TWI725329B - Two-dimensional code and two-dimensional code reading device - Google Patents

Abstract

In the three corners of the four corners of the rectangular code area (10), position detection patterns (11a-11c) for detecting the position of the code area (10) are respectively arranged. Moreover, each pattern part (21a-21d) of the specific pattern (21) is arrange|positioned along the outer side of the code area (10) and at least a part of the outer edge of this code area (10).

Description

Two-dimensional code and two-dimensional code reading device

The present invention relates to a two-dimensional code and a two-dimensional code reading device, in particular, to a two-dimensional code formed by arranging a plurality of grids in a matrix, and a two-dimensional code reading device for reading the two-dimensional code.

Previously, various two-dimensional codes were provided by arranging complex grids in a matrix. The reading device (two-dimensional code reader) that reads this type of two-dimensional code generally obtains the image data containing the two-dimensional code, and then specifies the area (code area) of the two-dimensional code from the image data. ) Analysis processing, and from the specified code area, the coordinate of each grid is determined based on the image content, the color of the grid is determined based on the image information at each coordinate position, and the constructor performs the decoding process. As a technique related to such a two-dimensional code, for example, a two-dimensional code disclosed in Patent Document 1 is known. [Prior Technical Document] [Patent Document]

[Patent Document 1] Japanese Patent No. 2938338 　　 [Patent Document 2] Japanese Patent Laid-Open No. 10-198754

[The problem to be solved by the invention]

When reading a two-dimensional code, it is necessary to specify the code area of the two-dimensional code and the coordinates of each grid occupied in the photographed image. If it is a QR code (registered trademark), the approximate position of the code area can be specified from the captured image by using the position detection patterns arranged in the three corners of the rectangular code area. On the other hand, in the case of a QR code, there is a corner where the position detection pattern does not exist in the code area. In order to correctly specify the code area, the position of the corner must be specified.

As a specific method of identifying the code area, there is, for example, the method disclosed in Patent Document 2. If a different color grid with a different color from the background color is arranged at the margin of the code area, various image processing methods can be used to specify the different color grid. By connecting the outer edges of the different-colored grid, the marginal part of the rectangular code area can be accurately extracted. As a method of arranging abnormal grids in the marginal part of the code region, in Patent Document 1, after arranging bright-colored grids (white grids) and dark-colored grids (black grids) in the data area, multiple types of grids are prepared by using In one of the mask patterns, a part of the grid is replaced, and the method of using the less continuous number of white grids and black grids as the optimal arrangement pattern. With this method, it is difficult for the light-colored grid (white grid) and the dark-colored grid (black grid) to be continuous in the portion adjacent to the background, and the background and the code region (rectangular region) can be distinguished well.

However, the types of mask patterns used are limited. Therefore, depending on the content of the stored data, there is a situation where light grids (white grids) and dark grids (black grids) are connected to the part adjacent to the background. When a grid of the same color as the background color is connected to a portion adjacent to the background, it becomes difficult to distinguish the code margin from the background, and the detection accuracy of the code area may be reduced. In addition, the pattern of the part adjacent to the background is different for each code. Therefore, when dirt is attached or the printing is blurred, it may be difficult to determine whether it is the correct grid color. As a result, the code area cannot be correctly specified. .

As another method, for example, like a data matrix, consider arranging a specific pattern formed by arranging dark grids followed by an L-shape on both sides of a rectangular code area, and arranging specific patterns formed by alternately arranging dark grids and bright grids on the other two sides. In this way, if the four sides of the rectangular code area are surrounded by the specific pattern, the background and the code area can be easily distinguished during reading, and the code area can be easily and accurately specified. However, most of the grids arranged in the code area need to be allocated to the grids of the aforementioned specific pattern. Therefore, the number of grids allocated to the data to be read has to be reduced, and there is a problem that the capacity of recordable data is reduced.

The present invention is the inventor in order to solve the above-mentioned problems, and its purpose is to provide a two-dimensional code that can accurately specify the code area without reducing the data capacity that can be recorded. [Means to solve the problem]

In order to achieve the foregoing purpose, the same invention is a two-dimensional code, which is a two-dimensional code (1, 1a~1g) arranged in a rectangular code area (10) in a lattice matrix, which is characterized by: 　　 as mentioned above The three corners of the four corners of the code area are respectively provided with position detection patterns (11a~11c) for detecting the position of the code area; 　　 is along the outer side of the aforementioned code area and at least a part of the outer edge of the code area The way to configure specific patterns (21~28).

In the invention of claim 1, the three corners of the four corners of the rectangular code area are respectively provided with position detection patterns for detecting the position of the code area, and are located along the outside of the code area and are A specific pattern is arranged in at least a part of the outer edge of the code area. In this way, in the captured image of the two-dimensional code, the specific pattern is captured along with the code area. Therefore, even when the two-dimensional code is captured obliquely and the state of dirt is attached, it can be based on The specific pattern and 3 position detection patterns can accurately specify the code area of the captured image. In particular, it is not necessary to assign a grid arranged in the code area to a specific pattern. Therefore, a two-dimensional code that can accurately specify the code area without reducing the recordable data capacity can be realized.

As an ideal example, the specific pattern is constituted so that the width is one division of a grid. Thereby, it is possible to suppress the increase in the area of the two-dimensional code caused by the setting of the specific pattern.

In addition, according to other ideal examples, a margin of a predetermined width is provided between the specific pattern and the outer edge of the code area. As a result, even a general reading device can easily recognize the specific pattern as a background different from the code area, so it can be read like a normal two-dimensional code. The specific pattern is set along the outer edge of the code area. The patterned two-dimensional code of the present invention.

Furthermore, according to other ideal examples, the margin of the predetermined width is formed in such a way that the width is 1 grid minute. Thereby, it is possible to suppress the increase in the area of the two-dimensional code caused by the provision of a specific pattern and a margin of a predetermined width.

Furthermore, according to an ideal example, the specific pattern is formed by arranging grids of the same color, so it is easy to identify the specific pattern itself in the photographed image.

Furthermore, according to an ideal example, the specific pattern is formed by arranging a plurality of grids in a way that the colors of adjacent grids are different. Therefore, when a specific pattern is recognized in the captured image, the coordinates of the grid constituting the specific pattern can be used to easily recognize the coordinates of each grid in the code area.

