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: An apparatus for detecting the longitudinal edges of a rod-shaped object moving in its longitudinal direction, in particular a tobacco or filter rod, comprises a light source, at least one beam divider for dividing the light beam coming from the light source into at least two light beams sweeping over the edge regions of the object, an optical deflection system for sweeping the two light beams over the object, two photodetectors for the light beams and an evaluating means for determining the position of the longitudinal edges from the instants of the bright/dark transitions at the two photodetectors on the one hand and the instantaneous positions of the light beams on the other hand. The or each beam divider generates two light beams which are parallel to each other and move in opposite directions over the object.

Abstract: Optical metrology method and apparatus in which the sheared portions of an optical image are automatically aligned so as to enable the widths of high contrast lines to be measured using optical image shearing. A mechanism splits a line image of an object into two, shears the two images and records the displacement distance, and an imaging system e.g. a television camera generates an electronic signal which represents the intensity profile of the sheared image in a direction perpendicular to the line image and parallel to the direction of shear. The intensity profile of the sheared image is sampled and digitized, and the digital signal is correlated with a digital filter. A mechanism then adjusts the shearing to a position given by an electronic signal, and the two positions taken up by the shearing mechanism are recorded, the difference therebetween is calculated, and then multiplied by a calibration constant, to provide line width information to be displayed on a display device.

Abstract: The force measuring apparatus includes a single-mode optical fiber having a defined anisotropy, whereby coherent light suppled to one end of the optical fiber is guided as two waves having linear orthogonal polarizations, respectively. The optical fiber is arranged between a pair of parallel planar pressure plates, the orientation of the optical fiber being such that the aforementioned linear polarizations are parallel with and normal to the remote surfaces of the pressure plates, respectively. Upon the application of a force to be measured in the compressive direction normal to one remote surface of a plate, a phase shift is produced between the waves which is a function of the magnitude of the load to be measured, as determined by interferometer means arranged at the other end of the optical fiber.

Abstract: An inspection device for visually ascertaining the desired alignment of a contact lens in a tinting fixture comprises a base and a platform having a flat surface and mounted to the base for rotation relative thereto. The device also includes an arrangement for mounting the fixture for rotation in unison with the platform and for aligning the fixture relative to the platform flat surface in such a way as to maintain the contact lens in an alignment wherein substantially the entire peripheral edge thereof is located in a plane substantially parallel to the platform flat surface, if the contact lens is in the proper desired alignment in the tinting fixture, and such that the tinting fixture is centered relative to the center of rotation of the platform.

Abstract: An optical apparatus for precisely measuring the dimensions of an object comprises an objective lens for forming an enlarged image of the object, a screen member onto which the enlarged image by the objective lens is projected and which is movable in a direction parallel to one direction on the image plane of the enlarged image, the screen member including a slit formed perpendicularly to the one direction, and a reflecting surface which is provided in an area including the surroundings of the slit and onto which the enlarged image is projected, observation optical means for observing therethrough the enlarged image on the reflecting surface, the observation optical means having a relay lens, and a field lens provided in opposed relationship with the reflecting surface of the screen member, the imaging light beam of the object from the objective lens passing through the field lens onto the reflecting surface of the screen member, the imaging light beam of the object reflected by the reflecting surface of the

Abstract: An inventive headlight optical axis aiming measuring apparatus and method is disclosed. The apparatus includes a head measuring horizontal and vertical inclinations of a front lens surface (34) of a headlight (12) installed in a vehicle (2) and including a plurality of contact-type displacement sensors (48, 49, 50, 51), each of which is associated with a device (28, 29, 30) in contact with the front lens surface (34) and moving in accordance with the inclinations of the front lens surface (34), a support (15) for the displacement sensors (48, 49, 50, 51), and device for checking the headlight optical axis aiming in accordance with a fixed relationship between inclinations of a headlight optical axis and the front lens surface (34) by means of outputs of the measuring head (9). In accordance with this invention, the headlight need ot come on and a large space is not required for projecting the headlight beam onto a screen.

