Information code reading device

Abstract

The present application provides an information code reading device which can read information codes covered by a coating layer which is not permeable to visible light and information codes displayed on a screen. In a state where visible light is irradiated by first illumination units (21a to 24a), an information code is read by a first reading unit (25a). In a state where infrared light is irradiated by second illumination units (21b to 24b), an information code is read by a second reading unit (25b). A visible light cut filter (29) which is not permeable to visible light but permeable to infrared light is arranged corresponding to the reading range of the second reading unit (25b).

Description

TECHNICAL FIELD

[0001] The present application relates to an information code reading apparatus, and particularly to an information code reading apparatus for reading an information code in which coded information is written, such as a one-dimensional code or a two-dimensional code. BACKGROUND

[0002] In recent years, there has been a demand for security of information codes, and as a technology related to a reading apparatus that optically reads such information codes with improved security, for example, an information code reading apparatus disclosed in Patent Literature 1 is known.

[0003] An information code that is a reading target of the information code reading apparatus has modules arranged in a code region, in which a dark-color module that exhibits a dark-colored reflection characteristic when visible light (light of a first wavelength band) or infrared light (light of a second wavelength band) is irradiated and a light-color module that exhibits a dark-colored reflection characteristic when visible light is irradiated and exhibits a light-colored reflection characteristic when infrared light is irradiated are printed. Therefore, the information code reading apparatus is provided with a first illumination light source that irradiates visible light, a second illumination light source that irradiates infrared light, and a photographing section that photographs the information code in a state in which either light is irradiated, and is configured to extract and interpret the information code from a photographed image of the information code photographed by the photographing section. That is, the information code as a reading target can be interpreted on the basis of a photographed image photographed in a state in which infrared light is irradiated. On the other hand, in a normal environment in which visible light is irradiated, the entire code region becomes dark-colored, and not only the information code cannot be photographed, but also the information code itself is not visible, and thus the security of the information code is improved.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2012-133743 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] However, by covering at least a part of the code region with a coating section that does not transmit visible light but transmits light of the second wavelength band such as infrared light, it is possible to improve the security of the information code, and in the case of photographing and interpreting such an information code, there is a case in which the photographed information code cannot be interpreted due to the influence of the surrounding environment and the like. That is, this is because in an environment in which the surrounding visible light is too bright with respect to the light of the second wavelength band irradiated from the reading apparatus, for example, in an outdoor environment in which sunlight is irradiated and the like, reflected light from the coating section is photographed even when the light of the second wavelength band is irradiated due to excessive irradiation of visible light, and the code region covered with the coating section cannot be photographed for interpretation.

[0009] To solve this problem, a configuration is considered in which a filter that does not transmit visible light but transmits light of a second wavelength band is provided to the imaging section. By filtering out the visible light reflected at the coating section with this filter, it is possible to image the light of the second wavelength band reflected at the corresponding code area.

[0010] However, in the imaging section that employs such a filter, other problems such as the inability to image a normal information code displayed on a liquid crystal screen or the like can occur. This is because a liquid crystal screen displays an information code using visible light, and in the imaging section that employs the above filter, even a liquid crystal screen on which an information code or the like is displayed will be imaged in a completely dark state.

[0011] The present application has been made to solve the above technical problem, and has an object to provide an information code reading apparatus that can not only image an information code covered with a coating section that does not transmit visible light but also image an information code displayed through a screen.

[0012] Solution to the technical problem

[0013] To achieve the above object, an information code reading apparatus (1) according to a first embodiment is characterized by comprising:

[0014] a first illumination section (21a to 24a) that can irradiate visible light (Lfa);

[0015] a second illumination section (21b to 24b) that can irradiate light (Lfb) of a prescribed second wavelength band that is different from the wavelength band of the visible light;

[0016] a first imaging section (25a) that images an information code in a state in which the visible light is irradiated by the first illumination section;

[0017] a second imaging section (25b) that images an information code in a state in which the light of the second wavelength band is irradiated by the second illumination section;

[0018] a filter (29) that is disposed corresponding to the imaging range of the second imaging section and that does not transmit visible light but transmits the light of the second wavelength band; and

[0019] a processing section (31) that performs processing to interpret an information code based on at least either one of a first captured image captured by the first imaging section and a second captured image captured by the second imaging section.

[0020] Furthermore, the marks in the above parentheses indicate a correspondence relationship with the specific solutions described in the embodiments that will be described later.

[0021] Effects of the Invention

[0022] In the information code reading apparatus according to the first embodiment, the first imaging section images the information code in a state where the first illuminating section irradiates the visible light, and the second imaging section images the information code in a state where the second illuminating section irradiates the light of the second wavelength band. In addition, a light filter that does not transmit the visible light but transmits the light of the second wavelength band is arranged in the imaging range of the second imaging section.

[0023] Thus, if the reading target is an information code whose code region is covered with a coating section that does not transmit the visible light but transmits the light of the second wavelength band such as infrared light, the reflected light from the code region due to the irradiation of the light of the second wavelength band is transmitted through the coating section, and thus the information code can be interpreted based on the second captured image captured by the second imaging section. In particular, in the imaging range of the second imaging section, since the light filter that does not transmit the visible light but transmits the light of the second wavelength band is arranged, the reflected light from the coating section is not captured even in an outdoor environment or the like where the ambient visible light is excessively bright. On the other hand, if the reading target is a normal information code displayed on a liquid crystal screen or the like, the information code can be interpreted based on the first captured image captured by the first imaging section. Thus, not only the information code covered with the coating section that does not transmit the visible light but also the information code displayed through the screen can be captured in a readable manner.

[0024] In the information code reading apparatus according to the second embodiment, the first illuminating section is controlled by the illumination control section so as to irradiate the visible light at the time of imaging by the first imaging section, and the second illuminating section is controlled so as to irradiate the light of the second wavelength band at the time of imaging by the second imaging section.

[0025] Thus, in the first imaging section and the second imaging section, the visible light and the light of the second wavelength band can be simultaneously irradiated at the same time point in the case of imaging at the same time point, and the irradiation time points of the visible light and the light of the second wavelength band can be staggered in accordance with the time points in the case of imaging at different time points.

[0026] In the information code reading apparatus according to the third embodiment, based on the result of the analysis processing of at least a part of the first captured image and the second captured image, the setting section sets either one of the first captured image and the second captured image as an interpretation target of the processing section. Then, the processing section performs the processing of interpreting the information code based on the captured image set as the interpretation target by the setting section.

[0027] Thus, the captured image that is easily interpreted among the first captured image and the second captured image can be set as the interpretation target of the processing section, and thus the processing load related to the interpretation processing can be reduced as compared with the case where the two captured images are separately interpreted.

[0028] In the information code reading apparatus according to the fourth embodiment, the processing for extracting the specific pattern within the code region from the first captured image and the second captured image, respectively, is executed, and the captured image in which the number of the specific pattern extracted is large is set as the reading target of the processing section.

[0029] There is a possibility that the captured image in which all the specific patterns are captured is readable, and the captured image in which all the specific patterns are not captured is not readable or is difficult to read. Therefore, by setting the reading target in accordance with the number of the specific patterns extracted, the reading target can be easily set, and the processing load related to the reading processing can be further reduced.

[0030] In the information code reading apparatus according to the fifth embodiment, the specific region in each of the first captured image and the second captured image is binarized, the processing for counting the number of changes in black and white along one or more than two scan lines within the specific region is executed, and the captured image in which the number of changes is large is set as the reading target of the processing section.

[0031] If the captured image in which the information code is captured in a readable manner is captured by taking a part of a range in which the information code is easily captured in the captured image as the above-described specific region, the number of changes in black and white along each scan line within the specific region becomes large because the light color code elements and the dark color code elements arranged in plurality are included in the specific region. On the other hand, in the case where the number of changes in black and white along each scan line within the above-described specific region is small, there is a possibility that the information code is not captured in a readable manner and the information code is captured in a non-readable or difficult-to-read manner. Therefore, by setting the reading target in accordance with the number of changes in black and white within the specific region, the reading target can be easily set, and thus the processing load related to the reading processing can be further reduced.

[0032] In the information code reading apparatus according to the sixth embodiment, the other filter which does not transmit the light of the second wavelength band but transmits the visible light is arranged corresponding to the capturing range of the first capturing section. Thus, when the information code is captured by the first capturing section in a state in which the visible light is irradiated, even if the light of the second wavelength band is irradiated by the second illuminating section, the first capturing section does not capture the reflected light generated by the irradiation of the light of the second wavelength band, and thus the information code can be captured more clearly without being affected by the irradiation of the light of the second wavelength band.

[0033] In the information code reading apparatus according to the seventh embodiment, the first capturing section and the second capturing section are arranged in the housing in which the reading surface is provided, so that the center of the field of view of the first capturing section and the center of the field of view of the second capturing section intersect at the center of the reading surface, in a manner that the information code scanned on the reading surface can be captured.

[0034] When the first and second photographing sections are simply arranged in the housing with their respective field-of-views centered orthogonally with respect to the reading surface, the first and second photographing sections have different photographing ranges on the reading surface, so the optimal reading surface position when scanning an information code covered by the aforementioned coating section is different from the optimal reading surface position when scanning an information code displayed on the screen. Therefore, by arranging the first and second photographing sections so that their respective field-of-views intersect at the center of the reading surface where information codes are easily scanned, the optimal reading surface position when scanning an information code covered by the aforementioned coating section and the optimal reading surface position when scanning an information code displayed on the screen can be made to coincide at the center of the reading surface.

[0035] In the information code reading apparatus according to the eighth embodiment, the housing houses at least the first and second illumination sections, the first and second photographing sections, and the filter, and is provided with a reading surface on which the information code is scanned. The reflection member is housed in the housing and reflects the visible light emitted from the first illumination section and the light of the second wavelength band emitted from the second illumination section toward the reading surface.

[0036] In the information code reading apparatus according to the ninth embodiment, the reflection member is provided to reflect the visible light emitted from the first illumination section and the light of the second wavelength band emitted from the second illumination section toward the reading surface. When the range in the photographing range of the first photographing section that is formed between the first imaging section provided to the first photographing section and the reading surface is defined as a first pre-reflection photographing range, the range formed between the reading surface and the reflection member in a manner that is continuous to the first pre-reflection photographing range in the case where the light is reflected toward the inside of the housing from the reading surface is defined as a first post-reflection photographing range, the range in the photographing range of the second photographing section that is formed between the second imaging section provided to the second photographing section and the reading surface is defined as a second pre-reflection photographing range, and the range formed between the reading surface and the reflection member in a manner that is continuous to the second pre-reflection photographing range in the case where the light is reflected toward the inside of the housing from the reading surface is defined as a second post-reflection photographing range, the reflection member is arranged at a position outside the first pre-reflection photographing range and outside the second pre-reflection photographing range, and the first and second illumination sections, the first and second photographing sections, and the filter are arranged at a position outside the first post-reflection photographing range and outside the second post-reflection photographing range. The visible light is emitted from the first illumination section toward the first reflection surface of the reflection member that is the first post-reflection photographing range, and the light of the second wavelength band is emitted from the second illumination section toward the second reflection surface of the reflection member that is the second post-reflection photographing range.

[0037] Thus, when the information code scanned on the reading surface is imaged, even if a portion inside the housing from the reading surface is projected into the imaging image due to reflection of the display surface or the like that displays the information code, the entirety of the first reflecting surface of the reflection member irradiated with the visible light and the entirety of the second reflecting surface of the reflection member irradiated with the light of the second wavelength band are easily imaged. Therefore, compared with the case where the first illumination portion and the second illumination portion are directly imaged, the required illuminance can be ensured in the imaging image, and the illumination light (the visible light and the light of the second wavelength band) does not stand out, and the light noise generated by the illumination light is suppressed. Thus, even in the case where the first illumination portion and the second illumination portion are accommodated in the housing, the influence of the light noise generated by the reflection of the illumination light on the imaging image can be suppressed.

[0038] Hereinafter, more exemplary structures are provided with respect to the above-described various modes. These structural features will become clear through the description of the various embodiments described later. Figure 1 These structural features will become clear through the description of the various embodiments described later. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 is a plan view of an information code reading apparatus according to the first embodiment.

