Patent Publication Number: US-2021192481-A1

Title: Information processing device and method

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2019-232477, filed in Dec. 24, 2019, the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments described herein relate generally to an information processing device and a method. 
     BACKGROUND 
     In the related art, commodity sales data processing devices such as POS terminals (Point of Sales) have been used in stores such as supermarkets. The commodity sales data processing device maintains an environment where a stable operation is possible by maintenance work such as a data update performed by a maintenance person. For example, in the related art, a technique has been proposed in which a checklist is displayed on a display unit of a portable terminal carried by a maintenance person, and maintenance work can be performed while looking at the displayed checklist. 
     In the interim, since the above-mentioned maintenance work is performed by a manual operation of a maintenance person, there is a possibility that a work mistake such as a work omission or a work error may occur. For example, in the maintenance work in which the order of execution is determined, if the operation is performed while a work mistake occurs, a backtracking work occurs, and thus the work time and the number of work steps may increase. 
     In the method of the related art which uses a checklist, the work check is left to the maintenance person himself/herself. If the maintenance person makes a mistake in checking the work or does not check the work, there is a possibility to proceed with the work without noticing the work mistake, which leaves room for further improvement. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating an example of a maintenance system according to a first embodiment; 
         FIG. 2  is a diagram illustrating an example of a hardware configuration of a POS terminal according to the first embodiment; 
         FIG. 3  is a diagram illustrating an example of a hardware configuration of a server device according to the first embodiment; 
         FIG. 4  is a diagram illustrating an example of a hardware configuration of a maintenance terminal according to the first embodiment; 
         FIG. 5  is a diagram illustrating an example of a checklist according to the first embodiment; 
         FIG. 6  is a diagram illustrating an example of a functional configuration of the maintenance system according to the first embodiment; 
         FIG. 7  is a diagram illustrating an example of an execution status registered in the checklist according to the first embodiment; 
         FIG. 8  is a flowchart illustrating an example of a process executed by the POS terminal according to the first embodiment; 
         FIG. 9  is a flowchart illustrating an example of a process executed by the server device according to the first embodiment; 
         FIG. 10  is a flowchart illustrating an example of a process executed by the maintenance terminal according to the first embodiment; 
         FIG. 11  is a diagram illustrating an example of a maintenance system according to a second embodiment; 
         FIG. 12  is a diagram illustrating an example of a hardware configuration of a server device according to the second embodiment; 
         FIG. 13  is a diagram illustrating an example of a functional configuration of the server device according to the second embodiment; 
         FIG. 14  is a diagram illustrating an example of a checklist according to Modification 1; 
         FIG. 15  is a diagram illustrating an example of a checklist according to Modification 2; and 
         FIG. 16  is a diagram illustrating an example of a maintenance system according to Modification 3. 
     
    
    
     DETAILED DESCRIPTION 
     An aspect of the present disclosure is to provide an information processing device and a method that can improve the efficiency of maintenance work. 
     In general, according to one embodiment, an information processing device includes an acquisition means, a determination means, and an output means. The acquisition means acquires a work content related to a predetermined work item performed by the device to be maintained. The determination means determines whether or not the work content acquired by the acquisition means is appropriate based on a checklist that stores a work content serving as a reference for the work item. The output means outputs a determination result of the determination means. 
     Hereinafter, a maintenance system according to an embodiment will be described with reference to the drawings. A POS terminal used in a store will be described as a device to be maintained. The present disclosure is not limited by the embodiments described below. 
     First Embodiment 
       FIG. 1  is a diagram illustrating an example of a maintenance system according to the present embodiment. As shown in  FIG. 1 , a maintenance system  1  includes a POS terminal  10 , a server device  20 , and a maintenance terminal  30 . Further, the maintenance system  1  includes a lighting device  40 . 
     The POS terminal  10  and the server device  20  are connected via a network N 1  such as a local area network (LAN) provided in the store. The server device  20  and the lighting device  40  are connected via a cable N 2  such as a control line. That is, the POS terminal  10  and the lighting device  40  are connected via the server device  20 . The number of POS terminals  10  and the number of lighting devices  40  are not limited to the example of  FIG. 1 . 
     The POS terminal  10  is an example of a commodity sales data processing device that is provided in a checkout section in a store and performs a settlement process for a commodity purchased by a customer. In the present embodiment, the POS terminal  10  is a device to be maintained on which maintenance work such as data update is performed by a maintenance person. The POS terminal  10  is not limited to a normal POS terminal operated by a store clerk, but also includes a self-service type POS terminal operated by a customer. In addition, the POS terminal  10  includes a semi-self-service type POS terminal in which a clerk operates sales registration and a customer performs a checkout operation. 
     The POS terminal  10  includes a clerk display unit  110  including a backlight  1101  described below. The POS terminal  10  can perform visible light communication by modulating the intensity of light emitted from the backlight  1101 . In addition, the visible light communication can use a known and public technology. 
     The server device  20  is, for example, a store server placed in a store and receives various information transmitted from each of the POS terminals  10 . In addition, the server device  20  is connected to the lighting device  40  and controls the light emission of the lighting device  40 . 
     A plurality of lighting devices  40  are installed, for example, on the ceiling of the store and illuminate the entrance and exit of the store, display portions where commodities are displayed, the checkout section, and the like from above. The server device  20  can perform visible light communication by modulating the intensity of light emitted from the lighting device  40 . 
     In the present embodiment, a light source device such as light emitting diode (LED) lighting is used as a light source of the backlight  1101  and the lighting device  40  described later. In the LED lighting, the modulation frequency can be set high in particular. Therefore, by using LED lighting as the light source of the backlight  1101  and the lighting device  40 , the light intensity can be modulated in a high frequency band in which human eyes do not sense flickering. 
     The maintenance terminal  30  is an example of an information processing device. The maintenance terminal  30  is carried by a maintenance person and used when performing maintenance work on the POS terminal  10 . As the maintenance terminal  30 , for example, a portable terminal device such as a smartphone or a tablet terminal can be used. The maintenance terminal  30  can receive information transmitted by visible light communication by analyzing image data captured by an imaging unit  310  described below. 
