microcomputer that can control the entire optical information reading apparatus 10 and includes a CPU, a system bus, an input / output interface, and the like. The control circuit 40 can constitute an information processing apparatus together with the memory 35 and has an information processing function. . The control circuit 40 is configured to be connectable to various input / output devices (peripheral devices) via a built-in input / output interface. In this embodiment, the key switch 16, the trigger switch 18, the LED 43, A buzzer 44, a liquid crystal display 14, a communication interface 48, and the like are connected. The control circuit 40 is configured to output the result of reading the barcode to the host device (for example, a computer) (not shown) via the communication interface 48.

Next, the configuration of a barcode to be read in this embodiment will be described with reference to FIG. FIG. 3 is a diagram showing an example of a WPC barcode with an add-on barcode.
In FIG. 3, the barcode located in the first reading direction (left side in FIG. 3) is referred to as a main barcode Bm, and the vicinity of the main barcode Bm (as shown in FIG. 3) located in the second reading direction (right side in FIG. 3). The bar code added to the right side at 3 is called an add-on bar code Ba. The main bar code Bm is configured such that guard bar patterns exist on both the left and right sides thereof, and the add-on bar code Ba is configured so that the guard bar pattern exists only on the left side thereof.

  In the example of FIG. 3, the guard bar pattern exists on both the left and right sides of the main barcode Bm, and includes two black bars that protrude long downward on the left and right sides, and one white bar sandwiched between them. It consists of a total of 3 bars. For the add-on barcode Ba, the guard bar pattern exists only on the left side, and is configured by a total of three bars, two black bars on the left side and one white bar sandwiched between them. In the present embodiment, a blank portion (space) between black bars is regarded as a white bar and counted as one bar.

  In the main bar code Bm of FIG. 3, the last character including the white bar adjacent to the right guard bar pattern from the right side to the fourth black bar from the white bar to the left is the final character. Further, in the add-on barcode Ba, the first character is the first black bar from the white bar to the right, including the white bar adjacent to the left guard bar pattern from the left side.

  In the present embodiment, after decoding a predetermined bar code, the bar code is used as a first code, the width of a certain number of bars is calculated from the right end to the left, and a reference value is calculated by a preset formula. Then, the width of a certain number of bars is calculated from the left end of the add-on side barcode (hereinafter referred to as the second code) from the left end to the right, and the comparison value is calculated by a preset equation. When the comparison value is within a predetermined range with respect to the reference value, it is determined that the first code is the main barcode Bm, and the add-on barcode Ba, which is the second code, is added to the main barcode Bm. To do. For this reason, if there is a striped pattern similar to the last character of the first code at a position where the first character of the add-on barcode is accidentally present, the probability of determining this as an add-on barcode is low. When no add-on barcode exists, the time required to transfer the decoded data can be shortened.

  Furthermore, in the present embodiment, the number of bars determined for determining the reference value and the number of bars determined for determining the comparison value are the arrangement (arrangement configuration) of the main barcode Bm and the add-on barcode Ba. Based on the above, the difference between the reference value obtained by applying the width of the fixed number of bars of the first code to the equation and the comparison value obtained by applying the width of the fixed number of bars of the second code to the equation is the maximum. The number of bars is equal to or less than the width of the small width (one module) bar. The fixed number of bars for obtaining the reference value and the comparison value will be specifically described below.

A. The guard bar pattern is EAN-8, EAN-13, UPC-A composed of three bars of black, white and black, and the case where the add-on barcode Ba is 2 digits and 5 digits is as follows. This is illustrated in
(1) Add-on barcode with 2 digits
(i) Both the main bar code Bm and the add-on bar code Ba up to the third (between the guard bar and one character)
(ii) Both the main barcode Bm and the add-on barcode Ba up to the seventh (between the first character and the second character) (2) In the case of a five-digit add-on barcode
(i) Both the main bar code Bm and the add-on bar code Ba up to the third (between the guard bar and one character)
(ii) Both the main barcode Bm and the add-on barcode Ba up to the seventh (between the first character and the second character)
(iii) Up to the 19th main barcode Bm and the 21st add-on barcode Ba

B. The guard bar pattern is a UPC-E composed of six bars of black, white, black, white, black, white, and the case where the add-on barcode Ba is 2 digits and 5 digits is illustrated below To do.
(1) Add-on barcode with 2 digits
(i) Up to 3rd to 5th main bar code Bm and up to 3rd add-on bar code Ba (between the guard bar portion and one character). In particular, when the main bar code Bm up to the fourth bar is adopted, the total width on the standard is the same as the add-on bar code Ba.
(ii) Up to 9th main barcode Bm and 7th add-on barcode Ba (between 1 character and 2 characters) (2) 5-digit add-on barcode
(i) Main bar code Bm up to 3rd to 5th and add-on bar code Ba up to 3rd (between guard bar part and 1 character)
(ii) Up to 9th main bar code Bm and 7th add-on bar code Ba (between 1 character and 2 characters)
(iii) Both the main bar code Bm and the add-on bar code Ba up to the 13th bar (between the guard bar and one character)
(iv) Up to the 17th main barcode Bm and the 15th add-on barcode Ba, but the 15th add-on barcode Ba is subtracted.

