| 摘要 |
PURPOSE:To prevent the generation of pseudo patterns by minimizing various density errors with a small number of gradations. CONSTITUTION:This error diffusion circuit includes adder circuits 31, 32 which add the reproduction errors generated in the past in input video signals of n-bit, a bit conversion circuit 33 which converts the diffusion output signals to signals of m(<=n-1) bit outputted therefrom, an error detecting circuit 50 which detects the difference between a set correction luminance level and the diffusion output signals, weights the error and outputs the error and delay circuits 36, 37 which delay the error load output signals outputted therefrom and output the delayed signals as a reproduction error to the adder circuits 31, 32. Smooth response is obtd. with the signals of the bit number smaller than the bit number of the original video input signals without degradation in light emission luminance. A changeover control circuit 54 outputs the different correction luminance levels 1, 2,...k of a correction luminance level setting circuit 52 by changing over these levels and, therefore, even if the input levels are the same continuous value, the levels of the error load output values do not attain the same continuous values and the generation of the pseudo patterns is prevented. |
