Abstract: A rotary apparatus includes a stator portion, a rotor portion rotatably supported by the stator portion and including a permanent magnet, a ring-shaped stator core arranged opposingly to the permanent magnet and including a plurality of electromagnetic coils wound around a plurality of locations of the stator core discretely existing along its circumferential direction, and a ring member for supporting a free end of the stator core.

Abstract: A beam scanning apparatus of an electrophotographic color printer having first and second light sources, and a deflecting unit including a driving source and first and second beam deflectors. The driving source has a rotation shaft and the first and second beam deflectors are coaxially installed on the rotation shaft and respectively deflect and scan beams of light emitted from the first and second light sources. First and second beam correcting units are arranged along the path of light between the deflecting unit and a photoreceptor and respectively correct the beams deflected by the first and second beam deflectors.

Abstract: A system and method for controlling registration between different printing plates or printing cylinders in a printing press which includes a camera with a lens having at least two zoom settings and a control unit for changing the zoom setting of the camera in accordance with a distance between registration marks printed on a printed substrate found in at least one image acquired by the camera.

Abstract: An apparatus for imaging books or other bound volumes which includes a book supporting system and an optical system positioned above the book supporting system and mounted for movement along a vertical axis toward and away from the book support system. The book support system includes an inner platform and an outer platform with the inner platform being mounted for vertical movement relative to the outer platform. A cradle having pivotable side support plates is mounted on the inner platform, and support arms are mounted on the outer platform. The support arms are positioned so that the support plates rest thereon so that as the cradle is moved downwardly, the support arms pivot the side support plates upwardly.

Abstract: A printer for use in exposing a photosensitive material and method of operation thereof. The printer includes a rotatable polygon mirror having a plurality of adjacent facets. The mirror includes a reference facet and signal generator for generating a polygon index signal which defines a reference position. A light source for directing a light beam is provided for reflection of the beam off each of the adjacent facets for exposing the photosensitive material and defining a writing path. A sensor is also provided for generating a line start signal for each of the facets in response to the light beam passing over the sensor. The printer is provided with a switch for placing printer in a first set-up mode or writing mode. When in set-up mode a counter measures a first time period T.sub.S from the polygon index signal to a first line start signal generated by the reference facet. A counter also measuring a second time period T.sub.

Abstract: A laser pattern generator for semiconductor mask making or direct writing of features on a semiconductor wafer uses a pulsed laser source to achieve high power and short wavelength (e.g. 263 nm or less) radiation, for writing very small-sized features. The laser pulse frequency is either synchronous or asynchronous to the writing grid of the features being written, in various embodiments.

Abstract: A technique for marking pixels on workpieces by routing a scanned beam to different marking stations to mark individual pixels on the workpieces. A diffractive scan lens focuses the beam. A mark is formed on a workpiece by producing the mark and curing the mark. Angular position of a scanning mirror in a raster scanner is determined by moving a beam, reflected from the scanner, across rulings on an optical element during scanning. A print head for printing spots on a surface of a workpiece has a walled, internally pressurized chamber and structure for causing an inked web to conform to a contour of the chamber wall and to be pulled along the chamber wall. A print head has a compliant-walled, internally pressurized chamber. A print head has a chamber having a low-coefficient of friction coating. Two workpieces may be marked at two marking stations by two-directional scanning.

Abstract: A scanning optical apparatus has a stationary shaft and a rotary sleeve rotatably fitting to each other. The apparatus is arranged to deflection-scan a light beam by rotating a rotary polygon mirror attached to the rotary sleeve. In the apparatus a second permanent magnet, which is repulsive to a first permanent magnet mounted on the stationary shaft, is disposed on a lower end side of the rotary sleeve. Further, a third permanent magnet is placed on a base to which the stationary shaft is fixed so that the third magnet can provide a repulsive force in a direction to urge the second permanent magnet toward the first permanent magnet.

Abstract: Correcting motion quality induced color banding problems resulting from photoreceptor motion defects in a color imaging device having a laser based multifaceted polygon and a rotating cylindrical mirror whose rotation is set by a controlled rotation inducing element. A motion sensor senses the motion of the photoreceptor. Based upon motion errors a controller either advances or delays the production of a latent image. The controller further controls the rotation inducing element, beneficially a piezoelectric element, such that a latent image is produced in a predetermined location. When multiple latent images are produced, the controller beneficially causes the latent images to be properly registered.

