Abstract: An exposure device includes a polygon motor, an f? lens, and a heat-insulating room. The polygon motor is driven into rotation while producing heat, which makes it likely that the temperature of a portion of the f? lens near a housing right wall becomes lower than that of a portion of the f? lens near a housing left wall. The exposure device further includes a recess located above the f? lens and extended in a right-and-left direction. The heat-insulating room is formed by disposing a plate above the portion of the f? lens near the housing right wall to cover the recess. Thus, the plate restricts upward heat release from the portion of the f? lens near the housing right wall.

Abstract: An oscillating mirror module as a deflecting unit is disposed so that a movable mirror faces a plane where image carriers are arranged. A plurality of light source units are disposed within a plane parallel to the plane where the image carriers are arranged so that main light fluxes of light beams emitted from the light sources form predetermined angles with each other. The oscillating mirror module includes an incidence mirror that bends a plurality of light beams emitted from the light source units to direct the light beams to the movable mirror, and a separation mirror that separates the light beams scanned by the movable mirror into two opposite directions with respect to a cross-section including a surface normal of the movable mirror and perpendicular to the rotation axis of the movable mirror. A light collecting unit collects light beams so that output optical axes of the light beams corresponding to the light source units intersect on a surface of the movable mirror of the deflecting unit.

Abstract: A compact F-theta lens suitable for precise mapping and aerial photography has an F# of not more than 4.5 and a full field of view of 60° (high quality field over) 53°. The lens is near-telecentric to less than 6°, apochromatic from 450 nm to 650 nm, and athermal from ?15° C. to +40° C. Embodiments have a focal plane diameter of 104 mm and are compatible for use with a CMOS 1.8 gigapixel multiple FPA. In some embodiments the focal length is 101 mm and the back working distance is more than 10 mm. In embodiments the lens includes three groups of optical elements, with an aperture located between the first and second groups. In some of these embodiments, the first group has at least three elements, while the second and third groups have four and three elements respectively, and the diameter of the first two groups, including housing, is less than 65 mm.

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 an optical system of an optical scanner includes a plurality of optical effective portions through which a plurality of light beams transmit, respectively, formed on at least one of an incidence surface and an exit surface in a sub scan direction, and an optical ineffective portion formed between neighboring optical effective portions not to allow the light beams to transmit therethrough, and including an area in which a local contraction occurs at a time of resin molding.

Abstract: A holding mechanism for a long length optical element, which extends in a main scanning direction that is a movement direction of a deflected luminous flux by an optical deflector, and leads the deflected luminous flux to a scanned surface, includes; a holding member which is placed in a sub-scanning direction orthogonal to the main scanning direction and holds the long length optical element in at least two places. The holding member has, an adjusting section which deflects the long length optical element in the sub-scanning direction and controls a tilt of the long length optical element in a sub-scanning cross-section and/or occurrences of a tilt distribution in a longitudinal direction in the sub-scanning cross-section.

Abstract: An optical scanning apparatus includes a light source configured to emit a plurality of laser beams from a plurality of light emitting parts, a beam shaping unit configured to shape the laser beams emitted from the light source, a detection unit provided outside the light source and configured to detect an amount of a laser beam that is not shaped by the beam shaping unit in the laser beams emitted from the light source in an area outside the beam shaping unit, and a light amount control unit configured to control amounts of the laser beams emitted from the light source based on a detection result detected by the detection unit. The detection unit includes a plurality of light-sensitive elements. The light amount control unit controls the light amounts of the laser beams emitted from the light source based on detection results of the light-sensitive elements.

Abstract: An scanning unit scanner includes a light source and a polygon mirror unit. A front-to-rear rib is disposed between the light source and the polygon mirror unit and near the polygon mirror unit. An input side opening having a slit shape is formed as a cutout in the top edge of the front-to-rear rib. When laser light from the light source passes through the input side opening, the input side opening restricts the width of the light in a main scanning direction.

Abstract: A scanning optical system including an optical source configured to generate an ultra-short light pulse, a dispersion compensation system disposed such that the ultra-short light pulse travels through the dispersion compensation system, an optical deflector configured to rotate about an axis such that the ultra-short light pulse is deflected through a scan angle, and an f-theta scan lens having a group delay (GD) variation versus relative pupil height and group delay dispersion (GDD) variation versus the scan angle that are substantially minimized. The f-theta scan lens is disposed such that the ultra-short pulse is incident on the f-theta scan lens.

