Patent Publication Number: US-2022215364-A1

Title: Electronic device, management method of electronic device, and program

Description:
TECHNICAL FIELD 
     The present invention relates to an electronic device, a method for managing an electronic device, and a program. 
     BACKGROUND ART 
     In recent years, electronic devices such as projectors and displays have been utilized in various places. Generally, these electronic devices are sold to users and then utilized in many cases. 
     Patent Literature 1 describes a system for a user to utilize a service that is charged for. In this system, processing relating to charging of the user is performed through a centralized management platform. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1 
     Published Japanese Translation No. 2004-545014 of the PCT International Publication 
     SUMMARY OF INVENTION 
     Technical Problem 
     The inventors of the present invention have considered lending an electronic device to a user and a consideration payment being made in exchange at the time of lending according to the operation conditions and a usage time of the electronic device. In this case, the user may want to temporarily change the operation conditions of electronic device in some cases. On the other hand, connecting the electronic device to the Internet may not be possible depending on a usage environment at the time of using the electronic device in some cases. 
     An object of the present invention is to be able to temporarily change the operation conditions of an electronic device even when the electronic device cannot be connected to the Internet when the electronic device is lent and a consideration payment is made in exchange at the time of lending according to the operation conditions and a usage time of the electronic device. 
     Solution to Problem 
     According to the present invention, 
     an electronic device includes: 
     an operation condition storage storing information of operation conditions which specifies the operation conditions of the electronic device; 
     a time information storage storing time information that is information for specifying a usable time or an expiration period of the electronic device in the information of operation conditions; 
     a change input receiving a change input for temporarily changing the information of operation conditions and receive change period information which specifies an applicable period of the changed information of operation conditions; and 
     a changer changing the time information using the changed information of operation conditions and the applicable period. 
     According to the present invention, 
     a management method of an electronic device includes: 
     storing information of operation conditions which specifies the operation conditions of the electronic device; 
     storing time information that is information for specifying a usable time or an expiration period of the electronic device in the information of operation conditions; 
     receiving a change input for temporarily changing the information of operation conditions and receive change period information which specifies an applicable period of changed information of operation conditions; and 
     changing the time information using the changed information of operation conditions and the applicable period. 
     According to the present invention, 
     a program causes an electronic device to perform: 
     a function of storing information of operation conditions which specifies the operation conditions of the electronic device; 
     a function of storing time information that is information for specifying a usable time or an expiration period of the electronic device in the information of operation conditions; 
     a function of receiving a change input for temporarily changing the information of operation conditions and receive change period information which specifies an applicable period of changed information of operation conditions; and 
     a function of changing the time information using the changed information of operation conditions and the applicable period. 
     Advantageous Effects of Invention 
     According to the present invention, it is possible to temporarily change the operation conditions of an electronic device even when the electronic device cannot be connected to the Internet when the electronic device is lent and a consideration payment is made in exchange at the time of lending according tor the operation conditions and a usage time of the electronic device. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The above-described object, other objects, features, and advantages will be further clarified through preferred embodiments which will be described later and the following accompanying drawings. 
         FIG. 1  is a diagram showing an example of a constitution of a function of an electronic device according to an embodiment. 
         FIG. 2  is a diagram showing an example of information stored in an operation condition storage. 
         FIG. 3  is a diagram showing an example of information stored in a time information storage. 
         FIG. 4  is a block diagram illustrating a constitution of hardware of a main part of the electronic device. 
         FIG. 5  is a diagram showing a first example of processing performed by the electronic device. 
         FIG. 6  is a diagram showing a second example of the processing performed by the electronic device. 
         FIG. 7  is a diagram showing a detailed example of Step S 120  of  FIG. 6 . 
         FIG. 8  is a diagram showing an example of subsequent processing with respect to  FIG. 7 . 
         FIG. 9  is a diagram showing a detailed example of Step S 140  of  FIG. 6 . 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiments of the present invention will be described below with reference to the drawings. Constituent elements that are the same in all of the drawings will be denoted by the same reference numerals and description thereof will be omitted as appropriate. 
       FIG. 1  is a diagram showing an example of a constitution of a function of an electronic device  10  according to an embodiment. The electronic device  10  shown in this drawing is, for example, an office apparatus and lent to a user. The electronic device  10  is, for example, a display apparatus such as a display or a projector, but may a copying machine or a multifunctional machine having a copying function and a fax function. 
