Abstract: In an apparatus for adjusting the intensity of a light beam, a first driving current which is stepwisely increased in a first cycle is supplied to a semiconductor laser. The light beam is deflected to scan a photosensitive drum and is detected to generate a positional signal by a photodetector outside of the drum. The intensity of the light beam is also detected by a monitor detector and compared with a predetermined target intensity. The comparison result is latched in a latch circuit to determine a first drive signal. When the intensity of the light beam reaches the target intensity after the generation of the positional signal, a second drive signal is generated in a second cycle longer than the first cycle instead of the first drive signal and is supplied to the semiconductor laser. The second drive signal is determined in accordance with the comparison result latched in the latch circuit.

Abstract: A photosensor (20a) has a pair of n-type semiconductor layers (21U, 21D) formed on the major surface of a p-type semiconductor substrate (31). A light-shielding pattern (24) comprised of unit light-shielding layers (33) is formed on the major surface of the substrate. When the major surface is scanned by a light beam in the direction (D.sub.X) in which the unit light-shielding layers are aligned, a couple of photo-conversion signals indicating a current position of the light beam on the photosensor are generated in the photosensor. Since the light-shielding pattern is directly provided on the sensor body, no grating glass is required other than the photosensor.

Abstract: A mark reading device that reads marks such as a bar code, or the like on a remote surface. A laser beam is outputted, deflected through a scan angle and the reflected energy is read at a detector. This energy is processed and converted to a usable format for input into a computer, cash register, or any type of data collection device. The present invention improves depth of field and readability by varying the output energy of the laser after each successive scan, thus providing a range of energy levels at the detector.

Abstract: A laser scanner and method for simultaneously generating both a pointer beam and a scan pattern from a single laser source is provided by multiplexing a laser beam between at least one pointer beam path and at least one scanning beam path. Means for multiplexing include refractive and reflective optical components, and electronic means for modifying one or more properties of the laser beam.

Abstract: A double beam scan type optical apparatus for use in a laser printer or the like. Such apparatus comprises two light sources and a lens system which provide scanning means for scanning a surface with parallel output light beams of the two light sources and beam distance controlling means for controlling the distance between the light beams. The reliability of the invention is improved by monitoring the intensity of the beams. Beam intensity checking means provide signals to verify that the intensity of each beam is maintained equal thus assuring that no abnormal conditions exist with the light sources or the lens system of the apparatus.

Abstract: An optical beam scanning apparatus includes a beam-to-beam distance adjuster (300) for rotationally displacing a beam splitter (301). The beam-to-beam distance adjuster (300) comprises three arm members (312, 313, 314) which are linked to each other through notch portions (323, 324). A member (315) is linked to the arm member (313). The beam splitter (301) is secured on the member (315) from which a plate spring (316) extends. A projection member (317) is provided between a leading edge portion of the plate spring (316) and the arm member (314). A rotation angle of the beam splitter (301) can be changed by actuating three arm members (312, 313, 314) in link motion, whereby a beam-to-beam distance between two beams (B.sub.a, B.sub.b) can be also changed.

Abstract: In an optical unit, a light beam is emitted from a light source toward a given object. Part of the light beam is reflected by a reflecting mirror and is returned to a monitor diode which is incorporated in the light source. The reflecting mirror is arranged in an optical path along which the light beam is directed from the light source to the object, but is located outside of an image region containing an optical axis and expanding in the main scanning direction. By use of the light beam returned to the monitor diode, the deflection start position from which the light beam emitted from the light source is deflected is detected. In other words, the deflection start timing is detected. A variation in the monitor current produced by the monitor diode is utilized for controlling the light source, to thereby match the horizontal synchronization.