Furthermore, according to an ideal example, the specific pattern is provided with a pair of pattern portions facing each other across the code area; the pair of pattern portions are formed by arranging a plurality of grids in a row in a manner that the colors of adjacent grids are different. Therefore, when a specific pattern is recognized in the captured image, the coordinates of the grid constituting the specific pattern can be used to easily recognize the coordinates of each grid in the code area. In particular, the grids located in the code area on the line connecting one grid in the pattern portion on one side and one grid in the pattern portion on the other side of the pattern portion opposite to the one grid can be recognized as being arranged in the same Columns or grids of the same row. With this, for example, even in a situation where the code area is captured obliquely, the coordinates of each grid in the code area can be accurately recognized.

Furthermore, according to an ideal example, the specific pattern is provided with a first pattern portion and a second pattern portion that are orthogonal to each other along the two outer edges of the code area that constitute the remaining corners of the code area where the position detection pattern is not provided. . In this way, the position of the remaining corner can be specified based on the intersection of the first pattern portion and the second pattern portion. Therefore, even if the remaining corner has fewer dark grids and stains attached, the position can be accurately determined. Specific code area.

Furthermore, according to an ideal example, the specific pattern is formed into a four-corner ring by enclosing the code area, so the code area according to the specific pattern can be easily specified.

Furthermore, an ideal example is that a specific pattern is formed by arranging a plurality of grids in a row to enclose the code area to form a four-corner ring, and a part of the plurality of grids opposite to the position detection pattern is formed of grids of the same color. The grids in the lower part are formed in different colors from the adjacent grids. Thereby, the position of the pattern can be detected in a specific position based on the part of the specific pattern formed by grids of the same color. In addition, it is also possible to specify a part of a specific pattern formed by a grid of the same color based on the position of the position detection pattern. Furthermore, in the part of the specific pattern formed by the different-colored grids, the grids in the code area on the line connecting a pair of grids facing the code area can be recognized as grids arranged in the same row or row. . With this, for example, even in a situation where the code area is captured obliquely, the coordinates of each grid in the code area can be accurately recognized.

Furthermore, according to an ideal example, in the code area, the first fixed pattern that is different from the position detection pattern is composed and arranged by a plurality of grids; the specific pattern is formed by arranging the plurality of grids in a row to enclose the code area to form a four-corner ring The color of the grid projecting the center of the first fixed pattern is different from that of the adjacent grid. Thereby, even in the imaging state where it is difficult to recognize the first fixed pattern, the position of the first fixed pattern can be specified based on the specific pattern. In addition, the position of the specific pattern may be specified based on the position of the first fixed pattern.

Furthermore, according to an ideal example, in the code area, the second fixed pattern, which is different from the position detection pattern, is composed of a predetermined arrangement of plural grids and arranged; the specific pattern is formed by arranging the plural grids in a row to enclose the code area. It has a four-corner ring shape, and is configured such that a plurality of grids projecting the position of the second fixed pattern are arranged in a predetermined arrangement. Thereby, even in an imaging state where it is difficult to recognize the second fixed pattern, the position and arrangement of the second fixed pattern can be specified based on the specific pattern. In addition, the position of the specific pattern may be specified based on the position of the second fixed pattern.

In addition, another aspect of the invention provides a two-dimensional code reading device (30), which optically reads a two-dimensional code (1, 1a~1g) arranged in a rectangular code area (10) in a lattice matrix. , Characterized in that: the device is equipped with: 　　 camera means (33), which can photograph the aforementioned two-dimensional code; 　　 specific means (40), which specifies the position of the aforementioned code area of the image taken by the aforementioned camera means; and an interpretation means (40), interpret the two-dimensional code based on the code area specified by the specific means; 　　 the two-dimensional code is located in the three corners of the four corners of the code area, and is set to detect the code area. The position detection pattern (11a-11c) of the position, and the specific pattern (21-28) is arranged along the outer side of the aforementioned code area and is at least a part of the outer edge of the code area; 　　The aforementioned specific means is based on the aforementioned The position detection pattern and the aforementioned specific pattern specify the position of the aforementioned code area of the aforementioned captured image.

In the two-dimensional code reading device (30), the three corners of the rectangular code area are respectively provided with position detection patterns for detecting the position of the code area, and are located along the outer side of the code area and are The two-dimensional code with a specific pattern is arranged in at least a part of the outer edge of the code area, and becomes the reading target of the two-dimensional code reading device. In this way, in the captured image of the aforementioned two-dimensional code, the specific pattern and its code area are captured together. Therefore, the code area of the captured image can be accurately specified by a specific method based on the specific pattern and 3 position detection patterns. . In particular, it is not necessary to assign a grid arranged in the code area to a specific pattern. Therefore, a two-dimensional code that can accurately specify the code area without reducing the recordable data capacity can be realized.

In addition, the symbols in the aforementioned parentheses indicate the correspondence with the specific means described in the embodiments described later.

[First Embodiment] 　　 Hereinafter, the first embodiment of a two-dimensional code and a two-dimensional code reading device that specifically implements the present invention will be described with reference to the drawings.

First, referring to FIG. 1, the structure of the two-dimensional code (two-dimensional information code) of this embodiment will be described.

As shown in FIG. 1, the two-dimensional code 1 of the present embodiment has a rectangular (more specifically, a square shape) code area 10 having a horizontal direction (X direction) and a vertical direction (Y direction). On the inner side of the code area 10, plural information display unit grids (hereinafter, also simply referred to as grids) are arranged in a matrix to extend along the outer side of the code area 10 and at least a part of the outer edge of the code area 10 The pattern is configured by a specific pattern 21. Each grid is a plurality of types of grids different in color, density, or brightness, and each grid area is configured as a square area.

The code area 10 has four corners 10a~10c and 12, but the three corners 10a~10c are respectively provided with position detection patterns (Finder patterns) 11a~11c for detecting the position of the code area 10, and the remaining corners 12 No position detection pattern is set. Therefore, by these four corners 10a-10c and 12, the code area 10 is defined from the background BK. In the code area 10, a data recording area DR for recording desired data by a plurality of grids is arranged. The corner 12 that is not provided with the above-mentioned position detection pattern is also configured to be used as a part of the data recording area DR. Also, in the code area 10, although not described in detail, an error correction symbol recording area EC in which error correction symbols are recorded by a plurality of grids is provided. Furthermore, in the present embodiment, the code area 10 is constructed using the same technique as the well-known QR code. In FIG. 1, for the convenience of explanation, except for the position detection patterns 11a-11c, each is shown in bright-colored grids (white grids). lattice.

