Abstract: In a light-source driving device, a high-frequency clock generating circuit generates two high-frequency clock signals having mutually different phases, an image-data creating circuit creates a plurality of image data corresponding to a plurality of light-emitting units according to image information, and a write control circuit creates a plurality of modulated data corresponding to the light-emitting units from the plurality of image data and separately controls output timings of the plurality of modulated data by using a time, as a unit, corresponding to a phase difference between the two high-frequency clock signals. The write control circuit includes two data switching circuits that set a correspondence relation between image data and PWM data based on one of a relation between an array of the light-emitting units and an array of a plurality of light spots and a relation between a surface to be scanned and a main scanning direction.

Abstract: In an image forming apparatus according to the invention, an optical beam scanning apparatus of an overillumination scanning optical system includes a laser, a pre-deflection optical system, a polygon mirror, and a post-deflection optical system, wherein the post-deflection optical system includes at least one optical element configured by allowing a resin to flow into a molding die through a gate opening provided in advance to the molding die and then molding the resin into a prescribed shape; and in the optical element, a side corresponding to aside of the gate opening through which the resin flows is provided to a light incidence side where the luminous flux enters into the polygon mirror.

Abstract: A variable view imaging system for observation of micro object with variable view orientation and position includes a telecentric lens group, a scanning mirror, wedge prisms, a deformable mirror and related optical elements. The combination of a scanning mirror and a telecentric lens group decouples the motion of scanning mirror and the view angle. The view angle is determined only by the angle of the wedge prisms. This design increases the zenith angle of the view and simplifies the kinematics of the system. The wedge prisms and the scanning mirror can supply a flexible view in a compact way. The wavefront error induced by the wedge prisms is corrected by the deformable mirror. In order to achieve the desired view state during operation, the scanning mirror angle and the wedge prisms angle are calculated iteratively based on the kinematics and Jacobian matrix of system.

Abstract: A light scanning unit and an image forming apparatus having the same. The light scanning unit to form an electrostatic latent image corresponding to image information on a photosensitive body may include a light source, a deflector to deflect light generated from the light source in a main scanning direction, an imaging lens to focus deflected light to the photosensitive body, and at least a reflection mirror to change a traveling direction of light. A deviation of light quantity generated in a main scanning direction by a light quantity ratio generated by internal absorption of the imaging lens and a light quantity ratio generated by a polarization state of light may be compensated for by the reflection mirror.

Abstract: An image forming apparatus provided with an optical beam scanning apparatus according to the invention includes a semiconductor laser device, a pre-deflection optical system, a polygon mirror, and a post-deflection optical system, wherein at least one imaging lens for imaging the luminous flux is provided in the post-deflection optical system includes; at least one projection on a vertical surface to a sub-scanning direction axis is provided in the imaging lens; and at least one positioning member having an engaging groove into which the projection is interfitted and which is engaged in a concave-convex shape is provided in the housing unit of the optical beam scanning apparatus. In accordance with an image forming apparatus according to the invention, in a scanning optical system using an imaging lens or an imaging mirror, influences against optical characteristics following an environmental fluctuation or a change with time can be reduced.

Abstract: An optical device is disclosed in which inner space is kept clean so as to reduce the adhesion and adsorption of pollutants to the surface of the optical device, thereby preventing the degradation of the optical device and accurately maintaining the alignment of the coupling between the laser light from a semiconductor laser and the incident end surface of an optical fiber. The optical device includes a lens system unit condensing the laser light emitted from the semiconductor laser and guiding the laser light onto an incident end of the optical fiber; a variable volume mechanism unit defining an hermetically enclosed space; and an adsorbent unit disposed in the hermetically enclosed space, in which either the incident end of the optical fiber or the lens system unit or both are in contact with the hermetically enclosed space containing the adsorbent unit.

Abstract: A multibeam optical scanning device includes a plurality of light sources; a collimating lens; an aperture; a cylinder lens; a light deflecting unit; a scanning optical system; and a phase adjusting element. The phase adjusting element performs phase adjustments of wavefronts of the light beams to expand a depth allowance without substantially increasing a beam spot size of each of the beam spots on the scanning surface.

