Abstract: In a scanner unit for An overhead image scanner, a rotatably mounted mirror reflects light from a surface to be scanned off to a focusing lens to form an optical image of a scanned line on a linear image sensor. An extension arm is connected to the minor for rotation therewith. To one end of the arm is attached an electromagnetic drive system and to the other end a light reflecting member which is formed with a multiplicity of microscopically spaced apart tracks running parallel to the length of the extension arm. A laser beam spot is formed on the reflecting member and a photodiode array detects reflections therefrom to produce a plurality of output signals representative of the amounts of reflections incident on different areas of the array.

Abstract: In an optical scanning device, a redirecting flat mirror is provided that redirects a laser flux from a laser source to a polygonal mirror. In order to reduce the size of the optical scanning device in the direction in which the optical elements are generally aligned, the flat mirror is placed between the polygonal mirror and a curved surface mirror. Preferably, the polygonal mirror is arranged between the curved surface mirror and an anamorphic lens to further reduce the size. Further, the laser source may be placed between the curved surface mirror and the anamorphic lens.

Abstract: An image scanning apparatus can obtain, using a simple optical detection system, original sheet information including size and displacement information of an original sheet before an image scanning operation starts. The image scanning apparatus comprises a single beam emitting unit for emitting a coherent first beam. A deflecting unit deflects the first beam so that the first beam traces a predetermined scan line on a plane including a surface of the original sheet. A second beam is generated by reflection of the first beam at the surface of the original, and the second beam is input to the sensing unit via the deflecting unit. The original sheet information is obtained in accordance with the detection of a sharp change in the intensity of the second beam received by the sensing unit with reference to the scanning position of the first beam.

Abstract: In a scanning optical system, a light emitting device emits a beam to a deflection mirror. The beam is inclined in the direction of the auxiliary scanning, so that the optical axis of the beam incident to the deflection mirror intersects the rotational axis of the deflection mirror. The optical axis of the beam, when the beam reaches the center of a predetermined scanning angle zone, is orthogonal to a light reflection surface of the deflection mirror when seen from the auxiliary scanning direction. The deflected beam is reflected by a curved mirror and directed to an object surface through an anamorphic lens. The optical axis of the anamorphic lens is displaced with respect to the optical axis of the scanning optical system.

Abstract: In a light scanning system, a semiconductor laser outputs a laser beam which diverges with a beam divergence angle. A condensing/scanning optical system condenses the laser beam and causes the laser beam to scan a predetermined surface-to-be-scanned. The distance between the beam waist of the laser beam and the surface-to-be-scanned as measured in the direction of the optical axis of the condensing/scanning optical system is set larger as the beam divergence angle of the laser beam as emitted from the semiconductor laser increases so that the beam diameter of the laser beam on the surface-to-be-scanned is constant irrespective of the beam divergence angle of the laser beam as emitted from the semiconductor laser.

Abstract: A light collection device for use in a film image digitizing apparatus comprises a housing having an elongated aperture extending along a light beam scan line. The aperture receives light transmitted through a sheet of film from a light source. A diffusing member, disposed within the aperture and extending along the scan line, optically diffuses the light received by the aperture. The housing may include one or more reflective interior surfaces. A linear array of photodiodes, disposed within the housing and extending along the scan line, detects the light diffused by the diffusing member. Each of the photodiodes generates an analog signal representing an intensity of the detected light for each of a plurality of pixels. A summing circuit, coupled to each of the photodiodes, sums the analog signals generated by the photodiodes for each of the pixels to produce an output analog signal representing an overall intensity of the light transmitted through the sheet of film for each of the pixels.

Abstract: In an optical beam scanning apparatus having an electrooptic lens, a focal point of a light beam is adjusted to be exactly positioned on a scanning surface by a feedback control at any positions scanned by the light beam during a single scanning period. A deviation of a focal position of the light beam relative to the scanning surface is detected, and a detection signal corresponding to the deviation of the focal position is output. A focusing signal is stored and supplied which corresponds to the detection signal obtained when a focal position of the light beam is exactly positioned on the scanning surface. A differential signal is obtained as a difference between the focusing signal and the detection signal. A level of a driving voltage to be supplied to the electrooptic lens is controlled by a driving voltage controlling signal which is a sum of the differential signal and the focusing signal.

