JP6989747B2 - Information reading device and information reading method - Google Patents

Description

The present invention relates to an information reading device that reads information from an information holding body, and an information reading method used in the information reading device.

An information reading device that reads information from an information holder is widely used in operations such as goods management in each field of physical distribution and distribution. In recent years, a compact and lightweight handy terminal has been used as an information reading device.

For example, as in Patent Document 1 below, a device that measures a distance from a handy terminal to an information holding body and starts an operation of reading information from the information holding body when the measured distance becomes equal to or less than a threshold value is disclosed. There is. Further, as in Patent Document 2 below, after reading the information from the information holding body, the reading result of reading the information from the information holding body is read according to the distance from the information reading unit acquired by the distance sensor to the information holding body. What determines whether or not to transmit to an external device is disclosed. For example, in Patent Document 2, when the distance acquired by the distance sensor is not included in the distance range for reading the information from the information holding body, the reading result is deleted.

Japanese Unexamined Patent Publication No. 2016-130951 Japanese Unexamined Patent Publication No. 2006-201921

By the way, various types of information holding bodies are used in operations such as goods management in each field of physical distribution and distribution. For example, the information holding body includes a one-dimensional symbol, a two-dimensional or higher-dimensional symbol (for example, a two-dimensional symbol and a three-dimensional symbol), an OCR symbol, or a non-contact IC tag. In the information reading device disclosed in Patent Document 1, the user operates the main body to select an information holding body for reading information each time, and reads information from the selected information holding body. Therefore, there is a problem that the operation of reading information by the user becomes complicated.

On the other hand, in the information reading device disclosed in Patent Document 2, after reading the information from the information holding body, it is determined whether or not to transmit the reading result to the external device according to the distance acquired by the distance sensor. That is, since the information reading device disclosed in Patent Document 2 performs an information reading operation before making a judgment according to the distance acquired by the distance sensor, if the acquired distance is not included in the distance range, There is a problem that the reading result is erased and the reading operation of the information is wasted.

The present invention has been made in consideration of such circumstances, and an object thereof is an information reading device capable of improving the efficiency of reading information from an information holding body, and the information reading device. The purpose is to provide the information reading method used.

In order to achieve the above object, the information reading device according to the present embodiment has an information reading unit that reads the information from the information holding body having the information, and acquires the distance from the information holding body to the information reading unit. The information reading unit includes a distance acquisition unit and a control unit that selects the type of the information holding body to be read according to the distance acquired by the distance acquisition unit. The information reading unit is the control unit. The information reading process corresponding to the type of the information holding body selected in is executed , and the information holding body is one of a one-dimensional symbol, a symbol having two or more dimensions, an OCR symbol, or a non-contact IC tag. The control unit is one of a plurality of distance ranges in which the distance is associated with each of the one-dimensional symbol, the two-dimensional or higher symbol, the OCR symbol, or the non-contact IC tag. When included in one, the type of the information holding body corresponding to the distance range including the distance is selected .

Further, in order to achieve the above object, the information reading method according to the present embodiment acquires the distance from the information holding body to the information reading device in the information reading method for acquiring information from the information holding body by the information reading device. A step of selecting the type of the information holding body to be read according to the acquired distance, and a step of executing an information reading process corresponding to the selected type of the information holding body. The information holding body is one of a one-dimensional symbol, a symbol of two or more dimensions, an OCR symbol, or a non-contact IC tag, and in the step of selecting the information, the distance is one-dimensional. When included in any one of a symbol, a symbol having two or more dimensions, the OCR symbol, or a plurality of distance ranges associated with each of the non-contact IC tags, the distance range including the distance is supported. Select the type of the information holding body to be used.

According to the information reading device and the information reading method, the information reading process corresponding to the type of the information holding body can be automatically switched according to the measured distance.

The information reading device and the information reading method according to the present embodiment can improve the efficiency of the work of reading information from the information holding body.

It is a block diagram which shows the information reading apparatus which concerns on 1st Embodiment. It is a figure which shows typically the plurality of distance ranges associated with each information holding body. It is a flowchart which shows the flow of reading information from an information holding body in the information reading apparatus which concerns on 1st Embodiment. It is a figure for demonstrating the method of measuring the distance from the image pickup unit to the information holding body in the control unit in 1st Embodiment. It is a figure which shows the display screen which displays the notification about the type of the selected information holding body. It is a figure which shows the display screen which displays the reading result. It is a flowchart which shows the flow of reading information from an information holding body in the information reading apparatus which concerns on 2nd Embodiment. It is a figure which shows typically the reading accuracy level set in the distance range shown in FIG. It is a figure which shows exemplary the reading method used when reading information from an information holding body.

Hereinafter, the information reading device according to the embodiment of the present invention will be described with reference to the drawings. It should be noted that this embodiment is not limited to the contents described below, and can be arbitrarily changed and implemented without changing the gist thereof. In addition, the drawings used in the description of the embodiments are all schematically showing the constituent members, and are partially emphasized, enlarged, reduced, or omitted in order to deepen the understanding, and the scale of the constituent members is scaled. It may not accurately represent the shape or shape.