[0040] Figure 2 is a cross-sectional schematic view schematically showing an X1-X1 cross section of Figure 1

[0041] Figure 3 is a cross-sectional schematic view schematically showing an X2-X2 cross section of Figure 1

[0042] Figure 4 is a block diagram illustrating an electrical structure of the information code reading apparatus of Figure 1

[0043] Figure 5 is a schematic view illustrating the irradiation states of the first illumination portion and the second illumination portion using the light guide member.

[0044] Figure 6 (A) of FIG. 10 is a schematic view illustrating a first imaging image in which the information code Ca is imaged, Figure 6 (B) of FIG. 10 is a schematic view illustrating a second imaging image in which the information code Ca is imaged.

[0045] Figure 7 (A) of FIG. 11 is a schematic view illustrating a first imaging image in which the information code Cb displayed through the screen is imaged, Figure 7 (B) of FIG. 11 is a schematic view illustrating a second imaging image in which the information code Cb displayed through the screen is imaged.

[0046] Figure 8 ​​​This is a flowchart illustrating the reading process performed by the control unit in the first embodiment.

[0047] Figure 9 This is a flowchart illustrating the reading process performed by the control unit in the second embodiment.

[0048] Figure 10 (A) is a schematic diagram illustrating a specific area of ​​the first captured image containing the information code Ca. Figure 10 (B) is a schematic diagram illustrating a specific area of ​​the second captured image containing the information code Ca.

[0049] Figure 11 (A) is a schematic diagram illustrating a specific area of ​​the first captured image of the information code Cb displayed on the screen. Figure 11 (B) is a schematic diagram illustrating a specific area of ​​the second captured image of the information code Cb displayed on the screen.

[0050] Figure 12 This is a schematic cross-sectional view showing the main parts of the information code reading device according to the third embodiment.

[0051] Figure 13 This is a schematic cross-sectional view showing the main parts of the information code reading device according to the fourth embodiment.

[0052] Figure 14 This is a schematic cross-sectional view showing the main parts of the information code reading device according to a variation of the fourth embodiment.

[0053] Figure 15 This is a perspective view showing the information code reading device according to the fifth embodiment.

[0054] Figure 16 yes Figure 15 A top view of the information code reading device.

[0055] Figure 17 It is shown in general terms. Figure 16 A schematic cross-sectional view of section X3-X3.

[0056] Figure 18 It is shown in general terms. Figure 16 A schematic cross-sectional view of section X4-X4.

[0057] Figure 19 It is shown in general terms. Figure 16 A schematic cross-sectional view of section X5-X5.

[0058] Figure 20 This is a schematic diagram illustrating the main components of the information code reading device according to the sixth embodiment.

[0059] Figure 21 (A) is a schematic view illustrating an irradiation direction in which light from the first side surface side is emitted as illumination light, Figure 21 (B) is a schematic view illustrating an irradiation direction in which light from the second side surface side is emitted as illumination light.

[0060] Figure 22 is a schematic view illustrating a main part of an information code reading apparatus according to a first modification of the sixth embodiment.

[0061] Figure 23 is a schematic view illustrating a main part of an information code reading apparatus according to a second modification of the sixth embodiment.

[0062] Figure 24 is a cross-sectional schematic view illustrating a main part of an information code reading apparatus according to the seventh embodiment.

[0063] Figure 25 is Figure 24 a plan view of the information code reading apparatus of

[0064] Figure 26 is an enlarged view illustrating a main part of an information code reading apparatus according to a modification of the seventh embodiment.

[0065] Figure 27 is a plan view of an information code reading apparatus according to the eighth embodiment.

[0066] Figure 28 is a plan view of an information code reading apparatus according to a first modification of the eighth embodiment.

[0067] Figure 29 is a plan view of an information code reading apparatus according to a second modification of the eighth embodiment. DETAILED DESCRIPTION

[0068] [First Embodiment]

[0069] Hereinafter, a first embodiment of an information code reading apparatus according to the present application will be described with reference to the drawings.

[0070] (Overall structure of information code reading apparatus)

[0071] Figures 1 to 3 The information code reading apparatus 1 shown in FIGS. 1 to 3 is configured to be placed on an upper surface of a table or a shelf or the like as a placement surface (see FIG. 3). The information code reading apparatus 1 is configured to read an information code on an information code medium 2 placed on the placement surface. Figure 2 , Figure 3The fixed reading device placed on the placement surface F) has a function as an information code reader that reads one-dimensional codes such as bar codes or two-dimensional codes such as QR codes (registered trademark).

[0072] The information code reading device 1 is provided with a housing 3 composed of a resin material such as ABS resin. As shown in Figure 2 and Figure 3 , the housing 3 is provided with an upper housing 4a and a lower housing 4b, and has a rectangular shape in plan view having a length direction, and is configured in a box shape as a whole. Further, in the inside of the housing 3, various parts such as an imaging section, a photographing section, a light guide member, and the like to be described later are accommodated. In addition, on the upper surface portion (reading side wall portion 3a) of the housing 3 provided on one side in the prescribed up-down direction UD with the plate material 7 to be described later having light transmissivity interposed therebetween, an optical reading port 5 as an entrance and exit of light is formed. Through the reading port 5, light from the outside of the housing 3 enters the inside of the housing 3, and light from the inside of the housing 3 exits to the outside of the housing 3. Further, an optical system composed of the imaging section and the photographing section functions to photograph an information code or the like arranged outside the housing 3 through the reading port 5.

[0073] On the housing 3 configured in a box shape, a bottom wall portion 3b provided on the side of the placement surface F when the information code reading device 1 is placed, and a reading side wall portion 3a on which the reading port 5 is formed are provided in opposition to each other. Further, the bottom wall portion 3b faces the side of the placement surface F, and is arranged in opposition to the placement surface F, and further, is configured to be supported by the placement surface F. Further, the reading side wall portion 3a in opposition to the bottom wall portion 3b is configured as an exposed wall portion on the side of scanning an information code or the like. In addition, in the present structure, the direction of opposition of the bottom wall portion 3b and the reading side wall portion 3a (that is, the thickness direction of the housing 3, the direction orthogonal to the placement surface F, as shown in Figure 2 , the up-down direction UD (refer to Figure 2 , Figure 3 ), and the side on which the reading port 5 is formed (the reading side wall portion 3a side) is taken as the upper side, and the opposite side thereof (the bottom wall portion 3b side) is taken as the lower side. In addition, the direction along the virtual two-dimensional plane orthogonal to the up-down direction UD is taken as the horizontal plane direction HR (refer to Figure 2 , Figure 3 ).

[0074] As shown in Figure 2 and Figure 3As shown in FIG. 1, a plate 7 is disposed on the upper surface side of the housing 3, and the plate 7 is configured to close the housing 3 in a structure in which an opening portion 4c formed at the upper end portion of the upper housing 4a is closed, and at least a portion thereof is disposed in the imaging range. The plate 7 is configured as a flat plate of a predetermined thickness, and is composed of a light-transmissive member (for example, a transparent acrylic resin or a transparent glass, or the like) that is transmissive to light from the outside of the housing 3. The plate 7 functions as a dust-proof plate, and by the plate 7 closing the opening portion 4c formed in the upper housing 4a, foreign matter (dust or dirt, or the like) from the outside of the housing 3 is difficult to enter the inside of the housing 3. In addition, a coating layer 8 is formed, and the coating layer 8 is composed of a light-shielding paint or the like in a structure in which the coating layer 8 partially covers the upper surface portion of the plate 7. The coating layer 8 is formed in a ring shape along the peripheral portion of the plate 7, and an opening portion composed of the inner edge portion of the coating layer 8 functions as a reading port 5.

[0075] Next, the electrical structure of the information code reading apparatus 1 will be described.

[0076] As shown in FIG. 1, a plate 7 is disposed on the upper surface side of the housing 3, and the plate 7 is configured to close the housing 3 in a structure in which an opening portion 4c formed at the upper end portion of the upper housing 4a is closed, and at least a portion thereof is disposed in the imaging range. The plate 7 is configured as a flat plate of a predetermined thickness, and is composed of a light-transmissive member (for example, a transparent acrylic resin or a transparent glass, or the like) that is transmissive to light from the outside of the housing 3. The plate 7 functions as a dust-proof plate, and by the plate 7 closing the opening portion 4c formed in the upper housing 4a, foreign matter (dust or dirt, or the like) from the outside of the housing 3 is difficult to enter the inside of the housing 3. In addition, a coating layer 8 is formed, and the coating layer 8 is composed of a light-shielding paint or the like in a structure in which the coating layer 8 partially covers the upper surface portion of the plate 7. The coating layer 8 is formed in a ring shape along the peripheral portion of the plate 7, and an opening portion composed of the inner edge portion of the coating layer 8 functions as a reading port 5. Figure 4 As shown in FIG. 1, a plate 7 is disposed on the upper surface side of the housing 3, and the plate 7 is configured to close the housing 3 in a structure in which an opening portion 4c formed at the upper end portion of the upper housing 4a is closed, and at least a portion thereof is disposed in the imaging range. The plate 7 is configured as a flat plate of a predetermined thickness, and is composed of a light-transmissive member (for example, a transparent acrylic resin or a transparent glass, or the like) that is transmissive to light from the outside of the housing 3. The plate 7 functions as a dust-proof plate, and by the plate 7 closing the opening portion 4c formed in the upper housing 4a, foreign matter (dust or dirt, or the like) from the outside of the housing 3 is difficult to enter the inside of the housing 3. In addition, a coating layer 8 is formed, and the coating layer 8 is composed of a light-shielding paint or the like in a structure in which the coating layer 8 partially covers the upper surface portion of the plate 7. The coating layer 8 is formed in a ring shape along the peripheral portion of the plate 7, and an opening portion composed of the inner edge portion of the coating layer 8 functions as a reading port 5.

[0077] The control section 31 is configured as an example with a microcomputer as the main body. Specifically, the control section 31 has a CPU (central processing unit) 31A responsible for computation, a main memory 31B as a work area, and a system bus, an input / output interface, and the like not shown, and constitutes an information processing apparatus together with a memory 32. The control section 31 is configured to interpret data stored in the information code by a predetermined interpretation method through reading processing using an imaging image of the information code imaged by the optical system to be described later. In the memory 32 (including a RAM (random-access memory) and a ROM (read-only memory)), a predetermined program and the like for executing reading processing and the like are stored in advance in a manner executable by the control section 31. Therefore, the memory 32 functions as a non-transitory computer-readable recording medium, and stores a program (to be described later) related to the steps of the reading processing as source code. The program is executed by the CPU 31A reading from the main memory 31B. The main memory 31B is configured to be readable and writable by a RAM or the like. The CPU 31A is an element that is the center of computation of the microcomputer system, and the name thereof can be different (for example, a processor) as long as it has the same function.

[0078] Furthermore, the read processing performed by the control unit 31 (i.e., CPU 31A) will be described later.

[0079] In addition, the information code reading device 1, in order to optically read information codes, includes an optical system comprising an illumination unit and an imaging unit, which are controlled by a control unit 31 (i.e., CPU 31A). The optical system is divided into a projection optical system and a receiving optical system. The illumination unit constituting the projection optical system includes: first illumination units 21a to 24a, which function as a light source that can illuminate visible light via LEDs or the like; and second illumination units 21b to 24b, which function as a light source that can illuminate light in a predetermined second wavelength band, specifically infrared light, which is different from the wavelength band of visible light. The first illumination units 21a to 24a and the second illumination units 21b to 24b are configured such that their illumination state can be controlled by the control unit 31, which functions as an illumination control unit.

[0080] like Figure 1 as well as Figure 2 As shown, pairs of first lighting units 21a and second lighting units 21b, and pairs of first lighting units 22a and second lighting units 22b are provided on one side of the housing 3 along its length (width direction WD). Additionally, pairs of first lighting units 23a and second lighting units 23b, and pairs of first lighting units 24a and second lighting units 24b are provided on the other side of the housing 3 along its length (width direction WD). Each of the first lighting units 21a-24a and each of the second lighting units 21b-24b is configured to illuminate the housing 3 towards its center in the horizontal plane direction HR.

[0081] like Figures 1 to 3 As shown, the projection optical system includes a light guide component 50, which guides illumination light from each of the first illumination units 21a-24a and each of the second illumination units 21b-24b. This light guide component 50 is disposed inside the housing 3 at the position where the illumination light from each of the first illumination units 21a-24a and each of the second illumination units 21b-24b is irradiated, and is configured to guide this illumination light through the opening area of ​​the reading port 5 to irradiate the outside of the housing 3.

