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 illumination system includes a plurality of solid state light emitters and a scanner operative to sequentially receive light from the plurality of solid state light emitters and to provide a time-multiplexed light output. The solid state light emitters are each operated in pulse mode to increase their brightness relative to the light output of similar emitters operating in continuous mode. The time multiplexed light output is a generally continuous output having a brightness that is greater than the brightness of the output of similar emitters operating in continuous mode. The time multiplexed light output is useful in photolithography and machine vision applications.

Abstract: An aspect of the present invention includes a method for patterning a workpiece covered at least partly with a layer sensitive to electromagnetic radiation, comprising the actions of, providing a data representation of at least one image to be imaged onto a plurality of locations of said workpiece, fracturing said data representation into a plurality of field stripes, repeating the actions of rasterizing a first field stripe of said data representation, modulating a modulator according to said rasterized field stripe, imaging said first field stripe onto a plurality of locations of said workpiece, rasterizing a second field stripe of said data representation while imaging said first field stripe onto said plurality of locations of said workpiece, terminating the repetition when a predetermined amount of said image is imaged onto said plurality of locations of said workpiece. Other aspects of the present invention are reflected in the detailed description, figures and claims.

Abstract: The present invention provides a method of observing a specimen in a field of view of an electron microscope comprising the acts of illuminating the specimen with an electron beam having a first angle and forming a first transmission image of the specimen in the field of view and adjusting the electron beam to a second angle and forming a second transmission image of the specimen in the field of view and calculating a degree of coincidence between the first and second transmission images.

Abstract: High quality images are provided without the occurrence of image quality defects due to reciprocity law failures, even when scanning a multi-beam. When interlaced scanning is employed, it is possible to select combinations such that, taking any freely selected neighboring scanning lines, respective scan numbers of the neighboring scanning lines are always different. Thus, a duration of scanning spacing can be made to be at least the duration of a single main scan. As a result, image defects such as banding due to reciprocity law failures can be greatly alleviated, and images can be provided in which image defects are to unlikely to be noticed in practice.

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 light scanning unit having a simple structure and a low-priced multi-beam shape is provided. The light scanning unit includes a composite light source in which a plurality of light sources for emitting coherent light having different wavelengths are arranged adjacent to one another and the optical axis of each light source are arranged substantially parallel to each other, such that the composite light source emits light at a divergence angle centering on an optical axis. The plurality of coherent emitted light comprising a light beam.

Abstract: A light scanning apparatus capable of printing with a high quality and an image forming apparatus using the same are obtained. The light scanning apparatus is provided with an incidence optical system for guiding a light beam emitted from a light source part to a deflection part; an imaging optical system provided with a diffracting surface having a power at least in a sub-scanning section that guides the light beam deflected by the deflection part on a surface to be scanned; and a surface inclination correction function, in which a principal ray of the light beam is always positioned outside of a main scanning section during scanning. In the light scanning apparatus, each element is set so as to satisfy each conditional expression.

Abstract: An optical scanner includes a light source modulated based on image data, an optical deflection and scanning part deflecting a light beam emitted from the light source, and a scanning and imaging optical system condensing the deflected light beam toward a scanning surface so as to form a light spot optically scanning the scanning surface. The effective scanning region of the scanning surface is divided into a plurality of regions according to a scanning line curving characteristic. Suitable image data for optically scanning the divided regions are selected from image data of a plurality of image lines every time the light spot optically scans the effective scanning region, so that the image data of each of the image lines is written with scanning line curving being corrected.

Abstract: In an exposure apparatus of the invention, for a spatial light modulator, each of a plurality of pixel portions fewer than the total number of the pixel portions is controlled with a control signal generated according to exposure information. Namely, a part of the pixel portions is controlled without controlling a whole of the pixel portions on the substrate. Thus, the number of pixels in the pixel portions is decreased, and transfer time of the control signal becomes short. This enables modulation speed of the laser beam to be increased and the high-speed exposure to be performed. An incorporated laser light source, in which the laser beams are incorporated and struck on the optical fiber, is preferable to the laser device. By adopting the incorporated laser light source, high brightness and high output can be obtained, and it is preferable to the exposure of the spatial light modulator. Since the fiber array is obtained with few optical fibers, it is low cost.

