JP5765136B2 - Optical information reader - Google Patents

Description

  The present invention relates to an optical information reader that optically reads an information code.

  Conventionally, in an optical information reading apparatus that optically reads an information code, in order to prevent erroneous reading, the decoding results are compared for a plurality of times after the decoding processing is performed on the same information code, and the decoding results are matched. Only if read is successful.

  In particular, in the optical information reader disclosed in Patent Document 1 below, before the decoding process is executed, the degree of change in the total number of bars captured this time with respect to the total number of bars of bar code data captured last time is confirmed. Only when the degree of change is within the allowable range, the decoding process is executed. Therefore, the decoding process itself performed for appropriate image reading may be performed once, and high-speed reading is possible as compared with the conventional method of decoding a plurality of times and comparing the decoded data.

JP-A-11-250169

  By the way, when reading information by irradiating the information code with illumination light, specular reflection or the like occurs depending on the illumination state of the illumination light, and the area that should be identified as black (dark color) is misclassified as white (light color). If there are many such misidentified areas, decoding will fail. However, since the specular reflection or the like is weak, if there are only a few misidentified areas as described above, decoding may be successful and a decoding result may be obtained. In this case, there is a problem that even if the second decoding process is performed on the same information code, the irradiation state does not change, so that the decoding result matches and is erroneously read.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to suppress misreading in the case of judging the success or failure of decoding by comparing the decoding results for the same information code. An optical information reader is provided.

In order to achieve the above object, the optical information reader according to claim 1, illumination means (21, 21a, 21b) for irradiating illumination light (L1, L2) to the information code (C); Light receiving means (28) for receiving reflected light from the information code, decoding means (40) for decoding the information code based on a light reception signal output from the light receiving means, and a decoding result by the decoding means can be output. Output means (40), an optical information reader (10), wherein the illumination means comprises a plurality of light sources (22a-22e, 23a-23e), and each light source of the illumination means An irradiation state changing means (40) capable of changing an irradiation state of the illumination light with respect to the information code by changing at least one irradiation direction, and receiving reflected light from the information code When the first decoding result is decoded by the decoding unit based on the light reception signal output from the light receiving unit, the information is displayed in a state where the irradiation direction is changed by the irradiation state changing unit with respect to the information code. A comparison means (40) for comparing the second decoding result decoded by the decoding means with the first decoding result based on a light receiving signal output from the light receiving means that has received the reflected light from the code; The output means outputs the decode result when the two decode results compared by the comparison means match.

The invention according to claim 2 is an illumination means (21, 21a, 21b) for irradiating the information code (C) with illumination light (L1, L2), and a light receiving means for receiving the reflected light from the information code. (28), an optical device comprising: decoding means (40) for decoding the information code based on a light receiving signal output from the light receiving means; and output means (40) capable of outputting a decoding result by the decoding means. An information reading device (10) for receiving the reflected light from the information code, and an irradiation state changing means (40) capable of changing an irradiation state of the illumination light emitted from the illumination means to the information code; When the first decoding result is decoded by the decoding unit based on the received light signal output from the light receiving unit, the irradiation state changing unit is applied to the information code. The second decoding result and the first decoding result decoded by the decoding unit based on the light receiving signal output from the light receiving unit that has received the reflected light from the information code in a state in which the irradiation state is further changed Comparing means (40), and the output means outputs the decoding result when both the decoding results compared by the comparing means match, and the illuminating means includes a plurality of light sources ( 22a to 22e, 23a to 23e), and the illumination state changing unit alternately changes the illumination state to one of a lighting state and a light-off state for every other light source. The irradiation position in is changed.

The invention according to claim 3, in an optical information reading apparatus according to claim 2, irradiation state changes and outputs the decoding result by said output means when both decoded result of comparison by the comparison means match The mode, the decoding result decoded by the decoding means for the information code in a state where illumination light is irradiated from all the light sources, and the same information code without changing the irradiation position by the irradiation state changing means after this decoding A mode switching means (40) capable of switching to any one of a normal mode in which the decoding result is output by the output means when the decoding result decoded by the decoding means matches is provided.

