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 method and apparatus for delivering laser energy to an object, by: energizing at least one laser energy source having a plurality of at least two spaced, active segments to emit a laser beam from each segment, and to thereby output from the laser energy source a plurality of separate laser beams along respective optical axes initially spaced from each other according to the spacing of the active segments, which beams tend to diverge and thereby to overlap as they progress along their respective optical axes; and at a near-field region of the at least one laser energy source or a region optically conjugative with the near-field region, where the beams are still separated and spaced from each other, laterally displacing the optical axis of at least one of the beams with respect to that of the other before delivering the plurality of beams to the object.

Abstract: A printer system for producing color prints includes: (a) three light sources, each generating a light beam of different wavelengths; (b) three modulators, each of the modulators modulating intensity of each of the light beams by image data, to provide three modulated light beams; (c) a beam combiner combining the three modulated light beams into a single light beam; (d) a single set of beam shaping optics shaping this single light beam into a shaped light beam having different vergences and waist locations in the page and line directions, the vergences and the waist locations being substantially the same in each of the three wavelengths; (e) a light deflector deflecting the shaped light beam to provide a deflected beam, and performing a scanning function; (f) an f-.theta. lens focusing the deflected light beam onto an associated image surface.

Abstract: An optical pickup apparatus including a polarization plane rotary unit arranged between a semiconductor laser and an objective lens, and a polarizing film arranged between the polarization plane rotary unit and the objective lens. The polarization plane rotary unit includes liquid crystal, two glass plates sandwiching the liquid crystal, and transparent electrodes patterned to a predetermined configuration on an inner face of these glass planes. The polarization plane rotary unit permits passage of the laser beam without rotating the plane of polarization of the entire laser beam at the time of recording, and permits passage of the laser beam with the plane of polarization of the center portion of the laser beam rotated and the plane of polarization of the remaining outer portion of the laser beam not rotated at the time of reproduction. Only the outer portion of the laser beam is focused on a magneto-optical disk in a reproduction mode, so that a main beam of a small spot is formed by mutual interference.

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: Disclosed is a laser print head, suitable for use with a recording medium, comprising a print head base comprising a plurality of mounting surfaces, one or more optical radiation source removably affixed to a first base mounting surface, at least one collimating lens, at least one focusing lens affixed to a second base mounting surface, a pre-objective lens affixed to a third base mounting surface; an objective lens, and one or more optional mirror facets.

Abstract: A bouncing ball scanner is described which is a ball driven in a reciprocal motion for reflecting image-bearing light onto a photosensitive medium. The image-bearing light can be dictated by a computer, in which case the photosensitive medium may be film for a printed output, or the image-bearing light may be reflected from a subject having an image imprinted thereon, and the photosensitive medium may be a charge coupled device where the image is being read into a computer. The bouncing ball scanner comprises a ball being driven in a reciprocal motion by electromagnetic forces acting thereon. The motion of the bouncing ball is substantially linear in each direction so as to allow ease of calculation of ball position thereby ease of knowledge of pixel position on the photosensitive medium.

Abstract: An image forming device wherein a Gaussian laser beam is scanned imagewise on a photosensitive recording medium by an image forming optical system including an optical filter having such a laser beam filtering pattern that the optical transmittance is a minimum value M of 40-60% at the center thereof and gradually increases from the center in the radially outward direction in a Gaussian distribution mode. The filter has a filtering radius R.sub.f which is a distance between the center and a point on the filter providing a transmittance equal to 100-(100-M)/e.sup.2 % and which is not smaller than 0.9 R.sub.b but not greater than 1.1 R.sub.b where R.sub.b is a beam radius of the Gaussian laser beam.

Abstract: A laser beam scanning apparatus and method for providing controllable print density. The laser beam scanning apparatus includes a modulator for modulating a light beam, a rotating polygon mirror for deflectively scanning a light beam which is passed through the modulator, at least one lens unit having at least one lens which is movable to a position on the optical axis and a position completely off the optical axis, and a controller for switching the modulating clock frequency of the modulator and the rotating speed of the polygon mirror together with selective shifting of the at least one lens unit or lens thereof to a position on the optical axis or completely off the optical axis whereby the method effects control of the apparatus for controlling print density.