Abstract: An optical scanning apparatus includes a plate member, having a rotation axis and a reflection surface, that deflects and scans a laser beam emitted from a light source by performing reciprocating-rotation around the rotation axis, an actuator configured to drive the plate member, an f?-lens configured to focus the laser beam deflected by the plate member on a surface of a photosensitive drum, and an optical box configured to house the plate member, the actuator, and the f?-lens. The actuator is provided nearer to a side of the optical box toward which the laser beam is reflected by the reflection surface than the reflection surface of the plate member is.

Abstract: A light scanning device includes: a light source; an aperture stop regulating a width of a light beam emitted from the light source; a deflector deflecting and scanning the light beam emitted from the light source; at least one scanning lens forming an image on a scanned surface with the light beam deflected and scanned; and a phase-type optical element. In the light scanning device, a phase modulation portion is provided to at least a portion of the phase-type optical element, and a phase difference between the phase modulation portion and a region other than the phase modulation portion is not ? [radian]. Thus, asymmetry in a curve representing the relationship between a beam spot diameter and defocus can be corrected to reduce variation of the beam spot diameter with respect to the defocus. Consequently, highly-accurate light scanning can be performed.

Abstract: An image forming apparatus provided with an optical beam scanning apparatus according to the invention includes a semiconductor laser device, a pre-deflection optical system, a polygon mirror, and a post-deflection optical system, wherein at least one imaging lens for imaging the luminous flux is provided in the post-deflection optical system includes; at least one projection on a vertical surface to a sub-scanning direction axis is provided in the imaging lens; and at least one positioning member having an engaging groove into which the projection is interfitted and which is engaged in a concave-convex shape is provided in the housing unit of the optical beam scanning apparatus. In accordance with an image forming apparatus according to the invention, in a scanning optical system using an imaging lens or an imaging mirror, influences against optical characteristics following an environmental fluctuation or a change with time can be reduced.

Abstract: Provided are a light scanning unit capable of compensating for a zigzag error, an imaging apparatus having the same, and a method of compensating for a zigzag error of the light scanning unit. The light scanning unit may scan light beams using an oscillation mirror configured to rotatably oscillate. The light scanning unit may deflect light beams in a sub-scan direction in synchronization with the rotatable oscillation of the oscillation mirror, thereby compensating for a zigzag error caused by reciprocative scanning of the oscillation mirror.

Abstract: An optical scanning device capable of stably and uniformly performing linear optical scanning by using a high-brightness light source is provided. The device includes: at least one laser light source (11) for emitting a laser light; a deflection section (15) for deflecting and scanning the laser light emitted from the at least one laser light source (11); and a light guide plate (17) of which a side surface is irradiated with the laser light deflected and scanned by the deflection section (15). The at least one laser light source (11) includes a multi-mode fiber light source, or a broad-stripe semiconductor laser light source arranged such that a vertical direction of a stripe structure is parallel to a scanning direction. An exit pupil in a thickness direction, which is perpendicular to the scanning direction, is formed at least in one area on the side surface of the light guide plate (17).

Abstract: A display apparatus that displays an image on a retina of a user, the display apparatus comprising: an image output unit (100) which includes a light source (101, 110), a wavefront shape change unit (102, 109), and a scan unit (103, 108) and is configured to output display light for displaying the image; and a deflection unit (104, 107) configured to deflect, toward an eye of the user, the display light outputted by the image output unit (100). The deflection unit (104, 107) has a deflection characteristic of suppressing image distortion caused by a change in relative position of the deflection unit (104, 107) with respect to a pupil of the user.

Abstract: Apparatus for generating optical radiation includes a laser, which is configured to operate in multiple transverse modes simultaneously so as to generate an input beam, which is characterized by a first speckle contrast. The transverse modes of the input beam are optically mixed so as to generate an output beam have a second speckle contrast, which is substantially less than the first speckle contrast.

