Patent Publication Number: US-9886909-B2

Title: Display device and method for driving display device

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     Korean Patent Application No. 10-2015-0018328, filed on Feb. 6, 2015, in the Korean Intellectual Property Office, and entitled: “Display Device and Method For Driving Display Device,” is incorporated by reference herein in its entirety. 
     BACKGROUND 
     1. Field 
     Example embodiments of the inventive concept relate to electronic system. More particularly, example embodiments of the inventive concept relate to display devices including a plurality of driver integrated circuits (driver ICs). 
     2. Description of the Related Art 
     A display device may include a plurality of driver ICs for providing data signals to a display panel. Each of the driver ICs controls an image display of a corresponding display area among a plurality of display areas in the display panel. 
     In the display device (e.g., an organic light emitting diode (OLED) display), a control method of automatically controlling current (Automatic Current Limit; ACL) to lower luminance on the display when the entire screen is lighted at high luminance by image data signals in one frame, is used to reduce power consumption. Each of the driver ICs performs the ACL operation for the corresponding display area. 
     SUMMARY 
     According to example embodiments, a display device may include a display panel including a first display area and a second display area each including a plurality of pixels, a primary driver integrated circuit (IC) to receive first input image data corresponding to an image of the first display area, to determine a luminance correction factor based on a sum of a first On-Pixel-Ratio (OPR) of the first display area and a second OPR of the second display area and to output a first image data signal to which the first input image data is remapped using a luminance correction factor, a secondary driver IC to receive second input image data corresponding to an image of the second display area, to calculate the second OPR, and to output a second image data signal to which the second input image data is remapped using the luminance correction factor, and a scan driver configured to provide a scan signal to the display panel. 
     In example embodiments, the primary driver IC may include a first auto current limiter configured to calculate a total OPR of a previous frame including total luminance information of the first and second display areas, and to remap the first input image data of a present frame based on the total OPR of the previous frame such that a luminance of the first display area is adjusted. 
     In example embodiments, the secondary driver IC may include a second auto current limiter configured to remap the second input image data of the present frame based on the total OPR of the previous frame such that a luminance of the second display area is adjusted. 
     In example embodiments, the first auto current limiter may include an OPR calculator configured to calculate the first OPR based on the first input image data, a communicator configured to receive the second OPR from the second auto current limiter and to provide the total OPR and the luminance correction factor to the second auto current limiter, a total OPR calculator configured to calculate the total OPR based on the sum of the first OPR and the second OPR, a luminance determiner configured to determine the luminance correction factor that commonly determines the luminance of the first and second display areas based on the total OPR, and a data compensator configured to remap the first input image data to the first image data signal by applying the luminance correction factor. 
     In example embodiments, the second auto current limiter may include an OPR calculator configured to calculate the second OPR based on the second input image data, a communicator configured to provide the second OPR to the first auto current limiter and to receive the luminance correction factor from the first auto current limiter, and a data compensator configured to remap the second input image data to the second image data signal by applying the luminance correction factor. 
     In example embodiments, the primary driver IC may provide a data voltage corresponding to the first image data signal to the first display area, and the secondary driver IC provides a data voltage corresponding to the second image data signal to the second display area. 
     In example embodiments, the primary driver IC and the secondary driver IC may include a timing controller and a data driver. 
     In example embodiments, the first display area may include a first main display area that is a flat display area and a first sub-display area that is a bent display area adjacent to the first main display area. 
     In example embodiments, the primary driver IC may independently calculate an OPR of the first main display area and an OPR of the first sub-display area. 
     In example embodiments, the primary driver IC may calculate at least one of the OPR of the first main display area and the OPR of the first sub-display area, and remap at least a part of the first input image data corresponding to at least one of the first main display area and the first sub-display area. 
     In example embodiments, the second display area may include a second main display area that is a flat display area and a second sub-display area that is a bent display area adjacent to the second main display area. 
     In example embodiments, the secondary driver IC may independently calculate an OPR of the second main display area and an OPR of the second sub-display area. 
     In example embodiments, the primary driver IC and the secondary driver IC may be synchronized by a vertical synchronizing signal such that the first image data signal from the primary driver IC and the second image data signal from the secondary IC are substantially simultaneously output. 
     In example embodiments, the secondary driver IC may include first to (j)-th secondary data driver ICs, where j is an integer greater than 1. 
     In example embodiments, the primary driver IC and the secondary driver IC may be formed on the display panel by a Chip On Glass (COG) type or a Chip On Film (COF) type. 
