Abstract: An optical scanning device has an optical housing. A coupled Helmholtz resonator having a first resonance space and a second resonance space therein is disposed in the optical housing. A translucent partition wall, a first partition wall, and a second partition wall which extend from a bottom wall to a top wall of the optical housing are arranged in this order from an upstream side toward a downstream side on an optical path between a light source and a rotary polygonal mirror. The first and second resonance spaces are separated from each other by the three partition walls. One of the first and second resonance spaces resonates at a frequency of a rotational speed of a motor, and the other of the first and second resonance spaces resonates at a generated frequency of a wind noise generated by the rotary polygonal mirror.

Abstract: An information processing apparatus is configured to correctly detect a polygon face of a mirror being scanned even when noise occurs in a synchronization signal. The information processing apparatus is connected to an image forming apparatus including a laser light source configured to receive image data and output light; a photosensitive member; a polygon mirror, which has a plurality of reflection faces, and is configured to rotate to deflect a laser beam through use of the plurality of reflection faces, to thereby scan the photosensitive member; and a generator configured to generate a marking BD (beam detection) signal based on the deflected laser beam. The information processing apparatus receives a marking signal and determines whether or not the received marking signal is a signal corresponding to a specific reflection face among the reflection faces of the polygon mirror.

Abstract: An image forming unit includes a first receptor, a light source, a photosensitive member, a rotational polygon mirror, a light receiving unit, an identifier configured to identify a reflection face, and a generator. An information processing apparatus includes a second receptor, a first detector, a second detector, a determiner, a corrector configured to correct image data, and an output unit configured to output corrected image data to the image forming unit. When the first change is newly detected in a predetermined period, the determiner determines, based on a time period from the second timing at which the first change is newly detected to a timing at which the second change is detected and a time period from the first timing to a timing at which the second change is lastly detected before the second timing, whether the first change is a change corresponding to the identified reflection face.

Abstract: An image forming apparatus is provided with: an image forming unit having a photosensitive member, a charger, and a developer carrier, the image forming unit being configured to transfer the developer image to a recording sheet to form an image on the recording sheet; a motor configured to drive the photosensitive member and the developer carrier; a controller configured to control the motor and the charger, and a re-conveyance mechanism configured to reverse the recording sheet discharged from the image forming unit and to convey the recording sheet back towards the image forming unit. The controller is configured to turn off the charger after the motor is turned off, during a time period after the recording sheet is discharged from the image forming unit until the recording sheet is re-conveyed to the image forming unit by the re-conveyance mechanism.

Abstract: An optical scanning device that scans a target surface with light, includes: a light source; a deflector that deflects light of the light source; and an optical system that forms an image of light deflected, wherein the deflector includes: a polygon mirror that reflects and deflects light of the light source; a motor that rotates the polygon mirror; and a case body that airtightly houses the polygon mirror and the motor, the case body includes a cylindrical inner wall, and the inner wall includes a rectifier that guides, from one to the other of a first space and a second space, an air flow generated by rotation of the polygon mirror in a space surrounded by the inner wall, and the first space is located on the motor side with respect to the polygon mirror and the second space is located on an opposite side of the first space.

Abstract: An image forming apparatus capable of correcting light amounts of light beams which expose a photosensitive member with simple construction. The image forming apparatus includes a photosensitive drum, and a beam scanning device including a plurality of semiconductor lasers which emit light beams for exposing the photosensitive drum, and a memory which stores first correction data for correcting the light amount of each light beam in a manner associated with each of the plurality of semiconductor lasers. A CPU outputs second correction data for being commonly used in correcting the light amounts of the light beams emitted from the plurality of semiconductor lasers to the beam scanning device. A laser driver IC provided in the beam scanning device controls the light amount of the light beam emitted from each semiconductor laser based on the first correction data and the second correction data.

Abstract: An image processing apparatus, includes an image-scanning unit, and an image processing unit, wherein when the image-scanning unit continuously scans a plurality of documents, the image-scanning unit continuously scans the documents and parallel the image processing unit executes image processing on the scanned documents.