The specific pattern 21 is shown in FIG. 1, and has three position detection patterns 11a-11c and one corner 12. In the horizontal direction (X direction) and the vertical direction (Y direction), the two patterns facing each other or the pattern and Yu's combination. Therefore, the specific pattern 21 is provided with a pattern portion 21a arranged to connect two position detection patterns 11a and 11b facing each other in the horizontal direction, and two position detection patterns facing each other in the vertical direction. The pattern portion 21b arranged in the manner of the pattern 11a and the position detection pattern 11c, the pattern portion 21c arranged in such a manner that the position detection patterns 11c and the corner 12 facing each other in the horizontal direction are connected to each other, and the pattern portion 21c is arranged to be connected to each other in the vertical direction. The pattern portion 21d arranged in the manner of the pattern 11b and the corner 12 is detected in the direction of the position. The pattern parts 21a-21d are arranged in such a way that they are connected to the outer edge of the code area 10 without gaps, and the plural grids are arranged in a row in such a way that the colors of adjacent grids are different, and the width becomes one grid division. Way of composition. Specifically, each of the pattern portions 21a-21d is configured in such a manner that bright-colored grids (white grids) and dark-colored grids (black grids) are alternately arranged in a row along the outer edge of the code region 10.

The specific pattern 21 is configured as described above. Therefore, in the information code reading device 30, not only the three position detection patterns 11a to 11c but also the specific pattern 21 can be used to accurately specify the code area 10 from the captured image.

Next, the information code reading device 30 having a function as a two-dimensional information code reading device capable of optically reading the two-dimensional code 1 of this embodiment will be described with reference to FIG. 2.

The information code reading device 30 of this embodiment is a reading device that optically reads the two-dimensional code 1 and barcodes. As shown in FIG. 2, the information code reading device 30 is formed by accommodating a circuit part inside a casing not shown. The circuit part mainly includes an optical system such as an illuminating light source 31, a light receiving sensor 33, an imaging lens 32, etc. , And a microcomputer (hereinafter referred to as "microcomputer") such as the memory 36 and the control unit 40.

The optical system is divided into a light-projecting optical system and a light-receiving optical system. The illumination light source 31 constituting the projection optical system has a function of an illumination light source capable of emitting the illumination light Lf, and is composed of, for example, a red LED and a lens provided on the emission side of the LED. Furthermore, in FIG. 2, an example in which the illumination light Lf is irradiated toward the reading target R with the two-dimensional code 1 is conceptually disclosed.

The light-receiving optical system is composed of a light-receiving sensor 33, an imaging lens 32, a mirror (not shown), and the like. The light-receiving sensor 33 is, for example, a solid-state imaging device such as a C-MOS or CCD, that is, an area sensor in which light-receiving elements are two-dimensionally arranged, and output corresponding reflected light Lr in each grid (pattern) corresponding to the received information code The intensity of the electrical signal is constituted by the way. The light-receiving sensor 33 is mounted on a printed wiring board (not shown in the figure) so as to be able to receive incident light incident through the imaging lens 32. Furthermore, the light-receiving sensor 33 may be equivalent to an example of the “imaging means” capable of imaging the two-dimensional code 1.

The imaging lens 32 has a function as an imaging optical system that collects incident light from the outside through a reading port (not shown) and can form an image on the light-receiving surface 33a of the light-receiving sensor 33. In this embodiment, after the information code is reflected by the illumination light Lf etc. irradiated from the illumination light source 31, the reflected light Lr is condensed by the imaging lens 32 to form the code image on the light receiving surface 33a of the light receiving sensor 33.

The microcomputer system consists of an amplifier circuit 34, an A/D conversion circuit 35, a memory 36, an address generation circuit 37, a synchronization signal generation circuit 38, a control unit 40, an operation unit 42, a liquid crystal display 43, a buzzer 44, and a vibrator 45. The light emitting unit 46, the communication interface 48 and the like are constituted. The microcomputer is, as its name suggests, it is composed of a control unit 40 and a memory 36 that can function as a microcomputer (information processing device), and can be configured to include a two-dimensional code captured by the above-mentioned optical system. The image signal of the information code, hardware and software for signal processing. In addition, the control unit 40 also performs control related to the entire system of the information code reading device 30.

The image signal (analog signal) output from the light-receiving sensor 33 of the optical system is input to the amplifying circuit 34 and amplified with a predetermined gain, and when it is input to the A/D conversion circuit 35, it is converted from an analog signal to a digital signal. Then, when the digitized image signal, that is, the image data (image information) is input to the memory 36, it is accumulated in the image data accumulation area. Furthermore, the synchronization signal generating circuit 38 is configured to generate a synchronization signal to the light-receiving sensor 33 and the address generating circuit 37, and the address generating circuit 37 is configured to be capable of being supplied from the synchronization signal generating circuit 38 The synchronization signal generates the storage address of the image data stored in the memory 36.

The memory 36 is a semiconductor memory device, for example, RAM (DRAM, SRAM, etc.) or ROM (EPROM, EEPROM, etc.) corresponds to it. The RAM in the memory 36 is configured such that in addition to the above-mentioned image data accumulation area, the control unit 40 can also secure a work area and a reading condition table for each processing such as arithmetic operation and logical operation. In addition, in the ROM, a system program that can control each hardware of the illumination light source 31, the light receiving sensor 33, and the like is stored in advance. In addition, the memory 36 also stores information related to a specific pattern of the two-dimensional code to be read, a reading program that can be used for the reading process described later, and the like. Here, the information related to the specific pattern of the two-dimensional code includes, for example, the shape of the specific pattern that also includes the color of the grid of the structure and the relative positional relationship with each of the position detection patterns 11a to 11c.

The control unit 40 is a microcomputer that can control the entire information code reading device 30. It is composed of a CPU, a system bus, an I/O interface, etc., and can form an information processing device together with the memory 36 and has an information processing function. The control unit 40 is configured to be connected to various input/output devices (peripheral devices) through a built-in input/output interface. In the case of this embodiment, the operation unit 42, the liquid crystal display 43, the buzzer 44, and the vibration are connected. The device 45, the light emitting unit 46, the communication interface 48 and so on.

The operation unit 42 is composed of a plurality of keys, and is a structure for giving operation signals to the control unit 40 in response to the user's key operations. When the control unit 40 receives the operation signals from the operation unit 42, it performs actions in response to the operation signals. The way to constitute. The liquid crystal display 43 is composed of a well-known liquid crystal display panel, and the display content is controlled by the control unit 40. The buzzer 44 is composed of a known buzzer, and is configured to generate a predetermined sound in response to an operation signal from the control unit 40. The vibrator 45 is composed of a well-known vibrator mounted on a portable device, and is configured to generate vibration in response to a driving signal from the control unit 40. The light emitting unit 46 is, for example, an LED, and is configured to light up in response to a signal from the control unit 40. The communication interface 48 is configured as an interface for data communication with the outside (for example, a host device), as a structure for performing communication processing in cooperation with the control unit 40.