     According to example embodiments, a method for driving a display device including a primary driver integrated circuit (IC) and a secondary driver IC that have embedded timing controllers may include calculating, by the primary driver IC, a first On-Pixel-Ratio (OPR) of pixels included in a first display area of a display panel based on first input image data, calculating, by the secondary IC, a second OPR of pixels included in a second display area of the display panel based on second input image data, providing the second OPR, by the secondary driver IC, to the primary driver IC, determining, by the main driver IC, a luminance correction factor which determines luminance of the display panel based on a sum of the first OPR and the second OPR, providing the luminance correction factor, by the main driver IC, to the secondary driver IC, remapping, by the main driver IC, the first input image data to a first image data signal by applying the luminance correction factor, and remapping, by the secondary driver IC, the second input image data to a second image data signal by applying the luminance correction factor. 
     In example embodiments, remapping the first input image data to the first image data signal may further include providing a data voltage corresponding to the first image data signal to the first display area. 
     In example embodiments, remapping the second input image data to the second image data signal may further include providing a data voltage corresponding to the second image data signal to the second display area. 
     In example embodiments, the first display area may include a first main display area that is a flat display area and a first sub-display area that is a bent display area adjacent to the first main display area. 
     In example embodiments, the primary driver IC may independently calculate an OPR of the first main display area and an OPR of the first sub-display area. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Features will become apparent to those of skill in the art by describing in detail exemplary embodiments with reference to the attached drawings in which: 
         FIG. 1  illustrates a block diagram of a display device according to example embodiments. 
         FIG. 2  illustrates a block diagram of an example of a primary driver IC and a secondary driver IC included in the display device of  FIG. 1 . 
         FIG. 3  illustrates a block diagram illustrating an example of first and second auto current limiters that are respectively included in the main and secondary driver ICs of  FIG. 2 . 
         FIG. 4  illustrates a timing diagram of an example of an operation of the main and secondary driver ICs of  FIG. 2 . 
         FIG. 5  illustrates a flow chart of an example of an operation of the primary driver IC which calculates total on-pixel ratio. 
         FIG. 6  illustrates a block diagram of an example of a secondary driver IC included in the display device of  FIG. 1 . 
         FIG. 7  illustrates a diagram of an example calculating on-pixel ratio according to a shape of a display panel included in the display device of  FIG. 1 . 
         FIG. 8  illustrates a diagram of another example calculating on-pixel ratio according to a shape of a display panel included in the display device of  FIG. 1 . 
         FIG. 9  illustrates a flow chart of a method for driving a display device according to example embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully hereinafter with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey exemplary implementations to those skilled in the art. Like reference numerals refer to like elements throughout. 
       FIG. 1  illustrates a block diagram of a display device according to example embodiments. 
     Referring to  FIG. 1 , the display device  1000  includes a display panel  100 , a primary driver integrated circuit (IC)  200 , a secondary driver IC  300 , and a scan driver  400 . In some embodiments, the display device  1000  may include a plurality of driver ICs each having a timing controller and a data driver. Each driver IC may control an output image which is represented on a corresponding area of the display panel  100 . 
     The display panel  100  may include a first display area D 1  and a second display area D 2 , each having a plurality of pixels P. The display panel  100  may be connected to the scan driver  400  via a plurality of scan lines SL 1  to SLn. The display panel  100  may be connected to the driver ICs  200  and  300  via a plurality of data lines DL 1  to DLm. The display panel  100  may include M (M is a positive integer) pixel columns each connected to the respective data lines DL 1  through DLm and N (N is a positive integer) pixel rows each connected to the respective scan lines SL 1  through SLn. Thus, the pixels P can be arranged in a matrix form and the display panel  100  can include N*M pixels. In some embodiments, an image displayed on the first display area D 1  may be controlled by the primary driver IC  200 , and an image display on the second display area D 2  may be controlled by the secondary driver IC  300 . Since these are examples, the display panel  100  may include K display areas (K is an integer greater than 2) so that the display device  1000  can include one primary driver IC and (K−1) secondary driver ICs. In some embodiments, the display panel  100  may include at least one bent (or curved) display area. 
     In some embodiments, the primary driver IC  200  and the secondary driver IC  300  may include a timing controller and a data driver. 