[0082] The light guide component 50 has four reflective portions 51 to 54 as reflective surfaces for reflecting illumination light from each of the first illumination portions 21a to 24a and each of the second illumination portions 21b to 24b. Reflective portions 51 and 52 are positioned opposite each other in the front-back direction FB, which is orthogonal to the aforementioned length direction (width direction WD). Reflective portions 53 and 54 are positioned opposite each other in a direction orthogonal to the front-back direction FB (i.e., the width direction WD), and are each configured as an inclined surface that decreases as it approaches the other side. Furthermore, the light guide component 50 as a whole has a conical shape outside the imaging range of the imaging portion, wherein the size of the aperture (opening area) narrows as it moves downwards. In addition, reflective portions 51 to 54 are, for example, made of light-shielding components, and the reflective surfaces that reflect illumination light are of a predetermined color (e.g., a bright color such as white), and are all configured to diffuse and reflect incident light outwards.

[0083] Furthermore, the first illumination part 21a and the second illumination part 21b, along with the first illumination part 22a and the second illumination part 22b, are configured to irradiate illumination light from near the upper end position of the reflective part 53 of the light guide member 50 toward the reflective part 54 and the reflective parts 51 and 52. Additionally, the first illumination part 23a and the second illumination part 23b, along with the first illumination part 24a and the second illumination part 24b, are configured to irradiate illumination light from near the upper end position of the reflective part 54 of the light guide member 50 toward the reflective part 53 and the reflective parts 51 and 52.

[0084] Through this structure, such as Figure 5 As shown, the illumination light emanating from each of the first illumination sections 21a-24a and each of the second illumination sections 21b-24b illuminates the reflective surface of the light guide member 50, which is configured as a cone shape, thus brightening the reflective sections 51-54 as a whole. Furthermore, in Figure 4 For ease of explanation, the illustration of the light guide component 50 is omitted. The visible light irradiated by the first illumination unit 21a to 24a toward the information code C displayed on the object being read R is illustrated as illumination light Lfa, and the infrared light irradiated by the second illumination unit 21b to 24b is illustrated as illumination light Lfb.

[0085] like Figure 4 As shown, the light-receiving optical system consists of two imaging units (hereinafter also referred to as the first imaging unit 25a and the second imaging unit 25b) and two imaging units (hereinafter also referred to as the first imaging unit 27a and the second imaging unit 27b).

[0086] The first imaging unit 25a and the second imaging unit 25b are, for example, composed of a light-receiving sensor (area sensor) with solid-state imaging elements (light-receiving elements) such as CCD elements (charge-coupled devices) or CMOS elements (complementary metal-oxide-semiconductor devices) arranged in a two-dimensional array, and a light-receiving surface capable of receiving light from outside the housing is arranged on the imaging unit side. Figure 3As shown, when the outer surface of the plate 7 constituting the reading port 5 is taken as the reading surface 7a, the first imaging unit 25a is mounted on the substrate with its field of view center La approximately orthogonal to the reading surface 7a so that it can receive incident light that passes through the first imaging unit 27a and enters the light-receiving surface. Similarly, the second imaging unit 25b is mounted side by side with the first imaging unit 25a on the same substrate with its field of view center Lb approximately orthogonal to the reading surface 7a so that it can receive incident light that passes through the second imaging unit 27b and enters the light-receiving surface.

[0087] The first imaging unit 27a is an imaging optical system composed of a known imaging lens. It is configured to define the shooting range (field of view) that the first imaging unit 25a can capture, and to guide light entering from outside the housing 3 through the readout 5 to the first imaging unit 25a. It functions to image an information code or the like when such a code is positioned outside the housing 3 within the shooting range. The second imaging unit 27b is an imaging optical system similarly configured to define the shooting range that the second imaging unit 25b can capture, and to guide light entering from outside the housing 3 through the readout 5 to the second imaging unit 25b. It functions to image an information code or the like when such a code is positioned outside the housing 3 within the shooting range. Furthermore, wide-angle lenses with short focal lengths and wide field of view are preferably used for both the first imaging unit 27a and the second imaging unit 27b.

[0088] like Figure 3 As shown, a filter (hereinafter also referred to as a visible light cutoff filter 29) that transmits infrared light but does not transmit visible light is disposed between the light-receiving surface of the second imaging unit 25b and the second imaging unit 27b, corresponding to the imaging range of the second imaging unit 25b. Therefore, even in outdoor environments where the surrounding visible light is too bright, the second imaging unit 25b can capture images of its subject based on the reflected light from the subject generated by the infrared light irradiation, without being affected by the surrounding visible light.

[0089] In addition, the information code reading device 1 includes an operation unit 33, a speaker 34, a light-emitting unit 35, and a communication interface 36. The operation unit 33 has one or more buttons provided on the outer surface of the housing 3, and is configured to send operation signals to the control unit 31 based on user button operations. The control unit 31 is configured to perform the corresponding action when it receives an operation signal from the operation unit 33. The speaker 34 is configured as a voice unit, such as a known speaker, and is configured to emit various sounds, such as preset sounds or alarm sounds, based on the operation signal from the control unit 31. The light-emitting unit 35 is, for example, an LED, and is configured to illuminate based on a signal from the control unit 31. The communication interface 36 is configured as an interface for data communication with external devices such as higher-level devices, and is configured to perform communication processing in conjunction with the control unit 31.

[0090] Next, the information code C, which is the object of reading the information code reading device 1 configured as described above, and the reading process performed in the control unit 31 when reading the information code C will be explained.

[0091] In this embodiment, the information code C that is to be read includes not only the usual barcode or QR code printed on paper media, but also information codes with enhanced security (hereinafter also referred to as information code Ca) or information codes displayed on the display screen of a portable terminal (hereinafter also referred to as information code Cb).

[0092] First, refer to Figure 6 The improved security of the information code Ca is explained.

[0093] The information code Ca involved in this embodiment is configured such that at least a portion of its code area is covered by a coating portion that does not transmit visible light but transmits infrared light, thereby improving security and enabling it to be used for purposes such as determining authenticity. Figure 6 (A) is an image of information code Ca taken in a normal environment illuminated by visible light (the first image will be described later). Figure 6 As can be seen from (A), the information code Ca is printed on a paper medium, etc., and has a code area Ca1 and a coating Ca2 that covers the entire code area Ca1.

[0094] Figure 6 (B) is from Figure 6 The image taken by removing the Ca2 coating in (A) (the second image, which will be described later), is from... Figure 6As shown in (B), the code region Ca1, like the QR code, is matrix-arranged with multiple bright-colored modules (bright-colored code elements) forming a square area and dark-colored modules (dark-colored code elements). The entire code region Ca1 is a rectangular area. In addition, three position detection patterns FPa are arranged at the three corners of the code region Ca1 as specific patterns of a predetermined number.

[0095] In the code region Ca1 constructed in this way, each bright-colored module is configured to exhibit bright reflective properties when illuminated by visible light or infrared light (light in the second wavelength band). Conversely, each dark-colored module is configured to exhibit dark reflective properties when illuminated by visible light or infrared light. Specifically, each module constituting the code region Ca1 is coated with a commonly used ink.

[0096] Furthermore, the Ca2 coating is formed by coating an ink that transmits reflected light from the modules constituting the code region Ca1 when irradiated with infrared light (light in the second wavelength band), but does not transmit visible light, such as infrared-transmitting ink. Therefore, under normal conditions where visible light dominates, from... Figure 6 As can be seen from (A), the code region Ca1 is completely hidden by the coating layer Ca2.

[0097] When photographing the information code Ca constructed in this way under visible light illumination, such as... Figure 6 As shown in (A), the coated portion Ca2 is captured based on reflected light from it, but the code region Ca1 cannot be captured. On the other hand, when capturing the information code Ca under infrared light illumination, the reflected light from the code region Ca1 generated by the infrared light transmission passes through the coated portion Ca2, as shown in (A). Figure 6 As shown in (B), the code area Ca1 can be captured. That is, in a conventional reading device where infrared light cannot be emitted, not only can the information code Ca not be captured, but the code area Ca1 cannot even be seen, thereby improving the security of the information code Ca. In particular, by employing a visible light cutoff filter 29, even in outdoor environments where the surrounding visible light is too bright, the code area Ca1 can be clearly captured because it is not affected by reflected light from the coating portion Ca2.

[0098] Next, refer to Figure 7 The information code Cb displayed on the display screen of the portable terminal is explained.

[0099] The information code Cb in this embodiment is configured as a QR code displayed on a screen, with three position detection patterns FPb arranged in specific patterns at the three corners of its code area as a predetermined number. This information code Cb is displayed on a screen using visible light, therefore, in the first imaging unit 25a which does not employ a visible light cutoff filter 29, it is possible to capture images as shown... Figure 7The image shown in (A) is the first image to be described later. On the other hand, in the second imaging unit 25b employing the visible light cutoff filter 29, an image is captured as shown... Figure 7 The image shown in (B) is a black screen (the second image, which will be described later), and the information code Cb could not be captured.

[0100] Therefore, in the reading process performed by the control unit 31 in this embodiment, the information code Cb is interpreted based on the image captured by the first imaging unit 25a (hereinafter also referred to as the first image), and the information code Ca is interpreted based on the image captured by the second imaging unit 25b (hereinafter also referred to as the second image). When the information code Ca is the subject of the image capture, such as... Figure 6 The first image was captured as shown in (A), and as shown in (A). Figure 6 As shown in (B), a second image is captured. If the information code Cb is the subject of the image capture, then... Figure 7 The first image was captured as shown in (A), and as shown in (A). Figure 7 The second image was taken as shown in (B).

[0101] Next, use Figure 8 The flowchart shown provides a detailed explanation of the read processing performed by the control unit 31 (i.e., CPU 31A).

[0102] When the control unit 31 begins reading and processing according to the prescribed operations of the operation unit 33, it executes... Figure 8 The irradiation process shown in step S101 involves irradiating visible light from the first illumination units 21a to 24a and irradiating infrared light from the second illumination units 21b to 24b. That is, both visible light and infrared light are irradiated simultaneously. Thus, as... Figure 5 As shown, the illumination light emanating from each of the first illumination units 21a to 24a and each of the second illumination units 21b to 24b illuminates the reflective surface of the light guide member 50, which is configured as a cone, and the reflective units 51 to 54 become brighter as a whole.

[0103] Next, the shooting process shown in step S103 is executed, including processing for acquiring a first captured image from the first shooting unit 25a and processing for acquiring a second captured image from the second shooting unit 25b.

[0104] Next, the extraction process shown in step S105 is performed. In this process, image parsing processing for extracting the position detection pattern from the specific pattern that serves as the information code in the first captured image is performed, and image parsing processing for extracting the position detection pattern from the specific pattern that serves as the information code in the second captured image is also performed.

[0105] Then, in the determination process of step S107, it is determined whether the subject has been captured based on the result of the above extraction process. Here, if no three position detection patterns are extracted from the first captured image and the second captured image, it is determined that no subject has been captured (step S107 is "No"), and the process starting from step S101 is executed.

[0106] On the other hand, if three position detection patterns are extracted from either the first or second captured image, the image is considered captured and is determined to be "yes" in step S107. In this case, during the determination process in step S109, it is determined whether the number of position detection patterns Na1 extracted from the first captured image is greater than or equal to the number of position detection patterns Na2 extracted from the second captured image.

[0107] Here, in the case of capturing the information code Cb displayed on the screen, such as Figure 7 As shown in (A), the first image is captured by the first imaging unit 25a, and as shown in (A). Figure 7 As shown in (B), the second image is captured by the second imaging unit 25b. Therefore, the number of extractions Na1 is greater than or equal to the number of extractions Na2, and in step S109, it is determined to be "yes", and the first image is set as the object of interpretation. Then, the first interpretation process in step S111 is performed, based on the first image set as the object of interpretation ( Figure 7 (A)) Decipher (decode) information code Cb.

[0108] Then, if the interpretation is successful (step S115 is "yes"), the notification processing shown in step S117 is executed, and the interpretation result is sent to the upper-level device through the communication interface 36.

[0109] Furthermore, when photographing a regular QR code printed on paper or other media, three position detection patterns are extracted from the first and second images, respectively, with the extraction count Na1 equal to the extraction count Na2. In this case, step S109 is also determined to be "yes," the first image is set as the object to be interpreted, and the processing after step S111 is performed.

