Abstract: A multiple beam scanning system for scanning light beams onto a photoreceptor of an image forming apparatus. A pre-polygon input and output telecentric optical subsystem includes a beam conditioning system that focuses the light beams in a cross-scan direction, collimates the beams in the scan direction, and individually focuses the beams on a polygonal mirror deflector, which reflects the beams along a first scan path. A post-polygon input and output telecentric optical subsystem redirects the scanned beams along a second scan path and through an output window onto the photoreceptor, wherein the post-polygon subsystem includes a positive cross-scan cylindrical first optical element, a negative cross-scan cylindrical second optical element, and a positive cross-scan cylindrical third optical element. In one embodiment, the three cylindrical optical elements are cylinder mirrors. In another embodiment, one or more of the optical elements are cylinder lenses.

Abstract: An image forming apparatus includes a light source provided with converting structure for converting an advancing direction of light emitted from the light source, whereby a direction in which the light source is disposed can be determined regardless of a direction in which light is emitted. The advancing direction of the light emitted from a light emitting element is converted into a direction in which light transmitting structure can transmit the light, so that a luminous intensity on a photosensitive drum can be increased. The light source is designed so as to increase a light emitting area of the light emitting element and condense light emitted therefrom. The light emitting element utilizes a flat luminous unit, which is combined with a light transmitting structure in one optical piece.

Abstract: A device for imaging a printing form in a printing form exposer, has at least one laser diode bar which has a number of laser diodes, which are each disposed along a line with nonuniform positional deviation. A spacing of the positions projected onto the line of two adjacent laser diodes differ from an intended spacing. An optical correction element is provided for changing a course of a light beam emitted by one of the adjacent laser diodes such that, downstream of the optical correction element, the beam courses of the emitted light from the two adjacent laser diodes follow the courses of two light beams from adjacent virtual laser diodes whose positions projected onto the line have a different or other spacing along the line, which have a smaller deviation in relation to the intended spacing than the spacing or is equal to the intended spacing.

Abstract: A multi-beam scanning apparatus includes a light source having first and second light source sections that hold a pair of semi-conductor laser diodes and coupling lenses that couple four beams irradiated from the pair of semi-conductor laser diodes with a base member. A light beam deviating device may be provided so as to deviate the four beams. A scan imaging device is also provided so as to scan a scan receiving surface with beam spots of the beams deviated by the light beam deviating device. A beam pitch-detecting device is also provided so as to detect a beam pitch of the respective beams formed on the scan-receiving surface. A beam pitch correcting device is provided in order to correct the beam pitch by causing relative deviation of a light axis among the respective beams on a sub scanning direction cross sectional plane.

Abstract: The optical path of scanning light E1 reaching the photosensitive drum 82a closest to the installation plane S of a plurality of photosensitive drums 82a, 82b, 82c, and 82d is provided at the photosensitive drum side with respect to the optical path of scanning light E2 deflected and scanned on the same side as the side of polygon mirror 10 for deflecting and scanning the laser beam, from the polygon mirror 10 to folding mirrors 24, 26. The invention presents a technology capable of equalizing the length of optical paths if the regulation of optical unit in height direction is different at both sides of the rotary polyhedral mirror.

Abstract: An optical recording apparatus includes a plurality of laser modules, an optical fiber array unit, a photosensitive member, and an optical system. Each laser module includes a light source and an optical fiber. The optical fiber array unit bundles a plurality of optical fibers to form an optical fiber array. The photosensitive member has a photosensitive surface. The optical system scans laser beams outputted from the array of the optical fiber array in a first direction on the photosensitive surface, the laser beams forming dots aligned in a second direction to form an angle with respect to the first direction.

Abstract: In one embodiment, a printing device includes: a print engine configured to apply marking material to print media; a laser writer configured to expose the print media to a laser beam of sufficient energy to change the reflectivity of exposed portions of the print media; a media path along which the print engine may apply marking material to print media in a macro printing zone and along which the print media may be exposed to a beam of light emitted by the laser writer in a micro printing zone; and an electronic controller operatively connected to the print engine for selectively applying marking material to the print media and to the laser writer for selectively exposing the print media to a laser beam.

