An image forming apparatus includes a rotatable photosensitive drum, a charging apparatus to which a charging voltage is applied, an exposure apparatus forming an electrostatic image, a developing apparatus to which a development voltage is applied, a timer measuring an image formation time lapsed from...http://www.google.es/patents/US7941062?utm_source=gb-gplus-sharePatente US7941062 - Image forming apparatus to control an image forming condition
Image forming apparatus to control an image forming condition