[0110] Additionally, in the case of photographing information code Ca, such as Figure 6 As shown in (A), the first image is captured by the first imaging unit 25a, and as shown in (A). Figure 6 As shown in (B), the second image is captured by the second imaging unit 25b. Therefore, the number of extractions Na1 is less than the number of extractions Na2, and in step S109, it is determined to be "No," and the second image is set as the object of interpretation. Then, the second interpretation process in step S113 is performed, based on the second image set as the object of interpretation (…). Figure 6The information code Ca is decoded (decoded). Then, if the decoding is successful (step S115 is "Yes"), the notification processing shown in step S117 is executed, and the decoding result is sent to the upper-level device through the communication interface 36. In addition, the control unit 31 that performs the determination processing as described in step S109 above, which sets either the first captured image or the second captured image as the decoding object based on the result of the parsing processing of the first captured image and the second captured image, can be equivalent to an example of a "setting unit". In addition, the control unit 31 that performs the first decoding processing and the second decoding processing can be equivalent to an example of a "processing unit".

[0111] As described above, in the information code reading device 1 according to this embodiment, the first imaging unit 25a captures the information code when the first illumination units 21a to 24a illuminate visible light, and the second imaging unit 25b captures the information code when the second illumination units 21b to 24b illuminate infrared light (light in the second wavelength band). Furthermore, a visible light cutoff filter 29 that does not transmit visible light but transmits infrared light is provided corresponding to the imaging range of the second imaging unit 25b.

[0112] Therefore, if the object to be read is information code Ca, which is covered by a coating layer Ca2 in code region Ca1, the reflected light from code region Ca1 generated by irradiating infrared light passes through the coating layer Ca2. Thus, information code Ca can be interpreted based on a second captured image taken by the second imaging unit 25b. In particular, a visible light cutoff filter 29 that transmits infrared light but not visible light is provided within the imaging range of the second imaging unit 25b. Therefore, even in outdoor environments where the surrounding visible light is too bright, reflected light from the coating layer Ca2 will not be captured. On the other hand, if the object to be read is information code Cb displayed on a liquid crystal screen or the like, information code Cb can be interpreted based on a first captured image taken by the first imaging unit 25a. Thus, not only can information code Ca, which is covered by a coating layer Ca2 that cannot transmit visible light, be readablely captured, but information code Cb displayed on a screen can also be readablely captured.

[0113] In addition, in this embodiment, the control unit 31, which functions as an illumination control unit, controls each of the first illumination units 21a to 24a to irradiate visible light when the first imaging unit 25a takes a picture, and controls each of the second illumination units 21b to 24b to irradiate infrared light when the second imaging unit 25b takes a picture.

[0114] Therefore, in the case where the first imaging unit 25a and the second imaging unit 25b capture images at the same time point as in this embodiment, visible light and infrared light can be simultaneously irradiated. Furthermore, unlike this embodiment, when the first imaging unit 25a and the second imaging unit 25b capture images at different time points, the irradiation times of visible light and infrared light can be staggered to match their timing. For example, a first image can be captured using the first imaging unit 25a while each of the first illumination units 21a-24a irradiates visible light and no infrared light is irradiated by each of the second illumination units 21b-24b, and then a second image can be captured using the second imaging unit 25b while each of the second illumination units 21b-24b irradiates infrared light and no visible light is irradiated by each of the first illumination units 21a-24a.

[0115] In particular, during the reading process, processing is performed to extract position detection patterns (specific patterns) within the code area from the first captured image and the second captured image respectively, and the captured image with the larger number of extracted position detection patterns is set as the reading object.

[0116] There is a possibility that if the captured image is interpretable, it will be captured containing all position detection patterns; if the captured image is uninterpretable or difficult to interpret, it will be captured without containing all position detection patterns. Therefore, by defining the interpretation target based on the number of position detection patterns extracted as specific patterns, the interpretation target can be easily defined, thus further reducing the processing load related to interpretation. Furthermore, the interpretation target can also be defined based on the number of extracted specific patterns other than position detection patterns.

[0117] [Second Implementation]

[0118] Next, with reference to the accompanying drawings, the information code reading device according to the second embodiment of the present invention will be described.

[0119] In this second embodiment, the main difference from the first embodiment described above is that, during the reading process, either of the two captured images is designated as the object of interpretation based on the number of black-and-white changes in specific regions of both the first and second captured images. Therefore, structural parts that are substantially the same as those in the first embodiment are given the same labels, and their descriptions are omitted.

[0120] If an image is captured by defining a portion of the area in the captured image where the information code is easily captured as the aforementioned specific region, and thus the information code is captured in a way that allows for interpretation, then the specific region is likely to contain multiple bright and dark code elements arranged in sequence. Therefore, the number of black-and-white variations when binarizing this specific region of the captured image is greater than in a specific region of an image where the information code was not captured. Here, the number of black-and-white variations refers to the number of locations along one or more scan lines drawn within the specific region of the captured image where black and white variations occur. On the other hand, if the number of black-and-white variations along each scan line within the aforementioned specific region is low, there is a possibility that the information code was captured in a way that makes it uninterpretable or difficult to interpret.

[0121] Therefore, in this embodiment, the regions at the same positions in the first and second captured images are extracted as specific regions S. The extracted specific regions S are binarized, and processing is performed to count the number of black and white changes within the specific regions S. The captured images with more changes are set as the interpretation objects.

[0122] Next, use Figure 9 The flowchart shown provides a detailed explanation of the read processing performed by the control unit 31 (i.e., CPU 31A) in this embodiment.

[0123] Similar to the first embodiment described above, in the state where visible light is irradiated from the first illumination units 21a to 24a and infrared light is irradiated from the second illumination units 21b to 24b ( Figure 9 In step S101), processing for acquiring a first captured image from the first imaging unit 25a is performed, and processing for acquiring a second captured image from the second imaging unit 25b is performed (S103).

[0124] Next, the black-and-white variation count processing shown in step S105a is performed. In this processing, a specific region S is extracted from both the first and second captured images. The number of black-and-white variations within the specific region S in the first captured image is counted as the black-and-white variation number Nb1, and the number of black-and-white variations within the specific region S in the second captured image is counted as the black-and-white variation number Nb2. Furthermore, in this embodiment, to reduce the workload associated with the black-and-white variation count processing, the central portion of the captured image is extracted as the specific region S. This is because, in the case of capturing an information code, the information code is likely to be located in the central portion of the captured image.

[0125] Then, in the determination process of step S107a, it is determined whether the subject has been captured based on the black-and-white change count as described above. Here, if the black-and-white change count Nb1 of the first captured image and the black-and-white change count Nb2 of the second captured image are both less than a predetermined number, it is determined that the subject has not been captured ("No" in step S107a), and the process starting from step S101 above is executed.

[0126] On the other hand, if at least one of the black-and-white variation number Nb1 of the first captured image and the black-and-white variation number Nb2 of the second captured image is greater than or equal to the aforementioned predetermined number, then the image is considered captured as a subject, and step S107a determines that "yes". In this case, in the determination process of step S109a, it is determined whether the black-and-white variation number Nb1 of the first captured image is greater than or equal to the black-and-white variation number Nb2 of the second captured image.

[0127] Here, in the case of capturing the information code Cb displayed on the screen, such as Figure 11 As shown in (A), the number of black-and-white variations Nb1 within a specific region S of the first captured image captured by the first imaging unit 25a is counted, and as shown in (A), Figure 11 (B) shows the number of black-and-white changes Nb2 within a specific region S of the second captured image captured by the second capturing unit 25b. Therefore, if the number of black-and-white changes Nb1 is greater than or equal to the number of black-and-white changes Nb2, it is determined to be "yes" in step S109a, the first captured image is set as the object of interpretation, and the processing after step S111 is performed.

[0128] Additionally, in the case of photographing information code Ca, such as Figure 10 As shown in (A), the number of black-and-white variations Nb1 within a specific region S of the first captured image captured by the first imaging unit 25a is counted, and as shown in (A), Figure 10 (B) shows the number of black-and-white changes Nb2 within a specific region S of the second captured image captured by the second imaging unit 25b. Therefore, the number of black-and-white changes Nb1 is less than the number of black-and-white changes Nb2, and in step S109a, it is determined to be "no", the second captured image is set as the object of interpretation, and the processing after step S113 is performed.

[0129] As described above, in the information code reading device 1 according to this embodiment, a specific region S in each of the first captured image and the second captured image is binarized, and a process is performed to count the number of black-and-white changes Nb1 and Nb2 along one or more scan lines in the specific region S, and the captured image with the larger number of changes is set as the object to be read.

[0130] In this way, by setting the interpretation object based on the number of black and white changes within a specific region S, the interpretation object can be easily set, which can further reduce the processing load related to interpretation processing.

[0131] [Third Implementation Method]

[0132] Next, refer to Figure 12 The information code reading device according to the third embodiment of the present invention will be described.

[0133] In this third embodiment, the main difference from the first embodiment described above is the adoption of an infrared light cutoff filter. Therefore, structural parts that are substantially the same as those in the first embodiment are given the same reference numerals, and descriptions are omitted.

[0134] Infrared light has a longer wavelength than visible light. Therefore, when the first imaging unit 25a captures the first image while simultaneously irradiated with both infrared and visible light, the reflected light from the infrared light has a significant impact, which may cause blurring and prevent the clear capture of the information code.

[0135] Therefore, in this embodiment, as Figure 12 As shown, between the light-receiving surface of the first imaging unit 25a and the first imaging unit 27a, a separate filter (hereinafter also referred to as infrared light cut-off filter 29a) is arranged corresponding to the imaging range of the first imaging unit 25a. This filter does not transmit infrared light (light in the second wavelength band) but transmits visible light.

[0136] Therefore, when the first imaging unit 25a captures the information code under visible light, even if infrared light is irradiated by each of the second illumination units 21b to 24b, the first imaging unit 25a will not capture the reflected light generated by the infrared light. Thus, the influence of the infrared light can be eliminated, and the information code can be captured more clearly.

[0137] Furthermore, the infrared light cutoff filter 29a is not limited to being disposed between the light-receiving surface of the first imaging unit 25a and the first imaging unit 27a, but can also be disposed on the reading surface side of the first imaging unit 27a. Similarly, the visible light cutoff filter 29 is not limited to being disposed between the light-receiving surface of the second imaging unit 25b and the second imaging unit 27b, but can also be disposed on the reading surface side of the second imaging unit 27b. In addition, the feature structure of the infrared light cutoff filter 29a newly adopted in this embodiment can also be applied to other embodiments.

[0138] [Fourth Implementation Method]

[0139] Next, refer to Figure 13 The information code reading device according to the fourth embodiment of the present invention will be described.

[0140] In this fourth embodiment, the main difference from the first embodiment described above is that the first imaging unit 25a and the second imaging unit 25b are configured such that their centers of view intersect on the reading surface 7a. Therefore, structural parts that are substantially the same as those in the first embodiment are given the same reference numerals, and descriptions are omitted.

[0141] As described in the first embodiment above, when the first imaging unit 25a and the second imaging unit 25b are simply arranged within the housing 3, and their respective field-of-view centers La and Lb are orthogonal to the reading surface 7a (refer to...). Figure 3 The first imaging unit 25a and the second imaging unit 25b have different imaging ranges on the reading surface 7a. Therefore, the optimal position of the reading surface 7a when scanning information code Ca is different from the optimal position of the reading surface 7a when scanning information code Cb displayed on the screen.

[0142] Therefore, in this embodiment, as Figure 13 As shown, the first imaging unit 25a and the second imaging unit 25b, along with the first imaging unit 27a and the second imaging unit 27b, are housed within a housing 3 that has a reading surface 7a. They are configured such that the center of the field of view La of the first imaging unit 25a and the center of the field of view Lb of the second imaging unit 25b intersect at the center of the reading surface 7a, enabling the imaging of information codes scanned on the reading surface 7a. Therefore, in this embodiment, as... Figure 13 As shown, the substrate on which the first imaging unit 25a is mounted and the substrate on which the second imaging unit 25b is mounted are arranged in a state that is tilted in accordance with the angle between the center of the field of view La and the center of the field of view Lb.

[0143] In this way, by arranging the first imaging unit 25a and the second imaging unit 25b such that their respective field of view centers La and Lb intersect in the center of the reading surface 7a where the information code is easy to scan, the position of the optimal reading surface 7a when scanning the information code Ca can be made to coincide with the position of the optimal reading surface 7a when scanning the information code Cb in the center of the reading surface 7a.

