Abstract: The sensor for detecting and measuring the angle of rotation of the polarization plane of light delivered by a sensitive system (19) subjected to an external phenomenon such as a magnetic field, for example, with the sensor being connected via an optical fiber (18) to a source of incoherent light (10) and essentially comprising the sensitive system (19), a quarterwave plate (22), a birefringent crystal (24), and an analyzer (26). The light flux provided by the sensor is spectrally modulated as a function of the angle of rotation of the plane of polarization of the light delivered by the above-mentioned system (19).

Abstract: When a microfiche is automatically retrieved by a microfiche retrieval device, and the data of a target frame is input from the keyboard, the microfiche is conveyed to automatically retrieve the frame at the position relevant to the input data, and the largest frame is projected on a reader screen. The positional data for retrieving frames corresponding to the frame addresses other than that of the target frame and the fiche-mode data necessary for retrieving and outputting the imaged frames is stored in memory prior to retrieval of a frame. The stored data is read out so that the correct frame can be retrieved. Even if frames are not positionally aligned with the feeding direction of a particular microfiche or even if the reference frame or the maximum address frame is not exposed on a microfiche, frames can automatically be positioned at a high speed simply by designating a plurality arbitrary frames which are actually exposed with images.

Abstract: A device for detecting the inclination of a surface to be examined is disclosed. The device includes an optical arrangement for directing a radiation beam to the surface to be examined, an arrangement for receiving a reflected beam from the surface to be examined and for outputting a signal corresponding to the inclination of the surface to be examined, and a device for changing the size of the beam on the surface to be examined or the size of the beam at a position which is substantially optically conjugate with the surface to be examined.

Abstract: Optical apparatus for measuring angles to a precision approaching the theoretical optical limit for a fixed aperture. Calculations and measurement of the angle are made on the basis of the displacement of a very detailed waveform on a multi-pixel detector from a known point on the detector. The angle this displacement represents is created by the angular displacement of a dispersive element attached to the object of interest. The beamline comprises an optical source, the dispersive element on the object, and a spectrometer which contains an echelle and the detector. The known point on the detector is established by aligning the beamline to a fiducial angle.

Abstract: A method and apparatus measuring the orientation of the body in space with respect to first, second and third orthogonal axes, by projecting a collimated beam of light onto a non-axially-symmetrical mirror carried by the body in space; directing the light beam reflected from the mirror through an instrument measuring beam deflections or curvatures; and measuring the beam deflections or curvatures about the three axes to determine the orientation of the body in space.

Abstract: A mask structure and a mask positioning device, executes accurate and quick positioning of a mask having a generally ring-like shape. The mask structure includes a supporting frame of a generally ring-like shape, and at least one flat surface formed by a mirror surface is provided at a peripheral part of the supporting frame. Light is projected upon the flat surface and, on the basis of detection of reflected light therefrom, the mask can be positioned with respect to the rotational direction, the inclination and orthogonal coordinate position. The mask positioning device is adapted to execute such positioning accurately and quickly.

Abstract: A device for electro-optical monitoring of angular and lateral deflections of a moving carriage relative to a stationary track along which it moves, including a transmitting unit mounted on the moving carriage and including a light source illuminating a pattern, a receiving unit mounted on the track in light receiving relationship with the transmitting unit and including optical sensor apparatus for sensing the light transmitted from the transmitting unit and providing an output signal corresponding thereto, and a micro computer arranged to receive the output signal from the receiving unit and to determine the angular and lateral deflection of the carriage utilizing the information derived from the signal.

Abstract: An apparatus for measuring the length of a sheet moving at a constant speed in one direction comprises front and rear edge detectors for detecting front and rear edges of the sheet to output front and rear edge signals, respectively, and an angle detector for detecting the angle at which the sheet moving in that one direction is inclined relative to that one direction to output an angle signal representative of the angle of inclination. An arithmetic circuit operates to calculate an apparent length of the sheet in the direction based on the front and rear edge signals and to correct that apparent length of the sheet with the angle signal so as to determine the actual length of the sheet.