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: A diffractive-optical element that is transparent includes a diffraction surface that is formed by a step. A width of the step is set substantially equal to a common multiple of ?i/{n(?i)?1} for two or more wavelengths, where ?i (i=1, 2, . . . ) is a wavelength and n(?i) is a refractive index with respect to the wavelength ?i.

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: The present invention relates to a projection device comprising a body (1) with a projection opening (2) for light projection. The body (1) encloses at least a light source (7), a scanning unit (8) and a deflection unit (3). The deflection unit (3) is mounted movable between an extended position and a non extended position. The scanning unit (8) is arranged and designed to scan a deflection area of the deflection unit (3) in the extended position with a light beam emitted by the light source (7). In the extended position part of the deflection unit (3) extends through the projection opening (2) to prevent a human eye to come too close to the projection opening (2). In the extended position the deflection unit (3) deflects the light beam from the scanning unit (8) towards a projection area. In the non extended position the deflection unit (3) does not deflect the light beam from the scanning unit (8) through the projection opening (2).

Abstract: For deflecting a laser beam (200) with a deflection mirror (21) arranged displaceably about a rotation axis (c), a beam-shaping optical element (22) is disposed upstream of the deflection mirror (21), said optical element being designed to project the laser beam (200) onto the deflection mirror (21) with a beam width that is reduced in the direction of the rotation axis (c). The deflection mirror (21) has a mirror width which is oriented in the direction of the rotation axis (c) and which is narrower than an unreduced input beam width of the laser beam (200) upstream of the beam-shaping optical element (22). Moreover, a beam-shaping optical element (23) is disposed downstream of the deflection mirror (21), said optical element forwarding the laser beam (202) from the deflection mirror (21) with a beam width corresponding to the unreduced input beam width.

Abstract: The optical scanning device scans an object with plural laser beams, and includes a light source, which emits plural parallel laser beams in a predetermined direction and which has a stem portion having a first notch; and a support having an opening, with which the light source is engaged so as to be rotatable on an axis parallel to the plural light beams, and a second notch located on a part of the opening so as to overlap with the first notch when the light source is engaged with the opening. By inserting a slotted screwdriver, etc., into the space formed by the two notches and rotating the screwdriver, the angle of the light source can be adjusted and thereby the pitches of the laser beams can be adjusted.

Abstract: An optical pattern uses a single rotating component. The rotating component includes a number of deflection sectors. Each sector deflects an incident optical beam by a substantially constant angular amount although this amount may vary from one sector to the next. The rotating component may be combined with an imaging lens group that produces, for example, image points, spots, or lines displaced along a line locus.

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, a first sensor configured to detect a part of the luminous fluxes deflected by the light deflecting device, one or plural first optical elements configured to be provided in the post-deflection optical system and act on the luminous fluxes deflected by all the deflection surfaces of the light deflecting device; and a second optical element having positive power in the sub-scanning direction configured to be provided in an optical path between any one of the first optical elements and the first sensor and act on the luminous fluxes deflected by all the deflection surfaces of the light deflecting device.

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: 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 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 forward-looking, optical coherence tomography, endoscopic probe is disclosed capable of high resolution with a small diameter. Light is focused and scanned during three passes through a lens. A light source supplies light to the proximal side of the lens. The light makes a first pass through the lens, and is reflected from a fixed mirror on the distal side. The reflected light makes a second pass from the distal side to the proximal side, and exits the lens at the proximal side, and is reflected by a scanning mirror. The light makes a third pass through the lens from the proximal side to the distal side to a sample to be imaged. The light is focused during each of the three passes through the lens. Light reflected from the sample passes back through and is focused by the same system.

Abstract: Method and apparatus for optical scanning includes a sliding bed and a center adjusting unit. The sliding bed predetermines a position of an optical element in a light axis direction. The optical element has at least one lens surface to be have been subjected to a precision-figure transferring and optically scanning at least one light beam generated by a plurality of light sources and deflected by a rotary mirror. The center adjusting unit moves the optical element to make a lateral center of a curvature radius of the optical element exactly on a light axis center. This paper also describes an optical element itself, a method and apparatus for positioning and fixing the optical element. This paper further describes a molding tool for making the optical element.