Abstract: A magnet is integrally formed with a mirror surface for reflecting off a laser beam. A torsion spring holds the magnet thereon. The torsion spring is made of a shape-memory alloy. A coil generates an alternating magnetic field so as to oscillate the magnet about the torsion spring. The oscillating magnet scans the light beam.

Abstract: An item of office equipment, such as a facsimile machines, is provided having image analysis and laser printing capabilities with a shared mechanical image scanning apparatus. Embodiments include a single assembly with an analysis head and a laser emitting source disposed facing each other, a revolving mirror interposed between them, and first and second returning mirrors disposed symmetrically with respect to a line along which the analyzing head and the laser emitting source are disposed, such that the revolving mirror is located substantially at a point constituting an operational centre of symmetry of the single assembly. This symmetrical design allows the single analysis/printing assembly to be structurally simple and compact, enables the number of photosensors and LEDs necessary for image analysis to be reduced to as few as one of each, and eliminates the need for analog shift registers, thus decreasing the cost, size and complexity of the device.

Abstract: A system and method of providing a periodic trajectory scan path for a laser beam across a photoconductive surface in a laser printer. A preferred embodiment of the periodic trajectory for a system with a two-axis deflector includes a multiple-frequency omega wave trajectory for providing a substantially rectangular grid of available dot locations for selective laser beam pulsing. As such, a plurality of generally linear rows of dots are completed in a single scan pass of the laser beam across the surface. The periodic trajectory is provided by deflecting the laser beam with an optical beam deflector, such as an electro-optic deflector, placed between the laser and the rotating polygon scanning mirror. A preferred embodiment of the beam deflector includes a folded optical path.

Abstract: A system and method of deflecting a laser beam in a laser printer for providing enhanced resolution and reduced banding effects. Specifically, to enhance resolution, the laser beam is borrowed (deflected) from a white space area adjacent an image to double resolution at the edges of the image. Similarly, banding is reduced by deflecting the beam to compensate for drum rotational and translational errors. The beam is deflected using an electro-optic modulator placed between the laser diode and the scanning mirror. Encoders detect drum rotational errors and motion between the optics unit and the drum to provide a closed loop feedback system for reducing banding.

Abstract: In a deflecting/scanning apparatus, a rotating polygon mirror is rotatably supported by an air bearing constituted by a stationary shaft and a rotating sleeve which are made of a ceramic material. An upper portion of an end face of the rotating sleeve is covered with a lid as a separate member. A vent hole formed in the lid is sealed with an adhesive to form an air damper chamber.

Abstract: Scanning optical device is provided with a light source unit, a deflector for deflecting light beam from the light source, a deflector driving circuit for driving the deflector and an optical housing for accommodating the deflector and the deflector driving circuit. The device is further provided with a cover for closing the optical housing. The cover is provided with an opening through which the deflector driving circuit is exposed to the external air. The hole in the cover is constituted by a tubular partition wall integrally formed with the cover.

Abstract: Apparatus and methods for exposing multilayered thermal imaging media to eliminate "cloud" or "woodgrain" artifacts by proper optimization of the exposing radiation angle of incidence. The exposure angle of incidence is large enough so that all rays with high reflectance loss are paired with equally many with low reflectance loss to increase printing efficiency.

Abstract: A beam passing position controlling apparatus comprises a light source for emitting a beam, a mechanism for reflecting the beam toward an image carrier surface to scan the image carrier surface, a sensor for detecting a position where the beam passes on the image carrier surface, a circuit for calculating a correction amount from the position detected, a mechanism for correcting the passing position of the beam on the basis of the correction amount, and a circuit for controlling respective operations of the apparatus.

Abstract: An image forming apparatus includes a light beam generator for generating a light beam, a rotational polygon mirror for scanning the light beam generated by the light beam generator across a member to be illuminated, a rotation detector for detecting whether or not the rotational polygon mirror rotates at a predetermined rotation number for an image formation, and a determining device for determining whether or not the rotational polygon mirror rotates at the predetermined rotation number stably in accordance with an output from the rotation detector.

