Optical reading device

Abstract

To provide a technology for notifying a user of a positional relation of a display medium with respect to an optical reading device.SOLUTION: An optical reading device includes: a housing; a photographing unit exposed on a surface of the housing; an antenna fixed to the surface of the housing; a first output unit which outputs a first notification sound indicating that the display medium is approaching the photographing unit, in a situation where a display medium for displaying information codes is approaching the surface, and decrease of a magnetic flux generated on the surface by the antenna is detected; and a process execution unit which, when the photographing unit photographs the display codes displayed on the display medium, executes a process for reading information from the information codes photographed by the photographing unit.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to an optical reader that optically reads information from an information code. [Background technology]

[0002] Patent Document 1 discloses a mobile terminal having display units on both the front and back sides. An information code is displayed on the display unit on the back side. An image captured by a camera located on the back side is displayed on the display unit on the front side. The image includes an image of a code reader that reads information from the information code, and a user of the mobile terminal can see the positional relationship between the mobile terminal and the code reader by looking at the image on the display unit on the front side. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-016061 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology of Cited Document 1 is premised on a special mobile terminal having display units on both the front and back sides. This specification provides a technology for informing a user of the positional relationship of a display medium with respect to an optical reading device, without premised on a special mobile terminal. [Means for solving the problem]

[0005] The optical reading device disclosed in this specification comprises a housing, an imaging unit exposed on the surface of the housing, an antenna fixed to the surface of the housing, a first output unit that outputs a first notification sound indicating that the display medium is approaching the imaging unit when a decrease in the magnetic flux generated on the surface by the antenna is detected when the display medium displays an information code and the magnetic flux is detected to be decreasing, and a processing execution unit that executes processing to read information from the information code imaged by the imaging unit when the imaging unit images the information code displayed on the display medium.

[0006] The inventors focused on a configuration in which an imaging unit and an antenna are arranged on the surface of a housing. In this configuration, the more the display medium covers the surface, the less magnetic flux the antenna generates on the surface. Covering the surface by the display medium indicates that the display medium is approaching the imaging unit. According to the above configuration, a first notification sound is output based on the decrease in magnetic flux by the antenna. The user can hear the first notification sound and know that the display medium is approaching the imaging unit. The proximity of the display medium to the imaging unit prompts the user to capture an image of an information code displayed on the display medium. The above antenna is a component for reading information from a storage medium, such as an IC chip. In recent years, multifunctional devices capable of reading information not only from information codes but also from storage media have emerged. Such multifunctional devices have both an imaging unit and an antenna. The technology disclosed herein can be realized by improving such multifunctional devices.

[0007] When it is detected that the magnetic flux is further decreasing, the first output unit may output a second notification sound that indicates that the display medium is getting closer to the imaging unit, the second notification sound being different from the first notification sound.

[0008] According to the above configuration, the user can hear the second notification sound different from the first notification sound and know that the display medium is getting closer to the imaging unit.

[0009] When the first output unit detects that the magnetic flux is increasing after decreasing, the first output unit may output a third notification sound indicating that the display medium is moving away from the imaging unit, the third notification sound being different from the first notification sound.

[0010] According to the above configuration, the user can hear the third notification sound and know that the display medium that was once close has moved away from the imaging unit.

[0011] The optical reading device may further include a second output unit that outputs a first guidance sound indicating a movement direction in which the display medium should be moved to include the entire information code within the field of view of the imaging unit when a portion of the information code is included within the field of view of the imaging unit after the first notification sound is output.

[0012] According to the above configuration, the first notification sound can guide the user so that the information code of the display medium approaching the imaging unit is within the angle of view of the imaging unit.

[0013] The optical reading device may further include a proximity sensor exposed on the surface of the housing and positioned adjacent to the imaging unit, and a third output unit that outputs a second guidance voice urging the user to bring the display medium closer to the imaging unit when, after the first notification sound is output, the imaging unit does not include an image showing the characteristics of the information code within its field of view and the proximity sensor detects the presence of the display medium.

[0014] According to the above configuration, the proximity sensor adjacent to the imaging unit can be used to detect a situation where the information code of the display medium is not within the angle of view of the imaging unit even though the display medium is approaching the imaging unit, and in this situation, the user can be guided to bring the information code of the display medium within the angle of view of the imaging unit.

[0015] The optical reading device may further include a proximity sensor exposed on the surface of the housing, and a fourth output unit that outputs a third guidance voice prompting the user to adjust the height of the display medium relative to the surface when the output value of the proximity sensor is outside a predetermined value range.

