Image forming apparatus

An image forming apparatus configured to perform an image forming operation, the image forming apparatus comprising:

• a rotatable image carrying member on which an electrostatic latent image is formed;
• a developing device including a developer carrying member, the developing device being configured to contain a developer including toner and carrier, the developer carrying member being configured to carry the developer for developing the electrostatic latent image formed on the image carrying member into a toner image;
• a transfer member to which the toner image carried by the image carrying member is transferred;
• a carrier collection device including a rotatable collection roller, a magnet, and a conductor member, the carrier collection device being configured to collect the carrier from the image carrying member, the collection roller being disposed facing the image carrying member, downstream of a development portion where the electrostatic latent image formed on the image carrying member is developed, and upstream of a transfer portion where the toner image carried by the image carrying member is transferred to the transfer member in a rotation direction of the image carrying member, the magnet being non-rotatably disposed inside the collection roller, the conductor member being disposed facing the collection roller;
• a first bias application unit configured to apply a first bias obtained by superimposing a direct-current voltage and an alternating-current voltage, to the collection roller;
• and
• a second bias application unit configured to apply a second bias including the direct-current voltage, to the conductor member,
• wherein, during the image forming operation, an alternating-current electric field is formed between the collection roller to which the first bias is applied and the conductor member to which the second bias is applied.