JP5745836B2 - Display device - Google Patents

Description

  The present invention relates to a display device and the like. In particular, the present invention relates to a display device that uses a plurality of backlights that generate light transmitted through a liquid crystal panel and adjusts the amount of light emission for each backlight.

  As a device for displaying an image, a display device using a liquid crystal panel is known. In such a display device, a backlight that generates light that passes through the liquid crystal panel is used, and an image is displayed by adjusting the light transmittance for each pixel of the liquid crystal panel. However, in the case of using liquid crystal, it is difficult to completely block light, so that it is difficult to increase the contrast of an image.

  Therefore, local dimming is known as a technique for dividing the backlight region into a plurality of regions, adjusting the light emission amount for each region, and increasing the contrast of the video (see, for example, Patent Document 1).

JP 2009-294637 A

  In recent years, large liquid crystal panels have been manufactured, and the number of pixels of a single liquid crystal panel has increased dramatically, and higher resolution has been promoted. For this reason, the operating frequency of the drive circuit of the liquid crystal panel is increasing. However, it is difficult to design a drive circuit that operates at a high frequency, and the manufacturing cost of the display device tends to increase.

  An embodiment of the present invention includes a liquid crystal panel having a plurality of liquid crystal pixels, a plurality of data driving units, and a plurality of timing controllers, wherein the plurality of liquid crystal pixels belong to any of a plurality of blocks, and Each of the data driving units corresponds to one of the plurality of blocks and controls the light transmittance of the liquid crystal pixels belonging to the block, and each of the plurality of timing controllers includes one of the plurality of data driving units. The display device is characterized in that the corresponding data driver outputs control data for controlling the light transmittance of the liquid crystal pixels belonging to the corresponding block to the corresponding data driver. To do.

  The display device according to an embodiment of the present invention further includes a plurality of backlight units, and each of the plurality of backlight units transmits a liquid crystal pixel controlled by any of the plurality of data driving units. Each of the plurality of timing controllers compensates for the light transmittance of the liquid crystal pixels according to the light emission level of the luminance distribution extraction unit that extracts the luminance distribution information of the partial image and the backlight unit. A plurality of timing controllers including a master timing controller and a slave timing controller, and the master timing controller includes luminance distribution information extracted by a luminance distribution information extraction unit of the plurality of timing controllers. Based on the light emission level of each of the plurality of backlight units. It may put.

  In the display device according to an embodiment of the present invention, the master timing controller transmits a request for luminance distribution information to the slave timing controller, and if there is no response of luminance distribution information within a predetermined time, the slave timing controller The timing controller may set the light emission level of the backlight unit for transmitting the liquid crystal pixels controlled by the corresponding data driver to the maximum level.

  In the display device according to an embodiment of the present invention, the master timing controller may return a checksum error to the acquired luminance distribution information in response to the transmission of the luminance distribution information request to the slave timing controller. For example, the light emission level of each of the plurality of backlight units may be calculated based on luminance distribution information previously acquired from the slave timing controller.

  In the display device according to the embodiment of the invention, the master timing controller may change the light emission level of each of the plurality of backlight units smoothly in time.

  Further, as an embodiment of the present invention, a liquid crystal panel having a plurality of liquid crystal pixels belonging to any of a plurality of blocks, a plurality of data driving units, and a plurality of timing controllers are provided, and each of the plurality of data driving units is Each of the plurality of timing controllers is a display device control method corresponding to any of the plurality of data driving units, wherein the plurality of data driving units correspond to any one of the plurality of blocks. Each controls the light transmittance of the liquid crystal pixels belonging to the corresponding block, and each of the plurality of timing controllers acquires the data of the partial image displayed in the corresponding block by the corresponding data driver. Control data for controlling the light transmittance of the liquid crystal pixels belonging to the corresponding block by the corresponding data driver. The and outputting the corresponding data driver, a control method of a display device.

  According to the present invention, an increase in the operating frequency of the drive circuit can be prevented even when the number of pixels of one liquid crystal panel is increased. In addition, even if an error occurs during the display process, it is possible to reduce the occurrence of an uncomfortable feeling in the display.

The functional block diagram of the display apparatus which concerns on one Embodiment of this invention Functional block diagram of a master timing controller according to an embodiment of the present invention Functional block diagram of a slave timing controller according to an embodiment of the present invention Timing chart of processing and communication in a master timing controller according to an embodiment of the present invention and a slave timing controller according to an embodiment of the present invention The flowchart of the process of the master timing controller which concerns on one Embodiment of this invention The flowchart of the process of the slave timing controller which concerns on one Embodiment of this invention A graph showing an example of a change in the light emission level when the light emission level gradually reaches the maximum level

  Below, the form for implementing this invention is demonstrated. It should be noted that the present invention should not be construed as being limited to the following description, and can be implemented even if various modifications are made to the following description.

