| 摘要 |
PURPOSE:To obtain printed matter of stable quality by obtaining an approximation formula for the representation of a relationship between a printing rate and a dot gain value, and calculating a printing rate for the obtaining of a desired dot gain value based on the approximation formula to perform a printing. CONSTITUTION:A pedestal is allowed to run at a speed V by rotating a motor 22 with a drive unit 66 to measure a dot gain value Da on a printed matter using a densitometer 72. Following this procedure, the motor 22 is caused to rotate at high speed to run the pedestal at a speed Vb for the measurement of a dot gain value Db. Next an approximation formula for the representation of a relationship between printing rates Va, Vb and dot gain values Da, Db is formulated by an arithmetic part 58 based on function data written into ROM 44, When a desired dot gain value Dn is entered by a keyboard 70, and a printing rate Vn is calculated by the arithmetic unit 58 on the basis of the earlier obtained approximation formula, outputting the printing rate to the drive unit 66 for printing. |