Abstract: A laser printer is provided having an automatic printhead identification system for use in a family of laser printers that are compatible with more than one model of printhead. For example, a single laser printer model can be made so that two different printheads can be successfully used, so long as the printer system knows which laser printhead has actually been installed. To detect which printhead has been installed, the printer operating system provides a reference clock signal having a pre-determined frequency, which dictates the rotational speed of the motor. Once the motor has achieved a "lock" operational speed, the printer measures the scan rate of the faceted mirror by detecting the time interval between pulses of the "HSYNC" signal. The HSYNC signal is sent to a "divide-by-n counter" circuit which divides the pulse frequency of the HSYNC signal, thereby increasing the time interval (by a factor of "n") that must be sensed by the system to determine which printhead is in fact installed.

Abstract: A feedback control regulator including a regulated device, a sensor for providing a feedback signal representing a characteristic of the regulated device, and a reference signal. An interpolator provides mathematically manipulated feedback and reference signals and a summing function responds to the mathematically manipulated feedback and reference signals for providing and error signal. In particular, the feedback signal is augmented by 2x and the reference signal is augmented by 2x plus 1. A controller responds to the error signal for adjusting the characteristic of the regulated device.

Abstract: A dynamic-pressure gas bearing structure includes a sleeve, a column-like shaft fitted to the sleeve, and a plurality of shallow grooves formed on the outer peripheral surface of the shaft and extending in the axial direction of the shaft. The shallow grooves are formed by grinding in which grains are aligned to the aforementioned axial direction. An optical deflection scanning apparatus is provided with such dynamic-pressure gas bearing structure.

Abstract: A laser beam printer of the present invention has a laser exposing unit including apochromatical plastic cylinder lenses being integrally formed by adhesion of plastic of the same material as a f.theta. lens or molding, having negative power in a sub-scanning direction, a substantially flat surface contacting air, and first and second f.theta. lenses in which surfaces other than a toric surface are displaced in the same direction in the sub-scanning direction and a toric surface is displaced in the direction opposite to the other surfaces in the sub-scanning direction and a different inclination is provided for each of the lenses. The plastic cylinder lens and the glass cylinder lens may be inversely arranged.

Abstract: A magnetically preloaded air bearing motion system for an imaging system motion system includes a carriage for moving a scanning means along a rigid spar for reflecting an optical feed beam onto media. The carriage includes a pair of orthogonal walls for engaging the orthogonal walls of the spar and an air bearing system disposed therein. The air bearing includes a plurality of permanent magnets secured in a prearranged pattern to the orthogonal walls of the carriage for providing an attractive force to couple the carriage to the spar. The carriage further includes a series of passageways terminating at a plurality of output orifices arranged in a predetermined pattern on the orthogonal walls of the carriage. Compressed air is system is electrically connected to the linear motor for controlling the movement of the carriage along the spar.

Abstract: A system and method for controlling registration between different printing plates or printing cylinders in a printing press which includes a camera with a lens having at least two zoom settings and a control unit for changing the zoom setting of the camera in accordance with a distance between registration marks printed on a printed substrate found in at least one image acquired by the camera.

Abstract: A V-shaped scanning head, a book support, and a scanner that includes the V-shaped scanning head and the book support. The V-shaped scanning head comprises a pair of scanning surfaces angled relative to each other to form a V-shaped scanning face. An image capturing means preferably in the form of a pair of angled photoelectric detector arrays or a pivotable scanning arrangement is provided for capturing images of both sides of a book, the images being received through the scanning face. Processing circuitry, typically provided in the scanning head, processes the signals received from the image capturing means. The book can be supported on a movable book support that is capable of adopting a V-shaped configuration to support the open book.

Abstract: The improved beam scanning apparatus has an optical element that is driven to rotate by means of a drive means so as to be capable of continuous angular displacement with respect to the beam from a light source. The optical element deflects the incident beam so that it is focused to form image on the image plane. It is provided with an entrance face, a reflecting face and an exit face which have their shape specified in such a way as to achieve effective correction of aberration, provide higher resolution, and reduce the size and cost of the apparatus.

