Abstract: An optical scanning apparatus includes first and second light sources, a rotatable polygonal mirror, a motor, first and second mirrors, first and second lenses, and a casing. Within a mounting range, a top wall of an accommodating portion is provided with at least one projection projecting toward an opening of the accommodating portion. The projection extends from a first side wall to a second side wall of the accommodating portion. The top wall includes a recess formed opposite from the projection, and is free from a portion projecting toward the opening over a range from the first side wall to the second side wall, other than the projection in the mounting range. A free end portion of the projection is in a position remoter from the opening than a reflecting surface of the rotatable polygonal mirror is with respect to a rotational axis direction of the motor.

Abstract: An optical scanning device includes a casing including a bottom portion on which the deflector is disposed and a side wall stood from the bottom portion, a circuit board, a cover closing an opening, formed by the side wall, of the casing. The side wall includes first and second side walls, and the second side wall includes a through hole, and first and second side surfaces of the through hole. The cover includes a protective portion for protecting the circuit board and a restricted portion disposed in a position corresponding to the through hole and including first and second end portions. The restricted portion includes first and second insertion portions to be inserted into the through hole. A distance between the second end portion and the second side surface is smaller than a distance between the protective portion and the closest electric element.

Abstract: An optical scanning device includes a light source, a rotatable polygon mirror, an optical member, an output portion and a detector. The optical member guides the luminous flux scanned by the rotatable polygon mirror to an image bearing member. The output portion is provided on an upstream side of the optical member in the scanning direction and outputs a signal corresponding to receiving the luminous flux. The detector is provided on the upstream side of the output portion and detects a light quantity of the luminous flux. A controller controls the light source based on the signal outputted from the output portion and the light quantity detected by the detector. The luminous flux reaching the detector is reflected at a position closer to an end portion of a reflecting surface of the rotatable polygon mirror in the main scanning direction than the luminous flux reaching the output portion.

Abstract: An image forming apparatus includes a plurality of photosensitive members; a scanner unit including light sources, a rotatable polygonal mirror, and reflecting members; and a fixing portion. Parts of the laser beams emitted from the light sources are reflected by the rotatable polygonal mirror toward the fixing device side, and rest parts of the laser beams are reflected by the rotatable polygonal mirror toward a side opposite from the fixing device side. Of the parts of the laser beams reflected by the rotatable polygonal mirror toward the fixing device side, the laser beam reflected toward the reflecting member provided at a position remotest from the rotatable polygonal mirror travels downward relative to a horizontal direction. A rotational axis of the rotatable polygonal mirror is inclined relative to a vertical direction.

Abstract: An image forming apparatus includes a plurality of photosensitive members; a scanner unit including light sources, a rotatable polygonal mirror, and reflecting members; and a fixing portion. Parts of the laser beams emitted from the light sources are reflected by the rotatable polygonal mirror toward the fixing device side, and rest parts of the laser beams are reflected by the rotatable polygonal mirror toward a side opposite from the fixing device side. Of the parts of the laser beams reflected by the rotatable polygonal mirror toward the fixing device side, the laser beam reflected toward the reflecting member provided at a position remotest from the rotatable polygonal mirror travels downward relative to a horizontal direction. A rotational axis of the rotatable polygonal mirror is inclined relative to a vertical direction.

Abstract: An optical scanning apparatus includes first and second light sources, a rotatable polygonal mirror, a motor, first and second mirrors, first and second lenses, and a casing. Within a mounting range, a top wall of an accommodating portion is provided with at least one projection projecting toward an opening of the accommodating portion. The projection extends from a first side wall to a second side wall of the accommodating portion. The top wall includes a recess formed opposite from the projection, and is free from a portion projecting toward the opening over a range from the first side wall to the second side wall, other than the projection in the mounting range. A free end portion of the projection is in a position remoter from the opening than a reflecting surface of the rotatable polygonal mirror is with respect to a rotational axis direction of the motor.

