JP2017092516A - Display device, and data protection method for display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device which prevents leakage of information by improving security of data to be stored in the device.SOLUTION: A projector 100 configured to display an image based on image data comprises: a storage part 170 for storing encrypted data; a GPS positioning part 135 for identifying a position of the projector 100; and an encryption processing part 165 for discriminating whether the position identified by the GPS positioning part 135 is a preset position. In the case where it is discriminated that the identified position is not the preset position, the encryption processing part 165 limits decryption of the data stored in the storage part 170.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a display device and a data protection method for the display device.

In recent years, display devices that display images have been reduced in size and weight, and the number of devices that can be carried has increased. For this reason, various functions such as a function for preventing theft and a function for preventing unauthorized use have been mounted on display devices (see, for example, Patent Document 1).
Patent Document 1 includes a projection type projector including a security unit, and an unauthorized use prevention device provided separately from the projection type projector, and a position calculated by the security unit and a position calculated by the unauthorized use prevention device. A system for preventing unauthorized use of a projection type projector is disclosed in which it is determined whether or not the distance between the projection type projector and the projection distance is equal to or greater than a threshold distance, and whether the light source of the projection type projector is turned on or off.

JP 2014-137479 A

By the way, a display device includes a storage device, and can store confidential information such as conference materials and conference contents. For this reason, it is necessary to take measures to prevent leakage of data stored in the display device and to ensure data safety.
The present invention has been made in view of the above circumstances, and provides a display device that improves the safety of data stored in the display device and prevents information leakage, and a data protection method for the display device. Objective.

In order to achieve the above object, a display device of the present invention is a display device that displays an image based on image data, a storage unit that stores encrypted data, and a position specification that specifies a position of the display device A determination unit that determines whether or not the position specified by the position specifying unit is a preset position, and the determination unit determines that the position is not the preset position. A decoding control unit that restricts decoding of the data stored in the storage unit.
ADVANTAGE OF THE INVENTION According to this invention, the safety | security of the data preserve | saved at a display apparatus can be improved and the leakage of information can be prevented.

In the display device, the display unit displays an image based on image data supplied from the outside, and the detection is performed to detect an operation by an indicator on the display surface on which the image is displayed by the display unit. A generation unit that generates image data corresponding to the operation detected by the detection unit, the image data supplied from the outside, and image data corresponding to the operation generated by the generation unit And an encryption unit that encrypts and stores the encrypted data in the storage unit.
According to the present invention, at least one of image data in which an image is displayed on a display surface and image data corresponding to an operation can be encrypted and stored in a storage unit.

In the display device, the encryption unit may determine the position of at least one of the image data supplied from the outside and image data corresponding to the operation generated by the generation unit. It encrypts with the encryption key based on the positional information specified by the part.
According to the present invention, even if the display device is stolen or data is copied without permission, it is impossible to perform decoding at a position other than a preset position. For this reason, it is possible to limit browsing of data at a position other than the position set in advance.

In the display device, the position specified by the position specifying unit is stored in the storage unit when it is determined that the position is set in advance by the determination unit. A processing unit for decoding the data is provided.
According to the present invention, data can be decoded when the position of the display device is a preset position.

Further, according to the present invention, in the display device, the processing unit decrypts the data encrypted with an encryption key based on the position information specified by the position specifying unit, with a decryption key based on the position information. It is characterized by that.
According to the present invention, even if the display device is stolen or data is copied without permission, it is impossible to perform decoding at a position other than a preset position. For this reason, it is possible to limit browsing of data at a position other than the position set in advance.

In the display device, the encryption unit may determine that the position specified by the position specifying unit is not the position set in advance by the determination unit. The data stored in the storage unit is further encrypted.
According to the present invention, even when data is transferred to a third party by unauthorized duplication, loss, theft, etc., it is possible to make the data inaccessible and further improve the safety of information.

In the display device according to the aspect of the invention, the storage unit is configured by a semiconductor memory element, and the decoding control unit is configured such that the position specified by the position specifying unit is set in advance by the determination unit. When it is determined that the position is not the position, a writing process is executed more than a preset number of times on the semiconductor memory element.
According to the present invention, even when data is transferred to a third party by unauthorized duplication, loss, theft, etc., it is possible to make the data inaccessible and further improve the safety of information.

In the display device according to the aspect of the invention, the determination unit determines whether the position specified by the position specifying unit is the position set in advance when the display device is activated. It is characterized by that.
According to the present invention, even when the display device is stolen by a third party and the display device is activated at a position other than a preset position, data browsing can be restricted.

In the display device according to the aspect of the invention, the determination unit may set the specified position in advance when the position specified by the position specifying unit is within a preset range. It is characterized in that it is determined to be in the position.
According to the present invention, a display device can be used within a preset range.

The data protection method for a display device according to the present invention is a data protection method for a display device that displays an image based on image data, the specifying step for specifying the position of the display device, and the position specified by the specifying step. Is a determination step for determining whether or not the position is a preset position, and a memory for storing encrypted data when it is determined by the determination step that the position is not the preset position. And a limiting step for limiting the decoding of the data stored in the unit.
ADVANTAGE OF THE INVENTION According to this invention, the safety | security of the data preserve | saved at a display apparatus can be improved and the leakage of information can be prevented.