Next, the reading process executed by the control unit 40 of the information code reading device 30 when reading the two-dimensional code 1 will be described with reference to the flowchart of FIG. 3.

When a predetermined operation is performed on the operation unit 42 with the reading port of the information code reading device 30 facing the two-dimensional code 1, the reading process by the control unit 40 is started. First, the imaging process shown in step S101 is performed to generate image data including the captured image of the two-dimensional code 1 based on the signal output from the light-receiving sensor 33 that receives the reflected light Lr from the two-dimensional code 1.

Next, the specific pattern extraction process shown in step S103 is performed. In this process, a process of extracting the specific pattern 21 from the captured image captured as described above is performed based on information about the specific pattern 21 stored in the memory 36 in advance, and the like. In this process, the specific pattern 21 may be directly extracted from the captured image. Since the positional relationship between the specific pattern 21 and each position detection pattern 11a-11c is determined in advance, it is based on the position detection patterns 11a-11c detected from the captured image. The position may be estimated from the same captured image and the specific pattern 21 may be extracted.

Then, since the two-dimensional code 1 with the specific pattern 21 is captured, when the specific pattern 21 is extracted and recognized from the captured image (Yes in step S105), the code area identification using the specific pattern shown in step S107 is performed deal with. In this processing, processing for identifying the code area 10 based on the position detection patterns 11a to 11c extracted from the same captured image and the specific pattern 21 extracted as described above is performed. Specifically, the four intersections at which the lines extending from the inner edges of the respective pattern portions 21a-21d of the extracted specific pattern 21 intersect correspond to the corners of the four corners 10a-10c and 12 of the code area 10. Therefore, according to each pattern portion 21a ~21d, specify the remaining corner 12 and confirm that the vertex angles of the three corners 10a to 10c other than the remaining corner 12 coincide with the corresponding vertex angles of the position detection patterns 11a to 11c. In addition, the control unit 40 that performs the processing of the aforementioned step S107 may correspond to an example of the "specified means".

On the other hand, when the specific pattern 21 is not extracted from the captured image (step S105: No), the normal code area identification process shown in step S109 is performed, and the normal information code without the specific pattern 21 is performed In imaging, a process for identifying the code area 10 is performed by detecting a pattern from the captured image based on a position, and the like.

In the processing of step S107 or step S109, if the position detection patterns 11a to 11c, etc. are not extracted and the identification of the code area 10 fails (No in step S111), the processing from step S101 is performed.

On the other hand, in the processing of step S105 or step S107, when the identification of the code area 10 is successful (Yes in step S111), the decoding processing shown in step S113 is performed. In this processing, processing for decoding (deciphering) the predetermined data recorded in the data recording area is performed based on the arrangement of the respective grids in the code area 10 specified as described above. Then, when the decoding process is successful (Yes in step S115), a process for outputting the predetermined data obtained by the decoding process to the outside is performed (step S117), and the reading process is ended. On the other hand, when the decoding process fails (No in step S115), the process from step S101 is performed. Furthermore, the control unit 40 that performs the processing of the aforementioned step S113 may correspond to an example of the "interpretation means".

As described above, in the two-dimensional code 1 of this embodiment, the three corners 10a to 10c of the rectangular code area 10 are respectively provided with position detection patterns 11a to 11c for detecting the position of the code area 10, and The pattern portions 21 a to 21 d of the specific pattern 21 are arranged along the outer side of the code area 10 and are at least a part of the outer edge of the code area 10. In this way, in the captured image of the two-dimensional code 1, the specific pattern 21 is captured together with the code area 10. Therefore, even in the situation where the two-dimensional code 1 is captured obliquely or when dirt is attached, etc. , The code area 10 of the captured image can also be correctly specified based on the specific pattern 21 and the three position detection patterns 11a-11c. In particular, it is not necessary to assign the grids arranged in the code area 10 to the specific pattern 21, and therefore, it is possible to realize the two-dimensional code 1 that can accurately specify the code area 10 without reducing the recordable data capacity.

Then, in the information code reading device 30 of the present embodiment, in the captured image of the two-dimensional code 1, the specific pattern 21 is captured together with the code area 10. Therefore, in the reading process performed by the control unit 40 According to the specific pattern 21 and the three position detection patterns 11a~11c, the code area 10 of the captured image can be correctly specified.

Furthermore, each pattern part 21a-21d of the specific pattern 21 is comprised so that the width may become 1 division of a grid. Thereby, it is possible to suppress an increase in the area of the two-dimensional code 1 due to the provision of the specific pattern 21 and the respective pattern portions 21a to 21d.

In particular, in this embodiment, the pattern portion 21a and the pattern portion 21c function as a pair of pattern portions via the code area 10, and the pattern portion 21b and the pattern portion 21d have functions as a pair of pattern portions via the code area 10. Features. Then, each pattern portion 21a-21d is configured by arranging a plurality of grids in a row such that the colors of adjacent grids are different. Therefore, when the pattern portions 21a to 21d of the specific pattern 21 are recognized in the captured image, the coordinates of the grids constituting the pattern portions 21a to 21d can be used to easily recognize the coordinates of the grids in the code area 10.

That is, the edge part 101a and edge part 101b of the code area are constructed in such a way that the colors of adjacent grids are different, and the edge part 101c and the edge part 101d of the code area are constructed in such a way that the colors of adjacent grids are the same. In the matrix 100, as illustrated in FIG. 6, when the code area is imaged with an elevation angle and a skew like an inclination angle, there is a situation in which the positions of the grids in the code area cannot be accurately obtained from the respective edge portions 101a to 101d. Specifically, for example, as illustrated in FIG. 6, when the y coordinate of each grid in the nth row from the top of the code area is obtained, the grid coordinates (point Ao, etc.) on the side of the edge 101b can be based on the The coordinates of the grid are determined, but the grid coordinates on the side of the edge 101d (point Bo, etc.) are difficult to obtain accurately because the margin between the grids of the edge 101d cannot be distinguished. In this situation, the method of dividing the edge 101d into n:m positions based on the number of grids is also considered to obtain the grid coordinates on the side of the edge 101d (point Bo, etc.). However, it is due to the elevation angle and the inclination angle. There is a situation where the position of the division into n:m becomes incorrect, such as mesa skew and lens distortion (Distortion), and the grid coordinates cannot be accurately obtained. Similarly, even in a situation where the x coordinates (position coordinates in the lateral direction X) of each grid are obtained, the grid coordinates on the side of the edge 101a can be determined based on the coordinates of the grid on the edge 101a, but the edge 101c The grid coordinates on the side are difficult to obtain accurately because the margin between the grids of the edge 101c cannot be distinguished.