     The primary driver IC  200  may receive first input image data corresponding to an image of the first display area D 1 , generate a first image data signal to which the first input image data is remapped, and provide a data voltage corresponding to the first image data signal to the first display area D 1 . In some embodiments, the primary driver IC  200  may determine a luminance correction factor, that determines luminance of the whole image displayed on the entire display area, based on a sum of a first On-Pixel-Ratio (OPR) of the pixels P included in the first display area D 1  and a second OPR of the pixels P included in the second display area D 2 , and output the first image data signal to which the first input image data is remapped by using the luminance correction factor. The primary driver IC  200  may provide the luminance correction factor to the secondary driver IC  300 . Thus, the luminance correction factor may be determined by the primary driver IC  200  based on the OPR of all pixels and may be commonly applied to an image data signal remapping operation of the primary and secondary driver ICs  200  and  300 . 
     The OPR may be a ratio of the pixel number emitting predetermined grayscale light for the pixel number of the entire display panel  100 . In some embodiments, the OPR may be expressed as a percentage. The OPR may correspond to a ratio of a sum of grayscales of the input image data for a sum of full white grayscales. For example, if the OPR is about 100%, the display panel  100  displays a white image, and, if the OPR is about 0%, the display panel  100  displays a black image. When the pixels P include red pixels, green pixels, and blue pixels, the primary driver IC  200  (and the secondary driver IC  300 ) may respectively calculate the OPR of the red pixels (or red image data), the OPR of the green pixels (or green image data), and the OPR of the blue pixels (or blue image data). 
     In some embodiments, the primary driver IC  200  may include a first auto current limiter configured to calculate a total OPR of a previous frame including total luminance information of the first and second display areas D 1  and D 2 , and to remap the first input image data of a present frame based on the total OPR of the previous frame such that a luminance of the first display area is adjusted. The first auto current limiter will be described in detail with reference to  FIGS. 2 and 3 . 
     The secondary driver IC  300  may receive a second input image data corresponding to an image of the second display area D 2 , generate a second image data signal which is remapped data of the second input image data, and provide a data voltage corresponding to the second image data signal to the second display area D 2 . In some embodiments, the secondary driver IC  300  may calculate the second OPR, transmit the second OPR to the primary driver IC  200 , receive the luminance correction factor from the primary driver IC  200 , and output the second image data signal to which the second input image data is remapped using the luminance correction factor. The secondary driver IC  300  may not determine the luminance correction factor. 
     In some embodiments, the secondary driver IC  300  may include a second auto current limiter configured to remap the second input image data of the present frame based on the total OPR of the previous frame such that a luminance of the second display area is adjusted. The primary driver IC  200  and the secondary driver IC  300  may perform auto current limit (ACL) operation to adjust the luminance of the image displayed on the display panel  100 . 
     In some embodiments, the primary driver IC  200  and the secondary driver IC  300  may be formed on the display panel by a Chip On Glass (COG) type or a Chip On Film (COF) type. 
     The scan driver  400  may provide a scan signal to the display panel  100  via a plurality of scan lines SL 1  to SLn. In some embodiments, each of the scan lines SL 1  to SLn may be connected to pixels P arranged in one of the pixel rows. 
     As described above, the display device including the plurality of driver ICs may commonly use the luminance correction factor, which is determined by the primary driver IC  200 , for remapping the input image data so that the first and second display areas D 1  and D 2  may display images having substantially the same luminance. Thus, luminance uniformity (and output image uniformity) between the first and second display areas D 1  and D 2  can be improved. 
       FIG. 2  illustrates a block diagram of an example of a primary driver IC and a secondary driver IC included in the display device of  FIG. 1 . Referring to  FIGS. 1 and 2 , the primary driver IC  200  includes a first timing controller  220 , a first auto current limiter  240 , and a first data driver  260 , and the secondary driver  300  includes a second timing controller  320 , a second auto current limiter  340 , and a second data driver  360 . 
     The first timing controller  220  in the primary driver IC  200  may generate a plurality of control signals CONT 1  and provide the control signals CONT 1  to the first auto current limiter  240 , a scan driver  400 , and the first data driver  260 . The first timing controller  220  may control the scan driver  400  and the first data driver  260 . The first timing controller  220  may receive an input control signal and a first input image data DATA 1  from an image source such as an external graphic apparatus. The input control signal may include a main clock signal, a vertical synchronizing signal, a horizontal synchronizing signal, and a data enable signal. The first input image data DATA 1  may correspond to an image represented on the first display area D 1 . The first timing controller  220  may generate an image data signal, e.g., a digital image data signal, and corresponds to operating conditions of the display panel  100  based on the first input image data DATA 1 . The first timing controller  220  may provide the image data signal to the first auto current limiter  240 . In some embodiments, when the first auto current limiter  240  does not operate, the first timing controller  220  may provide the image data signal to the first data driver  260  directly. 