Abstract: A technique is provided which enables proper correction of optical characteristics in accordance with change in ambient temperature. An optical beam scanning device capable of causing a luminous flux from a light source to scan a photoconductive surface of each of plural photoconductors in a main scanning direction, includes: a polygon mirror 80 which reflects and deflects an incident luminous flux by plural reflection surfaces arrayed in a direction of rotation, and thereby causes the incident luminous flux to scan in the main scanning direction; and a post-deflection optical system A which includes plural optical devices and which guides the luminous flux reflected and deflected by each of the plural reflection surfaces in the polygon mirror 80, to a photoconductive surface of a photoconductor to which the luminous flux should be guided.

Abstract: An optical element includes a light transmission member 100 having an incident plane 5 on which a light beam is incident and an output plane 7 from which the light beam that was previously incident on the incident plane 5 is output, and an oscillation member 101 adapted to oscillate the light transmission member 100. The light transmission member 100 is a polygonal prism having the incident plane 5 and the output plane 7 that are arranged such that the plane that includes the incident plane intersects the plane that includes the output plane. The oscillation member 101 oscillates the light transmission member in a direction in which the propagation length for which the light beam being previously incident on the light transmission member 100 travels through the light transmission member 100 changes. Accordingly, it is possible to provide an optical element for displaying images with reduced speckled noise in cases in which light sources emit coherent light beams.

Abstract: An optical scanning device includes an oscillating mirror portion having a reflection surface, and a frame portion holding the oscillating mirror portion. The optical scanning device reflects an incident optical flux by the reflection surface so as to convert the incident optical flux into a scanned optical flux. The optical scanning device further includes a reflection portion having a first reflection surface and a second reflection surface which are arranged in substantially V-shaped inclined surfaces. The first reflection surface reflects the incident optical flux and radiates the reflected light toward the oscillating mirror portion. The second reflection surface receives the reflected light from the oscillating mirror portion and radiates the reflected light as the scanned optical flux.

Abstract: An optical pattern uses a single rotating component. The rotating component includes a number of deflection sectors. Each sector deflects an incident optical beam by a substantially constant angular amount although this amount may vary from one sector to the next. The rotating component may be combined with an imaging lens group that produces, for example, image points, spots, or lines displaced along a line locus.

Abstract: An optical scanning apparatus allowing reduction in the size of the overall apparatus and the size of an imaging optical system LB with the use of an optical deflector that swings back-and-forth and an image forming apparatus using such an optical scanning apparatus, comprising: light source means; a condense optical system that condenses a light beam emitted from the light source means; an optical deflector that deflects the light beam emergent from the condense optical system; and an imaging optical system that images the light beam deflected by a deflection surface of the optical deflector on a scanning surface, wherein the optical deflector has a function of moving the deflection surface back-and-forth, the light beam emergent from the condense optical system converges in a sub-scanning cross section, and the convergence position is on the light source side of the deflection surface.

Abstract: An optical scanning device includes: a light source; a first optical element that converts light emitted from the light source to parallel light; a deflection element that deflects the light in a fast scanning direction to scan a surface of an object to be scanned with the light at a constant speed; a second optical element that guides the light to the deflection element; and a third optical element that focuses the light deflected by the deflection element onto the surface of the object to be scanned, at least one surface among surfaces of the third optical element that intersect the light including a surface form which affects only one of fast scanning direction characteristics or slow scanning direction characteristics at an image plane.

Abstract: An optical element holder is provided with a holding frame having a side surface provided spaced apart by a specific distance from an end portion of the correction lens in a longitudinal direction by deeming a light scanning direction as the longitudinal direction and holding the correction lens so as to cover the correction lens except for at least an incident portion and an exiting portion of light, and a pushing member that pushes the correction lens toward the holding frame, so that displacement in the light scanning direction due to heat of the optical element is lessened.