Abstract: Conventionally, high-speed cameras are used to record the ejection of a store from an aircraft. The subsequent processing and analysis of the high-speed films are usually quite costly. The present invention system substantially reduces the cost of such processing and analysis by implementing a plurality of electro-optic sensors to detect sequentially individually energized LEDs mounted onto the to be ejected store. To sequentially activate the LEDs, receiver decoder electronics, located on the store, are used--provided signals are sent thereto by a radio control transmitter located in the aircraft. By formatting the data received by the electro-optic sensors, the different positional characteristics, such as the pitch rate, the velocity, the yaw rate and the roll rate, can be calculated in real time, either on board of the aircraft or at a remote location, the raw data having been transmitted thereto by means of a telemetry system, also located within the aircraft.

Abstract: A system of optimizing the volume of boards that may be cut from a log provides for one surface of a cant to be cut with a curved or straight surface. This takes into account curved, tapered or straight logs. The system comprises a scanner positioned to scan the log and determine an optimum cut surface profile, a cutting head positioned to cut the top surface of the log, the cutting head having relative vertical movement to the top surface, a conveyor to convey the log passed the scanner and the cutting head, and a controller to control the relative movement of the cutting head in accordance with the signal from the scanner to produce the predetermined optimum cut surface profile for the top surface of the log.

Abstract: An apparatus for aligning a wafer. The edge of a wafer is mapped by means of a photodetector array and a light source to provide a signal representative of the X-Y position and angular orientation of the wafer as the wafer is rotated one revolution on a shaft. The signal is digitized and processed to provide stored information of the X-Y position and angular orientation of the wafer. The shaft is then rotated to move the wafer from its calculated angular orientation to a desired angular orientation. The X-Y positional information may be used to center the wafer.

Abstract: A system and method are provided using a photodetector array for producing an output signal which is compensated for the effects of ambient light, photodetector bias, and the like, wherein the output signal contains information indicative of the position of the object. The preferred embodiment is useful for vehicular wheel alignment and includes left and right wheel units for coupling to respective left and right steerable wheels of a vehicle, and a central microcomputer and CRT display operably coupled with each wheel unit. Each preferred wheel unit includes a photodetector array operably connected to a wheel unit microcomputer and a laser beam source directing a laser beam toward the array of the other wheel unit.

Abstract: An active boresight drift measurement and calibration apparatus utilizing a predetermined number of interferometer units to measure the distances between themselves, the target tracking unit and the beam direction sensing unit. The interferometer units provide the initial alignment reference and by periodic repeat measurements provides distance change data to establish boresight alignment drift correction angles.

Abstract: Improved techniques are provided for alignment of two objects. The present invention is particularly suited for three-dimensional translation and three-dimensional rotational alignment of objects in outer space. A camera 18 is fixedly mounted to one object, such as a remote manipulator arm 10 of the spacecraft, while the planar reflective surface 30 is fixed to the other object, such as a grapple fixture 20. A monitor 50 displays in real-time images from the camera, such that the monitor displays both the reflected image of the camera and visible markings on the planar reflective surface when the objects are in proper alignment. The monitor may thus be viewed by the operator and the arm 10 manipulated so that the reflective surface is perpendicular to the optical axis of the camera, the roll of the reflective surface is at a selected angle with respect to the camera, and the camera is spaced a pre-selected distance from the reflective surface.

Abstract: Apparatus measures the scattered radiation received by a detector device in a measuring station (F) situated on the side of the beam path (O). The detector device has a sensitivity lobe which has a given limited lobe width (2.DELTA..theta.) and which lobe can assume different angles (.alpha.) relative to a reference line (R). In the measuring station (F) the time distance between the front flank and the rear flank of the scattered radiation reaching the detector device, i.e. the pulse width or the pulse length of the scattered radiation, is determined in at least two different angular positions (.alpha.) of the sensitivity lobe. The position of the light beam path is then determined by means of the measured pulse widths in combination with the associated known angular positions of the sensitivity lobe.

Abstract: An accurate and high-speed measurement of the vehicle wheel alignment is achieved by an optoelectronic, non-contact measurement system. This system includes photoelectric sensors for detecting the distance between a reference vertical plane and a tire side surface of each wheel, and a stepping motor for adjusting the position of the sensors to follow-up the displacement of the wheel in a direction parallel to the longitudinal axis of the vehicle. Operation of the stepping motor is controlled by a microcomputer on the basis of the updated distance data delivered from the sensor inputs. The microcomputer processes the input data to compute a toe-in or a camber of the wheel for the analog or digital display.