  FIG. 1 is a functional block diagram of a display device according to an embodiment of the present invention. In FIG. 1, the display device includes a distributor 101, a master timing controller 102, two slave timing controllers 103 and 104, three data drivers 105, 106, and 107, a gate driver 108, and a liquid crystal panel. 109, a backlight control unit 110, and three backlight units 111, 112, and 113.

  The liquid crystal panel 109 corresponds to the intersection of the gate lines G1, G2,..., Gn driven by the gate driver 108 and the data lines D1, D2,..., Dm driven by the respective data drivers 105, 106, 107. In addition, a switching transistor (for example, a thin film transistor), a liquid crystal pixel Clc, and a storage capacitor Cst are provided. A set of switching transistors, liquid crystal pixels ClC, and storage capacitors Cst are arranged in a matrix. The gate electrode of the switching transistor is connected to one of the gate lines, and when the switching transistor is turned on by the potential of the gate line, the potential applied to one of the data lines is applied to the liquid crystal pixel Clc and the storage capacitor Cst. The amount of light transmitted through the liquid crystal pixel is controlled by controlling the polarization direction of the light transmitted through the liquid crystal pixel Clc. Thereby, an image is generated and displayed.

  Light that passes through each liquid crystal pixel Clc is generated by each of the plurality of backlight units 111, 112, and 113. For this reason, each backlight unit has a light source and generates uniform light to the liquid crystal pixels in the corresponding region. For example, each backlight unit has a light source such as one or a plurality of cold cathode tubes and a plurality of light emitting diodes (LEDs). Between the light source and the liquid crystal, a light guide plate and a light diffusing sheet for generating uniform light are arranged for each liquid crystal pixel.

  In one embodiment of the present invention, the liquid crystal panel 109 is divided into a plurality of regions, and each of the plurality of regions corresponds to one of the backlight units. For example, the backlight unit 111 corresponds to a region to which a liquid crystal pixel connected to the h data lines of the data lines D1 to Dh via a switching transistor belongs, and (i−h + 1) lines from the data lines Dh + 1 to Di. The backlight unit 112 corresponds to a region to which the liquid crystal pixel connected to the data line via the switching transistor belongs, and is connected to the (m−i + 1) data lines from the data line Di to Dm via the switching transistor. The backlight unit 113 corresponds to a region to which the liquid crystal pixels to be assigned belong. Thereby, the light which permeate | transmits the liquid crystal pixel of each area | region can be mainly produced | generated by the backlight part corresponding to each area | region.

  For example, a light guide plate into which light generated by the backlight unit 111 is introduced is disposed on the back surface of the region to which the liquid crystal pixels connected to the h data lines from the data lines D1 to Dh via the switching transistor are located. A light guide plate into which light generated by the backlight unit 112 is introduced is disposed in a region to which a liquid crystal pixel connected to (i−h + 1) data lines from the data lines Dh + 1 to Di via switching transistors, A light guide plate into which light generated by the backlight unit 113 is introduced is disposed on the back surface of the region to which the liquid crystal pixels connected to the (m−i + 1) data lines from the data lines Di to Dm via switching transistors. can do. As a result, light transmitted through the region of the liquid crystal pixel connected to the h data lines D1 to Dh via the switching transistor can be mainly generated by the backlight unit 111, and from the data line Dh + 1. Light transmitted through a region to which a liquid crystal pixel connected to (i−h + 1) data lines up to Di belongs via a switching transistor can be mainly generated by the backlight unit 112, and the data lines Di to Dm The light transmitted through the region to which the liquid crystal pixels connected to the (m−i + 1) data lines up to the switching line through the switching transistor can be mainly generated by the backlight unit 113.

  Note that the term “mainly” is used, for example, light transmitted through a region to which a liquid crystal pixel connected to (m−i + 1) data lines from data lines Di to Dm via switching transistors belongs. This is because not only the light generated by the backlight unit 112 but also a part of the light generated by other backlight units may be included.

  In FIG. 1, since the liquid crystal panel 109 is divided into three regions, three backlight portions 111, 112, and 113 are shown. However, the present invention is not limited to this, and an arbitrary number of backlight units may be used. In the above description, the liquid crystal panel 109 has been described as being divided in the direction in which the data lines are arranged. However, the present invention is not limited to this, and may be divided in the direction in which the gate lines are arranged. For example, the liquid crystal panel 109 is divided into a region represented by a liquid crystal pixel connected to the gate lines G1 to Gj via a switching transistor and a region represented by a liquid crystal pixel connected to the gate lines Gj + 1 to Gn via a switching transistor. May be. And a backlight part respond | corresponds to each divided | segmented area | region. Further, the liquid crystal panel 109 may be divided into a direction in which data lines are arranged and a direction in which gate lines are arranged. For example, the liquid crystal panel 109 may be divided into k pieces in the data line direction and l pieces in the gate line direction, and a total of k × l regions, and each of the k × l backlight units corresponds. May be.