Abstract: In an optical unit incorporated in a laser beam printer, a laser beam generated by a laser diode is converted by a group of conversion lenses into a laser beam having a predetermined-size cross section. The laser beam is directed toward a photosensitive body by a scanner unit, so as to scan the photosensitive body. A focusing lens allows the rotataing angle of the reflecting faces of the scanner unit to correspond to a desirable point on the surface of the photosensitive body. In other words, the rotating angle is made to correspond to the distance between the optical axis center determined with respect to a main scanning direction and a point to which the laser beam is irradiated for scanning. The conversion lenses include at least one aspheric glass lens. The conversion lenses further includes a pair of plastic lenses which have substantially the same power and opposite polarities with respect to either the main scanning direction or a subscanning direction.

Abstract: A scanning optical apparatus includes a light source, a modulator for intermittently modulating a beam from the light source or for modulating it in amplitude, imaging device for imaging the beam from the light source at predetermined position, a deflector for deflecting the beam from the light source in a predetermined direction, a photoreceptor for receiving the beam deflected by the deflector and modulated by the modulator, processing for processing a signal produced by the photoreceptor, and an adjusting device, responsive to the processing device, for adjusting an imaging position of the beam by the imaging device.

Abstract: A scanning pattern drawing apparatus which scans the surface of a workpiece with a light beam so that a pattern is described on the workpiece with the issued light beam being controlled on the basis of pattern drawing data stored in a pattern memory, wherein the pattern drawing apparatus is able to read many pieces of data in a short period of time even if the frequency of the timing pulses is reduced and which therefore is capable of drawing a precise pattern on a workpiece. A scanning pulse generator produces as scanning pulse in response to a predetermined amount of scanning with the light beam. The scanning pulse is converted to a plurality of resulting timing pulses, and successive parallel outputs of the timing pulses are produced after delaying by a predetermined time. The pattern drawing data is read from the pattern memory in response to the delayed timing pulses.

Abstract: A miniature scan module which is adapted to be installed as part of a terminal or other apparatus for the reading of bar codes has an integrated assembly of a laser diode and a photodetector which is rotatably mounted for reciprocation about an axis of rotation. The assembly is supported in whole or in part on and connected electrically to, a mounting board by flexures which extend between the integrated assembly and supports (posts) on the board. The assembly has a body with a wall and a platform. The wall supports the laser and has a reflective surface which directs light resulting from the scanning of the laser beam across the bar code to the detector. The assembly also carries printed circuits connected to the detector and the laser diode. Connections are made through the flexures to these printed circuits and to other circuits on the mounting board.

Abstract: A radiation image reading apparatus using a storage phosphor plate as a radiation image record is disclosd which includes a light beam scanning device, detection device and control device. The light beam scanning device generates a laser beam and scans the phosphor plate with the laser beam. The detection device detects a phosphor light from the phosphor plate generated by the irradiation of the laser beam and outputs an electrical image signal corresponding to the image information recorded at each of the pixels of the plate. The control device includes an optical shutter which is controlled so that the light beam from the scanning device is provided to generate only one beam spot for each of the pixels of the plate.

Abstract: A scanning optical device having a light source for illuminating an examination object such as eyground of a humaneye, a scanning illumination system for scanning and illuminating the examination object with the light, and a light receiving system for guiding the light reflected from the examination object to a light-receiving section. The scanning optical device also has a synchronous signal generating optical system capable of directly guiding the light from the scanning illumination system to the light-receiving section without the intermediary of the examination object, and a synchronizing signal extraction device for separating a synchronizing signal exactly synchronous with the image signal from the signal derived from the light-receiving section.

Abstract: A divisional exposure apparatus comprises a plurality of exposure devices for dividing the exposure region of a photosensitive element and exposing each divided exposure region by one of the corresponding exposure devices. The exposure signals of the exposure devices are so controlled as to be on the same phase. The scanning directions of the exposure devices are arranged to compensate for the traveling speed of the photosensitive element such that the scanning lines become parallel to the axis of the photosensitive element. The exposure of the region where two adjacent scanning lines connect with each other is controlled to be substantially equal to other exposure regions.