Abstract: An optical scanning device, including a resin lens having a power that is an inverse power of scanning lens placed before a deflector. A bundle of rays emitted from a plurality of light sources is coupled into a desired state by coupling lens, after which the bundle of rays is incident on the resin lens. The surface of incidence of the resin lens has a spherical surface with a negative power, and the exit surface of this resin lens has a cylindircal surface with a negative power only in the sub scanning direction. The bundle of rays passes through the resin lens and enters a glass toroidal lens. A light deflector deflects the bundle of rays from the toroidal lens. The deflected bundle of rays is incident on a third optical system that condenses the deflected bundle of rays onto a surface to be scanned.

Abstract: A multiple-beam scanning device of the present invention includes a light source unit provided with a plurality of light sources. A deflector deflects, in the main scanning direction, light beams issuing from the light sources. Optics condenses the light beams deflected by the deflector with optical devices having power in the subscanning direction main scanning direction, respectively, in such a manner as to establish a preselected beam spot diameter, and returns an optical path with at least one mirror for thereby scanning a subject surface. An adjusting device provides, in a plane formed by scanning lines deflected by the deflector, one of the optical devices with ? eccentricity about the center of an optical axis in the direction of the optical axis.

Abstract: A beam scanner is operable to scan light in two or more axes, typically in a raster pattern that includes a fast scan axis and a slow scan axis. Plural beams of light are scanned, each beam of light producing a scanned region that at least partially overlaps at least one adjoining scanned region. Scanned regions may be aligned to adjoin and overlap along a dimension corresponding to the slow scan axis. The beam scanner may comprise a scanned beam display and/or a scanned beam image capture device. In a display, the power level of overlapping displayed pixels may be scaled to provide smooth transitions between adjoining regions to improve the image quality presented to a viewer. In an image capture device, one or more detectors is operable to collect light scattered from adjoining regions and a controller is operable to produce an image from the scanned regions.

Abstract: A plurality of beams scan the photosensitive body or the like so that a high quality image whose streak is not recognized by a human eye can be formed. 2m lines are formed simultaneously in Nth time, (N+1)-th time, and (N+2)-th time scannings respectively. At this point, the m lines are fed in a sub-scanning direction at each termination of one-time scanning, and the next scanning is performed. Accordingly, a region which is exposed twice between the scannings is generated at an m-line period.

Abstract: The invention relates to a device, a method and a corresponding computer program product for transmitting data to a carrier. The device (1) comprises a control system (2), a holding surface (3) which is used to hold the carrier (4) and a transmission head (5) for transmitting data from a data memory (6) to said carrier (4). The holding surface (3) is arranged in such a way that it can be rotated about an x-axis (8) by means of a first drive device (7) and the transmission head (5) is arranged in such a way that it can be moved along a y-axis (10) by means of a second drive device (9). Both the holding surface and the transmission surface are controlled by the control system (2) in a coordinated manner.

Abstract: A multibeam light source for use in information recording, including a semiconductor laser array provided with a plurality of light emitting points in a single package, in which the plurality of light emitting points are positioned in linear relationship to one another and have an equidistant pitch so as to respectively emit laser beams to be simultaneously scanned over a recording substrate. The position of the semiconductor laser array is adjustable so as to satisfy the relation ??tan?1{1/(n?1)}, where the angle ? is defined by two straight lines, the one drawn perpendicular to the primary scanning direction on an image recording substrate and the other drawn through respective centers of the first and n-th laser beam spots formed on the image recording substrate by projecting laser beams emitted respectively from the plurality of light emitting points.

Abstract: An exposure system is provided that surrounds a photopolymer on a rotating cylinder ablation system. The exposure system linearly follows the ablation source and operates to expose the ablated (masked) plate with high intensity illumination from all sides so as to continuously expose all points on the photopolymer.

Abstract: There is provided a multi-beam scanning device including a first, a second and a third light emitting elements which emit a first, a second and a third light beams, respectively, and a prism unit through which the first, second and third light beams respectively emitted by the first, the second and the third light emitting elements pass. The prism unit includes at least two prisms being bonded to each other, a first reflective portion and a second reflective portion being formed on a surface on which said at least two prisms are bonded to each other. Further, the prism unit has a gap formed between the first reflective portion and the second reflective portion, the third beam emitted by the third light emitting element passing through the gap.