On the other hand, as in the present invention, the pattern parts 21a to 21d are configured in such a way that the colors of adjacent grids are different, and the aforementioned problem can be solved. That is, the grids located in the code area on the line connecting one grid in the pattern portion on one side and one grid in the pattern portion on the other side of the pattern portion opposite to the one grid can be recognized as being arranged in Grids in the same column or row. As a result, as illustrated in FIG. 4, even if the code area 10 is taken skewedly, the y coordinate (position coordinate in the vertical direction Y) of each grid in the nth row from the top of the code area 10 is obtained. The grid coordinates (point A, etc.) on the side of the portion 21b can also be determined based on the coordinates of the grid corresponding to the nth row of the pattern portion 21b, and the grid coordinates (point B, etc.) on the side of the pattern portion 21d can also be determined based on the grid coordinates (point B, etc.) corresponding to the pattern. The coordinates of the grid in the nth row of the part 21d are determined. Similarly, the grid coordinates on the side of the pattern portion 21a can be determined based on the coordinates of the grid on the pattern portion 21a, and the grid coordinates on the side of the pattern portion 21c can be determined based on the coordinates of the grid on the pattern portion 21c. Therefore, the coordinates of each grid in the code area 10 can be accurately recognized based on the respective pattern portions 21a-21d.

Furthermore, even if a part of the code area 10 is not captured, the coordinates of the grids in the specific pattern 21 can be used to correctly recognize the coordinates of the grids in the code area 10 of the captured portion and then perform error correction. For example, as illustrated in FIG. 5, even if a part of the code area 10 is not captured, the code of the captured part can be accurately recognized by using the coordinates of the grid of the pattern part 21b and the coordinates of the grid of the pattern part 21d. The coordinates of each grid in area 10 are then corrected for errors.

As a result, compared with the situation where the specific pattern 21 is not provided, the error correction based on the misrecognized coordinates can be suppressed. Therefore, even in a situation where a part of the code area 10 is missing, etc., the possibility of correct error correction can be improved. It can improve the decoding success rate. In addition, in situations where the image is captured without skew and where the image is captured with less skew, one of the grids in one of the pattern parts and the other pattern part located opposite to the one grid are not used. The line of the grid may determine the coordinates of the grid located in the code area 10 near the grid based on the coordinates of the grid of the pattern part.

In addition, in this embodiment, the specific pattern 21 has points Do not follow the two outer edges of the code area 10 along the remaining corners 12 of the code area 10 where the position detection patterns 11a-11c are not provided, and the two outer edges of the code area 10 are orthogonal to each other as the first pattern portion and the second pattern portion. 21c and pattern part 21d. Thereby, the position of the aforementioned remaining corner 12 can be specified according to the intersection of the line extending from the inner edge of the pattern portion 21c and the line extending from the inner edge of the pattern portion 21d. Therefore, even if the dark grid of the remaining corner 12 is relatively The code area 10 can be accurately specified even in a few situations and in situations where dirt is attached.

Furthermore, as the specific patterns of the first pattern portion and the second pattern portion that specify the positions of the remaining corners 12, it is not limited to the above-mentioned specific patterns 21, and the respective patterns along the remaining corners 12 are used. The two outer edges of the code area 10 may have a first pattern portion and a second pattern portion that are orthogonal to each other. Specifically, as a first modification of this embodiment, for example, the specific pattern 22 of the two-dimensional code 1a illustrated in FIG. Edge, and the first pattern portion 22a and the second pattern portion 22b orthogonal to each other. Even so, for example, as illustrated in FIG. 8, even in a situation where dirt and the like D adhere to the remaining corner 12, the intersection of the line L1 extended by the inner edge of the pattern portion 22a and the line L2 extended by the inner edge of the pattern portion 22b , Specify the position of the aforementioned remaining corner 12, and the code area 10 can be accurately specified.

As a second modification of this embodiment, a margin of a predetermined width may be provided between the specific pattern and the outer edge of the code area. Here, the predetermined width refers to the distance between the outer edge of the code area in the horizontal direction (X direction) and the specific pattern, and the distance between the outer edge of the code area in the vertical direction (Y direction) and the specific pattern. Specifically, the two-dimensional code 1b as illustrated in FIG. 9 is provided between each pattern portion 23a to 23d of the specific pattern 23 and the outer edge of the code area 10. Use the same color as the bright color grid to set a margin M whose width becomes a predetermined width of 1 grid.

In the two-dimensional code, there is a blank area with a certain width around the code area required by the specification. In the structure of the two-dimensional code 1 shown in FIG. 1, the pattern portions 21a-21d of the specific pattern 21 are arranged to be connected to the outer edge of the code area 10 without gaps. Therefore, in a general reading device, There may be cases where it cannot be read because of the specific pattern 21.

Therefore, the two-dimensional code 1b illustrated in FIG. 9 uses a margin M of a predetermined width between each pattern portion 23a-23d and the outer edge of the code area 10. Even a general reading device can easily identify The pattern 23 is recognized as a background different from the code area 10 and the like. Therefore, the two-dimensional code 1b with the specific pattern 23 arranged along the outer edge of the code area 10 can be read like a normal two-dimensional code.

In particular, the margin M of the predetermined width is configured such that the width becomes 1 grid part, so it is possible to suppress the increase in the area of the two-dimensional code 1b due to the provision of the specific pattern 23 and the margin M of the predetermined width. In addition, the width of the margin M of the predetermined width may be changed in accordance with the width of the blank area required by the specifications.

[Second Embodiment]

Next, the two-dimensional code of the second embodiment will be described with reference to FIG. 10.

In the second embodiment, the specific pattern is mainly formed in a quadrangular ring to surround the code area 10, which is similar to the first embodiment described above. State is different. Specifically, the specific pattern 24 of the two-dimensional code 1c shown in FIG. 10 uses a plurality of grids to be arranged in a row by enclosing the code area 10 with a margin M of a predetermined width, and the colors of adjacent grids are different. The way is arranged to form a four-corner ring.

In this way, the specific pattern 24 is formed into a four-corner ring to surround the code area 10, so the code area 10 based on the specific pattern 24 can be easily specified. In particular, the specific patterns 24 are arranged in such a way that the colors of adjacent grids are different. Therefore, as explained using FIG. 4, the coordinates of the grids constituting the specific pattern 24 can be used to easily identify the coordinates of the grids in the code area 10. .