(First Embodiment)
FIG. 1 is a block diagram showing an information reading device 1 according to the first embodiment. The information reading device 1 is a device for reading information from an information holder of a one-dimensional symbol, a two-dimensional or higher-dimensional symbol (for example, a two-dimensional symbol and a three-dimensional symbol), or an OCR symbol. The information reading device 1 shown in FIG. 1 includes an input unit 2, a communication unit 3, a display unit 4, a control unit 5, a storage unit 6, and an information reading unit 7. In the first embodiment, the input unit 2, the communication unit 3, the display unit 4, the control unit 5, the storage unit 6, and the information reading unit 7 are connected via the bus (communication path) 8.

The input unit 2 converts the input user's input operation into an electric signal and transmits it to the control unit 5. The input unit 2 in the first embodiment is composed of, for example, a number key and a switch capable of inputting alphanumerical characters for a function key. The user inputs instructions and information according to the operation guide displayed on the display unit 4 via the input unit 2.

The communication unit 3 communicates with an external device (for example, an external server) and exchanges information with the external device. The communication unit 3 in the first embodiment is used, for example, to update a program stored in the storage unit 6 or to transmit read information to a business system such as goods management in each field of physical distribution or distribution.

The display unit 4 displays various data according to the control by the control unit 5. For example, the display unit 4 displays operation guidance and acquired data according to the application execution program executed by the control unit 5. Further, the display unit 4 displays information on the type of the information holding body and the reading result output from the control unit 5. The display unit 4 has a display interface circuit and a display device. The display interface circuit converts the data representing the display target into a video signal. The video signal is supplied to the display device. The display device displays a screen based on a video signal representing a display target. As the display device, for example, a liquid crystal display (LCD) or any other display known in the art can be appropriately used.

The control unit 5 includes a predetermined processor such as a CPU (Central Processing Unit) and an MPU (Micro Processing Unit) as hardware resources. The processor included in the control unit 5 reads out the program stored in the storage unit 6. The control unit 5 executes various processes by executing the read program. Specifically, the processor of the control unit 5 reads out the integrated control program stored in the storage unit 6. The processor of the control unit 5 comprehensively controls each configuration included in the information reading device 1 by executing the read integrated control program. Further, the processor of the control unit 5 reads out the application execution program stored in the storage unit 6. The processor of the control unit 5 outputs the operation screen of the information reading device 1 to the display unit 4 by executing the read application execution program.

Further, the control unit 5 reads out the distance measurement program stored in the storage unit 6. The control unit 5 measures the distance from the information reading unit 7 to the information holding body by executing the read distance measuring program. Specifically, the control unit 5 measures the distance from the image pickup unit 9 constituting the information reading unit 7 to the information holding body.

Further, the control unit 5 reads out the read control program stored in the storage unit 6. By executing the read reading control program, the control unit 5 selects the type of the information holding body to be read according to the measured distance from the information reading unit 7 to the information holding body, and holds the selected information. The information reading unit 7 is controlled so as to execute the information reading process corresponding to the body type.

Here, the information reading process is a series of processes executed by the information reading unit 7 for reading information from the information holding body. Specifically, as a series of processes, a binarization process in which the pixel value of the image captured by the image pickup unit 9 is set to 0 or 1, and labeling in which the same number is assigned to consecutive pixels of the image subjected to the binarization process. Area extraction processing for extracting an area corresponding to an information holding body of the type selected by the control unit 5 from an image subjected to processing and labeling processing, expansion processing for expanding pixels, reduction processing for reducing pixels, and the like. Image processing is selected or combined. The information reading process is set for each information holder of a one-dimensional symbol, a two-dimensional or higher-dimensional symbol, or an OCR symbol. The plurality of information reading processes are stored in advance in the storage unit 6.

Specifically, the information reading unit 7 in the first embodiment executes a binarization process as an information reading process for reading information from a one-dimensional symbol. Further, the information reading unit 7 performs binarization processing, expansion processing, reduction processing, labeling processing, and two-dimensional symbol area extraction for extracting the two-dimensional symbol as information reading processing for reading information from the two-dimensional symbol. Execute the process. Further, the information reading unit 7 executes binarization processing, labeling processing, and OCR symbol area extraction processing for extracting the OCR symbol as information reading processing for reading information from the OCR symbol.

The storage unit 6 includes a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disc Drive) capable of storing data, and an SSD (Solid State Drive). In the first embodiment, the storage area of the storage unit 6 exists in the information reading device 1, but may be in an external storage device (not shown) connected via the communication unit 3. The storage unit 6 stores, for example, the integrated control program, the application execution program, the distance measurement program, and the read control program. Further, the storage unit 6 stores the plurality of information reading processes in advance. Further, the storage unit 6 stores in advance the distance range associated with each of the information holding bodies of the one-dimensional symbol, the two-dimensional or higher symbol, or the OCR symbol.