  If the number of bars for obtaining the reference value and the comparison value is set as described above, the reference value obtained from the first code and the comparison value obtained from the second code are less than the minimum width (one module) of the bar. The reference values and the comparison values can be compared with high accuracy by almost matching the differences.

  And in this embodiment, the comparison value calculated | required according to the value which added the width | variety of the number of bars below a fixed number toward the right from the left end of the 2nd code exceeded the predetermined range with respect to the reference value. At this time, it is determined that no add-on barcode is added. According to this configuration, when only a part of the bar code on the add-on side (similar to the barcode) enters the reading port 62 of the optical information reader 10, an abnormally wide bar (similar to a part similar to that) ) Exists, it is determined that the barcode is not an add-on barcode. Therefore, a non-add-on barcode can be quickly determined not to be an add-on barcode.

FIG. 4 is an explanatory view exemplifying the reading-out of the add-on barcode Ba that may occur during the operation of the optical information reader 10, and FIG. 4 (A) is a state during the operation of bringing the reading port 62 closer to the barcode. FIG. 4B shows a state during the operation of moving the reading port 62 in the horizontal direction along the barcode.
In the present embodiment, even when it is determined that there is no add-on barcode, it is further determined whether the add-on barcode is not missed. That is, as shown in FIG. 4A, only the main bar code Bm of the bar code is being performed during the operation of moving the reading port 62 of the optical information reading apparatus 10 close to the bar code from a distant position. At this time, the add-on barcode Ba may not be included in the light reception signal corresponding to the reception of the reflected light from the main barcode Bm. In this case, the add-on barcode Ba is missed only by the above-described processing. As shown in FIG. 4B, an operator unfamiliar with the operation of the optical information reading apparatus 10 moves the reading port 62 along the bar code in the horizontal direction (arrangement direction of each bar). When the code reading is attempted, only the main bar code Bm may enter the reading port 62. In this case, the add-on barcode Ba is missed only by the above-described processing. Therefore, in order to prevent the add-on bar code from being missed as described above, even when it is determined from the received light signal for decoding the main bar code Bm that there is no add-on bar code Ba, the optical information reader 10 further includes Judges whether the add-on barcode has been missed by the operation in the proximity direction or horizontal direction.

  FIG. 5 is an explanatory diagram illustrating the inclination angle θ between the reading line L1 and the barcode arrangement direction L2 by the line sensor 32, and FIG. 5A shows a state where the add-on barcode Ba is added, FIG. 5B shows a state where the add-on barcode Ba is not added. 6A is an explanatory diagram showing a light reception waveform corresponding to the inclination angle θ of FIG. 5A, and FIG. 6B is an illustration showing a light reception waveform when the inclination angle θ is 0 °. FIG.

  Furthermore, in this embodiment, even when it is assumed (determined) that there is an add-on barcode, it is further determined whether or not the assumption is incorrect. Usually, since the operator reads the reading port 62 along the barcode, as shown in FIG. 5A, the reading line L1 which is a line received in one dimension by the line sensor 32 and the barcode. The angle with respect to the arrangement direction L2 (hereinafter referred to as an inclination angle θ) becomes small. At this time, the line sensor 32 outputs a light reception signal having a light reception waveform as illustrated in FIG. Here, when the inclination angle θ is 0 °, a light reception signal having a light reception waveform as illustrated in FIG. 6B is output from the line sensor 32. As can be seen from FIGS. 6A and 6B, the longer the inclination angle θ, the longer the widths of the first code and the second code occupied in the received light waveform.

  However, when the barcode is read with the reading port 62 inclined with respect to the barcode arrangement direction L2, the inclination angle θ between the reading line L1 and the barcode arrangement direction L2 by the line sensor 32 becomes large. There is. In this case, as illustrated in FIG. 5B, even if the barcode or pattern different from the add-on barcode is shifted from the position where the add-on barcode is originally arranged with respect to the barcode read first, This is because, if displayed on the reading line L1, there is a possibility of erroneous determination that an add-on barcode exists based on this different barcode or the like.

  Therefore, in order to prevent the erroneous determination of the add-on barcode as described above, even when it is assumed that there is an add-on barcode Ba from the light reception signal for decoding the main barcode Bm, In consideration of the inclination of the reading port 62, whether or not there is an add-on barcode is determined in detail. In this way, by reducing the probability of erroneously determining that there is an add-on barcode, it is possible to shorten the time required to transfer the decoded data when no add-on barcode exists.