     Next, the device configuration of the above-described maintenance system  1  will be described. 
     First, the hardware configuration of the POS terminal  10  will be described.  FIG. 2  is a diagram illustrating an example of the hardware configuration of the POS terminal  10 . As shown in  FIG. 2 , the POS terminal  10  includes a central processing unit (CPU)  101 , a read only memory (ROM)  102 , and a random access memory (RAM)  103 . 
     The CPU  101  is an example of a processor and controls the operation of the POS terminal  10  in an integrated manner. The ROM  102  stores various programs. The RAM  103  is a workspace for loading programs and various data. The CPU  101 , the ROM  102 , and the RAM  103  are connected to each other via a bus  104 . The CPU  101 , the ROM  102 , and the RAM  103  constitute a control unit  100  configuring a computer. In the control unit  100 , the CPU  101  executes various processes by operating in accordance with a program stored in the ROM  102  or a storage unit  105  described later and loaded in the RAM  103 . 
     The storage unit  105  is connected to the control unit  100  via the bus  104 . The storage unit  105  is a storage device such as a solid state drive (SSD), a hard disk drive (HDD), and a flash memory, and retains the stored contents even when the power is turned off. 
     The storage unit  105  stores, for example, various data such as a basic program  1051 , an application program  1052 , a commodity master  1053 , and the like. The basic program  1051  is a program for realizing the basic operation of the POS terminal  10 , such as an operating system. The application program  1052  is a program for realizing a predetermined function related to a commercial transaction (for example, a function related to a settlement process). The commodity master  1053  is a database or the like that stores information on commodities sold in the store. For example, the commodity master  1053  stores various commodity information such as a commodity name and a unit price in association with a commodity code for identifying each commodity. 
     Further, a communication unit  106  and a clock unit  107  are connected to the control unit  100  via the bus  104 . The communication unit  106  is a wired or wireless communication interface that can be connected to the network N 1 . The communication unit  106  communicates with the server device  20  and the like via the network N 1 . The clock unit  107  is a clock device such as a real time clock (RTC). The clock unit  107  measures, for example, the current date and time. 
     An operation unit  109 , the clerk display unit  110 , a customer display unit  111 , a printer  112 , a code reader  113 , and the like are connected to the control unit  100  via the bus  104  and an input and output controller  108 . 
     The operation unit  109  includes a keyboard including various operation buttons, a pointing device, and the like. The operation unit  109  receives an operation of the operator and outputs the content of the received operation to the control unit  100 . 
     The clerk display unit  110  is a display device such as a liquid crystal display (LCD) including the backlight  1101 . The backlight  1101  is configured by a light source device such as an LED as described above. The backlight  1101  can perform visible light communication by modulating light emitted by the light source device under the control of the control unit  100 . 
     In addition, the clerk display unit  110  displays various screens, such as a screen related to the operation of the POS terminal  10 , a screen related to the settlement process for a commodity, and a screen indicating the data update status, under the control of the control unit  100 . The operation unit  109  may be, for example, a touch panel provided on a surface of the clerk display unit  110 . 
     The customer display unit  111  is configured by a display device similar to the clerk display unit  110 , for example. Under the control of the control unit  100 , the customer display unit  111  displays a screen presented to the customer, such as a screen related to the settlement process for a commodity. 
     The printer  112  is, for example, a thermal printer including a thermal head. The printer  112  prints commodity information and information related to the settlement on long thermal paper to dispense a receipt. The code reader  113  is a reading device that reads a code symbol such as a bar code attached to a commodity. The code reader  113  receives an input of a commodity to be purchased by a customer by reading a commodity code held by the code symbol. 
     Next, a hardware configuration of the server device  20  will be described.  FIG. 3  is a diagram illustrating an example of a hardware configuration of the server device  20 . As shown in  FIG. 3 , the server device  20  includes a CPU  201 , a ROM  202 , and a RAM  203 . 
     The CPU  201  is an example of a processor and controls the operation of the server device  20  in an integrated manner. The ROM  202  stores various programs. The RAM  203  is a workspace for loading programs and various data. The CPU  201 , the ROM  202 , and the RAM  203  are connected to each other via a bus  204 . The CPU  201 , the ROM  202 , and the RAM  203  constitute a control unit  200  configuring a computer. In the control unit  200 , the CPU  201  executes various processes by operating in accordance with a program stored in the ROM  202  or a storage unit  205  described later and loaded in the RAM  203 . 
     The storage unit  205  and a communication unit  206  are connected to the control unit  200  via the bus  204 . The storage unit  205  is a storage device such as an SSD, an HDD, and a flash memory, and retains the stored contents even when the power is turned off. The storage unit  205  stores various programs executed by the CPU  201  and setting information. The communication unit  206  is a wired or wireless communication interface that can be connected to the network N 1 . The communication unit  206  communicates with the POS terminal  10  and the like via the network N 1 . 
     The lighting device  40  is connected to the control unit  200  via the bus  204  and an input and output controller  207 . The lighting device  40  includes a light source device such as an LED lighting as described above. The lighting device  40  can perform visible light communication by modulating light emitted from the light source device under the control of the control unit  200 . 
     Next, the hardware configuration of the maintenance terminal  30  will be described.  FIG. 4  is a diagram illustrating an example of a hardware configuration of the maintenance terminal  30 . As shown in  FIG. 4 , the maintenance terminal  30  includes a CPU  301 , a ROM  302 , and a RAM  303 . 
     The CPU  301  is an example of a processor and controls the operation of the maintenance terminal  30  in an integrated manner. The ROM  302  stores various programs. The RAM  303  is a workspace for loading programs and various data. The CPU  301 , the ROM  302 , and the RAM  303  are connected to each other via a bus  304 . The CPU  301 , the ROM  302 , and the RAM  303  constitute a control unit  300  configuring a computer. In the control unit  300 , the CPU  301  executes various processes by operating in accordance with a program stored in the ROM  302  or a storage unit  305  described below and loaded in the RAM  303 . 