Abstract: The improved scanning optical system comprises a gas laser 10 for generating writing beam, a semiconductor laser 50 for generating monitoring beam of a different wavelength than the writing beam, a polygonal mirror 20 for deflecting and scanning the rays of light from each of the sources, a scanning lens 30 with which the rays of light deflected by the polygonal mirror 20 are focused on an image plane 40, a dichroic mirror 60 provided between the scanning lens 30 and the image plane 40 to isolate the monitoring beam from the optical path of the writing beam, and a signal generator A that receives the isolated monitoring light to generate a monitor signal. This optical system will not lower the energy of the writing beam, will not experience any change in the quantity of the monitoring beam due to leakage, and is free from the problem of curvature in the scanning lines of the monitoring beam.

Abstract: A polygonal mirror is rotated by a brush motor, and a laser beam deflected by the polygonal mirror is detected by a sensor for generating a signal which determines a printing start position of each scanning line. The rotating speed of the motor is proportional to the frequency of the signal, and when the frequency of the signal becomes equal to a reference value, the motor can be judged to come to a steady rotation state. In a control circuit, the rotating speed of the motor is detected from the frequency of the signal, and the difference between the detected speed and a reference value is calculated and is sent to a comparator. Based on the speed difference and the back electromotive force which occurs in the motor, the comparator controls the driving voltage of the motor.

Abstract: An underwater viewing system includes a dry and wet end. Illumination energy is provided to the wet end where it is scanned and the resulting scanned illumination is directed to a scene of interest. Energy reflected from the scene is received by the wet end where it retraces the path of illumination to the dry end. The received energy is directed to a detector and ultimately to a video processor. The wet end may be disposed in a remote piloted vehicle with optical waveguide payed out from the dry end to supply the illumination and to conduct the received energy. Communication information may be transferred between the dry and wet end may be over the same path followed by the illumination energy but at a different frequency. The illumination and communication energy may be separated based on their frequency. A polarization device may be provided for maximizing the amount of received energy that is provided to the detector.

Abstract: In an optical scanning apparatus, there are arranged a light source, a first optical system for converting a light beam emitted from the light source to a convergent light beam, a deflector for deflecting the convergent light beam from the first optical system, and a second optical system for image-forming the convergent light beam deflected by the deflector as a spot on a surface to be scanned. The symmetrical axis of the second optical system with respect to a main-scanning direction is disposed so as to have an inclination relative to a normal to the scanned surface in a main-scan cross section. As a result, aberrations of the optical scanning apparatus, especially degradation of f.theta. characteristics due to backward and forward movement of a mirror surface caused by the rotation of the polygon mirror, which occur in an optical scanning system wherein a convergent, light beam is caused to enter the polygon mirror, are reduced.

Abstract: Optical scanner having a laser source for generating a laser beam, a first deflector for deflecting the laser beam towards an array of reflectors, the first deflector and the array of reflectors being rotatable relative to each other about a first axis, drive means for providing a rotation, and at least one detector for detecting backscattered light, said first deflector and said array of reflectors being arranged to deflect said laser beam in a direction substantially parallel to the first axis.

Abstract: A moving mask is incorporated in a flying spot scanner to reduce flare. The mask obscures all portions of the object being scanned, except for a small region surrounding the point currently being scanned. The mask moves to maintain registration with the flying spot. A rotating slotted disk with curved slots in cooperation with a fixed mask having a slot is described as one mechanism for achieving such masking.

Abstract: An optical scanning device for scanning a tape-like record carrier. The device includes an optical system for focusing a radiation beam at the record carrier, which radiation beam causes a scanning spot to occur on the record carrier. The device also includes a rotary polygon mirror which causes the scanning spot to be displaced transversely to the direction of the tape with a specific repetition rate. The tape-like record carrier is moved with a certain velocity in the longitudinal direction of the tape relative to the scanning device. In this manner, the record carrier is scanned in accordance with a track pattern formed by a longitudinal path of substantially parallel tracks which have a substantially constant track pitch and a track direction transverse to the longitudinal direction of the record carrier. During operation, vibrations occur which cause displacements to occur of the scanning spot over the recording layer transverse to the scanning direction.