Abstract: Related systems and methods are described for determining the angular direction of an atomic beam relative to the beam's reference axis. For a non-relativistic atomic beam, a pair of counterpropagating, equal frequency laser beams intersect the atomic beam at a known angle to the reference axis, preferably perpendicular. The atomic beam direction is inferred from the frequency difference between resonant peaks in the laser beam fluorescence as the laser frequency is scanned. For a relativistic atomic beam, a pair of laser beams intersect the atomic beam from different sides at equal predetermined angles. The atomic beam direction is determined by observing the difference between resonant absorption peaks in the transmitted laser beam intensities as either the laser beam frequencies or laser beam angles relative to the atomic beam are varied. The angles between the laser and atomic beams are preferably selected to minimize the widths of the resonant peaks.

Abstract: A detector for aligning a laser beam has been provided. The detector includes an insulative substrate, and a thermally conductive planar face attached to the substrate. The face is divided into thermally isolated sectors, each sector having the same shape and area. A corresponding thermal sensitive device is provided for each sector. Each sector is in thermal contact with a corresponding one of the thermal sensitive devices, and each thermal sensitive device produces a response proportional to the amount of laser energy impinging thereon to thereby provide indication of the misalignment of the laser beam relative to the transport path.

Abstract: A line of sight aligning device for use with an optical instrument having a viewing opening requiring precise alignment with the line of a sight of the viewer. The device comprises a body member having an eye opening and nose recess in operative position relative to each other. Positioning means position the body member relative to the optical instrument with its eye opening aligned with the viewing opening of the optical instrument. On the front face of the body member, above the nose recess, is a straight edge positioned within the field of vision of the viewer and disposed substantially at right angles to the longitudinal axis of the nose recess in the body member.

Abstract: A method and an arrangement for aligning relative to each other a mask pattern (C) and a substrate (W) which are both provided with two alignment marks wherein by using two separate alignment systems (AS.sub.1, AS.sub.2) which are each associated with one mask mark (M.sub.1, M.sub.2) and which are each used for aligning the substrate marks (P.sub.1, P.sub.2) relative to said mask marks the substrate (W) and the mask (M) can be aligned accurately without referring to the frame of the exposure apparatus and in addition it is possible to detect magnification errors.

Abstract: Device for stabilizing the axis (11) of a variable field guidance system with respect to the axis (2) of a sighting device (1) in which the sight axis (2) is adjusted until it is perpendicular to a plane-parallel plate (3) forming an optical reference element. An angular movement of the guidance axis (11) is registered by an error measuring device having an aperture (13) which is arranged symmetrically to the optical center (9) of the guidance system with respect to a further plane-parallel plate (15) and a detector (14) which receives the flux from the guidance beam transmitter after successive reflections from the plane-parallel plates (3 and 15). The detector (14) is connected to the input of an error measuring receiver (16) which supplies an error signal which is applied to a correction element (17) in the guidance beam path.

Abstract: An apparatus for measuring a comprehensive state of vector displacement between a group of at least two pairs of longitudinally spaced side-looking radar arrays mounted upon a flexible host vehicle. This apparatus will operate to measure in three linear translation motions and three rotational motions, the relative positions of the radar array antennas upon the host vehicle during maneuvers of the host vehicle.

Abstract: The three-axis angular position of a tetrahedral reflector which is mounted on a platform or element is monitored by first and second optical apparatus aimed at the reflector at equal angles on opposite sides of the axis of the reflective element thereby providing off-axis viewing of the reflective element for monitoring the angular movement of that element. The first optical apparatus is an autocollimator having a source of radiation for producing a beam of radiation which is applied to a beam splitter through a collimating lens which is aimed at the reflector. The return image from the reflector is passed through the beam splitter to a detector. The second optical apparatus may simply be a receiver including a second lens in optical alignment with a second detector with the lens being aimed at the tetrahedral reflector. The second optical apparatus may be in the form of an autocollimator of the same type as the first optical apparatus.