According to a fourth aspect of the present invention, in the optical information reading apparatus according to any one of the first to third aspects, the light receiving means is a one-dimensional sensor in which the light receiving elements are arranged in one direction. .
In addition, the code | symbol in each said bracket | parenthesis shows the corresponding relationship with the specific means as described in each embodiment mentioned later.

In the first aspect of the invention, when the first decoding result is decoded, the light receiving means for receiving the reflected light from the information code in a state where the irradiation direction is changed by the irradiation state changing means for the information code The second decoding result decoded by the decoding unit based on the light reception signal output from the first decoding result is compared with the first decoding result. Then, when both decoding results compared by the comparison means match, the decoding result is output by the output means.

Thus, for the same information code, the irradiation direction when obtaining the first decoding result, since the irradiation direction when obtaining the second decoding results are different, due to the irradiation direction of such specular reflection Even if one of the two decoding results is an incorrect result, this one decoding result does not match the other decoding result.
Therefore, it is possible to suppress misreading when comparing the decoding results for the same information code to determine the success or failure of the decoding.

In the invention of claim 2, since the irradiation state changing means is alternately changed to either the lighting state or the extinguishing state for every other light source , the irradiation position in the illumination means is changed. It is possible to easily change the irradiation position .

In the third aspect of the invention, the mode switching unit emits illumination light from all light sources in the irradiation state change mode in which the decoding result output by the output unit is output when both decoding results compared by the comparison unit match. When the decoding result decoded by the decoding means for the information code in the state is coincident with the decoding result decoded by the decoding means for the same information code without changing the irradiation position after the decoding by the irradiation state changing means The mode can be switched to any one of the normal mode in which the decoding result is output by the output means.

  In the normal mode described above, it is possible to irradiate the information code with illumination light using all the light sources, so the reading success rate is improved compared to the case where the illumination code is irradiated with illumination light using some light sources. Thus, the reading workability may be improved. Therefore, when emphasizing prevention of misreading over reading workability, switch to the irradiation state change mode, and when emphasizing reading workability over prevention of misreading, switch to the normal mode so A mode can be selected according to the environment.

Even if the light receiving means is composed of a one-dimensional sensor in which the light receiving elements are arranged in one direction as in the invention of claim 4 , the misreading in the case of judging the success or failure of the decoding by comparing the decoding results for the same information code Can be suppressed.

1 is a block diagram illustrating an electrical configuration of an optical information reading device according to a first embodiment. It is explanatory drawing which shows the irradiation state by the illumination light source of FIG. 1, FIG. 2 (A) shows a 1st irradiation state, FIG.2 (B) shows a 2nd irradiation state. It is a wave form diagram which shows the example in which decoding failed because the light reception waveform was influenced by strong specular reflection. It is a wave form diagram for demonstrating the change of the received light waveform which changed the irradiation state about the same information code, and received light. 4 is a flowchart illustrating a flow of a reading process in the first embodiment. It is explanatory drawing which shows the irradiation state by the illumination light source in 2nd Embodiment, FIG. 6 (A) shows a 1st irradiation state and FIG. 6 (B) shows a 2nd irradiation state. It is explanatory drawing which shows the irradiation state by the illumination light source in 3rd Embodiment, FIG. 7 (A) shows a 1st irradiation state, FIG.7 (B) shows a 2nd irradiation state. 14 is a flowchart illustrating a flow of a reading process in the fourth embodiment.

[First Embodiment]
Hereinafter, an optical information reading apparatus according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an electrical configuration of an optical information reading apparatus 10 according to the first embodiment. FIG. 2 is an explanatory diagram showing an irradiation state by the illumination light source 21 of FIG. 1, FIG. 2 (A) shows a first irradiation state, and FIG. 2 (B) shows a second irradiation state.