[0016] The predetermined range is set to, for example, a height at which the imaging unit is focused on the information code. According to the above configuration, it is possible to prompt the user to adjust the height of the display medium so that the imaging unit is focused on the information code.

[0017] The antenna may include two or more partial antennas arranged side by side on the surface, and when it is detected that the magnetic flux generated on the surface by a specific partial antenna among the two or more partial antennas is decreasing, the first output unit may output the first notification sound including a sound that guides the display medium in a direction toward which the remaining partial antenna among the two or more partial antennas is located.

[0018] By following the sound, if the display medium is moved in the direction of the remaining partial antenna, the surface will be covered further by the display medium, and the display medium will move closer to the imaging unit. By using two or more partial antennas, it is possible to not only be informed that the display medium is approaching the imaging unit, but also to be informed of the direction in which the display medium should be moved. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 2 is a schematic diagram of a mobile terminal and a payment terminal. [Figure 2] FIG. 2 is a block diagram of a payment terminal. [Figure 3] FIG. 10 is a flowchart of processing of the payment terminal. [Figure 4] FIG. 1 is a diagram illustrating a state in which a mobile terminal moves. [Figure 5] FIG. 10 is a diagram illustrating a specific case of guidance processing. [Figure 6] FIG. 10 is a schematic diagram of a payment terminal according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] (First Example) (Configuration of payment terminal 10; Figures 1 and 2) The payment terminal 10 is a terminal that accepts operations for paying for items to be purchased. The payment terminal 10 is installed, for example, in a store that sells the items to be purchased. The payment terminal 10 may be a stationary or portable terminal.

[0021] The payment terminal 10 includes an imaging unit 12, a chip reader 14, a speaker 16, a proximity sensor 18, a display unit 20, and a control unit 30. Note that the speaker 16 and the control unit 30 are not shown in FIG.

[0022] The imaging unit 12 includes an image sensor and captures, for example, an information code (e.g., a barcode or a two-dimensional code). The image of the information code captured by the imaging unit 12 is decoded by the control unit 30. As a result, the control unit 30 reads information recorded in the information code. The information read from the information code is, for example, information that identifies a user and is used for payment.

[0023] The chip reader 14 reads payment information stored in a contactless IC chip. Contactless IC chips are provided in credit cards, electronic money, mobile phones, etc. The payment information includes, for example, identification information such as a credit card number, user information, etc.

[0024] The chip reader 14 includes an antenna 14a for communicating with the contactless IC chip. The communication with the contactless IC chip is, for example, wireless communication according to the Near Field Communication (NFC) method.

[0025] The proximity sensor 18 is a sensor that detects the presence of an object approaching the payment terminal 10. The proximity sensor 18 can also measure the distance to the object. The proximity sensor 18 is, for example, a laser sensor.

[0026] The display unit 20 displays various information. The display unit 20 is, for example, a liquid crystal display, an organic EL display, etc. The display unit 20 may include a touch screen.

[0027] The control unit 30 controls each of the units 12 to 20. The control unit 30 includes a CPU 32 and a memory 34. The CPU 32 executes the processing of FIG.

[0028] As shown in Fig. 1, an imaging unit 12, a proximity sensor 18, and a display unit 20 are exposed on a surface 10b of a housing 10a of a payment terminal 10. The imaging unit 12 and the proximity sensor 18 are located to the left of the display unit 20 on the paper. The imaging unit 12 and the proximity sensor 18 are aligned in the vertical direction on the paper. Note that Fig. 1 is merely an example showing the positional relationship between the imaging unit 12, the proximity sensor 18, and the display unit 20.

[0029] 1, antenna 14a is fixed to surface 10b of housing 10a so as to surround display unit 20. Antenna 14a is hidden from view from surface 10b. Note that FIG. 1 is merely an example showing the arrangement of antenna 14a.

[0030] The payment terminal 10 is a multi-functional device equipped with an imaging unit 12 and a chip reading unit 14, and is capable of reading information not only from information codes but also from storage media such as contactless IC chips. For example, when making a payment using the information in an information code, the user brings the mobile terminal 100 displaying the information code close to the surface 10b of the payment terminal 10. The user then adjusts the position of the mobile terminal 100 relative to the imaging unit 12 so that the information code falls within the angle of view of the imaging unit 12. The technology of this embodiment aims to assist the user in making the above-mentioned position adjustment.