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: In a scanning optical apparatus including a single lens configured to convert a beam deflected by a polygon mirror into a spot-like image on a scanned surface, an angle ?2 [deg] formed in a main scanning plane between the first optical axis and the second optical axis of the opposite lens surfaces of the lens satisfies the condition of ?0.6<?2??0.1, and at least one of the conditions ?0.5<?1<0 and ?0.1<D2<0.2 are satisfied where ?1 indicates an angle [deg] formed in the main scanning plane between the first optical axis and a reference line perpendicular to the scanned surface, and D2 indicates an amount of shift [mm] in the main scanning plane, of a point of intersection between the second optical axis and the exit-side lens surface, from the first optical axis.

Abstract: An optical device including: a laser light emitting portion that emits laser light; a polygon mirror having a reflective surface that reflects the laser light, the polygon mirror being driven to rotate and deflecting the laser light emitted from the laser light emitting portion; a first lens through which the laser light reflected by the polygon mirror is transmitted, the first lens refracting the laser light; a second lens through which the laser light having passed through the first lens is transmitted, the second lens refracting the laser light; and an adjustment unit that adjusts at least one of a length of a first optical path between the polygon mirror and the first lens, and a length of a second optical path between the first lens and the second lens.

Abstract: A laser treatment apparatus is provided which is capable of irradiating a laser beam to the position where a TFT is to be formed over the entire surface of a large substrate to achieve the crystallization, thereby forming a crystalline semiconductor film having a large grain diameter with high throughput. A laser treatment apparatus includes a laser oscillation device, a lens for converging a laser beam, such as a collimator lens or a cylindrical lens, a fixed mirror for altering an optical path for a laser beam, a first movable mirror for radially scanning a laser beam in a two-dimensional direction, and an f? lens for keeping a scanning speed constant in the case of laser beam scanning. These structural components are collectively regarded as one optical system. A laser treatment apparatus shown in FIG. 1 has a structure in which five such optical systems are placed.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a positive refraction meniscus lens of which the convex surface is disposed on a side of a MEMS mirror, the second lens is a positive refraction meniscus lens of which the concave surface is disposed on the side of the MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and time into the linear relationship between image spot distances and time. The two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a positive refraction meniscus lens of which the convex surface is disposed on a side of a MEMS mirror, the second lens is a positive refraction meniscus lens of which the convex surface is disposed on the side of the MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and time into the linear relationship between image spot distances and time. The two-element f-? lens focuses the scan light to the target in the main scanning and sub scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: An optical scanning unit used for scanning a photoconductor includes a light source, a rotatable deflector, a driver, a scan lens, an optical element, a first casing, a second casing, a first cover, and a second cover. The rotatable deflector deflects a light beam generated by the light source to scan a surface of the photoconductor. The driver rotates the rotatable deflector. The scan lens converts the light beam deflected by the rotatable deflector with equiangular motion speed to a light beam having constant speed motion. The optical element is disposed along an optical path from the scan lens to the photoconductor surface. The first casing houses the light source, the rotatable deflector, and the scan lens. The second casing houses the first casing and the optical element. The first cover covers at least the first casing. The second cover covers the optical element housed in the second casing.

Abstract: A scanning optical device includes at least one light source unit for emitting a light beam, a first deflector for deflecting the emitted light beam in an auxiliary scanning direction, a condensing optical system for generating an intermediate image of the light beam deflected by the first deflector, a collecting optical system for condensing a light beam diverged from the generated intermediate image, a second deflector for deflecting the condensed light beam in a main-scanning direction, and a scanning optical system for scanning the surface to be scanned with the light beam deflected by the second deflector. The condensing optical system has an f-? characteristic, the collecting optical system has an f-sin ? characteristic, and the scanning optical system has an f-sin ? characteristic.

Abstract: A light source apparatus includes a semiconductor laser which emits a laser beam, a coupling lens which converts the laser beam emitted from the semiconductor laser into a light flux, and a cylindrical lens into which the light flux is allowed to come from the coupling lens. The cylindrical lens is integrally formed with a lens portion, an outer circumferential portion which is arranged at an outer circumference of the lens portion, and a support portion which extends from the outer circumferential portion toward the semiconductor laser and which supports the coupling lens.

Abstract: A scanning optical system including an optical source configured to generate an ultra-short light pulse, a dispersion compensation system disposed such that the ultra-short light pulse travels through the dispersion compensation system, an optical deflector configured to rotate about an axis such that the ultra-short light pulse is deflected through a scan angle, and an f-theta scan lens having a group delay (GD) variation versus relative pupil height and group delay dispersion (GDD) variation versus the scan angle that are substantially minimized. The f-theta scan lens is disposed such that the ultra-short pulse is incident on the f-theta scan lens.