Abstract: An optical scanning apparatus which has a scanning position detecting section in which a plurality of light receiving sensors are arranged at predetermined spaces in a direction substantially perpendicular to the scanning direction without being overlapped in the scanning direction and each of the light receiving sensors has a shape in which a side into which scanning light of a laser beam is entered is substantially perpendicular to the scanning direction, an opposite side is slanted with respect to the scanning light, and at least one of recess is provided to the slanted side, and it is detected that pulse widths of respective output signals obtained by scanning the scanning position detecting sensor composed of the light receiving sensors with the scanning light of the laser beams are smaller than a predetermined pulse width, so that the resolution in the sub scanning direction of the lasers can be easily adjusted with a simple algorithm.

Abstract: An optical scanner includes a light source modulated based on image data, an optical deflection and scanning part deflecting a light beam emitted from the light source, and a scanning and imaging optical system condensing the deflected light beam toward a scanning surface so as to form a light spot optically scanning the scanning surface. The effective scanning region of the scanning surface is divided into a plurality of regions according to a scanning line curving characteristic. Suitable image data for optically scanning the divided regions are selected from image data of a plurality of image lines every time the light spot optically scans the effective scanning region, so that the image data of each of the image lines is written with scanning line curving being corrected.

Abstract: A scanning system uses a multi-beam brush having a widely separated beams, a modulator that controls intensity of pixels in scan beams, an optical system that minimizes scan line bow at the expense of non-uniform scanning beam velocity, and a timing generator that generates a pixel clock signal having a variable period that compensates for the non-uniformity of pixel velocity. The wide separation of scan beams permits the modulator to turn beams on or off with a direction of brightening or darkening in the cross-section of the beams being opposite to the scanning direction. A novel arrangement of the beams in the brush permits a uniform indexing step size to uniformly expose an image region.

Abstract: A system and method for selectively process material on a processing surface of a printing form to create a fine structure or pattern for images or text. At least one fiber laser comprising a pump source and a laser fiber is provided. A laser gun is mounted adjacent the printing form and has at least a focusing optics. The fiber laser outputs a laser beam which is diffraction-limited to permit the focusing optics to focus the laser beam onto the processing surface of the printing form as a spot having a spot size sufficiently small to process the processing surface to create the fine structure or pattern images or text.

Abstract: An optical multi-beam scanning device includes three or more light sources, a pre-deflection optical unit for providing a predetermined characteristic for each light beam emitted from the light sources, each pre-deflection optical unit being disposed so that a height of an optical path in a sub-scanning direction and an angle in the sub-scanning direction differ, a within-set combining unit for combining the optical paths by reflecting certain light beams being components of a set, and a light deflection unit for deflecting the plurality of light beams via the within-set combining unit in the main-scanning direction by reflection of a same surface.

Abstract: An image forming apparatus includes an electrophotographic developing device, a photosensitive body, a precharger for precharging the photosensitive body, and exposing units of two optical systems with different light amount distributions, which are provided for one photosensitive body for forming electrostatic latent images on the photosensitive body. The exposing units are selectively used.

Abstract: An imaging method for a printing form (32) is described, with one or more laser diode bars (10) with n individually controllable laser diodes (12) each of which are assigned to one imaging channel, in which the laser diodes (12) of a laser diode bar (10) are divided into a main field (14) of m and into an auxiliary field (16) of (n-m) laser diodes (12) in such a way that an imaging channel (44) in the auxiliary field (16) with a matching feed that can be activated is assigned to each imaging channel (44) in the main field (14) that cannot be activated. In order to create a row (40) of m printing dots (38) on a setting line (36) at even distances a by means of the imaging channels (44), printing dots (38) are set by the main field (14) at a first time, and by the auxiliary field (16) at least at a second time. The imaging channels (44) are shifted relative to the printing form (32) parallel to the setting line (36) between the imaging times.

Abstract: An optical beam scanning device includes plural light sources, a pre-deflection optical unit, a light deflection unit, a post-deflection optical unit, and a horizontal synchronization unit. One of the formed plural latent images is formed by plural light beams while the other latent images are respectively formed by one light beam, and the light deflection unit deflects the light beams forming the plurality latent images by one surface or integrally processed surface thereof. The horizontal synchronization unit is on a position of an upstream side of scanning lines forming the latent image formed by the plural light beams and deflects that the light beam forming the latent image formed by the plural light beams reaches a predetermined position. The image forming apparatus employs the optical beam scanning device and controls timing to form images by the respective light beams with reference to a moment when the light to be detected reaches a predetermined position.