Abstract: In an optical beam scanning apparatus having an electrooptic lens, a focal point of a light beam is adjusted to be exactly positioned on a scanning surface by a feedback control at any positions scanned by the light beam during a single scanning period. A deviation of a focal position of the light beam relative to the scanning surface is detected, and a detection signal corresponding to the deviation of the focal position is output. A focusing signal is stored and supplied which corresponds to the detection signal obtained when a focal position of the light beam is exactly positioned on the scanning surface. A differential signal is obtained as a difference between the focusing signal and the detection signal. A level of a driving voltage to be supplied to the electrooptic lens is controlled by a driving voltage controlling signal which is a sum of the differential signal and the focusing signal.

Abstract: A method and apparatus (30) for compensating for optical aberration created by a conformal window (60). The apparatus (30) comprises a one-dimensional corrector plate (32) for providing a varying amount of linear coma, first and second cylindrical lenses (34, 38) for providing a varying amount of astigmatism and a system for adjusting the corrector plate (32) and the lenses (34) and (38) to minimize the optical aberration created by the conformal window. The apparatus (30) of the present invention provides for correction of considerable amounts of optical aberration over a wide field of regard. The apparatus is simple in design, easy to install and cost effective.

Abstract: There is disclosed a raster output scanner for a color printing system which utilizes an indexed rotating polygon mirror in order to scan each given scan line from each latent image by a given facet in order to reduce misregistration caused by facet surfaces of a rotating polygon mirror.

Abstract: A polygonal mirror according to the present inventio is provided with a mirror body, a plurality of reflection faces formed to side surfaces of the mirror body, and reinforcing ribs integrally formed to both the upper and lower surfaces of the mirror body, respectively. Each of the reinforcing ribs has an outer circumference that is larger than the outer circumference of the mirror body.

Abstract: A fiber optic system is used in a laser ROS scanning system to generate a start of scan signal. In one embodiment, a single optical fiber is positioned at the beginning of a scan line sweep. The fiber transmits a portion of a scan beam energy, directed non-axially into the fiber entrance to a photosensor. The photosensor generates an output response which is processed to initiate the SOS signal. The fiber entrance face is formed so that the beam, entering non-axially, is either reflected internally along the fiber axis or first refracted and then reflected along the fiber axis. Dual fiber embodiments are also presented which detect and transmit non-axially incident scanning beams.

Abstract: An optical scanning system wherein a moving cylinder supporting a segment of recording media on its inner surface is axially moved over a pair of fixed cylinders. A slit is provided between the fixed cylinders, and a light beam is radially scanned by the system through and along the slit to scan the surface of the supported segment of media as the moving cylinder moves in an axial direction over the fixed cylinders and across the slit. A pressure source provides air to the moving cylinder, with the supplied air expelled from an inner surface of the moving cylinder against the fixed cylinders to form an air bearing. Air is also expelled into the area between the fixed and moving cylinders to float the media therein during media advancement. A vacuum source is also provided to draw air through the moving cylinder from the area between the fixed and moving cylinders holding the media against the inner surface of the moving cylinder while the media is being scanned by the light beam.

Abstract: An optical scanning device for leading a laser beam emitted from a semiconductor laser diode through a collimator lens, an imaging lens, and a cylindrical lens to a plurality of reflecting surfaces of a rotatable polygon mirror, and scanning a surface to be scanned movable in a vertical scanning direction with the laser beam reflected on the reflecting surfaces of the polygon mirror and transmitted through a correcting lens. The optical centers of the semiconductor laser diode, the collimator lens, the cylindrical lens, a return mirror, and the correcting lens are located in a plane containing an axis of rotation of the polygon mirror. The semiconductor laser diode, the collimator lens, and the cylindrical lens are located over an upper surface of the polygon mirror. Accordingly, an optical system can be formed in symmetry with respect to a center axis of an optical path of a horizontal scanning light beam from the polygon mirror without interference of the semiconductor laser diode, etc.

