Abstract: An image forming apparatus includes a toner pattern bearer to bear a first toner pattern having a first image area and a second toner pattern having a second image area different from the first image area. A toner adhesion amount detector detects a toner adhesion amount of toner of each of the first toner pattern and the second toner pattern. A toner degradation rate calculator calculates a first deviation in the toner adhesion amount of the first toner pattern and a second deviation in the toner adhesion amount of the second toner pattern based on the toner adhesion amount detected by the toner adhesion amount detector. The toner degradation rate calculator compares the first deviation with the second deviation and calculates a toner degradation rate based on a comparison result.

Abstract: An image forming apparatus includes a toner pattern bearer to bear a first toner pattern having a first image area rate and a second toner pattern having a second image area rate different from the first image area rate. A toner adhesion amount detector detects a toner adhesion amount of toner of each of the first toner pattern and the second toner pattern. A toner degradation rate calculator calculates a first deviation in the toner adhesion amount of the first toner pattern and a second deviation in the toner adhesion amount of the second toner pattern based on the toner adhesion amount detected by the toner adhesion amount detector. The toner degradation rate calculator compares the first deviation with the second deviation and calculates a toner degradation rate based on a comparison result.

Abstract: A light-scanning device includes a polygon scanner having a rotatable polygon mirror which deflects a laser beam emitted from a light source, an optical image-forming element which images the deflected laser beam on a predetermined position, and an optical housing which supports the light source, the polygon scanner and the optical image-forming element, a non-rotational cylindrical shielding member for covering an upper part of the polygon scanner.

Abstract: An optical scanning device includes an optical housing in which a polygon mirror that is rotated by a motor is accommodated and an air inlet that includes a filter. An airflow guiding member is arranged at a position opposite to a surface of the polygon mirror on the air inlet side. An air inducing path is provided, which includes a first flowing path and a second flowing path. The first flowing path includes a first end linked to the air inlet and a second end arranged close to a mirror surface of the polygon mirror. The second flowing path is formed with a surface of the airflow guiding member on an opposite side of the air inlet and a top surface of the polygon mirror.

Abstract: An optical scanner includes a housing and an intermediate member that includes a first joining surface and a second joining surface. The first joining surface is attached to the housing and the second joining surface is attached to at least one optical element of any one of a first optical system and a second optical system. In a three-dimensional coordinate in which a first one of coordinate axes is a direction that is parallel to both the first joining surface and the second joining surface, a second range on the first coordinate axis corresponding to the second joining surface includes a center point of a first range on the first coordinate axis corresponding to the first joining surface.

Abstract: An optical scanning device that uses a light spot to scan an image surface with a light source, a deflector, and an imaging element includes a housing in which the light source, the deflector, and the imaging element are set. The housing includes at least two sidewalls opposed to each other, a bottom surface that extends substantially perpendicular to the sidewalls, and ribs that are substantially perpendicular to the bottom surface and formed to extend from the two sidewalls, respectively. Discontinuous sections (sections between ribs or notched sections of the ribs) for passing light beams are provided in the ribs. A reinforcing member separate from the ribs are bridged to the discontinuous sections.

Abstract: An optical scanning device includes a light source, a deflector that deflects a light beam from the light source, a first optical system that guides the light beam to the deflector, a second optical system that guides the light beam from the deflector to a surface to be scanned, and a housing that holds the light source and the deflector. At least one optical element included in the first optical system or the second optical system is attached to the housing via an intermediate member. The optical element is adjustable with respect to the intermediate member. The number of directions in which the optical element can be adjusted is two or more.

Abstract: A disclosed optical scanner includes a light source, a deflector that deflects a light beam emitted by the light source, a scanning imaging element that images and scans the deflected light beam as a light spot on an imaging surface, and an optical box that contains at least the deflector and the scanning imaging element and that is substantially sealed from outside. The deflector is substantially sealed so as to be substantially insulated from the scanning imaging element in the optical box. Among outer walls of the optical box insulating a space inside the optical box from the outside, at least an outer wall positioned above the deflector includes an upside-down U-shaped cross-sectional shape portion.

Abstract: An optical scanning device that uses a light spot to scan an image surface with a light source, a deflector, and an imaging element includes a housing in which the light source, the deflector, and the imaging element are set. The housing includes at least two sidewalls opposed to each other, a bottom surface that extends substantially perpendicular to the sidewalls, and ribs that are substantially perpendicular to the bottom surface and formed to extend from the two sidewalls, respectively. Discontinuous sections (sections between ribs or notched sections of the ribs) for passing light beams are provided in the ribs. A reinforcing member separate from the ribs are bridged to the discontinuous sections.

Abstract: An optical scanning device includes an optical housing in which a polygon mirror that is rotated by a motor is accommodated and an air inlet that includes a filter. An airflow guiding member is arranged at a position opposite to a surface of the polygon mirror on the air inlet side. An air inducing path is provided, which includes a first flowing path and a second flowing path. The first flowing path includes a first end linked to the air inlet and a second end arranged close to a mirror surface of the polygon mirror. The second flowing path is formed with a surface of the airflow guiding member on an opposite side of the air inlet and a top surface of the polygon mirror.

