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: An exposure head includes a light emitting element and a imaging optical system having a first region and a second region and contrived such that a slope of a long dimension of a spot diagram formed by light emitted from the light emitting element that passes through the first region is different from a slope of a long dimension of a spot diagram formed by light emitted from the light emitting element that passes through the second region.

Abstract: P-polarized light beam passing through an f? lens passes through a polarization beam splitter, is converted into S-polarized light beam by a quarter-wave plate and a reflecting mirror, re-enters the polarization beam splitter, and is reflected at the polarization beam splitter in the ?Z direction. An optical path of a light beam between a polygon mirror and the f? lens, between the f? lens and the polarization beam splitter, between the polarization beam splitter and the quarter-wave plate, between the quarter-wave plate and a reflecting mirror, between the reflecting mirror and the quarter-wave plate, and between the quarter-wave plate and the polarization beam splitter are in the same plane.

Abstract: A light emitting substrate has a plurality of first light emitting portions arranged in a main scanning direction and a second light emitting portion disposed in a direction intersecting the main scanning direction with respect to the array of the plurality of first light emitting portions. A lens array has a plurality of first lenses, each of which is disposed to face each of the plurality of first light emitting portions, and a second lens for the second light emitting portion. A direction of the emitted light from the second light emitting portion has a slope with respect to a straight line which extends perpendicularly from a light emitting face of the corresponding second light emitting portion.

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 optical element used in an optical scanning apparatus includes a diffracting surface composed of a diffraction grating. The diffracting surface includes a diffraction grating having a sectional shape linearly formed. If diffraction power in a main scanning direction on the diffracting surface received by an axial light flux is ?DO and refractive power in the main scanning direction on a refracting surface on which the diffraction grating is formed received by the axial light flux is ?ref, the optical element satisfies the following conditions: 0<?DO<1.8×10?3(1/mm), and 0.5|?DO|<|?ref|<1.5|?DO|, where the diffraction power ?DO and the refractive power ?ref have opposite signs.

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: Provided are a light scanning unit and an electrophotographic image forming apparatus employing the same. A possible form deviation during fabrication of a cylindrical lens employed by the light scanning unit is reduced by intentionally giving a form deviation to the incident surface and the emission surface of the cylindrical lens in the main scanning direction.

Abstract: An optical scanning device includes: a light source; an optical deflecting unit that deflects a light beam emitted from the light source to scan on a scanning surface in main-scanning direction; and a scanning optical system that includes a first scanning lens and a second scanning lens that converge the light beam that is deflected onto the scanning surface. Distance between an exit surface of the first scanning lens and an incident surface of the second scanning lens is shorter than distance between a deflection facet of the optical deflecting unit and an incident surface of the first scanning lens, an exit surface of the second scanning lens is nearer to the deflection facet than a midpoint between the deflection facet and the scanning surface, and an image-surface-side principal point of the scanning optical system in sub-scanning direction is nearer to the scanning surface than the midpoint.

Abstract: An image forming apparatus includes an image carrier having a curvature in a first direction; and an exposure head including a first light emitting element that emits a light having a wavelength ?11 and a light having a wavelength ?12, a first optical system that converges each of the light emitted from the first light emitting element onto the image carrier, a second light emitting element, and a second optical system that converges a light emitted from the second light emitting element onto the image carrier, wherein a position at which the first optical system converges each of the light and a position at which the second optical system converges the light are different from each other with respect to the first direction.

Abstract: A line head includes first to third light-emitting elements arranged in a first direction; and an optical system that forms images by light emitted from the first to third light-emitting elements on an imaging surface to form images of the light-emitting elements, in which the first light-emitting element is arranged between the second light-emitting element and the third light-emitting element in the first direction; the optical system has a first lens surface that has refractive power and is arranged so as to satisfy a relation of H>0.