  Data lines D1-Dm are connected to the data drivers 105, 106, and 107, which are a plurality of data drivers, and the potential of the connected data lines is controlled. As will be described later, each of the data driver 105, which is a plurality of data drivers, the data driver 106, and the data driver 107 is provided with a switching transistor for each data line from any of a plurality of timing controllers. Control data for controlling the light transmittance of the liquid crystal pixels connected via the control line is supplied, and the potential of the gate line is controlled according to the control data.

  In FIG. 1, three data driving units are shown. However, the present invention is not limited to this, and any number of data driving units may be used. Further, the number of backlight units and the number of data driving units do not need to match.

  The gate driver 108 sequentially selects the gate lines G1-Gn and supplies a potential for turning on the switching transistor connected to the selected gate line. As a result, the voltage applied to the data line is applied to the liquid crystal pixels connected to the switching transistors connected to the gate line selected by the gate driver 108, and the light transmitted through the liquid crystal pixels is transmitted. The amount of video is controlled and an image is displayed.

  A synchronization signal for sequentially selecting gate lines is input to the gate driver 108. In FIG. 1, this synchronization signal is input from the master timing controller 102, but the present invention is not limited to this. For example, the synchronization signal may be input from another slave timing controller, or the synchronization signal may be input from the distributor 101. Further, the display device may include a unit for generating the synchronization signal.

  The distributor 101 acquires video data. The video data is generated by reception by a television broadcast tuner, playback by a playback device of content recorded on a medium, operation of an application program or player program by a computer such as a personal computer, and is acquired by the distributor 101.

  The video data can be configured in units of frames of video to be displayed, and includes data representing the brightness of each pixel when displaying the video of the frame. The video data may also include data other than data representing pixel brightness, such as a synchronization signal, between the preceding and following frames.

  The distributor 101 distributes the acquired video data to the master timing controller 102, the slave timing controller 103, and the slave timing controller 104, which are a plurality of timing controllers, and outputs them. In one embodiment of the present invention, since a plurality of data driving units are used, the liquid crystal panel 109 is divided into blocks each composed of liquid crystal pixels controlled by each of the plurality of data driving units, and a plurality of timing controllers are connected. Each generates control data for controlling the liquid crystal pixels belonging to any of the plurality of blocks. Accordingly, the distributor 101 may be configured to divide and distribute the video data corresponding to the block including the liquid crystal pixels controlled by each of the plurality of timing controllers, and output the divided video data to each timing controller.

  Each of the master timing controller 102, the slave timing controller 103, and the slave timing controller 104, which are a plurality of timing controllers, acquires video data from the distributor 101. Then, control data for controlling the liquid crystal pixels is generated and output to the corresponding data driver.

  In one embodiment of the present invention, each of the plurality of timing controllers is caused to generate control data for controlling the liquid crystal pixels in the block of the liquid crystal panel 109, so that the amount of data to be processed per unit time by one timing controller is determined. Even if the liquid crystal panel is enlarged, an increase in processing speed of the timing controller can be suppressed.

  In one embodiment of the present invention, each of the plurality of timing controllers extracts the luminance distribution information of the pixels belonging to the corresponding block from the video data received from the distributor 101, and extracts the extracted luminance distribution information. Based on this, pixel control data is generated. Here, the corresponding block refers to a block to which a liquid crystal pixel controlled by a data driver that outputs control data for controlling the liquid crystal pixel by the timing controller belongs.

  In particular, in one embodiment of the present invention, the master timing controller 102 can receive the luminance distribution information extracted by the slave timing controllers 103 and 104. Then, the master timing controller 102 calculates the amount of light (also referred to as “light emission level”) generated by each backlight unit 111, 112, 113, and assigns the calculated amount of light to each backlight unit. Transmit to the slave timing controller connected to the data driver that controls the liquid crystal pixels in the area where each slave timing controller compensates the light transmittance of the liquid crystal pixels according to the amount of light received can do. Compensation of the light transmittance of the liquid crystal pixels is called pixel compensation processing.

  A communication path 114 for communication between the master timing controller 102 and the slave timing controller 103 is provided in the display device, and a communication path 115 for communication between the master timing controller 102 and the slave timing controller 104 is provided in the display device. It is done. For example, the I2C protocol can be used as the communication via this communication path. In the I2C protocol, only two signal lines are required for the communication path, and an increase in chip size can be prevented. Further, since the I2C protocol is a general communication standard, the reliability is high and the implementation cost can be reduced.

  FIG. 2 is a functional block diagram of a master timing controller according to an embodiment of the present invention. The master timing controller 201 includes a luminance distribution extraction unit 202, a light emission level information calculation unit 205, a pixel compensation unit 210, a master transmission / reception unit 207, a master transmission / reception control unit 206, and a backlight control signal transmission unit 211. . Moreover, you may provide the gate control signal transmission part 212 as needed.

  The luminance distribution extraction unit 202 extracts the luminance distribution information of the pixels of the block allocated to the master timing controller 102 among the pixels of the video data frame distributed by the distributor 101. For example, as illustrated in FIG. 2, the luminance distribution extraction unit 202 includes a maximum luminance extraction unit 203 and an average luminance extraction unit 204, and the maximum luminance extraction unit 203 uses the allocated block among the pixels of the frame. The maximum luminance value of the pixel is extracted, and the average luminance extraction unit 204 extracts the average luminance value of the pixels of the allocated block among the pixels of the frame. If necessary, the luminance distribution extraction unit 202 may also extract luminance dispersion, the median value of the luminance distribution, and the like.

  The “block assigned to the master timing controller 102” refers to a portion of an image represented by liquid crystal pixels controlled by the data driving unit 105 connected to the master timing controller 102. The blocks to which the slave timing controllers 103 and 104 are assigned can be defined in the same manner.

  The light emission level information calculation unit 205 uses the luminance distribution information extracted by the luminance distribution extraction unit 202 and the luminance distribution information received from the slave timing controllers 103 and 104 by the master transmission / reception unit 207 to use the master timing controller 102, The slave timing controllers 103 and 104 calculate the amount of light that should reach the liquid crystal pixels representing the pixels of the assigned block. And the light emission level of each backlight part is calculated. In calculating the light emission level, it may be considered that the light generated by the other backlight unit is added to the light generated by the backlight unit and the light reaches the liquid crystal pixels in the region to which the backlight unit is assigned.

  The light emission level of each backlight unit is calculated from the maximum luminance value extracted by the luminance distribution extraction unit 202 and the maximum luminance value received by the master transmission / reception unit 207. At this time, the amount of light corresponding to the maximum luminance of the pixels in the area to which each pack light unit is assigned is calculated as the light emission level, or the average luminance value extracted by the luminance distribution extraction unit 202 and the master transmission / reception unit 207. Is further referred to and the amount of light smaller than the maximum luminance of the pixels in the area corresponding to each backlight unit is calculated as the light emission level.

  In addition, if the difference in the amount of light calculated between adjacent backlight units is large, an image with unnatural brightness may be displayed. An adjustment unit 213 may be provided, and the spatial adjustment unit 213 may adjust the amount of light generated by each backlight unit. For example, a difference in light emission level between adjacent backlight portions is set within a predetermined range.

  In addition, if the temporal change in the amount of light generated by the backlight unit is large, the previous and next images may be displayed unnaturally, so the light emission level information calculation unit 205 includes a temporal adjustment unit 214. The temporal change in the amount of light may be adjusted by the temporal adjustment unit 214 so that the temporal change in the amount of light generated by each backlight unit becomes smooth. For example, the difference between the light emission level for displaying the current frame and the light emission level for displaying the next frame is set within a predetermined range.

  The backlight control signal transmission unit 211 transmits a control signal for causing the backlight unit to generate light at the light emission level calculated by the light emission level information calculation unit 205 to the backlight control unit 110.

  The pixel compensation unit 210 performs pixel compensation processing based on the light emission level of each backlight unit calculated by the light emission level information calculation unit 205 and transmits it to the data driving unit 105. Since the amount of light generated by each backlight unit varies temporally and spatially by the light emission level information calculation unit 205, the pixel compensation unit 210 compensates for the variation. For example, if the amount of light reaching the liquid crystal pixel becomes half of the maximum amount of light due to light emission of the backlight unit according to the light emission level, compensation is made so that the light transmittance of the liquid crystal pixel is doubled. Do.

  The master transmission / reception unit 207 communicates with each slave timing controller. The master transmission / reception unit 207 includes a luminance distribution information reception unit 208, transmits a request for luminance distribution information, and receives luminance distribution information returned in response to the request. The master transmission / reception unit 207 includes a light emission level information transmission unit 209, and transmits the amount of light calculated by the light emission level information calculation unit 205 to each slave timing controller.

  The master transmission / reception control unit 206 controls communication by the master transmission / reception unit 207. This control includes detection of whether an error has occurred in communication. Severity is given to errors in communication. The most serious error is a fatal error, and the minor error is a recoverable error. A fatal error is a severe error and corresponds to, for example, a case where information is transmitted to the slave timing controller but a reply to the transmission is not received within a predetermined time. A recoverable error is an error that occurs temporarily, and corresponds to, for example, a case where a reply has been received but noise or the like has occurred in the communication path and an error has occurred in the checksum.

  In one embodiment of the present invention, the contents of the process are varied according to the severity of errors in communication. When the most serious error occurs, the light emission level information calculation unit 205 adjusts temporally the amount of light generated by the backlight unit corresponding to the block assigned to the slave timing controller in which the error has occurred. And gradually change to the maximum amount. By setting the maximum amount, a more natural image can be displayed without performing pixel compensation processing by the slave timing controller. In addition, by adjusting temporally and gradually changing the amount of light to make a smooth change temporally, it is possible to prevent the brightness of the image from changing unnaturally.

  The gate control signal transmission unit 212 generates a timing signal corresponding to the timing at which the pixel compensation unit 210 transmits a signal to the data driving unit 105 and transmits the timing signal to the gate driving unit 108. The gate control signal transmission unit 212 may be configured to be generated by another unit, for example, the distributor 101, instead of being generated by the master timing controller 102.

  FIG. 3 is a functional block diagram of a slave timing controller according to an embodiment of the present invention. The slave timing controller 301 includes a luminance distribution extraction unit 302, a slave transmission / reception unit 305, a slave communication control unit 308, and a pixel compensation unit 309.

  The luminance distribution extraction unit 302 extracts the luminance distribution information of the pixels of the block to which the master timing controller 102 is assigned from the pixels of the video data frame distributed by the distributor 101. For example, as illustrated in FIG. 3, the luminance distribution extraction unit 302 includes a maximum luminance extraction unit 303 and an average luminance extraction unit 304, and the maximum luminance extraction unit 303 selects an assigned block among the pixels of the frame. The maximum luminance value of the pixel is extracted, and the average luminance extraction unit 304 extracts the average luminance value of the pixels of the allocated block among the pixels of the frame. If necessary, the luminance distribution extraction unit 302 may also extract luminance dispersion, the median value of the luminance distribution, and the like.

  The slave transmission / reception unit 305 communicates with the master timing controller 102. The slave transmission / reception unit 305 includes a luminance distribution information transmission unit 306, and transmits the luminance distribution information extracted by the luminance distribution extraction unit 302 in response to a request for luminance distribution information. The slave transmission / reception unit 305 includes a light emission level information reception unit 307, and receives information representing the amount of light generated by the backlight unit from the master timing controller 201.

  The slave communication control unit 308 controls the slave transmission / reception unit 305. This control includes detection of whether an error has occurred in communication. In addition, the slave communication control unit 308 outputs information representing the amount of light received by the light emission level information reception unit 307 to the pixel compensation unit 309.

  The pixel compensation unit 309 performs pixel compensation processing based on information representing the amount of light generated by the backlight unit received via the slave communication control unit 308, and data corresponding to the slave timing controller 301. Send to the drive.

  In one embodiment of the present invention, when the slave communication control unit 308 detects that the most serious error has occurred, the pixel compensation unit 309 determines that the backlight unit gradually generates the maximum amount of light. , Compensate the pixel. Further, when a minor error occurs, the pixel is compensated based on the information indicating the amount of light generated by the backlight unit that has been received through the slave communication control unit 308 before.

  The slave timing controller 301 may include a unit corresponding to the light emission level information calculation unit 205 and calculate the light emission level of the backlight unit based on the luminance distribution information extracted by the luminance distribution extraction unit 302. This is for the case where the light emission level information cannot be received from the master timing controller 201. In addition, the IC that realizes the slave timing controller 301 and the master timing controller 201 can be operated as the slave timing controller 301 or the master timing controller 201 by setting jumper lines or the like with the same configuration. .

  FIG. 4 is a timing chart showing the timing relationship between data acquisition by the distributor 101 and processing in each timing controller.

  When the distributor 101 acquires the image data 401, the distributor 101 distributes the image data 401 to the master timing controller and the slave timing controller. The master timing controller extracts the luminance distribution information 402 of the distributed image data, and the slave timing controller extracts the luminance distribution information 403 of the distributed image data. The slave timing controller transmits the extracted luminance distribution information 403 to the master timing controller, and the transmission data 404 flows through the communication path 115 or 114.

  The master timing controller calculates light emission level information 405 using the extracted luminance distribution information 402 and the luminance distribution information 403 extracted by the slave timing controller. The calculated light emission level information is transmitted to the slave timing controller, and transmission data 406 flows through the communication path 115 or 114.

  The master timing controller performs pixel compensation based on the calculated light emission level information 405 and outputs the result 408 to the data driver 105. The slave timing controller also receives the transmitted transmission data 406, performs pixel compensation based on the received transmission data 406, and outputs the result 409 to the data driver 106 or 107.

  When the result of pixel compensation is transmitted to the data driver, the distributor 101 acquires the next image data 407 and distributes the image data 407 to the master timing controller and the slave timing controller. The master timing controller extracts the luminance distribution information 410 of the distributed image data, and the slave timing controller extracts the luminance distribution information 411 of the distributed image data. The slave timing controller transmits the extracted luminance distribution information 411 to the master timing controller, and the transmission data 412 flows through the communication path 115 or 114.

  The master timing controller calculates the light emission level information 413 using the extracted luminance distribution information 410 and the luminance distribution information 411 extracted by the slave timing controller. The calculated light emission level information is transmitted to the slave timing controller, and transmission data 414 flows through the communication path 115 or 114.

  The master timing controller performs pixel compensation based on the calculated light emission level information 413 and outputs the result 416 to the data driver 105. The slave timing controller also receives the transmitted transmission data 414, performs pixel compensation based on the received transmission data 414, and transmits the result 417 to the data driver 106 or 107.

  When the result of pixel compensation is transmitted to the data driver, the distributor 101 acquires the next image data 415.

  Here, data 404, 406, 412, 414 transmitted / received between the master timing controller and the slave timing controller does not reach the transmission destination, or is different between when the data is transmitted and when it is received. May occur.

  For example, if the transmission data 404 does not reach the master timing controller, in one embodiment of the present invention, a request for luminance distribution information is transmitted from the master timing controller to the slave timing controller, and the luminance distribution information is received within a predetermined time. It is detected as a timeout error that is an error that is not received. When this timeout error is detected, the master timing controller sets the light emission level of the backlight unit assigned to the area of the liquid crystal pixel representing the pixel of the block assigned to the slave timing controller to the maximum level, Change.

  In addition, the difference in brightness distribution information between when it is transmitted and when it is received is that in one embodiment of the present invention, the slave timing controller detects errors such as checksums in the brightness distribution information. The data is added, and the master timing controller obtains a checksum of the transmission data 404 and compares it with the error detection data to detect a checksum error. When this checksum error is detected, the master timing controller discards the transmission data 404 and calculates the light emission level information 405 using the transmission data transmitted before the transmission data 404 by the slave timing controller. .

  Further, for example, the fact that the light emission level information does not reach the slave timing controller means that in one embodiment of the present invention, a light emission level information request is transmitted from the slave timing controller to the master timing controller, and the light emission level information is transmitted within a predetermined time. Detected as a timeout error where no information is received. When this timeout error is detected, the slave timing controller changes the light emission level of the backlight unit assigned to the liquid crystal pixel area representing the pixel of the block to which the slave timing controller is assigned to the maximum level. Assuming that pixel compensation processing is performed.

  Further, the difference between when the light emission level information is transmitted and when the light emission level information is received is that, in one embodiment of the present invention, the master timing controller detects error such as a checksum in the light emission level information. The data is added, and the slave timing controller obtains a checksum of the light emission level information and compares it with the error detection data to detect it as a checksum error. When this checksum error is detected, the slave timing controller discards the transmission data 406 and performs pixel compensation processing using the transmission data transmitted before the transmission data 406 by the master timing controller.

  FIG. 5 is a flowchart of processing after the master timing controller 102 acquires video data from the distributor 101 according to an embodiment of the present invention.

  In step S501, the luminance distribution extraction unit 202 extracts the luminance distribution information of the allocated block.

  As the processing in step S502, the master transmission / reception unit 207 and the master transmission / reception control unit 206 receive the luminance distribution information from each slave timing controller. As processing in step S503, the master transmission / reception control unit 206 determines whether an error has occurred in the reception processing in step S502.

  If an error does not occur and reception is successful, the process proceeds to step S504, and the light emission levels of all the backlight units are calculated.

  If a checksum error is detected, the process proceeds to step S505. For the slave timing controller in which the checksum error is detected, the luminance received from the slave timing controller before the checksum error is detected. The light emission level of the backlight unit is calculated using the distribution information.

  If a time-out error is detected, the process proceeds to step S506, and the slave timing controller in which the time-out error is detected is assigned to the liquid crystal pixel area representing the pixel of the block to which the slave timing controller is assigned. The light emission level of the backlight unit is set to the maximum level.

  After the processes of steps S504, S505, and S506, the process proceeds to step S507, and the temporal adjustment unit 214 adjusts the time of the light emission level. Spatial adjustment may be performed by the spatial adjustment unit 213 as necessary.

  In step S508, a backlight control signal is generated and output to the backlight control unit 110 by the backlight control signal transmission unit.

  In step S509, the master transmission / reception control unit 206 and the master transmission / reception unit 207 transmit the light emission level information of the backlight unit to each slave timing controller.

  In step S510, it is determined whether the transmission in step S509 has ended normally. For example, it is determined whether an acknowledge has been received from the slave timing controller. If not completed normally, the light emission level of the block in charge of the slave timing controller that has caused the transmission error is set to the maximum level.

  Following the processing in steps S509 and S510, the pixel compensation unit 210 performs pixel compensation and outputs the data to the data driving unit 105.

  FIG. 6 is a flowchart of processing after the slave timing controller according to the embodiment of the present invention receives video data from the distributor 101.

  As the processing in step S601, the luminance distribution extraction unit 302 extracts the luminance distribution information of the allocated block.

  As the processing in step S602, the slave transmission / reception unit 305 transmits the luminance distribution information to the master timing controller 102. As processing of step S603, the slave communication control unit 308 determines whether or not the transmission in step S502 has been completed normally. Whether or not the process has been completed normally is determined based on, for example, whether or not an acknowledgment has been received from the master timing controller 102.

  If no error has occurred and transmission has been successful, the process proceeds to step S604, and the light emission level of the backlight unit of the block in charge is calculated. This is in preparation for a case where the light emission level information cannot be received from the master timing controller 102.

  If an error is detected, the process proceeds to step S605, and the light emission level of the backlight unit of the allocated block is calculated as the maximum value. This is in preparation for the case where the light emission level information cannot be received from the master timing controller 102, as in step S604.

  After the processes in steps S604 and S605, the process proceeds to step S606, and the time adjustment of the light emission level calculated in steps S604 and S605 is performed. This is to prevent the brightness of the block handled by the slave timing controller from becoming abnormally large when the light emission level information cannot be received from the master timing controller 102. Note that the processes in steps S603, S604, S605, and S606 are not essential.

  In step S607, the slave communication control unit 308 and the slave transmission / reception unit 305 receive light emission level information from the master timing controller.

  In step S608, it is determined whether the reception in step S607 has been normally completed.

  If the signal is normally received in step S607, the process proceeds to step S609, and pixel compensation processing is performed by the pixel compensation unit 309.

  If a checksum error is detected in step S608, pixel compensation processing is performed using the light emission level information previously received from the master timing controller. Alternatively, pixel compensation processing may be performed using the light emission level information calculated in step S604 and temporally adjusted in step S606.

  If a time-out error is detected in step S608, pixel compensation processing is performed assuming that the light emission level is gradually set to the maximum. Alternatively, pixel compensation processing may be performed using the light emission level information calculated in step S605 and adjusted in time in step S606.

  FIG. 7 is a diagram illustrating an example in which the light emission level gradually becomes maximum. If the light emission level of the backlight unit is L1 at time T1 and the light emission level is gradually maximized at the time following time T1, the light emission level should not be suddenly increased to the maximum level LMAX. It shows a state in which the light emission level is raised smoothly and gently by time T2 thereafter.

DESCRIPTION OF SYMBOLS 101 Distributor, 102 Master timing controller, 103 Slave timing controller, 104 Slave timing controller, 105 Data drive part, 106 Data drive part, 107 Data drive part, 108 Gate drive part, 109 Liquid crystal panel, 110 Backlight control part, 111 Backlight unit, 112 Backlight unit, 113 Backlight unit, 114 communication path, 115 communication path

Claims (8)

A liquid crystal panel having a plurality of liquid crystal pixels, a plurality of data driving units, a plurality of timing controllers, and a plurality of backlight units ,
The plurality of liquid crystal pixels belong to any of a plurality of blocks,
Each of the plurality of data driving units corresponds to any of the plurality of blocks, and controls the light transmittance of the liquid crystal pixels belonging to the block,
Each of the plurality of timing controllers corresponds to one of the plurality of data driving units, and the corresponding data driving unit acquires data of a partial image displayed in a corresponding block, and the corresponding data driving unit Control data for controlling the light transmittance of the liquid crystal pixels belonging to the corresponding block to the corresponding data driver ,
Each of the plurality of backlight units emits light to transmit a liquid crystal pixel controlled by any of the plurality of data driving units,
Each of the plurality of timing controllers includes a luminance distribution extraction unit that extracts luminance distribution information of the partial image, and a pixel compensation unit that compensates the light transmittance of the liquid crystal pixels according to the light emission level of the backlight unit. The plurality of timing controllers comprises a master timing controller and a slave timing controller;
The master timing controller calculates a light emission level of each of the plurality of backlight units based on the luminance distribution information extracted by the luminance distribution information extraction unit of the plurality of timing controllers ;
The master timing controller is
If a request for luminance distribution information is transmitted to the slave timing controller and the luminance distribution information is not returned within a predetermined time, the slave timing controller transmits the liquid crystal pixels controlled by the corresponding data driver. Viewing device you and sets the level of emission of the backlight unit to the maximum level. The master timing controller is
If there is a checksum error in the luminance distribution information returned and acquired in response to the transmission of the luminance distribution information request to the slave timing controller, the plurality of the plurality of the luminance distribution information based on the luminance distribution information previously acquired from the slave timing controller. The display device according to claim 1 , wherein a light emission level of each of the backlight sections is calculated. The master timing controller, a display device according to claim 1 or 2, characterized in that for the plurality of backlight unit level of the respective light emission time and smoothly changed. A liquid crystal panel having a plurality of liquid crystal pixels belonging to any of a plurality of blocks, a plurality of data driving units, a plurality of timing controllers, and a plurality of backlight units ,
Each of the plurality of data driving units corresponds to one of the plurality of blocks, each of the plurality of timing controllers corresponds to one of the plurality of data driving units , and the corresponding data driving unit A luminance distribution extraction unit that extracts luminance distribution information of a partial image displayed in a corresponding block, and a pixel compensation unit that compensates the light transmittance of the liquid crystal pixel according to the light emission level of the backlight unit. The plurality of timing controllers include a master timing controller and a slave timing controller,
Each of the plurality of backlight units emits light for transmitting a liquid crystal pixel controlled by any of the plurality of data driving units.
A display device control method comprising:
Each of the plurality of data drivers controls the light transmittance of the liquid crystal pixels belonging to the corresponding block,
Each of the plurality of timing controllers acquires partial image data displayed in the corresponding block by the corresponding data driving unit, and the light transmittance of the liquid crystal pixels belonging to the corresponding block by the corresponding data driving unit Output control data to control the corresponding data driver ,
The master timing controller calculates a light emission level of each of the plurality of backlight units based on the luminance distribution information extracted by the luminance distribution information extraction unit of the plurality of timing controllers ;
If the master timing controller sends a request for luminance distribution information to the slave timing controller, and there is no response of the luminance distribution information within a predetermined time, the liquid crystal pixels controlled by the data driver corresponding to the slave timing controller the includes setting the level of the light emission of the backlight unit to the highest level, the control method for Viewing apparatus for transmitting. If there is a checksum error in the luminance distribution information acquired and returned in response to the transmission of the luminance distribution information request to the slave timing controller, the luminance distribution information previously acquired from the slave timing controller. The control method of the display device according to claim 4 , further comprising: calculating a light emission level of each of the plurality of backlight units based on the above. The master timing controller, comprising causing a plurality of backlight unit level of the respective light emitting temporally smoothly varying, according to claim 4 or 5, the control method of the display device. A liquid crystal panel having a plurality of liquid crystal pixels, a plurality of data driving units, a plurality of timing controllers, and a plurality of backlight units ,
The plurality of liquid crystal pixels belong to any of a plurality of blocks,
Each of the plurality of data driving units corresponds to any of the plurality of blocks, and controls the light transmittance of the liquid crystal pixels belonging to the block,
Each of the plurality of timing controllers corresponds to one of the plurality of data driving units, and the corresponding data driving unit acquires data of a partial image displayed in a corresponding block, and the corresponding data driving unit Control data for controlling the light transmittance of the liquid crystal pixels belonging to the corresponding block to the corresponding data driver ,
Each of the plurality of backlight units emits light to transmit a liquid crystal pixel controlled by any of the plurality of data driving units,
Each of the plurality of timing controllers includes a luminance distribution extraction unit that extracts luminance distribution information of the partial image, and a pixel compensation unit that compensates the light transmittance of the liquid crystal pixels according to the light emission level of the backlight unit. The plurality of timing controllers comprises a master timing controller and a slave timing controller;
The master timing controller calculates a light emission level of each of the plurality of backlight units based on the luminance distribution information extracted by the luminance distribution information extraction unit of the plurality of timing controllers , and an adjacent backlight unit The display device is characterized in that the difference in light emission level is within a predetermined range . A liquid crystal panel having a plurality of liquid crystal pixels belonging to any of a plurality of blocks, a plurality of data driving units, a plurality of timing controllers, and a plurality of backlight units ,
Each of the plurality of data driving units corresponds to one of the plurality of blocks, each of the plurality of timing controllers corresponds to one of the plurality of data driving units , and the corresponding data driving unit A luminance distribution extraction unit that extracts luminance distribution information of a partial image displayed in a corresponding block, and a pixel compensation unit that compensates the light transmittance of the liquid crystal pixel according to the light emission level of the backlight unit. The plurality of timing controllers include a master timing controller and a slave timing controller,
Each of the plurality of backlight units emits light for transmitting a liquid crystal pixel controlled by any of the plurality of data driving units.
A display device control method comprising:
Each of the plurality of data drivers controls the light transmittance of the liquid crystal pixels belonging to the corresponding block,
Each of the plurality of timing controllers acquires partial image data displayed in the corresponding block by the corresponding data driving unit, and the light transmittance of the liquid crystal pixels belonging to the corresponding block by the corresponding data driving unit Output control data to control the corresponding data driver ,
The master timing controller calculates a light emission level of each of the plurality of backlight units based on the luminance distribution information extracted by the luminance distribution information extraction unit of the plurality of timing controllers , and an adjacent backlight unit comprising the difference in emission levels within a predetermined range, the control method for Viewing device.

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