Abstract: Facet-to-facet pyramidal wobble is corrected without resorting to cylindrical optics by adapting agile beam concepts to provide real-time control of the light beam position on the photoreceptor. The agile beam is provided by either or both of a variable wavelength light source or a variable index of refraction prism. The position of the light beam is determined by either or both of a super linear position detector directly detecting the position of the light beam, or a facet detector and a look-up table for indirectly estimating the position of the light beam. By actively compensating for pyramidal wobble, the passive but expensive and difficult-to-position cylindrical optics can be replaced with cheap and easy-to-position spherical optics.

Abstract: A rotary scanner having a mirror with a plurality of deflecting facets for deflecting a light beam and a motor for rotating the mirror. The motor has a plurality of commutator segments and brushes, and at least one commutation position can be seen from outside. Further, the commutation positions are located at corresponding points with borders among the deflecting facets of the mirror.

Abstract: A wobble correction and focusing optical element for a raster optical scanner combines a toric lens, which provides most of the optical power for focusing the light beam to a scan line, with a binary diffractive optical surface, which corrects the field curvature of the toric lens and which also linearizes the scan. The diffractive surface will have a multi-level structure (binary diffractive optical surface) which possesses a diffractive phase function that will flatten the field curvature of the toric lens.

Abstract: An optical beam scanning apparatus which includes: an optical modulator which emits an optical beam in a direction corresponding to the frequency of an inputted signal; scanning device for scanning the optical beam; a scanning lens; a storage device which stores data for correcting the displacement of the optical beam passing through the scanning lens caused by an aberration of the scanning lens for each scanning position of the optical beam; and a device which, based on the data stored in the storage device, alters the frequency of the signal to be inputted to the optical modulator for each scanning position of the optical beam so as to correct the displacement of the optical beam caused by the aberration of the scanning lens.

Abstract: A video clock signal generator comprises: means for supplying a light beam; a mask having opposite ends spaced by a predetermined distance; a vibration scanner for reflecting the light beam and forming a light spot vibrating on the mask beyond the opposite ends thereof; a detector for generating an output signal representing optical information from the mask; a counter for counting a time required for the light spot to cross the opposite ends of the mask based on the output signal of the detector; and a control unit for controlling an amplitude of the scanner mirror in accordance with the time counted by the counter.

Abstract: A rotary mirror system for angularly deflecting a light beam including an air bearing arrangement rotatably supporting a mirror body on which one or more mirror facets are provided, the mirror body being the rotor of an electric motor, wherein the mirror facets are the side surfaces of an internal pyramid or frusto-pyramid formed in and opening towards one axial end surface of the mirror body and having an axis of symmetry coinciding with the rotational axis (A) of the mirror body, the orientation of the mirror facets, relative to the incoming light beam, being such that the reflected beam leaves the internal pyramid at an inclined angle with respect to the rotational axis (A).

Abstract: A circular arc illumination apparatus includes a light source section for emitting rays, a condensing optical system for condensing the rays emitted by the light source section, a rotating mirror driven by a motor and reflecting the condensed rays from the condensing optical system, and a circular arc-shaped bending mirror for reflecting the rays reflected by the rotating mirror toward a mask so that the rays become incident on the mask. The apparatus effectively utilizes light emitted by the light source section, exposes an object uniformly, and is practical and economical for exposing a large substrate.

Abstract: The present invention is a scanning system and a novel method for compensating for the variations in the output power of the beam from an A-O cell. The novel method involves varying the amount of drive current through the laser diode in such a fashion as to compensate for the loss of power due to diffraction inefficiencies. The amount of driving current is dependent upon the amount of power desired in the output beam from the A-O cell. The system and method of the present invention sets the output power from the A-O cell to a desired value. As the diffraction efficiency increases at other portions of the scan, the drive current is cut appropriately to compensate for the increased efficiency; thus keeping the output spot power at the desired value. Likewise, as the diffraction efficiency decreases at other portions of the scan, the drive current should be increased to compensate for the decrease in efficiency; thereby maintaining the desired value.