     The first auto current limiter  240  may calculate a total OPR of a previous frame including total luminance information of the first and second display areas D 1  and D 2 , remap the first input image data DATA 1  of a present frame to a first image data signal DATA 1 ′ based on the total OPR of the previous frame, such that a luminance of the first display area is adjusted. The first auto current limiter  240  may provide the first image data signal DATA 1 ′ to the first data driver  260 . The first auto current limiter  240  performs the auto current limit operation such that the luminance of the first display area D 1  can be adjusted. In some embodiments, the first auto current limiter  240  may remap the first input image data DATA 1  to decrease the luminance of the first display area D 1  when the luminance exceeds a predetermined reference luminance level. In some embodiments, the first auto current limiter  240  may be included in the first timing controller  220 . 
     The first data driver  260  may provide a data voltage DV corresponding to the first image data signal DATA 1 ′ to the first display area D 1 . For example, when the luminance of the first display area D 1  decreases, the data voltage DV decreases. Thus, the first auto current limiter  240  can decrease power consumption for driving the display panel  100 . 
     The second timing controller  320  included in the secondary driver IC  300  may generate a plurality of control signals CONT 2  and provide the control signals CONT 2  to the scan driver  400  and the second data driver  360  such that the scan driver  400  and the second data driver  360  may be controlled. The second timing controller  320  may receive the input control signal and a second input image data DATA 2  from the image source such as the external graphic apparatus. The input control signal may include a main clock signal, a vertical synchronizing signal, a horizontal synchronizing signal, and a data enable signal. The primary driver IC  200  and the secondary driver IC  300  may receive the same vertical synchronizing signal. In some embodiments, the primary driver IC  200  and the secondary driver IC  300  may be synchronized by the vertical synchronizing signal such that the first image data signal DATA 1 ′ and the second image data signal DATA 2 ′ are substantially simultaneously output. The second input image data DATA 2  may correspond to an image represented on the second display area D 2 . In some embodiments, the second timing controller  320  may generate an image data signal which has a digital type and corresponds to operating conditions of the display panel  100  based on the second input image data DATA 2 . The second timing controller  320  may provide the image data signal to the second auto current limiter  340 . In some embodiments, when the second auto current limiter  340  does not operate, the second timing controller  320  may provide the image data signal to the second data driver  360  directly. 
     The second auto current limiter  340  may remap the second input image data DATA 2  of the present frame (e.g., the image data signal) based on the total OPR of the previous frame such that luminance of the second display area D 2  is adjusted. The second auto current limiter  340  may provide the second image data signal DATA 2 ′ to the second data driver  360 . The second current limiter  340  performs the auto current limit technique such that the luminance of the second display area D 2  can be adjusted. In some embodiments, the second auto current limiter  340  may remap the second input image data DATA 2  to decrease the luminance of the second display area when the luminance exceeds a predetermined reference luminance level. For example, the second auto current limiter  340  may generate the second image data signal DATA 2 ′ to decrease the luminance of the displayed image so that power consumption for driving the display panel  100  can be decrease. In some embodiments, the second auto current limiter  340  may be included in the second timing controller  320 . 
     The second data driver  360  may provide a data voltage DV corresponding to the second image data signal DATA 2 ′ to the second display area D 2 . 
       FIG. 3  illustrates a block diagram of an example of first and second auto current limiters that are respectively included in the primary and secondary driver ICs of  FIG. 2 . Referring to  FIGS. 1 to 3 , the first auto current limiter  240  includes a first OPR calculator  242 , a communicator  244 , a total OPR calculator  246 , a luminance determiner  248 , and a data compensator  249 . The second auto current limiter  340  includes a second OPR calculator  344 , a communicator  344 , and a data compensator  349 . 
     The first OPR calculator  242  included in the first auto current limiter  240  may calculate the first OPR OPR 1  based on the first input image data DATA 1 . The first OPR OPR 1  may be OPR of the pixels of the first display area D 1  in one frame. In some embodiments, the first OPR OPR 1  may include OPR of red pixels, OPR of green pixels, and OPR of blue pixels. The first OPR calculator  242  may calculate the first OPR OPR 1  referring to grayscale data included in the first input image data DATA 1 . The first OPR calculator  242  may provide the first OPR OPR 1  to the total OPR calculator  246 . 