Here, the distance range is the range of the distance L from the measured image pickup unit 9 to the information holding body T associated with the information holding body such as a one-dimensional symbol, a two-dimensional or higher-dimensional symbol, or an OCR symbol. Is. In the information reading device 1 according to the first embodiment, a plurality of distance ranges associated with each of the information holding bodies T are set. FIG. 2 is a diagram schematically showing a plurality of distance ranges associated with each of the information holding bodies T. As shown in FIG. 2, in the information reading device 1 according to the first embodiment, a plurality of distance ranges α, β, γ, δ, ε, and ζ are set. The distance range δ is a range in which the distance range β and the distance range γ overlap. The plurality of distance ranges α, β, γ, δ, ε, and ζ in the first embodiment are set with reference to the optimum distance for reading information from each of the information holding bodies T, for example. Specifically, the plurality of distance ranges α, β, γ, δ, ε, and ζ are set to have a predetermined width with the optimum distance for reading information from each of the information holding bodies T as the median. Will be done.

In the first embodiment, the distance range α is associated with the OCR symbol. When the distance L (distance L1 shown in FIG. 2) from the measured image pickup unit 9 to the information holding body T is included in the distance range α, the control unit 5 reads information from the OCR symbol corresponding to the distance range α. The information reading unit 7 is controlled so as to execute the information reading process.

Further, the distance range β is associated with a two-dimensional symbol. When the distance L (distance L2 shown in FIG. 2) from the measured image pickup unit 9 to the information holding body T is included in the distance range β, the control unit 5 reads information from the two-dimensional symbol corresponding to the distance range β. The information reading unit 7 is controlled so as to execute the information reading process of.

Further, the distance range γ is associated with a one-dimensional symbol. When the distance L (distance L3 shown in FIG. 2) from the measured image pickup unit 9 to the information holding body T is included in the distance range γ, the control unit 5 reads information from the one-dimensional symbol corresponding to the distance range γ. The information reading unit 7 is controlled so as to execute the information reading process of.

Further, the distance range δ is associated with a one-dimensional symbol and a two-dimensional symbol. When the distance L (distance L4 shown in FIG. 2) from the measured image pickup unit 9 to the information holding body T is included in the distance range δ, the control unit 5 starts from the one-dimensional symbol and the two-dimensional symbol corresponding to the distance range δ. The information reading unit 7 is controlled so as to execute the information reading process for reading the information. In such a case, in the first embodiment, the information reading process for reading the information from the one-dimensional symbol and the information reading process for reading the information from the two-dimensional symbol are executed separately. ..

In the first embodiment, when the measured distance L from the image pickup unit 9 to the information holding body T (distance L5 shown in FIG. 2) is included in the distance range ε, or from the measured image pickup unit 9 to the information holding body T. When the distance L to (the distance L6 shown in FIG. 2) is included in the distance range ζ, none of the information holding bodies T can be recognized. Therefore, the control unit 5 does not select the type of the information holding body T.

In the first embodiment, by associating the above distance range with the information holding body T such as a one-dimensional symbol, a two-dimensional or higher-dimensional symbol, or an OCR symbol, information can be read from which distance to the information holding body T to be read. It is possible to know in advance whether or not the operation should be performed. This makes it easier for the user to adjust the distance L to the distance range associated with the information holding body T when the user performs the work of reading the information from the information holding body T. That is, the information reading device 1 according to the first embodiment can improve the efficiency of the work of reading information from the information holding body T.

The information reading unit 7 executes an information reading process for reading information according to the type of the information holding body T selected by the control unit 5. The information reading unit 7 in the first embodiment includes an imaging unit 9 and a decoding unit 10. The image pickup unit 9 takes an image so as to include at least one type of information holding body T in the image pickup field of view. The image captured by the image pickup unit 9 includes a region corresponding to at least one type of information holding body T. The image captured by the image pickup unit 9 is stored in the storage unit 6. The image pickup unit 9 in the first embodiment includes, for example, an optical lens (not shown), a CMOS sensor, lighting, a laser beam irradiator, and an image pickup control unit (not shown). The CMOS sensor constitutes a light receiving unit together with the optical lens. The illumination illuminates the information holding body T at the time of imaging by the CMOS sensor. As the lighting, for example, an LED is used. The laser light irradiator irradiates a laser beam as a reference for measuring the distance from the image pickup unit 9 to the information holding body T. Under the control of the control unit 5, the image pickup control unit controls image pickup by the CMOS sensor, lighting on / off, and laser light irradiation by the laser light irradiator.

The decoding unit 10 extracts the information holding body T of the type selected by the control unit 5 from the image stored in the storage unit 6. Further, the decoding unit 10 decodes the information from the extracted information holding body T according to a predetermined standard. The decoding unit 10 outputs the decoded information to the display unit 4. A predetermined standard is set for each information holding body T of a one-dimensional symbol, a two-dimensional or higher symbol, or an OCR symbol.