Abstract: A laser system is provided for monitoring geometric errors in a machine, measuring apparatus or the like. The laser systems comprises at least one dual laser beam generator and at least one target assembly. The dual laser beam generator is operative to generate first and second tightly focused parallel laser beams. The target assembly comprises first and second targets in line respectively with the first and second laser beams. The targets are operative to sense the precise location at which they are impinged upon by the laser beams. The target assembly further includes a beam splitter that is operative to direct a portion of one laser beam through an angle. A third target is provided in line with the diverted portion of the laser beam. The three targets are operatively connected to a control means which utilizes the data sensed by each target to assess pitch, roll and yaw rotational errors as well as pure displacement errors.

Abstract: An apparatus and process for determining focus correction for a lithographic tool are provided. A periodic surface relief structure containing focus information is illuminated so that diffraction beams are generated. An object is translated orthogonally to the periodic structure to cause a change in the intensity of the diffracted beams. Focus correction is determined based upon the changes in the intensity of the diffracted beams.

Abstract: An apparatus and method for aligning a mask and wafer in the fabrication of ntegrated circuits utilizing alignment patterns on the mask and wafer. Each alignment pattern comprises a plurality of parallel alignment marks which are spaced from one another such that the patterns may be superimposed so that the marks of one pattern are positioned between marks of the other pattern. When the patterns are misaligned, a moire pattern is produced which disappears on alignment. The marks of each pattern are also disparately spaced from one another, permitting a gross to fine alignment. In aligning the patterns, each mark of one pattern is positioned between pairs of marks of the other pattern in an order corresponding to the widths of spaces defined between marks of the other pattern, progressing from the largest space width, giving gross alignment, to the smallest, giving fine alignment.

Abstract: An apparatus automatically for correcting tilt and focus errors of a wafer in a mask projection system for a plurality of subfields on the wafer which vary in position according to a known scheme. The tilt and focus of each subfield on the wafer is individually corrected by three axial actuators operating on the variable X and Y coordinates of the center of each subfield and its tilt and focus errors.

Abstract: A projection printing apparatus uses different lens systems during alignment and during printing. The lens system for alignment causes an alignment mark on mask to be imaged on the alignment mark on a wafer when the mask is illuminated by non-sensitizing light. The lens system for printing causes the circuit pattern of the mask to be illuminated by sensitizing light to be imaged on the wafer. The whole or part of the lens system for alignment is positioned outside of the circuit pattern image forming light path so as not to adversely affect the circuit pattern image on the wafer when the mask is illuminated by the sensitizing light.

Abstract: A scanning angle tracker which includes a laser beam and a beamsplitter for developing two beams which intersect on a scanning mirror. The scanning mirror sweeps the two beams across a retro-reflective tape on the object. Return signals are generated for processing to provide the desired angular information.

Abstract: A scanning angle tracker which includes a laser beam and a beamsplitter for developing two beams which intersect on a scanning mirror. The scanning mirror sweeps the two beams across a retro-reflective tape on the object. Return signals are generated for processing to provide the desired angular information.

Abstract: In a method and a circuit for determining a contour-defining angle formed by a contour in an image within a relatively small region thereof with a predetermined direction, the steps include selecting the region so that said contour passes as closely as possible through a center thereof, and subdividing the region into a number of sectors of substantially equal areas distributed substantially symmetrically about its center, and separated from one another by respective separation lines, the number being an even number and at least four, and one of the separation lines coinciding with the predetermined direction, obtaining brightness signals from each of the sectors in dependence of the proportion of the dark-to-light areas extending over each respective sector, generating difference signals from respective oppositely disposed sectors, processing the difference signals so as to identify the sector in which the transition from the light area to the dark area occurs, and determining by further processing the conto

Abstract: An adjustment and test device for a laser ranging system or laser range finder which device is adapted for obtaining the parallel alignment of optical axes of the transmitter and receiver with respect to one another and with respect to the optical reference axis, characterized by a test unit, an optical adapter unit and a mechanical adapter unit. The test unit has a housing, a collimator, which comprises a collimator lens, a beam splitting cube with a reticule, a device for illuminating the reticule and a device for observing the illuminated reticule, and an arrangement for mounting the collimator in said housing for adjustment of the optical axis of the collimator in the housing. The optical adapter unit has an independent housing and has an arrangement for optically coupling the test unit to the laser ranging system which includes at least one movable optical coupling element for interconnecting an optical axis of the laser ranging system to the collimator axis.