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 multi-beam optical scanning device includes a light source device, a deflector for deflecting a plurality of light beams from the light source device, and an imaging optical system for imaging a plurality of light beams deflected by the deflector upon a photosensitive drum, wherein a plurality of light beams, when they pass through an imaging optical element having a largest positive power in the sub-scan direction, pass through positions which are spaced apart from each other in the sub-scan direction, and wherein the photosensitive drum is so disposed that, when, among the plurality of light beams passing through the imaging optical element having a largest positive power in the sub-scan direction, a light beam which passes through a position furthermost in the sub-scan direction from a meridional of the imaging optical element having a largest positive power in the sub-scan direction is incident on the photosensitive drum, an incidence angle thereof in the sub-scan direction with respect to a surface nor

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: An optical system of a line head images light emitted from first and second light emitting elements and includes a rotationally symmetric lens having a lens face. A first region of the lens face includes an intersection point of the lens face with the symmetry axis of the lens, and a second region surrounding a periphery of the first region. The shape of a boundary portion between the first and second regions has the relationship 0.5?<??, wherein ? is a first direction angle that a first chief ray emitted by the first light emitting element makes with a second chief ray emitted by the second light emitting element, and ?? is an angle that a tangent line to the first region at the boundary portion makes with a tangent line to the second region at the boundary portion in a first direction cross-section including the symmetry axis.

Abstract: An image forming apparatus includes a line head that performs exposure on a latent image carrier to form a latent image. The line head includes first and second light-emitting elements arranged in a first direction; and an optical system that images light emitted from the first and second light-emitting elements. When a difference between the maximum and minimum values of a longitudinal aberration of the optical system is G, a distance in the first direction between centers of geometry of the first and second light-emitting elements is Pel, and an optical magnification of the optical system is ?, a relation of G>|?|·Pel is satisfied.

Abstract: At least one exemplary embodiment is directed to an optical scanning apparatus which includes a Vertical Cavity Surface Emitting Laser including a plurality of light-emitting portions that are spaced from each other in at least a sub-scanning direction, a first optical system including a light-condensing element that converts each of light beams from the laser into a light beam in another state; a deflector that reflects and deflects the light beams from the first optical system, and a second optical system that focuses the light beams deflected by the deflecting member on a surface to be scanned, where the second optical system includes at least an imaging optical element having an optical surface with a non-arc shape in a sub-scanning cross section.

Abstract: The optical scanning apparatus has at least two scanning units S1 and S2 which are arranged so as to oppose each other with a deflecting unit interposed therebetween. The scanning units include incident optical systems La and Lb that guide light beams emitted from light source units 1a and 1b to the deflecting unit 4, and imaging optical systems Ma and Mb that cause the light beams for scanning deflected on a deflecting surface of the deflecting unit to form images on surfaces 8a and 8b to be scanned. The two scanning units are configured such that the main scanning planes thereof including an optical reference axis C0 have different heights from a bottom surface 4c of the deflecting unit in the direction of the rotational axis of the deflecting unit.

Abstract: An exposure head, includes: a lens array that includes a light transmissive substrate whose length in a first direction is greater than a length thereof in a second direction orthogonal to the first direction, a first lens that is arranged on the light transmissive substrate, and a second lens that is arranged on the light transmissive substrate at the first direction of the first lens, the first lens and the second lens being connected in the first direction; and a head substrate that is provided with a first light emitting element that emits a light toward the first lens and a second light emitting element that emits a light toward the second lens.

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 includes a light source, a pre-deflection optical system, a polygon mirror, and a scanning optical system. The pre-deflection optical system includes a coupling lens and a diffraction lens. A light output surface of the coupling lens is a phase shifting surface, while a light output surface of the diffraction lens is a diffractive surface. The absolute value of the focal length of the diffraction lens is longer than the absolute focal length of the coupling lens.