Abstract: Optical scanner, comprising a laser source for generating a laser beam, a first deflector for deflecting the laser beam towards a array of reflectors, the first deflector and the array of reflectors being rotatable relative to each other about a first axis, drive means for providing a rotation, and at least one detector for detecting backscattered light, further comprising a second deflector being rotatable about a second axis for deflecting the beam reflected by the array of reflectors in a direction substantially parallel or coincident with the second axis.

Abstract: In an optical scanner, a light source emits a light beam and a coupling lens changes this light beam to a convergent, divergent or parallel light beam. An optical deflector deflects the light beam from the coupling lens at an equal angular velocity. The deflected light beam is converged onto a scanned face by an image forming mirror and an elongated cylindrical optical element to perform an optical scanning operation at an equal speed. An optical path separating device separates an optical path of light reflected on the image forming mirror from an optical path of incident light from the light source to the image forming mirror. A reflecting face of the image forming mirror is constructed by a coaxial aspherical surface.

Abstract: An optical system for scanning a light beam across an object where the light beam is double reflected by the reflection surfaces of a rotating polygonal mirror. Beam expander optics are included in the light path for the light beam following the first reflection by the polygonal mirror to magnify the beam diameter to fill the length of the reflective surface of the polygonal mirror at the second reflection. The beam expander optics further include lenses for demagnifying scan angle in the light beam following the first reflection. The lenses of the beam expander optics are formed with a Petzval curvature (third order Seidel aberration) to correct for the distortion induced in the optics image plane by the longitudinal shift in the entrance pupil position at the first reflection as the polygonal mirror rotates.

Abstract: A circular arc illumination apparatus includes a light source device, a condensing optical system for condensing rays emitted by the light source device, and a scanning optical system for transmitting the rays to an object to be scanned. The scanning optical system includes a driving device, a rotating mirror driven by the driving device, an angular velocity detecting device for detecting an angular velocity of the rotating mirror, a controller for controlling the driving device based on an angular velocity of the rotating mirror detected by the angular velocity detecting device so as to vary the angular velocity in one time scanning, and a circular arc-shaped bending mirror for reflecting scanning rays reflected by the rotating mirror to the object. The axis of the bending mirror is coincident with a rotary axis of the rotating mirror.

Abstract: Disclosed is a scanning device (10) having a very fast raster scan and a small angle field of view. The scanning device (10) incorporates a rotating polygon scanning wheel (12) in which a beam of light (24) is reflected off of a first facet (14') of the wheel (12). A reflected beam (32) from the first facet (14') is directed through an optical subsystem that reverses the scanning direction of the beam and redirects the beam onto a second facet (14") of the scanning wheel (12). Since the subsystem optics reverses the scan of the beam, the second facet (14") scans the beam in an opposite direction to that of the first facet (14') and only the difference between the two scans remains. In a first embodiment, the optical subsystem magnifies or demagnifies the beam such that the angle of scan is enlarged or reduced, and thus the second scan will not completely cancel the first scan. Consequently, a very narrow field of view of a particular scene can be scanned very quickly.

Abstract: In an optical positioning system for at least two picture elements, a wavelength-dispersive, first light-deflecting element is used which deflects light beams in a first deflection direction according to their wavelength. In order to enhance the positioning speed, the optical system comprises two narrow-band light sources with a controllable wavelength for every picture element. The first light-deflecting element is arranged in the beam path of a second light-deflecting element with which an additional, essentially wavelength-independent deflection can be implemented. The range of deflection of the first light-deflecting element is thereby noticeably smaller than that of the second light-deflecting element. The ray beams of the light sources charge or impinge upon the wavelength-dispersive element in common.

Abstract: In an overfilled ROS polygon system, the total optical path length is minimized by focusing modulated laser beams onto the polygon facets in the cross scan direction by placing a single cylindrical lens between the laser diode and a collimator lens. The combined cross scan power of the cylinder lens and the collimator lens provides the cross scan focusing at the required high magnification.