  As shown in FIG. 1, the optical information reader 10 is configured as an apparatus that optically reads an information code such as a one-dimensional code or a two-dimensional code attached to an article. The optical information reading apparatus 10 includes a circuit unit 20 housed in a case (not shown). The circuit unit 20 mainly includes an illumination light source 21, a light receiving sensor 28, an imaging lens 27, and the like. And a microcomputer (hereinafter referred to as “microcomputer”) system such as a memory 35, a control circuit 40, and a trigger switch 42.

  The optical system is divided into a light projecting optical system and a light receiving optical system. The illumination light source 21 constituting the light projecting optical system includes a plurality of light sources in order to realize two types of irradiation states. Each of these light sources is, for example, a red LED and a lens provided on the emission side of the LED. And is composed respectively. Specifically, the illumination light source 21 includes three light sources 22a, 22b, and 22c constituting the first light source group 22 and three light sources constituting the second light source group 23, as shown in FIGS. 23a, 23b, and 23c are arranged in a straight line and alternately arranged.

  Thereby, as shown in FIG. 1 and FIG. 2 (A), the illumination light source 21 has a first irradiation state in which the illumination light L1 is irradiated from each of the light sources 22a, 22b, and 22c constituting the first light source group 22, and As shown in FIG. 2B, it is possible to irradiate two different types of irradiation states, the second irradiation state in which the illumination light L2 is irradiated from each of the light sources 23a, 23b, and 23c constituting the second light source group 23. Composed. The illumination light source 21 may correspond to an example of an “illuminating unit” described in the claims.

  The light receiving optical system includes a light receiving sensor 28, an imaging lens 27, a reflecting mirror (not shown), and the like. The light receiving sensor 28 is configured to receive the reflected light Lr irradiated and reflected by the information code C or the like. For example, a light receiving element which is a solid-state imaging element such as a C-MOS or CCD is arranged in one direction. This one-dimensional sensor (for example, a line sensor) corresponds to this. The light receiving sensor 28 is mounted on a printed wiring board (not shown) so as to be able to receive incident light incident through the imaging lens 27.

  The imaging lens 27 functions as an imaging optical system capable of condensing incident light incident from the outside via a reading port (not shown) and forming an image on the light receiving surface 28a of the light receiving sensor 28. . In the present embodiment, after the illumination light L1 or illumination light L2 emitted from the illumination light source 21 is reflected by the information code C, the reflected light Lr is condensed by the imaging lens 27, and the light receiving surface 28a of the light receiving sensor 28 is collected. A code image is formed on

  The microcomputer system includes an amplification circuit 31, an A / D conversion circuit 33, a memory 35, an address generation circuit 36, a synchronization signal generation circuit 38, a control circuit 40, a trigger switch 42, a light emitting unit 43, a buzzer 44, a vibrator 45, and a liquid crystal display. 46 and the like.

  The image signal (analog signal) output from the light receiving sensor 28 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. When the digitized image signal, that is, image data (image information) is generated and input to the memory 35, it is stored in a predetermined code image information storage area. The synchronization signal generation circuit 38 is configured to generate a synchronization signal for the light receiving sensor 28 and the address generation circuit 36, and the address generation circuit 36 is based on the synchronization signal supplied from the synchronization signal generation circuit 38. Thus, the storage address of the image data stored in the memory 35 can be generated.

  The memory 35 is a semiconductor memory device, and corresponds to, for example, a RAM (DRAM, SRAM, etc.) or a ROM (EPROM, EEPROM, etc.). In addition to the above-described code image information storage area, the RAM of the memory 35 is configured to be able to secure a work area and a reading condition table used by the control circuit 40 in each processing such as arithmetic operation and logical operation. Yes. The ROM stores in advance a predetermined program that can execute setting change processing, analysis processing, and the like, which will be described later, and a system program that can control each hardware such as the illumination light source 21 and the light receiving sensor 28. The memory 35 may correspond to an example of a “storage unit” described in the claims.