     In this embodiment, the electronic device  10  is not connected to the Internet. For this reason, it is difficult to charge for the electronic device  10  on a pay-as-you-go basis. Thus, the user makes a consideration payment in advance in exchange for the lending (hereinafter referred to as a “prepaid money amount”). A usable time of the electronic device  10  is determined in accordance with the prepaid money amount. Furthermore, the electronic device  10  stores information (hereinafter referred to as “time information”) for specifying a current usable time (the remaining time of a usable time) and renews the information in accordance with a total time for which the electronic device  10  has already been used. In addition, a controller of the electronic device  10  makes a function as the electronic device  10  stop working when the usable time becomes zero. 
     A consideration payment for the electronic device  10  per unit time can be changed depending on an operation state of the electronic device  10  when the electronic device  10  is used. Operation states available for the electronic device  10  may vary depending on a type of contract selected by the user (for example, a contract plan). As an example, when the lifespan of the parts constituting the electronic device  10  differs depending on an operation state (for example, a ratio of an available output to a rated output), a unit price per unit time varies depending on an operation state permitted by the contract. For this reason, even if prepaid money amounts are the same, the usable time of the electronic device  10  may vary depending on the selected contract plan. In this embodiment, the electronic device  10  stores information for specifying the selected type of contract (hereinafter referred to as “information of operation conditions”). 
     For example, when the electronic device  10  is a projector, a light source is prone to deterioration. Furthermore, an output of the light source available for the electronic device  10  (that is, the brightness of a projector) varies depending on the contract plan. For this reason, the usable time or the prepaid money amount of the electronic device  10  varies depending on the contract plan. This output is determined, for example, on the basis of the rated output of the light source. 
     On the other hand, some users of the electronic device  10  may want to temporarily change the operation conditions of the electronic device  10  during a contract period in some cases. In this case, a user makes an input to the electronic device  10  to temporarily change the operation conditions. Furthermore, the electronic device  10  measures a length of a time for which the electronic device  10  is actually used under the changed operation conditions (hereinafter referred to as an “actual usage time”) and corrects the usable time in accordance with the length of the actual usage time. 
     To be specific, the electronic device  10  includes an operation condition storage  110 , a time information storage  120 , a change input  130 , and a changer  140 . The operation condition storage  110  stores information of operation conditions of the electronic device  10 . The time information storage  120  stores time information in the information of operation conditions. When the electronic device  10  can be connected to the Internet, the information stored in the operation condition storage  110  and the information stored in the time information storage  120  may be regularly stored in an external server of the electronic device  10 . The change input  130  receives a change input for temporarily changing the information of operation conditions and receives change period information for specifying an applicable period of the changed information of operation conditions. These inputs are performed, for example, by operating, by a user, an input device (for example, a button or a touch panel) provided in the electronic device  10 . The changer  140  changes the time information using the changed information of operation conditions and the applicable period. 
     Also, when the electronic device  10  is used even when the operation conditions are not changed, the changer  140  renews the time information in accordance with the usage time thereof. For example, when the time information includes the usable time, the changer  140  subtracts the used time from the usable time. Furthermore, when the usable time includes the remaining amount of the prepaid money amount, the changer  140  subtracts a value obtained by multiplying the used time by a current unit price of the contract plan from the remaining amount. 
     In the example shown in this drawing, the electronic device  10  further includes an output  150  and a display  160 . The output  150  outputs at least one of the usable time and an expiration period calculated using the usable time. An example of an output destination using the output  150  is the display  160 . The display  160  is, for example, a liquid crystal display or a touch panel (in this case, also serves as an input device) and displays information output by the output  150 . Thus, for example, a user of the electronic device  10  can use the electronic device  10  and then confirm at least one of the usable time and the expiration period after the use. 
     When the electronic device  10  is a display, the display  160  may be a display panel as a display. Furthermore, when the electronic device  10  is a projector, the display  160  may be a projection unit of the projector. In these cases, it is preferable that the output  150  output the above-described information at a timing at which a user starts using the electronic device  10  (that is, when a power button is turned on) and when the user ends the use of the electronic device  10  (that is, when the power button is turned off). 