Abstract: A laser beam scanning position detecting device having a beam detecting element for detecting the passage of a laser beam, and determining a print start timing in response to an output signal of the beam detecting element. The print start timing is changed in response to a reference signal or externally derived data.

Abstract: A scanning optical apparatus according to the present invention comprises a light source, a modulator for modulating a light flux emitted from the light source, an image forming device for forming an image of the light flux from the light source to a predetermined position, a deflector for deflecting the light flux from the light source in a predetermined position, a photosensitive device for sensing the light flux deflected by the deflector, an adjusting device for adjusting an image forming position of the light flux by the image forming device in correspondence to a signal obtained by the photosensitive device and an inhibiting device when the light flux emitted from the light source is being modulated by the modulator in correspondence to a predetermined signal. By the scanning optical apparatus of the invention, the focal deviation can be always stably corrected and a stable image with high density can be obtained.

Abstract: An improved flying spot scanner (48, 68) is disclosed, which is particularly applicable to use with a raster output scanner (ROS). The primary scan provided by an ROS is a continuous scan of the optical beam (26) along the scan line (40). The present invention provides a discontinuous pixel-by-pixel scan in the opposite direction to the continuous primary scan. Thus each pixel is positioned statically at its correct location on the photoreceptor (54) during the pixel's duration. At the end of each pixel's duration, the beam snaps rapidly to the position of the next pixel. Use of this invention will form a non-blurred image of each pixel on the photoreceptor (54). The invention uses an optical deflector (50, 70) to drive the beam opposite to the direction of the primary beam scan during each pixel's duration. The optical deflector (50, 70) may be an angle deflector (50) when used in a collimated optical beam (60), or it may be a translation deflector (70) when used in a non-collimated optical beam (72).

Abstract: In a light beam scanning optical system, a toroidal lens and a spherical mirror or a cylindrical mirror function in cooperation to rectify the scanning speed of a light beam deflected at an equiangular velocity by a rotative deflection device to be uniform over the range from the center to both edges of scanning area in the main scanning direction. The toroidal lens is further arranged to maintain each reflective facet of the rotative deflection device and the light collecting surface in the conjugate relation, thereby rectifying an error of image inclination of each reflective facet and at the same time regulating the direction of emission of the light beam so as to lessen the curvature of the field.

Abstract: The characteristics of the component reflecting surfaces of a polygonal-prism mirror are determined by detecting the times of scanning between two given points on each of the component reflecting surfaces. The times for starting the delivery of the output of a video signal for imposition on the scanning lines on the component reflecting surfaces are severally calculated based on the characteristics mentioned above. The video clock is issued with prescribed time cycles based on the times for starting the delivery of output found by the arithmetic operation mentioned above.

Abstract: A horizontal synchronizing signal detecting optical system of an optical scanning apparatus includes a light receiving element for receiving light flux deflected by a deflector and converged by a scanning lens outside an effective scanning range. A prism optical system for reducing the diameter of the light flux which is received by the light receiving element at least within a principal scanning direction is provided.

Abstract: An apparatus is described for generating a light curtain which includes an originally spherical strip-like concave mirror 10 and a light deflecting element 12 arranged in the vicinity of the focal point of the concave mirror. The light deflecting element 12 guides a bundled light beam periodically over the concave mirror 10. The strip-like concave mirror 10 is twisted within itself in such a way that each surface portion of the concave mirror 10 which is illuminated during a complete sweep of the light beam extends at at least substantially the same angle to the beam axis in a plane perpendicular to the scanning direction.

Abstract: The improved compact and inexpensive light beam scanning apparatus capable of scanning with a light beam for image recording or reading in an easy and yet precise manner has a first light source for emitting a scanning light beam that is positioned in the center of the optical unit in the apparatus, as well as a second light source for emitting a light beam to scan an image sync signal generating means for obtaining an image sync signal, which second light source is positioned either ahead of or behind said first light source in a sub-scanning direction. This arrangement obviates the use of heretofore necessary expensive optical elements such as AOM and those for synthesizing or separating light beams, whereby a smaller number of parts need be used than in the prior art. The positions of the respective light sources can be easily adjusted by a light beam adjusting mechanism of a simple design in which the sleeves for retaining these light sources are adapted to be movable relative to each other.

