Interactivity sensor for electrophotographic printing

摘要

An apparatus in which the developability and interactivity of electrostatically charged particles in a mixture of particulate material is measured. The sensor apparatus includes a transparent member positioned closely adjacent to a developer roller of an electrophotographic printing machine. Electrostatically charged particles are attracted from the particulate mixture being transported by the developer roller to the member. A beam of energy is transmitted through the member. The intensity of the intemally reflected beam is detected and a signal generated indicative of the quantity of charged particles adhering to the member. A cleaning field bias is applied, to determine if a signal indicative of the charge particles being removed (interactivity) from the member is generated.