Abstract: Lens meter and method of measurement of progressive multifocal lens using the same which is able to set the amount of movement of the lens and to simply position a far- or near-distance refraction characteristics-measuring portion of a progressive multifocal lens. In accordance with the method the optical center of a lens is first found from measurement employing the lens and using the optical center as point of origin, the lens is moved by a distance up to the far-distance refraction characteristics measuring portion and the near-distance refraction characteristics measuring portion of the lens mentioned by the lens manufacturer, so as to effect alignment with the measurement optical axis of the lens meter, thereby measuring the refraction characteristics of each measuring portion.

Abstract: A laser beam from a source 20 is used to provide a reference in space adjacent a portion of a structure movements of which are monitored. The beam is received by a receiver 30. A number of targets 300 may be mounted to move with parts of the structure extending alongside the beam path. Target constructions (FIGS. 6-8) are described which allow for normal passage of the beam past the target but which enable the position of the beam relative to a given target to be measured by intercepting the beam. In a variation (FIG. 13) for civil engineering use, a single target is selectively mountable to one of a number of supports. Another variation (FIG. 11) uses graduated mesh targets on which the beam impinges on each mesh but is also transmitted through the mesh. Dynamic movement of a part of structure such as a bridge is measured with a single target attached to the part in question and comprising a barred reflective assembly (FIG. 3), a fibre optic array (FIG. 4) or a position sensing photo-diode (FIG. 5).

Abstract: A plurality of test cells in a cuvette is optically measured while the cuvette is manually moved through a sensing light beam. The cuvette is exposed in an open channel exposed to ambient light and is manually moved through the sensing light beam at an arbitrary rate. Abrupt changes in the optical density sensed by the beam are used to trigger the storage of the light beam intensity as an accepted measurement. The abrupt change is determined by comparing the currently read optical density of the cell against a predetermined moving average of previously read optical densities. A modulated sensing beam is received by a photodetector and converted from an analog to a digital signal by a fast A-to-D converter. The output of the A-to-D converter is coupled to a central processing unit which also includes as its input a bar code reader reading from a optically coded strip such instructions which are necessary to describe the number of cells, the test to be determined and other processing or reporting information.

Abstract: Light reflecting means 2R and 2L provided on both sides of a road 1 each reflect an incident light at the same angle as the angle of incidence with respect to the plane of incidence. Lights 8R and 8L emitted from a moving vehicle 3 are reflected from the light reflecting means 2R and 2L and returned again to the light emitting source and accordingly they are detected by light receivers 75R and 75L. The position of the moving vehicle 3 is calculated geometrically based on the moving distance of the moving vehicle 3 in a period obtained from the difference between the light receiving time of the light receiver 75R and that of the light receiver 75L or the light receiving angle as well as the moving direction of the moving vehicle 3 and the positions where the light reflecting means 2R and 2L are installed.

Abstract: An uneven-surface data detection apparatus, includes a transparent plate having an uneven-surface contact portion against which an uneven surface to be detected is pressed. A light source illuminates the uneven-surface contact portion through the transparent plate. An uneven-surface image drawing out optical element draws out the light reflected on the uneven-surface contact portion of the transparent plate. A detector detects the light drawn out from the transparent plate by the optical element.Light reflected by a projection-facing portion of the uneven surface contact portion to be introduced into the detector diverges from a propagation direction of light reflected by a recess-facing portion of the uneven surface contact portion. The optical element is arranged to guide the light reflected by the projection-facing portion into the detector.

Abstract: A Moire system for linear measurement of an unknown distance defined by two surfaces, a collimated light source, a first grating between light source and the surfaces, a second grating positioned to receive collimated light from the surfaces after the light has reached the surfaces from the first grating, the first and second gratings being rotated relative to each other by a small angle .theta., a screen located after the second grating for receiving Moire patterns caused by the first and second gratings, and a mechanism for shifting the patterns as a function of the unknown distance whereby measurements of the amount of shifting is determinative of the unknown distance.

Abstract: A method whereby the circuit pattern on a photographic mask or a reticle used in the manufacture of semiconductor devices is inspected for defects by an image processing technique. In this inspection method, the pattern of the mask is printed on a photosensitive member prepared by forming an opaque or semitransparent photosensitive layer on a transparent substrate and an image of the printed pattern formed on the photosensitive member is inspected by the image processing technique.