Abstract: A system and method are used to pattern light using an illumination system, an array of individually controllable components, and a projection system. The illumination system supplies a beam of radiation. The array of individually controllable elements patterns the beam. The array of individually controllable elements comprises mirrors having first and second steps on opposite edges. The projection system projects the patterned beam onto a target portion of an object. In various examples, the object can be a display, a semiconductor substrate or wafer, a flat panel display glass substrate, or the like, as is discussed in more detail below.

Abstract: An optical scanning apparatus includes a light source, a light source driving unit that turns on the light source according to image information, a deflector that deflects and scans a light beam emitted from the light source according to sinusoidal vibration, and a scanning/imaging optical system that guides the light beam from the deflector to a scanned surface. The scanning/imaging optical system satisfies two conditions, i.e., (1) provided that the deflector moves in such a manner that an angular velocity is constant, linearity is made larger at a most peripheral image height than at a central image height within a range of an effective writing width, and (2) when a deflection angle of the deflector has a sinusoidal characteristic, the linearity is made smaller at the most peripheral image height than at the central image height within the range of the effective writing width.

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: A light source provided with a laser element that emits a laser beam emits a laser beam for synchronization control. A synchronization mirror reflects the laser beam so as to allow a light receiving element in the light source to detect the laser beam. The synchronization mirror is provided on f-? lenses opposite to a light deflector, such that the f-? lenses are provided neither on a light beam path that connects the light source and the light deflector nor on a light beam path for synchronization control that connects the light deflector and the synchronization mirror.

Abstract: An optical pattern generator includes one or more multi-faceted rotating optical elements that introduce an offset that is rotation insensitive. The component that generates the offset is rotationally symmetric around the rotational axis of the optical element. Thus, as the optical element rotates, the effect of the offset component does not change. In addition, rotating optical elements may be designed to counteract unwanted optical effects of each other.

Abstract: A surface-emitting laser element for emitting light in a direction perpendicular to a substrate, including a substrate with a normal direction of a principal plane inclining toward one direction of <111> with respect to one direction of <100> and a mesa structure formed on the substrate and having a narrowed structure with an oxide produced by oxidizing a part of a layer to be oxidized selectively, containing aluminum and surrounding an electric current passage area, wherein a cross-section of mesa structure being parallel to the substrate is parallel to a substrate surface and orthogonal to both one direction of <100> and one direction of <111> and a length in a first direction passing through a center of the electric current passage area is more than a length in a second direction parallel to a substrate surface and orthogonal to the first direction.

Abstract: A scanning optical system includes a deflector for deflecting a laser light flux from a light source and a second imaging optical system for focusing the laser light flux deflected by the deflector on a target scanning surface. The second imaging optical system has at least one optical function surface on which an optical function portion including a plurality of convex portions arranged therein so as to have a serrate cross section is formed in at least part thereof. The optical function surface is formed so that a width of each of the convex portions in an arrangement direction in which the convex portions are arranged is larger than a width of the laser light flux in the arrangement direction, which enters the optical function surface.

Abstract: An aperture has an aperture opening that transmits a predetermined portion of a light beam. A phase optical element changes a phase of a portion of a light beam. A scanning lens focuses the light beam into a beam spot on a scanning surface. The phase optical element has a function of increasing light intensity of a side-lobe of the scanning beam near the scanning surface. The aperture opening is set to satisfy 0.03?(SR?SA)/SR?0.20, where SR and SA are areas of a rectangle circumscribing the aperture opening and the aperture opening, respectively. The function of the phase optical element and the aperture expand a depth allowance of the beam spot.

Abstract: An optical scanning device includes a laser light source that emits a laser beam; a light deflector that deflects the laser beam; a scan-imaging optical system that focuses the laser beam deflected from the light deflector on a scanning surface to optically scan the scanning surface; a diffractive optical element receives the laser beam and diffracts a portion of the laser beam as a diffracted light; and a detecting unit that detects the diffracted light. The laser light source is a surface-emitting laser light source. Moreover, the diffractive optical element is made of plastic material having a linear expansion coefficient within a temperature variation range of the optical scanning device nearly equal to a rate of wavelength change of an emission wavelength of the laser light source within the temperature variation range.

