Patent ID: 8175504
Filing Date: 2012-05-08
Classification: G03G

Abstract:
1. An image forming apparatus comprising: an image carrier that carries an electrostatic latent image on a surface thereof; a toner carrying roller that is disposed to face the image carrier and rotates in a predetermined rotation direction with charged toner carried on a surface thereof so as to transport the toner in an opposing position for facing the image carrier; and a bias applying unit that develops the electrostatic latent image with the toner by applying an AC voltage as a developing bias to the toner carrying roller, wherein periodical concavo-convexes that are formed of a plurality of convex portions arranged at a constant pitch in a circumferential direction and concave portions that surround the plurality of convex portions are formed on the surface of the toner carrying roller, and wherein, when the arrangement pitch is denoted by P, the frequency of the developing bias is denoted by F, and the moving speed of the surface of the toner carrying roller for the circumferential direction is denoted by V, a quotient acquired from dividing V by F is a value acquired from multiplying P by a natural number.