The block diagram of a projector. The flowchart which shows the processing flow of a control part. The flowchart which shows the continuation of a processing flow. The flowchart which shows the continuation of a processing flow.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of a projector 100 as a display device.
The projector 100 is placed on a floor or a stand in front of the screen SC (display surface), and projects an image onto the screen SC. In the present embodiment, the image projection destination is described as the screen SC, but it may be a flat projection surface such as a wall or a non-uniform object such as a building or an object.

  An image supply device 200 is connected to the projector 100. The image supply device 200 is a device that supplies image data to the projector 100. The projector 100 projects an image based on image data supplied from the image supply device 200 or image data stored in advance in a storage unit 170 described later on the screen SC. For example, a video playback device, a DVD (Digital Versatile Disk) playback device, a TV tuner device, a CATV (Cable television) set-top box, a video output device such as a video game device, a personal computer, or the like is used as the image supply device 200. It is done.

The projector 100 includes an image input unit 151 to which the image supply device 200 is connected. The image input unit 151 includes a connector for connecting a cable and an interface circuit (both not shown), and inputs image data supplied from the image supply device 200.
The interface provided in the image input unit 151 may be a data communication interface such as Ethernet (registered trademark), IEEE 1394, or USB. The interface of the image input unit 151 may be an interface for image data such as MHL (registered trademark), HDMI (registered trademark), and DisplayPort.
Further, the image input unit 151 may have a configuration including a VGA terminal to which an analog video signal is input and a DVI (Digital Visual Interface) terminal to which digital video data is input as a connector. Further, the image input unit 151 includes an A / D conversion circuit, and when an analog video signal is input via the VGA terminal, the analog video signal is converted into image data by the A / D conversion circuit, and image processing described later is performed. It may be configured to output to the unit 152.

The projector 100 includes a display unit 110 that forms an optical image and displays (projects) the image on the screen SC.
The display unit 110 includes a light source unit 111, a light modulation device 112, and a projection optical system 113. The light source unit 111 includes a light source including a xenon lamp, an ultra high pressure mercury lamp, an LED (Light Emitting Diode), a laser light source, or the like. The light source unit 111 may include a reflector and an auxiliary reflector that guide light emitted from the light source to the light modulation device 112. Further, the light source unit 111 includes a lens group for increasing the optical characteristics of the projection light, a polarizing plate, a light control element that reduces the amount of light emitted from the light source on the path to the light modulation device 112 (both shown) Abbreviation) may be provided.

  The light source unit 111 is driven by the light source driving unit 121. The light source driving unit 121 is connected to the internal bus 180. The light source driving unit 121 turns on and off the light source of the light source unit 111 under the control of the control unit 160.

  The light modulation device 112 includes, for example, three liquid crystal panels corresponding to the three primary colors RGB. The light emitted from the light source unit 111 is separated into three color lights of RGB and is incident on the corresponding liquid crystal panel. The three liquid crystal panels are transmissive liquid crystal panels, and modulate the transmitted light to generate image light. The image light modulated by passing through each liquid crystal panel is combined by a combining optical system such as a cross dichroic prism and emitted to the projection optical system 113.

The light modulation device 112 is driven by the light modulation device driving unit 122. The light modulator driving unit 122 is connected to the internal bus 180.
The light modulation device driving unit 122 generates R, G, and B image signals based on display image data input from an image composition unit 153 described later. The light modulator driving unit 122 drives the corresponding liquid crystal panel based on the generated R image signal, G image signal, and B image signal, and draws an image on each liquid crystal panel.

  The projection optical system 113 includes a lens group that projects the image light modulated by the light modulation device 112 toward the screen SC and forms an image on the screen SC. Further, the projection optical system 113 may include a zoom mechanism for enlarging / reducing the projected image of the screen SC and adjusting the focus, and a focus adjusting mechanism for adjusting the focus.

The projector 100 includes an operation panel 131 and an input processing unit 133. The input processing unit 133 is connected to the internal bus 180.
The operation panel 131 functioning as a user interface is provided with various operation keys and a display screen constituted by a liquid crystal panel.
When the operation key on the operation panel 131 is operated, the input processing unit 133 outputs an operation signal corresponding to the operated key to the control unit 160. In addition, the operation panel 131 is integrally formed with a touch sensor that detects contact with the operation panel 131. The input processing unit 133 detects the position of the operation panel 131 touched by the user's finger or the like as an input position, and outputs an operation signal corresponding to the detected input position to the control unit 160. Further, the input processing unit 133 causes the operation panel 131 to display various screens based on the control signal input from the control unit 160.

  Further, the projector 100 has a remote controller 5 used by the user. The remote controller 5 includes various buttons, and transmits an infrared signal corresponding to the operation of these buttons. The main body of the projector 100 is provided with a remote control light receiving unit 132 that receives an infrared signal emitted from the remote control 5. The remote control light receiving unit 132 receives an infrared signal transmitted from the remote control 5. The input processing unit 133 decodes the infrared signal received by the remote control light receiving unit 132, generates an operation signal indicating the operation content in the remote control 5, and outputs the operation signal to the control unit 160.

