Abstract: An image forming apparatus to form an image on a recording material includes a photosensitive member, an exposure device to form a latent image on the photosensitive member, a tubular body defining a space in which at least a part of the exposure device is contained, and a support portion that supports the exposure device and is provided along a rotation axis direction of the photosensitive member in the space of the tubular body. The image forming apparatus further includes, in the rotation axis direction, a first side plate fixed to one end portion of the tubular body, and a second side plate fixed to another end portion of the tubular body. One support portion end portion in the rotation axis direction is fixed to the first side plate, and another support portion end portion in the rotation axis direction is fixed to the second side plate.

Abstract: An image forming apparatus for forming an image on a recording material includes a photosensitive member; an optical scanning unit including a light source, an optical box, and a cover; and a fan. The fan is provided so that air from the fan directly impinges on the cover of the optical scanning unit. As seen in a direction perpendicular to a rotational axis of the rotatable polygonal mirror, a rib extending from a top plate of the cover toward an optical box side is provided at a portion of the cover in the neighborhood of a light beam emitting port of the optical scanning unit. The cover is provided with an extended portion extended from the rib in a light beam emitting direction.

Abstract: An image forming apparatus to form an image on a recording material includes a photosensitive member, an exposure device to form a latent image on the photosensitive member, a tubular body defining a space in which at least a part of the exposure device is contained, and a support portion that supports the exposure device and is provided along a rotation axis direction of the photosensitive member in the space of the tubular body. The image forming apparatus further includes, in the rotation axis direction, a first side plate fixed to one end portion of the tubular body, and a second side plate fixed to another end portion of the tubular body. One support portion end portion in the rotation axis direction is fixed to the first side plate, and another support portion end portion in the rotation axis direction is fixed to the second side plate.

Abstract: An image forming apparatus to form an image on a recording material includes a photosensitive member, an exposure device to form a latent image on the photosensitive member, a tubular body defining a space in which at least a part of the exposure device is contained, and a support portion that supports the exposure device and is provided along a rotation axis direction of the photosensitive member in the space of the tubular body. The image forming apparatus further includes, in the rotation axis direction, a first side plate fixed to one end portion of the tubular body, and a second side plate fixed to another end portion of the tubular body. One support portion end portion in the rotation axis direction is fixed to the first side plate, and another support portion end portion in the rotation axis direction is fixed to the second side plate.

Abstract: A scanning optical device includes a light source device, a rotational polygon mirror, a rotor which rotates together with the rotational polygon mirror, a stator which rotates the rotor, wherein a substrate for holding the stator includes a first regulation portion arranged so as to overlap with a portion of the rotor in a rotational axis direction of the rotor, and in a case where the rotor is caused to move in the rotational axis direction, the first regulation portion comes into contact with the rotor, and a second regulation portion is arranged in a position in relation with the first regulation portion so as to maintain the first regulation portion in a position where the first regulation portion overlaps with the portion of the rotor in the rotational axis direction, so as to regulate deformation of the first regulation portion.

Abstract: In an optical scanning device, an outer wall closest to a circumscribed circle of a rotating polygon mirror has a space in a position facing to a position of a reflection surface of the rotating polygon mirror in an axial direction of a rotating shaft. A part of a cover is provided in a position farther from the circumscribed circle than the outer wall so as to close the space, when the optical scanning device is viewed in a direction perpendicular to the axial direction of the rotating shaft.

Abstract: An image forming apparatus for forming an image on a recording material includes a photosensitive member; an optical scanning unit including a light source, an optical box, and a cover; and a fan. The fan is provided so that air from the fan directly impinges on the cover of the optical scanning unit. As seen in a direction perpendicular to a rotational axis of the rotatable polygonal mirror, a rib extending from a top plate of the cover toward an optical box side is provided at a portion of the cover in the neighborhood of a light beam emitting port of the optical scanning unit. The cover is provided with an extended portion extended from the rib in a light beam emitting direction.

Abstract: A rotary polygon mirror has no recess in a thickness region of one of the reflecting surfaces of the rotary polygon mirror in the direction of the rotation axis of the rotary polygon mirror and has a protruding portion protruding from the thickness region in a direction away from the thickness region.

Abstract: An image forming apparatus includes a photosensitive member and a scanning unit including a light source, a rotatable polygonal mirror, and a sensor. The image forming apparatus includes setting of an operation in a first mode and setting of an operation in a second mode. The image forming apparatus further comprises, a surface identifying portion and a correction data storing portion configured to prestore correction data including first correction data for a first rotational speed and second correction data for a second rotational speed. Positional deviation in a main scan direction of laser light is corrected on the basis of the first correction data or the second correction data.

Abstract: An optical scanning apparatus includes a deflector for deflecting a beam emitted from a light source, the deflector including a rotatable polygonal mirror for reflecting the beam, a motor for rotating the rotatable polygonal mirror, a substrate carrying the motor and provided with a circuit for driving the motor, and a magnetometric sensor carried on the substrate; an optical box accommodating the deflector. The substrate is provided with two holes for fastening the substrate to the optical box. The optical box is provided with two contact portion contacting the substrate in a state that the substrate is fastened to the optical box through the two holes. The magnetometric sensor is disposed at a position closer to a line m connecting the two holes than to a line n connecting two positions on the substrate where the two contact portions contact.