Here, in the information reading device 1 according to the first embodiment, a distance acquisition unit for acquiring the distance from the information holding body to be read to the information reading unit 7 is configured by the control unit 5 and the imaging unit 9. .. That is, the information reading device 1 according to the first embodiment measures the distance from the information holding body T to the information reading unit 7. The distance from the target information holding body T to the information reading unit 7 is not measured by the information reading device 1, but may be measured by an external device. In such a case, the measurement result is acquired via the communication unit 3, and the communication unit 3 functions as a distance acquisition unit for acquiring the distance from the information holding body T to the information reading unit 7. Become.

Here, the flow of reading information from the information holding body T in the information reading device 1 according to the first embodiment will be described in detail with reference to FIGS. 3 to 6. FIG. 3 is a flowchart showing a flow of reading information from the information holding body T in the information reading device 1 according to the first embodiment. FIG. 4 is a diagram for explaining a method of measuring the distance L from the image pickup unit 9 to the information holding body T in the control unit 5 in the first embodiment.

First, in step Sa1, the information reading unit 7 of the information reading device 1 irradiates the information holding body T with laser light from the laser light irradiator 12 of the imaging unit 9. For example, in the first embodiment, a button for instructing the start of distance measurement operation is provided in the input unit 2. When the button for instructing the start of the distance measuring operation is pressed, the information reading unit 7 irradiates the information holding body T with the laser beam from the laser beam irradiator 12. At this time, the information reading unit 7 irradiates at least one type of information holding body T with a laser. In step Sa2, the image pickup unit 9 of the information reading unit 7 takes an image so as to include at least one type of information holding body T irradiated with the laser beam in the image pickup field of view.

In step Sa3, the control unit 5 of the information reading device 1 measures the distance L from the image pickup unit 9 to the information holding body T based on the image captured in step Sa2. Specifically, as shown in FIG. 4, the distance L from the image pickup unit 9 to the information holding body T can be obtained by the following equation (1).

L = Wa / {tanθ2- (Mdtanθ1) / Xd} ... (1)
Wa: Distance between the center of the CMOS sensor 11 and the center of the laser beam irradiator Md: Center position Xd and the amount of deviation of the laser beam irradiation position Mp Xd: Center position of the horizontal field of view of the CMOS sensor 11 θ1: CMOS sensor 11 Horizontal viewing angle θ0 1/2 angle θ2: Optical axis LL of laser light irradiator 12 and field center line CL of CMOS sensor 11
Eggplant angle

In step Sa4, the control unit 5 selects the type of the information holding body T according to the measured distance L. In step Sa5, the control unit 5 outputs a notification regarding the type of the selected information holding body T to the display unit 4. The display unit 4 displays a notification regarding the type of the information holding body T output from the control unit 5. FIG. 5 is a diagram showing a display screen for displaying a notification regarding the type of the selected information holding body T. The display screen shown in FIG. 5 includes an area A1 and an area A2. The area A1 is an area for displaying whether or not the information can be read from the information holding body T. If information can be read from at least one of a one-dimensional symbol, a two-dimensional or higher-dimensional symbol, or an OCR symbol, the area A1 is displayed as readable. On the other hand, if the information cannot be read from any of the one-dimensional symbol, the two-dimensional or higher-dimensional symbol, or the OCR symbol, the area A1 is displayed as unreadable.

Further, the area A2 is an area for displaying a notification regarding the type of the information holding body T whose information can be read, or a notification notifying that the information holding body T cannot be recognized. For example, when the measured distance L is included in the distance range α shown in FIG. 2, as shown in FIG. 5A, a notification notifying that information can be read from the OCR symbol is displayed in the area A2. To. As shown in FIG. 5B, when the measured distance L is included in the distance range β shown in FIG. 2, a notification is displayed in the area A2 notifying that information can be read from the two-dimensional symbol. .. As shown in FIG. 5 (c), when the measured distance L is included in the distance range γ shown in FIG. 2, a notification indicating that information can be read from the one-dimensional symbol is displayed in the area A2. .. When the measured distance L is included in the distance range δ shown in FIG. 2, as shown in FIG. 5 (d), the notification that the information can be read from each of the one-dimensional symbol and the two-dimensional symbol is in the area. It is displayed on A2. When the measured distance L is included in the distance range ε shown in FIG. 2 or the distance range ζ, a notification notifying that the information holding body T cannot be recognized is displayed in the area A2 as shown in FIG. 5 (e). ..

In step Sa6, the control unit 5 determines whether or not there is a trigger to start reading the information corresponding to the type of the selected information holding body T. When the trigger is present (Yes in step Sa6), in step Sa7, the image pickup unit 9 of the information reading unit 7 takes an image so as to include at least one type of information holding body T in the image pickup field of view. For example, in the first embodiment, a button for giving an information reading start instruction is provided in the input unit 2. The image pickup unit 9 of the information reading unit 7 takes an image so as to include at least one type of information holding body T in the imaging field of view when the button for instructing the information reading start is pressed as the trigger. If there is no such trigger (No in step Sa6), the process returns to step Sa1.