Abstract: Method and apparatus for testing the correspondence of the line of sight of optical instruments with the target line of weapons. A predetermined measuring field and a photoelectric line-type sensor are used. The nominal positions of the lines of sight and of the target lines relative to each other are stored as coordinates in a long-time memory. Simultaneously a nominal reference point as the origin of the coordinate system stored in the long-time memory is determined.

Abstract: The invention relates to a device for positioning an object relative to a carrier means, particularly for use in digital image conversion where an object has to be accurately positioned relative to the carrier means. This is achieved by tensioning said object by means of two strips and an elongated member to a mounting piece which moved by a displacement means positions said object. The positioning operation is observed through a measuring microscope.

Abstract: A method and apparatus is disclosed for determining the height, width, leh and orientation of an object from the feature image of the object found on oblique panoramic aerial photography. A magnifying eyepiece is provided with a calibrated reticle for measuring the dimensions of the feature image. The eyepiece also has a reference mark and indicia about the eyepiece for measuring the orientation from true north of the longitudinal axis of the feature image. The actual measurements of the object are quickly determined from the measurements of the feature image using a suitably programmed calculator supplied with the photograph and camera parameters.

Abstract: A mask alignment method of the projection type is disclosed which is based upon a fact that the exit pupil of a projection lens is actually positioned at a finite distance, and wherein a first wafer alignment pattern including a line segment and a second wafer alignment pattern including another line segment are formed on a wafer in those radial directions from the optical axis of a projection lens which intersect with each other approximately at a right angle. A first mask alignment pattern including a line segment and a second mask alignment pattern including another line segment are formed respectively at those positions on a mask which optically correspond to respective positions of the first and second wafer alignment patterns through the projection lens.

Abstract: The invention relates to an arrangement for measuring the position of an index of a surveying device comprising a flat-plate micrometer and at least one swinging index. The interfering oscillations, due to external influences, of the index in the course of a repeated measurement of a graduated circle interval are compensated by balancing the measuring frequency and the interfering oscillation frequency. The frequency of the interfering index oscillations is detected by photodetectors, and compared to the rotation speed of a servo-motor for initiating the frequency of the repeated index measurement both frequencies being adapted to one another via the rotational speed controlled by a frequency controlled unit.

Abstract: The invention relates to an arrangement for determining the vertical axis of a surveying device including a horizontal and a vertical circle each being provided with an index. The two indexes are related to each other and the resulting departure, if any, is measured either visually or physically. By virtue of the inventional arrangement additional means for determining the vertical axis of a surveying device such as inclinometers are eliminated.

Abstract: A reflector for electrooptical measurement of the distance between a first (3) and a second point (4) is arranged with a right angle sighting device (13) in a common case (8). The reflector (6) may thus be set up at a point (5) where the directions to the first (3) and second points (4) form a right angle. This facilitates the distance measurement between points (3, 4) that are not suited for the set up of reflectors or where visual contact between the points (3, 4) is impaired by an obstacle (1).

Abstract: This system permits the detection of rotational mis-alignment (i.e., twist) of two initially aligned, but separated, members. The two aligned members are linked by a single strand of focused optical fiber which, in combination with other co-acting components of the system, allows the user to detect rotational mis-alignment (i.e., twist) of the members, based upon the phenomenon that a single strand of focused optical fiber is functionally capable of conveying a formed, completed, and real image from one end of the fiber to the other end. Accordingly, one end of the fiber is attached to one member where an image is formed, and that formed image is transmitted to the other end which is attached to the other member where the transmitted image is sensed and compared to what the image should be if the members are still rotationally aligned. If the image that is received at the other end is positionally different (i.e., twisted), then the members are rotationally mis-aligned.

Abstract: A continuous flexible web includes a flat, flexible, non-conductive substrate with copper cladding on at least one major surface of the substrate. Prepunched holes may be formed in and through the web and may provide through-hole connections between printed circuits ultimately formed on opposite sides of the substrate.Successive sections of the web are indexed through a screen printing apparatus. A photocell system cooperates with preformed through-slots formed selectively in the web and windows formed in a platen beneath the section to precisely locate the platen with the section and relative to a circuit pattern formed in a screen above the section. The underside of the section is then held with the platen and the screen is positioned over the top side of the section. Ink is then flooded onto the screen and ultimately wiped through circuit-pattern openings in the screen and onto the section to form an inked impression of the circuit pattern on the section.