[0031] (Processing of payment terminal 10; Figures 3 to 5) 3 to 5, the process executed by the CPU 32 of the payment terminal 10 in accordance with the program 40 will be described. The process of FIG. 3 is started, for example, when a code payment instruction is input to the payment terminal 10. The code payment instruction is an instruction to execute a payment using an information code.

[0032] In S2, the CPU 32 activates the imaging unit 12. This starts imaging by the imaging unit 12. In S4, the CPU 32 activates the chip reading unit 14. This starts emitting radio waves from the antenna 14a of the chip reading unit 14, and a magnetic flux is generated on the surface 10b of the housing 10a.

[0033] In S10, the CPU 32 starts measuring the increase or decrease of the magnetic flux on the surface 10b of the casing 10a. The magnetic flux is estimated, for example, from the amount of current flowing in the chip reader 14. The magnetic flux may also be measured by a sensor capable of measuring magnetic flux.

[0034] For example, when the surface 10b is not covered by the mobile terminal 100, magnetic flux is generated over the entire surface 10b. As shown in case C1 in Fig. 4, the closer the mobile terminal 100 is to the imaging unit 12, the larger the area of ​​the surface 10b that the mobile terminal 100 covers. The larger the area of ​​the surface 10b that the mobile terminal 100 covers, the smaller the magnetic flux generated on the surface 10b by the antenna 14a.

[0035] In S12, the CPU 32 outputs a notification sound from the speaker 16 based on the measurement result of the increase or decrease in magnetic flux in S10. The notification sound is, for example, a predetermined sound effect. The CPU 32 does not output the notification sound if the measurement result in S10 indicates that the amount of magnetic flux has remained unchanged from the maximum amount. The maximum amount of magnetic flux is, for example, the amount of magnetic flux when the surface 10b is not covered by the mobile terminal 100. The CPU 32 outputs the notification sound at a first frequency if the measurement result in S10 indicates that the amount of magnetic flux has decreased from the maximum amount. Then, the CPU 32 outputs the notification sound at a second frequency higher than the first frequency if the measurement result in S10 indicates that the amount of magnetic flux has further decreased from the maximum amount. For example, in case C1 of FIG. 4, the notification sound is output at a first frequency, and in case C2, the notification sound is output at a second frequency. That is, when transitioning from case C1 to case C2 occurs, the frequency of the notification sound increases. The user hears the notification sound that gradually increases in frequency, and is able to know that the mobile terminal 100 is gradually approaching the imaging unit 12. Note that the frequency of the notification sound is not limited to the above two stages, but may increase in three or more stages. In a modified example, instead of the frequency of the notification sound, the volume or pitch of the notification sound may be changed.

[0036] It is also possible to return from case C2 to case C1. In this case, the frequency of the notification sound returns from the second frequency to the first frequency. The user hears the notification sound with a reduced frequency and can know that the mobile terminal 100, which once approached, is now moving away from the imaging unit 12.

[0037] In the next step S14, the CPU 32 determines whether the mobile terminal 100 has reached the imaging unit 12. For example, if the measurement result in S10 indicates that the amount of magnetic flux is less than a predetermined amount and then increases again, the CPU 32 determines that the mobile terminal 100 has reached the imaging unit 12. As shown in case C3 in FIG. 4, when the mobile terminal 100 reaches the imaging unit 12, the area that the mobile terminal 100 covers on the surface 10b becomes smaller than in case C2. As a result, the amount of magnetic flux generated on the surface 10b increases. In a modified example, the CPU 32 may determine that the mobile terminal 100 has reached the imaging unit 12 when an image showing characteristics of an information code (for example, an image having a black and white pattern) is included within the angle of view of the imaging unit 12.

[0038] If the CPU 32 determines that the mobile terminal 100 has not reached the imaging unit 12 (NO in S14), the process returns to S12. On the other hand, if the CPU 32 determines that the mobile terminal 100 has reached the imaging unit 12 (YES in S14), the process proceeds to S16.

[0039] In S16, the CPU 32 determines whether or not an image showing the characteristics of the information code is included within the angle of view of the imaging unit 12. If the CPU 32 determines that an image showing the characteristics of the information code is included within the angle of view of the imaging unit 12 (YES in S16), the CPU 32 proceeds to S20.

[0040] In S20, the CPU 32 determines whether the output value of the proximity sensor 18 is within a predetermined range. Here, the predetermined range is set to a height at which the focus of the imaging unit 12 is aligned with the information code. If the CPU 32 determines that the output value of the proximity sensor 18 is within the predetermined range (YES in S20), the process proceeds to S22.

