Control system for an electrophotographic printing machine

摘要

An apparatus in which toner particle concentration within a developer mixture and charging of the photoconductive surface are controlled. A first test area and a second test area are recorded on the photoconductive surface. Toner particles are deposited on the first test area having a greater density than the toner particles deposited on the second test area. Concentration of toner particles within the developer mixture is controlled in response to the toner particle density of the first test area. Charging of the photoconductive surface is regulated in response to the toner particle density of the second test area.