  The control circuit 40 is configured by a microcomputer capable of controlling the entire optical information reading apparatus 10, has a CPU, a system bus, an input / output interface, and the like, and has an information processing function. Is configured. In the present embodiment, a trigger switch 42, a light emitting unit 43, a buzzer 44, a vibrator 45, a liquid crystal display 46 and the like are connected to the control circuit 40.

  As a result, the control circuit 40 can, for example, turn on / off the light-emitting unit 43 that functions as an indicator for notifying information related to monitoring and management of the trigger switch 42 and reading of the information code C, and a buzzer that can generate a beep sound and an alarm sound. It is possible to turn on / off the ring 44, drive control of the vibrator 45 capable of generating vibration that can be transmitted to the user of the optical information reader 10, display control of the liquid crystal display 46, and the like.

Next, with respect to the optical information reading apparatus 10 configured as described above, a reading process for comparing the decoding result obtained by changing the irradiation state with respect to the same information code to determine the success or failure of the decoding will be described below. explain.
When reading the information code with illumination light, depending on the illumination light irradiation state, specular reflection may occur, and the area that should be identified as black (dark color) may be misidentified as white (light color). is there. For example, since strong specular reflection has occurred, as shown in FIG. 3, when a received light waveform having many misidentified areas (see the dashed-dotted ellipse shown in FIG. 3) is obtained, decoding is performed. Will fail. When such strong specular reflection occurs, the decoding does not succeed and fails, so the information code is not misread.

  However, since the specular reflection or the like is weak, as shown in FIG. 4A, the light reception waveform in which the above-described erroneous determination region (see the dashed-dotted ellipse shown in FIG. 4A) slightly occurs. If obtained, decoding may be successful and a decoding result may be obtained. In this case, even if the second decoding process is performed on the same information code, since the irradiation state does not change, almost the same received light waveform is obtained, and the decoding result matches and misreads.

  Therefore, in the reading process according to the present embodiment, the decoding result is determined by comparing the decoding results obtained by changing the irradiation state with respect to the same information code. Even if a light reception waveform (see FIG. 4A) that is misread due to specular reflection or the like is obtained in the first imaging, the irradiation state is changed from the first imaging in the second imaging, Since the received light waveform in which the region where the influence of the specular reflection is eliminated or misidentified at a different position (see the alternate long and short dash line ellipse shown in FIG. 4B) is obtained, two decoding results obtained by changing the irradiation state are obtained. This is because, if they do not match, it is determined that the decoding has failed, so that misreading caused by an irradiation state such as specular reflection is prevented.

  Hereinafter, the reading process executed by the control circuit 40 will be described in detail with reference to FIG. FIG. 5 is a flowchart illustrating the flow of the reading process in the first embodiment. In this reading process, the barcode is targeted for reading. However, the present invention is not limited to this, and the same effect can be obtained when a two-dimensional code such as a QR code (registered trademark), a data matrix code, or a maxi code is read.

  In this embodiment, when the user turns on the trigger switch 42 or the like, the reading process shown in FIG. 5 is started by the control circuit 40, and the first irradiation process shown in step S101 is performed. In this process, the illumination light L1 is emitted as the first irradiation state from each of the light sources 22a, 22b, and 22c constituting the first light source group 22 of the illumination light source 21 (see FIG. 2A).

  Next, when the imaging process shown in step S103 is performed and the illumination light L1 irradiated as the first irradiation state is reflected by the barcode and the reflected light Lr enters the imaging lens 27 through the reading port, the light is received. A bar code image, that is, a code image is formed on the light receiving surface 28 a of the sensor 28 by the imaging lens 27. Thereby, each light receiving element constituting the light receiving sensor 28 is exposed, and a light receiving signal corresponding to the barcode image is output from each light receiving element.

