A dual-axle linkage detection structure includes a first object, a second object, a sensor body, and a shielding element. The first object is movably connected to a base. The second object is movably connected to the first object. The sensor body is disposed on the first object and includes detecting positions. The shielding element includes a shielding part. When the second object covers the first object and the first object covers the base, the shielding part moves into the detecting position. When the second object moves away from the first object, or when the first object moves away from the base and drives the shielding element to rotate, the shielding part moves out of the detecting position.

An image reading device includes a first image reading portion, a cooling portion, a second image reading portion, and a notification processing portion. The first image reading portion reads an image of a document sheet at a first reading position. The cooling portion cools the document sheet at a cooling position downstream in a feeding direction of the document sheet with respect to the first reading position. The second image reading portion reads an image of the document sheet at a second reading position downstream in the feeding direction with respect to the cooling position. In a case where a difference image different from a first image read by the first image reading portion, the difference image being included in a second image read by the second image reading portion has been detected, the notification processing portion provides a notification that the difference image has been detected.

An image forming apparatus includes: a halftone processing unit configured to perform halftone processing on image data by a dither matrix that includes a plurality of submatrices and decide an exposure region of an image. In at least one of a first dither matrix corresponding to a first section, and a second dither matrix corresponding to a second section adjacent to the first dither matrix in the main scanning direction and corresponding to a second section different from the first section in tone value, at least a size of an exposure region of an image formed by using a first submatrix corresponding to a predetermined tone value in the dither matrix and a size of an exposure region of an image formed by using a second submatrix corresponding to the predetermined tone value are different.

A method and system of controlling at least one printbar in a printing system are described. The printing system has one or more of printbars distributed along a media transport. A first image including a reference pattern is generated on a print medium with a first printbar. A pattern is then detected on the print medium. The reference pattern and the detected pattern are used to determine a position of the first image relative to a second printbar. This position is used to configure nozzle data for a second image to be generated on the print medium by the second printbar.

A light scanning device includes: a first semiconductor laser 44a that emits a light beam L1; a polygonal mirror 42 that deflects the light beam L1; a reflective mirror 64a that reflects the light beam L1 deflected by the polygonal mirror 42 and causes the light beam L1 to enter a photosensitive drum 13; and a BD sensor 72 that detects the light beam L1 deflected by the polygonal mirror 42. The light scanning device scans the photosensitive drum 13 with the light beam L1 and set scanning timing of the photosensitive drum 13 using the light beam L1 based on detection timing of the light beam L1 using the BD sensor 72. The BD sensor 72 is arranged in the position farther from the polygonal mirror 42 than the last reflective mirror 64a that reflects the light beam L1 immediately before entering the photosensitive drum 13 and arranged inside a scanning angle range of the light beam L1 corresponding to an effective scan area of the photosensitive drum 13.

A dual-axle linkage detection structure includes a first object, a second object, a sensor body, and a shielding element. The first object is movably connected to a base. The second object is movably connected to the first object. The sensor body is disposed on the first object and includes detecting positions. The shielding element includes a shielding part. When the second object covers the first object and the first object covers the base, the shielding part moves into the detecting position. When the second object moves away from the first object, or when the first object moves away from the base and drives the shielding element to rotate, the shielding part moves out of the detecting position.

A printer (300) is disclosed. The printer has two scanners (336, 338) in the paper path of the printer located after the print zone (346). The two scanners are spaced apart from each other by a known distance A and overlap each other in a direction perpendicular to the media axis of travel. The two scanners capture a first and second image of the media.

An image forming apparatus includes: a halftone processing unit configured to perform halftone processing on image data by a dither matrix that includes a plurality of submatrices and decide an exposure region of an image. In at least one of a first dither matrix corresponding to a first section, and a second dither matrix corresponding to a second section adjacent to the first dither matrix in the main scanning direction and corresponding to a second section different from the first section in tone value, at least a size of an exposure region of an image formed by using a first submatrix corresponding to a predetermined tone value in the dither matrix and a size of an exposure region of an image formed by using a second submatrix corresponding to the predetermined tone value are different.

A light scanning device includes: a first semiconductor laser 44a that emits a light beam L1; a polygonal mirror 42 that deflects the light beam L1; a reflective mirror 64a that reflects the light beam L1 deflected by the polygonal mirror 42 and causes the light beam L1 to enter a photosensitive drum 13; and a BD sensor 72 that detects the light beam L1 deflected by the polygonal mirror 42. The light scanning device scans the photosensitive drum 13 with the light beam L1 and set scanning timing of the photosensitive drum 13 using the light beam L1 based on detection timing of the light beam L1 using the BD sensor 72. The BD sensor 72 is arranged in the position farther from the polygonal mirror 42 than the last reflective mirror 64a that reflects the light beam L1 immediately before entering the photosensitive drum 13 and arranged inside a scanning angle range of the light beam L1 corresponding to an effective scan area of the photosensitive drum 13.

An image-reading apparatus includes: a light-receiving unit that receives reflected light from a recording medium; a substrate that supports the light-receiving unit; an optical member that is located at a position different from a position of the substrate in a substrate thickness direction corresponding to a thickness direction of the substrate and that guides the reflected light from the recording medium to the light-receiving unit; and a supply unit that supplies cooling gas that is used to cool the substrate to the substrate. The cooling gas that is supplied to the substrate flows along the substrate.