Method of Calculating the Charge Acceptance of Organic Photoconductors

The charge acceptance of organic photoconductors (OPC) consisting of thin layers must attain the correct value in order to produce constant copy quality. In practice, however, it can be kept constant only by taking elaborate precautions, since a number of parameters have an adverse effect on charge acceptance. The limits are described within which the photoconductors and corona properties fluctuate in actual running machines. The properties of the photo-conductor can scarcely be influenced by the user, but proper choice of the electric parameters of the charging scorotron can largely suppress the influence of the fluctuations on the final charge of the photo-conductor. If the charging device exhibits the behavior of an ideal constant voltage supply characteristic, charge acceptance would depend solely on the tolerances of this device. If the charging device supplies constant current, charge acceptance depends primarily on the properties of the photoconductor. A careful estimate must be made to determine, under conditions as practical as possible, reasons for variations in charge acceptance. There are those caused by fluctuations in the charging device and those caused by fluctuations in the photoconductor. A mathematical method is described which makes it relatively simple to determine the actual OPC charge acceptance depending on application and variation of the electrical parameters.