Abstract: Pumped laser crystals for use in an imaging apparatus are designed and housed so as to minimize variation in dot size across the spectrum of duty cycles ranging generally from 1% to 100%--that is, from print densities ranging from every hundredth pixel to every consecutive pixel.

Abstract: A method of producing an image on a printing medium comprises producing a pulse train of modelocked laser pulses, providing a source of image input data in the form of a series of gate pulse of varible length and modulating the pulse train with reference to the gate pulses to produce a gated pulse train for producing the image on the printing medium. An apparatus for carrying out the method is also provided.

Abstract: An optical probe element for focusing light from a light source into micro light of a diameter not larger than the diffraction limit, includes a light transmitting flat substrate and an optical probe formed on one of the surfaces of the flat substrate. The optical probe has a substantially conical light transmitting projection, and a reflective film which covers the conical surface of the projection so that the tip of the projection is exposed. The optical probe element enables the optical probe to be formed on the flat substrate using a semiconductor processing technique, thereby achieving efficient mass production of a standardized optical probe element. Thus, a recording and reproduction apparatus using the optical probe element is efficiently mass-produced.

Abstract: A light beam optical system is provided according to the present invention for focusing light beams from a light source on the surface of a photoconductive drum and the like via an optical system. This light beam optical system is capable of adjusting focal dislocation with high precision without being influenced by adhesion of toner for forming an image and the like to the photoconductive drum and the like or by change in the position of a light receiving section generated due to temperature change and the like. The light beam optical system comprises an optical system for focusing light beams from a light source on a photoconductive drum, a light receiving section for detecting on which of the front side or the rear side of the photoconductive drum light beams are focused, and control device for controlling the optical system based upon the detected result so that light beams are focused on the photoconductive drum.

Abstract: A light source is disclosed for use an optical printer illuminating a spatial light modulator to efficiently and uniformly project light onto a photosensitive medium while providing a simpler design of the spatial light modulator in the optical printer. The light source uses light emitting diodes opposed across a light pipe. The light from the light emitting diodes propagates in the light pipe until striking a redirection structure which redirects the light out of lateral surface of the light pipe.

Abstract: The present invention allows output of image data without change when input image data and image data to be outputted have different resolutions and also allows reduction in a processing time and improvement in operating efficiency by providing an image recording apparatus. Some of lenses which form a telecentric lens system (optical system) are provided such that positions thereof in a direction along an optical axis can be varied by drive of a pulse motor 10. Due to the movement of these lenses, an imaging spot diameter on a photosensitive material is varied. The spot diameter is varied based on a resolution of the input image data. When the resolution of the input image data is lower than a previously set resolution, with the volume of the image data being left unchanged and the imaging spot diameter being increased, the previously set resolution is varied and recorded.

Abstract: A printing apparatus having a fixed focal point for a recording medium to which the printing apparatus writes, the apparatus comprises a rotor; an intensity-modulated light source adapted to emit a light beam along an optical path; a platform having three variably positioned ball feet to which platform the light source is fixed for maintaining the positional relationship of the light source in relation to the focal point; a plate having three grooves attached to the printing apparatus which cooperatively receives the ball feet; and a housing that receives the plate and platform and cooperatively attaches to the rotatable rotor to move the light source for scanning the light beam along the recording medium, for permitting removal and replacement of the light source in a precise fashion.

Abstract: A laser printer of the type having predeflector components and postdeflector components is assembled by aligning the predeflector components on a bar and aligning the bar with a printer frame assembly having the postdeflector components in an alignment fixture. After the bar and printer frame have been aligned in the fixture, they are mechanically attached using flexures between the bar and the printer frame such that the bar and printer frame are constrained from moving relative to each other. Finally, the assembled components are removed from the alignment fixture.

