Gain in electrophotography—II: Charge transfer configuration

The potential of the charge transfer imaging process for producing gain is considered under dynamic exposure conditions. A photoconductor with an ohmic or injecting contact to ground is assumed to be in virtual contact with a dielectric layer. The dielectric collects the charge transferred from the photoconductor under the influence of simultaneous exposure and application of high voltage. From simple arguments it can be demonstrated that the duration of the high voltage pulse is critical in optimizing the gain in the charge contrast. The qualitative results of the simple arguments are supported by detailed numerical calculations which demonstrate that a maximum gain of can be developed at a time approximately equal to times the carrier transit time of the photoconductor. The results of the calculations are supported by experiments.