Abstract: A document reading apparatus has a first scanning unit that can scan in a document conveyance direction and determines a document reading position, and a guide plate provided in a position that sandwiches the document being conveyed with the first scanning unit. On a facing surface of the guide plate relative to the first scanning unit, a first color section to which a white sheet is attached and a second color section having a sheet metal color (e.g. gray) of the guide plate are formed in the document conveyance direction. The document reading position corresponds to a position facing the second color section when a document is read in a crop mode.

Abstract: An image reader used as a back surface reading unit includes LEDs, a first mirror, a second mirror, a third mirror, a lens, and a CCD inside a housing. The first mirror, which first reflects light reflected from the document, is positioned farther away from the document reading position than other reflecting mirrors (i.e. the second mirror and the third mirror) in an optical axis direction of the optical path connecting the document reading position and the first mirror.

Abstract: A document reading apparatus has a first scanning unit that can scan in a document conveyance direction and determines a document reading position, and a guide plate provided in a position that sandwiches the document being conveyed with the first scanning unit. On a facing surface of the guide plate relative to the first scanning unit, a first color section to which a white sheet is attached and a second color section having a sheet metal color (e.g. gray) of the guide plate are formed in the document conveyance direction. The document reading position corresponds to a position facing the second color section when a document is read in a crop mode.

Abstract: To provide an optical scanning device including a lower housing including an opened top part, an upper housing that covers the top part of the lower housing, a rotating polygon mirror that reflects a beam, an f? lens on which the beam reflected by the rotating polygon mirror is incident, and a reflection mirror that reflects the beam. The lower housing is provided with a bottom surface opening including an opened bottom surface between the rotating polygon mirror and the reflection mirror.

Abstract: In an image reading device including a document platen, a document holder, multiple light sources, and a close contact type image sensor, the light sources are sequentially turned on and the image sensor individually reads light of multiple different colors reflected from a document in a main scanning direction. When the document holder is opened, in an area determination process, a first scanning area where a difference between output values of the image sensor when the light sources are sequentially turned on is within a predetermined threshold value range, and a second scanning area where the difference is outside the predetermined threshold value range are determined in an entire scanning area of the image sensor. A document size in the main scanning direction is detected based on a position of a boundary in the main scanning direction between the first and second scanning areas determined in the area determination process.

Abstract: An image reader used as a back surface reading unit includes LEDs, a first mirror, a second mirror, a third mirror, a lens, and a CCD inside a housing. The first mirror, which first reflects light reflected from the document, is positioned farther away from the document reading position than other reflecting mirrors (i.e. the second mirror and the third mirror) in an optical axis direction of the optical path connecting the document reading position and the first mirror.

Abstract: In an image reading device including a document platen, a document holder, multiple light sources, and a close contact type image sensor, the light sources are sequentially turned on and the image sensor individually reads light of multiple different colors reflected from a document in a main scanning direction. When the document holder is opened, in an area determination process, a first scanning area where a difference between output values of the image sensor when the light sources are sequentially turned on is within a predetermined threshold value range, and a second scanning area where the difference is outside the predetermined threshold value range are determined in an entire scanning area of the image sensor. A document size in the main scanning direction is detected based on a position of a boundary in the main scanning direction between the first and second scanning areas determined in the area determination process.

Abstract: To provide an optical scanning device including a lower housing including an opened upper part, an upper housing that covers the upper part of the lower housing, and an f? lens on which a beam reflected by a rotating polygon mirror is incident. The lower housing includes a raised area being raised upward from a lower housing bottom surface. The f? lens is mounted to face a bottom side of the raised area.

Abstract: An optical scanning device includes: a polygon mirror deflecting light beams; and a plurality of reflective mirrors reflecting the light beams so as to guide the light beams to respective photosensitive drums. A first f? lens is provided on an optical path of the light beam from the polygon mirror to a first reflective mirror. The optical path of the light beam reflected by a third reflective mirror crosses the optical path between the first reflective mirror and a second reflective mirror.

Abstract: An optical scanning device includes: a polygon mirror deflecting light beams; and a plurality of reflective mirrors reflecting the light beams so as to guide the light beams to respective photosensitive drums. A first f? lens is provided on an optical path of the light beam from the polygon mirror to a first reflective mirror. The optical path of the light beam reflected by a third reflective mirror crosses the optical path between the first reflective mirror and a second reflective mirror.

Abstract: To provide an optical scanning device including a lower housing including an opened upper part, an upper housing that covers the upper part of the lower housing, and an f? lens on which a beam reflected by a rotating polygon mirror is incident. The lower housing includes a raised area being raised upward from a lower housing bottom surface. The f? lens is mounted to face a bottom side of the raised area.

Abstract: To provide an optical scanning device including a lower housing including an opened top part, an upper housing that covers the top part of the lower housing, a rotating polygon mirror that reflects a beam, an f? lens on which the beam reflected by the rotating polygon mirror is incident, and a reflection mirror that reflects the beam. The lower housing is provided with a bottom surface opening including an opened bottom surface between the rotating polygon mirror and the reflection mirror.