[0144] In addition, such as Figure 14 In the illustrated variation, the first imaging unit 27a and the second imaging unit 27b can be configured such that they are eccentric relative to the first imaging unit 25a and the second imaging unit 25b mounted on the same substrate, so that the field of view center La of the first imaging unit 25a and the field of view center Lb of the second imaging unit 25b intersect at the center of the reading surface 7a. Thus, the feature structure in this embodiment and its variations, which arranges the first imaging unit 25a and the second imaging unit 25b such that their field of view centers intersect on the reading surface 7a, can also be applied to other embodiments.

[0145] [Fifth Implementation]

[0146] Next, with reference to the accompanying drawings, the information code reading device according to the fifth embodiment of the present invention will be described.

[0147] In this fifth embodiment, similar to the first embodiment described above, it includes a first illumination unit that illuminates visible light, a second illumination unit that illuminates light in the second wavelength band, a first imaging unit, and a second imaging unit that is equipped with a visible light cutoff filter within the imaging range. The main difference from the first embodiment is that it is configured in a different manner, such as with an optical configuration structure.

[0148] Specifically, such as Figure 15 As shown, the information code reading device 100 according to this embodiment is a fixed reading device mounted on the upper surface of a table or shelf, etc., and is configured to not only optically read display information (optical information) such as information codes or text information displayed on the photographed object, but also to save the photographed image of the object. In this embodiment, the information code and the display medium are the photographed object, and the display medium displays prescribed text information in a specific text format such as a passport on the display surface. Therefore, the information code reading device 100 is configured to have both the function of an information code reader for reading information codes and the known mark recognition processing function (OCR) for recognizing the photographed text information.

[0149] The information code reading device 100 has a generally box-shaped housing 103, which is formed of a resin material such as ABS resin to form the outer shape of the information code reading device 100. In addition, the main basic electrical structure of the information code reading device 100 is the same as that of the information code reading device 1 described above, and is configured to include a control unit 31, a memory 32, an operation unit 33, a speaker 34, a light-emitting unit 35, a communication interface 36, etc.

[0150] like Figure 15 as well as Figure 16 As shown, a reading surface 114, serving as a light inlet / outlet, is optically formed on the upper surface 103a of the housing 103, through a light-transmitting protective plate 116 (which will be described later). This reading surface 114, acting as an optical reading port, is formed into a rectangular opening. Light from outside the housing enters through the reading surface 114, and light from inside the housing exits. Furthermore, a light-receiving optical system, consisting of a first imaging unit and a second imaging unit, functions to capture images of the display medium scanned on this reading surface 114.

[0151] The upper surface 103a of the housing 103 is composed of a reading surface 114 and a strip-shaped end 115 connected to the edge 114a of the reading surface 114, and is protected by a protective plate 116 in a manner that closes the reading port. The protective plate 116 is configured as a flat plate of a specified thickness and is made of a light-transmitting material (e.g., transparent acrylic resin or transparent glass) that allows light from both the outside and inside of the housing to pass through.

[0152] Of the four sides of the reading surface 114, the side 114b opposite to side 114a corresponds to one edge of the upper surface 103a of the housing 103. The other two sides 114c and 114d of the four sides of the reading surface 114 also correspond to the other edges of the upper surface 103a of the housing 103.

[0153] Next, the light-projecting optical system and the light-receiving optical system of the information code reading device 100 will be described.

[0154] like Figures 17 to 19 As shown, the light-projecting optical system in this embodiment includes a first illumination unit 121a and a second illumination unit 121b, a louver 140, and a reflective component 150. The first illumination unit 121a and the second illumination unit 121b function as surface light sources capable of illuminating uniform light. The first illumination unit 121a, as a surface light source, is configured to illuminate uniform visible light. The second illumination unit 121b, as a surface light source, is configured to illuminate uniform light in a second wavelength band, specifically infrared light. The illumination state of the first illumination unit 121a and the second illumination unit 121b can be controlled by a control unit 31, which functions as an illumination control unit. The first illumination unit 121a and the second illumination unit 121b are positioned below an end 115 and are configured to illuminate visible light and infrared light towards the reflective component 150 through the louver 140. Thus, since the first lighting unit 121a and the second lighting unit 121b use surface light sources, even when light passes through the louver 140, uneven illuminance distribution on the reflective component 150 that emits illumination light (visible light and infrared light) can be suppressed. Furthermore, in Figure 17 In the diagram, the visible light emitted from the first illumination unit 121a is illustrated as illumination light Lfa, and the infrared light emitted from the second illumination unit 121b is illustrated as illumination light Lfb.

[0155] like Figure 17 as well as Figure 18As shown, the venetian blind 140 is located on the illumination side of the first illumination unit 121a and the second illumination unit 121b, and is configured such that each slat 141 extends relative to a plane parallel to the reading surface 114. Specifically, each slat 141 is configured to be parallel to the reading surface 114. The venetian blind 140 functions to ensure that the illumination direction of visible light from the first illumination unit 121a and the illumination direction of infrared light from the second illumination unit 121b are substantially parallel to the reading surface 114 through each slat 141.

[0156] The reflective component 150 is disposed inside the housing 103 at a position where illumination light (visible light and infrared light) is irradiated through the louvers 140, and outside the first pre-reflection imaging range AR1a and the second pre-reflection imaging range AR2a (described later), configured to guide the illumination light through the reading surface 114 to irradiate the outside of the housing 103. The reflective component 150 includes a reflective portion 151, a reflective portion 152, and a reflective portion 153. Figure 17 as well as Figure 18 As shown, the reflective portion 151 is formed such that its upper end extends towards the reading surface 114, and it curves outward in a recessed manner. Furthermore, as... Figure 19 As shown, the reflective portion 152 is formed with its upper end extending towards the reading surface 114 as an edge 114c, and then bends outward. Similarly, the reflective portion 153 is formed with its upper end extending towards the reading surface 114 as an edge 114d, and then bends outward. Furthermore, an opening 154 is formed at the lower end of the reflective portions 151, etc., to expose the imaging portion, etc.

[0157] The light-receiving optical system in this embodiment has the same function as the light-receiving optical system in the first embodiment described above, and is composed of two imaging units (hereinafter also referred to as the first imaging unit 125a and the second imaging unit 125b), two imaging units (hereinafter also referred to as the first imaging unit 127a and the second imaging unit 127b), a visible light cutoff filter 129, etc. Figure 17 As shown, the first imaging unit 125a is mounted on the substrate to receive incident light that passes through the reading surface 114 and then through the first imaging unit 127a to enter its light-receiving surface. Additionally, as... Figure 18 As shown, the second imaging unit 125b is mounted on the substrate so as to receive incident light that passes through the reading surface 114 and then through the second imaging unit 127b and the visible light cutoff filter 129 to enter its light-receiving surface.

[0158] The first imaging unit 127a is configured to define a first imaging range that the first imaging unit 125a can capture, and to guide light entering from outside the housing 103 through the reading surface 114 to the first imaging unit 125a. This allows the first imaging unit 125a to image an image of an information code or similar object located within the first imaging range outside the housing 103. The second imaging unit 127b is configured to define a second imaging range that the second imaging unit 125b can capture, and to guide light entering from outside the housing 103 through the reading surface 114 to the second imaging unit 125b. This allows the second imaging unit 125b to image an image of an information code or similar object located within the second imaging range outside the housing 103. Furthermore, wide-angle lenses with short focal lengths and wide field of view are preferably used, for example, as the first imaging unit 127a and the second imaging unit 127b.

[0159] like Figure 18 as well as Figure 19 As shown, a visible light cutoff filter 129 that transmits infrared light but does not transmit visible light is disposed between the light-receiving surface of the second imaging unit 125b and the second imaging unit 127b, corresponding to the imaging range of the second imaging unit 125b. Therefore, even in outdoor environments where the surrounding visible light is too bright, the second imaging unit 125b can capture the subject based on the reflected light from the subject generated by the infrared light irradiation, without being affected by the surrounding visible light.

[0160] In particular, in this embodiment, such as Figure 17 As shown, the area formed between the first imaging unit 127a and the reading surface 114 within the aforementioned first imaging range is designated as the first pre-reflection imaging range AR1a. The area formed between the reading surface 114 and the reflecting member 150, connected to the first pre-reflection imaging range AR1a when reflected inwards from the reading surface 114 via the protective plate 116, is designated as the first post-reflection imaging range AR1b. In this case, the first imaging unit 127a is configured such that each reflecting part 151 to 153 is located outside the first pre-reflection imaging range AR1a. Furthermore, as... Figure 18As shown, the area formed between the second imaging unit 127b and the reading surface 114 within the second imaging range is designated as the second pre-reflection imaging range AR2a. The area formed between the reading surface 114 and the reflective member 150, connected to the second pre-reflection imaging range AR2a when reflected from the reading surface 114 by the protective plate 116, is designated as the second post-reflection imaging range AR2b. In this case, the second imaging unit 127b is configured such that each reflective part 151 to 153 is located outside the second pre-reflection imaging range AR2a. That is, the reflective member 150 is positioned outside both the first pre-reflection imaging range AR1a and the second pre-reflection imaging range AR2a. Furthermore, to suppress projection onto the captured image, the first illumination unit 121a and the second illumination unit 121b, the venetian blind 140, the first imaging unit 125a and the second imaging unit 125b, and the first imaging unit 127a and the second imaging unit 127b are positioned outside both the first post-reflection imaging range AR1b and the second post-reflection imaging range AR2b.

[0161] Furthermore, in order to suppress the influence of visible light projection onto the captured image, the first illumination unit 121a is configured to illuminate visible light toward the first reflective surface 155a of each of the reflective units 151-153, which serves as the first reflection and capture range AR1b, in such a way that the illuminance distribution on the first reflective surface 155a is approximately uniform (see reference). Figure 17 Similarly, in order to suppress the influence of infrared light projected into the captured image, the second illumination unit 121b is configured to illuminate infrared light toward the second reflective surface 155b of each of the reflective units 151-153, which serves as the second reflection and capture range AR2b, in such a way that the illuminance distribution on the second reflective surface 155b is approximately uniform (see reference). Figure 18 ).

[0162] In the information code reading device 100 configured in this way, for example, when reading the information code Cb displayed on the display screen of a portable terminal, the display screen is captured by the first imaging unit 125a and the second imaging unit 125b while being illuminated by visible light and infrared light reflected by the reflective member 150. In this case, the determination process in step S109 is determined to be "yes", and the information code Cb is interpreted based on the first captured image captured by the first imaging unit 125a.

[0163] At this time, the first shooting range includes the first reflection shooting range AR1b, which is closer to the inner side of the housing than the reading surface 114 (protective plate 116) due to the reflection of the protective plate 116. As a result, not only the display screen of the portable terminal, but also the first reflective surface 155a and the second reflective surface 155b of the reflective component 150 are slightly projected into the first captured image. Since the illumination light (visible light and infrared light) is irradiated on the first reflective surface 155a and the second reflective surface 155b in a manner with a substantially uniform illuminance distribution, for example, compared to the case where the illuminance distribution is uneven and there are areas with large illuminance in the first reflective surface 155a and the second reflective surface 155b, the required illuminance in the captured image can be ensured and the illumination light is not highlighted.

[0164] Furthermore, for example, when reading information code Ca printed on a paper medium, the paper medium is photographed by the first imaging unit 125a and the second imaging unit 125b while being irradiated with visible light and infrared light reflected by the reflective member 150. In this case, the determination process in step S109 above determines "No", and the information code Ca is interpreted based on the second image captured by the second imaging unit 125b.

[0165] At this time, the second imaging range includes the second reflection imaging range AR2b, which is further inside the housing than the reading surface 114 due to the reflection of the protective plate 116. As a result, not only paper media, but also the first reflective surface 155a and the second reflective surface 155b of the reflective member 150 are slightly projected into the second image. In this case, since the illumination light (visible light and infrared light) is irradiated on the first reflective surface 155a and the second reflective surface 155b in a manner with a substantially uniform illuminance distribution, the required illuminance in the image can be ensured without highlighting the illumination light.

