磁気印写における新しい中間調記録

抄録

This paper describes a new half-tone recording method in magnetography by utilizing the demagnetizing effect in short wave length recording. As the spatial frequency of recorded transition regions increases, the strength of magnetization decreases. Since the magnetic force, which attracts magnetic toners, depends on the strength of magnetization at the transition regions, the quantity of attracted magnetic toners depends on the spatial frequency of the transition regions.
A recording current of a low frequency was applied to a recording head for a video signal which represents a black image. The currents of higher frequencies were applied in accordance with changing of video signals from black to white. In order to realize a white image, either the current of the highest frequency, which exceeded a predetemined frequency, or the direct current was available.
A developed image was established by the facts that more toners were attracted in the areas between the transition regions with low spatial frequency and less toners with higher spatial frequency.
A produced copy has half-tone images whose reflective density ranges from the value over 1.4 to about 0.2.