Microscopic electrical defects in the photoreceptor termed Charge Deficient Spots (CDSs) can give rise to objectionable print defects in xerographic systems such as laser printers. Theoretical calculations of Space Charge Limited Currents (SCLC) between concentric cylindrical and spherical
electrodes show that a finite SCLC can be sustained, for a finite applied voltage, even as the radius of the emitting electrode goes to zero. Numerical simulations of the SCLC in a model system consisting of a ground plane with a finite circular emitting region and a parallel collector kept
at constant applied potential have shown that the SCLC varies
P. Ramesh, S. Jeyadev, Z. D. Popovic, "Space Charge Limited Currents from a Strip Shaped Emitter in a Parallel Plate Geometry" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP16), 2000, pp 489 - 492, https://doi.org/10.2352/ISSN.2169-4451.2000.16.1.art00020_2