Abstract
This thesis describes our new printing method of tone images by using "zigzag scanning" of electrostatically extracted ink jet which uses dielectric ink. The flight of the ink jet becomes a liquid thread from the nozzle, and ink turns into corpuscles at the other end of the liquid thread. At the printing process, we utilize in both liquid thread and corpuscles according to the gray levels of images. An ink flow was scanned right and left at the end of the nozzle (called zigzag scanning) according to the gray levels of images. The purpose of our research is the printing with having a high-quality in smoothed tone images but black and white. As for the zigzag scanning, resolution becomes 2 times bigger in an appearance without changing time and size of images recorded for to original picture image. In addition, the effect of decreasing a grainy touch on the image can be improved smoothly to a certain extent by utilizing such a tiny corpuscle in printing of high light area. In general, the scanning lines can be seen at the direction of sub-scanning according to the step width of the nozzle movement. Moreover, deterioration in the image quality might be occurred by the so called "moire pattern" of the image as an unwanted side effect, which is created under the mutual interruption between textures especially with the periodicity of the halftone dot image. The zigzag scanning contributes the smoothness of scanning lines, and maintains the periodicity of the halftone dot image as well, which reduces the degraded quality of moire and then enables an image quality rather natural through our human eyes.