  Next, reading processing in the control circuit 40 when reading a barcode will be described with reference to the flowcharts shown in FIGS. 7 to 9 are flowcharts illustrating the flow of reading processing performed by the control circuit 40 of FIG. FIG. 10 is a flowchart showing a subroutine process in the determination process (1) during the operation at the depth. FIG. 11 is a flowchart showing a subroutine process in the determination process (2) during operation at a position. FIG. 12 is a flowchart showing a subroutine process in the add-on barcode presence / absence determination process. In the following description, the first code, which is a bar code located on the main side to be read, is a WPC bar code and includes four types of EAN-13, EAN-8, UPC-A, and UPC-E. Suppose that it is either.

  The reading port 62 is applied to the bar code to be read and the reading operation is started by the trigger switch 18. Then, the illumination LED 38 is turned on and projected onto a barcode (label), and the reflected light is imaged on the line sensor 32 by the imaging lens 36a (S12 shown in FIG. 7). Then, the control circuit 40 binarizes the received light signal from the bar code received by the line sensor 32 and stores it in the RAM of the memory 35 (S14), and then the bar located on the main side based on the binarized data. The first code, which is a code, is decoded and stored in the RAM in the memory 35 (S16). Note that the control circuit 40 that executes S16 and S68 described later may correspond to an example of a “decoding unit” recited in the claims.

  Next, the control circuit 40 determines the type of the decoded first code (S18), and when the number of guard bars is 3, that is, any of UPC-A, EAN-8, and EAN-13 In this case, the widths B1 to B7 of each bar from the right end to the seventh are obtained, and the reference value X is obtained by the following preset equation (1) (S20). When the number of guard bars is 6, that is, UPC-E, the widths B1 to B10 of each bar from the right end to the tenth bar are obtained, and the reference value X is determined by the following (2 ) (S22).

X = B7 + B6 + B5 + B4 + B3 + B2 + B2 + B1 (1)
X = B10 + B9 + B8 + B7 + B6 + B5 + B4 + B3 + B2-B1 (2)
In the above formulas (1) and (2), the subscript numbers attached to B indicate the order of arrangement from the right end, 1 is the right end bar, 2, 3, 3,... The third, third, ... bars are shown.

  The meanings of these formulas (1) and (2) are as follows. First, in this embodiment, whether or not an add-on barcode is added is determined by calculating the width of a certain number of bars of the first code and applying this to a preset equation to calculate the reference value X. At the same time, the width of a predetermined number of bars of the second code, which is the barcode on the add-on side, is obtained and applied to a preset equation to calculate the comparison value Z. Then, whether or not an add-on barcode is added is determined depending on whether or not the comparison value Z is within a certain range with respect to the reference value X, for example, 80% to 120% of the reference value X. .

FIG. 13 is a diagram illustrating an example of a guard bar pattern. FIG. 14 is a diagram illustrating another example of the guard bar pattern.
In the barcode, a plurality of types of bars having different widths are used, and the minimum width among them is called one module. As illustrated in FIGS. 13 and 14, in the add-on barcode Ba, the total value of the bar widths from the left end to the seventh (guard bar portion and first character portion) is determined to be 11 modules. .

  On the other hand, in any of UPC-A, EAN-8, and EAN-13 in which the guard bar pattern of the main bar code Bm is composed of three bars, as shown in FIG. The seven bars are set to have a total width of 10 modules, and the width of each bar of the guard bar pattern is set to 1 module. For this reason, by summing the widths of the seven bars and further adding the width of one guard bar (for example, the second bar from the right end), which is one module width, as in the above equation (1), A width of 11 modules can be obtained as the reference value X.

  In the UPC-E in which the guard bar pattern of the main barcode Bm is composed of 6 bars, as shown in FIG. 14, the guard bar pattern and the final character are composed of a total of 10 bars. The total bar width is set to 13 modules, and the width of each bar of the guard bar pattern is set to 1 module. Therefore, the sum of the widths of the 10 bars and subtracting twice the width of one guard bar (for example, the rightmost bar), which is one module width, as in equation (2) above, As a value X, a width of 11 modules can be obtained.

  From the above, by comparing the comparison value Z, which is the added value of the width of the second bar from the left end of the second code, with the reference value X, it is possible to determine whether or not the add-on barcode Ba is added. .

  After calculating the value of X as described above, the control circuit 40 calculates the gap width G existing between the first code and the second code (S24), and calculates the gap width G and the reference value X. In comparison, it is determined whether or not the gap width G is within an allowable range determined to be within 120% (approximately 13.2 modules) of the reference value X (S26).

  When the add-on barcode is not added, the line sensor 32 reads the right side of the first code as white, so the control circuit 40 gaps the wide white portion on the right side of the first code (up to the right end of the reading port 62). And the width is calculated.

  If the gap width G is out of the allowable range, the control circuit 40 determines S26: No and determines that no add-on barcode is added (S76 shown in FIG. 9). Then, after determining whether or not the optical information reading apparatus 10 is being operated after S78, which will be described later, if it is determined that it is not in operation, the decoded data of the first code is transferred to the host device (S86). Become.