Abstract: An optical scanning apparatus includes first and second light sources, a rotatable polygonal mirror, a motor, first and second mirrors, first and second lenses, and a casing. Within a mounting range, a top wall of an accommodating portion is provided with at least one projection projecting toward an opening of the accommodating portion. The projection extends from a first side wall to a second side wall of the accommodating portion. The top wall includes a recess formed opposite from the projection, and is free from a portion projecting toward the opening over a range from the first side wall to the second side wall, other than the projection in the mounting range. A free end portion of the projection is in a position remoter from the opening than a reflecting surface of the rotatable polygonal mirror is with respect to a rotational axis direction of the motor.

Abstract: An image forming apparatus to form a toner image on a recording material includes a photosensitive member and an optical scanning unit. The optical scanning unit includes an optical scanning unit, an optical box, a cover member, and a moving unit movable to an outside of the image forming apparatus. The optical scanning unit and the moving unit are arranged so that the moving unit and the optical scanning unit are opposed to each other when the moving unit is located in an inside of the image forming apparatus. The optical scanning unit is disposed so as to allow a user to touch the optical scanning unit through a space generated in the inside of the image forming apparatus when the moving unit is moved to the outside of the image forming apparatus. Between the optical box and the cover member, the cover member is opposed to the moving unit.

Abstract: An image forming apparatus includes a plurality of photosensitive members; a scanner unit including light sources, a rotatable polygonal mirror, and reflecting members; and a fixing portion. Parts of the laser beams emitted from the light sources are reflected by the rotatable polygonal mirror toward the fixing device side, and rest parts of the laser beams are reflected by the rotatable polygonal mirror toward a side opposite from the fixing device side. Of the parts of the laser beams reflected by the rotatable polygonal mirror toward the fixing device side, the laser beam reflected toward the reflecting member provided at a position remotest from the rotatable polygonal mirror travels downward relative to a horizontal direction. A rotational axis of the rotatable polygonal mirror is inclined relative to a vertical direction.

Abstract: An image forming apparatus to form a toner image on a recording material includes a photosensitive member and an optical scanning unit. The optical scanning unit includes an optical scanning unit, an optical box, a cover member, and a moving unit movable to an outside of the image forming apparatus. The optical scanning unit and the moving unit are arranged so that the moving unit and the optical scanning unit are opposed to each other when the moving unit is located in an inside of the image forming apparatus. The optical scanning unit is disposed so as to allow a user to touch the optical scanning unit through a space generated in the inside of the image forming apparatus when the moving unit is moved to the outside of the image forming apparatus. Between the optical box and the cover member, the cover member is opposed to the moving unit.

Abstract: An image forming apparatus includes plural photosensitive members, a scanner unit for scanning the photosensitive members, and a fixing unit for fixing toner images. The scanner unit includes a rotatable polygonal mirror for reflecting laser beams emitted in correspondence to respective photosensitive members, reflecting members for reflecting the laser beams, and a box for accommodating the polygonal mirror and the reflecting members. The box includes plural outlets for the laser beams. Of the reflecting members, first and second reflecting members reflect laser beams toward corresponding first and second outlets respectively positioned farthest from and closest to the fixing unit.

Abstract: An image forming apparatus to form a toner image on a recording material includes a photosensitive member and an optical scanning unit. The optical scanning unit includes an optical scanning unit, an optical box, a cover member, and a moving unit movable to an outside of the image forming apparatus. The optical scanning unit and the moving unit are arranged so that the moving unit and the optical scanning unit are opposed to each other when the moving unit is located in an inside of the image forming apparatus. The optical scanning unit is disposed so as to allow a user to touch the optical scanning unit through a space generated in the inside of the image forming apparatus when the moving unit is moved to the outside of the image forming apparatus. Between the optical box and the cover member, the cover member is opposed to the moving unit.

Abstract: An image forming apparatus to form a toner image on a recording material includes a photosensitive member and an optical scanning unit. The optical scanning unit includes an optical scanning unit, an optical box, a cover member, and a moving unit movable to an outside of the image forming apparatus. The optical scanning unit and the moving unit are arranged so that the moving unit and the optical scanning unit are opposed to each other when the moving unit is located in an inside of the image forming apparatus. The optical scanning unit is disposed so as to allow a user to touch the optical scanning unit through a space generated in the inside of the image forming apparatus when the moving unit is moved to the outside of the image forming apparatus. Between the optical box and the cover member, the cover member is opposed to the moving unit.