Abstract: An image forming apparatus includes an image forming portion for forming an image on a recording material; an image reading portion, for reading an original image, movable between a first position in which the image reading portion opposes the image forming portion and a second position in which the image reading portion is partly raised from the image forming portion; an openable member movable, relative to the image forming portion independently of the image reading portion, between an open position in which the openable member exposes an inside of the image forming portion and a closed position in which the openable member covers the image forming member; and preventing means capable of preventing movement of the openable member toward the closed position when the image reading member is located at the second position.

Abstract: An image reading device is provided, which includes a controller configured to, when a carriage reaches a turn-around position in a moving direction, control a motor to once stop, then rotate in a second direction opposite to a first direction such that a planetary gear swings to a position separated from an output gear and that an intermediate gear moves to an engagement position to engage with the output gear, and thereafter again rotate in the first direction so as to transmit a driving force from the motor to the output gear via an input gear, a planetary gear, and the intermediate gear.

Abstract: A scanning optical apparatus includes scanning units, a deflector. Each of the apparatuses includes a light source, an imaging optical system including imaging optical elements imaging a beam deflected by the deflector on a scanning surface. The scanning surfaces are scanned with beams in opposing directions. When a main scanning direction of the first scanning unit is a Y positive direction, a sign is the same between ?1h(Y1min)×?1r and ?2h(Y1min)×?2r. Here, ?1h(y), ?2h(y) denote orientation angles between the Y axis and a slow axis at a Y direction position y of first/second imaging optical elements from an optical axis, the imaging optical elements each being an imaging optical element having a largest thickness among them of the imaging optical systems, ?1r and ?2r denote angles between the Y axis and polarization directions of the beams reaching the imaging optical elements, and Y1min denotes a Y position where ?1h(y) becomes minimum.

Abstract: An image processing apparatus includes an image reading unit to read a plurality of different images from a single image at various focal distances, and an image processing unit to extract clear pixels from the read images to synthesize the extracted pixels. According to the apparatus and a method thereof, an image is scanned several times at various focal distances to extract pixels having a clear picture quality in each corresponding pixel or block, and a synthesized image including only the extracted pixels is generated, so that the construction of the image processing apparatus can be simplified and the manufacturing cost thereof can be minimized while a clear image is being obtained.

Abstract: A scanner including: a transparent plate; a light emitting unit that emits light to an object on the transparent plate; a sensor to form an image of the object; a focusing lens unit that is arranged on a light path between the transparent plate and the sensor, to focus light from the object onto the sensor; and a controller to determine whether a foreign substance is disposed in the light path, using the image, calculates a position of the foreign substance, and corrects the image on the basis of the calculated position of the foreign substance.

Abstract: An optical scanning apparatus, including: a light source unit; a deflection unit; an incident optical system; and an imaging optical system, wherein at least one optical surface of a plurality of imaging lenses included in an imaging optical system has a non-circular shape in a sub-scanning section perpendicular to a main scanning direction, and a non-circular amount of the non-circular shape changes along the main scanning direction, and wherein the followings are satisfied: ds(Y=0)<0; and ds(Y=Ymax)>0, where ds(Y=0) and ds(Y=Ymax) respectively represent a paraxial field curvature at a center position in a sub-scanning direction perpendicular to the main scanning direction and a paraxial field curvature in the sub-scanning direction at a maximum image height in an effective scanning range of the surface to be scanned by the beam from the light source unit in the main scanning direction, among field curvatures at a center position in the effective scanning range.

Abstract: A first main-scanning-position correction unit divides a surface to be scanned into first areas in a main scanning direction into areas, sets a separate clock-pulse timing for first area, and corrects a main-scanning position error. A second main-scanning-position correction unit divides the surface into second areas in the main scanning direction based on first-scanning-position correction data, sets a separate clock-pulse timing for each second area, and corrects the main-scanning position error.