Abstract: A scanning optical system including an optical source configured to generate an ultra-short light pulse, a dispersion compensation system disposed such that the ultra-short light pulse travels through the dispersion compensation system, an optical deflector configured to rotate about an axis such that the ultra-short light pulse is deflected through a scan angle, and an f-theta scan lens having a group delay (GD) variation versus relative pupil height and group delay dispersion (GDD) variation versus the scan angle that are substantially minimized. The f-theta scan lens is disposed such that the ultra-short pulse is incident on the f-theta scan lens.

Abstract: A high precision refractive scanner includes a light source that generates a light beam, a lens pair including a stationary plano-concave lens and a movable plano-convex lens, a thin film-covered panel, and an F-theta lens that focuses the light beam that passes through the lens pair onto the panel. The plano-convex lens has an initial position where a first edge is in refracting relation to the light beam and a final position where a second edge is in refracting relation to the light beam. The plano-convex lens rotates about a pivot point that represents the origin of the respective radii of curvatures of both lenses with a nominal air gap between the two lenses. Rotation of the plano-convex lens causes the light beam to be refracted over a predetermined scan angle. A focal spot forms a scribe when it travels from a first to a second edge of the panel.

Abstract: A two-dimensional scanning projector causing a light beam to scan in a first direction and a second direction orthogonal to the first direction, comprising: a first deflector which deflects the light beam in the first direction; and a scanning optical system arranged between the first deflector and a scanned surface, wherein the first deflector is arranged such that a rotation axis of the first deflector is inclined, in a plane including an optical axis of the scanning optical system and the second direction, by a first angle with respect to the second direction, and the light beam is incident on the first deflector such that, in the plane including the optical axis and the second direction, a chief ray of the light beam entering a center of a projected image is obliquely incident on the first deflector to form a second angle with respect to the optical axis.

Abstract: A single f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit is in a meniscus shape formed by the lens in which a concave surface faces towards the side of a MEMS reflecting mirror. The single f-? lens has a first optical surface and a second optical surface, at least one optical surface is aspherical surface in both main scanning direction and sub scanning direction, and satisfies specifical optical conditions. The single f-? lens converts the nonlinear relationship between scanned angle and the time into the linear relationship between the imaged spot distances and the time. Meanwhile, the single f-? lens focuses the scan light to the target in the main scanning and sub scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A light scanning system and an image forming apparatus including the same, the light scanning system including: one or more light sources to emit light; a deflector to deflect the emitted light; and one or more f-? lenses to focus the deflected light onto a photosensitive medium, wherein the light emitted by the one or more light sources is obliquely incident on a plane perpendicular to a rotational axis of the deflector, and the f-? lens satisfies ?0.5<R1/R2<0.2, where R1 is a curvature radius of an entrance surface of the respective f-? lens in a main-scanning direction and R2 is a curvature radius of an exit surface of the respective f-? lens in the main-scanning direction.

Abstract: An optical scanning device, which comprises a light source unit, a scanning unit for scanning a scanning surface with a light from the light source unit in a first direction and a second direction orthogonal to the first direction, and an optical unit for guiding the scanning light onto the scanning surface. The scanning unit has a deflection surface which sine-wave-drives in the first direction. The optical unit has an optical surface whose arbitrary cross section in the first direction has a shape where a second order derivative of the function representing a shape of the cross section changes so as to diverge a light stronger as toward the periphery from the center. And the optical surface is configured by arranging the shape of each cross section in the first direction in the second direction.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a biconvex lens, the second lens is a meniscus lens of which the convex surface is disposed on a side of a MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and the time into the linear relationship between the image spot distances and the time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A two-element f? lens with short focal distance is used for a laser scanning unit with a polygon mirror and the two-element f? lens comprises a first lens and a second lens. The first lens is a positive power meniscus lens and the second lens is a negative power meniscus lens in the main scanning direction. The first lens has a first and a second optical surface, the second lens has a third and a fourth optical surface. Concave surfaces of the first, second and third optical surfaces are disposed on the polygon mirror side. The fourth optical surface has an inflection point in SAG counted from the optical axis to peripheral portion and its paraxial portion is convex that is disposed on the polygon mirror side. The two-element f? lens satisfies an optical condition of 0.4557?tan(?)?0.7265, wherein ? is a maximum effective window angle.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a biconvex lens, the second lens is a meniscus lens of which the concave surface is disposed on a side of a MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and the time into the linear relationship between the image spot distances and the time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A two-element f? lens with short focal distance for a laser scanning unit comprises a first lens and a second lens. The first lens has first and second optical surfaces, the second lens has third and fourth optical surfaces, and all the optical surfaces in a main scanning direction on the optical axis are aspherical surfaces. The fourth optical surface has an inflection point in SAG counted from the optical axis to peripheral portion and its paraxial portion is convex that is disposed on the polygon mirror side. The two-element f? lens satisfies an optical condition of: 0.5429?tan(?)?1.2799, wherein ? is a maximum effective window angle. The first and second lenses of the two-element f? lens with short focal distance of the invention effectively reduces the distance from the polygon mirror to an imaging surface to achieve the purpose for reducing the volume of the laser scanning unit.