Abstract: A novel laser printer is disclosed, in which heat generating parts are positively cooled while reducing the noise generated by a blowing mechanism. A rotor of the motor for rotating a scanning mirror of a scanning device is surrounded by a cover. An air flow inlet port and an air flow outlet port are formed on the sides of the cover. The space in the proximity of the air flow inlet port and the air flow outlet port is divided by an air flow separation member. One longitudinal end of the air flow separation member is close to the rotor and the other longitudinal end and the lateral ends thereof are connected to the cover. The air flow separation member partially divides the rotating air flow generated around the rotor in the proximity of the air flow outlet port, and generates the discharge air flow, which in turn is discharged out of the cover. A suction air flow is introduced from the air flow inlet port to the interior of the cover which is now negative in pressure, in the form of the rotating air flow.

Abstract: An apparatus for positioning a laser deflector in a laser writer, the apparatus comprises a rotatable spindle assembly for receiving the laser deflector. A frame encloses a portion of said spindle assembly, and two adjustable members are integrally attached to the frame, and the members include a tapered end which contacts the laser deflector for moving the laser deflector which, in turn, positions the laser deflector on said spindle assembly.

Abstract: Apparatus for exposing and processing a photographic recording material, generally called imaging element, comprising (i) an exposing part, generally called imagesetter, in which the imaging element is imagewise exposed, and (ii) a processing part, generally called processor, in which the imaging element is wet processed, characterized in that the exposed imaging element is fed automatically from the imagesetter into the processor and in that the processing is carried out along a substantially vertical path. Also disclosed is a method for recording an image by using the above described apparatus for exposing and processing an imaging element.

Abstract: An optical system for a beam scanning apparatus comprises a laser beam, a cylindrical first lens, a scanning mirror rotatable about an axis for deflecting and scanning the focused energy beam and a concave, toroidal mirror adapted to deflect the focused energy beam from the rotating mirror and collimate the beam. The toroidal mirror has a radius in a major axis equal to the focal length of the first lens and a radius in a minor axis equal to twice the focal length of the first lens, and is spaced from the first mirror a distance equal to the focal length of the first lens. Preferrably, the axis of rotation of the scanning mirror is non-orthogonal with respect to the direction of the beam from the first lens.

Abstract: A device for producing a printing stencil, in particular a screen printing stencil, having a rotatably supported printing cylinder, a laser for generating a laser beam incident on the printing cylinder and capable of being displaced in the longitudinal direction of the printing cylinder, and focusing optics to focus the laser beam onto the surface of the printing cylinder. The focusing optics have at least one deflection mirror with an elastically deformable mirror diaphragm. At least one sensor is provided to measure a distance between itself and the surface of the printing stencil. An actuating signal generator generates an actuating signal as a function of the measured distance. Actuating devices set a curvature of the mirror diaphragm as a function of the actuating signal.

Abstract: An apparatus includes a media handler which is capable of processing a supply of media sheets which can take the form of plates, aluminum or plastic used in lithographic printing presses or the like, or can be film which is advanced to a drum and scanned by a scanning process and thereafter removed from the drum surface by appropriate handling means.

Abstract: A laser beam is projected from a laser oscillator 1 and converged by a condenser lens 2. The laser beam converged by the condenser lens 2 is reflected in any arbitrary direction by a scanning mirror 4 which is rotated by scanning means 3. The laser beam is linearly moved. The laser beam is reflected by a curved surface reflecting mirror 5 which is formed in a spherical surface in the primary scanning direction of the laser beam and an ellipsoid in the secondary scanning direction so that the scanned surface is scanned at a substantially predetermined speed.

Abstract: In an image reading apparatus, an optical unit goes out from a reference stop position, reads an image from a document, and returns to the reference stop position. A position sensor detects a position of the optical unit and output a trigger signal when the optical unit comes to a predetermined position. There is provided a frequency divider to divide a frequency of a pulse signal used to detect the rotations of a driving motor, a pulse width detector to detect the divided pulse width in response to the trigger signal, and a rectifier to rectify an braking amount applied onto the driving motor in accordance with the pulse width so that the optical unit is stopped at the reference stop position.

Abstract: An image recording apparatus in which at least one light beam scans over an inner surface of a cylindrical member to record an image on a recording medium held on the inner surface. A light beam from light beam outputting means advances along a central axis of a cylindrical member and enters an optical head which includes deflecting means and an imaging optical system. The deflecting means and the imaging optical system rotate as one unit. The nodal point of the imaging optical system is located at or close to a point on the central axis which is nearest a beam irradiation position on the recording medium. Hence, displacement of the imaging position is prevented which makes it possible to record a high quality image, even if the optical head wobbles.