Abstract: A compact beam scanning information readout device and method for reading bar code or other information requires little or no orientation of the information to be scanned by virtue of its raster or omni directional scan capabilities. Only a single mirror is needed to generate two dimensional scans. A wide range of scan speeds are also possible for simple or complex one or two dimensional patterns. Scanning in two dimensions may be done with independent and continuous control of the scan in each dimension. The scan patterns may be electronically controlled to instantly achieve various orientations ranging from a straight line rotated about a point to continuously rotating complex patterns. A light collector, light detector, processor, and means of signal transmission are also included. In one embodiment the device is packaged in a housing resembling a wand or a thin flashlight and in another embodiment the device is packaged in a ceiling mountable housing which will not interfere with counter top work space.

Abstract: A multichannel imaging spectrometer for airborne geological, geophysical and environmental surveys in a moving vehicle. An optical scanner employs a rotating polygon allowing reduced scan optics with increased data acquisition efficiency. Multiple spectrometers integrally registered allow channelization of the received signal to optimize noise performance in the range from ultraviolet through infrared. Output data is in a form for recording and real time display. A staring mode configuration provides enhanced sensitivity by using a two-dimensional detector array and adjustable mirror orientation. A scanning mode embodiment employs a two-dimensional detector array with time delay integration and three-dimensional storage of temporal spatial data and spectral wavelength and intensity. Thus, all channels are acquired simultaneously, resulting in perfect band-to-band registration with continuous spectral curves over the field of view.

Abstract: A scan optical apparatus is provided with a first light source for generating a beam for scan optically modulated based on an image signal, a second light source for generating a beam for jitter amount detection, a scanning device for deflecting the beams from the first light source and from the second light source to scan a surface to be scanned, an optical member disposed in the vicinity of the surface to be scanned or at a position substantially optically equivalent to the surface to be scanned, and a detecting device for detecting a beam reflected by the optical member and deflected by the scanning device. The optical member may have reflective portions and nonreflective portions which are repeatedly arranged in a main scan direction, or may be a corner cube array in which a plurality of corner cubes are arranged in the main scan direction. Further, the surface to be scanned may be a recording medium in a recording apparatus.

Abstract: A dual reflection unpolarizing monofacet (DRUM) scanner or beam deflector is made up of two essentially identical 45.degree. right angle prism elements with their hypotenuse faces together to form a body which may be rectangular or cylindrical and may be contained in a housing which provides for aerodynamic stability when the scanner rotates at high speed. The hypotenuse faces have a partially reflective surface on which an incident beam, collinear with the rotational axis, is incident. This beam is transmitted and reflected to provide dual beams, one of which is absorbed by light absorbing material, preferably a coating, on a surface of the body and the transmitted beam is retroreflected by a mirror on another surface of the body, back to the partially reflective surface. An output beam is provided by the retroreflected beam.

Abstract: A sensor for a raster scanner is disclosed which utilizes two elements to detect the position of a scanning light beam relative to a reference level and also detect the start of the scan position. The two elements are placed adjacent to each other in such a manner that on a reference axis, the width of both elements are equal. Each element will have a varying distance between its edges scanned by a spot and such distance on one element will be different than the corresponding distance in the direction of scan on the other element except at the reference axis. Depending on the distances traveled by the light beam on each of the elements, the position of the light beam relative to the reference axis will be detected. The two edges of each element that are adjacent to each other, separating the two elements, must be parallel to each other and orthogonal to the scan direction to also use the crossing of the edges by a light beam as a start of scan detector.

Abstract: The pre-polygon scanning path length of a raster output scanning system is reduced by replacing a required cylinder lens, or lenses, with two cylindrical mirrors. One mirror with a negative, concave surface and a second positive cylindrical mirror. The first mirror directs the light beam to the second mirror. The second mirror directs the light onto the facets of a rotating polygon to form a focused beam in the vertical axis of the polygon. The function of the two cylindrical mirrors is to act as a telephoto lens to properly focus the image of the laser at the polygon facet while reducing the total pre-polygon path length.

Abstract: A step stare scanning device includes a mirror with a plurality of facets mounted to a mechanism which substantially simultaneously rotates the mirror about a first axis while orbiting the mirror about a second axis. The rotating and orbiting motion creates a step stare scanning pattern from a constant rotary input. The field of view of an associated detector array is increased while minimizing detrimental effects of known stop-start mechanisms.