     The storage unit  305  is connected to the control unit  300  via the bus  304 . The storage unit  305  includes an SSD, an HDD, a flash memory, and the like, and retains the stored contents even when the power is turned off. The storage unit  305  stores various programs executed by the CPU  301  and setting information. Further, the storage unit  305  stores a checklist CL 1  indicating a work procedure of a maintenance work performed by the maintenance person on the POS terminal  10 . 
       FIG. 5  is a diagram illustrating an example of the checklist CL 1 . As shown in  FIG. 5 , the checklist CL 1  stores work items, work contents, and execution statuses in association with each other. Here, an identification number is set in the work item to identify a series of work contents set in advance. In this embodiment, the work item also functions as a process number that defines the order in which each work is performed. In the work content, a work content as a reference to be performed by the maintenance person is set. In the execution status, information indicating the execution status of each work is input in the processing described below. In the execution status, for example, information such as “unexecuted” indicating that the work is not performed, “completed” indicating that the work was completed, and “work in progress” indicating that the work is being performed is input. In the initial state of the checklist CL 1  before the start of the work, it is assumed that the execution status of any work item is set to “unexecuted”. 
     For example, the maintenance person using the maintenance terminal  30  displays the above-described checklist CL 1  on a display unit  309  described later and performs the maintenance work on the POS terminal  10  while checking the work content of each work item registered in the checklist CL 1 . In this case, the checklist CL 1  may be displayed by a manual operation of a maintenance person via an operation unit  308  described later or may be automatically displayed under the control of an output unit  353  described later. 
     The hardware configuration of the maintenance terminal  30  is not limited to the example of  FIG. 4 . For example, the maintenance terminal  30  may include a communication device that can be connected to the network N 1 , a communication device that can be connected to a public line network, and the like. 
     Returning to  FIG. 4 , a clock unit  306  is connected to the control unit  300  via the bus  304 . The clock unit  306  is a clock device such as an RTC. The clock unit  306  measures, for example, the current date and time. 
     Further, the operation unit  308 , the display unit  309 , the imaging unit  310 , and the like are connected to the control unit  300  via the bus  304  and an input and output controller  307 . 
     The operation unit  308  includes various operation buttons and outputs key information corresponding to the operation of the operator to the control unit  300 . The display unit  309  is a display device such as an LCD. The display unit  309  displays various screens under the control of the control unit  300 . The operation unit  308  may be, for example, a touch panel provided on the surface of the display unit  309 . 
     The imaging unit  310  is an imaging device including an image sensor such as a charge coupled device (CCD) or a complementary MOS (CMOS). The imaging unit  311  outputs image data obtained by imaging to the control unit  300 . 
     In the present embodiment, the imaging unit  311  captures a moving image as image data. The imaging unit  311  is used to receive light emitted by the clerk display unit  110  (backlight  1101 ) and the lighting device  40 . A configuration may be adopted in which a light receiving device for visible light communication is provided instead of the imaging unit  311 . 
     Next, a functional configuration of the maintenance system  1  will be described.  FIG. 6  is a diagram illustrating an example of a functional configuration of the maintenance system  1 . 
     As shown in  FIG. 6 , the POS terminal  10  includes a work content acquisition unit  151 , a transmission unit  152 , a first modulation unit  153 , and a first light source control unit  154  as functional units. These functional units are activated when the POS terminal  10  is shifted to a maintenance mode for maintenance work by a predetermined operation via the operation unit  109 , for example. 
     Some or all of the above-described functional units may have a software configuration realized by cooperation between a processor (for example, CPU  101 ) of the POS terminal  10  and a program stored in a memory (for example, ROM  102 , storage unit  105 ). For example, some or all of the functional units described above may be implemented by the basic program  1051 , the application program  1052  for the maintenance and inspection work, and the like. Further, some or all of the functional units described above may have a hardware configuration realized by a dedicated circuit or the like mounted on the POS terminal  10 . 
     The work content acquisition unit  151  acquires the content of the maintenance work performed on the own device by the maintenance person as the work content. Specifically, in response to an operation via the operation unit  109  or the like, the work content acquisition unit  151  acquires the content of the operation, the content of a process executed in response to the operation, and the like as the work content. For example, the work content acquisition unit  151  acquires the work content at the start and end of the process. The work content is not limited to the above and may include other information. For example, the time at which the process started or the time at which the process ended may be acquired as the work content. 
     The transmission unit  152  transmits the work content acquired by the work content acquisition unit  151  to the server device  20 . As will be described later, the work content transmitted to the server device  20  is transmitted by visible light communication via the lighting device  40  under the control of the server device  20 . 
     The first modulation unit  153  generates a control signal for transmitting the work content acquired by the work content acquisition unit  151  by visible light communication. Specifically, the first modulation unit  153  superimposes information indicating the work content acquired by the work content acquisition unit  151  on a control signal for controlling the light emission of the backlight  1101 , thereby generating a control signal for the visible light communication. 
     The first light source control unit  154  controls the light emission of the backlight  1101  based on the control signal generated by the first modulation unit  153 . The first light source control unit  154  controls the light emission of the backlight  1101 , thereby transmitting the work content acquired by the work content acquisition unit  151  by visible light communication. 
     The server device  20  includes a receiving unit  251 , a second modulation unit  252 , and a second light source control unit  253  as functional units. 
     Some or all of the functional units described above may have a software configuration realized by cooperation between a processor (for example, CPU  201 ) of the server device  20  and a program stored in a memory (for example, ROM  202 , storage unit  205 ). In addition, some or all of the functional units described above may have a hardware configuration realized by a dedicated circuit or the like mounted on the server device  20 . 
     The receiving unit  251  receives information transmitted from the POS terminal  10 . Specifically, the receiving unit  251  receives the work content transmitted from the transmission unit  152  of the POS terminal  10 . 