  When the gap width G is within the allowable range, the control circuit 40 determines S26: Yes, and then determines whether or not the first bar exists on the add-on side (S32). When the first bar does not exist, the control circuit 40 becomes S32: No, and executes the above S76 and subsequent steps in order.

  If the first bar exists, the control circuit 40 sets S32: Yes, sets the add-on side bar width addition value Y to 0 (S34), and adds Y to the first bar width b1. (S36). Next, the control circuit 40 determines whether or not the second bar exists on the add-on side (S38 shown in FIG. 8), and if it exists, the width of the second bar is added to the bar width addition value Y. b2 is added (S40). Thereafter, the existence of the third and subsequent bars up to the seventh is sequentially judged (S42, 46, 52, 56, 60). If any of the bars is present, the widths of the bars are sequentially accumulated (S44, 50, 54). 58, 62). Then, the addition value Y (comparison value Z) of the width of up to the seventh bar is compared with the reference value X, and is the addition value Y within an allowable range determined as 80% to 120% of the reference value X? It is determined whether or not (S64 shown in FIG. 9).

  If the added value Y of the widths of the seven bars is out of the allowable range (S64: No), the control circuit 40 determines that it is not an add-on barcode (S76). Then, if it is determined that the optical information reader 10 is being operated in S78 and later, and if it is determined that the optical information reader 10 is not being operated, the decoded data of the first code is transferred to the host device (S86). Become an end.

  On the other hand, when it is determined in the step of determining whether or not the second and subsequent bars are present (S38, S42, S46, S52, S56, S60: No), S72 in FIG. Migrate to Subsequently, the control circuit 40 determines whether or not the added value Y is 120% or less of the reference value X. If the added value Y exceeds 120% of X (S72: No), the process proceeds to S76 described above. It is determined that it is not an add-on barcode. Then, when it is determined that the optical information reader 10 is being operated after S78, which will be described later, and it is determined that the optical information reader 10 is not being operated, the decoded data of the first code is transferred (S86), and the process is ended. .

  If the added value Y of the bar width is within 120% of the reference value X (S72: Yes), the control circuit 40 proceeds to S74, where the buzzer 44 is sounded and the end and Become.

Subsequently, after it is determined in S76 that there is no add-on barcode, only the main barcode Bm is decoded while the reading port 62 is brought close to the barcode as described above with reference to FIG. Judge whether there is any. For this determination, first, the bar width value of the reading line 1 mm of the line sensor 32 is calculated (S78). Here, W is a measured value of the bar width constituting the first code shown in FIG. 15A, Wo is a label width assumed to be 1.0 times the size, and is calculated by the equation (3).
Bar width value of 1 mm reading line = W / Wo (3)

Here, the dimension of 1.0 times means that the standard value is used without being reduced and enlarged, and when the standard value is reduced to 0.8 times, it is called the dimension of 0.8 times. For example, in the case of EAN-13 / UPC-A with a size of 1.0 times, the equation (4) is obtained at 34.1 mm. It is 22.1 mm for EAN-8 and 18.0 mm for UPC-E.
Bar width value of 1 mm reading line = W / 34.1 mm (4)

In the present embodiment, for example, the following correspondence relationship between the reading depth (distance from the reading port 62 to the barcode) and the bar width value of the reading line 1 mm is as follows: Depth data [Depth and bar width relationship table] W100_? ] Is held in the memory 35.
Distance 00 mm: Bar width of reading line 1 mm: 511 (value measured by sensor output waveform)
Distance 10 mm: Bar width of reading line 1 mm: 456 (value measured by sensor output waveform)
Distance 20 mm: Bar width of reading line 1 mm: 421 (value measured by sensor output waveform)

  When the bar width value of the reading line 1 mm is calculated as described above, it is determined based on this calculated value whether or not an operation for bringing the optical information reader 10 close to the barcode is being performed (S100). The process in the determination process (1) during the operation at the depth of S100 will be described with reference to FIG. 10 showing a subroutine of the process. The reading depth may be set as a separation distance from the line sensor 32 to the first code.

  First, based on the bar width value of the reading line of 1 mm calculated in S78, the depth data of the bar width value of the reading line of 1 mm and the taking depth held in the memory 35 [depth-to-bar width relationship table W100_? ] To depth [H? ] Is obtained (S102). Then, it is determined whether the operation has just started (first decoding of the first code) (S104). When the depth H is obtained only once (S104: Yes), it is impossible to determine whether the operation in the proximity direction is being performed. Therefore, the operation start is registered (S114), and the distance obtained in S102 above. [H? ] Is backed up as a distance [H_B] in the memory (S116), the current time and the number of times of decoding are initialized (S118), and the first decoding is in progress because it is unknown whether or not the operation is in progress. And determining that there is no add-on barcode in S76 of FIG. 9 (S120).

