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US 2011/0255891 A1Published application
Image forming apparatus
AssigneeCanon Kabushiki Kaisha
InventorMasayuki Hirano
Life of this patent
Estimating the term…
Abstract
A first mark and a second mark are provided on a photosensitive drum and a rotation reference position sensor detects these marks. A counter is reset according to a detection signal corresponding to the first mark, and is incremented its count value according to a detection signal corresponding to the second mark. A CPU controls an exposure intensity based on light amount correction data read from a memory according to the counted value.
Claims10
An image forming apparatus comprising:
- a photosensitive member configured to be driven to rotate by a drive unit, wherein the photosensitive member includes a first mark and a plurality of second marks whose shape is different from a shape of the first mark, and the first mark and the plurality of second marks are disposed along the rotational direction of the photosensitive member;
- an exposure unit configured to perform exposure of the photosensitive member;
- a detection unit configured to detect the first mark and the plurality of second marks;
- a storage unit configured to store correction data corresponding to the first mark and the plurality of second marks;
- and
- a control unit configured to control an exposure intensity of the exposure unit based on the correction date corresponding to the first mark and the plurality of second marks in accordance with detection of the first mark by the detection unit and a count value of detecting the plurality of second marks after detecting the first mark by the detection unit.
3 more elements
An image forming apparatus comprising:
- a photosensitive member configured to be driven to rotate by a drive unit, wherein the photosensitive member includes a first mark and a plurality of second marks having a different light reflectance from a light reflectance of the first mark, and the first mark and the plurality of second marks are disposed along the rotational direction of the photosensitive member;
- an exposure unit configured to perform exposure of the photosensitive member;
- a detection unit configured to irradiate light to each of the plurality of second marks or the first mark, and output a detection signal according to a light amount of reflected light from each of the plurality of second marks or the first mark;
- a storage unit configured to store correction data corresponding to the first mark and each of the plurality of second marks;
- and
- a control unit configured to control an exposure intensity of the exposure unit according to the correction data corresponding to the first mark if the detection unit outputs the detection signal corresponding to the first mark, and control the exposure intensity according to the correction data based on the number of detection signal output from the detection unit after the detection of the first mark if the detection unit outputs the detection signal corresponding to any one of the plurality of second marks.
3 more elements
Dependencies are inferred from the claim text.