     The second modulation unit  252  generates a control signal for transmitting the work content received by the receiving unit  251  by visible light communication. Specifically, the second modulation unit  252  superimposes information indicating the work content received by the receiving unit  251  on a control signal for controlling the light emission of the lighting device  40 , thereby generating a control signal for the visible light communication. 
     The second light source control unit  253  controls the light emission of the lighting device  40  based on the control signal generated by the second modulation unit  252 . The second light source control unit  253  controls the light emission of the lighting device  40  to transmit the end time received by the receiving unit  251 , that is, the work content related to the maintenance work performed by the POS terminal  10  by visible light communication. 
     The maintenance terminal  30  includes a receiving unit  351 , a determination unit  352 , and an output unit  353  as functional units. 
     Some or all of the functional units described above may have a software configuration realized by cooperation between a processor (for example, CPU  301 ) of the maintenance terminal  30  and a program stored in a memory (for example, ROM  302 , storage unit  305 ). Further, some or all of the functional units described above may have a hardware configuration realized by a dedicated circuit or the like mounted on the maintenance terminal  30 . 
     The receiving unit  351  is an example of an acquisition unit. The receiving unit  351  receives the information transmitted by visible light communication by analyzing the image data captured by the imaging unit  311 . Specifically, the receiving unit  351  acquires information superimposed on the light by analyzing the intensity of the light received by the imaging unit  311 . 
     For example, when the clerk display unit  110  is imaged by the imaging unit  311 , the receiving unit  351  analyzes the intensity of light emitted from the backlight  1101  captured in a moving image, thereby acquiring the work content superimposed on the light. In addition, for example, when the lighting device  40  is imaged by the imaging unit  311 , the receiving unit  351  analyzes the intensity of light emitted from the lighting device  40  captured in a moving image, thereby acquiring the work content superimposed on the light. 
     The determination unit  352  is an example of a determination unit. The determination unit  352  determines whether or not the work content received by the receiving unit  351  is appropriate based on the checklist CL 1  stored in the storage unit  305 . 
     Specifically, the determination unit  352  compares each of the work contents registered in the checklist CL 1  with the work content received by the receiving unit  351  to determine whether or not the work content being performed on the POS terminal  10  matches the work content of the list CL 1 . When the work content received by the receiving unit  351  matches the work content of the checklist CL 1 , the determination unit  352  determines that the work content is appropriate and registers the current work status in the execution status column associated with the work content of the corresponding checklist CL 1 . 
     For example, when the work content received by the receiving unit  351  indicates the start of the work content “work content  001 ” of the work item “ 001 ” illustrated in  FIG. 5 , the determination unit  352  changes the execution status “unexecuted” of this work item to “work in progress”. For example, when the work content received by the receiving unit  351  indicates the end of the work content “work content  001 ” of the work item “ 001 ” illustrated in  FIG. 5 , the determination unit  352  changes the execution status “work in progress” of this work item to “completed”. 
     When the work content received by the receiving unit  351  indicates a work content other than the work contents registered in the checklist CL 1 , the determination unit  352  may exclude the other work content from the determination target or may determine to be inappropriate. In the latter case, for example, when the other work content indicates a predetermined work content (for example, a work having a possibility of data loss), it may be determined to be inappropriate. 
     Meanwhile, when the work is performed in the order of the work items registered in the checklist CL 1 , the execution status is sequentially changed to “completed” in the order of the work item numbers. However, if a work mistake such as a work omission or a work error occurs, the work item of the next stage is changed to “work in progress” or “completed” while the execution status of the previous stage is “unexecuted” or “work in progress”. 
     For example, the checklist CL 1  in  FIG. 7  shows an example in which the work item “ 076 ” is performed first without performing the work item “ 075 ”. As described above, when a work mistake such as a work omission or a work error occurs, the work item with the next stage number is “work in progress” (or “completed) while the work item with the preceding number is “unexecuted”.  FIG. 7  is a diagram illustrating an example of the execution status registered in the checklist CL 1 . 
     Therefore, the determination unit  352  determines whether or not the work is performed in the order of the work items by checking the execution status registered in the work status column of each work item. Specifically, when the work item of the preceding number is “completed” and the work item of the subsequent number is changed to “work in progress” or “completed”, the determination unit  352  determines that the work is performed in the order of the work items and determines to be appropriate. In addition, when the work item of the subsequent number is changed to “work in progress” or “completed” while the work item of the preceding number is “unexecuted”, the determination unit  352  determines that the work is not performed in the order of the work items and determines to be inappropriate. For example, in the example of  FIG. 7 , the determination unit  352  determines to be appropriate since the work item “ 076 ” is performed before the work item “ 075 ”, and determines that the work item “ 075 ” is skipped. 
     The output unit  353  is an example of an output unit. The output unit  353  outputs the determination result of the determination unit  352 . Specifically, the output unit  353  causes the display unit  309  to display and output the checklist CL 1  in which the execution status is registered by the determination unit  352 . In addition, when the determination unit  352  determines to be inappropriate, the output unit  353  causes the display unit  309  to display and output a screen notifying the fact. 
     For example, when the determination unit  352  determines that the work content other than the work contents registered in the checklist CL 1  is inappropriate, the output unit  353  displays a screen for instructing suspension of the work. Further, for example, when the determination unit  352  determines that a specific work item is skipped, the output unit  353  displays a screen to notify that a work mistake such as a work omission or a work error occurred for the work content of the specific work number. 
     The device to which the output unit  353  outputs data is not limited to the display unit  309 . For example, when a printer device is connected to the maintenance terminal  30 , the printer device may be used as an output destination. 
     As described above, in the maintenance system  1 , when the maintenance work is started by the POS terminal  10  by the maintenance person, the POS terminal  10  transmits the work content by visible light communication through the clerk display unit  110  and the lighting device  40 . Therefore, the maintenance person can input the work content being performed on the POS terminal  10  to the maintenance terminal  30  by pointing the imaging unit  311  of the maintenance terminal  30  carried by the maintenance person to the clerk display unit  110  or the lighting device  40 . 
