Abstract: According to one embodiment, an optical scanning device includes plural light sources, a polygon mirror, a first lens, a first reflection mirror, and a second lens. The polygon mirror deflects lights emitted from the plural light sources in a predetermined direction. The first lens allows the lights emitted from the plural light sources and deflected by the polygon mirror to pass. The first reflection mirror reflects the lights passed through the first lens in a direction different from the deflecting direction of the polygon mirror. The second lens receives incidence of the lights reflected by the first reflection mirror from a direction different from an incident direction of the first lens and allows, with one lens, the lights emitted from the plural light sources to pass.

Abstract: An image forming apparatus includes a scanning optical device which performs scanning on a photosensitive drum with laser light. The scanning optical device includes a polygon motor unit, an emergence unit and a projecting unit. The polygon motor unit includes a polygon mirror which performs the scanning on the photosensitive drum with the laser light emitted from a light source. The laser light emerges from the emergence unit so that the photosensitive drum is irradiated with the laser light. The projecting unit projects to a first side where the photosensitive drum is disposed from a partition wall. The polygon motor unit is disposed in the projecting unit. The emergence unit is disposed on a second side separated from the first side by the partition wall. A gap is provided between the partition wall and the scanning optical device.

Abstract: A deflector deflects a light beam from a light source. A scanning optical system focuses the light beam deflected by the deflector. An image carrying member is located at a focal position of the light beam and includes a surface that is scanned in a main scanning direction with the light beam focused by the scanning optical system. One pixel of an image is formed by a plurality of light spots having different focal positions in at least a sub-scanning direction. At least one light spot from among the light spots is formed on the surface of the image carrying member at a scan timing different from those of rest of the light spots.

Abstract: An optical scanning apparatus has first and second light sources, a deflection scanning device, and first and second scanning optical systems that guide the first and second laser beams deflected for scanning by the deflection scanning device. The first and second scanning optical systems include scanning lenses and a polarization beam splitter arranged in a downstream side of an optical path of the scanning lens, the first scanning optical system including a half-wave plate arranged in the downstream side of the optical path of the scanning lens and in an upstream side of an optical path of the polarization beam splitter, the first laser beam and the second laser beam having different phases by 180 degrees from each other before being incident on the first and second scanning optical systems.

Abstract: An optical scanning apparatus and an image forming apparatus having the optical scanning apparatus includes a before-light-deflecting-unit optical system and a scanning optical system. The optical system includes a first optical device, a second optical device made of a resin material which has an anamorphic negative refracting power in a deflection scanning direction and a deflection scan perpendicular direction and has a larger refracting power in the deflection scan perpendicular direction than a refracting power in the deflection scanning direction, and a third optical device made of a glass material which has substantially no refracting power in the deflection scanning direction and a positive refracting power in the deflection scan perpendicular direction. An interval of the scanning lines formed on the scanned surface is adjusted by displacement of the second and third optical devices in an optical axis direction of the before-light-deflecting-unit optical system.

Abstract: 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: An image forming apparatus includes a correction control unit and a correction amount adjusting unit. The correction control unit performs a phase correction process of changing a drive frequency of a driver for driving and rotating a rotating polygon mirror having a rotational phase difference judged not to coincide by a predetermined correction amount and driving the driver for a period corresponding to a specified clock number by a drive clock signal of the changed drive frequency if a rotational phase difference of another rotating polygon mirror does not coincide with a reference rotational phase difference. The correction amount adjusting unit reduces the predetermined correction amount by a predetermined specified amount and causes the correction control unit to perform the phase correction process again if the rotational phase difference does not coincide with a reference rotational phase difference after the phase correction process is performed.

Abstract: A light sensor generates a detection signal upon receiving laser light. A rotation sensor generates a rotation signal in synchronization with rotation of a polygon motor. A mirror-rotation-signal generating section generates a mirror rotation signal, based on the detection signal. A motor-rotation-signal generating section generates a motor rotation signal, based on the rotation signal. A phase-difference measuring section measures a phase difference between the motor rotation signal and the mirror rotation signal. A prediction-signal generating section generates a prediction signal that is delayed from the motor rotation signal by the phase difference. A switching section switches a control mode between: a mirror control mode in which the mirror rotation signal is used to control a rotational speed of the polygon mirror; and a prediction control mode in which the prediction signal is used to control the rotational speed. A motor driver drives the polygon motor in the selected control mode.