Abstract: A line head includes a positive lens system having two lenses, image-side and object-side lens arrays, a light emitter array on an object side of the positive lens system, and an aperture plate that forms an aperture diaphragm. Where the row number of lenses arrayed in a second direction is ‘m’, a gap between effective regions of two image-side lenses adjacent to each other in a first direction is ‘?’, an image-side angle of aperture is ‘?i’, a width of light-emitting elements images in the first direction is ‘Wi’, a focal length of the image-side lens is ‘f2’ and a distance from an image-side principal plane of the image-side lens to an image surface is ‘Si’, the following conditions are satisfied: f2?(mWi??)/(2?i), Wi?2Si?i/(m?1)+?/(m?1).

Abstract: A lens array includes: a lens array substrate having a light transmissive property; a first lens disposed on the lens array substrate; and a second lens disposed on the lens array substrate in a first direction from the first lens and different from the first lens in peripheral shape.

Abstract: A lens sheet has an external shape of a rectangle or a square defined by four sheet ends in a vertical direction thereto. The lens sheet includes: a first surface, on which a plurality of lenses extending in a direction inclined to one of the sheet ends are arranged in parallel with each other; and a second surface opposite to the first surface, on which a printing is to be performed or to which a printed medium is to be stuck.

Abstract: An optical scanning device for guiding a light beam to a member to scan the member with the light beam, including a light source emitting the light beam; a light deflector deflecting the light beam; a focusing optical system including a plastic optical element molded using a die. The optical element has least two transfer surfaces formed by contacting with transfer surfaces of the die and including a light entrance surface and a light exit surface; and a third surface including a non-transfer surface formed without contacting a transfer surface of the die. The light beam passes through the optical element in such a manner that the optical axis center of the light beam extends in a direction parallel to the shorter side of the optical element while being shifted from the dimensional center of the optical element toward the third surface of the optical element.

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: Lens pairs include: a first lens to form an intermediate image, which is an inverted image of an object, on an intermediate image plane; and a second lens to form an image of the object, which is an inverted image of the intermediate image, on the image plane. A ratio of SO1 (the distance between the first principal plane of the first lens and the object plane) to SI1 (the distance between the second principal plane of the first lens and the intermediate image plane) is substantially the same as the ratio of SI2 (the distance between the second principal plane of the second lens and the imaging plane) to SO2 (the distance between the first principal plane of the second lens and the intermediate image plane). The distance between the first lens and the object plane is different from a distance between the second lens and the imaging plane.

Abstract: An exposing device includes a light-emitting element array including plural light-emitting elements disposed in a first direction and a second direction orthogonal to or substantially orthogonal to the first direction, a lens array including plural lenses that focus lights from the light-emitting elements, a supporting member that supports the light-emitting element array and the lens array, and an exposure-position adjusting mechanism including a rotation adjusting unit that rotates the supporting member around or substantially around an axis in the first direction.

Abstract: An image forming apparatus includes a plurality of image carriers and an optical writing device including light sources that emit light beams of different wavelengths, a deflector that deflects the light beams emitted from the light sources and synthesized on an identical axis in a sub-scanning direction, a first beam separator, a second beam separator, a first imaging device, and a second imaging device. The first beam separator and the second beam separator are located between the first imaging device and the second imaging device and transmit or reflect the light beams according to travel directions or wavelengths thereof. One of the targets is scanned with the light beam transmitted through the second beam separator. Another target is scanned with the light beam reflected by the second and first beam separators. The first and second imaging devices narrow the beams in the main scanning direction and the sub-scanning direction, respectively.

Abstract: Disclosed is an optical scanning device including a light source including multiple light-emitting elements, the multiple light-emitting elements being arranged in a linear manner, a collimator lens to collimate a light beam from the light source, a light-deflecting device to deflect a light beam having passed through the collimator lens to a medium to be scanned and scan the medium with the light beam, and a rear optical system arranged in an optical path between the collimator lens and the medium to be scanned, wherein the collimator lens deviates an image surface in a direction opposite to an image surface deviation on the medium to be scanned by a nearly same amount as the image surface deviation, the image surface deviation being caused by a change of an image height of the light source, and the change being caused by the rear optical system.