     As a result, in the maintenance system  1 , even in an environment where the maintenance terminal  30  cannot be connected to the network N 1  or the POS terminal  10  due to, for example, security reasons, the work content being performed on the POS terminal  10  can be transmitted to the maintenance terminal  30 . 
     Further, the maintenance terminal  30  compares the work content received by the visible light communication with the checklist CL 1  to determine whether or not the work content being performed by the POS terminal  10  is appropriate. Then, the maintenance terminal  30  notifies the maintenance person of information by displaying the determination result on the display unit  309 . 
     Thereby, the maintenance person can easily confirm via the maintenance terminal  30  whether or not the maintenance work being performed on the POS terminal  10  is being performed in accordance with the regular procedure registered in the checklist CL 1 . Therefore, the maintenance person can proceed the work while checking whether or not the maintenance work performed by the maintenance person is appropriate for each work item. Thus, even if a work mistake such as a work omission or a work error occurs, the maintenance person can quickly respond. In addition, even when a backtracking work occurs due to a work mistake, the work time and the number of work steps required for the backtracking work can be reduced, so that the efficiency of the maintenance work can be improved. 
     Hereinafter, an operation example of the above-described maintenance system  1  will be described. 
     First, an operation example of the POS terminal  10  will be described with reference to  FIG. 8 .  FIG. 8  is a flowchart illustrating an example of a process executed by the POS terminal  10 . It is assumed that this process is executed while the maintenance work on the POS terminal  10  is being performed. 
     First, the work content acquisition unit  151  waits until an operation on the own device is received (ACT  11 ; No). Upon receiving the operation via the operation unit  109  (ACT  11 ; Yes), the work content acquisition unit  151  acquires the content of the operation and the content of the process accompanying the operation as the work content (ACT  12 ). 
     Subsequently, the transmission unit  152  transmits the work content acquired in ACT  12  to the server device  20  to transmit the work content being performed on the own device through visible light communication via the lighting device  40  (ACT  13 ). 
     Subsequently, the first modulation unit  153  generates a control signal on which the work content acquired in ACT  12  is superimposed (ACT  14 ). Next, the first light source control unit  154  controls the light emission of the backlight  1101  based on the control signal generated in ACT  14  (ACT  15 ), thereby transmitting the work content being performed on the own device by visible light communication using the backlight  1101  (ACT  16 ). Then, the first light source control unit  154  returns the process to ACT  11 . 
     Accordingly, the maintenance terminal  30  can receive the work content being performed on the POS terminal  10  by visible light communication by imaging the clerk display unit  110  with the imaging unit  310 . 
     Next, an operation example of the server device  20  will be described with reference to  FIG. 9 .  FIG. 9  is a flowchart illustrating an example of a process performed by the server device  20 . 
     First, the receiving unit  251  waits until the work content is transmitted from the POS terminal  10  (ACT  21 ; No). Upon receiving the work content from the POS terminal  10  (ACT  21 ; Yes), the receiving unit  251  causes the process to proceed to ACT  22 . 
     Subsequently, the second modulation unit  252  generates a control signal for visible light communication on which the work content received in ACT  21  is superimposed (ACT  22 ). Next, the second light source control unit  253  controls the light emission of the lighting device  40  based on the control signal generated in ACT  22  (ACT  23 ), thereby transmitting the work content by visible light communication using the lighting device  40  (ACT  24 ). Then, the second light source control unit  253  returns the process to ACT  21 . 
     Thereby, the maintenance terminal  30  can receive the work content being performed on the POS terminal  10  by visible light communication by imaging the lighting device  40  with the imaging unit  310 . 
     Next, an operation example of the maintenance terminal  30  will be described with reference to  FIG. 10 .  FIG. 10  is a flowchart illustrating an example of a process executed by the maintenance terminal  30 . It is assumed that the checklist CL 1  is displayed on the display unit  309  as a premise of this process. 
     First, the receiving unit  351  monitors the image data captured by the imaging unit  311  and waits until receiving the work content transmitted by visible light communication (ACT  31 ). When the work content is received (ACT  31 ; Yes), the determination unit  352  compares the received work content with each of the work contents registered in the checklist CL 1  (ACT  32 ), and determines whether or not there is a matching work content (ACT  33 ). 
     If there is no matching work content (ACT  33 ; No), the determination unit  352  determines that the work is inappropriate, displays a screen notifying that unnecessary work is being performed (ACT  34 ), and ends this process. 
     When it is determined that there is a matching work content (ACT  33 ; Yes), the determination unit  352  registers the current execution status in the execution status column of the matched work content (ACT  35 ). The output unit  353  displays the execution status registered in ACT  35  in the corresponding execution status column of the checklist CL 1  displayed on the display unit  309 . 
     Subsequently, the determination unit  352  determines whether or not the maintenance work is being performed in the order of the work items based on the execution status registered in the execution status column of each work item (ACT  36 ). Here, if the work is not performed in the order of the work items (ACT  36 ; No), the determination unit  352  determines that the work is inappropriate, displays a screen for notifying that a work mistake such as a work omission or a work error occurred (ACT  37 ), and ends this process. 
     On the other hand, when it is determined in ACT  36  that the maintenance work is performed in the order of the work items (ACT  36 ; Yes), the determination unit  352  determines whether or not the last work item registered in the checklist CL 1  was performed (ACT  38 ). When there is an unexecuted work item (ACT  38 ; No), the determination unit  352  returns the process to ACT  31 . When the last work item was completed (ACT  38 ; Yes), the determination unit  352  ends the process. 
     As described above, in the maintenance system  1 , when the maintenance work on the POS terminal  10  is started by the maintenance person, the work contents being performed on the POS terminal  10  are transmitted by the visible light communication via the clerk display unit  110  and the lighting device  40 . Further, in the maintenance system  1 , when the work content transmitted by the visible light communication is received by the maintenance terminal  30 , the work content is compared with the checklist CL 1 , and the maintenance terminal  30  displays a screen indicating whether or not the work content is appropriate. 