Abstract: A first optical scanning device for scanning image data of colors (yellow, magenta, cyan and black) which serve as the basic for formation of color image employs an optical system having optical characteristic stable to changes in temperature in common, the optical system being incorporated in a single optical box. Inexpensive resin material is employed for its lens in a second optical scanning device for scanning image data of pale color or a special color having a large tolerance amount to color deviation or spot diameter. Further, an inexpensive second optical scanning device saving space is formed by reducing the optical path length.

Abstract: A line head, includes: a plurality of light emitting elements that are grouped into light emitting element groups, and an array that includes a plurality of imaging optical systems provided with respect to each light emitting element group which focus light beams emitted from the light emitting element groups toward a latent image-forming surface being conveyed in a second direction normal to or substantially normal to a first direction, wherein the plurality of imaging optical systems face positions on the latent image-forming surface mutually different in the second direction, and the respective imaging optical systems are constructed in accordance with differences in facing positions on the latent image-forming surface in the second direction.

Abstract: A shape or position of a shielding member is set corresponding to an image focusing property of each rod lens element to prevent an MTF from deteriorating, to provide a clear exposure image, and to prevent a defective image such as having a vertical streak or the like, from occurring on a printed image. To achieve the above, an exposure device used for an image forming apparatus of an electrophotographic type, comprises a lens array having a plurality of lens elements for condensing light from a light source onto a photosensitive drum; and a shielding member for shielding at least one portion of a peripheral portion with respect to a direction of an optical axis of each lens element from the light radiated from the light source, wherein the shielding member has a shape or a position set depending on an image focusing property with each lens element.

Abstract: Apparatus and methods for compensating for the movement of a substrate in a lithographic apparatus during a pulse of radiation include providing an optical structure configured to move a patterned projection beam incident on the substrate in synchronism with the substrate.

Abstract: A laser-marking machine comprising a main body, a beam splitter, a plurality of transmitting lines and a plurality of scanheads, wherein the main body has a laser head for producing laser light, the beam splitter is connected with the laser head on the main body, thereby laser light can be split by the beam splitter, one end of each of the transmitting lines is connected to the beam splitter, while the other end of each of the transmitting lines is connected to a corresponding one of the scanheads, thereby the laser light split by the beam splitter can be transmitted to each scanhead through each corresponding one of the transmitting lines.

Abstract: An optical scanning device has: a first optical system for converting a flux of light that has been emitted from a light source into another flux of light; a second optical system for focusing the flux of light that has been converted by the first optical system as a linear image elongated in the main scanning direction; deflecting means for reflecting and deflecting the flux of light that has left the second optical system; and a third optical system for guiding the flux of light that has been deflected by the deflecting means onto a surface to be scanned. The flux of light emitted from the light source is entered into a deflection surface of the deflecting means at a limited angle in the sub-scanning section and, by setting parameters in a manner that satisfies a given condition, the pitch unevenness can effectively be reduced in the optical systems.

Abstract: A method for manufacturing an inkjet print head with ink channels formed on a member including a piezoelectric body, and where ink is jetted from each of the ink channels by applying a voltage to electrodes provided on the piezoelectric body for each of the ink channels thereby driving the piezoelectric body. The method has the steps including adsorbing a catalyst onto the channel plate with the ink channel grooves; removing a part of the catalyst by a laser beam; and plating at least one side surface and a bottom surface of the channel plate to form a layer which serves as the electrodes, on the catalyst which has not been removed by the laser beam.

Abstract: A printing apparatus (100) for printing digital images onto a photosensitive medium (140) employing, for exposure energy, a light source (20) that uses various arrays of LEDs (32). The printing apparatus (100) may form the print image using sequential modulation, one color at a time, or by applying all colors simultaneously. Arrangements of discrete LEDs (32) may include high-intensity devices configured with collector cones (41) arranged as a multicone structure (141), with parabolic reflectors (65), or collimating lenses (36). Large area LEDs (46) may alternately be used, arranged on an angled mounting surface (64), for example.