     In the example shown in this drawing, the electronic device  10  further includes an initial input  170  and a notifier  180 . The initial input  170  acquires first information of operation conditions, that is, information of operation conditions at the time of performing lending, stores the information of operation conditions in the operation condition storage  110 , acquires first time information, that is, time information at the time of performing lending, and stores the time information in the time information storage  120 . The electronic device  10  may not be connected to the Internet in some cases. In this case, the initial input  170  acquires the information of operation conditions at the time of performing lending and the time information at the time of performing lending from a portable storage apparatus (for example, a portable memory). Here, when the electronic device  10  can be connected to the Internet, the initial input  170  may acquire the information of operation conditions at the time of performing lending and the time information at the time of making a contract over the Internet. 
     The notifier  180  outputs a prescribed notification when the time reaches a timing at which the contract for using the electronic device  10  ends. This notification is, for example, to display a prescribed character string on the display  160 . The notifier  180  determines whether the time has reached the timing at which the contract for using the electronic device  10  ends on the basis of a determination concerning whether a difference between the expiration period and a current date and time of the electronic device determined through the time information satisfies a reference (as an example, whether the difference is less than or equal to a prescribed value). 
       FIG. 2  is a diagram showing an example of information stored in the operation condition storage  110 . In the example shown in this drawing, the operation condition storage  110  stores a “coefficient” or a “unit price” as the information of operation conditions for each range of the operation conditions of the electronic device  10 . When the range of the operation conditions is determined through the contract plan, the operation condition storage  110  may further store a contract plan name. 
     For example, when the electronic device  10  is a projector, the operation conditions of the electronic device  10  includes a model number of the electronic device  10 , a model number of a light source included in the electronic device  10 , and an output available for the light source (for example, a relative value based on a rated output). 
     The “coefficient” is a ratio of a unit price within the range of the operation conditions that are references or an operable time when the same prepaid money amount is paid to the unit price within the range. Furthermore, the time information indicates the usable time. In addition, the changer  140  determines a coefficient on the basis of a combination of the unchanged information of operation conditions and the changed information of operation conditions and calculates the changed usable time using this coefficient. 
     For example, when the “coefficient” stored in the operation condition storage  110  is the ratio of the unit price, the changer  140  determines the “unchanged ‘coefficient’/the changed ‘coefficient’” as a coefficient used herein. Furthermore, when the “coefficient” stored in the operation condition storage  110  is the ratio of the operable time, the changer  140  determines the “changed ‘coefficient’/the unchanged ‘coefficient’” as a coefficient used herein. Furthermore, the changer  140  calculates an amount of decrease in the usable time by multiplying the actual usage time of the electronic device  10  under the changed operation conditions by this coefficient. In addition, the changed usable time is calculated by subtracting this amount of decrease from the usable time stored in the time information storage  120 . 
     Also, “unit price” (an example of a constant) is a unit price per unit actual usage time in the contract plan. In this case, the time information is the remaining amount of the prepaid money amount (that is, a value obtained by subtracting the “actual usage time of the electronic device  10  so far”×the “unit price per hour” from the prepaid money amount). Furthermore, the changer  140  calculates an amount of decrease in the remaining amount from this remaining amount by multiplying the actual usage time of the electronic device  10  under the changed operation conditions by the “unit price” under the changed operation conditions. In addition, the changer  140  calculates the changed remaining amount by subtracting the calculated amount of decrease from the remaining amount stored in the time information storage  120 . 
       FIG. 3  is a diagram showing an example of information stored in the time information storage  120 . In the example shown in this drawing, the time information storage  120  stores the currently selected range of the operation conditions, the remaining amount, the usable time, and the expiration period. Here, it may not be possible to set the expiration period depending on the type of electronic device  10  and the contract plan in some cases. In this case, the time information storage  120  does not store the expiration period. 
     Also, the time information storage  120  stores an additional consideration payment to be paid to an owner of the electronic device  10  by a user of the electronic device  10  at the time of the next contract renewal. This additional consideration payment may occur when the user of the electronic device  10  temporarily changes the operation conditions of the electronic device  10 , for example, as will be described later. 
       FIG. 4  is a block diagram illustrating a constitution of hardware of a main part of the electronic device  10 . This main part has a bus  1010 , processors  1020 , a memory  1030 , a storage device  1040 , an input/output interface  1050 , and a network interface  1060 . 
     The bus  1010  is a data transmission path through which the processors  1020 , the memory  1030 , the storage device  1040 , the input/output interface  1050 , and the network interface  1060  transmit and receive data to and from each other. Here, a method for connecting the processors  1020  or the like to each other is not limited to connection through the bus. 
