| 摘要 |
PURPOSE:To provide proper amounts of charge for ink droplets by a method wherein the charging voltages according to the amounts of charge of the ink droplets jetted precedingly and followingly to the ink droplets to be charged are prememorized, and the ink droplets are charged by using the signal read at the time of charging operation. CONSTITUTION:A plurality of proper charging voltages precalculated from the combinations of the presence and absence of charges on the preceding and following ink droplets are memorized in a read-only memory (ROM) 33 for every row of dots in the deflecting direction. Then the printing information is memorized in a buffer memory 6 through an interface 5. On the other hand, while a shift register 31 storing the presence and absence of charges on the droplets is being shifted by a timing signal generator 7, the information of whether the preceding and following droplets are charged droplets or not is fed to the ROM33. Simultaneously, the desired digital signal is read from the ROM33 while accessing the addresses in the ROM33 through a bare-Ncounter 32. The digital signal read from the ROM33 is converted into an analong quantity by a digital-to-analog converter 34 and impressed on the charging electrode 4 through an amplifier 12. |