Abstract: A scanning optical apparatus includes: an incident optical system which is disposed in an optical path between a light source unit and a deflection unit, and includes an optical element for making a light flux emitted from the light source unit enter a deflection surface of the deflection unit with an oblique angle in a sub scanning section; and a positional regulation member for holding the optical element having an x reference surface for performing positional regulation of the optical element in an optical axis direction and a z reference surface for performing positional regulation of the optical element in a sub scanning direction. The optical element is held by a casing so that the x reference surface and the z reference surface contact with the positional regulation member of the casing. The principal ray of the light flux outgoing from the optical element satisfies a conditional equation (1).

Abstract: Multiple images are combined where the images exhibit variations in illumination between one another. The images are of the same portion of an object, and each image is represented by a set of image data. A comparative data transform is applied to each set of image data, such that the transformed comparative image data isolates and preserves first variations in the illumination between the images but suppresses second differences in illumination between the images. At least one normalization transform is determined from the transformed comparative image data sets. When applied to at least one of the image data sets, the at least one normalization transform minimizes the variation in illumination between the image data sets. Each determined normalization transform is applied to the at least one of the image data sets. The normalized sets of image data are transformed to a single image of the portion of the object.

Abstract: A polygonal mirror, a light scanning unit using the polygonal mirror, and an image forming apparatus. The polygonal mirror is formed of a plastic and includes a plurality of reflection surfaces that are formed in an outer portion of the polygonal mirror and rotate around a rotational axis, and an internal mirror surface that defines a hole, wherein a ratio of an internal diameter d to an outer diameter D satisfies 0.1?d/D?0.3.

Abstract: An optical scanning device configured to remove or sufficiently reduce ghost light includes an input optical system for directing a light beam from a light source to a deflecting surface of a deflector, and an imaging optical system for imaging a light beam scanningly deflected by the deflecting surface upon a surface to be scanned, wherein, in a sub-scan section, the light beam is incident on the deflecting surface of the deflector from an oblique direction with respect to an optical axis of the imaging optical system, wherein a light blocking member for blocking ghost light is disposed on a light path between the deflecting surface and the scanned surface, wherein an end portion of the light blocking member in the sub-scan direction is formed with a curved shape having a height in the sub-scan direction which height changes in accordance with the position in the main-scan direction.

Abstract: A disclosed method of manufacturing a surface emitting laser includes laminating a transparent dielectric layer on an upper surface of a laminated body; forming a first resist pattern on an upper surface of the dielectric layer, the first resist pattern including a pattern defining an outer perimeter of a mesa structure and a pattern protecting a region corresponding to one of the relatively high reflection rate part and the relatively low reflection rate part included in an emitting region; etching the dielectric layer by using the first resist pattern as an etching mask; and forming a second resist pattern protecting a region corresponding to an entire emitting region. These steps are performed before the mesa structure is formed.

Abstract: An image scanner includes: a light source that irradiates, with light, a recording medium on which an image is formed; a light receiving portion that receives light reflected by the recording medium; and a reflecting portion that has a reflecting surface for measuring the amount of specular reflection light coming from the light source, the specular reflection light being included in the light received by the light receiving portion.

Abstract: An optical scanning device includes: a light source that emits light rays; an aperture member that adjusts a diameter of the light rays; a deflector including a plurality of reflecting surfaces that deflect the light rays; a scanning optical system that guides a light ray, of the light rays incident on the deflector and deflected by the deflector so as to be subjected to scanning onto a to-be-scanned surface; and a synchronization detector that performs synchronization detection by using a light ray, of the light rays, reflected to the aperture from the deflector is provided.

Abstract: A light scanning unit includes: a light source unit; a polygon mirror for deflecting and scanning light emitted from the light source unit, in a main scanning direction, and having a plurality of deflection surfaces and a plurality of edges at which adjacent deflection surfaces meet one another; an image forming optical system for condensing the deflected light; and a synchronization detection optical system for detecting a portion of light that is divided and reflected at an edge of the polygon mirror. The light scanning unit may be incorporated into an image forming apparatus.