Abstract: A polarization-direction-controlling element comprising a ½ wavelength plate disposed with a crystal optical axis tilted at substantially 45 degrees with respect to a polarization direction of a beam of light separated by a polarization-separating element with a part of a laser beam transmitted, is provided on the optical path of the laser beam, outputted from a plurality of semiconductor lasers, between an outlet for the laser beams at a fiber array and a polarization-separating element for separating the laser beam into two beams of light having mutually orthogonal polarization directions. A polarization-direction-controlling element capable of improving the quality of recorded images in an exposing-recording device using an element with polarization dependency and an exposure device capable of improving the quality of recorded images can also be obtained.

Abstract: An optical beam scanning device including a plurality of optical elements that are arranged on a housing and give a plurality of scanning lines to a plurality of photoconductor drums with an interval L is provided. Optical characteristics are designed so that intervals of the beams in the sub-scanning direction are shifted only by ?(?H?2×?F+?S)×L+?H×BP per unit temperature, where linear expansion coefficients of the housing, a frame for locating the photoconductor drums and a shaft, which is used for driving a belt or a recording medium carried on the belt on which images developed on the photoconductor are overlapped, are designated by ?H, ?F and ?S, respectively, and an interval between light beams positions on surfaces to be scanned in a sub-scanning direction as an optical path reflection is expanded by mirrors from a deflecting surface to the surfaces to be scanned is designated by BP.

Abstract: The invention is directed to the provision of an exposure apparatus that can determine a correction value for each individual light-emitting part by employing a method that detects the amount of light corresponding to one particular light-emitting part from composite light containing light rays from adjacent light-emitting parts, and also to the provision of a method for producing such an exposure apparatus.

Abstract: A laser shutting device blocks laser beams in a laser scanning unit that includes a light source that emits laser beams and a beam deflecting unit that deflects the laser beams in a main-scanning direction and is adapted to form an image on a photosensitive body using the laser beams. The laser shutting device includes a shutter movably installed in a light path between the light source and the photosensitive body, an opening formed in the shutter that allows the laser beams to pass therethrough, and a laser shutting unit that moves the shutter using an electromagnet according to a start signal for operating the beam reflecting unit so that the laser beams can pass through the opening.

Abstract: A line head, includes: a substrate which is provided with a plurality of luminous element groups which respectively include a plurality of luminous elements in a first direction which emit light beams; a lens array which includes a plurality of imaging lenses which are provided corresponding to the plurality of luminous element groups; and a light shielding member which is disposed between the substrate and the lens array and includes a plurality of light guiding holes which correspond to the plurality of luminous element groups, wherein the lens array is away from the light shielding member, an inner diameter of each of the plurality of light guiding holes in the first direction is a first light guiding hole diameter, and a bore diameter of each of the plurality of imaging lenses in the first direction is a first lens diameter, and the first light guiding hole diameter is smaller than the first lens diameter.

Abstract: An image reading apparatus includes a plurality of sensor IC chips aligned in a row. Each of the sensor IC chips incorporates a plurality of light receiving elements. The plurality of light receiving elements successively output image signals as serial analog signals corresponding to received amount of light upon receiving light from an object to be read. The number of the sensor IC chips is an integer multiple of three. The sensor IC chips are divided into blocks. The number of the blocks is an integer multiple of three. The image signals are outputted on a block-by-block basis.

Abstract: A liquid crystal optical device (liquid crystal lens) is located along the optical axis of one of two laser beams emitted by an optical pickup. The two laser beams, which are respectively modulated using a recording pulse and a drawing pulse, are coaxially emitted through the objective lens of the optical pickup, while the focal points are shifted in the light axial direction. A drawing layer and a data recording layer are laminated on an optical disk, and by controlling voltages applied to the liquid crystal optical device, the distance between the focal positions of the two beams is adjusted so that the distance equals the distance between the two layers. While this adjusted state is maintained, one of the laser beams is focused on one of the layers by a focusing actuator, and data recording and drawing are simultaneously performed.