     The communicator  244  may receive the second OPR OPR 2  from the second auto current limiter  340  and provide the total OPR OPRY and the luminance correction factor LCF to the second auto current limiter  340 . The second OPR OPR 2  may be OPR of the pixels of the second display area D 2  in one frame. The communicator  244  may communicate with the communicator  344  included in the second auto current limiter  340 . The first auto current limiter  240  may calculate the total OPR OPRY by the communication, the first and second auto current limiters  240  and  340  may perform data remapping operation by commonly using the luminance correction factor LCF. In some embodiments, the communicators  244  and  344  may communicate using I2C communication method, SPI communication method, etc. 
     The total OPR calculator  246  may calculate the total OPR OPRY based on the sum of the first OPR OPR 1  and the second OPR OPR 2 . The total OPR OPRY may correspond to OPR of the whole pixels included in the display panel  100 . The total OPR calculator  246  may obtain luminance level of the entire image of the one frame according to the first and second input image data DATA 1  and DATA 2  (i.e., the luminance level of input image) using the total OPR OPRY. Here, when the luminance level of the input image data is greater than a predetermined reference luminance level, the first and second luminance determiners  248  and  348  may apply the same luminance correction factor LCF to the first and second input image data DATA 1  and DATA 2  so that luminance of output image that is displayed on the display panel  100  may decrease. The method of calculating the total OPR OPRY will be described in detail with reference to  FIG. 5 . 
     The luminance determiner  248  may determine the luminance correction factor LCF that commonly determines the luminance of the first and second display areas D 1  and D 2  based on the total OPR OPRY. For example, the luminance determiner  248  may determine the luminance correction factor LCF based on a ratio of the expressible luminance level of the display device  100  to the luminance level of the input image. In some embodiments, the luminance determiner  248  may include a lookup table having luminance correction factors LCF corresponding to each total OPR OPRY that includes luminance level information of the input image. The luminance determiner  248  may provide the luminance correction factor LCF to the communicator  244  and the data compensator  249 . Thus, the luminance correction factor LCF may be used in the auto current limit drive of the secondary driver IC  340 . Therefore, the whole image data signals may be corrected to substantially the same scale. The luminance correction factor LCF may be a scaling factor for decreasing the luminance level (or grayscale level) of the image data signal. 
     The data compensator  249  may remap the first input image data DATA 1  to the first image data signal DATA 1 ′ by applying the luminance correction factor LCF. For example, if the luminance range is 256 grayscales, the data compensator  249  may change (or compensate) the image data signal output from the first timing controller  242  to the first image data signal DATA 1 ′ using the following Equation 1.
 
 R′=R (1−LCF/256)
 
 G′=G (1−LCF/256)
 
 B′=B (1−LCF/256)  Equation 1
 
     where R, G, and B are red, green, and blue image data signals that are input to the data compensator  249 , R′, G′, and B′ are compensated red, green, and blue image data signals that are output from the data compensator  249 , and LCF is the luminance correction factor that is determined by the luminance determiner  248 . 
     The first auto current limiter  240  may further include dither (not illustrated) for dithering the first image data signal DATA 1 ′. 
     The primary driver IC  200  may display an image having corrected luminance based on the first image data signal DATA 1 ′. 
     The second OPR calculator  342  may calculate the second OPR OPR 2  based on the second input image data DATA 2 . The second OPR OPR 2  may be OPR of the pixels of the second display area D 2  in one frame. In some embodiments, the second OPR OPR 2  may include OPR of red pixels, OPR of green pixels, and OPR of blue pixels. The second OPR calculator  342  may calculate the second OPR OPR 2  referring to grayscale data included in the second input image data DATA 2 . The second OPR calculator  342  may provide the second OPR OPR 2  to the communicator  344 . 
     The communicator  344  may provide the second OPR OPR 2  to the first auto current limiter  240  and receive the luminance correction factor LCF from the first auto current limiter  240 . The communicator  344  may communicate with the communicator  244  included in the first auto current limiter  240 . The communicator may provide the luminance correction factor LCF to the data compensator  349 . 
     The data compensator  349  may remap the second input image data DATA 2  to the second image data signal DATA 2 ′ by applying the luminance correction factor LCF. Thus, the first and second input image data DATA 1  and DATA 2  may be corrected to substantially the same scale due to the luminance correction factor LCF that is commonly applied to the first and second input image data DATA 1  and DATA 2 . 
     The second auto current limiter  340  may further include a dither (not illustrated) for dithering the second image data signal DATA 2 ′. 
     As described above, the display device  100  according to example embodiments includes the first primary driver IC  200  configured to determine a common luminance correction factor LCF based on the communication between the primary driver IC  200  and the secondary driver IC  300 . Thus, image data signals for a frame may be remapped to have substantially the same luminance level. Therefore, luminance uniformity of the entire image of the frame can be improved. 