     The processors  1020  is a processor realized through a central processing unit (CPU), a graphics processing unit (GPU), or the like. 
     The memory  1030  is a main storage apparatus realized through a random access memory (RAM) or the like. 
     The storage device  1040  is an auxiliary storage apparatus realized through a hard disk drive (HDD), a solid state drive (SSD), a memory card, a read only memory (ROM), or the like. The storage device  1040  stores program modules which realize functions of (for example, the change input  130 , the changer  140 , the output  150 , the initial input  170 , and the notifier  180 ) of the electronic device  10 . When the processors  1020  reads each of these program modules on the memory  1030  and executes the program module, each of the functions corresponding to each of the program modules is realized. Furthermore, the storage device  1040  also functions as various storages (for example, the operation condition storage  110  and the time information storage  120 ). 
     The input/output interface  1050  is an interface through which the main part of the electronic device  10  is connected to various input/output machines (for example, the display  160 ). 
     The network interface  1060  is an interface through which the electronic device  10  is connected to other apparatuses on the network. Here, the network interface  1060  may not be utilized in some cases. 
       FIG. 5  is a diagram showing a first example of processing performed by the electronic device  10 . The process shown in this drawing is a process in which the electronic device  10  acquires first information of operation conditions and first time information (hereinafter referred to as “initial conditions”). 
     The initial conditions are stored in a portable memory. A user of the electronic device  10  or an owner of the electronic device  10  (in the case of a corporation, he/she may be a sales representative of the corporation in some cases) inserts a portable memory having the initial conditions stored therein into the terminal of the electronic device  10 . In this memory, an electronic signature is associated with the initial conditions. Furthermore, when the initial conditions and the electronic signature are read (Step S 10 ) and the electronic device  10  succeeds in authenticating the electronic signature (Step S 20 : Yes), the initial input  170  of the electronic device  10  sets the first operation conditions included in the initial conditions in the electronic device  10  (Step S 30 ). Moreover, the initial input  170  stores first information of operation conditions in the operation condition storage  110  and stores first time information in the time information storage  120  (Step S 40 ). 
     As described above, the process shown in Step S 10  may be performed over the Internet. 
       FIG. 6  is a diagram showing a second example of processing performed by the electronic device  10 . The process shown in the drawing is a process performed while the electronic device  10  is in use. 
     First, a user of the electronic device  10  turns on the power of the electronic device  10  and performs a prescribed operation as necessary. Thus, the use of the electronic device  10  is started (Step S 100 ). After that, the changer  140  of the electronic device  10  counts the actual usage time of the electronic device  10  for each of the operation conditions until the use of the electronic device  10  is completed (Step S 120 ). In addition, after the use of the electronic device  10  is completed, the changer  140  renews the time information (Step S 140 ). 
       FIG. 7  is a flowchart showing an example of the process performed in Step S 120  of  FIG. 6 . When a user does not make an input to change the operation conditions of the electronic device  10  (Step S 122 : No), the changer  140  of the electronic device  10  adds a time during which the electronic device  10  has been used this time to the actual usage time under the current operation conditions (Step  132 ). 
     A user may want to change the operation conditions of the electronic device  10  while the electronic device  10  is being used. In this case, the user makes an input to change the operation conditions of an operation unit of the electronic device  10  (Step S 122 : Yes). For example, when the electronic device  10  is a display, the user makes an input to change the brightness of the display, for example, via an operation button. Furthermore, when the electronic device  10  is a projector, the user makes an input to change the brightness of the light source, for example, via an operation button. 
     Here, the changer  140  confirms whether the current operation conditions are within the range of the contract. When it is confirmed that the current operation conditions are outside of the range of the contract (Step S 124 : No), the changer  140  performs the process shown in  FIG. 8 . 
     When it is confirmed that the current operation conditions are within the range of the contract (Step S 124 : Yes), the changer  140  confirms whether the operation conditions have reached an upper limit or a lower limit of the current range of the contract (Step S 126 ). When it is confirmed that the operation conditions have not reached the upper limit or the lower limit, that is, the operation conditions are within the current range of the contract (Step S 126 : No), then the changer  140  adds a time during which the electronic device  10  has been used to the actual usage time under the current operation conditions (Step S 132 ). 