In step Sa8, the information reading unit 7 reads from the storage unit 6 the information reading process corresponding to the type of the information holding body T selected by the control unit 5. The information reading unit 7 executes the information reading process read from the storage unit 6. Here, when the image captured in step Sa7 includes a region corresponding to the information holding body T of the type selected in the control unit 5, the information reading unit 7 reads the information contained in the information holding body T. Is output as. On the other hand, the information reading unit 7 cannot recognize the region corresponding to the information holding body T of the type selected by the control unit 5 from the image captured in step Sa7, or the image captured in step Sa7. Does not output the reading result when the area corresponding to the information holding body T of the type selected by the control unit 5 is not included. In other words, the information reading unit 7 cannot recognize the information holding body T of the type selected by the control unit 5 from the image, or holds the information of the type selected by the control unit 5 in the image. If the body T is not shown, the reading result is not output. The reason why the information holding body T of the type selected by the control unit 5 cannot be recognized from the image is, for example, that the information holding body T is not imaged at a correct distance or the information holding body T is not captured. It is possible that it is missing.

In step Sa9, the control unit 5 determines whether or not the information reading process by the information reading unit 7 is successful. The control unit 5 determines, for example, that the information reading process by the information reading unit 7 is successful when the reading result is output from the information reading unit 7. When the information reading process by the information reading unit 7 is successful (Yes in step Sa9), in step Sa10, the control unit 5 outputs the reading result to the display unit 4. The display unit 4 displays the reading result output from the control unit 5.

FIG. 6 is a diagram showing a display screen for displaying the reading result. The display screen shown in FIG. 6 includes a region Ar. The area Ar is an area for displaying a notification regarding the information read from the information holding body T. For example, when the image captured in step Sa7 includes a region corresponding to the OCR symbol and the information reading unit 7 executes the information reading process corresponding to the OCR symbol, as shown in FIG. 6A, the OCR A notification indicating the information read from the symbol is displayed in the area Ar. As shown in FIG. 6B, when the image captured in step Sa7 includes a region corresponding to the two-dimensional symbol and the information reading unit 7 executes the information reading process corresponding to the two-dimensional symbol, two A notification indicating the information read from the dimensional symbol is displayed in the area Ar. As shown in FIG. 6 (c), when the image captured in step Sa7 includes a region corresponding to the one-dimensional symbol and the information reading unit 7 executes the information reading process corresponding to the one-dimensional symbol, the primary A notification notifying the information read from the original symbol is displayed in the area Ar. As shown in FIG. 6D, the image captured in step Sa7 includes a region corresponding to the one-dimensional symbol and the two-dimensional symbol, and the information reading unit 7 reads the information corresponding to the one-dimensional symbol and the two-dimensional symbol. When the process is executed, a notification notifying the information read from each of the one-dimensional symbol and the two-dimensional symbol is displayed in the area Ar.

When the information reading process by the information reading unit 7 fails (No in step Sa9), the information holding body T of the type selected by the control unit 5 cannot be recognized from the image, or the image is controlled. It is conceivable that the information holding body T of the type selected in Part 5 is not shown. Therefore, the process returns to step Sa7. Through the above process, the information reading device 1 can present the information read from the information holding body T to the user.

As described above, the information reading device 1 according to the first embodiment acquires the distance from the information holding body T to the information reading unit 7 in the information reading device 1 having the information reading unit 7 for reading the information from the information holding body T having the information. Then, the type of the information holding body T is selected according to the acquired distance. The information reading unit 7 executes an information reading process for reading information from the information holding body T, which corresponds to the type of the selected information holding body T.

According to the above configuration, the information reading device 1 according to the first embodiment can automatically switch the information reading process corresponding to the type of the information holding body T according to the measured distance. Thus, the information reading device 1 according to the first embodiment can improve the efficiency of the work of reading information from the information holding body T.

(Second Embodiment)
In the information reading device 1 according to the first embodiment, the distance ranges α, β, γ, δ, ε, and ζ are set based on the optimum distance for reading information from each of the information holding bodies T. .. That is, when the information is read from the information holding body T at a position far from the optimum distance for reading the information even within the corresponding distance range, the information holding body T is read from the information holding body T at a position close to the optimum distance for reading the information. Compared with the case of reading the information, the reading accuracy of the information is lowered and the reliability of the reading result is lowered.

Therefore, the information reading device 1 according to the second embodiment automatically adjusts the reading accuracy of the information according to the measured distance L in order to secure the reading accuracy of the information at a position away from the optimum distance. do. Here, since the configuration of the information reading device 1 according to the second embodiment is substantially the same as the configuration of the information reading device 1 according to the first embodiment, detailed description thereof will be omitted. In the second embodiment, in the flow of reading information from the information holding body T in the first embodiment, a part different from the first embodiment will be mainly described.

FIG. 7 is a flowchart showing a flow of reading information from the information holding body T in the information reading device 1 according to the second embodiment. It should be noted that detailed description of the description overlapping with the flowchart shown in FIG. 3 will be omitted.