Abstract: An imaging apparatus has a support shoe with an at-least-partially cylindrical inner surface for receiving a recording media, a rotor which is simultaneously rotatable about and linearly translated along a fixed axis, a write head assembly carried by the rotor to write on recording media received on the inner surface of the support shoe, a member having an arcuate outer periphery and supported within the support shoe for movement along the fixed axis, and electrically conductive bristles extending radially from the periphery of the member toward the received media to dissipate electrostatic charge build up on the media. The member is supported for movement with the rotor, and preferably leads the rotor as the rotor moves along the axis during a write operation. The bristles extend radially from the periphery of the member and are spaced from the received media to create an electrical stress in free air space.

Abstract: Apparatus and methods for exposing multilayered thermal imaging by proper optimization of the exposing radiation angle of incidence of a coherent radiation source to eliminate "cloud" or "woodgrain" artifacts stemming from local differences in printing efficiency across a sheet of the multilayered imaging media. A media is mounted to an exposure surface and exposed with a scanning coherent Gaussian laser beam at an angle other than normal incidence. The angle of incidence of the exposing beam is intentionally made large enough so that all rays with high reflectance loss are paired with equally many with low reflectance loss to increase printing efficiency. This efficiency occurs over a range of angles between 21 and 25 degrees, with some benefit beginning at 16 degrees.

Abstract: A laser plotter having the ability to cut registration holes while the medium is in a plotting location within the laser plotter is disclosed. The plotter includes laser plotting apparatus and laser cutting apparatus whose axes of rotation are identical. The laser plotting and laser cutting apparatus can utilize the same or different optical paths. The laser plotting apparatus can perform raster and vector scanning motions.

Abstract: An optical scanning device including a semiconductor laser and a scanning optical system which transmits a laser beam emitted from the semiconductor laser and scans the laser beam on a photosensitive drum. The scanning optical system includes at least one hologram having relief on at least one surface with the ratio h/P of the depth h and the minimum pitch P of the relief being set to about 1 or less in an area of the hologram surface the laser beam irradiates.

Abstract: The disclosure relates to a laser marking system, using a displaceable mirror to cause the path of the laser beam to scan in one direction. The mirror is conveniently controlled by at least one flexure hinge driven by a piezo electric device, an electro-strictive device or a magneto-strictive device. In one disclosed embodiment two mirrors (15,16,) are provided, each mirror (15 or 16,) having a flexure hinge device (18,19) individual thereto, and the displacements applied to the flexure hinge devices (18,19,), via respective driving devices (20,21,), cause the mirrors (15,16,) to scan the path of the laser beam (13) in a series of steps in one direction of scan. A computer (11), arranged to drive the flexure hinge driving devices (20,21,), also controls the firing of the laser (12) in accordance with a predetermined program.

Abstract: A laser pattern inspection and/or writing system which writes or inspects a pattern on a target on a stage, by raster scanning the target pixels. Inspection can also be done by substage illumination with non-laser light. A database, organized into frames and strips, represents an ideal pattern as one or more polygons. Each polygon's data description is contained within a single data frame. The database is transformed into a turnpoint polygon representation, then a left and right vector representation, then an addressed pixel representation, then a bit-mapped representation of the entire target. Most of the transformations are carried out in parallel pipelines. Guardbands around polygon sides are used for error filtering during inspection. Guardbands are polygons, and frames containing only guardband information are sent down dedicated pipelines. Error filtering also is done at the time of pixel comparisons of ideal with real patterns, and subsequently during defect area consolidation.

Abstract: A laser beam optical scanning system having a laser diode, a collimator lens, a cylindrical lens, a polygonal mirror and an f.theta. mirror. The f.theta. mirror has a free toric surface whose curvature in the main scanning direction varies in accordance with field angle. The variation of the curvature of the free toric surface is set in accordance with the position of the f.theta. mirror in the optical path, and this appropriate setting of the variation of the curvature enables the f.theta. mirror to correct both distortion and curvature of field in the main scanning direction.