As a first modification of the second embodiment, the specific pattern 25 of the two-dimensional code 1d shown in FIG. 11 is arranged in a row with grids of the same color to surround the code area 10 with a margin M of a predetermined width. It is also possible to form a quadrangular ring. Even so, the code area 10 can be easily specified based on the specific pattern 25 formed in a quadrangular ring to surround the code area 10. In particular, the specific pattern 25 is formed by arranging grids of the same color, so the specific pattern 25 itself can be easily recognized in the captured image.

As a second modification of the second embodiment, the specific pattern 26 of the two-dimensional code 1e shown in FIG. The grid structure of the same color may be configured with the pattern portion 26b formed by the remaining grids in a color different from the grids on the side. Thereby, the positions of the patterns 11a to 11c can be detected based on the pattern portion 26a formed of the same color grid. In addition, the pattern portion 26a may be specified based on the positions of the position detection patterns 11a to 11c. Furthermore, in the pattern portion 26b composed of a grid of different colors, the grids in the code area 10 on the line connecting a pair of grids facing the code area 10 can be recognized as being arranged in the same column or row lattice. Thereby, for example, even in a situation where the code area 10 is captured obliquely, the coordinates of each grid in the code area 10 can be accurately recognized.

[Third embodiment] 　　 Next, the two-dimensional code of the third embodiment will be described with reference to FIG. 13.

In this third embodiment, the arrangement of the grids constituting the specific pattern is mainly changed in accordance with the shape of the fixed pattern arranged in the code area 10, which is different from the aforementioned second embodiment. Specifically, in the two-dimensional code 1f shown in FIG. 13, in the code area 10, as the first fixed pattern different from the position detection patterns 11a to 11c, six calibration patterns 13a to 13f are arranged so as to space a predetermined A four-corner ring-shaped specific pattern 27 is arranged in such a way that the margin M of the width surrounds the code area 10. Each of the calibration patterns 13a to 13f has the same function as the calibration pattern of the QR code (registered trademark), and uses the calibration pattern to correct the skew of the grid in the enclosed area. The calibration patterns 13a~13f have the same shape, and in the x coordinate, the calibration patterns 13a, 13c, 13e are the same, the calibration patterns 13d, 13f are the same, in the y coordinate, the calibration patterns 13b~13d are the same, and the calibration patterns 13e, 13e, Configure separately in the same way as 13f.

The specific pattern 27 of this embodiment is formed by arranging a plurality of grids in a row to enclose the code area 10 to form a four-corner ring, and projecting the grid at the center of each calibration pattern 13a to 13f and the adjacent grid The colors are composed in different ways. Specifically, in the pattern portion 27a and the pattern portion 27c of the specific pattern 27, the positions of the grids forming the center positions of the calibration patterns 13b and the positions of the grids constituting the center positions of the calibration patterns 13a, 13c, and 13e are projected The grids and the grids projecting the positions of the grids that constitute the center positions of the calibration patterns 13d and 13f are formed as bright-colored grids, and the rest are formed as dark-colored grids. In addition, in the pattern portion 27b and the pattern portion 27d of the specific pattern 27, the grids projecting the positions of the grids constituting the center position of the calibration pattern 13a, the grids projecting the positions of the grids constituting the center position of the calibration patterns 13b to 13d, and the projection The grids constituting the positions of the grids at the center positions of the calibration patterns 13e and 13f are formed as bright-colored grids, and the rest are formed as dark-colored grids.

Thereby, even if it is difficult to recognize the imaging state of any one of the calibration patterns 13a to 13f, for example, the position of the calibration pattern can be specified based on the specific pattern 27. In addition, it is also possible to specify the position of a specific pattern by detecting a bright-colored grid that is the position of a grid that forms the center position of each calibration pattern 13a to 13f, and the dark grids adjacent to it. Furthermore, the bright-colored grid system of the specific pattern 27 can function like a calibration pattern, so for example, the distortion of the grid in the area surrounded by the two bright-colored grids of the specific pattern 27 and the calibration patterns 13a to 13f can be corrected. That is, by using the bright-colored grid portion of the specific pattern 27, the skew of the grid arranged on the outside can also be corrected by the calibration patterns 13a to 13f in the code area 10.

[Fourth Embodiment]

Next, the two-dimensional code of the fourth embodiment will be described with reference to FIG. 14.

In the fourth embodiment, when the second fixed pattern which is different from the calibration pattern arranged in the code area 10 is configured in a predetermined arrangement, the plural grids at the position where the second fixed pattern is projected become the predetermined arrangement. The way in which the specific pattern is formed is different from the third embodiment described above.

Specifically, for example, as shown in the two-dimensional code 1g shown in FIG. 14, in the code area 10 as the second fixed pattern, when two timing patterns 14a, 14b are arranged in a predetermined arrangement, the specific pattern 28 is projected from the timing pattern 14a The pattern portion 28a formed by the plurality of grids at the position of 14b is configured such that the pattern portion 28b formed by the plurality of grids at the position of the projection timing pattern 14b is arranged in the aforementioned predetermined arrangement.

Thereby, even if it is difficult to recognize the imaging state of the timing patterns 14a, 14b in the code area 10, the positions and arrangements of the timing patterns 14a, 14b can be specified based on the pattern portions 28a, 28b of the specific pattern 28. In addition, the positions of the pattern portions 28a and 28b of the specific pattern 28 may be specified by detecting the grids of the same arrangement on the target of the projection timing patterns 14a and 14b. In particular, by using both the timing patterns 14a and 14b in the code area 10 and the pattern portions 28a and 28b outside the code area 10, as illustrated in FIG. 4, even if the two-dimensional code 1g is captured skewedly, The coordinates of each grid in the code area 10 can be correctly identified.

Furthermore, even in a situation where a part of the two-dimensional code 1g is lackingly captured as illustrated in FIG. 15, it is possible to use the frame of the pattern part 28b. The coordinates of the sub-coordinates and the grid coordinates of the timing pattern 14b are as described with reference to FIG. 5, and the coordinates of each grid in the code area 10 of the imaged part are correctly identified and then the error is corrected. As a result, compared with the situation where the specific pattern 28 is not provided, the error correction based on the misrecognized coordinates can be suppressed, so even in the situation where a part of the code area 10 is missing, etc., the possibility of correcting the error can be improved. It can improve the decoding success rate.

In addition, the present invention is not limited to the aforementioned embodiments and modifications, and may be embodied as described below, for example.