Abstract: A laser marking method of performing marking by irradiating an object made of a resin with laser light, the laser marking method including: a first step of melting of carbonizing a first region of the object; and a second step of engraving a mark by irradiating a second region in the first region with the laser light.

Abstract: An image forming apparatus for forming an image in accordance with image information on a sheet includes a photosensitive member; a scanner unit for scanning the member with a laser beam in accordance with the information, the scanner unit including a source for emitting the beam, a deflector having a polygonal mirror for reflecting the beam to deflect it, and a sensor for receiving the beam deflected by the deflector; a controller for controlling scanning start timing of the beam in response to an output of the sensor. A reference position of scanning lines of the beam in a sub-scan direction and a center position of a receipt surface of the sensor in the direction are deviated from each other. For all scanning lines by reflecting surfaces of the rotatable polygonal mirror, only parts, in the direction, of the scanning lines pass the receipt surface of the sensor.

Abstract: An image forming apparatus includes a plurality of photosensitive members; a scanner unit including light sources, a rotatable polygonal mirror, and reflecting members; and a fixing portion. Parts of the laser beams emitted from the light sources are reflected by the rotatable polygonal mirror toward the fixing device side, and rest parts of the laser beams are reflected by the rotatable polygonal mirror toward a side opposite from the fixing device side. Of the parts of the laser beams reflected by the rotatable polygonal mirror toward the fixing device side, the laser beam reflected toward the reflecting member provided at a position remotest from the rotatable polygonal mirror travels downward relative to a horizontal direction. A rotational axis of the rotatable polygonal mirror is inclined relative to a vertical direction.

Abstract: An optical scanning apparatus includes first and second light sources, a rotatable polygonal mirror, a motor, first and second mirrors, first and second lenses, and a casing. Within a mounting range, a top wall of an accommodating portion is provided with at least one projection projecting toward an opening of the accommodating portion. The projection extends from a first side wall to a second side wall of the accommodating portion. The top wall includes a recess formed opposite from the projection, and is free from a portion projecting toward the opening over a range from the first side wall to the second side wall, other than the projection in the mounting range. A free end portion of the projection is in a position remoter from the opening than a reflecting surface of the rotatable polygonal mirror is with respect to a rotational axis direction of the motor.

Abstract: An image forming apparatus includes a plurality of photosensitive members; a scanner unit which includes light sources, a rotatable polygonal mirror, and a plurality of reflecting members; a fixing unit; and a discharge tray. The scanner unit is provided between the plurality of photosensitive members and the discharge tray with respect to a vertical direction, and a rotational axis of the rotatable polygonal mirror is inclined relative to the vertical direction. Selected ones of the laser beams emitted from the light sources are reflected toward a side with the fixing unit, and remaining ones of the laser beams are reflected toward an opposite side. Of the selected ones of the laser beams, the laser beam reflected toward the reflecting member provided at a position remotest from the rotatable polygonal mirror travels downward relative to a horizontal direction.

Abstract: An image forming apparatus for forming an image in accordance with image information on a sheet includes a photosensitive member; a scanner unit for scanning the member with a laser beam in accordance with the information, the scanner unit including a source for emitting the beam, a deflector having a polygonal mirror for reflecting the beam to deflect it, and a sensor for receiving the beam deflected by the deflector; a controller for controlling scanning start timing of the beam in response to an output of the sensor. A reference position of scanning lines of the beam in a sub-scan direction and a center position of a receipt surface of the sensor in the direction are deviated from each other. For all scanning lines by reflecting surfaces of the rotatable polygonal mirror, only parts, in the direction, of the scanning lines pass the receipt surface of the sensor.

Abstract: In one embodiment, an optical scanning device includes a board and a light receiving member, the positional accuracy of which is improved. When a length in a scanning direction and a length in an intersection direction of a body portion of the light receiving member are denoted by Lx0 and Ly0, respectively, and a length in the scanning direction and a length in the intersection direction of a through-hole formed in the board are denoted by Lx1 and Ly1, respectively, the lengths Lx0, Ly0, Lx1, and Ly1 satisfy the following formula: (Lx1?Lx0)>(Ly1?Ly0).