1993 Volume 32 Issue 3 Pages 253-258
The potential distribution in the development zone of an electrophotographic copying machine is analysed using finite element method (FEM).
In the calculation, a finite rectangular wave form pattern is assumed for the latent image on the photosensitive film. It is found that while the potential reaches a maximum at the center of the charged regions of the rectangular wave form pattern, a maximum also exists in the uncharged regions and that it shifts to the development space. At the same time, the electric field reaches a maximum outside the outermost charged pattern. In moving along the surface of the photosensitive film from the center of a charge region to that of the uncharged region, the field charges its direction by180°.
A new equation for evaluating contrast potential is deduced. The effect of bias voltage, ratio of dielectric constant of the film and that of the development space, film thickness, and contrast potential are descussed.