Abstract: A scanning optical apparatus includes, for example, a determination unit, a correction unit, a creating unit, and a drive control unit. The determination unit determines an amount of correction of an image clock for controlling an output timing of a beam for each pixel constituting one line in a main scanning direction of the beam. The correction unit corrects the image clock in accordance with the amount of correction that is determined. The creating unit creates an image signal that is utilized for driving a light source in accordance with the image clock that is corrected. The drive control unit controls driving of the light source in accordance with the image signal.

Abstract: A surface-emitting laser device configured to emit laser light in a direction perpendicular to a substrate includes a p-side electrode surrounding an emitting area on an emitting surface to emit the laser light; and a transparent dielectric film formed on an outside area outside a center part of the emitting area and within the emitting area to lower a reflectance to be less than that of the center part. The outside area within the emitting area has shape anisotropy in two mutually perpendicular directions.

Abstract: An image forming apparatus includes a communicating unit (123) that performs communication with an-external apparatus (200), a recording unit (97) that stores image information, an image processing unit (96) that performs image processing, and a control unit (91) that performs control to secure the image processing unit from the external apparatus via the communicating unit, when a request signal for performing processing of the image information is received, if the image processing unit can be secured, convert a file format by expanding the image information and compressing the image information again using the image processing unit secured and transfer the image information converted via the communicating unit, and, if the image processing unit cannot be secured, transmit an indication that the image processing unit cannot be secured and the image information before the conversion to the external apparatus via the communicating unit.

Abstract: An optical scanning device includes a housing, a laser light source outputting a laser light, a polygon mirror arranged in an arrangement space and deflecting the laser light to scan a predetermined object with the laser light while rotating, a polygon motor rotating the polygon mirror, a control board arranged in the arrangement space and controlling the polygon motor, and a flow-control member arranged in the arrangement space and guiding an airflow generated by a rotation of the polygon mirror to an outside of the arrangement space to circulate the airflow within the housing.

Abstract: A scanning optical apparatus includes scanning units, a deflector. Each of the apparatuses includes a light source, an imaging optical system including imaging optical elements imaging a beam deflected by the deflector on a scanning surface. The scanning surfaces are scanned with beams in opposing directions. When a main scanning direction of the first scanning unit is a Y positive direction, a sign is the same between ?1h(Y1min)×?1r and ?2h(Y1min)×?2r. Here, ?1h(y), ?2h(y) denote orientation angles between the Y axis and a slow axis at a Y direction position y of first/second imaging optical elements from an optical axis, the imaging optical elements each being an imaging optical element having a largest thickness among them of the imaging optical systems, ?1r and ?2r denote angles between the Y axis and polarization directions of the beams reaching the imaging optical elements, and Y1min denotes a Y position where ?1h(y) becomes minimum.

Abstract: An optical scanning device includes a plurality of light sources, a light deflector, and a single scan lens. The light deflector deflects a plurality of light beams emitted from the light sources by a same face for scanning a plurality of to-be-scanned portions simultaneously. The single scan lens receives the light beams from the light deflector and focuses the light beams onto each of the plurality of to-be-scanned portions to scan the to-be-scanned portions simultaneously. The single scan lens is used in common for the light beams, and has one incidence plane and a plurality of exit planes in a sub-scanning direction separately prepared in the sub-scanning direction for each of the to-be-scanned portions. The incidence plane has a refractive power of the lens in the sub-scanning direction decreasing toward peripheral portions in the main scanning direction. The exit planes have positive refractive power in the main and sub-scanning directions.

Abstract: A light deflector device includes a light deflector having an oscillation system, a driving unit for driving the oscillation system and a drive controlling unit for supplying a drive signal. The oscillation system simultaneously generates a first oscillating motion of a first frequency and a second oscillating motion of a second frequency. The drive controlling unit supplies a drive signal formed by synthetically combining a first signal having the first frequency and a second signal having the second frequency to the driving unit and, at the same time, another drive signal for changing at least the amplitude of the first oscillating motion, the amplitude of second oscillating motion or the relative phase difference of the first oscillating motion and the second oscillating motion to the driving unit in order to correct an offset of scanning light deflected by the light deflector.

