| 摘要 |
PURPOSE:To obtain a digital character signal having a high resolving power with an ordinary image pickup tube, by combining M-number of kinds of horizontal scanning mode, where phases are shifted in the vertical direction by the 1/M period, and N-number of kinds of sampling mode where phases are shifted in the horizontal direction by the 1/N period. CONSTITUTION:An image pickup tube 5 of an image pickup part 6 is capable of digitizing 400X400 picture elements. An image pickup output 21 is converted to a binary signal in a comparator 22 and is sampled in a sampling circuit 23 by a sampling pulse SP. A sampled digital character signal 24 is stored in memories (#1-#4) through an interface 25. A synchronizing signal generating circuit 27 has M-number of kinds of mode (M=2) to output horizontal synchronizing signals HSY where phases are shifted from one another by the 1/M period, and a sampling pulse generating circuit 28 has N-number of kinds of mode (N=2) to output sampling pulses where phases are shifted from one another by the 1/N period. Picture elements in MXN (4) modes are stored in memories #1-#4 of the memory 26 successively. Contents of this memory 26 are synthesized in a synthesizing processing circuit 29 to obtain a character signal, which consists of 800X 800 picture elements to have a high resolving power, in an output part 8. |