[0041] In S22, the CPU 32 analyzes the image captured by the imaging unit 12 and executes a guidance process for guiding the movement of the mobile terminal 100. FIG. 5 shows an example of the guidance process. In the guidance process, the angle of view 200 of the imaging unit 12 is divided into six regions A1 to A6. In case D1, a part of the information code 110 displayed on the mobile terminal 100 is included in region A6. In this case, the CPU 32 outputs, from the speaker 16, a guidance voice including a direction (e.g., "up and left") to move the information code 110 (i.e., the mobile terminal 100) to region A1 diagonally opposite region A6. In case D2, a part of the information code 110 is included in region A5. In this case, the CPU 32 outputs a guidance voice including a direction (e.g., "up") to move the information code 110 (i.e., the mobile terminal 100) to region A2 above region A5. The user moves the mobile terminal 100 in accordance with the guidance voice. As a result, as shown in case D3, the entire information code 110 is included within the angle of view 200. By the guidance process of S22, the process transitions from case C3 to case C4 in FIG. 4, and the information code 110 displayed on the mobile terminal 100 is positioned above the imaging unit 12.

[0042] When the processing of S22 ends, the CPU 32 proceeds to S40. In S40, the CPU 32 determines whether or not the reading of information from the information code 110 was successful. If the CPU 32 determines that the reading of information from the information code 110 was successful (YES in S40), the CPU 32 proceeds to S42. On the other hand, if the CPU 32 determines that the reading of information from the information code 110 was unsuccessful (NO in S40), the CPU 32 returns to S16.

[0043] In S42, the CPU 32 executes the payment process using the information read in S40. When S42 ends, the process of FIG.

[0044] Furthermore, when the CPU 32 determines that an image showing the characteristics of the information code is not included within the angle of view of the imaging unit 12 (NO in S16), the process proceeds to S18. In S18, the CPU 32 determines whether the proximity sensor 18 is in the "ON" state, in which it is outputting an output value. The proximity sensor 18 being in the "ON" state means that an object is present above the proximity sensor 18. A situation in which NO is determined in S16 and YES is determined in S18 is, for example, a situation in which the mobile terminal 100 has transitioned from case C3 to case C5 in FIG. 4. That is, this is a situation in which the mobile terminal 100 is displaced from the imaging unit 12.

[0045] When the CPU 32 determines that the proximity sensor 18 is in the "ON" state (YES in S18), the CPU 32 proceeds to S30. In S30, the CPU 32 outputs, via the speaker 16, a misalignment notification sound indicating that the mobile terminal 100 is misaligned with the imaging unit 12. The misalignment notification sound includes, for example, a direction from the proximity sensor 18 toward the imaging unit 12 (e.g., "down"). This allows the user to know that the mobile terminal 100 is misaligned with the imaging unit 12, and to move the mobile terminal 100. That is, in the situation of case C5, the CPU 32 can guide the user so that the information code 110 fits within the angle of view of the imaging unit 12. When S30 ends, the CPU 32 returns to S16.

[0046] Furthermore, if the CPU 32 determines that the proximity sensor 18 is not in the "ON" state (NO in S18), the process proceeds to S32. In S32, the CPU 32 outputs an error sound from the speaker 16 indicating that the mobile terminal 100 is out of alignment with both the imaging unit 12 and the proximity sensor 18. When S16 ends, the CPU 32 ends the processing of FIG. 3.

[0047] Furthermore, when the CPU 32 determines that the output value of the proximity sensor 18 is outside the predetermined value range (NO in S20), the CPU 32 proceeds to S24. In S24, the CPU 32 outputs, via the speaker 16, a height guidance audio message urging the user to adjust the height of the mobile terminal 100 relative to the surface 10b. For example, if the output value of the proximity sensor 18 is greater than the upper limit of the predetermined value range, this means that the mobile terminal 100 is too high relative to the surface 10b. In this case, the height guidance audio message includes a message urging the user to lower the height of the mobile terminal 100 relative to the surface 10b. For example, if the output value of the proximity sensor 18 is less than the lower limit of the predetermined value range, this means that the mobile terminal 100 is too low relative to the surface 10b. In this case, the height guidance audio message includes a message urging the user to raise the height of the mobile terminal 100 relative to the surface 10b. With this configuration, it is possible to urge the user to adjust the height of the mobile terminal 100 so that the focus of the imaging unit 12 is on the information code 110. When the processing of S24 ends, the CPU 32 returns to S16.