Abstract: It is an object of the present invention to provide an optical beam scanning device and an image forming apparatus which suppress displacement of plural images formed by a different photoconductor in a sub-scanning direction by means of a simple structure even if temperature changes. The optical beam scanning device of the present invention has a single light deflecting device, a pre-deflection optical system that allows light beams from a plurality of light sources to enter the light deflecting device, and a post-deflection optical system including a first optical element for imaging reflected light beams from the light deflecting device on surfaces to be scanned for respective light beams. A second optical element, which has a positive or negative power opposite to a power of the first optical element in a sub-scanning direction, is provided in a position of the pre-deflection optical system where the light beams passes commonly and the light beams enter with distance in the sub-scanning direction.

Abstract: The invention provides a system for recording a datum onto a pixel on a light-sensitive sheet. The system essentially includes a light-emitting device and an interfering device. The interfering device has a plurality of gratings. According to the datum, at least one grating is selected from the plurality of gratings. Before the datum is recorded, the selected grating and the light-emitting device are both moved so as to align with the pixel. Then, the light-emitting device is driven to emit a light through the selected grating. Thereby, the datum is recorded on the pixel.

Abstract: An optical scanner includes a frame, a light source, an optical member, and a spacer. The light source emits a light beam. The optical member is mounted on the frame to guide the light beam to a scanning target. The spacer maintains the optical member at a predetermined position with respect to the frame. The spacer is formed of a photocurable resin that is cured in response to a predetermined light having a wavelength within a prescribed range.

Abstract: A method for driving a self-scanning light-emitting element array is provided in which two light-emitting elements may be illuminated simultaneously in one chip. In a self-scanning light-emitting element array including a transfer element array and light-emitting element array, a magnitude of the write signal for illuminating adjacent two light-emitting elements simultaneously is two times that of the write signal for illuminating one light-emitting element. The self-scanning light-emitting element array is composed of a plurality of self-scanning light-emitting element array chips arranged in a linear manner, and the two-phase clock pulses are applied commonly to the plurality of self-scanning light-emitting element array chips.

Abstract: A polarization-direction-controlling element comprising a ½ wavelength plate disposed with a crystal optical axis tilted at substantially 45 degrees with respect to a polarization direction of a beam of light separated by a polarization-separating element with a part of a laser beam transmitted, is provided on the optical path of the laser beam, outputted from a plurality of semiconductor lasers, between an outlet for the laser beams at a fiber array and a polarization-separating element for separating the laser beam into two beams of light having mutually orthogonal polarization directions. A polarization-direction-controlling element capable of improving the quality of recorded images in an exposing-recording device using an element with polarization dependency and an exposure device capable of improving the quality of recorded images can also be obtained.

Abstract: A collimation assembly is associated with a printhead housing for generating a substantially collimated laser beam. The collimation assembly comprises: a collimation housing mounted to the printhead housing to support a collimation lens; an adjustment bracket positioned adjacent the collimation housing; and a light source generating a light beam. The adjustment bracket comprises a mount member for receiving the light source such that the light beam is directed toward the collimation lens. The mount member may include first and second sections and a hinge defined between the first and second sections so as to allow the mount member to flex when receiving the light source.

Abstract: An optical multi-beam scanning device has a plurality of pre-deflection optical units, an optical path synthesizing member and an excessive light processing member. The excessive light processing member processes excessive light emitted from an excessive light emitting surface with is not an incident surface nor an emitting surface of the optical path synthesizing member. The excessive light processing member has a multi-stage taper constitution with a plurality of taper surfaces having different tilt angles.

Abstract: An electro-optical device includes an electro-optical panel which has a plurality of electro-optical elements whose light-emitting characteristics or transmissive characteristics are changed by electrical energy applied; a converging lens array which has a plurality of distributed index lenses, each transmitting light traveling in the electro-optical panel to form an erect image with respect to an image on the electro-optical panel, the images formed by the plurality of distributed index lenses constituting a continuous image; and a transmissive spacer unit which is provided between the electro-optical panel and the converging lens array so as to be bonded to them. The spacer unit includes a laminated structure of a plurality of transmissive spacer members.