Abstract: A lens array includes: a light transmissive lens array substrate; a plurality of lenses disposed on the lens array substrate in a first direction; and a line-like mark formed on the lens array substrate in a second direction one of perpendicular and substantially perpendicular to the first direction.

Abstract: A line head includes: a first lens formed from a resin and on a glass substrate; and a light emitting element substrate that has light emitting elements arranged in a first direction, wherein a cross section of the first lens taken in the first direction and including an optical axis of the first lens has a configuration wherein a curvature of the first lens at the optical axis has a larger absolute value than a curvature of an outer peripheral portion of the first lens.

Abstract: A lens sheet has an external shape of a rectangle or a square defined by four sheet ends in a vertical direction thereto. The lens sheet includes: a first surface, on which a plurality of lenses extending in a direction inclined to one of the sheet ends are arranged in parallel with each other; and a second surface opposite to the first surface, on which a printing is to be performed or to which a printed medium is to be stuck.

Abstract: The conventional lens array of an erecting unit magnification system is composed of an inside lens of spherical shape and an outside lens of spherical or aspherical shape, and has a problem to be improved for the resulting MTF performance. A lens array of an erecting unit magnification system is provided by stacking a first and a second planar-shaped lens array plates. Each of the first and second planar-shaped lens array plates includes a plurality of outside lenses (L1 and L4), which are regularly arranged on one side thereof, and a plurality of inside lenses (L2 and L3), which are regularly arranged on the other side thereof. Especially, the outside lenses (L1 and L4) and the inside lenses (L2 and L3) are formed based on the defining method according to the present invention.

Abstract: An image forming apparatus has a calibration mode in which a calibration image is formed on a print medium to correct image forming conditions. The image forming apparatus detects print medium information to determine, on the basis of the print medium information, whether the print medium is a sheet recommended as a print medium for use in the calibration mode. The image forming apparatus sets calibration conditions corresponding to the determined recommended sheet. The image forming apparatus corrects the image forming conditions on the basis of the set calibration conditions.

Abstract: An exposure device is provided that has a light emitting unit having a plurality of light emitting elements and a lens array having a pair of lenses having a first lens and a second lens, the lens array having a shielding unit for shielding a light from any one of the pair of lenses, wherein a formula EC<EP/2 is satisfied, where EP denotes an interval between two adjacent light emitting elements of the plurality of light emitting elements and where EC denotes an off-set between a central axis of the first lens and a central axis of the second lens.

Abstract: A line head, includes: a head substrate that includes a first light emitting element and a second light emitting element; and a lens array that includes a first positive lens that images a light emitted from the first light emitting element on a specified plane and has a lens surface of a free-form surface, and a second positive lens that images a light emitted from the second light emitting element on the specified plane and has a lens surface of a free-form surface, each of the lens surfaces of the first and the second positive lenses having focal points with different focal lengths.

Abstract: A disclosed optical path switching device includes a polarization bistable VCSEL that emits a beam having a rising polarization plane, a laser light source configured to emit a beam having a polarization plane orthogonal to the rising polarization plane, and an optical path switching unit configured to switch an optical path of the beam emitted from the polarization bistable VCSEL by switching the angle of the rising polarization plane of the beam emitted from the polarization bistable VCSEL. The beam emitted from the polarization bistable VCSEL is incident on an entrance window of the optical path switching unit, and the beam emitted from the laser light source is incident on an exit window of the polarization bistable VCSEL.

Abstract: A first beam separation device is arranged either to allow the light beams to enter and pass or to reflect the light beams in accordance with a direction of entrance of the light beams. A second beam separation device is provided either to allow or to reflect the light beams having passed through the first beam separation device in accordance a wavelength thereof. The light beam passing through the second beam separation device scans one of plural scan objectives and the light beam reflected by the second beam separation device is further reflected by the first beam separation device and then scans the other one of the plural scan objectives. A first imaging device is provided to correct a f-theta (f?) performance and a curvature of an imaging plane to enable the light beams to scan the plural scan objectives at a constant speed. The first imaging device is integral with the first beam separation device.

