Patent ID: 8380093

Claim:
An image forming apparatus comprising: a color shift pattern output unit to cause: a first transfer member, configured to develop a latent image formed on a photoreceptor by light exposure and transfer an unfixed image to a recording medium, to transfer a color shift correction pattern on a conveying belt to convey the recording medium; a second transfer member, arranged downstream of the first transfer member in the recording medium conveying direction, to transfer an unfixed image transferred to a first intermediate transfer member to the recording medium; and a third transfer member to transfer the color shift correction pattern to the first intermediate transfer member, a correction amount acquisition unit to obtain a correction amount when performing positional error correction in the sub-scanning direction between the unfixed image that the first transfer member transfers and the unfixed image that the second transfer member transfers, based on the color shift correction pattern transferred to the first intermediate transfer member from the conveying belt and the color shift correction pattern transferred to the first intermediate transfer member by the third transfer member; and a correction unit configured to correct at least one color shift error in the image in the recording medium among color shift errors in the sub-scanning direction occurring when the first transfer member transfers an unfixed image and when the second transfer member transfers an unfixed image.