     According to the maintenance system  1  described above, it is possible to notify the maintenance person having the maintenance terminal  30  whether or not the work content being performed on the POS terminal  10  is appropriate. Accordingly, the maintenance system  1  can notify in real time whether or not the work content performed by the maintenance person is appropriate. Therefore, even if a work mistake such as a work omission or a work error occurs, the maintenance system  1  can quickly respond. In addition, the maintenance system  1  can thereby reduce the work time and the number of work steps required for a backtracking work even when the backtracking work occurs due to the occurrence of a work mistake. Therefore, the efficiency of the maintenance work can be improved. 
     In addition, according to the maintenance system  1 , by performing visible light communication using the backlight  1101  or the lighting device  40 , the work content being performed on the POS terminal  10  can be transmitted to the maintenance terminal  30  without connecting the maintenance terminal  30  to the network N 1 . Thus, even in an environment where the maintenance terminal  30  cannot be connected to the network N 1  or the POS terminal  10 , the work content performed on the POS terminal  10  can be transmitted to the maintenance terminal  30 . Therefore, the maintenance person can acquire the work content performed on the POS terminal  10  by the maintenance terminal  30  by imaging the clerk display unit  110  and the lighting device  40  without performing a procedure related to the communication with the POS terminal  10 . Therefore, the efficiency of maintenance work can be improved. 
     Second Embodiment 
     Next, a second embodiment will be described. In the first embodiment described above, the case where the POS terminal  10  transmits the work content to the server device  20  via the network N 1  is described. However, the method of transmitting the work content to the server device  20  is not limited thereto. 
     Therefore, in the present embodiment, a case where the end time information can be transmitted to the server device  20  using visible light communication will be described. The same components as those of the first embodiment are denoted by the same reference numerals and the description thereof is omitted. 
       FIG. 11  is a diagram illustrating an example of a maintenance system according to the present embodiment. As shown in  FIG. 11 , the maintenance system  2  includes the POS terminal  10 , a server device  50 , the maintenance terminal  30 , and the lighting device  40 . Further, the maintenance system  2  includes an imaging device  60 . Here, the server device  50  and the lighting device  40  are connected via the cable N 2  such as a control line. The server device  50  and the imaging device  60  are connected via a cable N 3  such as a data transmission line. In the present embodiment, it is assumed that the server device  50  is disconnected from the network N 1 . 
     The imaging device  60  is an imaging device including an image sensor such as a CCD or a CMOS. The imaging device  60  is, for example, a monitoring camera or the like installed on the ceiling or the like in an area where the POS terminal  10  is provided, and can image at least the clerk display unit  110  provided in the POS terminal  10 . 
     In the present embodiment, the imaging device  60  captures a moving image as image data. The imaging device  60  is used for receiving light emitted by the clerk display unit  110  (backlight  1101 ). Instead of the imaging device  60 , a light receiving device for visible light communication may be included. 
     The server device  50  is a device corresponding to the server device  20  of the first embodiment described above. The server device  50  has, for example, a hardware configuration illustrated in  FIG. 12 . Here,  FIG. 12  is a diagram illustrating an example of a hardware configuration of the server device  50 . 
     As shown in  FIG. 12 , the server device  50  includes the control unit  200  having a computer configuration such as the CPU  201 , the ROM  202 , and the RAM  203 . Further, the storage unit  205  and the communication unit  206  are connected to the control unit  200  via the bus  204 . The lighting device  40  and the imaging device  60  are connected to the control unit  200  via the bus  204  and the input and output controller  207  and the like. Image data captured by the imaging device  60  is input to the control unit  200 . 
     The server device  50  has, for example, a functional configuration illustrated in  FIG. 13 . Here,  FIG. 13  is a diagram illustrating an example of a functional configuration of the server device  50 . 
     As illustrated in  FIG. 13 , the server device  50  includes a receiving unit  551 , the second modulation unit  252 , and the second light source control unit  253  as functional units. 
     Here, the receiving unit  551  is a functional unit replacing the receiving unit  251  described above. The receiving unit  551  receives information transmitted by visible light communication by analyzing the image data captured by the imaging device  60 . Specifically, the receiving unit  551  receives the information superimposed on the light by analyzing the intensity (vibration) of the light received by the imaging device  60 . 
     For example, the receiving unit  551  receives the work content superimposed on the light by analyzing the intensity of light emitted from the backlight  1101  of the clerk display unit  110  from the image data of the clerk display unit  110  captured by the imaging device  60 . That is, the POS terminal  10  and the server device  50  of this embodiment exchange the work content by visible light communication. 
     The second modulation unit  252  performs the same operation as that of the above-described first embodiment based on the end time received by the receiving unit  551 . Thus, the server device  50  can transmit the end time of the update processing being executed on the POS terminal  10  to the maintenance terminal  30  by visible light communication via the lighting device  40 , similarly to the server device  20 . 
     Next, an operation example of the server device  50  will be described with reference to the above-described flowchart of  FIG. 9 . 
     First, the receiving unit  551  monitors the image data captured by the imaging device  60  and waits until a work content is transmitted by visible light communication (ACT  21 ; No). Upon receiving the end time from the imaging result of the imaging device  60  (ACT  21 ; Yes), the receiving unit  551  shifts the process to ACT  22 . Subsequent processes in ACT  22  to ACT  24  are the same as those in  FIG. 9 . 
     As described above, according to the present embodiment, the end time information can be transmitted from the POS terminal  10  to the server device  50  using visible light communication. Thus, for example, even when the POS terminal  10  operates in a stand-alone manner in accordance with the updating processing, it is possible to notify the server device  50  of the end time information. Thus, the same effect as in the above-described embodiment can be obtained. 
     Further, when the configuration of the present embodiment is adopted, the transmission unit  152  of the POS terminal  10  becomes unnecessary, and thus, the transmission unit  153  may be made invalid or removed from the POS terminal  10 . 