       FIG. 4  illustrates a timing diagram of an example of an operation of the primary and secondary driver ICs of  FIG. 2 . Referring to  FIGS. 2 to 4 , the primary driver IC  200  and the secondary driver IC  300  may output image data DATA that is compensated by the luminance correction factor LCF. 
     As illustrated in  FIG. 4 , in some embodiments, the primary driver IC  200  and the secondary driver IC  300  may substantially simultaneously receive a vertical synchronizing signal VSYNC and a horizontal synchronizing signal HSYNC. In some embodiments, the first and second auto current limiters  240  and  340  may be synchronized by the vertical synchronizing signal VSYNC such that the first image data signal DATA 1 ′ and the second image data signal DATA 2 ′ may be substantially simultaneously output. 
     The first and second image data signals DATA 1 ′ and DATA 2 ′ that are respectively output from the primary driver IC  200  and the secondary driver IC  300  during an (N−1)th frame are corrected data signals by the luminance correction factor LCF(N−2) that is calculated at an (N−2)th frame. In the (N−1)th frame, the primary driver IC  200  may calculate the first OPR OPR 1  and the secondary driver IC  300  may calculate the second OPR OPR 2 . Then, the secondary driver IC  300  may provide the second OPR OPR 2  to the primary driver IC  200 . The primary driver IC  200  received the second OPR OPR 2  may determine the luminance correction factor LCF(N−1) based on the sum of the first OPR OPR 1  and the second OPR OPR 2 . The primary driver IC  200  may provide the luminance correction factor LCF(N−1) to the secondary driver IC  300 . 
     In an (N)th frame, the primary driver IC  200  and the secondary driver IC  300  may be synchronized by the vertical synchronizing signal VSYNC. The primary driver IC  200  and the secondary driver IC  300  may respectively output the first and second image data signals DATA 1 ′ and DATA 2 ′ to which the luminance correction factor LCF(N−1) is applied. The display panel  100  may display an image based on the first and second image data signals DATA 1 ′ and DATA 2 ′. The primary driver IC  200  may generate the luminance correction factor LCF(N−1) of the (N)th frame and remap the image data signal by applying the luminance correction factor LCF(N−1) to the image data signal of an (N+1)th frame. 
     As described above, the primary driver IC  200  and the secondary driver IC  300  may communicate with each other and may output (or generate) the corrected image data signals to which the common luminance correction factor LCF is applied. 
       FIG. 5  illustrates a flow chart of an example of an operation of the primary driver IC which calculates total on-pixel ratio. Referring to  FIGS. 2, 3, and 5 , the primary driver IC  200  may calculate the total OPR Y and Y′ based on the first OPR OPR 1  and the second OPR OPR 2 . 
     The primary driver IC  200  may calculate the first OPR OPR 1  based on the first input image data DATA 1  (S 120 ). The first OPR OPR 1  may be OPR of the pixels included in the first display area D 1 . The primary driver IC may calculate a first red OPR OPRr 1 , a first green OPR OPRg 1 , and a first blue OPR OPRb 1 , when the pixels include red, green, and blue pixels. 
     The secondary driver IC  300  may calculate the second OPR OPR 2  based on the second input image data DATA 2  (S 220 ). The secondary driver IC  300  may calculate a second red OPR OPRr 2 , a second green OPR OPRg 2 , and a second blue OPR OPRb 2 , when the pixels include red, green, and blue pixels. 
     The primary driver IC  200  may calculate the sum (i.e., OPRr, OPRg, and OPRb) of the first OPR OPR 1  (e.g., OPRr 1 , OPRg 1 , and OPRb 1 ) and the second OPR OPR 2  (e.g., OPRr 2 , OPRg 2 , and OPRb 2 ) (S 140 ). 
     In some embodiments, the primary driver IC  200  may compare a blue OPR OPRb with red and green OPRs OPRr and OPRg (S 160 ). 
     If the blue OPR OPRb is smaller than or equal to the red and green OPRs OPRr and OPRg, a luminance equation Y is used to calculate the total OPR OPRY (S 170 ). If the blue OPR OPRb is larger than the red and green OPRs OPRr and OPRg, ae luminance equation Y′ is used to calculate the total OPR OPRY (S 180 ). The luminance equations are represented by the following Equation 2.
 
 Y =AKrOPRr+AKgOPRg+AkbOPRb
 
 Y ′=BKrOPRr+BKgOPRg+BkbOPRb  Equation 2
 
     where AKr, AKg, AKb, BKr, BKg, and BKb are coefficients depending on organic light emitting diode (OLED) material characteristics. 