Abstract: An optical scanner has a deflector, a coupling lens, a cylindrical lens, a plate through which light to and from the deflector pass, and an optical system which condenses the light deflected on a surface to be scanned. Bundles of light beams incident on the deflector have an angle between the bundles in a rotating plane of the deflector, and expressions 0.6<(?1max??)/(?2+?)<1.4, and 0.6<(?1min??)/(?2+?)<1.4, are satisfied, where ?1max and ?1min are maximum and minimum average angles of incidence on the deflecting surface, ?2 is a half-view angle, and ? is an angle of inclination of the plate in the rotating plane with respect to a main scanning direction.

Abstract: An image detection device includes a light source, an image sensor, a light guiding device, an image focusing device and a housing. The light source is configured to irradiate a pattern image with a light beam. The light guiding device is located on a first light path from the light source to the pattern image and is configured to guide the light beam irradiated by the light source to the image and further guide the light reflected from the pattern image to the image sensor along a second light path. The image focusing device is located on the second light path of from the light guiding device to the image sensor and is configured to focus the light reflected from the pattern image on the image sensor. The housing is configured to contain the light source, the image sensor, the light guiding device and the image focusing device.

Abstract: The present invention provides a light source apparatus in which wasteful cost increases can be suppressed during the manufacture of various types of light source apparatuses, and replacement of a broken light source can be performed at low cost, a recording apparatus using the light source apparatus, and an image forming apparatus comprising the recording apparatus. A plurality of optical units comprising optical members (a light source element and a lens) for outputting a single beam are combined separably in row form. A holder is used as means for holding the optical units in row form.

Abstract: An optical scanner includes a light source which emits a light beam, a reflection mirror which has a reflection surface, a first axis parallel to a main-scanning direction, and a second axis along the reflection surface and perpendicular to the first axis, and an optical element which adjusts a position of a scanning line in a sub-scanning direction, the optical element having a beam-incidence surface, a third axis parallel to the main-scanning direction on the beam-incidence surface, and a fourth axis perpendicular to the third axis and along a beam-incidence direction. A first adjustment unit is provided to rotate the reflection mirror around the second axis in order to attain uniformity of a scanning speed. A second adjustment unit is provided to rotate the optical element around the fourth axis in order to correct an inclination of the scanning line to a desired position of the scanning line.

Abstract: In an exposure head of the invention, plural first micro-focusing elements are arranged in a first microlens array so as to correspond to plural micromirrors in a DMD. An aperture array that includes plural apertures arranged so as to respectively correspond to the plural first micro-focusing elements is disposed. The apertures allow only main portions of Fraunhofer diffraction images to be transmitted therethrough. The main portions of the Fraunhofer diffraction images transmitted through the apertures are imaged on an exposure plane by second micro-focusing elements of a second microlens array. According to the exposure head of the invention, cross-talk light and scattered light can be effectively reduced, and beam diameters of beam spots projected on the exposure plane through the apertures can be adjusted to a required size.

Abstract: In an image drawing apparatus and an image drawing method for forming a desired two-dimensional pattern on an image drawing surface by using a plurality of image drawing heads, uneven density and resolution caused by errors in relative positions of the heads and installation angles thereof and by an effect of pattern distortion can be reduced. A rectangular two-dimensional pixel array is installed in each of exposure heads in an exposure apparatus (image drawing apparatus) so as to make a predetermined angle with the direction of scanning, facing an exposure surface of a photosensitive material. Combinations of slits and photo detectors detect positions of light spots in the exposure surface comprising inter-head relay areas. Pixels in the pixel arrays are selected so as to realize N-overlay exposure ideally by causing overexposure and underexposure to be minimal in the inter-head relay areas.

Abstract: An optical printhead includes a light source, a light guide, and a light collecting sheet. The light guide includes a light incident surface facing the light source and a flat light emitting surface extending in a primary scanning direction. The light collecting sheet faces the light emitting surface of the light guide and allows the passage of light emitted from the light emitting surface. The collecting sheet includes a prism layer formed with a plurality of ridges extending parallel to each other, and a base layer laminated on the prism layer. Diffused light rays emitted from the light emitting surface of the light guide pass through the light collecting sheet to become parallel rays.