  Subsequently, the decoding process shown in step S105 is performed, and a known decoding process is performed on the code image obtained by the imaging process. When character data or the like is decoded by this process, it is determined Yes in the determination process shown in step S107, and the decoding result storage process shown in step S109 is performed. In this process, the decoding result obtained in the decoding process shown in step S105 is stored in the memory 35 as the first decoding result. If the decoding process fails, it is determined No in step S107, and the process from the imaging process shown in step S103 is performed.

  As described above, when the first decoding result is stored in the memory 35, the second irradiation process shown in step S111 is performed. In this process, the light sources 22a, 22b, and 22c of the first light source group 22 of the illumination light source 21 are turned off, and the illumination light L2 is set to the second irradiation state from the light sources 23a, 23b, and 23c constituting the second light source group 23. It changes to the irradiation state irradiated (refer FIG. 2 (B)). The control circuit 40 that executes the first irradiation process and the second irradiation process may correspond to an example of “irradiation state changing means” described in the claims.

  Next, the imaging process shown in step S113 is performed, and the illumination light L2 irradiated as the second irradiation state is irradiated to the same barcode decoded as described above, reflected by this barcode, and reflected light thereof. When Lr is received by the light receiving sensor 28, a light receiving signal corresponding to the barcode image is output.

  Subsequently, the decoding process shown in step S115 is performed, and a known decoding process is performed on the code image obtained by the imaging process. If character data or the like is decoded by this process, it is determined Yes in step S117, and if the decoding fails, it is determined No in step S117 and the process from the imaging process shown in step S113 is performed. Processing is done. The control circuit 40 that executes the decoding processing shown in steps S105 and S115 can correspond to an example of “decoding means” recited in the claims.

  If it is determined Yes in step S117, the decoding result obtained in the decoding process shown in step S115 (hereinafter referred to as the second decoding result) and the memory 35 are stored in the determination process shown in step S119. It is determined whether or not the first decoding result matches. Here, when the second decoding result and the first decoding result coincide with each other for the same barcode (Yes in S119), there is an erroneous determination area due to an irradiation state such as specular reflection in the received light waveform. If it is not included and the decoding is successful, the output process shown in step S121 is performed. In this process, the matching decoding result is output to the host system via the communication interface or the like as character data encoded as a barcode to be read.

  On the other hand, if the second decoding result and the first decoding result are different for the same barcode, the decoding result of at least one of both decoding results is incorrect due to the irradiation state such as specular reflection. It can be determined that Therefore, since the decoding results are different, if it is determined No in step S119, the processing from step S101 is performed without performing the output processing shown in step S121. The control circuit 40 that executes the determination process shown in step S119 may correspond to an example of “comparison means” described in the claims.

  As described above, in the optical information reading apparatus 10 according to the present embodiment, when the first decoding result is decoded, the irradiation state is changed from the barcode to the barcode. The second decoding result decoded based on the light reception signal output from the light receiving sensor 28 that has received the reflected light is compared with the first decoding result by the determination processing shown in step S119. When the compared decoding results match, this decoding result is output.

Thereby, for the same information code, the first irradiation state when the first decoding result is obtained is different from the second irradiation state when the second decoding result is obtained. Even if one of the two decoding results is an erroneous result due to the above, the one decoding result does not coincide with the other decoding result.
Therefore, it is possible to suppress misreading when comparing the decoding results for the same information code to determine the success or failure of the decoding.

  Also, the illumination light source 21 can be obtained by setting the light sources 22a, 22b, and 22c constituting the first light source group 22 to the irradiation state or setting the light sources 23a, 23b, and 23c constituting the second light source group 23 to the irradiation state. Since the irradiation state is changed to either the first irradiation state or the second irradiation state, the irradiation state can be easily changed in a short time.

  The first light source group 22 is not limited to being configured by the three light sources 22a, 22b, and 22c, and may be configured by two or four or more light sources. The second light source group 23 is not limited to the three light sources 23a, 23b, and 23c, and may be composed of two or four or more light sources. Further, the light sources 22a, 22b, 22c and the light sources 23a, 23b, 23c may be arranged according to a desired irradiation state without being arranged on a straight line. Moreover, the irradiation state of the illumination light source 21 is changed by changing at least one of the light sources of the illumination light source 21 configured in this way to one of a lighting state, a blinking state, and a light-off state. In addition, the irradiation state can be easily changed.