Abstract: The disclosure of the current invention describes a compact optical system for and method of forming an image on an intermediate image-forming surface such as a photoreceptor drum at a high speed. An image-forming light source such as a laser light source is placed between an image-focusing element such as a focusing mirror and an image-scanning unit such as a polygon mirror. According to one preferred embodiment, the image-forming light source is placed in a scanning area defined by a predetermined scanning angle of the image scanning unit.

Abstract: A color image forming device that can certainly correct uniform velocity error associated with the characteristic of each optical system and can realize high-quality color image printing by performing a fine laser beam irradiating position control, in consideration of an error in surface accuracy of each mirror surface of a rotary polygon mirror. The color image forming device includes a storage unit for holding uniform velocity correction data previously created for each mirror surface of a rotary polygon mirror to correct a distortion in expansion or contraction of the electrostatic latent image in the main scanning direction due to the characteristic of an optical system, and an image clock generating unit for reading uniform velocity correction data on each mirror surface used in the rotary polygon mirror at a scanning time out of the storage unit and then generating image clock pulses for image signal creation with a period corresponding to the uniform velocity correction data.

Abstract: An optical recording and data processing system for exposing an image on to a flexible, light sensitive medium, which includes a medium holder having an inner cylindrical wall portion against which is held said medium, and a light source having an approximately rectangular emitting aperture, with a short aperture axis and a long aperture axis, operative to emit a beam of light having a rectangular cross section with a long axis corresponding to the long aperture axis and a short axis corresponding to the short aperture axis. An optical modulator is aligned with the light source so as to intercept light from the beam of light and produce a spatial modulation pattern across the long axis of the beam of light. A pattern shifter for shifting the spatial modulation pattern across the length of the long axis at a constant rate is provided as is a pattern rotator for rotating the spatial modulation pattern at a rate equal to the rate of shifting of the spatial modulation pattern.

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 photoprinter is described, including a print head comprising parallel substrates. The bottom substrate supports an array of microtips that rest on cathode columns. Gate lines, orthogonally disposed relative to the cathode columns are located at the top level of the microtips and have openings through which the microtips can emit electrons, due to field emission, which bombard a nearby conductive phosphor layer, thereby emitting light. A bundle of transparent fibers, cast in a suitable medium, are permanently and transparently attached to the upper surface of the top substrate and are in one to one alignment with the microtips. The far side of the fiber bundle may be ground and polished to fit the contours of a rotatable photosensitive drum. A method for manufacturing the print head is also provided.

Abstract: An optical printer capable of being decreased in the number of parts, small-sized and weight. A plurality of color filters are selectively alternated or changed with each other with respect to a common luminous section and such changing-over among the filters is carried out using a transfer unit for a print head, resulting in only one set of the luminous section and optical system being required. Also, power required for alternating or changing the filters with each other Is obtained by the transfer unit for the print head without arranging any specific unit.

Abstract: A Mid-Objective scanner system for correcting astigmatism, bow distortion and field curvature including a tilted lens or a toric lens for producing an opposite amount of astigmatism to correct astigmatism, a scanning mechanism and a concave cylindrical mirror for directing the scanned beam onto to a workpiece wherein the concave cylindrical mirror has a radius of curvature that corrects the field of curvature in the image plane of the workpiece and thereby enables the scanner system to correct astigmatism, bow distortion and field curvature.

Abstract: A device for producing a screen printing stencil has a light source for emitting a bundle of light whose focus lies in the region of a light-sensitive layer present on a stencil screen. Furthermore, there is an apparatus for generating a relative movement between the bundle of light being incident on the light-sensitive layer in accordance with a desired stencil pattern. The bundle of light is linearly polarized in at least one section. An electro-optical modulator for rotating the plane of oscillation of the bundle of light is arranged in this section. The electro-optical modulator rotates the plane of oscillation of the bundle of light in accordance with received stencil pattern data. An analyzer is positioned in the light path downstream of the electron optical modulator. The analyzer passes the bundle of light having a plane of oscillation at one orientation and blocks the bundle of light having a plane of oscillation at an opposite orientation.