Abstract: In a simultaneous multibeam scanning system, composite beams are formed by using two semiconductor laser arrays each of which can singly output a plurality of beams. An optical system is enabled to scan beams of the number, which corresponds to the sum total of output beams of each of laser light sources, in a scanning plane. A stabilization control means for maintaining the interval between adjacent scanning beams at a uniform value is introduced into this optical system.

Abstract: An optical scan apparatus includes an optical deflection unit (4), an image formation optical system (3), and curved surface mirrors (7a to b 7d). Light fluxes from the image formation optical system (3) come onto the deflection surface (4a) of die optical deflection unit (4) in an oblique direction. Light fluxes from the optical deflection unit (4) come onto the curved surface mirrors (7a to 7d) in an oblique direction. When a boundary is a plane (6) including a normal at the center of the deflection surface (4a) and parallel to the main scan direction, the curved surface mirrors (7a to 7d) are arranged in the same space divided by the boundary and the scan speeds of fluxes scanning the surfaces to be scanned (8a to 8d) are almost identical. Thus, it is possible to obtain identical drive frequencies of the light sources (1a to 1d), thereby simplifying the circuit.

Abstract: An image forming apparatus is constructed to include an image bearing member which is rotatably supported to bear a toner image, a light beam scanning section to simultaneously scan the image bearing member by a plurality of light beams so as to form an electrostatic latent image, a developing section to develop the electrostatic latent image into the toner image, a transfer section to transfer the toner image onto a recording medium, and an ON start timing adjuster to adjust an ON start timing of one of the plurality of light beams, based on an image tone of each of a plurality of patterns of an image pattern formed by the light beam scanning section.

Abstract: A multibeam scan apparatus includes a light source having semiconductor laser diodes and coupling lenses arranged in a main scan direction. The semiconductor laser diodes are positioned so that light beams emitted by the semiconductor laser diodes substantially cross each other at a point. A light beam restricting unit shapes the light beams from the laser diodes through the coupling lenses so that the light beams have a given spot size. The light beam restricting unit is positioned close to the above-mentioned point. A scan lens causes the light beams reflected by a polygonal mirror to form images on a scanned surface.

Abstract: In a scanning optical system, a plurality of laser beams pass through an imaging optical system and converge on surfaces to be scanned, respectively. The imaging optical system includes a scanning lens and a plurality of long lenses for the respective beams. The scanning lens has an anamorphic aspherical surface, and each long lens has at least one two-dimensional polynomial aspherical surface.

Abstract: An illumination system includes a plurality of solid state light emitters and a scanner operative to sequentially receive light from the plurality of solid state light emitters and to provide a time-multiplexed light output. The solid state light emitters are each operated in pulse mode to increase their brightness relative to the light output of similar emitters operating in continuous mode. The time multiplexed light output is a generally continuous output having a brightness that is greater than the brightness of the output of similar emitters operating in continuous mode. The time multiplexed light output is useful in photolithography and machine vision applications.

Abstract: It is an object of the present invention to realize a multi-beam optical scanning device which is suitable for high speed and high recording density by almost completely offsetting and correcting a deviation of focusing positions in a main scanning direction of plural spots in an entire surface to be scanned without deteriorating focusing properties at all.

Abstract: A color image forming apparatus is provided with a semiconductor laser array 1 of which laser beam emitting points 1-1˜1-12 are arranged m (m≧2) in the row direction thereof and n in the line direction thereof as the same number of the photosensitive drums 9; a beam splitting means 4 which splits the respective laser beams for every lines on the semiconductor laser array 1 so that m laser beams emitted from one of the rows on the semiconductor laser array 1 scan a same photosensitive drum 9 among thereof; and a beam deflection means 6 which deflects in common n laser beams for every lines emitted from the semiconductor laser array 1 and irradiates the same onto the respective photosensitive drums 9, wherein, the arrangement direction of m beam spots irradiated onto one of the photosensitive drums 9 is inclined by an angle &agr;2 with respect to the main scanning direction, thereby, through the common use of the scan optical system for the plurality of laser beams the size and cost of the apparatus ar

Abstract: A display or image capture apparatus includes a scanning assembly that scans about two or more axes, typically in a raster pattern. A plurality of light sources emit light from spaced apart locations toward the scanning assembly and the scanning assembly simultaneously scans more than one of the beams. The light sources are positioned so each beam illuminates a discrete region of the image field that is substantially non-overlapping with the other regions. Each line of the image is formed from segments where two or more of the segments define a line of an image. Because the lines are made from discrete segments, the problem of raster pinch is reduced. The achievable resolution of the display for a given scan angle and mirror size is increased relative to a mirror sweeping a single beam. Segments of different wavelengths can be overlapped to produce a color display.

