Patent ID: 9066052
Filing Date: 2015-06-23
Classification: G03G,H04N

Abstract:
1. An image forming apparatus comprising: an image forming unit configured to form a measurement image on a sheet; a conveyance unit configured to convey the sheet; a measurement unit configured to irradiate light on the measurement image and measure reflected light from the measurement image; a white reference plate provided to be movable to a first position opposite the measurement unit and to a second position that is further away from the measurement unit than the first position; a black member provided to be movable to a third position where the black member shields light that is irradiated on the white reference plate from the measurement unit and to a fourth position that is retracted from the third position, a guide unit provided at a position opposite the measurement unit and configured to be movable to a fifth position, where the guide unit guides the sheet to a side of the measurement unit and to a sixth position, that is further away from the measurement unit than the fifth position; and a control unit configured to, in a state in which the white reference plate is at the second position, the black member is at the third position, and the guide unit is at the fifth position, control the conveyance unit to convey the sheet between the measurement unit and the black member, and control the measurement unit to measure the measurement image, wherein the conveyance unit includes a first roller pair, provided upstream of the guide unit in a conveyance direction of the sheet, and a second roller pair, provided downstream of the guide unit in the conveyance direction of the sheet, and wherein while the guide unit is at the fifth position, a part of the sheet is closer to the measurement unit than a virtual plane connecting a first nip portion of the first roller pair and a second nip portion of the second roller pair.