(1) The specific pattern of the present invention is not limited to the above-mentioned specific patterns 21-28. For example, solid lines and other shapes other than grids are used to extend along the outer side of the code area 10, and the code area 10 The arrangement of at least a part of the outer edge of the code area may be configured in a shape that can specify the position of the code area 10. In addition, when grids of the same color are arranged to form a specific pattern in a predetermined shape, the specific pattern itself can be easily recognized in the captured image. In addition, when a plurality of grids are arranged in such a way that the colors of adjacent grids are different, and a specific pattern is formed in a predetermined shape, the coordinates of the grids constituting the specific pattern can be used to easily identify the coordinates of each grid in the code area 10.

(2) The code area 10 and the specific patterns 21 to 28 are not limited to being composed of bright-colored grids (white grids) and dark-colored grids (black grids), but may be composed of grids of plural kinds of colors. In addition, the code area 10 is not limited to being formed in a square shape, and may be formed in a rectangular shape.

(3) Even if the two-dimensional codes 1 and 1a to 1g configured as described above are displayed on a predetermined display medium such as paper, they can be read by the information code reading device 30 to achieve the aforementioned effects. At this time, the two-dimensional codes 1, 1a~1g are not limited to be displayed in such a way that one of the three position detection patterns 11a~11c (11c) becomes the bottom for a given display medium, such as the display medium shown in Figure 16. Generally, it is acceptable to display two of the three position detection patterns 11a to 11c (11a, 11b) as the bottom. On the remaining corner 12 side of the code area 10 where the position detection patterns 11a~11c are not set, the data recording area for recording the data to be read is arranged, and the two position detection patterns are arranged below, and the data recording area is Become the top configuration. The data recording area is arranged such that the data recording area becomes the upper side and displayed on a fixed object. Even if the lower part of the code area constituting the two-dimensional code is hidden because the moving object before moving to the fixed object, etc., the data recording area is still hidden. It is difficult to be hidden. Compared with the situation where two of the three position detection patterns are placed on the top, the reading success rate of the data recorded in the two-dimensional code can be improved.

(4) The two-dimensional code reading device of the present invention is not limited to being applied to the information code reading device 30 configured as described above, for example, it is installed to read a predetermined application of two-dimensional codes 1, 1a~1g, etc. It can also be used as a portable terminal such as a mobile phone or a smart phone of a program, and it can also be used as a stationary information terminal.

1‧‧‧Two-dimensional code (two-dimensional information code) 1a‧‧‧ two-dimensional code (two-dimensional information code) 1b‧‧‧ two-dimensional code (two-dimensional information code) 1c‧‧‧ two-dimensional code (two-dimensional information Code) 1d‧‧‧Two-dimensional code (two-dimensional information code) 1e‧‧‧Two-dimensional code (two-dimensional information code) 1f‧‧‧Two-dimensional code (two-dimensional information code) 1g‧‧‧Two-dimensional code (two (Dimensional information code) 10‧‧‧Code area 10a‧‧‧Mitsuyu 10b‧‧‧Mitsuyu 10c‧‧‧Sanyu11a‧‧‧Position detection pattern 11b‧‧‧Position detection pattern 11c‧‧‧Position detection pattern 12‧‧‧ Remaining corner 13a‧‧‧calibration pattern (1st fixed pattern) 13b‧‧‧calibration pattern (1st fixed pattern) 13c‧‧‧calibration pattern (1st fixed pattern) 13d‧‧‧calibration pattern (1st fixed pattern) Pattern) 13e‧‧‧Calibration pattern (1st fixed pattern) 13f‧‧‧Calibration pattern (1st fixed pattern) 14a‧‧‧ Timing pattern (2nd fixed pattern) 14b‧‧‧ Timing pattern (2nd fixed pattern) 21‧‧‧Specified pattern 21a‧‧‧Pattern part 21b‧‧‧Pattern part 21c‧‧‧Pattern part 21d‧‧‧Pattern part 22‧‧‧Specific pattern 23‧‧‧Specific pattern 24‧‧‧Specific pattern 25‧ ‧‧Specific pattern 26‧‧‧Specific pattern 27‧‧‧Specific pattern 28‧‧‧Specific pattern 30‧‧‧Information code reading device (two-dimensional information code reading device) 31‧‧‧Illumination light source 32‧‧‧ Imaging lens 33‧‧‧Receiving sensor (camera means) 33a‧‧‧Receiving surface 34‧‧‧Amplifying circuit 35‧‧‧A/D conversion circuit 36‧‧‧Memory 37‧‧‧Address generating circuit 38 ‧‧‧Synchronization signal generating circuit 40‧‧‧Control part (specific means, interpretation means) 42‧‧‧Operation part 43‧‧‧LCD display 44‧‧‧Buzzer 45‧‧‧Vibrator 46‧‧‧Light Part 48‧‧‧Communication interface 100‧‧‧Data matrix 101a‧‧‧Edge 101b‧‧‧Edge 101c‧‧Edge 101d‧‧‧Edge BK‧‧‧Background M‧‧‧Leave aside

In the attached drawings, 　　[FIG. 1] shows an explanatory diagram of the two-dimensional code of the first embodiment.　　[FIG. 2] A block diagram schematically illustrating an information code reading device for reading the two-dimensional code of the first embodiment.　　 [FIG. 3] A flowchart illustrating the flow of the reading process performed by the control unit of the information code reading device.　　[Fig. 4] An explanatory diagram showing the state where the two-dimensional code of the first embodiment is captured skewedly.　　[Fig. 5] An explanatory diagram illustrating the state of shooting with a part of the code area of the two-dimensional code shown in Fig. 1 missing.　　[Figure 6] An explanatory diagram showing the state where the previous two-dimensional code was taken skewedly.　　 [FIG. 7] An explanatory diagram showing the two-dimensional code of the first modification of the first embodiment.　　[Fig. 8] An explanatory diagram showing the state where the two-dimensional code of Fig. 7 adheres to dirt, etc., being captured.　　[FIG. 9] An explanatory diagram showing a two-dimensional code of a second modification of the first embodiment.　　[Fig. 10] An explanatory diagram showing the two-dimensional code of the second embodiment.　　 [FIG. 11] An explanatory diagram showing the two-dimensional code of the first modification of the second embodiment.　　 [FIG. 12] An explanatory diagram showing the two-dimensional code of the second modification of the second embodiment.　　[Figure 13] An explanatory diagram showing the two-dimensional code of the third embodiment.　　[Figure 14] An explanatory diagram showing the two-dimensional code of the fourth embodiment.　　[FIG. 15] An explanatory diagram for explaining the state of imaging with a part of the code area of the two-dimensional code of FIG. 14 missing.　　[FIG. 16] An explanatory diagram showing a display medium that displays the two-dimensional code of FIG. 14 in such a way that two of the three position detection patterns are positioned below.