Abstract: A disclosed optical scanning device includes: a light source unit having plural luminous sources; a light source driving unit modulating each luminous source in accordance with pixel information; an oscillating mirror supported on a twist beam as a rotation shaft, the oscillating mirror collectively deflecting light beams from the luminous sources and performing reciprocating scanning on a surface to be scanned; an imaging optical system imaging the light beams from the luminous sources on the surface to be scanned; an oscillating mirror driving unit setting a scanning frequency f in accordance with a resonance frequency of the oscillating mirror; and a pitch adjustment unit adjusting beam spot intervals p in a sub-scanning direction in accordance with the scanning frequency f of the oscillating mirror that has been set.

Abstract: An image-forming device has a plurality of cylindrical image-carrying members, and an optical scanning unit. The plurality of cylindrical image-carrying members is provided in a main casing for rotating about respective rotational axes. The rotational axes are parallel to one another and juxtaposed in a single direction. The optical scanning unit is provided in the main casing and has a plurality of laser generators, a single rotatable polygon mirror, a plurality of mirrors, and a plurality of lenses. The plurality of laser generators is provided one-to-one relationship to the plurality of image-carrying members to emit respective laser beams. The single rotatable polygon mirror deflects the respective laser beams to scan the respective image-carrying members therewith. The plurality of mirrors is provided one-to-one relationship to the plurality of image-carrying members to guide the respective laser beams along respective optical paths to the respective image-carrying members.

Abstract: An optical scanning apparatus, including an incident system that allows a beam from the light source to enter to deflector; and an imaging system that images the beam deflected by the deflector on a scanning surface, in which the incident system includes a first and second systems, the first system includes first and second elements each having a positive power with rotational symmetry, the light source is positioned at a shorter distance from the front focus position of the first element, the first element is formed integrally as a unit, powers of the second element and the first system, magnifications within main and sub-scanning sections of entire system, and focus movement within the main and sub-scanning sections on the scanning surface when the second element is moved in the optical axis direction are appropriately set.

Abstract: An image forming apparatus includes a communicating unit (123) that performs communication with an external apparatus (200), a recording unit (97) that stores image information, an image processing unit (96) that performs image processing, and a control unit (91) that performs control to secure the image processing unit from the external apparatus via the communicating unit, when a request signal for performing processing of the image information is received, if the image processing unit can be secured, convert a file format by expanding the image information and compressing the image information again using the image processing unit secured and transfer the image information converted via the communicating unit, and, if the image processing unit cannot be secured, transmit an indication that the image processing unit cannot be secured and the image information before the conversion to the external apparatus via the communicating unit.

Abstract: An optical scanning apparatus includes a light source configured to emit a light beam, a rotational polygonal mirror configured to deflect and scan the light beam emitted from the light source, a drive unit configured to drive the rotational polygonal mirror to rotate, an optical member configured to guide the light beam with the scanning rotational polygonal mirror to a member to be scanned, a storage member configured to accommodate the rotational polygonal mirror and the optical member therewithin, and a wall configured to partition a space inside the storage member into a first space in which the rotational polygonal mirror is installed and a second space in which the optical member is installed, wherein the wall has an opening through which air can pass, and the opening is configured to pass the light beam reflected by the scanning rotational polygonal mirror, and the wall has a vent which is different from the opening and configured to send at least a part of the air that has passed through the opening,

Abstract: A coupling optical system that couples a light beam from a light source. A separation optical element on which the light beam is incident through the coupling optical system includes an opening through which a part of the light beam having a highest light intensity passes, and reflects other part of the light beam incident on a surrounding area of the opening as a monitoring light beam. A light shielding member includes at least one of a light shielding portion arranged on an optical path between the light source and the coupling optical system and a light shielding portion arranged on an optical path between the coupling optical system and the separation optical system.