Abstract: Laser guiding and focusing apparatus for imaging lithographic printing members responsive to the output of laser devices. Radiation passes through at least one discrete layer of a printing member and ablates one or more underlying layers, resulting in an imagewise pattern of features on the printing member. The radiation is obtained from a laser diode and its dispersion reduced to produce an image spot with maximum depth-of-focus tolerance.

Abstract: A multi-beam optical system includes: a light beam generating part for generating a plurality of light beams using a plurality of light-emitting parts which are offset from each other in the sub-scanning direction and which are individually controllable; a coupling optical part for transmitting said plurality of light beams generated by said light beam generating part; an aperture part for defining said plurality of light beams, respectively; a beam combiner part for combining said plurality of light beams; a first image forming part for forming images of said plurality of light beams passing through said coupling optical part; a deflector part for deflecting said plurality of light beams output from said first image forming part, the images of said plurality of light beams being formed in a vicinity of said deflector part; and a second image forming part for forming images of said plurality of light beams deflected by said deflector part, wherein an exit pupil is in a conjugated arrangement with said second

Abstract: A print head for use in a printer has a light source, a pair of lenses, and a pair of light guides. The light source has five light-emitting diodes for emitting light through respective optical fibers of the light guide to the lens. The optical fibers have the same curvature and length for uniformizing the amounts of light that are applied through the lens to a photosensitive medium.

Abstract: There is provided an optical filtering system intended for use in a raster scanning arrangement for a document processing system. The document processing system includes a laser beam generating device providing a laser beam and a raster scanning device for transmitting the provided laser beam along a path. The optical filtering system includes a) an optical filter, disposed in the path, for reflecting the laser beam or permitting a portion of the laser beam to be transmitted therethrough, and b) a heating subsystem, thermally communicating with the optical filter, for maintaining the optical filter at a substantially fixed temperature.

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: A method for correcting astigmatism, bow distortion and field curvature using a Mid-Objective scanner system wherein the system includes a tilted lens or a toric lens for producing an opposite amount of astigmatism to correct astigmatism, a scanning mechanism and a concave cylindrical mirror for directing the scanned beam onto to a workpiece wherein the concave cylindrical mirror has a radius of curvature that corrects the field of curvature in the image plane of the workpiece and thereby enables the scanner system to correct astigmatism, bow distortion and field curvature.

Abstract: A raster output scanner (ROS) with a liquid crystal window located at the output of the ROS for correcting the nonuniformity of a light beam generated by the ROS is disclosed. Since the photocells in the liquid crystal can be controlled individually, a variable attenuation to match the curve of the intensity of the light beam, generated by the ROS, can be applied to the light beam. When the light beam with a variable intensity passes through the liquid crystal window of this invention, each cell applies an attenuation to offset the variation in intensity of the light received by that cell. Therefore, the light beam emerging from the liquid crystal window will have a uniform intensity regardless of the variation of the intensity generated by the ROS.

Abstract: Fluorescent reference tracks for use in correcting for geometric and other distortions in an image scanning system comprising a rotatable cylindrical drum assembly and an optical subsystem disposed within a protective housing is disclosed. Fluorescent reference tracks illuminable by light outside the visible spectrum, such as ultraviolet (UV) light, are disposed on inner surfaces of inwardly directed film support shoulders of the drum assembly. Respective edges of film containing an image to be scanned are retained on the outer surfaces of the film support shoulders of the drum assembly. As the film is rotated by the drum assembly past a primary light source disposed adjacent one side of the drum, light from the primary light source is directed through the film and is focused by a lens assembly disposed internal to the drum assembly onto a sensor assembly disposed at an opposite side of the drum assembly, which scans the transilluminated film portion.

Abstract: A digital printer for printing images in response to full-frame, two-dimensional digital image data input from an outside source. The digital printer is a novel combination of a two dimensional backlight for producing full frame illumination in a single flash, a photoreceptor sensitive to light emanating from the backlight, a two-dimensional, transmissive light valve, an imaging system, and a driver. The light valve is disposed between the backlight and the photoreceptor so that light from the backlight is transmitted through the light valve, producing a full-frame, two dimensional image on the photoreceptor in response to a single flash of the backlight. The full-frame, two dimensional image corresponds to a pattern formed on the light valve in response to the full-frame, two dimensional digital image data. The imaging system is disposed between the light valve and the photoreceptor, such that it focuses the full-frame, two dimensional image onto the photoreceptor.

