Reproduction of halftone

Abstract

Abstract PURPOSE:To obtain more gradations by selecting a method of enabling a greater number of cells for forming dots when there are two or more kinds of methods of controlling the number of cells for reproducing virtually the same concentration. CONSTITUTION:A head unit 51 has ink jet nozzles 52 in two kinds of density, dark and light, each for black, yellow, magenta and cyan to compose one 3X3 matrix pixel to make the reflectively optical density equal between when four light does are formed for each pixel and when one dense dot is formed for each pixel. Here, for example, the gradation 4 can be expressed by four light dots or one dense dot. But in this manner, when there are more than one methods of controlling the number of cells for reducing virtually the same density, the one of enabling more cells for forming dots, namely, four light dots is selected to drive a printing head. This enables the reproduction of more gradations without increasing the number of cells while eliminating rough looking thereby producing an image of a high quality.

Inventors

• 👤 Nobuaki Sakurada
• 👤 櫻田　信晶
• 👤 Hideaki Kawamura
• 👤 秀明 河村
• 👤 Taku Sasaki
• 👤 卓 佐々木

Bibliographic Details