Abstract: An optical scanning system has a deflector for deflecting a beam emitted from a light source portion, a telecentric scanning lens for focusing the deflected beam onto a scanning surface, a beam splitter for splitting a beam reflected by the scanning surface on an optical path between the deflector and the light source portion from an outgoing optical path, and a focus point detector for receiving the beam split by the beam splitter and detecting a focused state of the beam on the scanning surface.

Abstract: A variable density scanning apparatus comprises a semiconductor laser which generates at least one laser beam, a first drive circuit which applies to said semiconductor laser a modulation drive signal having a predetermined modulation frequency in accordance with the density of dots constituting the pattern to be formed on the scanning surface, a dynamic diffraction grating which receives a laser beam from said semiconductor laser and diffracts said laser beam into a plurality of diffraction beams, a second drive circuit which applies to said dynamic diffraction grating a diffraction drive signal having a predetermined high frequency in accordance with the dot density, a polygonal mirror which receives a plurality of diffraction beams from said dynamic diffraction grating and scans said diffraction beam in the main scanning direction, a third drive circuit which applies to said polygonal mirror a rotation drive signal having a predetermined rotation frequency in accordance with the dot density, and a control

Abstract: Images of two fields of view of one or two scenes in a radiation sensor are generated by use of a single detector and common signal process circuitry. The two imaged fields of view, typically a narrow view and a wide view, are provided by two independent telescopes (18, 20), and are combined by use of a field-of-view switch (32) comprising a chopper wheel (34) or an optical switch in synchronized operation with a mirror scanner (22). The same field-of-view switch is employed in performing detector non-uniformity correction functions, such as automatic responsivity control and direct current restoration. Folding optics couples scanned radiation from the scanner to the switch. An additional field of view may be introduced by displacing a folding mirror of the folding optics. Also, a portion of a reflecting surface of the switch may be tilted to admit a reference beam of radiation useful in performing the functions of responsivity control and D.C. restoration.

Abstract: A dual-mode resonant scanning system comprising an electronic control circuit and a dual-mode resonant mechanical scanner to produce an essentially triangular scan pattern. The dual-mode mechanical scanner is mechanically tuned to simultaneously oscillate at a predetermined third harmonic frequency and the free running fundamental thereof. The electronic control circuit drives the mechanical scanner to oscillate at the exact fundamental frequency of the predetermined third harmonic frequency and phase locks the fundamental oscillation to the third harmonic oscillation. The dual-mode resonant mechanical scanner includes an optical scanning element having a first mass, a second mass, at least one torsion rod, a rotational actuator and a mechanical ground designed and integrated together such that the mechanical scanner is self resonant at the predetermined third harmonic frequency and at or within a few hertz of the exact fundamental frequency of the predetermined third harmonic frequency.

Abstract: A device uses fringe laser diode anemometers which, from the beams coming from one or more laser diodes, form measuring volumes having interference fringes. The component of the relative speed of an aircraft in a direction perpendicular to the plane of these fringes is deduced from the modulation of light reflected by particles moving through the measuring volume to cause modulation of the signal of the photodetector of each anemometer during their passage in the measuring volume of this anemometer. By joining two anemometers with the measuring volumes whose planes of the associated fringes are, for example, orthogonal, it is possible to determine two components of the relative speed vector and determine, for example, this relative speed in the longitudinal vertical plane of the aircraft, and to deduce from it the angle of incidence of the aircraft.

