Quality Control Test Equipment for Photoreceptors, Charge Rollers and Magnetic Rollers

A new computer-controlled test system for mapping photoreceptor properties such as charge acceptance and discharge voltage will be described. The system allows rapid scanning of a photoreceptor to: 1) characterize its functional quality and uniformity, and 2) detect both charging and discharge defects of 50-100 μm in diameter or larger. The system can also perform conventional electrophotographic measurements to obtain dark decay, photo-induced discharge curves (PIDC), and fatigue properties. In addition to testing the complete photoreceptor product, a unique feature of the system is its ability to perform measurements on the sub-layers in a photoreceptor. These measurements include examining the substrate for cleanliness, and measuring the thickness and uniformity of the polymer barrier layer and the charge generation layer (CGL) in a layered organic photoconductor (OPC). The design of the system will be described, and its performance will be demonstrated with application examples. Test equipment for the charge roller and the magnetic roller in toner cartridges using similar electrostatic charge decay measurement techniques will also be discussed. Introduction A family of computer-controlled test equipment has been developed for research, development and manufacturing quality control of the key components used in an electrophotographic system including the photoreceptor, charge roller and magnetic roller (Figure 1). This equipment is designed for rapid, high resolution scanning of a finished component for detailed characterization without any special specimen preparation. The results of the measurement include both electrophotographic properties and mappings of physical and electrical defects. The systems are designed to be very versatile, flexible and easy to use. Photoreceptor (Drum or Belt) PDT-1000 PDT-2000 ECT-100 Erasure