First, in step Sb1, the information reading unit 7 of the information reading device 1 irradiates the information holding body T with laser light from the laser light irradiator 12 of the imaging unit 9. In step Sb2, the image pickup unit 9 of the information reading unit 7 takes an image so as to include at least one type of information holding body T irradiated with the laser beam in the image pickup field of view. In step Sb3, the control unit 5 of the information reading device 1 measures the distance L from the image pickup unit 9 to the information holding body T based on the image captured in step Sb2. In step Sb4, the control unit 5 selects the type of the information holding body T according to the measured distance L. In step Sb5, the control unit 5 selects the reading accuracy level according to the measured distance L. That is, the information reading device 1 according to the second embodiment automatically adjusts the reading accuracy of information by selecting the reading accuracy level according to the measured distance L.

Here, the reading accuracy level defines a reading method for reading information from the information holding body T and the number of times the information is read, and is set for each of a plurality of ranges in which one distance range is divided. In the information reading device 1 according to the second embodiment, a plurality of reading accuracy levels according to the distance are set in one distance range.

FIG. 8 is a diagram schematically showing a reading accuracy level set in the distance range shown in FIG. Note that FIG. 8 describes, as an example, the reading accuracy level set in the distance range γ. Further, the reading accuracy level in the second embodiment is set so as to increase in the order of A → B → C → D. As shown in FIG. 8, the distance range shown in FIG. 2 is divided into a plurality of ranges, and the reading accuracy level is set for each of the plurality of ranges.

Specifically, the information reading unit 7 reads information from the information holding body T by adopting a plurality of reading methods. FIG. 9 is a diagram schematically showing a reading method used when reading information from the information holding body T. For example, as shown in FIG. 9A, the information reading unit 7 reads information from the information holding body T by adopting a left-right scanning method of reading information from the information holding body T by shaking the laser left and right. Further, as shown in FIG. 9B, the information reading unit 7 adopts a line scan method of reading information from the information holding body T on different lines to read information from the information holding body T. Further, the information reading unit 7 increases the number of times the information is read from the information holding body T, and reads the information from the information holding body T.

When the distance L is included in the distance range of the reading accuracy level A shown in FIG. 8, the information reading unit 7 in the second embodiment obtains information in the line scan method with respect to the image captured by the imaging unit 9. Perform a read.

Further, when the distance L is included in the distance range of the reading accuracy level B shown in FIG. 8, the information reading unit 7 executes information reading by the line scanning method for the image captured by the imaging unit 9. do. Further, the information reading unit 7 executes information reading by the left-right scanning method for the image captured by the imaging unit 9. Further, the information reading unit 7 compares the reading result of the information by the line scanning method and the reading result of the information by the left and right scanning method. By comparing the reading results obtained by different scanning methods, it is verified whether the output reading results are correct.

Further, when the distance L is included in the distance range of the reading accuracy level C shown in FIG. 8, the information reading unit 7 reads information from the first image captured by the imaging unit 9 by the left / right scanning method. To execute. Further, the information reading unit 7 executes information reading by the left-right scanning method for the second image captured by the imaging unit 9 at a timing different from that of the first image. The first image and the second image are images taken within the same distance range. Further, the information reading unit 7 compares the reading result of the information in the left / right scanning method for the first image and the reading result of the information in the left / right scanning method for the second image. By comparing the reading results obtained from a plurality of images taken at different timings, it is verified whether or not the images are correctly taken within the set distance range.

Further, when the distance L is included in the distance range of the reading accuracy level D shown in FIG. 8, the information reading unit 7 reads information from the first image captured by the imaging unit 9 by the left / right scanning method. To execute. Further, the information reading unit 7 reads information on the first image by the line scan method. Further, the information reading unit 7 executes information reading by the left-right scanning method for the second image captured by the imaging unit 9 at a timing different from that of the first image. Further, the information reading unit 7 reads information on the second image by the line scan method. Further, the information reading unit 7 compares the reading result of the information in the left-right scanning method and the line scanning method for the first image, and the reading result of the information in the left-right scanning method and the line scanning method for the second image. By comparing the reading results obtained from a plurality of images taken at different timings, it is verified whether or not the images are correctly taken within the set distance range. In addition, by comparing the reading results obtained by different scanning methods, it is verified whether the output reading results are correct.

In step Sb6, the control unit 5 outputs a notification regarding the type of the selected information holding body T to the display unit 4. In step Sb7, the control unit 5 determines whether or not there is a trigger to start reading the information corresponding to the type of the selected information holding body T. When the trigger is present (Yes in step Sb7), in step Sb8, the image pickup unit 9 of the information reading unit 7 takes an image so as to include at least one type of information holding body T in the image pickup field of view. If there is no such trigger (No in step Sb7), the process returns to step Sb1.