Abstract: Compact raster scanner assemblies, and systems which use such assemblies, having a laser source generating laser light; a photoreceptor moving in a process direction; and a raster scanner raster sweeping the photoreceptor. The raster scanner includes a rotating polygon, an F-.theta. scan lens in the sweep plane, and a first folding mirror positioned along a first axis for reflecting laser light passing through the F-.theta. scan lens toward the photoreceptor. The first folding mirror being aligned along an axis which is at an angle with both the process direction and the resulting fast scan direction. The raster scanner assembly further including a second folding mirror for receiving laser light reflected by the first folding mirror and for directing that laser light toward the photoreceptor such that the laser light sweeps across the photoreceptor in a direction perpendicular to the process direction.

Abstract: An illumination device for illuminating a surface to be illuminated, includes a light source and an irradiation optical system for mixedly projecting light beams from the light source to the surface, wherein the irradiation optical system has a first focal point with respect to a first plane, which is disposed at a position out of the surface.

Abstract: The present invention provides a method and a device for color laser marking for attaining visible coloring without drastic modification of conventional devices and without using dyestuffs. To this end, in a color laser marking method, a workpiece (10) is a synthetic material made from organic and inorganic materials and, when irradiating laser light, patterns in different colors can be obtained by varying the received light intensity on the workpiece (10). In addition, in a color laser marking device, when the workpiece (10) is a synthetic material made from organic and inorganic materials, a controller (11) outputs laser irradiation intensity varying signals to at least one of laser irradiation intensity varying means, such as a laser oscillator (1).

Abstract: An optical arrangement for an optical scanning apparatus which can record a plurality of high precision information concurrently, provides for a laser beam emitted from a single light source to be polarized in two polarization directions, and each of the two polarized beams is further imparted with different information according to its polarization direction. Then, the two polarized beams are used for scanning over a photosensitive member to concurrently record respective information at different positions on the photosensitive member. In order to suppress induced light fluctuation depending on an incident angle of light on the beam splitter, an optical rotation means is provided in the optical system, such that a desired optical rotation control can be obtained corresponding to the incident angle on the beam splitter, so as to compensate for the fluctuation of light whereby the beam splitter can be arranged to be free of the influence of the incidence angle of the beam.

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 scanning optical system including a light deflector rotating about a rotational axis perpendicular to a main scanning direction, a laser beam emitter for emitting a laser beam which scans a scanning surface along the main scanning direction and for making the laser beam incident upon the light deflector with a first angle with respect to a sub-scanning direction perpendicular to the main scanning direction, a curved mirror having a curvature at least along the main scanning direction for reflecting a laser beam deflected by the light deflector with a second angle with respect to an incident laser beam upon the curved mirror, and an anamorphic lens disposed between the curved mirror and the scanning surface. The anamorphic lens has a first surface having a first aspherical surface along the main scanning direction, and a second surface having a second aspherical surface which is not rotationally symmetrical about an optical axis of the anamorphic lens.

Abstract: An optical probe element for focusing light from a light source into micro light of a diameter not larger than the diffraction limit, includes a light transmitting flat substrate and an optical probe formed on one of the surfaces of the flat substrate. The optical probe has a substantially conical light transmitting projection, and a reflective film which covers the conical surface of the projection so that the tip of the projection is exposed. The optical probe element enables the optical probe to be formed on the flat substrate using a semiconductor processing technique, thereby achieving efficient mass production of a standardized optical probe element. Thus, a recording and reproduction apparatus using the optical probe element is efficiently mass-produced.