[Second Embodiment]
Next, an optical information reading apparatus 10 according to a second embodiment of the present invention will be described with reference to FIG. FIG. 6 is an explanatory diagram showing an irradiation state by the illumination light source 21a in the second embodiment, FIG. 6 (A) shows a first irradiation state, and FIG. 6 (B) shows a second irradiation state.
The optical information reader 10 according to the second embodiment is mainly different from the optical information reader according to the first embodiment in that an illumination light source 21a is employed instead of the illumination light source 21 described above. Therefore, substantially the same components as those of the optical information reading apparatus of the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIGS. 6A and 6B, the illumination light source 21a includes three light sources 22a, 22b, and 22c that constitute the first light source group 22, and three light sources 23a that constitute the second light source group 23. 23b and 23c are arranged and configured such that their irradiation directions are different from each other.

  Thereby, as shown in FIG. 6A, the illumination light source 21a is in the first irradiation state in which the illumination light L1 is irradiated from each of the light sources 22a, 22b, and 22c constituting the first light source group 22, and FIG. As shown in B), it is configured to be able to irradiate two different irradiation states, that is, the second irradiation state in which the illumination light L2 is irradiated from the respective light sources 23a, 23b, and 23c constituting the second light source group 23. .

  As described above, in the optical information reading apparatus 10 according to the present embodiment, the light sources 22a, 22b, and 22c that constitute the first light source group 22, and the light sources 23a, 23b that constitute the second light source group 23, and the like. 23c is arranged in such a manner that the irradiation directions are different from each other, and therefore the light application method is different. Therefore, irradiation between the first irradiation state by the first light source group 22 and the second irradiation state by the second light source group 23 is performed. Since the directions are different, the irradiation state can be changed reliably and easily.

[Third Embodiment]
Next, an optical information reading apparatus 10 according to a third embodiment of the present invention will be described with reference to FIG. FIG. 7 is an explanatory diagram showing an irradiation state by the illumination light source 21b in the third embodiment, FIG. 7 (A) shows a first irradiation state, and FIG. 7 (B) shows a second irradiation state.
The optical information reader 10 according to the second embodiment is mainly different from the optical information reader according to the first embodiment in that an illumination light source 21b is used instead of the illumination light source 21 described above. Therefore, substantially the same components as those of the optical information reading apparatus of the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIGS. 7A and 7B, the illumination light source 21b includes two light sources 22d and 22e constituting the first light source group 22, and two light sources 23d and 23e constituting the second light source group 23. The light sources 22d and 22e are arranged on the center side and the light sources 23d and 23e are arranged on the end side. In particular, each of the light sources 22d, 22e, 23d, and 23e is arranged so as to be inclined such that the light source located at the end side is directed toward the center.

  Thereby, as shown in FIG. 7A, the illumination light source 21b has a first irradiation state in which the illumination light L1 is emitted from each of the light sources 22d and 22e constituting the first light source group 22, and FIG. 7B. As shown in FIG. 2, the light source 23d and the light source 23e constituting the second light source group 23 are configured to be able to irradiate two different irradiation states, which are different from the second irradiation state in which the illumination light L2 is irradiated.

  As described above, in the optical information reading apparatus 10 according to the present embodiment, each of the light sources 22d, 22e, 23d, and 23e constituting the illumination light source 21b is on a straight line and is closer to the end side. Since the irradiation direction is arranged so as to be inclined toward the center, even if each light source is arranged on a straight line, a wider area can be irradiated with a small number of light sources. Thereby, the length of the arrangement direction in which the light sources 22d, 22e, 23d, and 23e are arranged in a straight line can be shortened, and the space-saving of the illumination light source 21b having the light sources 22d, 22e, 23d, and 23e can be reduced. Can be achieved.