Abstract: A beam position sensor for a beam scanner is disclosed for use in a laser printer. The printer comprises three diode lasers each of which emits at a different wavelength. The beams from the three lasers are combined by the use of dichroic plates to form one combined beam. The combined beam is scanned onto a receiving medium by a polygon. The beam position sensor of the present invention is adapted to sense the position of the polygon in order to provide a synchronizing signal which will insure that each raster line in the printer is started at the proper position. The beam position sensor includes a diode laser and optics for projecting a beam from the laser onto the polygon. The beam is reflected back from the polygon into a photodetector which effects the start of a new raster line at the appropriate time.

Abstract: A method and apparatus is provided for line scanning a beam receiving member, wherein a scanning beam is angularly or laterally displaced to compensate for scan line spacing error. The beam is displaced according to error arising from variation (flutter) in the relative motion of the beam and the beam receiving member, or according to error arising from movement of the receiving member while the scanning beam travels to a start of scan position, or both. Embodiments of beam displacement means include a refracting tilt plate, a reflecting tilt plate, a diffracting tilt plate, and a tilt prism.

Abstract: A light source control apparatus comprises light source means for producing first and second beams, a first scan surface to which the first beam is applied, a second surface to which the second beam is applied, scanning means for causing the first and second beams to scan the first and second surfaces, respectively, a fluorescent optical fiber disposed along a scanning direction of the second beam for emitting fluorescent light in response to the second beam incident thereto and transmitting the fluorescent light, and photodetecting means for detecting the fluorescent light. A part of the outer surface of the fluorescent optical fiber can be the second scan surface which has alternately arranged transparent regions and opaque regions, thereby further reducing the number of components of the apparatus.

Abstract: In an image recorder, a recording photobeam and a reference photobeam are periodically deflected by a polygon mirror in a main scanning direction. The recording photobeam is supplied to a photosensitive film while the reference beam is supplied to a transparent grating scale on which a transparent area and an opaque area are formed. The combination boundary of the transparent area and the opaque area has a portion parallel to the main scanning direction. The reference beam transmitted through the transparent area is detected, and the photobeams are deflected in a subscanning direction by an acoustic-optical deflector in response to the detected optical amount of the reference photobeam.

Abstract: A position-detecting system for a moving vehicle wherein the position of the moving vehicle is detected by scanning the light beam emitted from a light beam-emitting means mounted on the moving vehicle in the circumferential direction centering around the moving body, and receiving the light beam reflected from light-reflecting means disposed at at least three positions by means of a light-receiving means mounted on the moving vehicle, comprising a means for detecting the distance between the source of the reflected light received at the light-receiving means and the moving vehicle, and a means for reducing the rotational speed of the light beam scanning means in response to the operation of the distance detecting means.

Abstract: An optical scanner and method in which light beams from a plurality of sources are directed onto a medium to form a composite spot. The relative positions of the beams are detected and changed to change the diameter of the composite spot so that lines formed by such spots appear unbroken. The modulating times, intensities and number of sources of the beams can also be varied to provide a linear relation between the dither matrix and the picture element density.

Abstract: A scanning apparatus for use in a laser beam printer or the like comprising a control means for varying the spacing between adjoining scanning beams of a plurality of laser beams, which further comprises a plurality of light sources, a means for changing intensity, including on/off states, of the beam from the light sources, and a rotating polygonal mirror for allowing the beams to scan the scanned plane in parallel, and is adapted, in accordance with the value of the pixel density of information to be recorded, such that, in the beam scanning direction, the area exposed to the beam is changed by changing the width of a beam intensity modulating pulse, and in the direction perpendicular to the beam scanning, the number of revolutions of the rotating polygonal mirror is changed.

Abstract: A scanning system having a motor-driven scanning element automatically shuts down a scanning laser when the motor is either inoperative or operating below a safe speed. A microprocessor already used to drive the scanning circuitry is also used to control the operation of the motor, including commutation logic, and also controls the automatic laser shut-down. This results in a significant reduction of power requirement.

Abstract: A horizontal sync signal generating device for use with an optical printer to determine the starting positions of horizontal scannings on a photoconductive member for forming images thereon. The generation of horizontal sync timing signals is kept constant regardless of any difference in the characteristics of a light beam transmitted via each scanning face of a polygonal rotary member.