  Here, in the case of the second and subsequent decoding (S104: No), it is determined whether a certain time (or a certain number of times of decoding) has elapsed since the previous comparison (S106). That is, since decoding is repeated in a short cycle, the depth [H? ] Cannot be determined accurately, and until a predetermined time has elapsed (S106: No), the process proceeds to S120, and the determination of no add-on barcode is invalidated. On the other hand, if a certain time has elapsed (or a certain number of decoding repetitions) since the previous comparison (S106: Yes), the current depth [H? ] Is subtracted from the previous depth [H_B] to obtain the moving distance (S108). Then, it is determined whether the moving distance (absolute value) is smaller than a predetermined threshold ZZ (S110). Here, the absolute value is used as the movement distance because it is determined that the optical information reader 10 is being operated both when the optical information reader 10 is moved closer to the barcode and when it is moved away from the barcode. Here, when the movement distance (absolute value) is larger than the predetermined threshold ZZ (S110: No), the optical information reader 10 is being operated toward the bar code or in the direction away from it, so that the process proceeds to S116. The process proceeds to S116 and S118, and the determination of no add-on barcode is invalidated (S120). On the other hand, when the movement distance (absolute value) is smaller than the predetermined threshold ZZ (S110: Yes), it is determined that the vertical operation on the optical information reader 10 is completed (or not operated) (S112).

Here, the process in the determination process (1) during the operation at the depth will be specifically described with reference to FIG.
Depth P1 shown in FIG. 15B indicates a position (depth) where the optical bar code is successfully decoded by moving the optical information reader 10 closer to the bar code. The depth P2 indicates the position (depth) at which the main barcode was successfully decoded after the lapse of the predetermined time in S106 described above. Here, when the difference between the depth P1 and the depth P2 is larger than the predetermined threshold ZZ, the determination of no add-on barcode is invalid, for example, decoding of the main barcode and the add-on barcode at the depth P3. Until decoding is successful, the decoding result output to the computer is waited.

  After the determination process (1) during operation at the depth (proximity, away direction) in S100, it is determined whether the operation is in S80 in FIG. If it is determined that the operation in the depth direction is being performed (S80: Yes), the buzzer 44 sounds and the LED 43 is lit to notify the operator that the operation is in progress, and waits until the add-on barcode can be read. Let them know that they are doing (S84).

  On the other hand, when it is determined that the operation in the depth direction is not being performed (S80: No), the add-on barcode is read out by moving the reading port 62 in the horizontal direction described above with reference to FIG. Is determined (determination process during operation at position (2): S200).

  The process in the determination process (2) being operated at the position of S200 will be described with reference to FIG. 11 showing a subroutine of the process. First, from the bar width value of 1 mm of the reading line calculated in S78, the depth [H? ] As the reading position, the distance from the end of the reading operation line to the barcode [W? ] Is calculated (S202). Then, it is determined whether the operation has just started (first decoding of the first code) (S204). Distance [W? ] Is obtained only once (S204: Yes), it is impossible to determine whether the operation in the horizontal direction is in progress, so the operation start is registered (S214), and the distance [ W? ] Is backed up as a distance [W_B] in the memory (S216), and the current time and the number of times of decoding are initialized (S218). And determining that there is no add-on barcode in S76 of FIG. 9 (S220).

  Here, in the case of the second and subsequent decoding (S204: No), it is determined whether a certain time (or a certain number of times of decoding) has passed since the previous comparison (S206). That is, since the decoding is repeated with a short cycle, the moving distance [W? ] Cannot be determined accurately, and until a predetermined time has elapsed (S206: No), the process proceeds to S220, and the determination of no add-on barcode is invalidated. On the other hand, if a certain time has elapsed (or a certain number of decoding repetitions) since the previous comparison (S206: Yes), the current distance [W? ] Is subtracted from the previous distance [W_B] to obtain the moving distance (S208). Then, it is determined whether the moving distance (absolute value) is smaller than a predetermined threshold YY (S210). Here, the absolute value is used as the moving distance in order to determine that the optical information reader 10 is being operated along the bar code when the optical information reader 10 is approached from either side in the left-right direction. Here, when the movement distance (absolute value) is larger than the predetermined threshold YY (S210: No), the optical information reader 10 is being operated in the horizontal direction, so that the process proceeds to S216, and the processes of S216 and S218 are performed. After that, the determination of no add-on barcode is invalidated (S220). On the other hand, when the movement distance (absolute value) is smaller than the predetermined threshold YY (S210: Yes), it is determined that the operation in the left-right direction with respect to the optical information reader 10 is completed (or not operated) (S212).