     The above-described embodiments (first and second embodiments) can be appropriately modified and implemented by partially changing the configuration or function of each device described above. Therefore, hereinafter, some modifications related to the above-described embodiments will be described as other embodiments. In the following, points different from the above-described embodiments will be mainly described, and the detailed descriptions of points common to the already described contents will be omitted. Further, the modifications described below may be implemented individually or may be implemented in combination as appropriate. 
     (Modification 1) 
     In the above-described embodiment, the work content being performed on the POS terminal  10  is compared with the work contents registered in the checklist CL 1  to determine whether or not the work content is appropriate. However, the determination result may be recorded as a history and used when performing the same maintenance work. 
     For example, as in a checklist CL 2  shown in  FIG. 14 , flag information may be set as a target of an attention notice for a work item determined to be inappropriate in the maintenance work performed in the past. Here, the history of the work mistake may be the history of the maintenance person using the maintenance terminal  30 , or may be the history of an unspecified large number of maintenance persons.  FIG. 14  is a diagram illustrating an example of the checklist CL 2 . 
     When the checklist CL 2  is used, the output unit  353  outputs information for notifying a work item for which flag information is set in the attention notice (hereinafter, also referred to as an attention target item) to the display unit  309  prior to the execution of the work item, thereby prompting the attention of the maintenance person. Specifically, the output unit  353  causes the display unit  309  to display a screen for prompting the attention to an attention target item at the timing when the execution status indicating that the work is completed in the work item immediately before the work item for which the flag information is set in the attention notice (hereinafter, also referred to as the attention target item). For example, the output unit  353  causes the display unit  309  to display a screen describing in detail the work content of the attention target item. 
     Thus, the maintenance person using the maintenance terminal  30  can easily confirm the work item in which a work mistake occurred in the past by looking at the display unit  309 . Therefore, in the present modification, among the works performed by the maintenance person on the POS terminal  10 , the work of the attention target item can be performed more carefully, so that a work mistake can be suppressed. 
     (Modification 2) 
     In the above-described embodiment, the work content being performed on the POS terminal  10  is compared with the work contents registered in the checklist CL 1  to determine whether or not the work content is appropriate. However, the suitability may be determined for other matters related to the maintenance work. For example, the determination unit  352  acquires the time required for the work by the maintenance person (work time) as the work content, and compares the time with the standard time required for the work (hereinafter, standard work time) to determine the suitability (or validity) of the work time. 
     In this case, for example, the determination unit  352  may perform the determination process using a checklist CL 3  illustrated in  FIG. 15 . Here,  FIG. 15  is a diagram illustrating an example of the checklist CL 3 . As illustrated in  FIG. 15 , the checklist CL 3  holds, for each work item, a work content, an execution status, a standard work time, a work time, a difference, an improvement point, and the like. 
     Here, the standard work time means a standard time required for work of the work item and is set in advance for each work item. The work time is the time actually required for the work by the maintenance person and is transmitted from the POS terminal  10 , together with the work content. As the difference, a value obtained by subtracting the standard work time from the work time is registered. In addition, flag information is registered in the improvement point when the value of the difference exceeds a threshold. 
     In the POS terminal  10 , the work content acquisition unit  151  acquires the time as the work time at each of the start time and the end time of the work, so that the start time and the end time of the work are transmitted by visible light communication, along with the work content. 
     On the other hand, in the maintenance terminal  30 , when the receiving unit  351  receives the work content indicating the start of the work, the determination unit  352  specifies the work content (work item) being performed on the POS terminal  10  as in the above-described embodiment. The execution status is changed to “work in progress”, and the start time is stored. Further, when receiving the work content indicating the end of the work for the same work item, the determination unit  352  changes the execution status to “completed” and registers the time obtained by subtracting the previously stored start time from the end time as the work time. 
     Further, the determination unit  352  calculates a time obtained by subtracting the standard work time from the time registered as the work time and registers the calculation result as a difference. Then, if the time registered in the difference exceeds a predetermined threshold (for example, one minute), the determination unit  352  determines that the difference is inappropriate and registers the flag information in the improvement point column. 
     For example, the checklist CL 3  in  FIG. 12  illustrates an example in which the threshold is set to one minute. In the checklist CL 3 , since only the difference of the work item “ 075 ” exceeds the threshold, the flag information is added to the work item “ 075 ”. 
     In this case, the output unit  353  may display the above-described checklist CL 3  as a determination result of the determination unit  352 . In addition, the output unit  353  may display a screen for prompting improvement of the work time by, for example, highlighting and displaying the work item for which the flag information is registered in the improvement point column. Also, the output unit  353  may display a screen that clearly indicates work items that were efficiently performed by highlighting and displaying the work items in which the work was completed in a shorter time period than the standard work time. 
     Thus, the maintenance person using the maintenance terminal  30  can easily grasp the work items for which the work method should be improved and the work items that were able to be performed efficiently by looking at the display unit  309 . Therefore, in the present modification, the efficiency of the work performed by the maintenance person on the POS terminal  10  can be improved. 
     (Modification 3) 
     In the above-described embodiment, the case where the maintenance terminal  30  records and determines the work status of the POS terminal  10  is described. However, another device connected to the maintenance terminal  30  may record and determine the work status of the POS terminal  10 . 
       FIG. 16  is a diagram illustrating an example of a maintenance system  3  according to the present modification. In  FIG. 16 , the maintenance terminal  30  is connected to a maintenance management server  70  via a network N 4  such as a public communication network different from the network N 1 . The maintenance management server  70  is, for example, a server device of a company to which the maintenance person belongs and manages maintenance and inspection work performed by each maintenance person. The maintenance management server  70  has the same hardware configuration as the server device  20  and stores the above-described checklist CL 1  and the like in a storage unit (not shown). 
     In the configuration of  FIG. 16 , for example, the maintenance management server  70  may record and determine the work status of the POS terminal  10 . In this case, the maintenance terminal  30  transmits the work content received by the function of the receiving unit  351  to the maintenance management server  70  via the network N 4 . 
