NIHON GAZO GAKKAISHI (Journal of the Imaging Society of Japan)
Online ISSN : 1880-4675
Print ISSN : 1344-4425
ISSN-L : 1344-4425
Volume 42 , Issue 4
Showing 1-19 articles out of 19 articles from the selected issue
Original Papers
  • Shougo SATO, Manabu TAKEUCHI
    2003 Volume 42 Issue 4 Pages 326-332
    Published: 2003
    Released: July 01, 2006
    The image-density-decrease phenomenon, which occurs at the initial printing with a brand new developing cartridge and at a printing done after several days of rest, during which printing is not done, was studied in the mono-component developing process. The toner charge, q/m, and toner supply, m/a, were measured by a suction type Faraday cage. The mechanism of the image-density-decrease phenomenon is discussed based on q/m, m/a and fluidity of toner. The image-density-decrease phenomenon was found to occur with decrease in m/a, and not with increase in q/m. The cause of the decrease in m/a is the shortage of the toner supply to the supply roller. Finally, modifications of the developing unit and the toner additives to eliminate the image-density-decrease phenomenon are proposed.
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  • Shinji SASAHARA, Tetsuo ASANO
    2003 Volume 42 Issue 4 Pages 333-339
    Published: 2003
    Released: July 01, 2006
    In this paper, we propose an algorithm that adaptively arranges or grows clusters according to tone slope of the cluster-dot halftoning by bubble packing. This technique locates small cluster regions to increase effective resolution on the portion of rapid tone change, and locates large cluster regions to increase effective tone scale on the portion of mild tone change to achieve a good balance between effective resolution and effective tone scale. Since the clusters are arranged irregularly, our technique has an effect of suppressing interference with regular patterns, such as moiré, and produces a good tone reproduction without occurring artifacts.
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    2003 Volume 42 Issue 4 Pages 340-347
    Published: 2003
    Released: July 01, 2006
    In normal operation during roller rotation in the mono-component development system, a current flows through each system part (i.e. development roller, blade, and supply roller). The possible mechanism of generation of these currents is discussed, focusing on the surface potential at the development roller surface. The surface charge of the development roller, which is determined by both the toner charge and the charge trapped on the development roller surface are released by contacting with the supply roller. It was clear that this release of charge is observed as a current together with the current generated from toner charging and/or the toner transport. It was found that the surface characteristics of the development roller considerably affected the value of the toner charging and the charge retention of the surface as well as the magnitude and the direction of the current. From these results, a possible mechanism for this current generation is proposed.
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Review Papers
Imaging Today
“A Recent Trend of Tandem Color Laser Printing Technologies&rdquo