[0166] As described above, the information code reading device 100 according to this embodiment is provided with a reflective member 150 that reflects visible light irradiated from the first illumination unit 121a and light of a second wavelength band irradiated from the second illumination unit 121b toward the reading surface 114. Furthermore, the reflective member 150 is positioned outside the first pre-reflection imaging range AR1a and outside the second pre-reflection imaging range AR2a, and the first illumination unit 121a, the second illumination unit 121b, the first imaging unit 125a, the second imaging unit 125b, and the visible light cutoff filter 129 are positioned outside the first post-reflection imaging range AR1b and outside the second post-reflection imaging range AR2b. Visible light is irradiated from the first illumination unit 121a toward the first reflective surface 155a of the reflective member 150, which serves as the first post-reflection imaging range AR1b, and light of a second wavelength band is irradiated from the second illumination unit 121b toward the second reflective surface 155b of the reflective member 150, which serves as the second post-reflection imaging range AR2b.

[0167] Therefore, when capturing an information code scanned on the reading surface 114, even if reflection from the display surface or the like causes a portion of the display code that is closer to the inside of the housing than the reading surface 114 to be projected into the captured image, it is easy to capture the entirety of the first reflective surface 155a of the reflective member 150 irradiated with visible light and the entirety of the second reflective surface 155b of the reflective member 150 irradiated with light of the second wavelength band. Therefore, compared to directly capturing the first illumination unit 121a and the second illumination unit 121b, the required illuminance in the captured image can be ensured and the illumination light (visible light and light of the second wavelength band) is not prominent, suppressing light noise generated by the illumination light. Therefore, even when the first illumination unit 121a and the second illumination unit 121b are housed within the housing, light noise generated by reflection of the illumination light affecting the captured image can be suppressed.

[0168] In particular, visible light is illuminated by the first illumination unit 121a in a manner that suppresses uneven illuminance distribution on the first reflective surface 155a, and light of the second wavelength band is illuminated by the second illumination unit 121b in a manner that suppresses uneven illuminance distribution on the second reflective surface 155b. Therefore, the illuminance distribution on either the first reflective surface 155a or the second reflective surface 155b tends to become more uniform, resulting in the illumination light being less prominent in the captured image. Thus, it is possible to reliably suppress light noise caused by reflection of the illumination light from affecting the captured image.

[0169] In addition, since the first illumination unit 121a and the second illumination unit 121b are surface light sources, they can illuminate the first reflective surface 155a or the second reflective surface 155b with approximately uniform illuminance, thereby improving the light noise suppression effect of using the first reflective surface 155a and the second reflective surface 155b.

[0170] In particular, louvers 140 are provided on the illumination sides of the first illumination unit 121a and the second illumination unit 121b, and each slat 141 of the louvers 140 is arranged parallel to the reading surface 114. As a result, light irradiated by the louvers 140 is difficult to directly escape through the reading surface 114 to the outside, thus easily suppressing specular reflections even on display surfaces that are scanned at an angle relative to the reading surface 114, enabling a structure that can tolerate scanning methods on rough display surfaces. Furthermore, the louvers 140 are not limited to being arranged so that each slat 141 is parallel to the reading surface 114; they can also be arranged so that each slat 141 is substantially parallel to the reading surface 114, that is, each slat 141 extends relative to a plane parallel to the reading surface 114.

[0171] Furthermore, to further improve the light noise suppression effect using the first reflective surface 155a or the second reflective surface 155b, the venetian blinds 140 can also be removed. Additionally, the characteristic structure of this embodiment can also be applied to other embodiments, etc.

[0172] [Sixth Implementation Method]

[0173] Next, with reference to the accompanying drawings, the information code reading device according to this sixth embodiment will be described.

[0174] In this sixth embodiment, the main difference from the fifth embodiment described above is that the louvers 140 are removed, and illumination light is irradiated in multiple directions in accordance with the shape of the light guide plate of the surface light source.

[0175] In this embodiment, such as Figure 20 As shown, the first illumination unit 121a, which functions as a surface light source, includes: a first light-emitting unit 201 and a second light-emitting unit 202, which emit visible light as illumination light; and a light guide plate 203 disposed between the first light-emitting unit 201 and the second light-emitting unit 202, on which light from the first light-emitting unit 201 is incident from a first side 204a, and light from the second light-emitting unit 202 is incident from a second side 204b. Furthermore, the light guide plate 203 has a plurality of grooves 206 inside, which reflect light incident from the first side 204a and the second side 204b toward the exit surface 205. The plurality of grooves 206 are asymmetrically formed such that the shape of the first side 206a (the side of the first side 204a) is different from the shape of the second side 206b (the side of the second side 204b).

[0176] Specifically, the groove 206 is formed as a curved surface with a large curvature on the first side surface 206a, therefore, as Figure 21 As exemplified in (A), light from the first side surface 204a illuminates the exit surface 205 in a direction that transmits through the first side surface 206a and the second side surface 206b. Furthermore, the second side surface 206b is formed with a planar portion or a slightly curved portion that is approximately planar, therefore... Figure 21 As exemplified in (B), light from the second side 204b illuminates the exit surface 205 in the direction of reflection from the second side 206b.

[0177] That is, the illumination direction of visible light (illumination light) illuminating the illumination surface can be divided into at least two directions: an illumination direction based on the shape of the first side surface 206a and an illumination direction based on the shape of the second side surface 206b. Therefore, by forming the first side surface 206a and the second side surface 206b of each groove 206 such that one illumination direction is directed towards the first reflecting surface 55a and the second reflecting surface 55b, and the other illumination direction is directed towards a predetermined range where insufficient illumination occurs on the reading surface 114, the illumination on the edge 114a side of the reading surface 114 near the first illumination unit 121a can be increased, and the reduction in ambient light around the first imaging unit 127a can be compensated.

[0178] In this way, compared to the case where the shapes of the first side surface 204a and the second side surface 204b of the plurality of slots 206 are respectively symmetrical, the illuminance distribution of the visible light (illumination light) emitted from the emission surface is prone to being uneven. That is, by changing the shape of the plurality of slots 206 according to the desired illuminance distribution of visible light, not only can visible light be irradiated in multiple directions through the emission surface, but its irradiation direction can also be controlled. For example, a portion of the visible light can be irradiated toward the first reflecting surface 55a and the second reflecting surface 55b, and another portion of the visible light can be irradiated toward the end side of the reading surface 114 where the ambient light intensity of the first imaging unit 127a decreases.

[0179] As a first variation of this embodiment, such as Figure 22 As shown in the example, the second light-emitting part 202 can also be removed. That is, in a variation of this embodiment, the first illumination part 121a is configured to include the first light-emitting part 201 and the light guide plate 203, wherein light from the first light-emitting part 201 is incident on the first side surface 204a of the light guide plate 203.

[0180] In this way, light incident from the first side surface 204a is reflected internally from the second side surface 204b towards the first side surface 204a, which easily leads to uneven illuminance distribution of visible light (illumination light) emitted from the exit surface. Therefore, by changing the shape of the multiple slots 206 according to the desired illuminance distribution of visible light, it is possible not only to illuminate visible light in multiple directions through the exit surface, but also to control the direction of illumination. In particular, since only the first light-emitting part 201 needs to be arranged on the first side surface 204a, there is no need to arrange the second light-emitting part 202 on the second side surface 204b, saving space in the first illumination part 121a and reducing the number of parts.

[0181] Furthermore, as a second variation of this embodiment, such as Figure 23 As exemplified, a reflector 207 can also be provided on the second side 204b where the second light-emitting part 202 has been removed. Consequently, light incident from the first side 204a is easily reflected inward from the second side 204b towards the first side 204a, thus improving reflection efficiency. This suppresses the transmission of some light incident from the first side 204a to the second side 204b due to the absence of the reflector 207, resulting in increased illuminance of visible light (illumination light) emanating in multiple directions through the outgoing surface.

[0182] Furthermore, in the first modification described above, the first light-emitting part 201 can be removed to replace the second light-emitting part 202. Additionally, in the second modification described above, the first light-emitting part 201 can be removed to replace the second light-emitting part 202, and a reflector 207 can be provided on the first side surface 204a. That is, the first illumination part 121a can also include a light-emitting part and a light guide plate 203. Light from the light-emitting part is incident on one side of the light guide plate 203. The light guide plate 203 has multiple grooves 206 inside that reflect the light incident from one side towards the exiting surface 205. When the side surface of the light guide plate 203 opposite to the aforementioned side surface is taken as the other side surface, these multiple grooves 206 are asymmetrically arranged so that the shape of the side surface is different from the shape of the side surface.

[0183] In this embodiment and its variations, the characteristic structure that illuminates light in multiple directions based on the shape of the light guide plate of the surface light source can be applied to the second illumination unit 121b, which functions as a surface light source.

[0184] [Seventh Implementation Method]

[0185] Next, with reference to the accompanying drawings, the information code reading device according to this seventh embodiment will be described.

[0186] In this seventh embodiment, the main difference from the fifth embodiment described above is that the reflection state of a portion of the reflective component is changed in order to reduce the effect of specular reflection.

[0187] The most significant difference in the information code reading device 100a described in this embodiment is that, instead of the reflective component 150, a reflective component 150a is used in the information code reading device 100. The reflective component 150a has a curved surface shape that is substantially the same as that of the reflective component 150, such as... Figure 24 as well as Figure 25 As shown, an opening 154a is provided at approximately the center when viewed from the reading surface 114 (upper side). A light-receiving optical system is provided, so that the first imaging part 127a and the second imaging part 127b are exposed as exposed parts through the opening 154a.

[0188] In particular, in this embodiment, from Figure 25 It can be seen that the annular edge forming the opening 154a (hereinafter also referred to as the opening edge) is formed in a reflective state, gradually becoming brighter from the inside to the outside.

[0189] The reason for forming the opening edge of opening 154a in this way will be explained below.

[0190] For example, when capturing information codes on a display screen scanned on the reading surface 114, there is a possibility that reflective components such as the reflective element 150a inside the housing 103 may be projected onto the captured image through the transparent protective plate 116 (reading surface 114) due to specular reflection. In this case, depending on the projection state, there is a possibility that the captured information code will fail to be decoded. When the first imaging unit 127a and the second imaging unit 127b are exposed within the reflective surface of the reflective element 150a, which, as described above, reflects illumination light toward the reading surface 114, the exposed portion does not have reflective properties, so the boundary between the exposed portion and the surrounding reflective portion becomes a range of abrupt contrast changes in the projected captured image. Specifically, the exposed portion is captured as black, and the surrounding reflective portion is captured as white, with the boundary between the two becoming a range of abrupt contrast changes between black and white. In the captured image that is to be decoded, when the range of abrupt contrast changes as described above overlaps with a portion of the code area in the information code where bright and dark code elements are arranged, the accuracy of the brightness determination of the code elements is reduced within the overlapping range, thus reducing the success rate of decoding the information code.

[0191] Therefore, in this embodiment, in order to suppress the decrease in the success rate of information code decoding caused by specular reflection, the opening edge of the opening 154a is formed such that the reflective state gradually brightens from the inside to the outside. Here, as a structure for realizing the above-mentioned change in the reflective state, for example, a color scheme structure in which the color of the opening edge of the reflective member 150a itself gradually changes from black to bright white from the inside to the outside can be adopted.

[0192] With this configuration, the reflective portion corresponding to the aforementioned opening edge becomes a range of gradually changing contrast (hereinafter also referred to as the gradient range) in the captured image projected as described above. Therefore, even if the aforementioned gradient range in the captured image overlaps with a portion of the code area in the information code where bright and dark colors are arranged, the accuracy of the brightness determination of the code elements is difficult to reduce, thus suppressing the decrease in the success rate of information code interpretation caused by specular reflection.

[0193] Furthermore, the structure used to achieve the aforementioned change in reflection state is not limited to a structure that changes the color of the opening edge of the reflective member 150a itself. For example, a structure that adjusts the reflectivity by surface processing of the opening edge of the reflective member 150a can also be used. Additionally, a separate covering member (e.g., a sealing member) can be prepared to cover the opening edge, and this covering member can be configured such that its reflection state gradually brightens from the inside to the outside. In this way, even if the covering member around the exposed portion (first imaging portion 127a and second imaging portion 127b) becomes a gradient range as described above in the projected image, the decrease in the success rate of information code decoding due to specular reflection can be suppressed. In particular, the contrast of the gradient range in the captured image can be easily adjusted by changing the covering member.

[0194] Furthermore, the aforementioned gradient range is not limited to the opening edge of the opening 154a exposed by the first imaging unit 127a and the second imaging unit 127b, but can also be provided at the opening edge of the opening that exposes other exposed parts such as screws disposed within the reflective surface of the reflective member 150a. Additionally, even in a structure using only one imaging unit instead of two, the gradient range can be provided at the opening edge of the opening that exposes a portion of the imaging unit, such as the imaging unit. In this way, the aforementioned other exposed parts also achieve the aforementioned effects. Furthermore, when multiple exposed parts are provided for the reflective member, the gradient range can also be provided for each of the exposed parts.