Abstract: A two-element f? lens with short focal distance for a laser scanning unit comprises a first lens and a second lens. The first lens has first and second optical surfaces, the second lens has third and fourth optical surfaces, and all the optical surfaces in a main scanning direction on the optical axis are aspherical surfaces. The fourth optical surface has an inflection point in SAG counted from the optical axis to peripheral portion and its paraxial portion is convex that is disposed on the polygon mirror side. The two-element f? lens satisfies an optical condition of: 0.5429?tan(?)?1.2799, wherein ? is a maximum effective window angle. The first and second lenses of the two-element f? lens with short focal distance of the invention effectively reduces the distance from the polygon mirror to an imaging surface to achieve the purpose for reducing the volume of the laser scanning unit.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a meniscus lens of which the concave surface is disposed on a side of a MEMS mirror, the second lens is a biconcave lens, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and the time into the linear relationship between the image spot distances and the time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: This invention relates to a method of three-dimensional targeting, by galvano motor scanning head means using a combination of pre-objective and post-objective scanning techniques whereby a collimated input to collimated output beamexpander (2, 3) is used to size a beam or laser beam input into said galvano motor scanning head and a flat-field or f-Theta or telecentric lens (6) or lenses are used to focus said beam or laser beam at a target plane and where altering the separation of the elements (2, 3) within said beamexpander will alter the beam or laser beam from a collimated to a converging or diverging output into said galvano motor scanning head to alter the focal distance to said target plane.

Abstract: An optical scanning device has a light source, a unit configured to deflect a light beam from the light source; and a system including at least two scanning lenses and configured to guide the light beam deflected to a surface to be scanned. One of the scanning lenses closest to the deflecting unit has a positive refractive power in a main scanning direction and zero or approximately zero refractive power in a sub scanning direction, and another one of the scanning lenses closest to the surface has a negative refractive power in the main scanning direction, a positive refractive power in the sub scanning direction, and an incidence surface in the sub-scanning direction which is convex toward the deflecting unit.

Abstract: An optical scanning apparatus and an image forming apparatus using the same, overcoming spot rotation due to scanning line curvature and wavefront aberration deterioration, including an incident optical system for guiding beam emitted from a light source to a deflector, and an imaging optical system for forming image of the beam deflected by the deflector on a scanning surface. In sub-scanning section, the beam enters the deflecting surface obliquely to plane perpendicular to a deflector axis. Each of incident and exit surfaces of an imaging optical element is a surface in which a tilt angle of sagittal line changes from on-axis toward off-axis in sub-scanning direction, the tilt angle indicating gradient of normal to sagittal line on meridian line with respect to main scanning section. The incident and exit surfaces each have the same sign for a difference between change rates of axial and off-axial tilt angles of sagittal line.

Abstract: A light scanning unit includes: a light source generating and irradiating at least one beam corresponding to an image signal; a beam deflector deflecting and scanning the beam irradiated by the light source; and an f-? lens forming an image from the beam deflected by the beam deflector onto a surface to be scanned, the f-? lens being provided as one lens and satisfies the following equation (2): - 0.2 < SAG ? ? 1 + SAG ? ? 2 d 2 < 0.2 ( 2 ) where SAG 1 is Z value of an incident surface of the f-? lens, which faces the beam deflector, SAG 2 is Z value of the exit surface of the f-? lens, which faces the surface to be scanned, based on an XYZ coordinate system in which a main scanning plane is a Y-Z plane and a sub-scanning plane is an X-Z plane, and d2 is a center thickness of the f-? lens.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a biconvex lens, the second lens is a meniscus lens of which the concave surface is disposed on a side of a MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and the time into the linear relationship between the image spot distances and the time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a positive refraction meniscus lens of which the convex surface is disposed on a side of a MEMS mirror, the second lens is a positive refraction meniscus lens of which the convex surface is disposed on the side of the MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and time into the linear relationship between image spot distances and time. The two-element f-? lens focuses the scan light to the target in the main scanning and sub scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