Abstract: In a color laser printer, each scanner unit as an exposure scanning unit is positioned on a lateral side of a developing unit, so as not to face the surface of a photoconductor drum as a photoconductor. The scanner unit emits a laser light scanned in a direction perpendicular to a rotation axis of the photoconductor drum. A last mirror, having a reflecting surface at an angle of 45° with respect to the direction of the rotation axis of the photoconductor drum, is arranged to face the surface of the photoconductor drum. The last mirror reflects the laser light emitted by the scanner unit in the direction of the rotation axis of the photoconductor drum and changes the traveling direction by 90° to irradiate the surface of the photoconductor drum. This configuration allows a process cartridge including the developing unit to be attached and detached from above.

Abstract: Focus adjustment of an optical writing unit is performed based on an image of a test pattern formed on a paper sheet. The pattern includes bars of density levels associated with adjustment quantity information indicating numerical values corresponding to the numbers of rotation of adjustment motors and adjustment screws. The density levels decrease as the amount of displacement of the unit with respect to a photosensitive drum increases. A focus adjustment device accepts an input of the numerical values indicated beside the unprinted bars of the lowest density levels and causes the motors to turn by the numbers of rotation indicated by the input numerical values to move the unit to the position of correct focus. It is possible to perform focus adjustment of the unit with ease and high accuracy regardless of whether the unit is for forming binary or multi-valued images.

Abstract: This invention is to obtain a multi-beam scanning apparatus which always executes synchronization detection at the same timing to prevent any jitter, and an image forming apparatus using the apparatus. In a multi-beam scanning apparatus which guides a plurality of light beams emitted from a light source to an optical deflector, guides the plurality of light beams deflected by the optical deflector onto a target scanning surface through a scanning lens system, and guides some of the plurality of light beams deflected by the optical deflector to a synchronization detecting unit to execute synchronization using a sync signal obtained by the synchronization detecting unit, the synchronization detecting unit includes a BD slit which determines the synchronization detecting timing, and the BD slit has a smooth member.

Abstract: A sub-scanning interval adjusting apparatus for a multi-beam scanning unit adjusts an interval between at least two laser lines that are formed on a photoreceptor drum without causing starting points of image formation to vary. In the multi-beam scanning unit simultaneously emitting at least two laser beams by using at least two laser sources, the sub-scanning interval adjusting apparatus includes a transparent member varying in thickness depending on its height, in a direction where the laser beams pass through, the transparent member having an inclined lower side with respect to a scanning direction of the laser beams, and a movable member having an inclined side corresponding to the inclined lower side of the transparent member, thereby adjusting an interval between the laser beams by moving the movable member in the scanning direction and thus varying the height of the transparent member with respect to the laser sources.

Abstract: Disclosed is an optical scanning system and an image forming apparatus using the same, which is designed to reduce the overall size of the system and to make uniform the light spot diameter in a sub-scan direction, inside an effective scan region, as well as to ensure high-speed production of high-quality images, wherein the optical scanning system includes a light source, a condensing optical system, a deflector and an imaging optical system having one or more optical elements, wherein, in at least one optical element of the optical elements, the curvature of the opposite surfaces thereof changes continuously, inside an effective region, from the optical axis toward the peripheral portion thereof so that the sign of the curvature is reversed at the middle, and wherein, when the curvature radius of the surface of that optical element facing the deflector side, at the optical axis and in the sub-scan sectional plane, is denoted by rl0 while the least quantity of an absolute value of the curvature radius of the

Abstract: A light scanning apparatus that scans a scanned face with a light beam includes an adjusting unit that adjusts the position of a light spot of the light beam formed on the scanned face, and a compensating unit that compensates the light intensity of the light beam at the scanned face due to change caused by the adjustment of the position of the light spot. Accordingly, the light scanning apparatus can reduce or eliminate the deviation in exposure between scan lines of the multi-beam scan method and the deviation in exposure between photosensitive bodies of the tandem type image forming apparatus.