The projector 100 includes a GPS positioning unit 135 and a wireless communication unit 137 as a position specifying unit. The GPS positioning unit 135 and the wireless communication unit 137 are connected to the internal bus 180.
The GPS positioning unit 135 receives and analyzes GPS radio waves received by a GPS antenna (not shown), and calculates position information (latitude and longitude) of the projector 100. The GPS positioning unit 135 outputs the calculated position information to the control unit 160.
The wireless communication unit 137 includes an antenna, an RF (Radio Frequency) circuit, and the like (all not shown), and performs wireless communication with an external device under the control of the control unit 160. As a wireless communication method of the wireless communication unit 137, for example, a wireless LAN (Local Area Network), Bluetooth (registered trademark), UWB (Ultra Wide Band), a short-range wireless communication method such as infrared communication, or a mobile phone line is used. A wireless communication system can be adopted.

The projector 100 includes an indicator detection unit 140 that detects an operation with a pen-type indicator 70 and an operation position indicated by the operation. The indicator detection unit 140 includes an imaging unit 141 and a position detection unit 142. The indicator detection unit 140 is connected to the internal bus 180.
The photographing unit 141 includes a digital camera and photographs the screen SC to generate photographed image data. The photographing range of the photographing unit 141, that is, the angle of view is preferably a range including the entire screen SC or the screen SC.
The camera mounted on the imaging unit 141 is not limited to a camera that performs imaging using visible light, and may be a camera that captures infrared light. For example, the indicator 70 may be provided with a light emitting unit that emits infrared light, the light emission of the light emitting unit is imaged by the imaging unit 141, and the operation position of the indicator 70 is detected.

  The position detection unit 142 detects the operation position of the indicator 70. The position detection unit 142 analyzes the captured image data of the imaging unit 141 and detects the image of the indicator 70 from the captured image. When the position detector 142 detects the image of the indicator 70 from the captured image, the position detector 142 detects the position of the tip of the indicator 70 and specifies the coordinates of the detected operation position. The coordinates specified by the position detection unit 142 are the coordinates of the operation position of the indicator 70 in the captured image. The position detection unit 142 outputs the detected coordinates of the operation position to the control unit 160.

  The projector 100 includes an image processing system. This image processing system is configured around a control unit 160 that controls the entire projector 100 in an integrated manner. In addition to this, a storage unit 170, an image input unit 151, an image processing unit 152, an image composition unit 153, and a frame memory. 154. Each unit constituting the image processing system is connected to each other via an internal bus 180 so that data communication is possible.

The image processing unit 152 processes the image data input from the image input unit 151 under the control of the control unit 160, and outputs the processed image data to the image composition unit 153. The processing executed by the image processing unit 152 includes, for example, resolution conversion (scaling) processing or resizing processing, shape correction processing such as distortion correction, digital zoom processing, color tone correction processing, and luminance correction processing. The image processing unit 152 executes processing specified by the control unit 160 and performs processing using parameters input from the control unit 160 as necessary. Of course, the image processing unit 152 can also execute a combination of a plurality of processes.
The image data supplied from the image supply device 200 and processed by the image processing unit 152 is hereinafter referred to as first image data. The first image data corresponds to “image data supplied from the outside” of the present invention. Note that image data supplied from the outside includes image data supplied from the image supply device 200 and stored in the storage unit 170. That is, image data stored in the storage unit 170 when the power of the projector 100 is turned on is also included.

  The image composition unit 153 develops the first image data input from the image processing unit 152 in the frame memory 154. Further, the image composition unit 153 acquires image data (hereinafter referred to as second image data) generated by the control unit 160 and develops it in the frame memory 154. Here, the image synthesis unit 153 synthesizes the first image data input from the image processing unit 152 and the second image data generated by the control unit 160 in the frame memory 154. The image composition unit 153 reads the synthesized image data from the frame memory 154 and outputs it as display image data to the light modulator driving unit 122.

  The control unit 160 includes a CPU, a ROM, and a RAM (all not shown) as hardware. The ROM is a non-volatile storage device such as a flash ROM, and stores a control program and data. The ROM stores registered position information. The registered position information is stored in the storage unit 170 by encrypting data (content data to be described later, for example, confidential information such as a moving image or a still image as a conference material or a memo written by a conference participant). In this case, it is information for determining whether to permit data decoding and to permit copying and reproduction of data. That is, when the projector 100 is at a position set in advance as registered position information, data decoding is permitted. When the projector 100 is at a position other than the position set in advance, data decoding is restricted. . In addition, the “position” set in advance includes both the case of indicating one point and the case of indicating a predetermined range. For example, when the position of the projector 100 is specified by position information measured by the GPS positioning unit 135 and “position” indicates one point, the current position of the projector 100 measured by the GPS positioning unit 135 is determined in advance. It is determined whether or not it matches the set position. If the “position” indicates a predetermined range, it is determined whether or not the current position of the projector 100 measured by the GPS positioning unit 135 is within a preset range from a preset position. Is done. The predetermined range is, for example, a preset range such as a conference room, one floor, or a company. The RAM constitutes a work area of the CPU. The CPU expands the control program and data read from the ROM to the RAM, and executes the expanded control program to control each unit of the projector 100.