Abstract: A self-clocking digital position sensor having a main optical transmission line to which are coupled a multiplicity of branch optical transmission lines each of which is for transmitting one bit of position data. The branch transmission lines may be of unequal length or sequentially coupled along the main transmission line to provide a position data sequence of optical pulses reflected from a position coded device at an end terminal of the main transmission line for each optical pulse incident thereto.

Abstract: A composite indicator for use with overlay process color screen tints in offset color printing comprised of a composite screen made of relatively angled color screens. The respective dot patterns of the color screens have the word of the process color associated with that angle worked in by an out-of-phase dot pattern with respect to that screen background dot pattern. An overlaying color screen, when properly angled, causes, by out-of-phase moire pattern effect, the name of that color to be visually readable as a relatively lighter or darker pattern on a contrasting background.

Abstract: A modular encoder with a dimensionally stable housing which can be easily aligned for mounting on a motor housing. The encoder utilizes a monolithic, in-line, sensor array and a single light source to achieve improved long-term performance and includes improved alignment means permitting a user to readily align the encoder with a motor. Pre-alignment of the mask and sensor assembly simplifies the alignment performed by the user.

Abstract: A method and arrangement for aligning a mask comprising a mask-pattern relative to a substrate when the mask-pattern is repeatedly and directly imaged on the substrate, gratings in the mask and gratings on the substrate (phase gratings) being employed as alignment references. The gratings in the mask are located outside the mask pattern and the phase gratings are located on the substrate outside the area where the mask-pattern is imaged. The substrate (phase) gratings are imaged on one of the mask gratings with a projection system which is also used for projecting the mask-pattern on the substrate. The image of the gratings on the grating in the mask is adjusted. Thus, a very accurate alignment can be achieved.

Abstract: Electronically tunable optical filters are disclosed wherein a spatially varying dc electric field is applied to successive regions of a birefringent crystalline medium disposed between a pair of suitably oriented polarizers along the path of a light beam to be filtered. The dc electric field, which may be either parallel or perpendicular to the light path, electro-optically produces in the birefringent medium an effective oscillation of the optic axis of the medium about the pass direction of the input polarizer in a plane perpendicular to the light path as a function of distance along the light path with a predetermined spatial variation to achieve a desired filter transmission characteristic. The electric field is generated from programmable control voltages to provide a wide variety of filter passband or stopband characteristics.

Abstract: There is provided a technique and apparatus for aligning a mask to a substrate with high precision using Moire fringe effects produced by superimposing diffraction gratings. The gratings comprise first and second patterns of horizontal and vertical lines and spaces, respectively. The first pattern comprises horizontal and vertical lines and spaces of a first width. The second pattern comprises horizontal and vertical lines of a second width which differs from the lines in the first pattern by a small amount .DELTA.. The patterns are superimposed to provide a Moire fringe effect. When alignment occurs, a symmetrical pattern is provided. If misalignment in the X, Y or .theta. coordinate occurs, an assymmetrical or skewed pattern of Moire fringe effects is generated.

Abstract: Apparatus for indicating the instantaneous angular deflection of an object about a selected axis without mechanical contact with the object. Light from a light source is transmitted through a first flat refractor to a converging lens which focuses the light through a second flat refractor onto a differential photocell. The first flat refractor is attached to the object such that when the object is deflected about the selected axis the refractor is also deflected about that axis. The two flat refractors are identical and they are placed an equal distance from the converging lens as are the light source and the photocell. The output of the photocell which is a function of image displacement is fed to a high gain amplifier that drives a galvanometer which rotates the second flat refractor. The second refractor is rotated so that the image displacement is very nearly zero making the galvanometer current a measure of the deflection of the object about the selected axis.

Abstract: The invention relates to the positioning of an object comprising at least two fixed reference marks in an optical projection system. The system according to the invention comprises two projector arms illuminating two regions of the surface of the object through two marks, which form a reference system, having a variable inter-axis interval, display means enabling coincidence between the reference marks of the object and the reference system to be established.

Abstract: An aircraft weapon system including a component mounted on a wing of an aircraft and a radiation source and sensor arrangement for measuring changes in the alignment of the component with respect to a reference axis fixed with respect to the main body of the aircraft.