Abstract: A scanning optical apparatus includes: an incident optical system which is disposed in an optical path between a light source unit and a deflection unit, and includes an optical element for making a light flux emitted from the light source unit enter a deflection surface of the deflection unit with an oblique angle in a sub scanning section; and a positional regulation member for holding the optical element having an x reference surface for performing positional regulation of the optical element in an optical axis direction and a z reference surface for performing positional regulation of the optical element in a sub scanning direction. The optical element is held by a casing so that the x reference surface and the z reference surface contact with the positional regulation member of the casing. The principal ray of the light flux outgoing from the optical element satisfies a conditional equation (1).

Abstract: A scanning optical device wherein, on the basis of positional information concerning a spacing in a main-scan direction between imaging positions of a plurality of light beams passed through resin-made imaging optical elements and detected by a photodetecting device and a spacing between the imaging positions in a sub-scan direction of the plurality of light beams, a focal shift direction and a focal shift amount in the main-scan direction as well as a focal shift direction and a focal shift amount in the sub-scan direction are determined, and wherein an optical element of an input optical system is moved in an optical axis direction based on the determination, to correct the focal shift in the main-scan direction and the focal shift in the sub-scan direction.

Abstract: Disclosed herein are a laser scanning unit and an image forming apparatus having the same. The laser scanning unit may include a polygon minor connected to a rotor of a driving motor, a member disposed opposite the rotor in the axial direction of a rotating shaft of the driving motor and a flux-reduction unit configured to reduce the flux of air or any other gas flowing in the space between the rotor and the member.

Abstract: An oscillator device including an oscillation system with oscillators and torsion springs, a driving member for driving the oscillation system, and a drive control member for supplying a driving signal to the driving member, the oscillation system having at least a first oscillation mode and a second oscillation mode, the second oscillation mode having an angular frequency approximately n-fold the angular frequency of the first oscillation mode where n is an integer, the driving member driving the oscillation system so that it simultaneously oscillates in the first and second oscillation modes, wherein a natural angular frequency calculating member calculates the natural angular frequency of the second oscillation mode based on an output signal from a photodetector, being outputted at a timing whereat the reflection light passes over the photodetector.

Abstract: A scanning optical apparatus includes, for example, a light source that outputs a light beam that has been pulse width modulated in accordance with input image data and a deflection unit that deflects the light beam so that the light beam scans the surface of an image carrier in the main scanning direction. The scanning optical apparatus furthermore includes a correction unit that corrects the pulse width and light amount applied to the light beam at each scanning position in the main scanning direction on the image carrier in accordance with focus error in the light beam at each scanning position.

Abstract: Provided are a light scanning unit and an image forming apparatus including the light scanning unit. The light scanning unit can include a source, a deflector, and an optical imaging system. The deflector can deflect the light generated by the source. The optical imaging system can form the deflected light into an image on a photosensitive medium and can have a first and second optical imaging lenses collectively configured: to have the functionality of an f-theta lens. The optical imaging system can be such that a first ratio (k/fm) is between about 0.81 and about 0.88, and a second ratio (fm/fm1) is between about 0.6 and about 0.91, where k is an f-theta scanning coefficient of the optical imaging system, fm is a main scanning focal distance of the optical imaging system, and fm1 is a main scanning focal distance of the first optical imaging lens.

Abstract: A plastic optical element for guiding a scanned light beam in a main scanning direction and a sub-scanning direction, which is prepared by a molding method using a die. The element includes: a main body including at least two optically functional surfaces, which are transfer surfaces formed by contacted with transfer surfaces of the die and through which the light beam passes; and at least two ribs located on surfaces of the main body other than the optically functional surfaces and extending in parallel in the main scanning direction. A recessed portion is present on a surface of at least one of the ribs, and the recessed portion has a side transfer surface and a bottom surface, which is a non-transfer surface, and the distance between the optically functional surfaces is less than the length of the main body in the sub-scanning direction.

Abstract: An optical scanning apparatus having a low-height optical box and accurately arranged reflecting mirrors, and an image forming apparatus using the same. The imaging optical system includes: an imaging optical element which a scanning beam transmits off a profile center thereof in a sub-scanning direction during guiding a beam from a light source to a scanning surface by an imaging optical system via a deflector; a first mirror which deflects the beam transmitted the imaging optical element to fold an optical path toward the edge-surface-A side where within the sub-scanning section, the edge surface A is one of the edge surfaces of the imaging optical element closer to a passing position of the scanning beam; and a second mirror. The second mirror is disposed between the deflection unit and imaging optical element so that the second mirror exists across a plane including the edge surface A.