     On the other hand, when it is confirmed that the operation conditions have reached the upper limit (or lower limit) of the current range of the contract (Step S 126 : Yes), the changer  140  maintains the operation conditions at the upper limit (or lower limit) until there is a specifically identified input (for example, an input of a button different from the operation button to change the operation conditions) (Step S 128 : No) even if the change input of the operation conditions is continued and adds a time during which the electronic device  10  has been used this time to the actual usage time under the current operation conditions (Step S 132 ). On the other hand, in the case in which it is confirmed that there is the specifically identified input (Step S 128 : Yes), the changer  140 , when it is confirmed that the change input of the operation conditions is continued (or at the same time as a specifically identified dormitory), the changer  140  changes the operation conditions outside of the current range of the contract in accordance with the change input (Step S 130 ). As an example, the changer  140  makes the brightness of the display larger than the upper limit of the contract. Furthermore, as another example, the changer  140  makes the brightness of the light source of the projector larger than the upper limit of the contract. In addition, after the operation conditions have been changed, the changer  140  adds a time during which the electronic device  10  has been used to the actual usage time under the changed operation conditions (Step S 132 ). In other words, the timing at which the input for making the operation conditions be outside of the range of the contract has been performed also indicates a timing at which the applicable period under the changed operation conditions is started. 
     The changer  140  repeatedly performs the processes shown in Step S 122  to Step S 132  until an input for completing the use of the electronic device  10  (for example, turning off the power button) is made (Step S 134 : No). On the other hand, when the input for completing the use of the electronic device  10  is made (Step S 134 : Yes), the changer  140  confirms the current operation conditions. When it is confirmed that the current operation conditions are outside of the range of the contract (Step S 136 : Yes), the operation conditions of the electronic device  10  return within the range of the contract, for example, the upper limit or the lower limit of the range (Step S 138 ). In other words, the input for completing the use of the electronic device  10  also serves as the input for returning the operation conditions to within the range of the contract. Moreover, this input also indicates the timing at which the applicable period ends under the changed operation conditions. After that, the electronic device  10  performs the process shown in Step S 140 . 
     When the electronic device  10  is a projector, the input for completing the use of the electronic device  10  may be an input for turning off the light source. Furthermore, the process shown in Step S 138  may be performed immediately after the next turned-on of the power supply. 
       FIG. 8  is a flowchart showing an example of the process after the process of Step S 124  of  FIG. 7 . When it is confirmed that the current operation conditions are outside of the range of the contract (Step S 124 : No in  FIG. 7 ) and a user&#39;s input indicates that the operation conditions are changed to be away from the range of the contract (Step S 200 : 
     No), the changer  140  adds a time during which the electronic device  10  has been used this time to the actual usage time under the current operation conditions (Step  132  in  FIG. 7 ). On the other hand, when it is confirmed that the current operation conditions are outside of the range of the contract (Step S 124 : No in  FIG. 7 ), the user&#39;s input indicates that the operation conditions are changed to be away from the range of the contract (Step S 200 : Yes), and the operation conditions return within the range of the contract (Step S 202 : Yes), then the changer  140  adds a time during which the electronic device  10  has been used to an operation actual time corresponding to the range of the contract (Step S 132  in  FIG. 7 ). When it is confirmed that the operation conditions do not return within the range of the contract (Step S 202 : No), then the changer  140  adds a time during which the electronic device  10  has been used to the operation actual time corresponding to the current range (Step S 132  in  FIG. 7 ). 
       FIG. 9  is a flowchart showing an example of the process performed in Step S 140  of  FIG. 6 . First, the changer  140  calculates an amount of decrease of the time information using the actual usage time of the operation conditions for each of the ranges of the operation conditions. An example of a method for calculating an amount of decrease of the time information is as described with reference to  FIG. 2  (Step S 142 ). Subsequently, the changer  140  renews the time information by subtracting the sum of these amounts of decrease from the time information stored in the time information storage  120  (Step S 144 ). Here, the changer  140  makes it possible to return the time information to the state before the renewal. 
     Here, the renewed time information may be negative in some cases. When it is confirmed that the renewed time information is negative (Step S 146 : No), a consideration payment corresponding to this negative amount is added to an additional consideration payment amount stored in the time information storage  120  and the time information renewed in Step S 144  is returned to the original time information (Step S 152 ). For example, when the time information is the remaining amount of the prepaid money amount, the negative amount is an additional consideration payment as it is. On the other hand, when the time information is the usable time, the changer  140  calculates an additional consideration payment amount, for example, by multiplying the unit price under the operation conditions in a state in which the contract has been made by this negative amount. 
