| 摘要 |
PROBLEM TO BE SOLVED: To obtain the image distortion correction system for a CRT which is widely applied to horizontal distortion of a screen while keeping horizontal linearity by variably controlling a read start time and a speed of display data from a frame memory in the unit of horizontal periods with respect to a vertical direction. SOLUTION: Read speed correction data from a frame memory 6 to correct a difference between picture element intervals caused by linearity distortion in the horizontal direction are stored in advance in a horizontal linearity correction memory 20 and an analog signal 23 is generated. A reference clock correction circuit 14 decides a read speed correction amount from the frame memory 6 in the unit of horizontal period to generate a read reference clock control voltage 19. The analog signal 23 and the read reference clock control voltage 19 are given to a multiplier 24-a gate circuit 30, from which a read clock 32 is generated and display data of the frame memory 6 are read and displayed on a CRT 42. Thus, the correction system is realized, which is widely applicable to horizontal distortion of the screen. |