[0048] (Effects of this embodiment) According to the configuration of this embodiment, a notification sound is output based on a decrease in magnetic flux by the antenna 14a (S12 in FIG. 3). The user can hear the notification sound and know that the mobile terminal 100 is approaching the imaging unit 12. When the mobile terminal 100 approaches the imaging unit 12, the user is prompted to capture an image of the information code 110 displayed on the mobile terminal 100. The technology of this embodiment can be used to assist visually impaired people. Furthermore, the configuration of this embodiment can be realized by improving a multi-functional payment terminal equipped with the imaging unit 12 and the chip reading unit 14.

[0049] Furthermore, in this embodiment, in addition to outputting the notification sound in S12 utilizing the decrease in magnetic flux, the payment terminal 10 executes a guidance process in S22 utilizing an image captured by the imaging unit 12. Although the guidance using the notification sound utilizing the decrease in magnetic flux moves the information code 110 closer to the angle of view 200, the entire information code 110 does not necessarily fit within the angle of view 200. This is because, as shown in FIG. 4 , when the information code 110 is directed toward the imaging unit 12, the information code 110 is generally hidden by the back surface of the mobile terminal 100 and cannot be seen, making it impossible for the user to accurately grasp the position of the information code 110. By executing the guidance process in S22, it is possible to guide the user so that the information code 110 fits within the angle of view 200, even if the user cannot accurately grasp the position of the information code 110.

[0050] (Correspondence) The payment terminal 10, the housing 10a, and the surface 10b are examples of an "optical reader," a "housing," and a "surface," respectively. The imaging unit 12 and the antenna 14a are examples of an "imaging unit" and an "antenna," respectively. The mobile terminal 100 and the information code 110 are examples of a "display medium" and an "information code," respectively. The notification sound in cases C1 and C2 is an example of a "first notification sound." When the notification sound in case C1 is the "first notification sound," the notification sound in case C2 is an example of a "second notification sound." When the notification sound in case C2 is the "first notification sound," the notification sound in case C1 is an example of a "third notification sound." The guidance voice output in the guidance process of S22 in FIG. 3 is an example of a "first guidance voice." The offset guidance voice in S30 is an example of a "second guidance voice." The height guidance voice in S24 is an example of a "third guidance voice." The control unit 30 that executes the process of S12 is an example of a "first output unit." The control unit 30 that executes the process of S40 is an example of a "processing execution unit."

[0051] (Second Example) (Configuration of payment terminal 10; Figure 6) The payment terminal 10 of this embodiment is equipped with six partial antennas 301-306 instead of one antenna 14a. The six partial antennas 301-306 are arranged side by side on the surface 10b. The number of partial antennas is not limited to six, and may be two, three, four, five, seven or more.

[0052] (Processing of payment terminal 10; Figure 3) In this embodiment, in the process of S10, an increase or decrease in magnetic flux of each of the six partial antennas 301 to 306 is measured. In this embodiment, after the process of S10 is completed, the CPU 32 executes the process of S50 instead of S12. In S50, when the CPU 32 detects a decrease in magnetic flux generated on the surface 10b by a specific partial antenna among the six partial antennas 301 to 306, the CPU 32 outputs a direction guidance notification from the speaker 16. The direction guidance notification is a sound that guides the user in the direction of the remaining partial antenna among the six partial antennas 301 to 306. For example, in the case of FIG. 6, the specific partial antenna is the partial antenna 306 at the bottom right of the page. In this case, the direction guidance notification includes a direction (e.g., "upper left") to move to the partial antenna 301 diagonally opposite the partial antenna 306. When the mobile terminal 100 is moved in accordance with the direction guidance notification, the mobile terminal 100 further covers the surface 10b, and the mobile terminal 100 moves closer to the imaging unit 12. Also, in other cases where the specific partial antennas are two partial antennas 306 and 305, the direction guidance notification includes the direction to move to partial antenna 301. By using two or more partial antennas 301 to 306, it is possible to not only be notified that the mobile terminal 100 is approaching the imaging unit 12, but also to be guided as to the direction in which the mobile terminal 100 should be moved.

[0053] The six partial antennas 301 to 306 are an example of “two or more partial antennas.” The direction guidance notification is an example of a “first notification sound.”

[0054] Although specific examples of the technology disclosed in this specification have been described above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. For example, the following modifications may be adopted.