     On the other hand, when the renewed time information is positive or 0 (Step S 146 : Yes), the changer  140  causes a screen for allowing a user to select a consideration payment method for the use of the electronic device  10  this time to be displayed on the display  160  of the electronic device  10 . A selection option is a determination concerning whether to return the time information to the original time information by performing payment at the time of performing the next contract renewal. When it is confirmed that the user selects to perform payment at the time of performing the next contract renewal (Step S 150 : Yes), the changer  140  adds the consideration payment according to the amount of decrease calculated in Step S 142  to the additional consideration payment amount stored in the time information storage  120  and returns the time information renewed in Step S 144  to the original time information (Step S 152 ). On the other hand, when it is confirmed that the user does not select to perform payment at the time of performing the next contract renewal (Step S 150 : No), the changer  140  decides the renewed time information. 
     As described above, according to this embodiment, the electronic device  10  stores the information (time information) which specifies the usable time of the electronic device  10  when the electronic device  10  is lent to the user. Moreover, if the operation conditions of the electronic device  10 , that is, the contract plan is temporarily changed, when calculation according to the changed operation conditions and the actual usage time under the changed operation conditions is performed, the time information is renewed. Therefore, even if the electronic device  10  is not connected to the Internet, a user of the electronic device  10  can temporarily use the operation conditions outside of the range determined in the contract. 
     Although the embodiments of the present invention have been described above with reference to the drawings, these embodiments are examples of the present invention and various constitutions other than the above constitutions can be adopted. 
     Also, although a plurality of steps (processes) are described in order in the plurality of flowcharts used in the above description, the execution order of the steps performed in each of the embodiments is not limited to the order in the description. In each of the embodiments, the order of the illustrated steps can be changed within a range in which the contents are not hindered. Furthermore, the above-described embodiments can be combined as long as the contents do not conflict with each other. 
     Although some or all of the above embodiments may also be additionally described as follows, the present invention is not limited to the following description. 
     1. An electronic device, comprising: 
     an operation condition storage storing information of operation conditions which specifying the operation conditions of the electronic device; 
     a time information storage storing time information that is information for specifying at least one of a usable time and expiration period of the electronic device in the information of operation conditions; 
     a change input receiving a change input for temporarily changing the information of operation conditions and receive change period information which specifying an applicable period of the changed information of operation conditions; and 
     a changer changing the time information using the changed information of operation conditions and the applicable period. 
     2. The electronic device according to the above 1, wherein the time information indicates a usable time, and 
     the changer determines a coefficient on the basis of a combination of unchanged information of operation conditions and changed information of operation conditions and calculates changed time information using the coefficient. 
     3. The electronic device according to the above 1, wherein the time information indicates the remaining amount of a prepaid money amount, and 
     the changer calculates changed time information using a constant determined on the basis of the remaining amount and the changed information of operation conditions. 
     4. The electronic device according to any one of the above 1 to 3, the changer calculates the time information after the applicable period has expired, 
     further receives a selection input concerning whether to set the change of the time information or to perform another procedure without changing the time information, and 
     decides the renewal of the time information when receiving an input for setting the change of the time information. 
     5. The electronic device according to any one of the above 1 to 4, wherein the information of operation conditions indicates a range of the operation conditions, and 
     the change input is an input for making the operation conditions be outside of the range and a timing at which the input has been made indicates a timing at which the applicable period is started. 
     6. The electronic device according to the above 5, wherein a timing at which the applicable period ends is a timing at which an input for returning the operation conditions to within the range is performed. 
     7. The electronic device according to any one of the above 1 to 6, which includes an initial input acquiring the first information of operation conditions, storing the acquired first information of operation conditions in the operation condition storage, acquiring the first time information, and storing the acquired first time information in the time information storage. 
     8. The electronic device according to the above 7, wherein the first information of operation conditions and the first time information have electronic signatures attached thereto, and 
     the initial input stores the first operation conditions in the operation condition storage and stores the first time information in the time information storage when the electronic signature is authenticated. 
     9. The electronic device according to any one of the above 1 to 8, wherein the electronic device is a display apparatus or a projector. 