Abstract: A light-scanning device includes a polygon scanner having a rotatable polygon mirror which deflects a laser beam emitted from a light source, an optical image-forming element which images the deflected laser beam on a predetermined position, and an optical housing which supports the light source, the polygon scanner and the optical image-forming element, a non-rotational cylindrical shielding member for covering an upper part of the polygon scanner.

Abstract: An optical scanner includes a housing and an intermediate member that includes a first joining surface and a second joining surface. The first joining surface is attached to the housing and the second joining surface is attached to at least one optical element of any one of a first optical system and a second optical system. In a three-dimensional coordinate in which a first one of coordinate axes is a direction that is parallel to both the first joining surface and the second joining surface, a second range on the first coordinate axis corresponding to the second joining surface includes a center point of a first range on the first coordinate axis corresponding to the first joining surface.

Abstract: An optical scanner has light source units spaced from each other along a first direction and having optical axes parallel to each other. Positions from which the light beams are emitted are spaced from each other by a predetermined distance at least along a predetermined direction. The optical scanner also includes a deflection unit that deflects the light beams together and scans the light beams along a second direction perpendicular to the first direction. The optical scanner also has imaging units that form an image with each of the light beams on a surface and a housing unit that holds the light source units, the deflection units, and the imaging units.

Abstract: Light source and light beam scanning units with reduced deviation of beam positions over time and ambient conditions, in use for image forming apparatuses. In the light source unit for emanating light beams, including a plurality of LEDs and coupling lenses each corresponding to the LEDs, there are provided lens holders having two supporting faces aligned approximately parallel to the optical axes of the coupling lenses, elastic members for abutting the coupling lenses by pressing the side portions thereof onto the supporting faces, light source support members for holding LEDs corresponding to the coupling lenses, and bolts for fixing the light source support members. Following the proper adjustment of the position of the lens holder in the vertical direction with respect to the optical axes of the coupling lenses, the light source support members is fixed onto lens holder by bolts.

Abstract: A disclosed optical scanner includes a light source, a deflector that deflects a light beam emitted by the light source, a scanning imaging element that images and scans the deflected light beam as a light spot on an imaging surface, and an optical box that contains at least the deflector and the scanning imaging element and that is substantially sealed from outside. The deflector is substantially sealed so as to be substantially insulated from the scanning imaging element in the optical box. Among outer walls of the optical box insulating a space inside the optical box from the outside, at least an outer wall positioned above the deflector includes an upside-down U-shaped cross-sectional shape portion.

Abstract: An optical scanning device includes a light source, a deflector that deflects a light beam from the light source, a first optical system that guides the light beam to the deflector, a second optical system that guides the light beam from the deflector to a surface to be scanned, and a housing that holds the light source and the deflector. At least one optical element included in the first optical system or the second optical system is attached to the housing via an intermediate member. The optical element is adjustable with respect to the intermediate member. The number of directions in which the optical element can be adjusted is two or more.

Abstract: An optical scanning device that uses a light spot to scan an image surface with a light source, a deflector, and an imaging element includes a housing in which the light source, the deflector, and the imaging element are set. The housing includes at least two sidewalls opposed to each other, a bottom surface that extends substantially perpendicular to the sidewalls, and ribs that are substantially perpendicular to the bottom surface and formed to extend from the two sidewalls, respectively. Discontinuous sections (sections between ribs or notched sections of the ribs) for passing light beams are provided in the ribs. A reinforcing member separate from the ribs are bridged to the discontinuous sections.

Abstract: An optical scanning apparatus includes light sources, an aperture having, and coupling lenses. Numbers of the light sources and the coupling lenses are equal to each other and the apparatus satisfies an inequality 12.7<(D×?0×m0×dpi)/(2×NA)<38.1 and an equation ?0=(?+???)/(n?1), wherein D represents a width of the slit of the aperture, ?0 represents a beam open angle, mo represents a total lateral magnification ratio, dpi represents a number of dots per inch, NA represents a numerical aperture, ?+ represents a positive open angle, ?? represents a negative open angle, and n represents the number. Further, an image forming apparatus using this optical scanning apparatus and an image forming method are provided.

Abstract: An optical scanning apparatus includes light sources, an aperture having, and coupling lenses. Numbers of the light sources and the coupling lenses are equal to each other and the apparatus satisfies an inequality 12.7 <(D×?0×m0×xdpi)/(2×NA) <38.1 and an equation ?0=(?+???)/(n?1), wherein D represents a width of the slit of the aperture, ?0represents a beam open angle, mo represents a total lateral magnification ratio, dpi represents a number of dots per inch, NA represents a numerical aperture, ?+ represents a positive open angle, ?? represents a negative open angle, and n represents the number. Further, an image forming apparatus using this optical scanning apparatus and an image forming method are provided.

Abstract: An optical scanner has light source units spaced from each other along a first direction and having optical axes parallel to each other. Positions from which the light beams are emitted are spaced from each other by a predetermined distance at least along a predetermined direction. The optical scanner also includes a deflection unit that deflects the light beams together and scans the light beams along a second direction perpendicular to the first direction. The optical scanner also has imaging units that form an image with each of the light beams on a surface and a housing unit that holds the light source units, the deflection units, and the imaging units.