Here, the process in the determination process (2) during the operation at the position will be specifically described with reference to FIGS.
A position P4 shown in FIG. 16A represents a position where the optical information reader 10 is moved horizontally from the left direction to the bar code and the first code is successfully decoded. A position P5 shown in FIG. 16B represents a position where the first code has been successfully decoded after the lapse of a predetermined time in S206. Here, when the difference between the position P4 and the position P5 is larger than the predetermined threshold YY, the determination that there is no add-on barcode becomes invalid. For example, at the position P6 shown in FIG. Until the decoding of the code and the second code is successful, the output of the decoding result to the computer is waited.

  After the process of the determination process (2) during the operation at the position, it is further determined whether or not the operation in the horizontal direction is being performed in S82 shown in FIG. If it is determined that the operation in the horizontal direction is being performed (S82: Yes), the operator is notified by the sound of the buzzer 44 and the lighting of the LED 43, and waits until the add-on barcode can be read. Let them know that they are doing (S84). On the other hand, when the operation in the horizontal direction is not being performed (S82: No), the determination that the barcode is not an add-on barcode in S76 is utilized, and the decoding result of the first code is output to the computer (S86).

  In S64 of FIG. 9 described above, when the added value Y of the widths of the seven bars is within the allowable range (S64: Yes), it is assumed (judged) that there is an add-on barcode, and the assumption is incorrect. Whether or not there is an add-on barcode (correction of the above assumption) is determined in consideration of the inclination of the reading port 62 with respect to the arrangement direction of the first code (S300). The add-on barcode presence / absence determination process in S300 will be described with reference to FIGS. 12 and 17 to 19 showing a subroutine of the process. FIG. 17A is an explanatory diagram for explaining the angle threshold θt, and FIG. 17B is an explanatory diagram for explaining the perpendicular length threshold Dt. FIG. 18A is an explanatory diagram for explaining a state where the inclination angle θ is equal to or smaller than the angle threshold θt, and FIG. 18B illustrates a state where the perpendicular length D is equal to or smaller than a predetermined perpendicular length threshold Dt. It is explanatory drawing for demonstrating. FIG. 19 is an explanatory diagram for explaining a state where the inclination angle θ is not equal to or smaller than the angle threshold θt and the perpendicular length D is not equal to or smaller than the predetermined perpendicular length threshold Dt.

First, the widths of the bars constituting the first code are summed to calculate the width value of the first code as the actually measured width value A1 (S302). Next, the inclination angle θ between the reading line L1 and the barcode arrangement direction L2 is calculated (S304). Specifically, first, the distance from the line sensor 32 to the first code is measured using a separately provided distance sensor, and the prescribed width value of the first code is assumed from the measured distance . Therefore, the assumed width value of the first code is obtained as the assumed width value A2. Since the assumed width value A2 corresponds to the actually measured width value A1 when the inclination angle θ is 0 °, the inclination angle θ can be calculated by the following equation (5).
θ = cos ⁻¹ (A2 / A1) (5)
The inclination angle θ may correspond to an example of “an angle between the arrangement direction of the first code and the reading line” recited in the claims. Note that the control circuit 40 that executes S304 may correspond to an example of a “calculation unit” recited in the claims.

  Subsequently, it is determined whether or not the tilt angle θ calculated as described above is equal to or less than a predetermined angle threshold θt (S306). Here, as shown in FIG. 17A, the angle threshold θt is equal to the arrangement line L2 ′ when the arrangement line L2 ′ along the arrangement direction L2 of the main barcode Bm is passed through the center of the main barcode Bm. When the reading line L1 intersecting at the center left end of the main barcode Bm (indicated by the symbol Pa in FIG. 17A) passes through the right corner of the add-on barcode Ba, the reading line L1 and the array line L2 ′ It is set to be equal to the tilt angle.

  For this reason, as illustrated in FIG. 18A, if the inclination angle θ is equal to or smaller than the predetermined angle threshold θt (S306: Yes), the reading port 62 is not inclined greatly with respect to the arrangement direction L2. Assuming that the bar code has been read and the add-on bar code Ba exists, the add-on bar code presence / absence determination process in S300 is terminated. The control circuit 40 that executes S306 and S310, which will be described later, may correspond to an example of “determination means” recited in the claims.

On the other hand, when the inclination angle θ is not equal to or smaller than the predetermined angle threshold θt (S306: No), the process proceeds to S308, and the arrangement direction starts from the point where the left end when the add-on barcode Ba exists and the reading line L1 intersect. The perpendicular length D, which is the length of the perpendicular drawn along the array line L2 ″ along L2, is calculated from the gap width G and the inclination angle θ . The perpendicular length D corresponds to a distance in a direction orthogonal to the arrangement direction of the second cord and the first cord.

  Then, it is determined whether or not the perpendicular length D calculated as described above is equal to or less than a predetermined perpendicular length threshold Dt (S310). Here, as shown in FIG. 17B, the perpendicular length threshold value Dt is set such that when the array line L2 ″ is passed through the lower end of the main barcode Bm, the array line L2 ″ and the lower left end of the main barcode Bm ( The arrangement line from the point where the left end of the add-on barcode Ba and the reading line L1 intersect when the reading line L1 intersecting in FIG. 17B passes through the right corner of the add-on barcode Ba. It is set to be equal to the length of the perpendicular line dropped to L2 ″.