In step Sb9, the information reading unit 7 reads from the storage unit 6 the information reading process corresponding to the type of the information holding body T selected by the control unit 5 and the reading accuracy level. The information reading unit 7 executes the information reading process read from the storage unit 6. In step Sb10, the control unit 5 determines whether or not the information reading process by the information reading unit 7 is successful.

When the information reading process by the information reading unit 7 is successful (Yes in step Sb10), in step Sb11, the control unit 5 determines whether or not the information reading end condition according to the selected reading level is satisfied. When the information reading process by the information reading unit 7 fails (No in step Sb10), the information holding body T of the type selected by the control unit 5 cannot be recognized from the image, or the image is controlled. It is conceivable that the information holding body T of the type selected in Part 5 is not shown. Therefore, the process returns to step Sb8.

Here, the information reading end condition when the reading level A is selected in the control unit 5 is, for example, that the image pickup unit 9 takes images a number of times according to the reading level A, and the information reading unit 7 takes information. It is determined that the reading process is successful. Further, the information reading end condition when the reading level B is selected in the control unit 5 is, for example, a reading in which the imaging unit 9 has taken images a number of times according to the reading level B and acquired by a different scanning method. The results are compared and the output reading results are correct. Further, the information reading end condition when the reading level C is selected in the control unit 5 is, for example, a plurality of images taken by the imaging unit 9 according to the reading level C and imaged at different timings. The reading results obtained from the images are compared, and the images are correctly captured within the set distance range. Further, the information reading end condition when the reading level D is selected in the control unit 5 is, for example, a plurality of images taken by the imaging unit 9 according to the reading level D and imaged at different timings. The reading results obtained from the images are compared, the images are correctly captured within the set distance range, and the reading results obtained by different scanning methods are compared, and the output reading results are correct. ..

When the information reading end condition corresponding to the selected reading level is satisfied (Yes in step Sb11), in step Sb12, the control unit 5 outputs the reading result to the display unit 4. If the information reading end condition corresponding to the selected reading level is not satisfied (No in step Sb11), the process returns to step Sb8. Through the above process, the information reading device 1 according to the second embodiment can present the information read from the information holding body T to the user.

As described above, the information reading device 1 according to the second embodiment acquires the distance from the information holding body T to the information reading unit 7 in the information reading device 1 having the information reading unit 7 for reading the information from the information holding body T having the information. Then, the type of the information holding body T is selected according to the acquired distance. The information reading unit 7 executes an information reading process for reading information from the information holding body T, which corresponds to the type of the selected information holding body T.

According to the above configuration, the information reading device 1 according to the second embodiment can automatically switch the information reading process corresponding to the type of the information holding body T according to the measured distance. Thus, the information reading device 1 according to the second embodiment can improve the efficiency of the work of reading information from the information holding body T.

Further, the information reading device 1 according to the second embodiment can improve the reading accuracy of information at a position away from the optimum distance for reading information by setting the reading accuracy level. Further, since the information reading device 1 according to the second embodiment can improve the reading accuracy of the information at a position away from the optimum distance for reading the information, the information is read at any position in the above distance range. However, it is possible to approach the reading accuracy of the information at a position close to the optimum distance for reading the information. Therefore, the information reading device 1 according to the second embodiment can improve the reliability of the reading result of the entire distance range. The information reading process defined for each reading accuracy level is exemplary, and the information reading process can be changed to an arbitrary information reading process by the user via the input unit 2. ..

Here, in the first embodiment and the second embodiment, when the information reading unit 7 reads information from the information holding body T at a position close to the optimum distance for reading the information, the information reading unit 7 starts from the optimum distance for reading the information. The process of reading information is simplified as compared with the case of reading information from the information holding body T at a distant position. That is, when the information reading device 1 according to the first embodiment and the second embodiment reads information from the information holding body T at a position close to the optimum distance for reading the information, the reading result can be quickly acquired.

Further, in the information reading device 1 according to the first embodiment and the second embodiment, the farther the distance from the image pickup unit 9 to the information holding body T is, the more the information holding body T included in the image captured by the image pickup unit 9. The proportion of the area corresponding to is small. Therefore, the information reading device 1 according to the first embodiment and the second embodiment narrows the range to be subject to image processing according to the measured distance. As a result, the information reading device 1 according to the first embodiment and the second embodiment can reduce the range in which the image processing is executed, so that the reading time can be shortened. Further, in the information reading device 1 according to the first embodiment and the second embodiment, the detection range of the CMOS sensor 11 included in the image pickup unit 9 is narrowed according to the measured distance. As a result, the information reading device 1 according to the first embodiment and the second embodiment can reduce the range in which the image processing is executed, so that the reading time can be shortened.

Further, in the information reading device 1 according to the first embodiment and the second embodiment, a notification unit may be provided to notify which of the plurality of distance ranges the measured distance L is included in. .. For example, the notification unit has a mark laser light irradiator that is separate from the above laser light irradiator, and the intensity, blinking, width change, or color of the laser output from the mark laser light irradiator. Using a method such as modification, the measured distance is notified which of the plurality of distance ranges is included. Thereby, the information reading device 1 according to the first embodiment and the second embodiment can intuitively grasp which distance range the measured distance L is included in. Here, the information reading device 1 according to the first embodiment and the second embodiment may display on the display unit 4 which distance range the measured distance L is included in.