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: Optical scanners are configured so a principal ray of an incident beam from a light source device to a deflector and a principal ray of a scanning beam from the deflector to a scanned surface travel on the opposite sides of an optical axis of an optical element(s) wherein entrance and exit surfaces of the optical element(s) are both concave toward the deflector in the sub-scanning section. Embodiments may beneficially separate the scanning beam from ghost light and/or be incorporated in image forming apparatuses.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a positive power meniscus lens of which concave surface is disposed on a side of a MEMS mirror, the second lens is a negative power meniscus lens of which convex surface is disposed on the side of the MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and time into the linear relationship between the image spot distances and time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A MEMS oscillating laser scanning unit (LSU) composed of a MEMS Control Module, a Pre-scan Module and a Post-scan Module is disclosed. The MEMS Control Module consists of a laser source and a MEMS oscillating mirror. The laser source and the MEMS oscillating mirror both are aligned with the same side, opposite to target surface so that laser beam emits from the side of the target surface, reverses by a reflection mirror of the Pre-scan Module and then moves along a plane formed by a central axis as well as an oscillatory rotary axis of the MEMS oscillating mirror, enters center of the MEMS oscillatory mirror. Thus, scanning spots on the target surface are all symmetrical to the central axis. Thus effective area of the MEMS oscillating mirror is reduced and further reduce the cost as well as improve scanning efficiency. Moreover, design of the f? Lens is simpler and the volume of the LSU is reduced.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a positive refraction meniscus lens of which the convex surface is disposed on a side of a MEMS mirror, the second lens is a positive refraction meniscus lens of which the concave surface is disposed on the side of the MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and time into the linear relationship between image spot distances and time. The two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a biconvex lens, the second lens is a meniscus lens of which the convex surface is disposed on a side of a MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and the time into the linear relationship between the image spot distances and the time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a meniscus lens of which the concave surface is disposed on a side of a MEMS mirror, the second lens is a biconcave lens, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and the time into the linear relationship between the image spot distances and the time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a positive power meniscus lens of which concave surface is disposed on a side of a MEMS mirror, the second lens is a negative power meniscus lens of which convex surface is disposed on the side of the MEMS mirror, at least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and time into the linear relationship between the image spot distances and time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a bi-convex lens and the second lens is a bi-convex lens. At least one optical surface is an Aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and the time into the linear relationship between the image spot distances and the time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: A light scanning unit comprises: a light source unit for emitting first and second light; a beam deflector for deflecting the first and second light emitted from the light source unit; and a synchronization detection optical system. The synchronization detection optical system includes synchronization detection sensors for detecting scanning synchronization of the first and second light and synchronization optical path converting members for converting optical paths of portions of the first and second light deflected by the beam deflector. The optical paths of the portions of the first and second light are directed to come into close proximity with one another. The light scanning unit may be incorporated in an image forming apparatus.

Abstract: A two-element f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit includes a first lens and a second lens, the first lens is a biconvex lens and the second lens is a biconcave lens. At least one optical surface is aspherical surface in both main scanning direction and sub scanning direction, and satisfies special optical conditions. The two-element f-? lens corrects the nonlinear relationship between scanned angle and the time into the linear relationship between the image spot distances and the time. Meanwhile, the two-element f-? lens focuses the scan light to the target in the main scanning and sun scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.

Abstract: To provide a technique that can appropriately correct an optical characteristic according to fluctuation in an environmental temperature.

Abstract: A single f-? lens used for a micro-electro mechanical system (MEMS) laser scanning unit is in a meniscus shape formed by the lens in which a concave surface faces towards the side of a MEMS reflecting mirror. The single f-? lens has a first optical surface and a second optical surface, at least one optical surface is aspherical surface in both main scanning direction and sub scanning direction, and satisfies specifical optical conditions. The single f-? lens converts the nonlinear relationship between scanned angle and the time into the linear relationship between the imaged spot distances and the time. Meanwhile, the single f-? lens focuses the scan light to the target in the main scanning and sub scanning directions, such that the purpose of the scanning linearity effect and the high resolution scanning can be achieved.