Patent ID: 8693923

Claim:
A developing apparatus comprising: a developer carrier configured to carry developer including toner and carrier, and develop an electrostatic latent image at a development position; a developer container, which is separated to be segmented into a developing chamber for supplying the developer to the developer carrier, and a stirring chamber for collecting the developer to be stirred from the developer carrier, and in which a circulation path is formed to communicate with the developing chamber and the stirring chamber at their both ends to circulate the developer; and a conveyance unit provided in each of the developing chamber and the stirring chamber configured to convey and circulate the developer in the developing chamber and the stirring chamber, wherein an average surface roughness of an inner wall surface region of the developing chamber facing at least a developer carrying region of the developer carrier is smaller on an upstream side than on a downstream side with reference to a middle position of the development position in a direction of conveying the developer in the developing chamber.