Abstract: A scanning infrared sensor has a continuously rotating head to which is mounted an infrared telescope with a two-dimensional detector array. Blurring of the image output by the detector array is avoided by means of a fast steering mirror positioned on the head at the input of the telescope. The fast steering mirror is rotated in an opposite sense to the sensor head so that the array stares at a region of space for a sufficient time to allow the capture of an unblurred image from the detector array. The mirror then flies back to a starting position and then begins to rotate once more in an opposite sense to the sensor head so that the array stares at a further region of space, and so on.

Abstract: A laser beam particle-detecting apparatus can automatically detect the position of minute particles on a substrate. A laser beam can be scanned across the substrate, and optical detectors can optically detect the laser beam after incidence with the substrate to define the position of any minute particles. Correction factors characteristic of the laser beam particle-detecting apparatus can be utilized to adjust the coordinates of the particle position, whereby any inaccuracies in the detecting apparatus can be compensated.

Abstract: A scanning device for an electronic photography printer which comprises a photosensitive drum, a rotary cylinder horizontally disposed and provided with spiral slits which are spaced from one another, an LED array horizontally penetrating the inside of the rotary cylinder and having a plurality of LEDs which are disposed on the LED array and each having a width of the same distance as the space between respective spiral slits of the rotary cylinder, a horizontal slit plate disposed between the photosensitive drum and the rotary cylinder and having a plurality of slits which are inclined on the basis of the horizontal line of the horizontal slit plate and spaced from one another, and a self-focus lens array horizontally disposed between the photosensitive drum and the horizontal slit plate.

Abstract: A projection exposure apparatus includes a first stage for supporting a first object; a second stage for supporting a second object; a projection optical system for projecting an image of the first object onto the second object; an image pickup system having a predetermined image pickup surface and being arranged to illuminate a mark of the first object with a radiation beam such that, with a reflected beam from the first object resulting from the illumination, a first image of the mark of the first object is projected onto the image pickup surface and that, with a reflected beam from the second object resulting from the illumination and being directed to the image pickup surface through the first object, a second image of the mark of the first object is projected onto the image pickup surface; and a detecting device cooperable with the image pickup system, for detecting a deviation of the surface of the second object with respect to a plane on which the image of the first object is to be focused, on the basi

Abstract: The device comprises a structure (1) supporting a light beam source (2), a beam guide and a camera assembly (3), the light beam source (2) being arranged to direct an outgoing beam of light (I) into the beam guide which projects the outgoing beam (P) onto a target surface to sweep the beam around an endless path (E) on the target surface, scans synchronously around the endless path (E) to receive light returning from the portion of the path (E) illuminated by the outgoing beam (P), and directs the returning light (P) onto a light sensor (12) provided in the camera assembly (3); the beam guide comprising a rotatable wedge prism (5) arranged such that the outgoing beam (2) is transmitted through relatively inclined surfaces (9, 10) of a projecting element of the prism (5) as it is rotated to direct the beam (P) to sweep around the endless path (E) and the light returning from the portion of the path illuminated by the beam (P) is received through relatively inclined surfaces (9, 10) of a receiving element of th

Abstract: An apparatus for detecting particles on a substrate incorporates a calibration system to correct any change in the angle of swing of a beam scanning mirror over a period of time. A pair of optical detectors can be positioned within the optical path between the scanning mirror and the substrate to provide a fixed reference point from which positional adjustments or calibrations can be made over the life of the instrument to eliminate any drifting of the positional signals of the actually detected particles on the substrate.

Abstract: Optical scanning system to scan a code on an object comprising a laser source (1), a laser beam shaper (2) receiving a laser beam from the laser source and focussing the laser beam on the object, a mirror polygon (4) having facets (6-9), of which at least one is reflective, and being rotated by a motor (5), a mirror array (10) surrounding the polygon arranged in such a way that the laser beam will generate a scanning pattern (3) on the code to be detected, and a detector (24) receiving the light scatterred by the object, in which system the mirror array (10) is substantially entirely surrounding the polygon (4); the polygon (4) is designed to perform an optical chopper function, in such a way that during one rotation cycle of the polygon (4) each mirror (11-22; 61-75) of the mirror array (10) will at least once receive the laser beam and generate its own scanning line.