[Fourth Embodiment]
Next, an optical information reading apparatus 10 according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a flowchart illustrating the flow of reading processing according to the fourth embodiment.
In the optical information reading apparatus 10 according to the fourth embodiment, the above-described reading processing is calculated based on the flowchart shown in FIG. 8 instead of the flowchart shown in FIG. Mainly different from such an optical information reader. Therefore, substantially the same components as those of the optical information reading apparatus of the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  In the optical information reading apparatus 10 according to the present embodiment, a mode change switch is provided. By operating this mode change switch before starting the reading process, in the reading process, the irradiation state change mode and the normal mode are changed. It is configured to be switched to any mode. Here, the irradiation state change mode is a mode in which the decoding result is output when the two decoding results compared by the determination processing shown in step S119 described above match. The normal mode is a mode in which the decoded result is output when the decoded results match without changing the irradiation state for the same information code.

Hereinafter, the reading process according to the fourth embodiment will be described with reference to the flowchart of FIG.
In the present embodiment, when the reading operation shown in FIG. 8 is started by the control circuit 40 by the user turning on the trigger switch 42, the determination process shown in step S201 is performed, and the irradiation state change mode is set. It is determined whether or not it is selected. Here, when the mode changeover switch is operated so as to select the irradiation state change mode (Yes in S201), the processing after Step S101 is performed as in the first embodiment described above.

  On the other hand, when the mode changeover switch is operated so as to select the normal mode (No in S201), all the irradiation processes shown in Step S203 are performed, and the light sources 22a, 22b, Illumination light is irradiated from all the light sources 22c and the respective light sources 23a, 23b, and 23c constituting the second light source group 23. Note that the mode changeover switch and the control circuit 40 that executes the determination process shown in step S201 may correspond to an example of a “mode changeover unit” recited in the claims.

  In this manner, with the illumination light irradiated from all the light sources, the imaging process shown in step S205 and the decoding process shown in step S207 are performed in the same manner as the imaging process shown in step S103 and the decoding process shown in step S105. If successful (Yes in S209), the decoding result storing process shown in step S211 is performed, and the decoding result is stored in the memory 35 as the first decoding result.

  When the first decoding result is stored in the memory 35 in this way, the imaging process shown in step S213 and the decoding process shown in step S215 are performed in the imaging process shown in step S113 without changing the irradiation state by the illumination light source 21. And the same processing as the decoding process shown in step S115 is performed. When the decoding is successful (Yes in S217), the decoding result obtained in the decoding process shown in Step S115 (hereinafter referred to as the second decoding result) is stored in the memory 35 in the determination process shown in Step S119. It is determined whether or not the first decoded result matches.

  Here, for the same barcode, when the second decoding result and the first decoding result match (Yes in S219), the output processing shown in step S121 is performed, and the matching decoding result is output. The On the other hand, since the decoding results are different, if it is determined No in step S219, the processing from step S201 is performed without performing the output processing shown in step S121.

  As described above, in the optical information reading apparatus 10 according to the present embodiment, the mode is switched to either the irradiation state change mode or the normal mode according to the operation of the mode switch.

  In the normal mode described above, the illumination light can be applied to the barcode using all of the light sources 22a, 22b, 22c, 23a, 23b, and 23c. Therefore, the illumination light is applied to the barcode using a part of the light sources. As compared with the case, the reading success rate may be improved and the reading workability may be improved. Therefore, when emphasizing prevention of misreading over reading workability, switch to the irradiation state change mode, and when emphasizing reading workability over prevention of misreading, switch to the normal mode so A mode can be selected according to the environment.

  In the present embodiment, the mode changeover switch is used as the mode changeover means for switching between the irradiation state change mode and the normal mode. However, the present invention is not limited to this, and an operation for inputting information is operated. It may be configured to switch to either the irradiation state change mode or the normal mode by making a determination in the determination process in step S201 according to information input from the unit or the external device.