Abstract: Raster Output Scanners and printing systems are presented along with methods for mitigating banding in printing systems, in which electronic banding compensation is employed using cross-process direction light source intensity banding correction profiles tailored to corresponding reflective facets of a rotating polygon.

Abstract: An optical scanner includes a light source including light emitters, an aperture member collimating light beams from the light source, a deflector deflecting the light beams passing through the aperture member, and a scanning optical system condensing the deflected light beams onto a scanned surface to optically scan the surface in a main-scanning direction. The scanning optical system includes a resin scanning system having at least one resin scanning lens. At least one folding mirror/sheet glass is disposed between a scanning lens nearest to the deflector in the resin scanning system and the scanned surface. At least one scanning lens in the resin scanning system has an uneven birefringence distribution with respect to a sub-scanning direction. An optical conjugate image of the aperture member is formed between a lens surface nearest to the deflector in the resin scanning system and a lens surface nearest to the scanned surface with respect to the sub-scanning direction.

Abstract: An image forming apparatus includes: a light source; a photosensitive member; a brushless motor including a stator and a rotor; a rotary polygon mirror rotated by the brushless motor; an energization switching unit that turns on/off energizations of the coils; a voltage detecting unit that outputs a detection signal based on induced voltages generated in coils of the stator by rotation of the rotor; and a motor controlling unit that controls the turning on/off of the energizations by the energization switching unit based on the detection signal. In a non-image forming period after one image forming operation, the motor controlling unit performs a low-speed process where the motor controlling unit maintains a rotation speed of the brushless motor at a speed, which is lower than a speed in the image forming operation, and at which the induced voltages are detectable by the voltage detecting unit.

Abstract: An optical scanning device has a light source comprising a plurality of light emitting points arranged on a plane two-dimensionally; a deflector for deflecting beams emitted from the light emitting points in a main-scanning direction; a first optical system for directing the beams emitted from the light emitting points to the deflector; and a second optical system for directing the beams deflected by the deflector to a photosensitive member and for imaging the beams on a surface of the photosensitive member. The plurality of light emitting points are arranged in a parallelogram lattice composed of M by N lattice points, wherein M and N are integers equal to or greater than six, with none of the light emitting points allocated on central (M?4) by (N?4) lattice points.

Abstract: An optical scanner includes a light source, a scan-deflecting portion including a resonance mirror to scan and deflect along a scan line, a plurality of light receiving sensors for synchronous detection provided on the scan line, a phase controller, an amplitude controller, and an offset controller. The phase controller obtains a difference between a true phase and a target phase, and generates a drive signal incorporating the difference between the true phase and the target phase. The amplitude controller incorporates the difference between a value equivalent of a true amplitude and a value equivalent of a target amplitude into the drive signal generated by the phase controller. The offset controller calculates an offset value by obtaining the difference between each of the time intervals, incorporates the difference between the offset value and a target offset value in the amplitude-controlled drive signal, and supply the drive signal to a driving device.

Abstract: An image forming apparatus includes a light beam output unit configured to output a light beam, a deflection unit for deflection scanning in a main scanning direction of a photosensitive member by reflecting the light beam from the light beam output unit, a timing information detection unit configured to detect timing information of the deflection scanning by the deflection unit, a calculation unit configured to calculate a correction amount of the main scanning direction for a next scan based on the timing information, a light beam modulation control unit configured to generate a light beam modulation signal based on image data and the correction amount, and a drive unit configured to drive the light beam output unit based on the light beam modulation signal.

Abstract: A pixel clock generator includes a frequency divider 4 that generates a pixel clock PCLK based on a high frequency clock VCLK, a comparator 5 that calculates an error Lerr in the time obtained by integrating a cycle of the pixel clock PCLK for a target number RefN from a time when synchronization signals SPSYNC and EPSYNC are detected, a filter 6, and a frequency calculating unit 7 that sets a frequency dividing value M of the frequency divider 4. The filter 6 and the frequency calculating unit 7 calculate an average of a frequency of the pixel clock PCLK based on the error Lerr, determine a reference error value from the error Lerr in N-cycles, calculate offset values of the frequencies of N pieces of pixel clocks PCLK based on a difference between the reference error value and the error Lerr, and calculate the frequency dividing value M based on a result obtained by adding the circularly selected offset values and the average of the frequency of the pixel clock PCLK.