[0195] Furthermore, the aforementioned gradient range is not limited to being annular relative to the opening edge forming the opening 154a, but may also be provided in at least a portion of the opening edge.

[0196] In addition, the opening that exposes the exposed part is not limited to being located approximately in the center of the reflective component when viewed from the reading surface side; it can also be provided in a cut-out shape relative to the outer edge of the reflective surface.

[0197] As a variation of this embodiment, the peripheral portion of the exposed outer annular edge, when viewed from the reading surface side, can be formed in a reflective state, gradually brightening from the inside to the outside. If the structure exposes both first imaging units 127a and second imaging units 127b as described above, the peripheral portion of the peripheral portion of the outer annular edge of each of the first imaging units 127a and second imaging units 127b, when viewed from the reading surface side, can be formed in a reflective state, gradually brightening from the inside to the outside. Furthermore, for example, as... Figure 26 As an example, if an imaging section 127c is exposed from the opening 154c as an exposed portion, the peripheral portion of the outer annular edge of the imaging section 127c (see reference) Figure 26The cross-hatching area is formed into a reflective state that gradually brightens from the inside to the outside. As a result, the aforementioned gradient range is increased, including not only the opening edge of the opening 154c provided on the reflective member 150a, but also the periphery of the exposed portion. Therefore, the degree of brightness variation within the gradient range can be reduced, and the reduction in the success rate of information code decoding caused by specular reflection can be further suppressed.

[0198] Furthermore, the gradient range is not limited to being set at both the opening edge and the periphery of the exposed portion in the reflective member; it may also be set only at the periphery of the exposed portion. That is, when viewed from the reading surface side, the exposed portion is exposed through the opening provided on the reflective member, and the exposed portion is formed such that when viewed from the reading surface side, the reflection state of the periphery, which is an outer ring-shaped edge, gradually brightens from the inside to the outside.

[0199] In this way, the periphery becomes a gradually brightening range in the image projected as described above. Even if this gradually brightening range overlaps with a part of the code area in the information code where bright and dark code elements are arranged, the accuracy of the brightness and darkness determination of the code elements is difficult to reduce, and the success rate of information code interpretation caused by specular reflection can be suppressed.

[0200] [Eighth Implementation Method]

[0201] Next, with reference to the accompanying drawings, the information code reading device according to this eighth embodiment will be described.

[0202] In this eighth embodiment, the main difference from the first embodiment described above lies in the number of light-receiving sensors, etc., constituting the first and second imaging units. Therefore, structural parts that are substantially the same as those in the first embodiment are given the same reference numerals, and their descriptions are omitted.

[0203] The information code reading device 1a according to this embodiment is configured differently from the information code reading device 1 described above, mainly in the number of light-receiving sensors, etc., constituting the first and second imaging units. Specifically, as shown in... Figure 27 As shown, the first imaging unit 25a is configured to include a light-receiving sensor 61a and a light-receiving sensor 61b, and the first imaging unit 27a is configured to include an imaging lens 62a for imaging information codes, etc., on the light-receiving sensor 61a and an image imaging lens 62b for imaging information codes, etc., on the light-receiving sensor 61b. The aforementioned visible light cutoff filter 29 is not disposed between the light-receiving surface of the light-receiving sensor 61a and the imaging lens 62a, or between the light-receiving surface of the light-receiving sensor 61b and the imaging lens 62b.

[0204] In particular, the imaging lens 62a is configured to have its focal position set near the reading surface 7a, while the imaging lens 62b is different from the imaging lens 62a and is configured to have its focal position set at a position farther than the reading surface 7a (for example, a position approximately twice the distance to the reading surface 7a).

[0205] Therefore, for capturing information codes such as Cb displayed on a screen, two first-order images can be captured using a visible light receiving optical system 60a equipped with a light-receiving sensor 61a and an imaging lens 62a, and a visible light receiving optical system 60b equipped with a light-receiving sensor 61b and an imaging lens 62b. That is, by making the functions related to capturing the images in the visible light receiving optical system 60a and the light-receiving optical system 60b for capturing information codes such as Cb displayed on a screen different as described above, it is possible to capture images focused near the reading surface 7a and images focused at a position farther from the reading surface 7a. Furthermore, the light-receiving sensor 61a can be considered an example of "one light-receiving sensor," and the light-receiving optical system 60a can be considered an example of "one light-receiving optical system." Additionally, the light-receiving sensor 61b can be considered an example of "the other light-receiving sensor," and the light-receiving optical system 60b can be considered an example of "the other light-receiving optical system."

[0206] Furthermore, the second imaging unit 25b is configured to include a light-receiving sensor 61c and a light-receiving sensor 61d, and the second imaging unit 27b is configured to include an imaging lens 62c that captures an image of information codes, etc., on the light-receiving sensor 61c and an imaging lens 62d that captures an image of information codes, etc., on the light-receiving sensor 61d. The aforementioned visible light cutoff filter 29 is disposed between the light-receiving surface of the light-receiving sensor 61c and the imaging lens 62c, and between the light-receiving surface of the light-receiving sensor 61d and the imaging lens 62d.

[0207] In particular, the imaging lens 62c is configured to have its focal position set near the reading surface 7a, while the imaging lens 62d is different from the imaging lens 62c and is configured to have its focal position set at a position farther than the reading surface 7a (for example, a position approximately twice the distance to the reading surface).

[0208] Therefore, for capturing information codes such as the information code Ca, whose security is enhanced by the coating layer Ca2, two second images can be captured using an infrared light-receiving optical system 60c equipped with a light-receiving sensor 61c and an imaging lens 62c, and an infrared light-receiving optical system 60d equipped with a light-receiving sensor 61d and an imaging lens 62d. That is, the functions related to capturing are different in the infrared light-receiving optical system 60c and the light-receiving optical system 60d used for capturing information codes such as the information code Ca, whose security is enhanced by the coating layer Ca2. Furthermore, the light-receiving sensor 61c can be considered as one example of "one light-receiving sensor," and the light-receiving optical system 60c can be considered as one example of "one light-receiving optical system." Additionally, the light-receiving sensor 61d can be considered as one example of "the other light-receiving sensor," and the light-receiving optical system 60d can be considered as one example of "the other light-receiving optical system."

[0209] In the reading process executed by the control unit 31 (i.e., CPU 31A) in the information code reading device 1a configured in this way, when visible light is irradiated from the first illumination units 21a to 24a and infrared light is irradiated from the second illumination units 21b to 24b (S101), processing for acquiring a first captured image from the light-receiving sensor 61a and the light-receiving sensor 61b respectively is executed, and processing for acquiring a second captured image from the light-receiving sensor 61c and the light-receiving sensor 61d respectively is executed (S103).

[0210] At this time, when capturing the information code Cb displayed on the screen, as shown in the light sensor 61a and light sensor 61b... Figure 7 The first captured image is shown in (A). In particular, in the light-receiving optical system 60a with light-receiving sensor 61a, it is possible to focus relative to the information code Cb scanned near the reading surface 7a, and in the light-receiving optical system 60b with light-receiving sensor 61b, it is possible to focus relative to the information code Cb at a certain distance from the reading surface 7a. In this way, two first captured images with different focuses can be captured, which can improve the success rate of reading the information code Cb, etc., displayed on the screen.

[0211] On the other hand, when capturing the aforementioned information code Ca, in the light-receiving sensor 61c and light-receiving sensor 61d, as... Figure 6 The second image is captured as shown in (B). Specifically, in the light-receiving optical system 60c with light-receiving sensor 61c, it is possible to focus relative to the information code Ca scanned near the reading surface 7a; and in the light-receiving optical system 60d with light-receiving sensor 61d, it is possible to focus relative to the information code Ca displayed on the screen at a certain distance from the reading surface 7a. This allows for the capture of two second images with different focuses, improving the success rate of reading information codes Ca, etc., whose security is enhanced by the coating portion Ca2.

[0212] As described above, in the information code reading device 1a according to this embodiment, the first imaging unit 25a includes a light-receiving sensor 61a and a light-receiving sensor 61b, configured such that the imaging-related functions of the light-receiving optical system 60a with the light-receiving sensor 61a are different from those of the other light-receiving optical system 60b with the light-receiving sensor 61b. Therefore, even for ordinary information codes displayed on a liquid crystal screen or the like, two types of images can be captured based on the aforementioned different functions: an image captured by the light-receiving optical system 60a and an image captured by the light-receiving optical system 60b. Thus, even if the information code cannot be readable and measurable in the light-receiving optical system 60a, it can be readable and measurable in the light-receiving optical system 60b; conversely, even if the information code cannot be readable and measurable in the light-receiving optical system 60b, it can be readable and measurable in the light-receiving optical system 60a, thereby improving the success rate of information code decoding.

[0213] Furthermore, the second imaging unit 25b includes a light-receiving sensor 61c and a light-receiving sensor 61d, such that the imaging-related functions of the light-receiving optical system 60c with light-receiving sensor 61c are different from those of the light-receiving optical system 60d with light-receiving sensor 61d. Therefore, even if the code region C1a is covered by a coating portion Ca that transmits light in the second wavelength band, such as infrared light, but not visible light, two types of images can be captured: one captured by the light-receiving optical system 60c and the other by the light-receiving optical system 60d, depending on the aforementioned different functions. Therefore, even if the information code Ca cannot be readablely captured in the light-receiving optical system 60c, it can be readablely captured in the light-receiving optical system 60d; conversely, even if the information code Ca cannot be readablely captured in the light-receiving optical system 60d, it can be readablely captured in the light-receiving optical system 60c, thereby improving the success rate of information code decoding.

[0214] Furthermore, the light-receiving optical system for visible light is not limited to two light-receiving optical systems, 60a and 60b; three or more can be prepared. For example, as a first variation of this embodiment, it can also be as follows: Figure 28 The information code reading device 1b shown has three light-receiving optical systems prepared for the aforementioned information code reading device 1a: light-receiving optical system 60a, light-receiving optical system 60b, and a light-receiving optical system 60e for visible light. Similarly, the light-receiving optical system for infrared light is not limited to two light-receiving optical systems, light-receiving optical system 60c and light-receiving optical system 60d, and may include three or more.

[0215] Alternatively, two or more optical systems for receiving visible light and one optical system for receiving infrared light can be prepared. For example, as a second variation of this embodiment, it can also be as follows: Figure 29 The information code reading device 1c shown includes a light-receiving optical system 60a, a light-receiving optical system 60b, and a light-receiving optical system 60c, similar to the information code reading device 1a described above. Likewise, two or more light-receiving optical systems for infrared light and one light-receiving optical system for visible light can also be provided.

[0216] Furthermore, in multiple visible light receiving optical systems, the shooting-related functions of one receiving optical system that differ from the other are not limited to the functions corresponding to the adjustment of the focus position mentioned above; for example, they could also be functions corresponding to the adjustment of the viewing angle.

[0217] For example, by making the shooting-related functions different in that the viewing angle of the light-receiving optical system 60a is smaller than that of the light-receiving optical system 60b, the entire surface of the reading surface 7a in the light-receiving optical system 60b is used as the area for shooting information codes. Although the shooting field of view is narrowed in the light-receiving optical system 60a, even information codes with small code elements can be captured in a readable way.

[0218] Alternatively, for example, the functions related to image capture can be configured differently depending on the pixel count of the light-receiving sensor in one light-receiving optical system compared to the other. In this case, even if the light-receiving optical system with a wider field of view is used, it can still capture information codes with smaller code elements in a readable manner. Furthermore, in the light-receiving optical system with fewer pixels, the image processing load is reduced, thus improving the readout speed when capturing information codes readable in the light-receiving optical system with fewer pixels.

[0219] In addition, in multiple infrared light receiving optical systems, the shooting-related functions of one light receiving optical system that differ from the other light receiving optical system can be, as mentioned above, functions corresponding to the angle of view adjustment or functions corresponding to the number of pixels.

[0220] Furthermore, in multiple visible light receiving optical systems, a color sensor can be used as at least one receiving sensor to construct an information code (color code) that increases the storage capacity and allows for the reading of color information. Similarly, in multiple infrared light receiving optical systems, a color sensor can be used as at least one receiving sensor to construct a readable color code. Additionally, the features and structures of this embodiment and its variations can be applied to other embodiments.