Abstract: A light scanning device includes a light source emitting light, a polygon mirror reflecting the light while rotating, a mirror member having a mirror surface reflecting the light, reflected by the polygon mirror, toward an object to be scanned, a vibration preventing member attached to a portion of the mirror member excluding the mirror surface to prevent the mirror member from vibrating, and a housing supporting the polygon mirror and the mirror member. The mirror member extends in a predetermined direction in the housing, and the vibration preventing member is divided into a plurality of pieces that are so attached to the mirror member as to adjoin each other in the predetermined direction.

Abstract: An optical scanner includes a light source, an optical element, a deflector, a casing, and a first cover. The deflector deflects the light beam emitted from the light source to scan a photoreceptor through the optical element. The casing includes an upper opening, walls including a transparent plate defining a deflector compartment to accommodate the deflector, and an optical element mounting portion to accommodate the light source and the optical element. The first cover covers the upper opening of the casing and includes a recessed portion recessed toward the bottom of the casing and including a first opening at the bottom thereof facing the deflector. The recessed portion and the walls are directly or indirectly connected to define a single continuous space isolating the deflector compartment from the optical element mounting portion. The recessed portion and the deflector compartment communicate via the first opening.

Abstract: An optical scanning apparatus for scanning a surface to be scanned includes: a light source that emits laser beam; a deflector that deflects the laser beam emitted from the light source; a plurality of optical scanning elements that introduce the deflected laser beam to the surface to be scanned; a housing that holds therein at least one of the light source, the deflector, and the scanning optical elements; a light receiving element that receives the deflected laser beam; a mirror that introduces the deflected laser beam to the light receiving element; and a holder that is provided on the housing and that holds the light receiving element and the mirror integrally.

Abstract: An optical scanner includes an inductor, an electric supply unit, an emitter, a mirror, a first receiving element, a second receiving element, and a measuring unit. The electric supply unit applies a supply voltage to the inductor alternately in opposite applying directions. The mirror reflects a laser beam to scan a photosensitive body within a scanning range. Each of the receiving elements is positioned at one end of the scanning range. The measuring unit measures the scanning time taken for the laser beam to be detected by the second receiving element after the beam is detected by the first receiving element. When the mirror scans the photosensitive body along a first primary scanning line after the mirror scans the body along a second primary scanning line, the electric supply unit varies the supply voltage according to the scanning time measured for the second primary scanning line.

Abstract: A scanning optical device includes a deflector for scanningly deflecting a plurality of light beams from a plurality of light sources, and an imaging optical system for imaging the light beams upon a plurality of scan surfaces to be scanned, wherein at least one piece of reflecting element is provided at each of a plurality of light paths extending from the deflector toward the scan surfaces, wherein there are relations Ra_ave<Rb_ave, and 0.9<?Ra—i/?Rb—i<1.

Abstract: A document management system of the invention is a document management system in which identification information is embedded and an image is printed, and includes a print management unit to generate information relating to printing and including at least information of distribution destinations of printed materials on which the image is printed, an identification information management unit that issues the identification information the number of which is equal to the number of the printed materials, assigns one piece of the identification information to each of the printed materials, correlates the information of the distribution destinations with the identification information, and manages them, and an image formation unit to print, on a recording sheet, the image in which the identification information associated with the information relating to the printing is embedded.

Abstract: At least one of a coupling lens and a cylindrical lens has a diffraction lens surface having a ring-band structure with a height h between adjacent ring-bands. The diffraction lens surface has an area A having a shape similar to that of the ring-band structure with a height h?, where h?h?. The ring-band structure has a function of correcting a fluctuation in focal position of the scanning beam on the scanning surface, and the area A has a function of expanding a focal depth of a light spot on the scanning surface.