Abstract: An f-? lens is joined to a mount through a light curable bond, forms an incident deflected beam onto a photosensitive body, and includes a lens part which has an incident side on which the deflected beam is incident, and an exiting side which is disposed near the photosensitive body and on which the entered deflected beam is exited, an joining part which has a joining side which is extended from the incident face and is joined to the mount, and an emitting side which is extended from the exiting face and disposed to face the joining side, and which a light beam for curing the light curable bond is scanned, and an emitting part which is formed on the emitting side in a non-planar shape and provided to decrease loss of light quantity of the light beam scanned on the emitting face, so that the f-? lens provides an improved joining force in a joining process by a light cure joining type.

Abstract: An optical scanning device is disclosed, including: a light deflection part, an imaging optical element, a variable focus optical element, and a focal point control device. The light deflection part repeatedly deflects and scans a light flux emitted from a light source on a scan surface. The imaging optical element forms an image in a vicinity of the scan surface with the light flux. The focal point control device changes a focal distance of the variable focus optical element, which is arranged in an optical path from the light source to the light deflection part, in executing each of deflection scans, and correct an image misalignment on the scan surface due to an optical path difference for each scan angle.

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: A multi-beam scanning device is disclosed that is able to realize a stable and small beam spot and realize stable scanning line intervals between plural light beams. The multi-beam optical scanning device includes a first optical system which has a first lens for coupling the light beams from the light sources, and a second lens which is an anamorphic element having power at least in a sub scanning direction and for guiding the light beams from the first lens to the deflection unit; and a second optical system. At least the second lens includes a diffracting surface having power.

Abstract: A multi-beam optical scanning device which enables uniform scan line pitch and high precision image, includes a light source having plural light emitting members, a rotary polygonal mirror having a deflecting surface, a first optical system for imaging a light beam on the deflecting surface and a second optical system for imaging the light beam on a scan surface to be scanned, wherein the optical axis of the first optical system is disposed at a particular angle in a sub-scan section with respect to a plane perpendicular to the deflection axis of the deflecting surface, and wherein, with respect to the imaging magnification in the sub-scan section of the second optical system on the optical axis and between the deflecting surface and the scan surface, the imaging magnification at a scan start side is made large while the imaging magnification at the scan end side is made small or, alternatively, the imaging magnification at a scan start side is made small while the imaging magnification at the scan end side i

Abstract: A lens array, includes: a plurality of lens substrates which include a plurality of lenses arranged in a first direction; and a support member which supports the plurality of lens substrates arranged in the first direction.

Abstract: There is provided a light beam scanning apparatus which deflects a light beam from a light source by using a deflector and scans the surface of a photosensitive member with a focused light beam. The light beam scanning apparatus includes a first electro-optical element placed on the optical axis of the light beam between the light source and the deflector. The first electro-optical element includes an electro-optical crystal and transparent electrodes respectively provided on surfaces of the electro-optical crystal which oppose each other in the optical axis direction.

Abstract: An optical scanning unit that includes a first optical device that forms collimated light from light radiated from a light source, a second optical device that focuses the collimated light onto a deflector, and an imaging optical device that focuses light deflected by the deflector onto an exposure object. The optical scanning unit further includes a refraction unit and a diffraction unit, and the power of the refraction unit is ?r, the power of the diffraction unit is ?d, and the ratio ?r/?d is such that 0.5<?r/?d<1.3.

Abstract: A lens array, includes: a clear substrate; and a plurality of plastic lens substrates each of which includes a plurality of lenses and which are arranged on at least one of surfaces of the clear substrate.

Abstract: In an optical scanning device, a lateral magnification in a direction corresponding to a sub scanning direction of an optical system is adjusted to be small by a coupling optical system that includes a first lens and a second lens. As a result, scanning by a plurality of light beams can be performed with high precision while avoiding high costs.