Abstract: An optical probe element for focusing light from a light source into micro light of a diameter not larger than the diffraction limit, includes a light transmitting flat substrate and an optical probe formed on one of the surfaces of the flat substrate. The optical probe has a substantially conical light transmitting projection, and a reflective film which covers the conical surface of the projection so that the tip of the projection is exposed. The optical probe element enables the optical probe to be formed on the flat substrate using a semiconductor processing technique, thereby achieving efficient mass production of a standardized optical probe element. Thus, a recording and reproduction apparatus using the optical probe element is efficiently mass-produced.

Abstract: A laser light radiation device has a light source for emitting laser light which is modulated according to an image signal, a collimator lens for collimating the laser light emitted from the light source, and a polygonal mirror for deflecting the laser beam emerging from the collimator lens. The device further has a diffraction grating in a laser optical path between the collimator lens and the polygonal mirror.

Abstract: A raster scanning optical system and method for adjusting a scan line location on a light receiving member by a desired amount. A photoreceptor receives a light beam as the photoreceptor is advancing in a slow scan direction. A polygon mirror scans the light beam across the photoreceptor at a scan line location extending in a fast scan direction. A light transmissive plate is located in the path of the light beam between the polygon mirror and the photoreceptor. The light transmissive plate is adjusted by an adjusting device to displace the scan line location on the photoreceptor by the desired amount in a direction parallel to the slow scan direction.

Abstract: In the electrophotographic image recording apparatus, the optical path switching mechanism switches the optical path between an image reading mode and an image recording mode. In the image reading mode, the optical path switching mechanism directs light from a light scanning portion toward the original. Light reflected from the original is guided by a light guiding mechanism to a light receiving element where the light is converted into electrical signals.

Abstract: In the production of a screen printing stencil, a thin-walled hollow cylinder having a light responsive layer on the outside is rotated about its cylinder axis and exposed by means of a laser beam impinging on it. The laser beam is focused in the region of the light responsive layer. The laser beam is moved in the direction of the cylinder axis, and is switched on and off in agreement with a desired stencil pattern. A radial deviation of the actual position of the wall of the hollow cylinder from its ideal position is determined from at least one measuring position fixed relative to the laser beam for a multiplicity of circumferential positions of the hollow cylinder. A first actuating signal is then derived from at least one of the radial positional deviations obtained at the measuring positions.

Abstract: An image reading apparatus high in illumination efficiency which can illuminate an image reading position by use of at least one polarizing element is disclosed. The image reading apparatus can illuminate an object to be image read sufficiently, even if the object is floated away from a predetermined image reading position. In the image reading apparatus, the major illumination light L2 from an illumination unit 1 and the light L2 reflected from the object and then introduced onto light-electricity transducing elements are located on substantially the same plane, and further the polarizing elements 2 and 3 are interposed between the illumination unit 1 and the object 20 and between the object 20 and the light-electricity transducing elements 7, respectively.

Abstract: A laser marking apparatus, capable of marking at a high scanning speed, effectively utilizing a laser power, and providing high marking accuracy, irradiates an incident laser beam from a laser beam source onto a marking surface by raster-scanning through a raster scanning system. The raster scanning system includes an X-direction polarizing mirror, a Y-direction polarizing mirror, a field lens, and a mask. A double polarizing prism, which includes a pair of polarizing prisms (13a, 13b) for branching the incident laser beam (1) into twin laser beams, is arranged in series at an intermediate position between the laser beam source (2) and the upstream one of the X-direction polarizing mirror (3) and the Y-direction polarizing mirror (8).

Abstract: A method of imaging a fine pattern having a group of lines extending along orthogonal first and second directions and a group of lines extending along a third direction different from the first and second directions includes illuminating the pattern obliquely, to form an image of the line pattern. Illumination beams along the first, second and third directions, respectively, each has an intensity sufficiently lowered as compared with that of a particular illumination beam along a particular direction different from the first, second and third directions.

Abstract: An image forming apparatus for forming images by allowing a light beam to be scanned and exposed on a photosensitive body includes a single detecting device for detecting the light beam scanned and exposed onto the photosensitive body, a plurality of signal generating devices for generating a predetermined control signal on the basis of an output from the detecting device, and an output control device for controlling the routing of an optical signal output which is output from the detecting device to the objective signal generating device.