[0221] Furthermore, the present invention is not limited to the embodiments described above, and may also be implemented as shown below, for example.

[0222] (1) In the reading process performed by the control unit 31, the image to be interpreted is not limited to the number of extractions of the position detection pattern or the number of black and white changes in a specific area. Alternatively, either the first image or the second image can be set as the interpretation object based on the result of the analysis processing of at least a portion of the first and second images. This reduces the processing load related to the interpretation process. In addition, in the reading process performed by the control unit 31, either the first image or the second image may not be set as the interpretation object. Instead, the image processing based on the information code of the first image and the interpretation processing based on the information code of the second image may be performed separately.

[0223] (2) The control unit 31 may also be configured to set the image of the object to be interpreted from the first image and the second image by means of an FPGA (Field Programmable Gate Array) set separately from the CPU, based on the number of extracted position detection graphics or the number of black and white changes in a specific area, and perform the interpretation processing of the information code of the image of the object to be interpreted by the CPU.

[0224] (3) The information code Ca that improves security by using the covering part Ca2 is not limited to being entirely covered by the covering part Ca2 in the code area Ca1, but can also be partially covered by the covering part Ca2 in the code area Ca1.

[0225] (4) The illumination light emitted by the second illumination units 21b-24b and 121b is not limited to infrared light; it can be any light in a specified second wavelength range that is different from the wavelength range of visible light. In this structure, the visible light cutoff filter 29 is configured to not transmit visible light but transmit the aforementioned specified second wavelength range of light. Alternatively, in the third embodiment described above, another filter configured to not transmit the aforementioned specified second wavelength range of light but transmit visible light can be used instead of the infrared light cutoff filter 29a.

[0226] (5) This invention is not limited to fixed information code reading devices, but can also be applied to portable information code reading devices.

[0227] Explanation of reference numerals in the attached figures

[0228] 1, 1a~1c, 100, 100a: Information code reading device

[0229] 3, 103: Shell

[0230] 5: Reading port

[0231] 21a~24a, 121a: First Illumination Section

[0232] 21b~24b, 121b: Second Illumination Section

[0233] 25a, 125a: First shooting unit

[0234] 25b, 125b: Second shooting unit

[0235] 27a, 127a: First imaging section (exposed section)

[0236] 27b, 127b: Second imaging section (exposed section)

[0237] 127c: Imaging section (exposed section)

[0238] 29, 129: Visible light cutoff filter (filter)

[0239] 29a: Infrared cutoff filter (other filters)

[0240] 31: Control Department (Processing Department, Lighting Control Department, Setting Department)

[0241] 31A: CPU

[0242] 60a~60e: Light-receiving optical system

[0243] 61a~61e: Light receiving sensor

[0244] 62a~62e: Imaging lenses

[0245] 150, 150a: Reflective components

[0246] 154, 154a, 154c: Opening

[0247] AR1a: Pre-reflection imaging range

[0248] AR1b: Shooting range after first reflection

[0249] AR2a: Second Reflection Front Imaging Range

[0250] AR2b: Shooting range after second reflection

[0251] Ca, Cb: Information codes

[0252] Ca1: Code area

[0253] Ca2: Coating layer

[0254] FPa, FPb: Position detection pattern (specific pattern)

[0255] Lfa: Visible light

[0256] Lfb: Infrared light (light in the specified second wavelength band)

[0257] S: Specific area

Claims

1. An information code reading device, characterized in that, have: case; The first lighting section can illuminate visible light; The second illumination unit can illuminate light of a predetermined second wavelength band that is different from the wavelength band of the visible light; The first imaging unit captures the information code scanned on the outer side of the reading surface of the housing under visible light irradiated by the first illumination unit. The second imaging unit captures the information code while the second illumination unit illuminates it with light of the second wavelength band. A filter is disposed within the imaging range of the second imaging unit, which does not transmit the visible light but transmits light of the second wavelength band; as well as The processing unit performs information code decoding based on at least one of the first captured image captured by the first imaging unit and the second captured image captured by the second imaging unit. as well as The housing contains a first illumination unit, a second illumination unit, a first imaging unit, a second imaging unit, a filter, and a processing unit, and a reading surface is provided on one side in the vertical direction. The first and second imaging units are arranged within the housing such that their imaging fields face the same direction, but their imaging ranges on the reading surface of the housing are different. Furthermore, when the information code scanned on the outside of the reading surface of the housing is imaged by the first and second imaging units, the distance from the information code to the first and second imaging units is set to be the same for both. The information code can be either an information code having a code area forming a specific pattern and at least a portion of the code area being covered by a coating portion that does not transmit the visible light but transmits light of the second wavelength band, or an information code whose code area is not covered by the coating portion.

2. The information code reading device according to claim 1, characterized in that, It includes a lighting control unit that controls the first lighting unit and the second lighting unit. The lighting control unit controls the first lighting unit to illuminate the visible light when the first imaging unit captures a picture, and controls the second lighting unit to illuminate the light of the second wavelength band when the second imaging unit captures a picture.

3. The information code reading device according to claim 1 or 2, characterized in that, The system includes a setting unit that, based on the result of parsing at least a portion of the first captured image and the second captured image, sets either the first captured image or the second captured image as the parsing object of the processing unit. The processing unit performs processing based on the captured image set by the setting unit as the object to be interpreted, interpreting the information code not covered by the overlay or the information code covered by the overlay.

4. The information code reading device according to claim 3, characterized in that, The information code is formed by configuring a predetermined number of position detection patterns, which are the specific patterns, within the code area. The setting unit performs the parsing process to extract the specific graphic from the first captured image and the second captured image respectively, and sets the captured image with the larger number of extracted specific graphics as the parsing object of the processing unit.

5. The information code reading device according to claim 3, characterized in that, The setting unit performs binarization on specific regions in both the first and second captured images as part of the parsing process, and performs a process to count the number of black-and-white changes along one or more scan lines within that specific region. The captured image with the higher number of changes is set as the object of interpretation by the processing unit.

6. The information code reading device according to claim 1 or 2, characterized in that, It is equipped with other filters, configured to correspond to the shooting range of the first imaging unit, which do not transmit light in the second wavelength band but transmit visible light.

7. The information code reading device according to claim 1 or 2, characterized in that, The first imaging unit has two or more light-receiving sensors, and is configured such that the light-receiving optical system of one side having a light-receiving sensor has different functions related to imaging than the light-receiving optical system of the other side having a light-receiving sensor.

8. The information code reading device according to claim 1 or 2, characterized in that, The second imaging unit has two or more light-receiving sensors, and the light-receiving optical system of one of the light-receiving sensors has different imaging-related functions from the light-receiving optical system of the other light-receiving sensor.

9. An information code reading device, characterized in that, have: case; The first lighting section can illuminate visible light; The second illumination unit can illuminate light of a predetermined second wavelength band that is different from the wavelength band of the visible light; The first imaging unit captures the information code scanned on the outer side of the reading surface of the housing under visible light irradiated by the first illumination unit. The second imaging unit captures the information code while the second illumination unit illuminates it with light of the second wavelength band. A filter is disposed in the imaging range of the second imaging unit, which does not transmit the visible light but transmits light of the second wavelength band; as well as The processing unit performs the process of deciphering the information code based on at least one of the first image captured by the first imaging unit and the second image captured by the second imaging unit; The housing contains a first illumination unit, a second illumination unit, a first imaging unit, a second imaging unit, a filter, and a processing unit, and a reading surface is provided on one side in the vertical direction. The first and second imaging units are configured such that the center of the field of view of the first imaging unit and the center of the field of view of the second imaging unit intersect at the center of the reading surface of the housing, and are capable of capturing the information code scanned on the outer side of the reading surface. When the information code is imaged by the first imaging unit and the second imaging unit, the distance from the information code to the first imaging unit and the second imaging unit is set to be the same for each other. The information code can be either an information code having a code area forming a specific pattern and at least a portion of the code area being covered by a coating portion that does not transmit the visible light but transmits light of the second wavelength band, or an information code whose code area is not covered by the coating portion.

10. An information code reading device, characterized in that, have: The first lighting section can illuminate visible light; The second illumination unit can illuminate light of a specified second wavelength band that is different from the wavelength band of visible light; The first imaging unit captures the information code while the visible light is illuminated by the first illumination unit; The second imaging unit captures the information code while the second illumination unit illuminates it with light of the second wavelength band. A filter is configured to correspond to the shooting range of the second imaging unit, which does not transmit visible light but transmits light in the second wavelength band; The processing unit performs the process of deciphering the information code based on at least one of the first image captured by the first imaging unit and the second image captured by the second imaging unit; The housing at least includes the first illumination unit, the second illumination unit, the first imaging unit, the second imaging unit, and the filter, and is provided with a reading surface for scanning the information code; and A reflective component, housed within the housing, reflects the visible light irradiated by the first illumination unit and the light of the second wavelength band irradiated by the second illumination unit toward the reading surface. When the area formed between the first imaging unit and the reading surface within the imaging range of the first imaging unit is defined as the first pre-reflection imaging range, and the area formed between the reading surface and the reflecting member in a manner connected to the first pre-reflection imaging range when the reading surface reflects to the inside of the housing is defined as the first post-reflection imaging range, and the area formed between the second imaging unit and the reading surface within the imaging range of the second imaging unit is defined as the second pre-reflection imaging range, and the area formed between the reading surface and the reflecting member in a manner connected to the second pre-reflection imaging range when the reading surface reflects to the inside of the housing is defined as the second post-reflection imaging range, then... The reflective component is positioned outside both the first and second pre-reflection imaging ranges. The first illumination unit, the second illumination unit, the first imaging unit, the second imaging unit, and the filter are positioned outside both the first and second reflection imaging ranges. The first illumination unit illuminates the visible light onto the first reflective surface of the reflective component, which serves as the first reflection imaging range. The second illumination unit irradiates the second wavelength band of light onto the second reflective surface of the reflective component, which is the second reflection imaging range.

11. The information code reading device according to claim 10, characterized in that, The first illumination unit illuminates the visible light in a manner that suppresses uneven illuminance distribution on the first reflective surface. The second illumination unit illuminates the second wavelength band of light in a manner that suppresses uneven illuminance distribution on the second reflective surface.

12. The information code reading device according to claim 10 or 11, characterized in that, The first illumination unit and the second illumination unit are surface light sources.

13. The information code reading device according to claim 12, characterized in that, The surface light source has the following features: The first light-emitting part and the second light-emitting part; and A light guide plate is disposed between the first light-emitting part and the second light-emitting part, and light from the first light-emitting part is incident on a first side, and light from the second light-emitting part is incident on a second side opposite to the first side. The light guide plate has multiple slots inside, which cause light incident from the first side and the second side to be reflected toward the exit surface. The asymmetric topography of the plurality of grooves is such that the shape of the face serving as the first side side is different from the shape of the face serving as the second side side.

14. The information code reading device according to claim 12, characterized in that, The surface light source includes a light-emitting part and a light guide plate, wherein light from the light-emitting part is incident on one side of the light guide plate. The light guide plate has multiple slots inside, which cause light incident from one side to be reflected toward the exit surface. When the side of the light guide plate opposite to one side is taken as another side, the plurality of grooves are asymmetrically formed so that the shape of the side that is one side is different from the shape of the side that is the other side.

15. The information code reading device according to claim 10, characterized in that, Louvers are provided on the illumination side of the first illumination unit and the second illumination unit, and the louvers are arranged with slats extending relative to a plane parallel to the reading surface.

16. The information code reading device according to claim 10, characterized in that, When viewed from the reading surface side, the opening provided in the reflective component has an exposed portion, and at least a portion of the edge forming the opening is configured to make the reflection state gradually brighter from the inside to the outside.

17. The information code reading device according to claim 16, characterized in that, The exposed portion is at least a part of the first camera portion and at least a part of the second camera portion.

18. The information code reading device according to claim 16, characterized in that, At least a portion of the edge forming the opening is covered by a coating component, the coating component being configured to make the reflective state gradually brighter from the inside to the outside.

19. The information code reading device according to claim 10, characterized in that, When viewed from the reading surface side, the opening provided in the reflective member exposes an exposed portion, which is formed such that when viewed from the reading surface side, the reflection state of the periphery, which is an outer ring-shaped edge, gradually brightens from the inside to the outside.

Images