Abstract: A scanning system uses a multi-beam brush having a widely separated beams, a modulator that controls intensity of pixels in scan beams, an optical system that minimizes scan line bow at the expense of non-uniform scanning beam velocity, and a timing generator that generates a pixel clock signal having a variable period that compensates for the non-uniformity of pixel velocity. The wide separation of scan beams permits the modulator to turn beams on or off with a direction of brightening or darkening in the cross-section of the beams being opposite to the scanning direction. A novel arrangement of the beams in the brush permits a uniform indexing step size to uniformly expose an image region.

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 emitted by the light source to scan, and an optical system that converges the deflected light beams on a plurality of objects to be scanned. The optical system includes an optical path turning system that turns optical paths of the deflected light beams, respectively. The optical path turning system is constructed such that optical path lengths of the optical path of the deflected light beams are the same, and one of the optical paths directed to an object located farthest from the polygonal mirror consists of two linear paths and one turning portion at which a beam is deflected.

Abstract: A multi-beam scanning device including a multi-beam light source including plural laser diode arrays emitting plural laser beams and at least one coupling lens; a deflector configured to deflect the plural laser beams; an optical system configured to guide the deflected plural laser beams to an image forming surface; a body configured to contain the multi-beam light source, deflector and scanning optical system; and an adjustment member located between the body and the multi-beam light source and configured to adjust the beam pitch of the plural laser beams in the sub-scanning direction. An image forming apparatus including an image bearing member, the above-mentioned scanning device and an image forming device.

Abstract: A method and an apparatus for exposing photosensitive material, in particular for exposing a printing form, in which a surface to be exposed of the photosensitive material is scanned by at least one light beam. The light beam is emitted by a light source and, before striking the photosensitive material, is optionally modulated, interrupted and/or deflected. An exposure head is provided and moved at a constant distance from the surface in relation to the latter and to the light source in order to scan the surface of the photosensitive material with the light beam. In order to make the exposure head as light as possible, after the light beam has emerged from the light source substantially parallel to the surface to be exposed, the light beam is deflected through a gaseous medium toward the exposure head and there should be reflected onto the surface.

Abstract: A method and a device for imaging a printing form (48) via at least two imaging modules (40,418) which each have at least one light source are disclosed for avoiding the banding effect that an imaging in a transition region (416). The two imaging modules (40,418) are provided in such a manner that a number of at least partially not-simply connected printing dots are produced in the transition region (416) by the first imaging module (40) and the complementary, not-simply connected printing dots are produced in the transition region (416) by the second imaging module (418).

Abstract: Light source and light beam scanning units with reduced deviation of beam positions over time and ambient conditions, in use for image forming apparatuses. In the light source unit for emanating light beams, including a plurality of LEDs and coupling lenses each corresponding to the LEDs, there are provided lens holders having two supporting faces aligned approximately parallel to the optical axes of the coupling lenses, elastic members for abutting the coupling lenses by pressing the side portions thereof onto the supporting faces, light source support members for holding LEDs corresponding to the coupling lenses, and bolts for fixing the light source support members. Following the proper adjustment of the position of the lens holder in the vertical direction with respect to the optical axes of the coupling lenses, the light source support members is fixed onto lens holder by bolts.

Abstract: A light scanning device includes an optical element that images, on an image holding body, a light beam emitted from a light source. The light scanning device further includes a holding member that holds the optical element, and scanning line curve correcting mechanism for correcting the optical element in a sub scanning direction to correct a scanning line formed by the light beam in the sub scanning direction. The light scanning device further includes a scanning line inclination correcting mechanism for entirely tilting the optical element to correct an inclination of the scanning line. At least one part of the scanning line curve correcting mechanism, and at least one part of the scanning line inclination correcting mechanism are provided integrally with the holding member.

Abstract: An object of the present invention is to provide a scanning optical system capable of reducing the number of its components and its size with a simple construction, and an image forming apparatus using the scanning optical system. In a specific scanning optical system, a plurality of light beams emitted from a plurality of light source units are deflected and scanned by a plurality of different deflecting facets of a common optical deflecting unit, and a plurality of scanned surfaces are scanned with the light beams deflected and scanned by the different deflecting facets, respectively.

