An image display apparatus comprising: (a) a display section of a plurality of LEDs arranged in an m-line by n-column matrix; (b) a vertical driver section being operable to select each consecutive line of said display section and a source current to each line; (c) a horizontal driver section being operable to supply driving current to each column of the display section corresponding to image data for the selected line; (d) a correction data memory section being operable to store correction data to correct externally input image data for an LED characteristic variation of each LED; (e) an image data correction section being operable to correct externally input image data (IMDATA) according to correction data (CRDATA) stored in said correction data memory section; and (f) a control section which controls each of the features of the display section, vertical driver section, horizontal driver section, and image data correction section; said image data correction section comprising: a buffer memory being operable to read out one line of correction data from said correction data memory section via said control section each time one line of corrected image data is output to said horizontal driver section; and a correction circuit being operable to receive image data from said control section and correction data from said buffer memory to output corrected imaga data to said horizontal driver section; characterized in that said buffer memory is made up of an interconnection of a first register and a second register, both of which are capable of storing one line of correction data, wherein said buffer memory is operable to read a next line of correction data into said second register from said correction data memory while said first register outputs one line of correction data to said correction circuit, and wherein said buffer memory is further operable to transfer one next line of correction data of said second register to said first register when said second register finishes reading said one next line of correction data. (a) a display section of a plurality of LEDs arranged in an m-line by n-column matrix; (b) a vertical driver section being operable to select each consecutive line of said display section and a source current to each line; (c) a horizontal driver section being operable to supply driving current to each column of the display section corresponding to image data for the selected line; (d) a correction data memory section being operable to store correction data to correct externally input image data for an LED characteristic variation of each LED; (e) an image data correction section being operable to correct externally input image data (IMDATA) according to correction data (CRDATA) stored in said correction data memory section; and (f) a control section which controls each of the features of the display section, vertical driver section, horizontal driver section, and image data correction section; a buffer memory being operable to read out one line of correction data from said correction data memory section via said control section each time one line of corrected image data is output to said horizontal driver section; and a correction circuit being operable to receive image data from said control section and correction data from said buffer memory to output corrected imaga data to said horizontal driver section;