Display device, display device control method, and program

Abstract

To provide a display unit that can improve the accuracy of reading of code information performed by a reading device when the relative position to the reading device changes.SOLUTION: A display unit 101 displays code information on a display part 201 of the display unit 101, and makes a determination as to a function of a reading device 102 to read the code information. Based on a result of the determination as to the function of the reading device 102, the display unit 101 determines whether to perform predetermined display control of improving the accuracy of reading of the code information performed by the reading device 102 when the relative position to the reading device 102 changes.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a display device, a control method for a display device, and a program. [Background technology]

[0002] Display devices that display code information such as QR Code (registered trademark), and reading devices that read code information displayed on the display devices, have been put to practical use. Related technology is proposed in Patent Document 1. In Patent Document 1, different forms of code information are displayed on the display device depending on the results of comparing the tilt of the display device with the tilt of the reading surface of the reading device. As a result, when the relative positions of the display device and the reading device change, the shape of the code information displayed on the display device can be corrected in accordance with this change in relative position, thereby improving the reading accuracy of the reading device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-46878 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the control of correcting the shape of the code information based on the relative positions of the display device and the reading device as described above may not improve the reading accuracy of the reading device. For example, if the reading device has a shake correction function to correct hand shake, the shake correction function of the reading device may work in conjunction with the control of correcting the shape of the code information by the display device, preventing the reading device from properly reading the code information. Furthermore, when reading in a dark place, for example, the reading device needs to set a longer reading time than usual to obtain the amount of light required for reading. However, as the reading time increases, the reading device becomes more susceptible to changes in the relative positions of the display device and the reading device. For example, if the display device repeatedly corrects the shape of the code information in response to changes in the relative positions of the display device and the reading device that occur during the reading time, the reading device will not be able to properly read the code information.

[0005] An object of the present invention is to provide a display device, a control method for a display device, and a program that can improve the accuracy of reading code information by a reading device when the relative position between the display device and the reading device changes. [Means for solving the problem]

[0006] In order to achieve the above object, the display device of the present invention comprises a display means, a display control means for controlling the display means to display code information, and a judgment means for making a judgment regarding the function of a reading device that reads the code information, and is characterized in that the display control means determines whether or not to perform a predetermined display control that improves the reading accuracy of the code information by the reading device based on the result of the judgment by the judgment means. [Effects of the Invention]

[0007] According to the present invention, it is possible to improve the accuracy of reading code information by a reading device when the relative position with respect to the reading device changes. [Brief explanation of the drawings]

[0008] [Figure 1]1 is a side view of a code reading system including a display device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a block diagram schematically showing the configuration of each of the display device and reading device of FIG. [Figure 3] 3 is a flowchart showing the procedure of a display control process executed by the display control unit of FIG. 2. [Figure 4] FIG. 4 is a diagram for explaining the correction of code information in step S303 of FIG. 3. [Figure 5] FIG. 10 is a block diagram schematically illustrating a configuration of a display device according to a second embodiment of the present invention. [Figure 6] 6 is a flowchart showing the procedure of a display control process executed by the display control unit of FIG. 5. [Figure 7] FIG. 7 is a diagram for explaining the control of the brightness of the code information in step S602 of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. First, a display device and a control method thereof according to a first embodiment of the present invention will be described.

[0010] Fig. 1 is a side view of a code reading system 100 including a display device 101 according to an embodiment of the present invention. In Fig. 1, the code reading system 100 includes the display device 101 and a reading device 102. In the code reading system 100, the reading device 102 reads code information displayed on a display unit 201 of the display device 101 (described later in Fig. 2). The code information is an image in which various information has been converted into a code in a predetermined format, and is, for example, a one-dimensional code such as a hologram or a barcode, a two-dimensional code such as a QR code, or a three-dimensional code such as a PM code.

[0011] Fig. 2 is a block diagram showing a schematic configuration of the display device 101 and the reading device 102 in Fig. 1. In Fig. 2, the display device 101 includes a display unit 201, a display control unit 202, a detection unit 203, and a determination unit 204. The display control unit 202 is connected to the display unit 201, the detection unit 203, and the determination unit 204, respectively.