Further, in the information reading device 1 according to the first embodiment and the second embodiment, the distance range may be set in consideration of factors such as the type of the information holding body T and the size of the information holding body T. good. For example, the information holding body used on the customer side is read into the information reading device 1 for teaching. The distance range in which information can be read from the information holding body for teaching may be automatically set as the distance range corresponding to the information holding body. As a result, the information reading device 1 according to the first embodiment and the second embodiment can eliminate the complexity of setting the distance range. The distance range can be set by the user via the input unit 2.

Further, in the first embodiment and the second embodiment, the button for instructing the start of the distance measurement operation in step Sa2 and step Sb2 is a two-step pressing method, and the button for instructing the start of the distance measurement operation is further added. By pressing the button, the information reading start instruction in step Sa6 and step Sb7 may be given.

In the information reading device 1 according to the first embodiment and the second embodiment, the decoding of the information holding body T is performed by the decoding unit 10. However, the information reading device 1 according to the first embodiment and the second embodiment is not limited to this. For example, the information reading device 1 according to the first embodiment and the second embodiment may perform decoding of the information holding body T in the control unit 5.

Further, in the information reading device 1 according to the first embodiment and the second embodiment, the control unit 5 selects the type of the information holding body T according to the distance measured from the image captured by the imaging unit 9. is doing. However, the information reading device 1 according to the first embodiment and the second embodiment is not limited to this. For example, the information reading device 1 according to the first embodiment and the second embodiment may further install a distance sensor and select the type of the information holding body T according to the distance measured by the distance sensor. .. Further, the distance may be acquired from an external device connected to the information reading device 1 via the communication unit 3, and the type of the information holding body T may be selected according to the acquired distance.

Further, in the first embodiment and the second embodiment, the information holding bodies to be read are one-dimensional symbols, two-dimensional symbols, and OCR symbols, but the present invention is not limited thereto. For example, it is possible to target a display and a component in which the information holding body can hold various types of information such as a symbol having two or more dimensions or a contact IC tag. When such other information holding bodies are also targeted, various settings related to the other information holding bodies (that is, settings related to the distance range and settings related to the combined processing) are made to the information reading device 1. ..

Further, the term "predetermined processor" used in the above description means, for example, a dedicated or general-purpose processor or the like. Further, each component (each processing unit) of the first embodiment and the second embodiment is not limited to a single processor, and may be realized by a plurality of processors. Further, a plurality of components (a plurality of processing units) may be realized by a single processor.

1 Information reader 2 Input unit 3 Communication unit 4 Display unit 5 Control unit 6 Storage unit 7 Information reader 8 Bus (communication path)
9 Imaging unit 10 Decoding unit 11 CMOS sensor 12 Laser light irradiator

Claims (5)

In an information reading device having an information reading unit that reads the information from an information holding body having information.
A distance acquisition unit that acquires the distance from the information holding body to the information reading unit, and
A control unit for selecting the type of the information holding body to be read according to the distance acquired by the distance acquisition unit is provided.
The information reading unit executes information reading processing corresponding to the type of the information holding body selected by the control unit .
The information holding body is one of a one-dimensional symbol, a two-dimensional or higher-dimensional symbol, an OCR symbol, or a non-contact IC tag.
The control unit is included in any one of a plurality of distance ranges in which the distance is associated with each of the one-dimensional symbol, the two-dimensional or higher symbol, the OCR symbol, or the non-contact IC tag. In the case, an information reading device that selects the type of the information holding body corresponding to the distance range including the distance . The control unit corresponds to each of the at least two distance ranges when a part of at least two distance ranges in the plurality of distance ranges overlaps and the distances are included in the overlapping parts. The information reading device according to claim 1 , which selects the type of information holding body. The information reading unit divides one distance range into a plurality of ranges, sets a reading method for reading the information for each of the plurality of ranges, and sets a reading accuracy level that determines the number of times the information is read. Item 2. The information reading device according to item 1 or 2 . The information reading device according to any one of claims 1 to 3 , further comprising a notification unit for notifying which distance range the distance is included in the plurality of distance ranges. In the information reading method of acquiring information from an information holder by an information reading device,
The process of acquiring the distance from the information holding body to the information reading device, and
The process of selecting the type of the information holding body to be read according to the acquired distance, and
A step of executing an information reading process corresponding to the selected type of the information holding body is provided .
The information holding body is one of a one-dimensional symbol, a two-dimensional or higher-dimensional symbol, an OCR symbol, or a non-contact IC tag.
The selected step is included in any one of a plurality of distance ranges in which the distance is associated with each of the one-dimensional symbol, the two-dimensional or higher symbol, the OCR symbol, or the non-contact IC tag. If so, an information reading method for selecting the type of the information holding body corresponding to the distance range including the distance .

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