1‧‧‧QR code

10‧‧‧Code area

10a‧‧‧Misumi

10b‧‧‧Misumi

10c‧‧‧Misumi

11a‧‧‧Position detection pattern

11b‧‧‧Position detection pattern

11c‧‧‧Position detection pattern

12‧‧‧Remaining corner

21‧‧‧Specific patterns

21a‧‧‧Pattern Department

21b‧‧‧Pattern Department

21c‧‧‧Pattern Department

21d‧‧‧Pattern Department

BK‧‧‧Background

DR‧‧‧Data recording area

EC‧‧‧Error correction symbol record area

Claims (19)

A type of two-dimensional code, which is located inside a rectangular code area. The unit for displaying plural information, that is, the grid is arranged in a matrix. The two-dimensional code is characterized by: three corners of the four corners in the aforementioned code area. A position detection pattern for detecting the position of the code area is provided; the position detection pattern and the specific pattern for specifying the code area are abutted on the edge of the code area or separated from the edge of the code area A certain distance apart, arranged on the outside of the edge. The two-dimensional code described in the first item of the scope of patent application, wherein the aforementioned specific pattern is in the vertical or horizontal direction of the code area, and has the same length in the vertical or horizontal direction of the grid 1 division. The width. For the two-dimensional code described in the first item of the scope of patent application, a margin of a predetermined width is provided between the aforementioned specific pattern and the edge of the aforementioned code area. As for the two-dimensional code described in item 3 of the scope of patent application, the margin of the aforementioned predetermined width is in the longitudinal or lateral direction of the aforementioned code area, which has the dimension of the longitudinal or lateral direction that is divided from the aforementioned grid 1 grid. The width of the same length. For the two-dimensional code described in any one of items 1 to 4 of the scope of patent application, the aforementioned specific pattern is formed by arranging the aforementioned grids of the same color. For the two-dimensional code described in any one of items 1 to 4 of the scope of patent application, the aforementioned specific pattern is formed by arranging a plurality of grids in such a way that the colors of adjacent grids are different. For example, the two-dimensional code described in any one of items 1 to 4 of the scope of patent application, wherein the aforementioned specific pattern is provided with a pair of pattern parts facing each other across the aforementioned code area; the aforementioned pair of pattern parts is A plurality of grids are arranged in such a way that the color of adjacent grids arranged outside the edge of the code area is different from the edge of the code area, or is spaced apart from the edge of the code area corresponding to each pattern. One column is composed separately. For example, the two-dimensional code described in any one of items 1 to 4 of the scope of patent application, wherein the aforementioned specific pattern is provided with the remaining corners that constitute the code area where the aforementioned position detection pattern is not provided. The two edges of the code area are constructed in such a way that the first pattern portion and the second pattern portion are orthogonal to each other. For example, the two-dimensional code described in any one of items 1 to 4 of the scope of patent application, wherein the aforementioned specific pattern has a plurality of specific patterns to form a substantial part of the code area surrounded by the plurality of specific patterns. Arrange the aforementioned specific patterns in a four-corner ring. For the two-dimensional code described in any one of items 2 to 4 of the scope of the patent application, each grid constituting the aforementioned plural grids is square; the width of each grid 1 division is equal to the aforementioned square shape One of the sides. For example, the two-dimensional code described in item 9 of the scope of patent application, in which the aforementioned specific pattern uses each grid to abut against the edge of the aforementioned code area, or is separated from the edge of the code area by a certain distance. The outer sides of the parts are arranged in a row to form the aforementioned four-corner ring shape, a part of the plurality of grids opposite to the position detection pattern is configured with grids of the same color, and the remaining grids are configured with different colors from adjacent grids. For the two-dimensional code described in item 9 of the scope of patent application, in the code area, the first fixed pattern that is different from the position detection pattern is composed of a plurality of grids and arranged; the specific pattern is abutted by each grid At the edge of the aforementioned code area, or spaced a certain distance from the edge of the code area, arranged on the outside of the edge The rows are arranged in a row to form the aforementioned four-corner ring shape, and the grids projecting the center of the first fixed pattern have a different color from the adjacent grids. For the two-dimensional code described in item 9 of the scope of patent application, in the code area, the second fixed pattern that is different from the position detection pattern is composed of a predetermined array of plural grids and is arranged; the aforementioned specific patterns use each The grid abuts on the edge of the code area, or is spaced a certain distance from the edge of the code area, and is arranged in a row outside the edge to form the aforementioned four-corner ring shape and project the position of the aforementioned second fixed pattern. The plural grids are formed in the manner of the aforementioned arrangement. For the two-dimensional code described in the second item of the scope of patent application, a margin of a predetermined width is provided between the aforementioned specific pattern and the edge of the aforementioned code area. For the two-dimensional code described in item 14 of the scope of the patent application, the margin of the aforementioned predetermined width is configured to have the same width as one grid division of the information unit grid in the code area. For the two-dimensional code described in item 5 of the scope of patent application, the aforementioned specific pattern is provided with two edges along the remaining corner of the code area that constitutes the aforementioned code area where the aforementioned position detection pattern is not provided. Part, the first pattern part and the second pattern part orthogonal to each other are constructed. For example, the two-dimensional code described in item 6 of the scope of patent application, wherein the aforementioned specific pattern is provided with two edges along the remaining corner of the code area that is not provided with the aforementioned position detection pattern. Part, the first pattern part and the second pattern part orthogonal to each other are constructed. For example, the two-dimensional code described in item 7 of the scope of patent application, wherein the aforementioned specific pattern is provided with two edges along the remaining corner of the code area that constitutes the aforementioned code area where the aforementioned position detection pattern is not provided. Part, the first pattern part and the second pattern part orthogonal to each other are constructed. A two-dimensional code reading device is a two-dimensional code reading device that optically reads a plurality of two-dimensional codes arranged in a matrix in a rectangular shape. The specific method is to specify the position of the aforementioned code area of the image taken by the aforementioned imaging means; and the interpretation method is to interpret the aforementioned two-dimensional code based on the aforementioned code area specified by the aforementioned specific method; the aforementioned two-dimensional code is In the three corners of the four corners of the code area, a position detection pattern for detecting the position of the code area is respectively arranged, and abuts against the edge of the code area determined by the position detection pattern, or with The edges of the code area are separated by a certain distance, and a specific pattern is arranged; The aforementioned specific means is based on the aforementioned position detection pattern and the aforementioned specific pattern to specify the position of the aforementioned code area of the aforementioned captured image.

Images