Abstract: A manufacturing method of a polygonal mirror using a metal mold including a first mold, a second mold, a third mold, and a fourth mold includes a step of forming the molded member by providing the third mold and the fourth mold between the first mold and the second mold in a state in which the third mold and the fourth mold are in contact with each other and then by injecting a resin material into the metal mold, and a step of separating the third mold from the first crossing surface of the molded member in a direction crossing the first crossing surface.

Abstract: A polygonal mirror includes a reflecting surface capable of reflecting laser light emitted from a light source, a base material made of a metal material, and a molded member molded outside the base material and including a first surface and a second surface which crosses the first surface and which corresponds to the reflecting surface.

Abstract: A polygonal mirror includes reflecting surfaces, a molded member including a first surface and a second surface, a contact portion, and gate marks. Each of said first surface and said second surface has a polygonal shape. The contact portion and the gate marks are formed at non-overlapping positions with a line segment connecting a vertex of the polygonal shape with a rotation center. The gate marks and the reflecting surfaces are the same in number. A perpendicular bisector of a line segment connecting centers of the gate marks adjacent to each other with respect to a rotational direction of the polygonal mirror is formed at a position passing through an associated vertex of the polygonal shape and the rotation center.

Abstract: A scanning optical device includes a light source device, a rotational polygon mirror, a rotor which rotates together with the rotational polygon mirror, a stator which rotates the rotor, wherein a substrate for holding the stator includes a first regulation portion arranged so as to overlap with a portion of the rotor in a rotational axis direction of the rotor, and in a case where the rotor is caused to move in the rotational axis direction, the first regulation portion comes into contact with the rotor, and a second regulation portion is arranged in a position in relation with the first regulation portion so as to maintain the first regulation portion in a position where the first regulation portion overlaps with the portion of the rotor in the rotational axis direction, so as to regulate deformation of the first regulation portion.

Abstract: An image-forming apparatus includes a light-irradiation unit configured to move a spot of laser light on a surface of a photosensitive member at a non-constant scanning velocity in a main scanning direction to form a latent image on the photosensitive member, an image data correcting unit configured to correct a length in the main scanning direction of image data by inserting one or more image data pieces into the image data, the number of the image data pieces increasing as the scanning velocity increases, and/or extracting one or more image data pieces from the image data, the number of the image data pieces increasing as the scanning velocity decreases, and a brightness correcting unit configured to correct a brightness of the laser light so that an emission brightness increases as the scanning velocity increases and/or the emission brightness decreases as the scanning velocity decreases.

Abstract: An image-forming apparatus includes a light-irradiation unit configured to move a spot of laser light on a surface of a photosensitive member at a non-constant scanning velocity in a main scanning direction to form a latent image on the photosensitive member, an image data correcting unit configured to correct a length in the main scanning direction of image data by inserting one or more image data pieces into the image data, the number of the image data pieces increasing as the scanning velocity increases, and/or extracting one or more image data pieces from the image data, the number of the image data pieces increasing as the scanning velocity decreases, and a brightness correcting unit configured to correct a brightness of the laser light so that an emission brightness increases as the scanning velocity increases and/or the emission brightness decreases as the scanning velocity decreases.

Abstract: An image-forming apparatus includes a light-irradiation unit configured to move a spot of laser light on a surface of a photosensitive member at a non-constant scanning velocity in a main scanning direction to form a latent image on the photosensitive member, an image data correcting unit configured to correct a length in the main scanning direction of image data by inserting one or more image data pieces into the image data, the number of the image data pieces increasing as the scanning velocity increases, and/or extracting one or more image data pieces from the image data, the number of the image data pieces increasing as the scanning velocity decreases, and a brightness correcting unit configured to correct a brightness of the laser light so that an emission brightness increases as the scanning velocity increases and/or the emission brightness decreases as the scanning velocity decreases.

Abstract: A light source device includes a light source configured to emit a laser beam; a lens through which the laser beam emitted from the light source passes; and a holder member for holding the light source and the lens; wherein the holder member is provided with an opening through which the laser beam is outputted; wherein the lens is bonded with the holder member at whole circumference of the opening by an adhesive material without contact with the holder member.

Abstract: An optical scanning apparatus includes a deflector for scanningly deflecting a beam; a scanning lens for imaging the beam deflected by the deflector on a surface; a casing for a light source, the deflector and the lens; and an elastic member urging the lens toward the casing along an optical axis. The lens is provided with an abutment at a beam emergent side of the lens, the abutment abutting to the casing, and is provided with a limiting portion at a side opposite from the emergent side, the limiting portion limiting movement in the opposite direction. The elastic member and the limiting portion limits the movement of the lens in the direction opposite to the direction of the lens. When the lens contacts a positioning portion of the casing, a gap is provided between the elastic member and the limiting portion with respect to the direction.

Abstract: An optical scanning apparatus includes a deflector for deflecting a beam emitted from a light source, the deflector including a rotatable polygonal mirror for reflecting the beam, a motor for rotating the rotatable polygonal mirror, a substrate carrying the motor and provided with a circuit for driving the motor, and a magnetometric sensor carried on the substrate; an optical box accommodating the deflector. The substrate is provided with two holes for fastening the substrate to the optical box. The optical box is provided with two contact portion contacting the substrate in a state that the substrate is fastened to the optical box through the two holes. The magnetometric sensor is disposed at a position closer to a line m connecting the two holes than to a line n connecting two positions on the substrate where the two contact portions contact.