     10. A management method of an electronic device, which includes: 
     storing information of operation conditions which specifies the operation conditions of the electronic device; 
     storing time information that is information for specifying at least one of a usable time and expiration period of the electronic device in the information of operation conditions; 
     receiving a change input for temporarily changing the information of operation conditions and receive change period information which specifies an applicable period of changed information of operation conditions; and 
     changing the time information using the changed information of operation conditions and the applicable period. 
     11. The management method of an electronic device according to the above 10, wherein the time information indicates a usable time, and 
     the electronic device determines a coefficient on the basis of a combination of unchanged information of operation conditions and changed information of operation conditions and calculates changed time information using the coefficient. 
     12. The management method of an electronic device according to the above 10, wherein the time information indicates the remaining amount of a prepaid money amount, and 
     the electronic device calculates changed time information using a constant determined on the basis of the remaining amount and the changed information of operation conditions. 
     13. The management method of an electronic device according to any one of the above 10 to 12, wherein the electronic device calculates the time information after the applicable period has expired, 
     further receives a selection input concerning whether to set the change of the time information or to perform another procedure without changing the time information, and 
     decides the renewal of the time information when receiving an input for setting the change of the time information. 
     14. The management method of an electronic device according to any one of the above 10 to 13, wherein the information of operation conditions indicates a range of the operation conditions, and 
     the change input is an input for making the operation conditions be outside of the range and a timing at which the input is made indicates a timing at which the applicable period is started. 
     15. The management method of an electronic device according to the above 14, wherein a timing at which the applicable period ends is a timing at which an input for returning the operation conditions to within the range is performed. 
     16. The management method of an electronic device according to any one of the above 10 to 15, wherein the electronic device acquires and stores the first information of operation conditions and acquires and stores the first time information. 
     17. The management method of an electronic device according to the above 16, wherein the first information of operation conditions and the first time information have electronic signatures attached thereto, and 
     the electronic device stores the first operation conditions and stores the first time information when the electronic signature is authenticated. 
     18. The management method of an electronic device according to any one of the above 10 to 17, wherein the electronic device is a display apparatus or a projector. 
     19. A program causing an electronic device to serve: 
     a function of storing information of operation conditions which specifies the operation conditions of the electronic device; 
     a function of storing time information that is information for specifying at least one of a usable time and expiration period of the electronic device in the information of operation conditions; 
     a function of receiving a change input for temporarily changing the information of operation conditions and receive change period information which specifies an applicable period of changed information of operation conditions; and 
     a function of changing the time information using the changed information of operation conditions and the applicable period. 
     20. The program according to the above 19, wherein the time information indicates a usable time; and 
     the electronic device is caused to determine a coefficient on the basis of a combination of unchanged information of operation conditions and changed information of operation conditions and to calculate changed time information using the coefficient. 
     21. The program according to the above 19, wherein the time information indicates the remaining amount of a prepaid money amount, and 
     the electronic device is caused to calculate changed time information on the basis of a constant determined on the basis of the remaining amount and changed information of operation conditions. 
     22. The program according to any one of the above 19 to 21, wherein the electronic device is caused to calculate the time information after the applicable period has expired, 
     to further receive a selection input concerning whether to set the change of the time information or to perform another procedure without changing the time information, and 
     to decide the renewal of the time information when an input for setting the change of the time information is received. 
     23. The program according to any one of the above 19 to 22, wherein the information of operation conditions indicates a range of the operation conditions, and 
     the change input is an input for making the operation conditions be outside of the range and a timing at which the input is performed indicates a timing at which the applicable period is started. 
     24. The program according to the above 23, wherein a timing at which the applicable period ends is a timing at which an input for returning the operation conditions to within the range is performed. 
     25. The program according to any one of the above 19 to 24, wherein the electronic device is caused to acquire and store the first information of operation conditions and to acquire and store the first time information. 
     26. The program according to the above 25, wherein the first information of operation conditions and the first time information have electronic signatures attached thereto, and 
     the electronic device is caused to store the first operation conditions and to store the first time information when the electronic signature is authenticated. 
     27. The program according to any one of the above 19 to 26, wherein the electronic device is a display apparatus or a projector. 
     REFERENCE SIGNS LIST 
       10  Electronic device 
       110  Operation condition storage 
       120  Time information storage 
       130  Change input 
       140  Changer 
       150  Output 
       160  Display 
       170  Initial input 
       180  Notifier