| 摘要 |
PURPOSE:To measure a dot area ratio in color printing by inferring tristimulus values of a part for which it is desired to derive the dot area ratio, by specific expressions, and deriving a value of the dot are ratio by non-linear optimization so that the errors from the tristimulus values of the same measured part are minimum. CONSTITUTION:A printed matter by three-color lap printing of yellow, magenta and cyan ink, or each solid density part of yellow, magenta and cyan ink of a proof, paper, and a part of magenta, yellow and cyan, for which it is desired to derive its dot area ratio are brought to a colorimetry. Subsequently, tristimulus values of the part for which it is desired to derive the dot area ratio is inferred by expressions. Next, the dot area ratio is derived by non-linear optimization so that an error of the measured value of the tristimulus values of the same part and the inferred tristimulus values becomes minimum, by which the dot area ratio in color printing is measured. |