  For this reason, as illustrated in FIG. 18B, when the perpendicular length D is equal to or less than the predetermined perpendicular length threshold Dt (S310: Yes), the reading port 62 is not inclined greatly with respect to the arrangement direction L2. In step S300, the add-on bar code presence / absence determination process is terminated, assuming that the bar code has been read and the add-on bar code Ba exists.

  As described above, when it is determined Yes in S306 or Yes in S310 and the add-on bar code presence / absence determination process in S300 ends, the control circuit 40 determines that the second code is the add-on bar code Ba. Then, the second code is decoded and stored in the RAM of the memory 35 (S68). Next, the decoded data of the first code and the second code are transferred to the host device (computer) as the decoded data of the main bar code Bm and the add-on bar code Ba (S70), which is the end.

  On the other hand, as illustrated in FIG. 19, when the inclination angle θ is not equal to or smaller than the predetermined angle threshold θt (S306: No) and the perpendicular length D is not equal to or smaller than the predetermined perpendicular length threshold Dt (S310: No), an add-on is performed. Assuming that a bar code or pattern different from the bar code is displayed on the reading line L1, the add-on bar code presence / absence determination process in S300 is terminated, and the process proceeds to S86 to transfer the decoded data of the first code to the host device. And end.

FIG. 20A is a diagram showing a state where a part of the add-on barcode Ba is removed from the reading port 62, and FIG. 20B is a diagram showing a state where the bar at the left end of the second code is abnormally thick. FIG. 20C is a diagram showing a state where the first code and the second code are too far apart.
In this embodiment, as shown in FIG. 20A, the add-on barcode Ba is added to the main barcode Bm, but the add-on barcode Ba is not completely in the reading port 62. If the bar on the right side cannot be optically read, any of S38, S42, S46, S52, S56, and S60 may be determined as No. Therefore, if the buzzer 44 is sounded as described above, the user understands the buzzer sound as a warning that the bar code is out of the reading port 62, and the main bar code and add-on are read in the reading port 62. The optical information reader 10 is moved so that the bar code is inserted, and the reading operation is restarted by the trigger switch 18. As a result, the first code and the second code can be transferred to the main device (computer) as the main barcode Ba and the add-on barcode Ba as described above.

  As shown in FIG. 20B, the second code, which is an add-on barcode, has an extremely wide left end bar, and such a code is not an add-on barcode. However, in the conventional method of comparing the width of the last character of the first code and the width of the first character of the second code, the width of the wide bar at the left end is not taken into consideration, so in the case of FIG. The striped pattern is misjudged as an add-on barcode.

  On the other hand, in the present embodiment, since the added value Y of the bar widths from the left end of the second code to the seventh bar is compared with the reference value X, the right side of the first code is a striped pattern or the like, and an add-on barcode Therefore, it is possible to prevent a lot of time from being spent for wasteful decoding processing.

  As shown in FIG. 20C, a large gap exists between the barcode on the main side and the barcode on the right side of the barcode, and the barcode having such a large gap exists. Is not an add-on barcode. In this embodiment, if the gap width G between the main-side barcode and the add-on barcode is too wide compared to X, it is determined that the barcode is not an add-on barcode. It can prevent spending a lot of time.

  As described above, in the optical information reading apparatus 10 according to the present embodiment, when the received light signal includes two one-dimensional codes of the first code and the second code, the reading is performed with the arrangement direction L2 of the first code. The perpendicular angle D, which is the inclination angle θ with the line L1 or the distance in the direction orthogonal to the arrangement direction L2 between the second code and the first code, is calculated. The gap width G, which is the distance between the first code and the second code in the direction along the reading line L1, is 120% or more of the reference value X, which is a threshold value with which the second code can be regarded as an add-on barcode, and in S64 When it is determined Yes and the inclination angle θ is equal to or smaller than the angle threshold θt or the perpendicular length D is equal to or smaller than the perpendicular length threshold Dt, it is determined that the second code is the add-on barcode Ba. When it is determined that the second code is the add-on barcode Ba, the first code is the main barcode Bm, and the second code is the add-on barcode Ba, and the decoding process is performed.

As described above, since it is determined whether or not the second code is an add-on barcode according to either the inclination angle θ or the perpendicular length D, the reading port 62 of the apparatus has the first code arrangement direction. Even when the first code or the like is read while being tilted with respect to L2, the probability of erroneous determination that there is an add-on barcode can be reduced.
Therefore, even when reading is performed in a state where the reading port 62 is inclined with respect to the arrangement direction L2 of the first code, it is possible to improve the accuracy of the determination regarding the presence or absence of the add-on barcode.

  Furthermore, since it is determined whether or not the second code is an add-on barcode using both the inclination angle θ and the perpendicular length D, the accuracy of the determination regarding the presence or absence of the add-on barcode can be further improved.

  In particular, the angle threshold θt is set based on the array line L2 ′ passing through the center of the main barcode Bm (first code), and the perpendicular length threshold Dt is set to the array line L2 ″ passing through the lower end of the main barcode Bm. Is set based on. For this reason, in the positional relationship between the first code and the second code where the inclination angle θ is equal to or less than the angle threshold θt, the perpendicular length D is always equal to or less than the perpendicular length threshold Dt, and therefore the second code is used using the inclination angle θ. Is determined to be an add-on barcode Ba, the second code is always determined to be an add-on barcode Ba using the perpendicular length D. Accordingly, even in the configuration in which the presence / absence of the add-on barcode is determined using the inclination angle θ and the perpendicular length D, which are the two viewpoints, if the inclination angle θ is equal to or smaller than the angle threshold θt, the perpendicular length D is not required to be calculated. The processing load and processing time can be reduced compared with the case where the inclination angle θ and the perpendicular length D are always calculated.

  In the present embodiment, the inclination angle θ is the depth [H? ] And the actually measured width value A1 that is the width value of the first code obtained from the received light signal (S304), the angle can be easily calculated without preparing new measuring means separately. . Note that the depth [H? ] Can be regarded as a separation distance from the line sensor 32 to the first code.

In addition, this invention is not limited to the said embodiment, You may actualize as follows.
(1) Although an example in which the configuration of the present invention is applied to an optical information reading apparatus dedicated to barcode reading has been given, the present invention is applied to an optical information reading apparatus capable of reading a two-dimensional code together with a one-dimensional code such as a barcode. A configuration may be applied.

In (2) S304, not only from the distance sensor to determine the assumed width value A2, separately by the depth of [H? The estimated width value A2 or the inclination angle θ may be obtained by other measurement methods such as actually measuring a distance corresponding to

(3) In the add-on barcode presence / absence determination process of S300, S308 and S310 may be abolished, and it may be determined whether or not the second code has an add-on barcode based only on the inclination angle θ. S306 may be abolished and it may be determined whether or not the second code has an add-on barcode based only on the perpendicular length D.

(4) In the add-on barcode presence / absence determination process in S300, the processes in S304 and S306 may be performed after the processes in S308 and S310. In this case, the perpendicular length threshold Dt is set based on, for example, an array line L2 ′ that passes through the center of the main barcode Bm (first code), and the angle threshold θt is, for example, an array that passes through the lower end of the main barcode Bm. Set based on line L2 ″. For this reason, in the positional relationship between the first code and the second code where the perpendicular length D is equal to or less than the perpendicular length threshold value Dt, the inclination angle θ is always equal to or less than the angle threshold value θt. Is always determined to be an add-on barcode Ba, the second code is always determined to be an add-on barcode Ba using the inclination angle θ. Even in such a configuration, even when the presence or absence of the add-on barcode is determined using the inclination angle θ and the perpendicular length D, which are two viewpoints, the inclination angle θ is calculated if the perpendicular length D is equal to or less than the perpendicular length threshold Dt. Therefore, the processing load and the processing time can be reduced as compared with the case where the inclination angle θ and the perpendicular length D are always calculated.

DESCRIPTION OF SYMBOLS 10 ... Optical information reader 32 ... Line sensor (light-receiving means)
35 ... Memory 40 ... Control circuit (decoding means, calculation means, determination means)
62 ... Reading port D ... Vertical length Dt ... Vertical length threshold G ... Gap width L1 ... Reading line L2 ... Arrangement direction θ ... Tilt angle θt ... Angle threshold

Claims (1)

An optical information reader that optically reads a main bar code including a plurality of dark color patterns and light color patterns and an add-on bar code added in the vicinity of the main bar code as one one-dimensional code. And
A light receiving means for receiving reflected light from the one-dimensional code along a predetermined reading line;
Decoding means for performing decoding processing of a one-dimensional code based on a light receiving signal output from the light receiving means;
When the received light signal includes two one- dimensional codes, the first code located in the first reading direction is the first code, and the second code is the second one-dimensional code located in the reading direction . An angle between the arrangement direction of one code and the reading line is determined by using a distance sensor to measure a separation distance from the light receiving means to the first code and a width value of the first code obtained from the light reception signal. Calculating means for calculating from:
An interval between the first code and the second code in the direction along the reading line is equal to or greater than a threshold value at which the second code can be regarded as the add-on barcode, and a value calculated by the calculation means determines the second code. A determination unit that determines that the second code is the add-on barcode when the add-on barcode is equal to or lower than a threshold that can be regarded as the add-on barcode;
With
When the determination unit determines that the second code is the add-on barcode, the decoding unit decodes the first code as the main barcode and the second code as the add-on barcode. An optical information reader characterized by performing processing.

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