  The control unit 160 includes a projection control unit 161, an operation acquisition unit 162, a drawing processing unit 163, a data storage unit 164, an encryption processing unit 165, and a decryption processing unit 167 as functional blocks. These functional blocks are realized by executing a control program expanded in the RAM. The drawing processing unit 163 corresponds to the generation unit of the present invention, and the encryption processing unit 165 corresponds to the determination unit, the decryption control unit, and the encryption unit of the present invention. The decoding processing unit 167 corresponds to the processing unit of the present invention.

The projection control unit 161 controls each unit of the projector 100 to control the projection of the image onto the screen SC.
Specifically, the projection control unit 161 controls the image processing unit 152 to perform image processing on the image data supplied from the image supply device 200. At this time, the projection control unit 161 may read parameters necessary for processing by the image processing unit 152 from the storage unit 170 and output the parameters to the image processing unit 152. In addition, the projection control unit 161 controls the image combining unit 153 to execute processing for combining the first image data and the second image data, and controls the light modulation device driving unit 122 to control the light modulation device. An image is drawn on the liquid crystal panel 112. Further, the projection control unit 161 controls the light source driving unit 121 to turn on the light source of the light source unit 111 and adjust the luminance of the light source. As a result, the light source emits light and the image light modulated by the light modulation device 112 is projected onto the screen SC by the projection optical system 113.

  The operation acquisition unit 162 acquires the operation position detected by the pointer detection unit 140. The operation position detected by the pointer detection unit 140 is input to the control unit 160 as coordinates in the captured image. The operation acquisition unit 162 converts the coordinates input from the indicator detection unit 140 into coordinates for the drawing processing unit 163 to perform drawing. The operation acquisition unit 162 converts the coordinates input from the indicator detection unit 140 into coordinates in the frame memory 154.

  The drawing processing unit 163 performs a process of drawing characters, symbols, and figures in accordance with the operation position detected by the indicator detection unit 140 or the locus of the operation position. The drawing processing unit 163 generates second image data that is data of characters, symbols, and figures such as kanji, hiragana, katakana, alphabets, and numbers in accordance with the size of the first image data developed in the frame memory 154. To do. The second image data corresponds to “image data corresponding to the operation” of the present invention. The second image data generated by the drawing processing unit 163 is output to the image composition unit 153. The image composition unit 153 superimposes and expands the image based on the second image data generated by the drawing processing unit 163 on the frame memory 154 in which the image based on the first image data processed by the image processing unit 152 is expanded. And synthesize.

When the operation panel 131 or the remote controller 5 is operated and an input for instructing data storage is received, the data storage unit 164 creates a file for storing image data in the storage unit 170. Each time at least one of the first image data and the second image data developed in the frame memory 154 is changed, the data storage unit 164 receives the first image data and the second image data from the image composition unit 153 or the first image data. Either image data or second image data is acquired. Then, the data storage unit 164 stores the acquired image data (at least one of the first image data and the second image data) in the file of the storage unit 170 as content data.
Further, when storing the content data in the file, the data storage unit 164 may attach time information indicating the time when the content data is stored in the file, a serial number that can identify the content data, or the like to the content data. .
In addition, the data storage unit 164 acquires image data from the image composition unit 153 every elapse of a predetermined time without determining whether the image data (first image data and second image data) has been changed. You may save to a file.

The encryption processing unit 165 registers registration position information indicating a position where the use of content data is permitted (hereinafter referred to as a permitted position). For “use” of content data, projection on the screen SC by the display unit 110, other devices (for example, a personal computer, a USB memory, etc.) connected to the projector 100, and decrypted content data itself or a copy thereof Are transferred to other devices for storage. Moreover, transmitting the content data decoded by the wireless communication by the wireless communication part 137 or the wired communication via a communication cable to another apparatus (for example, personal computer) is included.
For example, when a button on the operation panel 131 or the remote controller 5 is operated and the projector 100 is set to the initial setting mode, the encryption processing unit 165 permits the current position where the projector 100 is installed on the operation panel 131. A message for inquiring whether to register as a position is displayed. When an operation for registering the current position as a permitted position is input, the encryption processing unit 165 causes the GPS positioning unit 135 to determine the current position of the projector 100 and position information (latitude and longitude information) as a positioning result. To get. The encryption processing unit 165 stores the acquired latitude and longitude information in the ROM as registered position information.
When the encryption processing unit 165 receives an input indicating that the current position is not registered as the permitted position, the encryption processing unit 165 displays “Please move the projector 100 to a position where you want to register as the permitted position” on the operation panel 131. Display the message. Then, the encryption processing unit 165 waits until an input for registration as a permitted position is received. When the input for registration is received, the encryption processing unit 165 causes the GPS positioning unit 135 to determine the current position of the projector 100, and the position as a positioning result. Information is stored in ROM.

The position information stored in the ROM as registered position information may be only one or plural. For example, when the projector 100 is used in a plurality of conference rooms, registration of a plurality of registered position information may be permitted.
The registered position information registered in the ROM may be changed by an operation of a user having administrator authority. For example, the storage unit 170 stores a user ID and password as authentication information, and the encryption processing unit 165 authenticates a user having administrator authority using these authentication information. When the user authentication is successful, the encryption processing unit 165 displays a message such as “Move the projector 100 to a position to be registered as a permitted position” on the operation panel 131. Then, the encryption processing unit 165 waits until an input for registration as a permitted position is received. When the input for registration is received, the encryption processing unit 165 causes the GPS positioning unit 135 to determine the current position of the projector 100, and the position as a positioning result. Information is stored in ROM.

The registered position information is used for encryption of a file stored in the storage unit 170. When the data protection function is turned on, the encryption processing unit 165 encrypts all the files stored in the storage unit 170 with the encryption key based on the registered position information stored in the ROM, and stores the encrypted files in the storage unit Store in 170.
The data protection function is a function that encrypts all files stored in the storage unit 170 and permits decryption of files only at a position (permitted position) set in advance as registered position information.

In addition, the encryption processing unit 165 includes a random number generation unit 166.
When the operation panel 131 or the remote controller 5 is operated and an input requesting decryption of a file is received, or when the projector 100 is activated after the power is turned on, the encryption processing unit 165 sends the projector to the GPS positioning unit 135. The current position of 100 is measured. When the position measured by the GPS positioning unit 135 is not in the permitted position, the encryption processing unit 165 restricts the decryption of the file. In this case, the encryption processing unit 165 does not instruct the decryption processing unit 167 to decrypt the file. In addition, the encryption processing unit 165 causes the random number generation unit 166 to generate a random number. It is assumed that the random number generated by the random number generation unit 166 is a random number with a random number of digits. The encryption processing unit 165 encrypts all files stored in the storage unit 170 using the random number generated by the random number generation unit 166 as an encryption key (a key that cannot be decrypted). An encrypted file is a file that cannot be decrypted.
Whether or not the current position of the projector 100 is at the permitted position is determined in advance by setting the position measured by the GPS positioning unit 135 as the current position of the projector 100 from the position registered as the registered position information. It is determined by whether or not it is within the range. When the position measured by the GPS positioning unit 135 is within the range set in advance from the position registered as the registered position information, the projector 100 is determined to be in the permitted position.
Also, the encryption processing unit 165 determines whether or not the position measured by the GPS positioning unit 135 matches the position registered as registered position information, and whether or not the projector 100 is in the permitted position. May be determined.

When the position of the projector 100 is not in a preset position, the method of preventing the projector 100 from leaking the file to the outside is not limited to the method of encrypting the file with the random number generated by the random number generation unit 166. .
For example, when the position of the projector 100 is not in a preset position, the file may be encrypted with a new encryption key generated by the encryption processing unit 165 or acquired from the outside. After encrypting the file, the encryption processing unit 165 discards the encryption key used for encryption without storing it in the ROM, the storage unit 170, or the like. This prevents the decryption processing unit 167 described later from decrypting the encrypted file.
Further, the position information is not limited to the positioning information of the GPS positioning unit 135. For example, position information acquired from a base station constituting a mobile communication network, information for specifying a communication area covered by the base station, identification information of a base station with which the projector 100 communicates, and the like can be used as position information. Further, the position and area of the projector 100 (for example, a conference) specified by using received signal strength information corresponding to the distance from the access point of the wireless LAN, access point information (SSID, password, access point ID), or the like. Room etc.) can also be used as position information.

When the decryption processing unit 167 is instructed to decrypt the file by the encryption processing unit 165, the decryption processing unit 167 decrypts the file designated by the operation of the operation panel 131 or the remote controller 5. The decryption processing unit 167 decrypts the file with the decryption key based on the registered position information.
The registered location information registered in the ROM is used as an encryption key for encrypting the file and a decryption key for decrypting the encrypted file.
The encryption processing unit 165 and the decryption processing unit 167 generate a key by combining the hour, minute, and second numbers indicating the east longitude and the hour, minute, and second numbers indicating the north latitude in the registered position information. The file is encrypted using the key, and the encrypted file is decrypted. The encryption key used for file encryption and the decryption key used for decryption may be the same key (that is, a key generated by a common key encryption method), or may be different keys. .

  The storage unit 170 is a non-volatile storage device configured by a semiconductor memory element, and is realized by a storage device such as a flash memory, an EPROM (Erasable Programmable ROM), or an EEPROM (Electrically EPROM), for example. Further, the storage unit 170 stores a file generated by the data storage unit 164 of the control unit 160. Content data is stored in the file by the data storage unit 164. When the data protection function is turned on, all files stored in the storage unit 170 are encrypted.

FIG. 2 is a flowchart showing a process flow of the control unit 160.
First, the control unit 160 determines whether or not the user has operated the operation panel 131 or the remote controller 5 to accept an input (step S1). When the input is not received (step S1 / NO), the control unit 160 repeats the determination in step S1. In addition, when receiving an input (step S1 / YES), the control unit 160 determines whether or not the received input is an input for setting the data protection function on (step S2).

  When the input is not an input for setting the data protection function to ON (step S2 / NO), the control unit 160 performs processing corresponding to the received input (step S3). When the input is an input for setting the data protection function to ON (step S2 / YES), the control unit 160 encrypts all the files stored in the storage unit 170 by the processing of the encryption processing unit 165. (Step S4). The encryption processing unit 165 encrypts the content data stored in the storage unit 170 for each file with an encryption key generated based on the registered position information stored in the ROM.

  Next, the control unit 160 determines whether or not the operation panel 131 or the remote controller 5 has been operated to accept an input (step S5). When the input is not received (step S5 / NO), the control unit 160 repeats the determination of step S5. Further, when receiving an input (step S5 / YES), the control unit 160 determines whether or not the received input is an input for instructing data storage (step S6). If the input is not an instruction to store data (step S6 / NO), the control unit 160 proceeds to the determination of step S10. Details of this determination will be described later.

When the control unit 160 receives an input for instructing data storage (step S6 / YES), the data storage unit 164 creates a file for storing content data in the storage unit 170 (step S7), and the file of the created file is stored. Accept name input. When the input of the file name is accepted and at least one of the first image data and the second image data is expanded in the frame memory 154, the data storage unit 164 receives the first image data and the second image data from the image composition unit 153. At least one of them is acquired and stored in a file created as content data (step S7).
Further, the data storage unit 164 receives the first image data and the second image data from the image composition unit 153 each time at least one of the first image data and the second image data developed in the frame memory 154 is changed. One of the first image data and the second image data is acquired. Then, the data storage unit 164 stores the acquired image data (at least one of the first image data and the second image data) as content data in a file in the storage unit 170 (step S7). When storing the content data in a file, the data storage unit 164 may store the content data by adding additional information such as the storage time of the content data.

  Next, the data storage unit 164 determines whether or not an input for ending data storage has been received by operating the operation panel 131 or the remote controller 5 (step S8). When the data storage unit 164 has not received an input for ending data storage (step S8 / NO), the data storage unit 164 repeats the process of step S7 every time at least one of the first image data and the second image data is changed. If an input for ending data storage is received (step S8 / YES), the control unit 160 encrypts the file storing the content data by the encryption processing unit 165 and stores the encrypted file in the storage unit 170 (step S8). S9). The encryption processing unit 165 reads the registered position information from the ROM, and encrypts the file storing the content data with the encryption key generated based on the read registered position information. When the control unit 160 encrypts the file and stores it in the storage unit 170, the control unit 160 returns to the determination in step S5 and determines whether or not an input has been accepted.

FIG. 3 is a flowchart showing a continuation of FIG.
When the determination in step S6 is negative (step S6 / NO), control unit 160 determines whether or not the accepted input is a data acquisition request (step S10). When it is determined that the accepted input is a data acquisition request (step S10 / YES), the encryption processing unit 165 of the control unit 160 outputs a position information acquisition request to the GPS positioning unit 135 (step S11). The position information acquired from the GPS positioning unit 135 is hereinafter referred to as positioning information. When the positioning information is acquired from the GPS positioning unit 135, the encryption processing unit 165 reads the registered position information from the ROM, and the position indicated by the positioning information acquired from the GPS positioning unit 135 is set in advance from the position indicated by the registered position information. It is determined whether or not it is within the range (step S12). When the position indicated by the positioning information is not within the preset range from the position indicated by the registered position information (step S12 / NO), the encryption processing unit 165 causes the random number generation unit 166 to generate a random number, A random number encryption key is generated (step S14). The control unit 160 encrypts all the files stored in the storage unit 170 with the generated encryption key, and performs processing so that the data cannot be decrypted (step S15).

  If the encryption processing unit 165 determines that the position indicated by the positioning information is within a preset range from the position indicated by the registered position information (step S12 / YES), the encryption processing unit 165 stores the file in the decryption processing unit 167. Is instructed to decrypt. The decryption processing unit 167 decrypts the file having the file name designated by the operation of the operation panel 131 or the remote controller 5 using the decryption key generated based on the registered position information acquired from the ROM (step S13).

  If it is determined in step S10 that the received input is not a data acquisition request (step S10 / NO), the control unit 160 determines whether the received input is an input for turning off the data protection function. Is determined (step S16). When the input is to turn off the data protection function (step S16 / YES), the control unit 160 uses the decryption processing unit 167 to generate all the files stored in the storage unit 170 based on the registered location information. To complete the process (step S17).

When the received input is not an input for turning off the data protection function (step S16 / NO), the control unit 160 determines whether or not the received input is an input for turning off the power of the projector 100. (Step S18). When the received input is an input for turning off the power (step S18 / YES), the data storage unit 164 determines whether there is unsaved content data (step S19). When it is determined that there is unsaved content data (step S19 / YES), the data storage unit 164 stores the unsaved content data in a file, and the encryption processing unit 165 stores the file in which the content data is stored. Encryption is performed using an encryption key generated based on the registered position information (step S20). Then, the control unit 160 turns off the power of the projector 100. When it is determined that there is no unsaved content data (step S19 / NO), the control unit 160 turns off the power of the projector 100.
When the received input is not an input for turning off the power of the projector 100 (step S18 / NO), the control unit 160 performs processing corresponding to the received input (step S21), and returns to the determination of step S5. To determine whether an input has been accepted.

FIG. 4 is a flowchart illustrating a processing flow when the power of the projector 100 is turned on and the control unit 160 is activated.
When the projector 100 is turned on and activated (step S31 / YES), the encryption processing unit 165 outputs a positioning information acquisition request to the GPS positioning unit 135 and acquires the positioning information from the GPS positioning unit 135 ( Step S32). Next, the encryption processing unit 165 reads the registered position information from the ROM, and determines whether or not the position indicated by the positioning information acquired from the GPS positioning unit 135 is within a preset range from the position indicated by the registered position information. Is determined (step S33). When the position indicated by the positioning information is within the range set in advance from the position indicated by the registered position information (step S33 / YES), the process proceeds to the determination of step S5 shown in FIG. Further, when the position indicated by the positioning information is not within the range set in advance from the position indicated by the registered position information (step S33 / NO), the encryption processing unit 165 generates a random number in the random number generation unit 166. To generate a random number encryption key (step S34). The encryption processing unit 165 encrypts all the files stored in the storage unit 170 with the generated encryption key, and performs processing so that the data cannot be decrypted (step S35).

  In the above-described flowchart, it is determined whether the position indicated by the positioning information measured by the GPS positioning unit 135 is within a preset range from the position indicated by the registered position information, and the storage unit 170 stores the position. Judged whether to decrypt the file. As another determination method, the encryption processing unit 165 determines whether the position indicated by the registered position information matches the position indicated by the positioning information acquired from the GPS positioning unit 135, and stores the data in the storage unit 170. It may be determined whether or not the file to be decrypted is to be decrypted.

  As described above in detail, the projector 100 according to the present embodiment includes the encryption processing unit 165 that determines whether the position specified by the GPS positioning unit 135 is a position set in advance. The encryption processing unit 165 limits the decryption of the data stored in the storage unit 170 when it is determined that the specified position is not a position set in advance. Therefore, the safety of data stored in the projector 100 can be improved and information leakage can be prevented.

  The projector 100 also displays a display unit 110 that displays an image based on image data supplied from the image supply device 200 as an external device (external), and an indicator 70 to the screen SC on which the image is displayed by the display unit 110. A pointer detection unit 140 that detects an operation by the pointer, and a drawing processing unit 163 that generates image data corresponding to the operation detected by the pointer detection unit 140. The encryption processing unit 165 obtains at least one of the image data (first image data) supplied from the image supply device 200 and the image data (second image data) corresponding to the operation generated by the drawing processing unit 163. The data is encrypted and stored in the storage unit 170. Therefore, at least one of the image data whose image is displayed on the screen SC and the image data corresponding to the operation can be encrypted and stored in the storage unit 170.

  In addition, the encryption processing unit 165 includes at least image data (first image data) supplied from the image supply device 200 and image data (second image data) corresponding to the operation generated by the drawing processing unit 163. One is encrypted with an encryption key based on the position information specified by the GPS positioning unit 135. Therefore, even if the projector 100 is stolen or data is copied from the storage unit 170 and distributed, it is impossible to decode at a position other than the preset position. For this reason, it is possible to limit browsing of data at a position other than the position set in advance.

  Also, the encryption processing unit 165 decrypts the data stored in the storage unit 170 when it is determined that the position specified by the GPS positioning unit 135 is a preset position. Therefore, data can be decoded when the position of the projector 100 is a preset position.

  Also, the encryption processing unit 165 decrypts the data encrypted with the encryption key based on the position information specified by the GPS positioning unit 135, with the decryption key based on the position information. Therefore, the encrypted data can be decrypted only at a preset position, and decryption can be restricted at other positions.

  In addition, the encryption processing unit 165, when it is determined that the position specified by the GPS positioning unit 135 is not the position set in advance, the data stored in the storage unit 170 using a key that cannot be decrypted. Encrypt further. Therefore, even if data is transferred to a third party by unauthorized duplication, loss, theft, etc., it is possible to make it impossible to view the data and further improve the safety of information.

  The storage unit 170 is configured by a semiconductor memory element. When it is determined that the position specified by the GPS positioning unit 135 is not a preset position, the encryption processing unit 165 performs a writing process for the storage unit 170 more than the preset number of times. Run. Therefore, even if data is transferred to a third party by unauthorized duplication, loss, theft, etc., it is possible to make it impossible to view the data and further improve the safety of information.

  Also, the encryption processing unit 165 determines whether or not the position specified by the GPS positioning unit 135 is a preset position when the projector 100 is activated. Therefore, even if the projector 100 is stolen by a third party and activated at a position other than a preset position, data browsing can be restricted.

  In addition, when the position specified by the GPS positioning unit 135 is within a preset range, the encryption processing unit 165 determines that the specified position is in a preset position. Therefore, the projector 100 can be used within a preset range.

The above-described embodiment shows a preferred embodiment of the present invention, does not limit the present invention, and various modifications can be made without departing from the gist of the present invention.
For example, in the above-described embodiment, when the position indicated by the positioning information is not within a preset range from the position indicated by the registered position information, the encryption processing unit 165 encrypts the data with a key that cannot be decrypted, Prevented data from being viewed by third parties. As another countermeasure for preventing the data stored in the storage unit 170 from being viewed by a third party, the encryption processing unit 165 has set the data exceeding the rewritable number of times set in advance in the storage unit 170 with respect to the storage unit 170. Writing may be performed to prevent data from being viewed by a third party. When the storage unit 170 is configured by a storage device composed of semiconductor memory elements such as flash memory, EPROM, and EEPROM, the encryption processing unit 165 stores data in the storage unit 170 more than the preset number of rewritable times. The writing and storage unit 170 may not be able to maintain data, or the data stored in the storage unit 170 may be destroyed.

  Further, in the above-described embodiment, the content data is further encrypted with the generated random number at a position other than the preset position, but the projector 100 is prevented from being turned on after the content data is encrypted. May be.

  Further, the projector 100 has been described by taking the configuration in which the pointer detection unit 140 is built in as an example, but the present invention is not limited to this, and the pointer detection unit 140 may be externally connected to the projector 100. Good. For example, a position detection device having the function of the indicator detection unit 140 may be connected to each projector 100 and used.

  The display device of the present invention has been described as a liquid crystal projector using a transmissive liquid crystal panel, but may be a projector using a reflective liquid crystal panel or a digital mirror device. Further, the projector is not limited to a projector that projects an image on the screen SC, but a liquid crystal monitor or liquid crystal television that displays an image on a liquid crystal display panel, or a monitor device or television receiver that displays an image on a plasma display panel (PDP), OLED Various display devices such as a monitor device that displays an image on an organic EL display panel called (Organic light-emitting diode), OEL (Organic Electro-Luminescence), or a self-luminous display device such as a television receiver are also included in the present invention. It is included in the display device.

  Each functional unit of the projector 100 illustrated in FIG. 1 indicates a functional configuration realized by cooperation of hardware and software, and a specific mounting form is not particularly limited. Therefore, it is not always necessary to mount hardware corresponding to each function unit individually, and it is of course possible to realize a function of a plurality of function units by one processor executing a program. In addition, in the above embodiment, a part of the function realized by software may be realized by hardware, or a part of the function realized by hardware may be realized by software.

DESCRIPTION OF SYMBOLS 70 ... Indicator, 100 ... Projector (display device), 110 ... Display unit, 135 ... GPS positioning unit (position specifying unit), 140 ... Indicator detection unit (detection unit), 141 ... Shooting unit, 142 ... Position detection unit , 151 ... Image input unit, 152 ... Image processing unit, 153 ... Image composition unit, 154 ... Frame memory, 160 ... Control unit, 161 ... Projection control unit, 162 ... Operation acquisition unit, 163 ... Drawing processing unit (generation unit) 164 ... Data storage unit, 165 ... Encryption processing unit (encryption unit, determination unit, decryption control unit), 166 ... Random number generation unit, 167 ... Decryption processing unit (processing unit), 170 ... Storage unit, 200 ... Image Feeder, SC ... screen.

Claims (10)

A display device that displays an image based on image data,
A storage unit for storing the encrypted data;
A position specifying unit for specifying the position of the display device;
A determination unit that determines whether or not the position specified by the position specifying unit is a position set in advance;
A decoding control unit that restricts decoding of the data stored in the storage unit when the determination unit determines that the position is not the preset position;
A display device comprising: A display unit for displaying an image based on image data supplied from the outside;
A detection unit for detecting an operation by an indicator on the display surface on which the image is displayed by the display unit;
A generation unit that generates image data corresponding to the operation detected by the detection unit;
An encryption unit that encrypts at least one of the image data supplied from the outside and image data corresponding to the operation generated by the generation unit, and stores the encrypted image data in the storage unit;
The display device according to claim 1, further comprising:   The encryption unit encrypts at least one of the image data supplied from the outside and the image data corresponding to the operation generated by the generation unit based on the position information specified by the position specifying unit. The display device according to claim 2, wherein encryption is performed using a key.   A processing unit that decodes the data stored in the storage unit when the position specified by the position specifying unit is determined to be the position set in advance by the determination unit; The display device according to claim 1, wherein:   5. The processing unit according to claim 4, wherein the processing unit decrypts the data encrypted with an encryption key based on the position information specified by the position specifying unit, with a decryption key based on the position information. Display device.   The encryption unit further encrypts the data stored in the storage unit when it is determined that the position specified by the position specifying unit is not the position set in advance by the determination unit. The display device according to claim 2, characterized in that: The storage unit is constituted by a semiconductor memory element,
The decoding control unit is set in advance for the semiconductor memory element when it is determined that the position specified by the position specifying unit is not the position set in advance by the determination unit. The display device according to claim 1, wherein the writing process is executed more than the number of times.   The said determination part determines whether the said position specified by the said position specific | specification part is the said preset position at the time of starting of the said display apparatus. The display apparatus in any one of.   The determination unit determines that the specified position is in the preset position when the position specified by the position specifying unit is within a preset range. The display device according to claim 1, wherein: A data protection method for a display device that displays an image based on image data,
A specifying step of specifying the position of the display device;
A determination step of determining whether or not the position specified by the specifying step is a position set in advance;
A limiting step of limiting the decryption of the data stored in the storage unit that stores the encrypted data when it is determined by the determination step that the position is not set in advance;
A data protection method for a display device, comprising:

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