     The equation Y is an equation developed for compensating for ordinary luminance, and the luminance Y′ is an equation developed for automatically limiting current depending on the material characteristics of OLED. The equation Y′ increases dependence on the image data signal applied to the blue pixels compared with the equation Y. Since the Equations 2 is an example, method for correcting the luminance are not limited thereto. 
     The primary driver IC  200  may determine the luminance correction factor LCF based on the total OPR PORY. In some embodiments, the primary driver IC  200  may determine the luminance correction factor LCF via a lookup table. 
       FIG. 6  illustrates a block diagram of an example of a secondary driver IC included in the display device of  FIG. 1 . Referring to  FIGS. 1 and 6 , the display device  100  may include a display panel  110 A having a plurality of display areas, e.g., j display areas, a primary driver IC  200 A, and a secondary driver IC  300 A. In some embodiments, the secondary driver IC  300 A may include first to (j)th secondary driver ICs. 
     In some embodiments, the display panel  100 A may include first to fourth display areas D 1 , D 2 , D 3 , and D 4 . The first display area D 1  may be connected to the primary driver IC  200 A. First to third secondary driver ICs  320 ,  340 , and  360  may be connected to the second to fourth display areas D 2 , D 3 , and D 4 , respectively. 
     The primary driver IC  200 A may calculate an OPR of the first display area D 1 . The first to third secondary driver ICs  320 ,  340 , and  360  may calculate OPRs of the second to fourth display areas D 2 , D 3 , and D 4 , respectively. The first to third secondary driver ICs  320 ,  340 , and  360  may provide the calculated OPRs to the primary driver IC  200 A. 
     The primary driver IC  200 A may determine the luminance correction factor for determining the luminance of the whole display areas based on the OPRs of the first to fourth display areas D 1 , D 2 , D 3 , and D 4 . The primary driver IC  200 A may provide the luminance correction factor to the first to third secondary driver ICs  320 ,  340 , and  360 . 
     The primary driver IC  200 A and the first to third driver ICs  320 ,  340 , and  360  may remap image data signals based on the luminance correction factor to decrease power consumption for driving the display panel  100 , and may display an image on the display panel  100 A based on the remapped image data signals. 
       FIG. 7  illustrates a diagram of an example calculating on-pixel ratio according to a shape of a display panel included in the display device of  FIG. 1 .  FIG. 8  illustrates a diagram of another example calculating on-pixel ratio according to a shape of a display panel included in the display device of  FIG. 1 . 
     Referring to  FIGS. 1, 7, and 8 , the display device may include a display panel  100 B and  100 C having a plurality of display areas. The display areas may have various shapes. 
     The primary driver IC  200 B and  200 C may control an image displayed on the first display area D 1 . The secondary driver IC  200 B and  200 C may control an image displayed on the second display area D 2 . 
     In some embodiments, as illustrated in  FIG. 7 , the first display area D 1  may include a first main display area D 11  that is a flat display area and a first sub-display area D 12  that is a bent display area adjacent to the first main display area D 11 . In some embodiments, the primary driver IC  200 B may independently calculate an OPR of the first main display area D 11  (hereinafter, represented to as ‘OPRM 1 ’) and an OPR of the first sub-display area D 12  (hereinafter, represented to as ‘OPRS 1 ’). In some embodiments, the primary driver IC  200 B may calculate at least one of the OPRM 1  and OPRS 1 , and may remap at least a part of the first input image data corresponding to at least one of the first main display area D 11  and the first sub-display area D 12 . For example, when the first sub-display area D 12  displays black image, the first sub-display area D 12  may have very low luminance. Thus, the primary driver IC  200 B does not need to perform the auto current limit operation at the first sub-display area D 12 . As a result, the primary driver IC  200 B may only calculate the OPRM 1 , and calculate the luminance correction factor based on the OPRM 1  and the second OPR that is received from the secondary driver IC  300 B. 
     In some embodiments, the primary driver IC  200 B may remap only the image data signals corresponding to the first main display area D 11  based on the luminance correction factor. In some embodiments, the primary driver IC  200 B may remap the image data signals corresponding to the first main display area D 11  and the first sub-display area D 12  based on the luminance correction factor. The secondary driver IC  300 B may receive the luminance correction factor from the primary driver IC  200 B and remap the image data signals corresponding to the second display area D 2  based on the luminance correction factor. 