Abstract: An optical scanning apparatus has a semiconductor laser which produces a divergent beam of light. A collimator lens makes the beam of light parallel, a cylindrical lens shapes the beam, and a polygonal deflector deflects the beam through a scanning lens and onto a rotating drum containing an exposure plane. The amount of light reflected back into the semiconductor laser is reduced by forming a slit either inside of the collimator lens or inside of a housing of the cylindrical lens.

Abstract: A dither scanned IR imaging system is disclosed for achieving panoramic coverage. For complete 360.degree. azimuth coverate, the field of view is divided into eight sectors, each imaged by a separate objective lens upon a loose packed 2D photodetector array. The photodetectors are tight packed in the array columns while the columns are loose packed, being on centers spaced by integral numbers of photodetector dimensions (i.e., pixels). The image is dithered the distance between columns over the array by a pair of counter rotating IR refractive discs of wedge shaped cross section. A full-frame partial-sample of the image is taken each time the image advances one pixel until the image has been fully sampled. Tight packed arrays may also be employed if additional means are provided to partially sample the image. In achieving 360.degree.

Abstract: A radiation image read-out apparatus comprises a preliminary read-out device, a final read-out device, an image processor, and a condition adjuster. The condition adjuster comprises an operating device for determining the read-out conditions for the final readout and/or the image processing conditions and feeding the information about them into the final read-out device and/or the image processor. From a first input device, information about a mode selected from among several modes of adjusting the read-out conditions and/or the image processing conditions is fed into the operating device. In cases where a region selecting mode is designated, an image represented by a preliminary read-out image signal is displayed.

Abstract: A very stable deflection system usable with a beam of radiant energy incorporates a self-resonant scanning galvanometer located within an evacuated chamber. The chamber has a hermetic radiant energy transmissive window. An exterior laser source provides a beam of monochromatic light which is directed onto the mirror of the galvanometer. Repetitive deflection of the galvanometer mirror at a predetermined frequency results in the beam being projected onto a target so as to form a very stable and repeatable scanning line. Movement of the target provides a multi-line raster on which an image can be formed.

Abstract: A laser beam recorder arranged to record data with dots of a constant size, constant pitch and constant density, irrespective of possible differences in scanning speed between the middle and peripheral portions of a recording medium. The timing of irradiating the recording medium with the light beam is precipitated and the duration of the irradiation with the light beam is shortened as the scanning speed increases, whereby the dot size and dot pitch can be made constant irrespective of variation in the scanning speed. Further, the light beam is intensified as the scanning speed increases. Though the duration of the irradiation with the light beam is reduced with the increasing scanning speed, the amount of energy for recording one dot is maintained constant by intensifying the light beam as described, whereby the dot density can be maintained constant.

Abstract: A spherical space, especially a hemispherical space, is scanned by an optical scanner for the presence of a target in the scanned spaced. The optical scanner includes an objective lens (4) which scans the space through an optical deflector (1 or 7) arranged upstream of the objective lens and rotatable about two axes, one of which is the optical axis (2, 3) of the objective lens. At least one tiltable prism (5) is arranged downstream of the objective lens (4). At least one row of sensors (6) is arranged downstream of the prism (5) for converting received optical signals into respective electrical signals which are processed under control of a central processing unit (CPU) including a computer and memory (21). Drives (9, 16) controlled by the CPU rotate the deflectors (1 or 7) about the two axes (2, 3) extending perpendicularly to each other. The imaging speed at which an image passes the detector row (6) is always constant independently of the instantaneous viewing or scanning direction.

Abstract: A cylindrical lens for use in a light beam scanning optical system is arranged to have a luminous flux enter a deflection device in straight line in the direction of deflection. The luminous flux deflected by the deflection device enters a toroidal lens and is then directed toward the concave surface of the cylindrical mirror or a spherical mirror to converge on the surface of a photoconductor.