Abstract: A light scanning apparatus including: a light source to emit a laser beam; a light source driving unit to turn on and off the light source according to image data and a pixel clock; a rotary polygon mirror to deflect the light beam; a motor to rotationally drive the rotary polygon mirror; and a control unit to control a rotary speed of the motor to generate an acceleration control signal for accelerating the rotary speed and a deceleration control signal for decelerating the rotary speed, wherein for the acceleration control signal, the driving unit corrects the frequency of the pixel clock to be higher than the frequency, which is before the acceleration control, and for the deceleration control signal, the driving unit corrects the frequency of the pixel clock to be lower than the frequency, which is before the deceleration control.

Abstract: A pre-deflector optical system includes an isolator arranged on an optical path of a light beam from a light source. The isolator has a first surface with different light transmittances depending on a polarization state of an incident light beam on a first side close to the light source and a second surface imparting an optical phase difference of a ¼ wavelength to the incident light beam on a second side. A deflector deflects the light beam passed through the pre-deflector optical system. A rotation mechanism rotates the isolator around its optical axis. A holding member holds the light source and the isolator in a predetermined positional relationship.

Abstract: An optical scanning apparatus includes a light source, a rotating polygonal mirror, a scanning optical system, a detector, and a light emission controller. The light source includes plural light emitting elements. The rotating polygonal mirror is irradiated with light beams. While rotating, the rotating polygonal mirror reflects and deflects, in a deflecting direction, light beams emitted from light emitting elements in a first direction to propagate through one point in the deflecting direction substantially at the same time. The scanning optical system causes the reflected and deflected light beams to scan over an object. The detector detects the timing at which a light beam propagates through a detection point. When the light beams propagate through the detection point, the light emission controller causes light emitting elements in a row in the first direction other than light emitting elements at both ends of a projection plane to emit light.

Abstract: An optical scanning device is configured in such a manner that, of four light beams for colors corresponding to cyan, magenta, yellow, and black, the number of folding mirrors disposed in the optical path of a light beam corresponding to an mage in yellow having the highest brightness and the lowest visibility is the greatest number, and further, the number of the folding mirrors disposed in the optical path of a light beam corresponding to an image in black having the lowest brightness and the highest visibility is the least number. It is thus possible to reduce unevenness in color in the color image resulting from the folding of light beams by the folding mirrors.

Abstract: An optical device includes an optical component that reflects or shapes a light beam. In a particular embodiment, the optical device can include a bending moment generating structure that generates a bending moment in a supported portion of the optical component. The optical device can also include an adjusting mechanism that adjusts the bowing amount of the optical component by adjusting the bending moment of the bending moment generating structure.

Abstract: An optical scanning device includes four light sources, a pre-deflector optical system, a polygon mirror, an optical scanning system, etc. The optical scanning system includes deflector-side scanning lenses made of glass, imaging-surface-side scanning lenses made of resin, polarized light splitters, and reflecting mirrors. The deflector-side scanning lenses, the imaging-surface-side scanning lenses, the polarized light splitters, and the reflecting mirrors are arranged in this order on an optical path of light going from the polygon mirror toward drum-shaped photosensitive elements.

Abstract: A two-dimensional light scanning apparatus includes: a deflector to drive at a resonance frequency in a main scanning direction and a sub-scanning direction different from the main scanning direction; a position sensor to detect a scanning position of the deflector; a resonance frequency predicting part to predict the resonance frequency of the deflector; and a deflector drive control part to: for drawing a Lissajous figure in which scanning trajectories of the deflector do not overlap with each other for one frame, store a plurality of pairs of respective frequency ratios of driving signals in the sub-scanning direction to driving signals in the main scanning direction, and respective phases of the driving signals in the sub-scanning direction with respect to the driving signals in the main scanning direction; select one pair of a frequency ratio and a phase; and control the deflector with a driving signal.

Abstract: The reading apparatus is provided with: an optical image forming unit that forms an optical image on a recording medium by irradiating, with light, the recording medium on which an image is formed and which is transported in a slow scan direction; a reading unit that reads a position in a fast scan direction of the image formed on the recording medium transported in the slow scan direction and a position in a fast scan direction of the optical image, by using a minification optical system; and a registration correction unit that corrects a registration error in the fast scan direction of the image read by the reading unit, by using the position in the fast scan direction of the optical image read by the reading unit.