Abstract: Multiple light beams are reflected by a resonant oscillator through an optical system onto light sensitive drums of a printing system. Information is encoded onto the beams, and an image is printed based on the encoded information. Preferably four beams and four drums are used to print four colors. The oscillator includes an oscillating plate mounted on the torsion springs for resonant oscillation. A magnet is mounted on the oscillating plate and an oscillating magnetic field oscillates the magnet and the plate. Sensors detect the position of at least one of light beam to synchronize the operation and speed of the encoder, drums and oscillator. The oscillator may include multiple reflective surfaces on one or more sides of an oscillating plate, and one or more beams may be reflected from each surface.

Abstract: The method and apparatus record an image on a recording medium attached around the outside surface of a drum rotating at a first constant speed by main-scanning the recoding medium in a main scanning direction with a group of two-dimensionally disposed light sources and exposing the recording medium as well as auxiliary-scanning the recording medium by moving the group of light sources in an auxiliary scanning direction substantially perpendicular to the main scanning direction. The method and apparatus move the group of light sources in the auxiliary scanning direction at a second constant speed and deflect light from the group of light sources for exposing the recording medium in a direction inclined at a predetermined angle &thgr; with respect to the main scanning direction in synchronism with the movement of the recording medium in the main and auxiliary scanning directions with respect to the group of light sources.

Abstract: A scanning system uses a multi-beam brush having a widely separated beams, a modulator that controls intensity of pixels in scan beams, an optical system that minimizes scan line bow at the expense of non-uniform scanning beam velocity, and a timing generator that generates a pixel clock signal having a variable period that compensates for the non-uniformity of pixel velocity. The wide separation of scan beams permits the modulator to turn beams on or off with a direction of brightening or darkening in the cross-section of the beams being opposite to the scanning direction. A novel arrangement of the beams in the brush permits a uniform indexing step size to uniformly expose an image region.

Abstract: Internal drum recording apparatus provided with a rotating deflecting element, comprising two (or more) beams of different wavelengths, which are simultaneously operatable, and optical elements for bringing the two or more beams to a common optical path before they reach the rotating deflecting element. The deflecting element may have dispersing properties such that beams of different wavelengths will leave it at slightly different angles. The beams of different wavelengths may be generated by laser diodes or tunable laser diodes. The apparatus may further comprise a beam combiner to combine the beams generated by the light sources.

Abstract: In a multibeam scanner, a control unit includes a velocity detecting circuit detecting a conveying velocity V of a photosensitive body; a comparison circuit comparing the detected conveying velocity V to a reference conveying velocity V0; a light intensity control circuit 93, a modulation circuit 94, an LD1 control circuit 95, and an LD2 control circuit 96. The LD1 control circuit 95 and LD2 control circuit 96 issue drive signals to laser diodes LD1 and LD2. The laser diodes LD1 and LD2 emit laser beams LB1 and LB2 that are modulated according to image signals outputted from the modulation circuit 94. The laser beams LB1 and LB2 are deflected by a polygon mirror onto the photosensitive body and perform a main scan over neighboring scanning lines SL1 and SL2, while the photosensitive drum is rotated. The light intensity from the laser diode LD1 is adjusted when the velocity of the photosensitive drum differs from a prescribed velocity in order to achieve a balanced image density.

Abstract: An image forming apparatus includes an image bearing member, a latent image writing device that emits a plurality of laser beams, two adjacent laser beams of the plurality of laser beams partially overlapping in a sub-scanning direction, respectively, and forming a reference latent image on a surface of the image bearing member by performing repeated scanning of each laser beam on the surface of the image bearing member, a developing device that develops the reference latent image with toner into a reference toner image, and a detecting device that detects the density of the reference toner image. The quantity of light of each laser beam forming a subsequent latent image is adjusted according to the density of the reference toner image detected by the detecting device.

Abstract: The present invention is directed to a method and apparatus for exposing photosensitive material to form high quality continuous tone and/or color images thereon. The preferred apparatus includes an imaging head comprised of a plurality of red light sources, a plurality of green light sources, and a plurality of blue light sources. The light produced by said green light sources is passed through a first filter having a narrow spectral transmission characteristic in the green spectral range. Similarly, the light produced by said blue light sources is passed through a second filter having a narrow spectral transmission characteristic in the blue spectral range.