     On the other hand, the maintenance management server  70  includes the above-described determination unit  352  and the like as functional units. The determination unit  352  of the maintenance management server  70  performs the same process as the above-described determination unit  352  of the maintenance terminal  30  based on the checklist CL 1  and the work content transmitted from the maintenance terminal  30 . Then, the process result of the determination unit  352  of the maintenance management server  70  is transmitted to the maintenance terminal  30  and the output unit  353  of the maintenance terminal  30  causes the display unit  309  to display a screen based on the determination result of the determination unit  352 . 
     That is, the maintenance management server  70  functions as an example of the information processing device, acquires the work content being performed on the POS terminal  10  via the maintenance terminal  30 , and outputs the determination result on the suitability of the work content via the maintenance terminal  30 . 
     According to this modification, the same effects as those of the above-described embodiments can be obtained. Further, according to the present modification, the maintenance and inspection work performed by each maintenance person can be collectively managed by the maintenance management server  70 , and the process load on the maintenance terminal  30  can be reduced, so that the efficiency of the entire system can be improved. 
     (Modification 4) 
     In the above-described embodiment, an example in which LEDs are used as the light sources of the backlight  1101  and the lighting device  40  is described, but the type of the light source is not limited thereto. However, it is preferable to use a light source that can be modulated in a high frequency band where human eyes do not sense flickering. 
     In the above-described embodiment, an example in which visible light communication is performed using the backlight  1101  of the clerk display unit  110  is described. However, the light source of the POS terminal  10  used for visible light communication is not limited thereto. For example, visible light communication may be performed using the backlight of the customer display unit  111 . For example, visible light communication may be performed using a light source such as an indicator lamp included in a device such as the printer  112 . 
     (Modification 5) 
     In the above-described embodiment, the POS terminal  10  performs the visible light communication using both the clerk display unit  110  (backlight  1101 ) and the light source device of the lighting device  40  connected to the own device. However, the present disclosure is not limited to this configuration, and the POS terminal  10  may be configured to perform visible light communication using one of the light source devices of the clerk display unit  110  (backlight  1101 ) and the lighting device  40 . 
     In this case, for example, the control unit  100  of the POS terminal  10  may cause the clerk display unit  110  to display a selection screen for selecting a light source device used for visible light communication from the light source devices such as the backlight  1101  and the lighting device  40  connected to the own device. Then, the transmission unit  152 , the first modulation unit  153 , and the first light source control unit  154  may perform control such that visible light communication is performed using the light source device selected on the selection screen. 
     (Modification 6) 
     In the above-described embodiment, the device to be maintained is the POS terminal  10 , but the device to be maintained is not limited to the POS terminal  10 . For example, devices such as the server device  20  and a personal computer (PC) (not shown) may be targeted for maintenance. Also in this case, by adopting the same system configuration and device configuration as in the above-described embodiments, the same effects as above can be obtained. 
     (Modification 7) 
     In the above-described embodiment, the POS terminal  10  performs the visible light communication by the lighting device  40  via the server device  20 . However, the present disclosure is not limited thereto, and the POS terminal  10  may directly control the light emission of the lighting device  40 . In this case, for example, the POS terminal  10  and the lighting device  40  are connected via a control line or the like, and the first modulation unit  153  and the first light source control unit  154  perform visible light communication using the lighting device  40 . Thereby, since the setting contents of the setting change operation performed by the POS terminal  10  can be transmitted to the maintenance terminal  30  by visible light communication by the lighting device  40 , the same effect as in the above-described embodiment can be obtained. 
     When the configuration of the present modification is adopted, the transmission unit  152  of the POS terminal  10  is not required, and thus the transmission unit  152  may be invalidated or removed from the POS terminal  10 . 
     (Modification 8) 
     In the above-described embodiment, the case where the visible light communication is used for transmitting and receiving the work content is described. However, in an environment where the direct connection between the POS terminal  10  and the maintenance terminal  30  is allowed, the work content may be transmitted and received using a communication method other than the visible light communication. 
     For example, in an environment where the connection of the maintenance terminal  30  to the network N 1  (see  FIG. 1 ) is allowed, the work content transmitted from the POS terminal  10  may be transmitted via the network N 1  by connecting the maintenance terminal  30  to the network N 1 . 
     In this case, the transmission unit  152  of the POS terminal  10  transmits the work content acquired by the work content acquisition unit  151  to the maintenance terminal  30  via the network N 1 . The receiving unit  351  of the maintenance terminal  30  receives the work content transmitted from the POS terminal  10  via the network N 1 . 
     Further, for example, when the POS terminal  10  and the maintenance terminal  30  include a communication device (hereinafter, referred to as a short-range communication unit) for performing short-range wireless communication such as Bluetooth (registered trademark), the work content may be transmitted and received using the short-range wireless communication. 
     In this case, the transmission unit  152  of the POS terminal  10  transmits the work content acquired by the work content acquisition unit  151  to the maintenance terminal  30  via the short-range communication unit. The receiving unit  351  of the maintenance terminal  30  receives the work content transmitted from the POS terminal  10  via the short-range communication unit. 
     According to the present modification, the same effects as those of the above-described embodiments can be obtained. In this modification, since the first modulation unit  153  and the first light source control unit  154  of the POS terminal  10  become unnecessary, the function may be invalidated or removed from the POS terminal  10 . 
     The program executed by each device of the above-described embodiments is provided by being incorporated in a ROM or the like in advance. The program executed by each device of the above-described embodiments may be provided by being recorded on a computer readable recording medium such as a CD-ROM, a flexible disk (FD), a CDR, and a digital versatile disk (DVD) in an installable format or an executable format file. 
     Furthermore, the program executed by each device of the above-described embodiments may be stored on a computer connected to a network such as the Internet and may be provided by being downloaded via the network. Further, the program executed by each device of the above-described embodiments may be provided or distributed via a network such as the Internet. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.