Abstract: An scanning optical apparatus of present invention converts plural light beams emitted from corresponding light source units by a light beam conversion unit, deflectively scans by a deflection unit, focuses by an imaging optical unit onto corresponding scanned surfaces. At least two of light source units are arranged along a direction perpendicular to the direction in which the light beams are emitted. The light beam conversion unit includes plural light beam conversion elements that reflect the light beams emitted in the same direction from the light source units to deflect the light beams in the same direction. Each of the light beam conversion elements has at least one reflecting surface having a power and at least one diffracting surface having a power, and has different powers with respect to the main scanning direction and with respect to the sub scanning direction.

Abstract: An optical scanning unit may include a light source unit configured to emit a light beam, an optical housing configured to receive and support the light source unit, an optical device configured to deflect the light beam and to focus the light beam on a light receiving member, and a fixing member configured to fix the light source unit to the optical housing by applying pressure to the light source unit, wherein the pressure is applied in a direction, which is substantially perpendicular to an optical axis direction of the light source unit.

Abstract: An image forming apparatus including a black developer with increased capacity. The image forming apparatus includes optical scanners, where the optical scanners have the same focusing distance from the light source to the photo conductor, and the light reflecting unit of one of the optical scanners is arranged at a position different from the light reflecting unit of another optical scanner, such that intervals between the developers vary. Accordingly, although developers of the same type are used, the capacity of the black developer, which is most frequently used, may be easily increased by arranging the relative positions of the developers.

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: Provided is a planar lighting apparatus performing a display (i) without luminance nonuniformity, (ii) with a specified luminance distribution in a scanning direction and (iii) having a high luminance and a large area. Also provided is a liquid crystal display device using the planar lighting apparatus. In the plan lighting apparatus, a scanning light quantity of a scanning light 13 to a light guide section 15 is controlled by a controller 20, so at to emit an outgoing light 16 from a principal surface 17 with a specified luminance distribution in a scanning direction 21 of the scanning light 13.

Abstract: An optical scanning device includes a first optical a light source that has a plurality of luminous points; a first optical system that shapes a plurality of beams of light; a rotary polygon mirror an optical scanning system that causes the beams of light deflected to form images on a surface to be scanned, wherein ? is assumed to be half of an angle formed between the optical axis of the first optical system and the optical axis of the optical scanning system within the deflecting/scanning surface, ? is assumed to be a distance between an intersection dc and an intersection hh, wherein ? is set to be zero or a negative value, given that ? is defined positive when the intersection dc is present on the optical-scanning side of the intersection hh.

Abstract: An image forming apparatus includes a light source, a polygon mirror, and a plurality of photosensitive elements. The polygon mirror has a plurality of reflection surfaces that reflect a light beam at different angles. The light beams deflected by the reflection surfaces travel along different optical paths and impinge on different photosensitive elements. A light-beam control unit controls emission of the light beam from the light source depending on a distance between the deflecting unit and the photosensitive elements thereby performing an f? correction of the light beam.

Abstract: A disclosed optical scanner includes a light source unit and a control unit configured to control the light source unit. Light emitted from the light source unit is scanned to expose a scan object surface and form an image on the scan object surface. The light source unit includes plural light sources arranged at a density equal to N (N being an integer of two or more) times higher than a density of pixels on the scan object surface. The control unit controls the light source unit such that one pixel is formed by at least two of the light sources.

Abstract: Provided is an optical scanning apparatus has a plurality of light emitting portions and an incident optical system including optical element, wherein each shape of optical surfaces in a main scanning section of optical elements is formed into a noncircular shape. When defining that W is a space between specific light emitting portions farthest from an optical axis in the main scanning direction, La is an optical path length between an aperture stop and a specific optical surface closest to the light source unit among the noncircular optical surfaces of the incident optical system, f1 is a focal length of the incident optical system in the main scanning direction, and D is a light flux width in the main scanning direction of a light flux emitted from the specific light emitting portion in the main scanning direction on specific the optical surface, the equation 2D?|W·La/2f1|?D/8 is satisfied.