Abstract: A light scanning device for scanning a scanned medium in a main scanning direction with a light beam has a detachable scanning unit having a reflecting mirror and a resonant light deflector. The scanning unit has a first adjusting mechanism for tilting the reflecting mirror about one axis to correct for a bow and an offset of a scanning line on the scanned medium in an auxiliary scanning direction substantially perpendicular to the main scanning direction, and a second adjusting mechanism for tilting the resonant light deflector about two axes to correct for a bow, a lean and an offset, respectively, of the scanning line on the scanned medium. When the resonant light deflector is to be replaced, the scanning unit is replaced with a new scanning unit which has already been adjusted. Therefore, the whole process of replacing the scanning unit can easily and quickly be carried out.

Abstract: A laser beam printer includes a movable mirror which is rotated by a scan mirror motor. Laser light is alternately deflected toward an information reading station and an information writing station by applying the laser light to the movable mirror from a semiconductor laser. The laser light is switched between writing-use light and reading-use light at the time the movable mirror is rotated through a predetermined angle. In the laser beam printer having the semiconductor laser which is used for both writing and reading information, information is written and read out during one rotation of the movable mirror. It is therefore possible to perform a reading operation and a writing operation simultaneously by simply switching the laser light at the predetermined time depending on the rotation angle of the movable mirror.

Abstract: A scanning motor includes a fixed shaft made of a ceramic material. The rotary sleeve is rotatably fitted onto the material, and a rotary sleeve also made of a ceramic fixed shaft so as to be rotatable about the fixed shaft. The motor further includes a thrust plate fixed to one end portion of the rotary sleeve. At least an abutting surface of the thrust plate faces an end surface of the fixed shaft. The motor further includes a driver for rotating the fixed sleeve. At least one of the end surface of the fixed shaft and the abutting surface of the thrust plate has the shape of at least a part of the surface of a sphere. A fixing member, made of a metal material, can be fixed around the rotary sleeve and a rotary polygonal mirror and a driving magnet can be fixed to the fixing member.

Abstract: To enable scanning by a light beam with a single unit of rotating optics, a light beam issuing from semiconductor laser 1 is launched into rotating lens mirror 3 through entrance face S.sub.1, thence directed to reflecting face S.sub.2, whereby it is deflected to leave the lens mirror 3 through exit face S.sub.3 and form a spot that scans over the imaging plane.

Abstract: A electrophotographic printing apparatus comprises a first laser source, emitting a first beam in a first direction, and a second laser source, emitting a second beam in a second direction. A roof mirror directs the first beam and the second beam along a third direction, so that the two beams have a substantially coincident virtual source point.

Abstract: A laser beam optical scanning device including a housing, a light source for emitting a unidirectional laser beam, polygonal mirror for deflection scanning a laser beam emitted from the light source within a single plane, and optical members for directing the deflected scanning laser beam on the surface of a photosensitive member through a beam emission aperture of the housing. A transparent member is provided at the beam emission aperture of the housing so as to satisfy the following equation: ##EQU1## where X:distance (mm) from transparent member to surface of photosensitive member,.lambda.:laser beam wavelength (mm),D.sub.0 :beam diameter (mm) at center intensity 1/e.sup.2 on surface of photosensitive member.

Abstract: A method and apparatus for writing bits (or pixels) on a target by scanning a continuous wave laser beam across an array of concave mirrors. The radiation reflected from the concave mirror array images a row of stationary dots on the target during each scan. To write a dot matrix pattern, after each row of dots is written on the target, the target is translated (perpendicularly to the row of dots) by an increment, and another row of dots is then written on the target. The laser beam can be modulated while it is scanned across the concave mirror array, for example, by being selectively transmitted through a shutter. Preferably, the beam is swept across the concave mirror array by reflecting from a rotating mirror (which can be flat or polygonal with multiple facets). In a class of preferred embodiments of the invention, lines of variable length and width (rather than dots) are written on the target. This is accomplished by scanning the continuous wave laser beam across a system of variable lenses.

Abstract: A laser beam printer which includes a laser beam emitting device for emitting a laser beam which has been modulated in accordance with image information; a rotatable deflecting device for rotatably deflecting the laser beam emitted from the beam emitting device; a rotatable photosensitive member which is scanningly exposed to light by the laser beam deflected by the deflecting device; and a control device for controlling the rotation of the deflecting device and that of the photosensitive member. The control device starts the rotation of the deflecting device after starting the rotation of the photosensitive member, so that the deflecting device reaches a predetermined rotational speed simultaneously with completion of pre-rotation of the photosensitive member.