Abstract: A laser projection system is disclosed. The laser projection system includes a laser light source that is configured to selectively provide laser light. The system also includes an input beam deflection unit receiving the laser light and configured to deflect the laser light. The input beam deflection unit is configured to selectively change the angle of deflection of the laser light. A selection lens is also a part of the laser projection system and is configured to refract the laser light. A mask having at least one aperture is used. The mask receives the refracted laser light from the selection lens. A selected area of the mask is selectively illuminated by the refracted laser light. Further, a collection lens receives at least a portion of the laser light from the at least one aperture and refracts the portion of laser light.

Abstract: An optical scanning apparatus comprising a plurality of light sources, a polygon mirror for deflecting beams emitted from the light sources in a main scanning direction, lenses for imaging the deflected beams on receiving surfaces and diverting mirrors for directing the beams which passed through the lenses to the receiving surfaces. In one side of the polygon mirror, three diverting mirrors are provided in an upper optical path, and two diverting mirrors are provided in a lower optical path. In the other side of the polygon mirror, one diverting mirror is provided in a lower optical path, and two diverting mirrors are provided in an upper optical path. Thereby, bows on the receiving surfaces have the same curving direction, and color displacement can be inhibited.

Abstract: In a multi-beam scanning optical system, when at least three light fluxes emitted from a light source having at least three light-emitting points are deflected and reflected on a deflection unit and guided to a surface to be scanned by a scanning optical unit, at least three light fluxes are entered into a deflection surface of the deflection unit at irregular angles within a main-scanning section and entered into the surface to be scanned at an angle within a sub-scanning section, and provided that a variation in lengths of scanning lines which is caused when each of the at least three light fluxes is entered into the surface to be scanned at an angle within the sub-scanning section is represented as ?Y1, a variation in lengths of scanning lines which is caused when each of the at least three light fluxes is allowed to enter as a non-parallel light flux to the deflection surface within the main-scanning section is represented as ?Y2, and a variation in lengths of scanning lines which is caused from a differe

Abstract: An image forming apparatus includes a semiconductor laser array to emit a plurality of laser beams through a plurality of independently controllable laser elements according to an image signal, an imaging optical system to magnify the laser beams emitted from the laser array, and a photosensitive drum having an imaging surface to form an electrostatic latent image by being photo-exposed through the imaging optical system.

Abstract: A multi-beam scanning device is provided with a light source that emits a plurality of light beams, a polygonal mirror that deflects the light beams to scan, and an optical system that converges the deflected light beams on a plurality of objects to be scanned. The objects are arranged on a side, with respect to the polygonal mirror, in which the light beams scan, from a position closer to the polygonal mirror to a position farther from the polygonal mirror in order. The optical system further includes a plurality of optical path turning systems that turn optical paths of the deflected light beams, respectively. Each of the optical path turning systems includes a plurality of reflection surfaces, the numbers of the reflection surfaces of the optical path turning systems are all even, or odd.

Abstract: A color laser printer producing a color image using a single laser scanning unit includes a lighting unit including first and second laser diodes emitting beams of one polarization, a polarization prism transmitting or reflecting incident beams depending on a direction of polarization, and third and fourth laser diodes disposed in a different direction from the first and second laser diodes with respect to the polarization prism, a rotary polygon mirror that reflects the beam emitted along the same path from the lighting unit, an f-? lens that focuses the beam reflected by the rotary polygon mirror, first and second polarization beam splitters, each of which transmits or reflects the beam passing through the f-? lens depending on the direction of the polarization, and first through fourth photoconductive units on which the beams reflected and transmitted through the first and second polarization beam splitters are incident.

Abstract: The present invention relates to a densitometry device that can perform suitable densitometry with minimum required light amounts and can achieve space savings. An angle ? between a reference optical axis of a light source, which is an LED chip, and an optical axis, according to a photoelectric conversion element, of a density measurement optical system is set to, for example, 52°. Light-emitting chips, which emit each of red, green and blue light, are provided inside a cannon shell-shaped light-emitting portion. These light-emitting chips are arranged in a straight line along a direction of conveyance of a color patch chart. Consequently, inclination angles of the light-emitting chips with respect to a measurement axis of the density measurement optical system will always change consistently with each other, and no difference between the inclination angles of the different colors will occur.