Abstract: A MEMS device, a printer and a method of printing is presented including providing a light source producing a modulated beam of light, positioning a mirror with a reflective surface to intercept the modulated beam of light. Allowing the mirror to rotate on a single-axis hinge structure such that the resultant reflected beam is swept in a scan plane and creating an image at an intersection of the scan plane and an image plane. Causing the mirror to rotate about the single-axis hinge structure and to oscillate at a tilt about the single-axis hinge structure, wherein the resultant reflected beam of light forms a lemniscate pattern along the image plane, and wherein the lemniscate pattern has an inner angle between a left sweep segment and a right sweep segment of the image.

Abstract: Systems and methods for reducing the degradation of image quality due to banding in an image processing system by detection of both integrated intensity and peak intensity of a laser beam reflected from the polygon mirror facet(s) of a motor polygon assembly. A banding detector is adapted to enable measurement of peak intensity and integrated intensity of the laser beam(s) reflected from the polygon mirror facet(s). Polygon facet induced banding can be determined from the measurements and can be used for sorting/manufacturing raster output scanners and/or compensating for the induced banding.

Abstract: Methods and apparatus include improving print quality of a bi-directionally scanning electrophotographic (EP) device, such as a laser printer or copy machine, according to ambient pressure in which operated. A moving galvanometer or oscillator reflects a laser beam to create scan lines of a latent image in opposite directions. A damping of the motion occurs per air density implicated by temperature and pressure, where the pressure changes occurring especially from altitude changes. During use, a drive signal, such as a pulse train, moves the galvanometer or oscillator at or near its resonant frequency. Based on a parameter of the drive signal, such as pulse width, the ambient pressure can be made known. In general, a high-pressure environment requires a relatively longer pulse width to resonate the galvanometer or oscillator in comparison to a shorter pulse width for a low-pressure environment. Corrections to print quality stem from the determined ambient pressure.

Abstract: An exposure unit which exposes photoconductive drums having rotary axes thereof arranged parallel to each other on a single plane by light beams, includes one or more polygon mirrors each having a plurality of reflection surfaces, where the one or more polygon mirrors rotate about a common rotary axis. Each light beam is deflected by the one or more polygon mirrors and scans the surface of a corresponding photoconductive drum. The common rotary axis is separated from the rotary axes of the photoconductive drums by identical distances along respective normals which are perpendicular to both the common rotary axis and the rotary axes of the photoconductive drums.

Abstract: A semiconductor integrated circuit device controlling a first light amount of light emitted from a light source based on a second light amount of light entering a light amount detection part so that the first light amount becomes a target level is disclosed. The semiconductor integrated circuit device includes a comparison part configured to compare a voltage corresponding to the second light amount and a reference voltage corresponding to the target level; and a drive current control part configured to control a drive current supplied to the light source based on the result of the comparison by the comparison part. The drive current control part includes a return light identification part configured to determine whether the second light amount includes a third light amount of return light occurring discontinuously.

Abstract: An optical scanning device includes an input optical system having an input optical element, for projecting a light beam from a light source device onto a deflecting surface of an optical deflector, and an imaging optical system having an imaging optical element, for imaging the light beam scanningly deflected by the deflecting surface of the optical deflector, on a surface to be scanned, wherein the light beam is obliquely incident on the deflecting surface in a sub-scan section, wherein the imaging optical element has at least one optical surface which is decentered in the sub-scan section, wherein the input optical element has at least one optical surface having an asymmetric and aspherical surface shape, wherein the input optical element has a thickness dm1 in the sub-scan section and at a position where a first marginal light ray of the light beam passing through the input optical system, which first marginal light ray is closer to an optical reference axis than the principal ray of that light beam is, p

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 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: An optical beam scanning device includes a polygon mirror 80 in which tilt angles with respect to a rotation axis of the polygon mirror 80 of respective plural reflecting surfaces are set to angles corresponding to photoconductive members associated with the respective reflecting surfaces, a post-deflection optical system A1 that guides light beams reflected and deflected by the respective plural reflecting surfaces in the polygon mirror 80 to the photoconductive surfaces of the photoconductive members corresponding to the respective reflecting surfaces, and a pre-deflection optical system 7a that shapes the light from the light source to be a light beam of a predetermined sectional shape and guides the light beam to the polygon mirror 80, the pre-deflection optical system 7a guiding the light from the light source to the polygon mirror 80 through an optical path that passes, in the main scanning direction, on an optical axis of the post-deflection optical system A1 and passes, in the sub-scanning direction,