Abstract: The present invention provides an image display apparatus including a spatial light modulating element formed with a plurality of light modulating elements for each modulating light from a light source and arranged in a row or a plurality of rows, a projection optical system for forming a first image on a basis of the light modulated by the spatial light modulating element, light deflecting means for forming a second image by reflecting the first image formed by the projection optical system so as to scan the first image in a direction orthogonal to a longitudinal direction of the first image, which is a longer direction of the first image, a magnifying and projecting system for magnifying the second image and projecting the second image on a screen, and detecting means for detecting intensity of the light modulated by the spatial light modulating element and reflected by the light deflecting means via the projection optical system, the detecting means being disposed at a position that the light reflected fro

Abstract: A retinal scanning display device is disclosed which is configured to include: a light source emitting a light beam; a scanner scanning onto a viewer's retina the light beam emitted from the light source; a light exit at which the light beam scanned by the scanner exits the retinal scanning display device; and a pupil expanding element operable to expand an exit pupil of the retinal scanning display device. The pupil expanding element may be disposed at a position which is offset from an intermediate image plane occurring between the light source and the light exit, along and within an optical path defined between the light source and the light exit.

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, a first sensor configured to detect a part of the luminous fluxes deflected by the light deflecting device, one or plural first optical elements configured to be provided in the post-deflection optical system and act on the luminous fluxes deflected by all the deflection surfaces of the light deflecting device; and a second optical element having positive power in the sub-scanning direction configured to be provided in an optical path between any one of the first optical elements and the first sensor and act on the luminous fluxes deflected by all the deflection surfaces of the light deflecting device.

Abstract: An optical scanner device, comprising a scanning unit, which casts irradiation light emitted from a light source in an arbitrary direction to scan an observation object, an objective lens system, which converges the irradiation light on the observation object, and a photo-detector unit, which is disposed on an optical axis of the objective lens system to have the irradiation light transmit therethrough, is provided. A position of the irradiation light converged on the observation object is detected based on a position of a light spot of the irradiation light transmitting through the photo-detector unit.

Abstract: In an image forming apparatus provided with an optical beam scanning apparatus according to the invention, an optical beam scanning apparatus of an overillumination scanning optical system includes a semiconductor laser device as a light source, a pre-deflection optical system, a polygon mirror, and a post-deflection optical system, with a width of the luminous flux made incident on the polygon mirror being wider than a width of one reflecting surface forming the polygon mirror, wherein at least two sheets of flat plate for transmitting the luminous flux scanned by the polygon mirror are provided in the post-deflection optical system. In accordance with an image forming apparatus provided with an optical beam scanning apparatus according to the invention, not only a wave front aberration on a photoconductive drum can be suitably corrected, but suitable beam diameter and beam profile can be obtained on the photoconductive drum.

Abstract: An optical scanning apparatus includes a light source for emitting light, a deflecting device including a deflecting element for deflection-scanning a surface to be scanned with the light emitted from the light source and including a motor for driving the deflecting element, and an optical system casing including a supporting surface for disposing thereon the deflecting device and including a wall provided to stand on the supporting surface and to face the deflecting element. At a portion at which the wall stands on the supporting surface, an opening is provided so as to extending along the wall.

Abstract: An optical scanner that may assemble the lens design for varying the focus and resolution, having a light source, a reflection compound mirror, a charge coupled device, a basic objective lens and a compound lens. The basic objective lens is designed by simulation software. According to the lens design theory, the compound lens is designed. By incorporating the basic objective lens and the compound lens, different resolutions such as 1200 dpi, 1600 dpi and 2400 dpi of the optical scanner are obtained without redesigning the lens device, the current specification of the optical scanner is also varied.