Abstract: A linescan apparatus for detecting salient pattern on a surface of a product comprises: a laser light source for continuously emitting a laser beam; a polygon mirror for reflecting the laser beam; a drive for rotating the polygon mirror to scan said laser beam; an f.theta. lens arranged such that the linescan laser beam strikes against the plane perpendicularly; a carrying device for moving the product in the direction substantially perpendicular to the plane; a mirror for reflecting the linescan laser beam reflected at a surface of the product to direct the linescan laser beam to the polygon mirror through the f.theta. lens, the mirror being positioned apart from the second plane; and a beam position detector for detecting unidimensional position of a spot mede by the linescan laser beam projected thereon from the mirror via the polygon mirror. This linescan apparatus provides three-dimensional data of a surface of the product.

Abstract: A beam position sensor for a beam scanner is disclosed for use in a laser printer. The printer comprises three diode lasers each of which emits at a different wavelength. The beams from the three lasers are combined by the use of dichroic plates to form one combined beam. The combined beam is scanned onto a receiving medium by a polygon. The beam position sensor of the present invention is adapted to sense the position of the polygon in order to provide a synchronizing signal which will insure that each raster line in the printer is started at the proper position. The beam position sensor includes a diode laser and optics for projecting a beam from the laser onto the polygon. The beam is reflected back from the polygon into a photodetector which effects the start of a new raster line at the appropriate time. In order to minimize the number of optical elements in the beam position sensor and to simplify the device, the diode laser and the photodetector are located along the same optical axis.

Abstract: This is an electronic scheme for correcting mechanical misalignment and electrical delays from laser beam to laser beam in the scan direction of a multiple beam laser scanning system for use in an electrophotographic machine. The position at which a reference beam is turned on is sensed and adjusted to a desired position. Thereafter, the positions at which non-reference laser beams are turned on are sensed and adjusted to the desired position. In one enbodiment, the energization of laser beams is positioned at the trailing edge of the second element of a photodector. In a second embodiment, the point of full laser energy is matched, beam to beam, at the junction of the same two elements in a CCD array. Programmable delay lines are used to obtain sub-pel resolution.

Abstract: Scanning and synchronizing light beams are deflected by a light deflector. The scanning light beam is used to scan an object surface, whereas the synchronizing light beam is applied to a grid for generating a synchronizing signal to detect the scanning position of the scanning light beam on the object surface. The grid includes a starting point control area, corresponding to a main scanning cycle starting position on the object surface, for modulating the synchronizing light beam applied to the grid so that light having passed through the starting point control area will have a different phase than the light from the other portion of the grid.

Abstract: An optical scanner for a laser printer or the like, capable of forming dots on scanning lines which are apparently the same in length. When the respective scanning speeds of spots of laser beams reflected respectively by a plurality of reflecting surfaces of a polygonal rotating mirror are different from each other, correction clock pulses are inserted in a print control clock signal for each scanning line.

Abstract: Rays of light emitted from a light source are converged into a light beam by a converging optical system. The converged light beam is focused in one direction by a first focusing optical system into a linear image having a longitudinal direction corresponding to a main scanning direction in a light beam scanning device. A light deflector for deflecting the light beam has a deflecting surface disposed near a point where the linear image is focused by the first focusing optical system. The deflected light beam is focused as a light spot on a scanned surface by a light beam scanning lens serving as a second focusing optical system. The focused light spot scans a surface at a substantially constant speed. the light beam scanning lens comprises a single-element lens having a cylindrical surface facing the light deflector and a toric surface facing the surface which is scanned by the focussed light spot.

Abstract: A beam recorder comprises a beam generator, a deflector for deflecting the beam to scan the beam, and a light intensity control unit for controlling a light intensity of the beam. The deflection has a plurality of deflection planes to which the beam is directed, and at least one of the deflection planes in a non-scan plane. The light intensity control is effected by utilizing a period in which the beam is directed to the non-scan plane.