In addition, this invention is not limited to said each embodiment and modification, You may actualize as follows.
(1) The light receiving sensor 28 is not limited to the one-dimensional sensor in which the light receiving elements are arranged in one direction, and even if the light receiving sensor 28 is composed of an area sensor in which the light receiving elements are two-dimensionally arranged, It is possible to suppress misreading when comparing the decoding results to determine the success or failure of the decoding.

(2) The illumination light sources 21, 21 a, and 21 b perform the first irradiation by switching between the irradiation state in which the illumination light is irradiated from the first light source group 22 and the irradiation state in which the illumination light is irradiated from the second light source group 23. The first irradiation state and the second irradiation state are changed by changing at least one irradiation direction of each light source with an actuator or the like, not limited to being configured to change the state and the second irradiation state. It may be configured to.

DESCRIPTION OF SYMBOLS 10 ... Optical information reader 21,21a, 21b ... Illumination light source (illumination means)
22 ... 1st light source group 22a, 22b, 22c, 22d, 22e ... Light source 23 ... 2nd light source group 23a, 23b, 23c, 23d, 23e ... Light source 28 ... Light receiving sensor (light receiving means)
40 ... Control circuit (decoding means, output means, irradiation state changing means, comparison means, mode switching means)
L1, L2 ... Illumination light

Claims (4)

An illumination means for illuminating the information code with illumination light;
A light receiving means for receiving reflected light from the information code;
Decoding means for decoding the information code based on a light receiving signal output from the light receiving means;
Output means capable of outputting a decoding result by the decoding means;
An optical information reader comprising:
The illumination unit includes a plurality of light sources,
An irradiation state changing unit capable of changing an irradiation state of the illumination light with respect to the information code by changing an irradiation direction of at least one of the light sources of the illumination unit;
When the first decoding result is decoded by the decoding unit based on the light reception signal output from the light receiving unit that has received the reflected light from the information code, the irradiation state changing unit irradiates the information code. The second decoding result and the first decoding result decoded by the decoding unit based on the light receiving signal output from the light receiving unit that has received the reflected light from the information code in a state where the direction is changed. A comparison means for comparing;
With
The optical information reading apparatus according to claim 1, wherein the output means outputs the decoding result when both decoding results compared by the comparing means match. An illumination means for illuminating the information code with illumination light;
A light receiving means for receiving reflected light from the information code;
Decoding means for decoding the information code based on a light receiving signal output from the light receiving means;
Output means capable of outputting a decoding result by the decoding means;
An optical information reader comprising:
An irradiation state changing means capable of changing an irradiation state of the illumination light irradiated from the illumination means with respect to the information code;
When the first decoding result is decoded by the decoding unit based on the light reception signal output from the light receiving unit that has received the reflected light from the information code, the irradiation state changing unit irradiates the information code. The second decoding result and the first decoding result decoded by the decoding unit based on the light receiving signal output from the light receiving unit that has received the reflected light from the information code in a state changed. A comparison means for comparing;
With
The output means outputs the decoding result when both decoding results compared by the comparing means match,
The illumination unit includes a plurality of light sources,
The irradiating state changing means, said plurality of light sources with respect to, by changing to one of the alternating lighting state and off state every other, you and changing the irradiation position of the illumination means light Scientific information reader. An irradiation state change mode for outputting the decoding result by the output means when both decoding results compared by the comparison means match, and the decoding means for the information code in a state in which illumination light is irradiated from all the light sources When the decoding result decoded by the decoding means matches the decoding result decoded by the decoding means for the same information code without changing the irradiation position by the irradiation state changing means after the decoding, the decoding result is output by the output means. The optical information reading apparatus according to claim 2, further comprising a mode switching unit capable of switching to any one of a normal mode and a normal mode . The optical information reading apparatus according to claim 1 , wherein the light receiving unit includes a one-dimensional sensor in which light receiving elements are arranged in one direction .

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