Abstract: An alignment device for aligning a reticle and a wafer with the aid of a projection lens system for projecting an integrated circuit pattern of the reticle onto the wafer, wherein a light beam from the wafer is passed throught the projection lens and is directed by way of an objective lens to a spatial filter to detect a positional relation between the reticle and the wafer. According to the position of an optical axis of the objective lens relative to an optical axis of the projection lens and according to the telecentricity of the projection lens, the spatial filter is displaced relative to the optical axis of the objective lens, whereby a particular component of the light beam from the wafer is positively extracted out, without being affected against by displacement of the objective lens for the alignment operation.

Abstract: The surface texture of a moving transparent film is determined by applying a beam of collimated electromagnetic radiation at an angle of incidence sufficient to produce detectable backscattered radiation; collecting the backscattered electromagnetic radiation while avoiding specularly reflected radiation; and evaluating the intensity of the collected radiation for two components, a first component corresponding to the haze percent of the film and arising from the scattering of the collimated electromagnetic radiation by microscopic and submicroscopic features of the film surfaces, and a second component produced by the scattering of the collimated electromagnetic radiation by macroscopic surface blemishes, gouges and gel-like particles on each surface of the transparent film.

Abstract: A system for detecting the presence or absence of a vehicle in front of a subject vehicle and method therefor, wherein a plurality of wave transmitters transmit distance measuring media such as laser beams or electromagnetic waves over a front detection area toward which the distance measuring media are transmitted in mutually different directions and through respectively predetermined angles with respect to a longitudinal axis of the subject vehicle. In the detecting system and method, the presence of the preceding vehicle is determined on the basis of propagation delay between the times at which at least one of the waves is transmitted and at which the reflected waves are received. The lateral progress of the vehicle in front of the subject vehicle from detection area to detection area is monitored to maintain contact with the detected vehicle even around curves or during steering adjustments.

Abstract: The measuring device is used for determining a relative position between a first item and a second item or the image thereof. The items are displaceable or rotatable relative to one another. The first item has a code carrier, which is arranged along a path. The code carrier is provided with a code pattern at right angles to the path. The second item has a code reader oriented on the code carrier path. A computer is connected downstream of the code reader and has means for quantifying the signal supplied by the code reader and for comparing with a stored code image of the code carrier, as well as for calculating the relative position from the comparison result. This measure permits automatic reading of the position, accompanied by a very high measuring accuracy. The measured result can be digitally displayed and, if required, can be directly stored on a data carrier and/or can be further processed in a computer.

Abstract: Printed webs leaving a printing press at speeds above 500 feet per minute are inspected with precision across the full width of the web by a stroboscope method and apparatus. Each repetitive image or design imprinted on the high speed web is rendered stationary relative to the eyes of a viewer at a web inspection station by bright short flashes of light emitted by an elongated xenon flash tube or tubes spanning the web transversely of its path of movement. Filtered light flashes are triggered by an improved strobe circuit which is synchronized with the press at all times and permits an inspector to produce from one to six equally spaced images per press cylinder revolution. Additionally, the system can be used in either an image lock mode for side-by-side comparison with a standard or in a controlled pan or scroll mode to allow optimal inspection of entire impression sequences. Also, when desirable, both sides of the web can be inspected by utilizing a second flash tube configuration located behind the web.

Abstract: A plurality of sample beam wavefronts derived from selected portions of a wide-aperture outgoing optical beam wavefront enter an entrance pupil (11) located adjacent a focal surface (12) on which the sample beams are individually focussed. A relay lens system (13) transmits the sample beams to a beam splitter (14), which divides each of the sample beams into an undeviated component and a diviated component. The undeviated components of the various sample beams image the entrance pupil (11) on a first scanning mirror (15), and the deviated components image the entrance pupil (11) on a second scanning mirror (16). The focal surface (12) is reimaged by the relay lens system (13) onto focal planes (17 and 18), respectively, so that the foci of the individual sample beams appear as spots on the focal planes (17 and 18).