| 摘要 |
PURPOSE:To perform stable recording, by realizing the 2K<2> gradation by the higher rank K2-bit (better than K1) of gradation data in a density region inferior to a gradation property in an one-pixel unit by the control of a current supply pulse width and enlarging areal gradation on the basis of a lower rank (m2+n2)- bit. CONSTITUTION:256 pixels are continuously read from a line memory, in which data of 6-bit/64-gradation is written, on the basis of the 8-bit address from an address counter 6. In a density region superior to a gradation property, 2K<1> gradation due to the higher rank K1-bit of gradation data is realized in an one-pixel unit on the basis of the control of a current supply pulse width by current supply pulse generating means 8, 9, 13 and current supply control means 6, 10-12 and areal gradation is enlarged in a matrix of longitudinal and lateral 2<m1>X2<n1> pixels on the basis of lower rank (m1+n1)-bit. In a region inferior to a gradation properly, an one-pixel unit is realized on the basis of 2K<2> due to a higher rank K2-bit (<K1) and the number of gradations are enlarged on the basis of a lower rank (m2+n2) (>m1+n1) bit. By this method, an image of high gradation can be stably recorded. |