     As illustrated in  FIG. 8 , the second display area D 2  may include a second main display area D 21  that is a flat display area and a second sub-display area D 22  that is a bent display area adjacent to the second main display area D 21 . In some embodiments, the secondary driver IC  300 C may independently calculates an OPR of the second main display area D 21  (hereinafter, represented to as ‘OPRM 2 ’) and an OPR of the second sub-display area D 22  (hereinafter, represented to as ‘OPRS 2 ’). 
     For example, the primary driver IC  200 C and the secondary driver IC  300 C may calculate the OPRs of selected display areas according to a command. In some embodiments, when the first and second main display areas D 11  and D 12  display a black image (or be turned off), only the OPRS 1  and OPRS 2  (i.e., the OPRs of the first and second sub-display areas D 12  and D 22 ) are calculated. Here, the primary driver IC  200 C and the secondary driver IC  300 C may perform remapping image data corresponding to the first and second sub-display areas D 12  and D 22 . 
     In some embodiments, the only OPRM 1  and OPRM 2  (i.e., the OPRs of the first and second main display areas D 11  and D 21 ) may be calculated. Here, the primary driver IC  200 C and the secondary driver IC  300 C may perform remapping image data corresponding to the first and second main display areas D 11  and D 21 . On the other hand, the primary driver IC  200 C and the secondary driver IC  300 C may perform remapping image data the whole display areas D 11 , D 12 , D 21 , and D 22 . 
     As described above, the display device may calculate OPR corresponding to only portions of the display area required to luminance correction or remap partial image data corresponding to the portions. Thus, power consumption for remapping the image data can be decreased. 
       FIG. 9  illustrates a flow chart of a method for driving a display device according to example embodiments. 
     Referring to  FIGS. 1 to 9 , the method for driving the display device may include calculating a first OPR (S 10 ), calculating a second OPR and providing the second OPR to a primary driver IC (S 20 ), and determining a luminance correction factor based on the first OPR and the second OPR (S 30 ). The primary driver IC may provide the luminance correction factor to a secondary driver IC (S 40 ). Then, the primary driver IC may remap first input image data to a first image data signal (S 50 ) by applying the luminance correction factor and provide a data voltage corresponding to the first image data signal to a first display area to display an image on the first display area (S 55 ). The secondary driver IC may remap second input image data to a second image data signal (S 60 ) by applying the luminance correction factor and provide a data voltage corresponding to the second image data signal to a second display area to display an image on the second display area (S 65 ). The display device may include the primary and secondary driver ICs each having a timing controller (and a data driver). 
     In some embodiments, the first display area may include a first main display area that is a flat display area and a first sub-display area that is a bent display area adjacent to the first main display area. In this, the primary driver IC may independently calculate an OPR of the first main display area and an OPR of the first sub-display area. Similarly, the second display area may include a second main display area that is a flat display area and a second sub-display area that is a bent display area adjacent to the second main display area. In this, the primary driver IC may independently calculate an OPR of the second main display area and an OPR of the second sub-display area. 
     Since methods for driving the display device are described above referred to  FIGS. 1 to 8 , duplicate descriptions will not be repeated. 
     The present embodiments may be applied to any display device and any system including the display device. For example, the present embodiments may be applied to a television, a computer monitor, a laptop, a digital camera, a cellular phone, a smart phone, a smart pad, a personal digital assistant (PDA), a portable multimedia player (PMP), a MP3 player, a navigation system, a game console, a video phone, etc. 
     By way of summation and review, as described above, the display device having a plurality of driver ICs for driving a plurality of display areas may determine the common luminance correction factor based on the communication between the primary driver IC and the secondary driver IC. Thus, image data signals for a frame may be remapped to have substantially the same luminance level. Thus, image data signals for a frame may be remapped to have substantially the same luminance level. Therefore, luminance uniformity of the entire image of the frame can be improved. Further, the display device may calculate OPR corresponding to only portions of the display area required to luminance correction or remap partial image data corresponding to the portions. Thus, power consumption for remapping the image data can be decreased. 
     In addition, the method for driving the display device including the plurality of driver ICs for driving a plurality of display areas may calculate total OPR of the entire display area based on the communication between the primary driver IC and the secondary driver IC, and perform the data remapping operation for decreasing the luminance of the output image based on the total OPR and the luminance correction factor that is generated in the primary driver IC and commonly applied to the primary driver IC and the secondary driver IC. Thus, output image uniformity may be improved. 
     In contrast, display areas that are separately controlled by respective corresponding driver ICs use different On-Pixel-Ratio (OPR) each corresponding to the respective display areas, so that the display areas may display images each having different luminance, decreasing output image uniformity. 
     Example embodiments have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent to one of ordinary skill in the art as of the filing of the present application, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims.