The present invention provides a photographing synchronization method for performing a synchronous photographing operation on a plurality of cameras using any one of cameras in a multi-camera system. The method comprises: obtaining all cameras in a current synchronous network by means of network broadcast; obtaining signal transmission delays between the cameras; generating a synchronous photographing instruction of each camera according to the signal transmission delays between the cameras; and sending the synchronous photographing instructions to particular cameras over a wireless network.

A radiation imaging apparatus includes: a detection unit configured to detect emitted radiation and output radiation image data; a clock control unit that has an internal clock and is configured to control a timing at which the detection unit is driven, based on time information of the internal clock; and a communication unit configured to transmit and receive data through a network, wherein the communication unit, if a communication traffic of the radiation image data is at a threshold or less, transmits the time information to a control apparatus that is connected through the network, and the clock control unit corrects the time information of the internal clock using time information that is a reply from the control apparatus to the time information.

A radiation imaging apparatus includes: a detection unit configured to detect emitted radiation and output radiation image data; a clock control unit that has an internal clock and is configured to control a timing at which the detection unit is driven, based on time information of the internal clock; and a communication unit configured to transmit and receive data through a network, wherein the communication unit, if a communication traffic of the radiation image data is at a threshold or less, transmits the time information to a control apparatus that is connected through the network, and the clock control unit corrects the time information of the internal clock using time information that is a reply from the control apparatus to the time information.

An imaging system includes first and second light source devices configured to irradiate a subject with lights having different wavelength bands, first and second imaging devices configured to image the subject, and first and second video processing devices configured to process an imaged video of the subject imaged by either of the corresponding imaging devices and to output the processed video to an output unit. The first and second light source devices alternately perform lighting in synchronization with a frame period of the imaged video or an integer multiple thereof based on a genlock signal. The first imaging device performs imaging in synchronization with the lighting of each of the first and second light source devices. The second imaging device performs imaging in synchronization with the lighting of each of the first and second light source devices.

A control device includes a data storing unit, a synchronization control unit, and a duty control unit. The synchronization control unit starts a frame period when a vertical synchronization signal is received. The frame period includes a video image period and an extended period. The synchronization control unit initializes pixel circuits within a predetermined period after the reception of the vertical synchronization signal, temporarily stores the video image signal in the data storing unit after the reception of the vertical synchronization signal, and supplies the video image signal from the data storing unit to a display panel after the initialization and during the video image period. The duty control unit causes the display panel to emit light after the initialization and during the video image period, and controls the display panel such that the display panel emits and extinguishes light at a predetermined duty ratio during the extended period.

A control device includes a data storing unit, a synchronization control unit, and a duty control unit. The synchronization control unit starts a frame period when a vertical synchronization signal is received. The frame period includes a video image period and an extended period. The synchronization control unit initializes pixel circuits within a predetermined period after the reception of the vertical synchronization signal, temporarily stores the video image signal in the data storing unit after the reception of the vertical synchronization signal, and supplies the video image signal from the data storing unit to a display panel after the initialization and during the video image period. The duty control unit causes the display panel to emit light after the initialization and during the video image period, and controls the display panel such that the display panel emits and extinguishes light at a predetermined duty ratio during the extended period.

A display driver circuit includes a source driver configured to output display data to data lines, a controller configured to control the source driver, based on a synchronization signal, and a frequency adjusting circuit configured to extend a first time interval of the synchronization signal from a first length to a second length, such that time interval in which the display data is not output to the data lines is extended, when second image data are not received from an external device during a reference time interval after first image data are received from the external device, and shorten the first time interval, from the second length to a third length, when an instruction is received from the external device after the first time interval is extended to the second length.

A display driver circuit includes a source driver configured to output display data to data lines, a controller configured to control the source driver, based on a synchronization signal, and a frequency adjusting circuit configured to extend a first time interval of the synchronization signal from a first length to a second length, such that time interval in which the display data is not output to the data lines is extended, when second image data are not received from an external device during a reference time interval after first image data are received from the external device, and shorten the first time interval, from the second length to a third length, when an instruction is received from the external device after the first time interval is extended to the second length.

A method for driving a display panel displays a video image signal that includes a plurality of images having different frame periods. The method includes setting a frame period including one or more light emission periods, and one or more light extinction periods. The method also includes dividing at least one frame period into a plurality of light emission periods and a plurality of light extinction periods, and adjusting lengths of the plurality of light emission periods and lengths of the plurality of light extinction periods based on a ratio between a maximum frequency of the frame period and a currently set frequency of the frame period. The method further includes displaying the video image signal by causing light emitting elements of the display panel to emit light during the adjusted light emission periods, and to extinguish light during the adjusted light extinction periods.

A method for driving a display panel displays a video image signal that includes a plurality of images having different frame periods. The method includes setting a frame period including one or more light emission periods, and one or more light extinction periods. The method also includes dividing at least one frame period into a plurality of light emission periods and a plurality of light extinction periods, and adjusting lengths of the plurality of light emission periods and lengths of the plurality of light extinction periods based on a ratio between a maximum frequency of the frame period and a currently set frequency of the frame period. The method further includes displaying the video image signal by causing light emitting elements of the display panel to emit light during the adjusted light emission periods, and to extinguish light during the adjusted light extinction periods.