[0055] (Modification 1) The "optical reader" is not limited to the payment terminal 10, but may be, for example, a code reader that does not have a payment function.

[0056] (Modification 2) The "display medium" is not limited to the mobile terminal 100, but may be, for example, another medium on which the information code 110 is written (for example, a ticket, a member card, or a coupon).

[0057] (Modification 3) The notification sound may remain unchanged in S12 of Fig. 3. In this modification, the "second notification sound" can be omitted.

[0058] (Variation 4) In S12 of Fig. 3, even if the magnetic flux decreases and then increases again, the notification sound may continue to be output at the second frequency. In this variation, the "third notification sound" can be omitted.

[0059] (Modification 5) The process of S22 in Fig. 3 does not have to be executed. In this modification, the "first guidance voice" can be omitted.

[0060] (Variation 6) The process of S30 in Fig. 3 does not have to be executed. In this variation, the "second voice guidance" can be omitted.

[0061] (Variation 7) The process of S24 in Fig. 3 does not have to be executed. In this variation, the "third voice guidance" can be omitted.

[0062] (Variation 8) The decoding of the information code may be performed not only by the control unit 30 but also by an external device (e.g., a server) that can communicate with the payment terminal 10. In this case, the control unit 30 transmits the captured image captured by the imaging unit 12 to the external device. In this variation, the control unit 30 that transmits the captured image to the external device is an example of a "processing execution unit."

[0063] (Variation 9) The "optical reading device" may be a portable device. In this case, the display medium may be fixed, and the portable optical reading device may approach the display medium. When the portable optical reading device approaches the display medium, a notification sound may be output.

[0064] The technical elements described in this specification or drawings exhibit technical utility either alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technologies illustrated in this specification or drawings simultaneously achieve multiple objectives, and achieving one of those objectives is itself technically useful. [Explanation of symbols]

[0065] 10: Payment terminal 10a: Housing 10b: Surface 12: Imaging unit 14: Chip reader 14a: Antenna 16: Speaker 18: Proximity sensor 20: Display section 30: Control section 32 :CPU 34: Memory 40: Program 100: Mobile devices 110: Information code 200: Angle of view 301~306: Partial antennas A1~A6: Area

Claims

1. An optical reader, The housing and an imaging unit exposed on a surface of the housing; an antenna fixed to the surface of the housing; a first output unit that outputs a first notification sound indicating that the display medium is approaching the imaging unit when it is detected that the magnetic flux generated on the surface by the antenna is decreasing in a situation where the display medium that displays an information code is approaching the surface; and a processing execution unit that executes, when the imaging unit images the information code displayed on the display medium, a processing for reading information from the information code imaged by the imaging unit; An optical reading device comprising:

2. 2. The optical reading device of claim 1, wherein the first output unit outputs a second notification sound, different from the first notification sound, when it detects that the magnetic flux is further decreasing, indicating that the display medium is getting closer to the imaging unit.

3. 2. The optical reading device of claim 1, wherein the first output unit outputs a third notification sound, different from the first notification sound, indicating that the display medium is moving away from the imaging unit when it detects that the magnetic flux is increasing after decreasing.

4. The optical reader further comprises:

2. The optical reading device of claim 1, further comprising a second output unit that outputs a first guidance sound indicating a direction in which the display medium should be moved to include the entire information code within the field of view of the imaging unit when a portion of the information code is included within the field of view of the imaging unit after the first notification sound is output.

5. The optical reader further comprises: a proximity sensor exposed on the surface of the housing and disposed adjacent to the imaging unit; a third output unit that outputs a second guidance voice prompting the user to bring the display medium closer to the imaging unit when an image showing characteristics of the information code is not included within the angle of view of the imaging unit and the proximity sensor detects the presence of the display medium after the first notification sound is output; 5. An optical reading device according to claim 1, comprising:

6. The optical reader further comprises: a proximity sensor exposed on the surface of the housing; a fourth output unit that outputs a third guidance voice prompting the user to adjust the height of the display medium relative to the surface when the output value of the proximity sensor is outside a predetermined value range; 5. An optical reading device according to claim 1, comprising:

7. The antenna includes two or more partial antennas; the two or more partial antennas are arranged side by side on the surface; 5. The optical reading device of claim 1, wherein the first output unit outputs the first notification sound including a sound that guides the display medium in the direction where the remaining partial antenna of the two or more partial antennas is located when it detects that the magnetic flux generated on the surface by a specific partial antenna of the two or more partial antennas is decreasing.

Images