[0012] The display device 101 is a portable terminal such as a smartphone or tablet terminal that can be easily carried by a user. The display unit 201 is a display configured with an LCD, OLED, or the like. The display control unit 202 controls the display of the display unit 201 based on signals acquired from the detection unit 203 and the determination unit 204, and corrects the position and shape of the code information displayed on the display unit 201. The detection unit 203 can detect changes in the relative position between the display unit 201 and the reading unit 205 of the reading device 102.

[0013] The detection unit 203 includes an acceleration sensor and an angular velocity sensor (not shown), and uses these to detect translational and rotational movement of the display unit 201. For example, the detection unit 203 detects a change in the relative position between the display unit 201 and the reading unit 205 of the reading device 102 based on the detection result and the detection result of translational and rotational movement of the reading unit 205 of the reading device 102 detected by the detection unit 206 of the reading device 102. Note that the method of detecting a change in the relative position between the display unit 201 and the reading unit 205 of the reading device 102 is not limited to this method. For example, the display device 101 may include a camera, which captures an image of the reading device 102, and the change in the relative position between the display unit 201 and the reading unit 205 of the reading device 102 may be detected from a change in the captured image of the reading device 102.

[0014] The determination unit 204 determines the shake correction performance of the reading device 102. For example, the determination unit 204 determines, as the shake correction performance, which of the three axes (X, Y, Z) along which the reading device 102 can translate and the three axes (Pitch, Yaw, Roll) along which the reading device 102 can rotate, the reading device 102 has a correction function for. Each axis is illustrated in FIG. 1. In this embodiment, in addition to the above, the determination unit 204 may also determine, as the shake correction performance, the amount of correction possible for each axis and the frequency response of correction. The determination unit 204 determines the shake correction performance of the reading device 102 based on information acquired from the reading device 102 via communication means (not shown). Alternatively, the determination unit 204 determines the shake correction performance of the reading device 102 based on information about the reading device 102 that was previously stored in the display device 101.

[0015] The reading device 102 includes a reading unit 205, a detection unit 206, a correction unit 207, and a reading control unit 208. The reading unit 205 is connected to the correction unit 207 and the reading control unit 208. The detection unit 206 is connected to the correction unit 207.

[0016] The reading unit 205 includes a camera (not shown). This camera is composed of an image sensor (not shown) such as a CCD or CMOS, and an optical system (not shown) that forms an image of a subject on the image sensor. The reading unit 205 converts the image of the subject formed on the image sensor into an image and outputs the image to the reading control unit 208 at predetermined imaging intervals.

[0017] The detection unit 206 is capable of detecting a change in the relative position between the reading unit 205 and the subject. The detection unit 206 includes an acceleration sensor and an angular velocity sensor, and uses these to detect a change in the relative position between the reading unit 205 and the subject. Note that the method for detecting a change in the relative position between the reading unit 205 and the subject is not limited to this method, and a change in the relative position between the reading unit 205 and the subject may be detected from a change in the image of the subject captured by the reading unit 205.

[0018] The correction unit 207 corrects the subject image obtained by the reading unit 205 based on the change in the relative position between the reading unit 205 and the subject detected by the detection unit 206, and is able to reduce image blurring caused by the change in relative position. The correction unit 207 performs correction control by moving a part of the optical system to translate or rotate the optical axis of the optical system. Note that the method for correcting the subject image is not limited to this method, and for example, a configuration in which the subject image or the position or shape of the image is corrected by image transformation may also be used.

[0019] The reading control unit 208 recognizes code information from the image obtained by the reading unit 205 and converts the recognized code information back to the original information before it was converted into the code information. In this embodiment, the reading control unit 208 recognizes code information from the subject image corrected by the correction unit 207, thereby reducing the influence of changes in the relative positions of the display unit 201 on which the code information is displayed and the reading unit 205, and improving the accuracy with which the reading device 102 reads the code information.

[0020] Fig. 3 is a flowchart showing the procedure of the display control process executed by the display control unit 202 in Fig. 2. The relative positions of the display unit 201 and the reading unit 205 change along a total of six axes, including three axes (X, Y, Z) along which they can translate and three axes (Pitch, Yaw, Roll) along which they can rotate, and the display control by the display control unit 202 is also performed along each of the six axes. In the display control process in Fig. 3, display control along one of the six axes will be described as an example, but display control is also performed along the other axes in the same manner.

[0021] In FIG. 3, the display control unit 202 determines whether the reading device 102 has shake correction performance for the axis that is the target of display control, based on the result of the determination unit 204 determining the shake correction performance of the reading device 102 (step 301).

[0022] If it is determined in step S301 that the reading device 102 does not have shake correction performance for the axis that is the target of display control, the display control unit 202 acquires relative position change information from the detection unit 203 (step S302). The relative position change information is information that indicates a change in the relative position between the display unit 201 and the reading unit 205 detected by the detection unit 203. Next, the display control unit 202 corrects the display position and shape of the code information based on the acquired relative position change information, and displays the code information whose display position and shape have been corrected on the display unit 201 (step S303). The correction of the code information will be described later. Next, the display control unit 202 determines whether the reading device 102 has completed reading the code information (step S304).

[0023] If it is determined in step S304 that the reading device 102 has not completed reading the code information, the display control process returns to step S302. If it is determined in step S304 that the reading device 102 has completed reading the code information, the display control process ends.

[0024] If it is determined in step S301 that the reading device 102 has shake correction performance for the axis that is the target of display control, the display control unit 202 displays the code information on the display unit 201 without correcting the display position and shape of the code information (step S305). Next, the display control unit 202 determines whether the reading device 102 has completed reading the code information (step S306).

[0025] If it is determined in step S306 that the reading device 102 has not completed reading the code information, the display control process returns to step S305. If it is determined in step S306 that the reading device 102 has completed reading the code information, the display control process ends.

[0026] In this embodiment, the above-mentioned processing is performed for each of the six axes, and control is performed so that control to correct the display position and shape of the code information by the display device 101 is not performed for each axis in addition to the correction by the correction unit 207 of the reading device 102.

[0027] Fig. 4 is a diagram for explaining the correction of code information in step S303 in Fig. 3. In Fig. 4, area A is the display range of display unit 201. Area B is the readable range of reading unit 205. Area C is the area corresponding to the code information. Dotted lines indicate each area before the relative positions of display unit 201 and reading unit 205 change.

[0028] For example, when the relative position between the display unit 201 and the reading unit 205 changes in the X and Y directions or the Pitch and Yaw directions, at least one of a parallel translation of region B and a trapezoidal deformation of region B occurs depending on the positional relationship between the two. For example, when a parallel translation of region B occurs as shown in FIG. 4(a), the display control unit 202 corrects the code information so as to translate region C as shown by the solid line in FIG. 4(a) based on the relative position change information acquired from the detection unit 203. When a trapezoidal deformation of region B occurs as shown in FIG. 4(b), the display control unit 202 corrects the code information so as to translate region C as shown by the solid line in FIG. 4(b) based on the relative position change information acquired from the detection unit 203.

[0029] When the relative position between the display unit 201 and the reading unit 205 changes in the Z direction, the area B expands or contracts. For example, when the area B contracts as shown in Fig. 4(c), the display control unit 202 corrects the code information based on the relative position change information acquired from the detection unit 203 so as to contract the area C as shown by the solid line in Fig. 4(c).

[0030] When the relative position between the display unit 201 and the reading unit 205 changes in the Roll direction, the area B rotates. For example, when the area B rotates as shown in Fig. 4(d), the display control unit 202 corrects the code information based on the relative position change information acquired from the detection unit 203 so as to rotate the area C as shown by the solid line in Fig. 4(d).

[0031] According to the above-described embodiment, it is determined whether to perform a predetermined display control to improve the accuracy of reading code information by the reading device 102 when the relative position with respect to the reading device 102 changes, based on the result of the determination regarding the function of the reading device 102. This makes it possible to perform control to improve the accuracy of reading code information by the reading device 102 in accordance with the function of the reading device 102, thereby improving the accuracy of reading code information by the reading device 102 when the relative position with respect to the reading device 102 changes.

[0032] Furthermore, in the above-described embodiment, if the reading device 102 does not have shake correction capability, correction display control is performed to correct the display position and shape of the code information, and if the reading device 102 has shake correction capability, correction display control is not performed. This makes it possible to prevent the reading unit 205 of the reading device 102 from being unable to properly read the code information when the reading device 102 has shake correction capability, due to the correction display control being performed in addition to the correction by the correction unit 207 of the reading device 102.

[0033] Furthermore, in the above-described embodiment, it is determined which of the three axes along which the reading device 102 can move in parallel and the three axes along which the reading device 102 can move in rotation has the shake correction performance. This makes it possible to control the above-described correction display control so that it does not overlap with the correction by the correction unit 207 of the reading device 102 for each axis.

[0034] In the above-described embodiment, the display device 101 is a portable terminal that can be easily carried by a user. This can improve the accuracy of reading code information by the reader 102 in a situation where the relative position of the display device 101 to the reader 102 is likely to change due to the user holding the display device 101 in his / her hand.

[0035] Next, a display device and a control method thereof according to a second embodiment of the present invention will be described. The second embodiment is basically the same as the first embodiment in terms of configuration and operation, but differs from the first embodiment in that the brightness and display timing of code information are corrected. Therefore, a description of the overlapping configuration and operation will be omitted, and the following description will focus on the different configuration and operation.

[0036] 5 is a block diagram schematically illustrating a configuration of a display device 501 according to a second embodiment of the present invention. In FIG. 5, the display device 501 includes the display unit 201 and the detection unit 203 of FIG. 2, and further includes a display control unit 502 and a determination unit 503.

[0037] The display control unit 502 performs display control on the display unit 201 based on a signal acquired from the determination unit 503, and corrects the brightness and display timing of the code information displayed on the display unit 201. The determination unit 503 determines the image capture cycle of the reading device 102. As described above, in the reading device 102, the reading unit 205 converts the subject image formed on the image sensor into an image and outputs the image to the reading control unit 208 at each predetermined image capture cycle. For example, the determination unit 503 determines the image capture cycle of the reading device 102 based on information acquired from the reading device 102 via a communication means (not shown). Alternatively, the determination unit 503 determines the image capture cycle of the reading device 102 based on information about the reading device 102 that has been stored in advance in the display device 101.

[0038] FIG. 6 is a flowchart showing the procedure of the display control process executed by the display control unit 502 in FIG.

[0039] 6, first, the display control unit 502 acquires the image capturing cycle of the reading device 102 determined by the determination unit 503 from the determination unit 503, and determines whether the acquired image capturing cycle is greater than a preset threshold T1 (step S601). The threshold T1 is the longest image capturing time during which a change in the relative position between the subject and the reading device 102 due to, for example, camera shake or the like does not affect the image. In other words, if the image capturing cycle is greater than the threshold T1, a change in the relative position will affect the image.

[0040] In step S601, if the acquired imaging cycle is greater than the threshold value T1, the display control unit 502 performs predetermined brightness control based on the acquired imaging cycle and displays the code information on the display unit 201 (step S602). The predetermined brightness control will be described later. Next, the display control unit 502 determines whether the reading device 102 has completed reading the code information (step S603).

[0041] If it is determined in step S603 that the reading device 102 has not completed reading the code information, the display control process returns to step S602. If it is determined in step S603 that the reading device 102 has completed reading the code information, the display control process ends.

[0042] In step S601, if the acquired imaging period is equal to or less than the threshold value T1, the display control unit 502 displays the code information on the display unit 201 without performing predetermined brightness control (step S604). Next, the display control unit 502 determines whether the reading device 102 has completed reading the code information (step S605).

[0043] If it is determined in step S605 that the reading device 102 has not completed reading the code information, the display control process returns to step S604. If it is determined in step S605 that the reading device 102 has completed reading the code information, the display control process ends.

[0044] Fig. 7 is a diagram for explaining the brightness control of code information in step S602 in Fig. 6. In Fig. 7, IMG indicates the imaging sequence of the reading device 102. In the reading device 102, imaging is started at a fixed imaging cycle Tf, and imaging is performed successively as in imaging F1, F2, F3, .... For each imaging, the reading unit 205 converts the subject image into an image and outputs the image to the reading control unit 208, and the reading control unit 208 recognizes the code information from the acquired image.

[0045] DISP_A indicates display control of code information without the predetermined brightness control in step S604. In DISP_A, display Da is continuously performed at brightness Ba regardless of the imaging cycle Tf.

[0046] DISP_B indicates the display control of code information that performs predetermined brightness control in step S602. In DISP_B, brightness Bb is displayed for only a display time Td2 in a cycle Td1 that is the same as the imaging cycle Tf. That is, the display Db1, Db2, Db3, ... flashes in a cycle Td1. Brightness Bb is set to a brightness higher than brightness Ba so that the integrated light amount per imaging (see the gray area in FIG. 7) is the same as that of DISP_A. This does not affect the photometry or image brightness during imaging, and can prevent a decrease in reading accuracy. On the other hand, in DISP_B, the display time per imaging is shorter than DISP_A, so the impact of blurring, etc., on the image caused by changes in the relative position between the subject and the reading device 102 due to camera shake, etc., can be reduced.

[0047] In the above-described embodiment, when the imaging cycle of the reading device 102 is equal to or less than a threshold value, a first display control is performed in which the code information is continuously displayed on the display unit 201 at a luminance Ba. When the imaging cycle of the reading device 102 is greater than the threshold value, a second display control is performed in which the code information is flashing on the display unit 201 at a luminance Bb higher than the luminance Ba, with a cycle Td1 that is the same as the imaging cycle Tf. This makes it possible to reduce the influence of blurring and the like on an image caused by a change in the relative position between the subject and the reading device 102 due to hand shake or the like when the imaging cycle of the reading device 102 is greater than the threshold value, thereby preventing a decrease in the reading accuracy of the reading device 102.

[0048] Furthermore, in the above-described embodiment, the integrated light amount per image capture based on the imaging cycle of the reading device 102 in the second display control is the same as the integrated light amount per image capture based on the imaging cycle of the reading device 102 in the first display control. This makes it possible to reduce the impact of blurring and other such changes in the relative positions of the subject and the reading device 102 due to camera shake or the like on the image, without affecting the photometry during imaging or the brightness of the image.

[0049] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions. [Explanation of symbols]

[0050] 101 Display device 102 Reading device 201 Display section 202 Display control unit 204 Judgment section

Claims

1. A display means; a display control means for controlling the display means to display code information; a determination means for determining a function of a reading device that reads the code information, The display device is characterized in that the display control means determines, based on the result of the judgment by the judgment means, whether to perform a predetermined display control that improves the reading accuracy of the code information by the reading device when the relative position with respect to the reading device changes.

2. the determining means determines whether the reading device has a shake correction function; The display device according to claim 1, characterized in that the display control means performs correction display control to correct the display position and shape of the code information when the reading device does not have shake correction capability, and does not perform the correction display control when the reading device has shake correction capability.

3. 3. The display device according to claim 2, wherein the determining means determines whether the reading device has shake correction capability for three axes along which the reading device can translate and three axes along which the reading device can rotate.

4. the determining means determines whether or not an image capturing period of the reading device is greater than a preset threshold value; 2. The display device according to claim 1, wherein the display control means performs first display control to continuously display the code information on the display means at a first brightness when the imaging cycle of the reading device is equal to or less than the threshold value, and performs second display control to flash the code information on the display means at a second brightness higher than the first brightness during the imaging cycle when the imaging cycle of the reading device is greater than the threshold value.

5. The display device according to claim 4, characterized in that the integrated light amount per image captured based on the imaging cycle of the reading device in the second display control is the same as the integrated light amount per image captured based on the imaging cycle of the reading device in the first display control.

6. 6. The display device according to claim 1, wherein the display device is a mobile terminal.

7. A method for controlling a display device having a display means, comprising: a display control step of controlling the display means to display code information; a determination step of determining a function of a reading device that reads the code information, The display control step determines, based on the result of the judgment in the judgment step, whether or not to perform a predetermined display control that improves the accuracy of reading the code information by the reading device when the relative position with respect to the reading device changes.

8. 7. A program for causing a computer to execute each means of the display device according to claim 1.

Images