Abstract: The apparatus is adapted to deflect a light beam from a laser light source for each of the color components by means of a deflection mirror surface which oscillates, thereby making the light beam reciprocally scan in a main scanning direction. In this apparatus, however, only a light beam SL which scans in a first direction (+X) of the main scanning direction is irradiated in an effective image region on a photosensitive member, so as to form a latent image thereon. The resultant latent image is developed to form a toner image. Since image formation is performed using only the light beam SL which scans in the first direction (+X), the images may be formed at the consistent density irrespective of the image types. Furthermore, the scanning directions of the light beams SL for all the color components are uniformly defined to be the first direction (+X), so that the toner images of the respective colors may maintain the consistent density.

Abstract: In an optical scanning device, when pixel density is taken to be n, number of the light beams is taken to be b, and number of the deflection surfaces of a deflecting unit is taken to be p, a spatial frequency S denoted by S=1/(1/(25.4/n×b×p) is within a range of a spatial frequency characteristic for a visual perception system of a high relative luminous efficiency. When spacing between ends in a sub-scanning direction of a scanning line formed by one scan by the deflection unit is taken to be L1, and spacing between all progressive scanning lines at the surface to be scanned is taken to be L2, then L1>(k?1)×L2 is satisfied, where k is a total number of light emitting points of a light source.

Abstract: An optical scanning device deflects a light beam emitted from a light source device by a vibrating mirror, scans a scanning surface with deflected light beam, and focuses the light beam onto the scanning surface by a scanning imaging optical system. The optical scanning device includes an offset detecting unit that detects an offset that is a deviation between a center of vibration amplitude of the vibrating mirror and a center of an optical scanning area and an adjusting unit that adjusts the center of the vibration amplitude when the offset detected by the offset detecting unit is larger than a predetermined value.

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: A light source device includes a light source, a coupling lens, a first opening plate, a second opening plate, a photoreceptor, a package member, a cover glass, a half mirror, and a light source control device. In relation to a main-scanning corresponding direction and a sub-scanning corresponding direction, divergence angles ?m and ?s of a light beam output from the light source, emission angles ?m1 and ?s1 of a light beam passing through an opening portion A, and emission angles ?m2 and ?s2 of a light beam passing through an opening portion B satisfy relationships |(?m1??m2)/?m|?0.085 and |(?s1??s2)/?s|?0.085.

Abstract: An optical beam scanning apparatus according to the present invention includes a light source, a pre-deflection optical system, a light deflecting device, a post-deflection optical system configured to at least include one or plural first optical elements which act on the luminous fluxes for all color components, plural second optical elements which respectively act on the luminous fluxes for each of color components, and plural first reflection mirrors that are respectively provided on an upstream side of the plural second optical elements in optical paths and reflect luminous fluxes emitted from the first optical elements, and a position adjusting mechanism configured to adjust positions of the first reflection mirrors.

Abstract: An optical deflector of the present invention includes a movable mirror and torsion bars supporting the mirror and formed integrally with the mirror. The mirror reciprocatingly vibrates to reflect a light beam to thereby deflect it. The mirror is curved in the form of an arch in a section including at least the torsion bars. The mirror deforms little during vibration even if it is thin. Small power can cause such a thin mirror to vibrate with a large amplitude.

Abstract: A compact light scanning apparatus is disclosed which can provide a high light scanning efficiency. The apparatus includes a scanner that scans a light beam from a light source to form an image in an effective scan area, and a light detector that detects light. The light scanning apparatus includes a light-introducing member that introduces a partial light beam component of the light beam within its light beam width to the light detector in a state in which the light beam scanned by the scanner proceeds toward outside the effective scan area.

Abstract: A CPU (91) of an image forming apparatus includes a beam detecting part (911) that detects each of laser beams scanning by a predetermined number (e.g., four) of polygon mirrors (332) at a preset position (where a beam sensor (335) is disposed), a reference phase setting part (912) that sets a reference phase that is a phase to be a reference of the predetermined number of rotation phases of the polygon mirrors (332) based on a result of detection by the beam detecting part (911), and a phase control part (913) that controls polygon motor (330) so that predetermined number of rotation phases of the polygon mirrors (332) match the reference phase.