Detecting and correcting for low developed mass per unit area

摘要

A method of maintaining consistent large solid area development by developing a large area test patch covering the image area of a photorececptor and detecting the lead edge and trail edge density of the test patch using a densitometer to measure reflectance and comparing the lead and trail edge density to the lead and trail edge density of a reference patch. The reference patch is generated after the changing of developer elements such as developer material and photoreceptor and an electrostatic set up performed. Alternatively a density differential between lead and trail edge density of the test patch is detected. Electrostatic parameters such as preset toner concentration control values and decreasing the development field of the test patch are adjusted to maintain constant large solid area development.