Abstract: A device for detecting the presence of contaminating water in a fuel tank as well as for measuring the density of the fuel in the tank which includes an elongated body of optical material arranged to be mounted in a fuel tank in a vertically extending position, one side face of the body forming an interface with the fluid in the tank, and a plurality of light sensors on the opposite face of the body arranged in spaced-apart relationship, together with light-emitting means at the bottom of the body which emit a divergent group of rays of successively increasing angles of incidence upwardly so that those rays exceeding the critical angle at the interface for a fuel of a specific index of refraction are reflected to illuminate those sensors corresponding to the rays exceeding the critical angle to thereby provide a detected output representing the density of the fluid, the light-emitting means providing a second group of rays striking the lower portion of the interface which are reflected when water is present t

Abstract: An optical presetter for precision alignment of a tool on a machine turret to be positioned on a lathe or the like. The presetter includes a base support, a light source, an adjustable carriage, and a viewer with a reference. When a tool is mounted on a turret and the turret is mounted on the carriage with the tool in the light beam; the tool can be precision aligned by moving the tool relative to the turret and noting the change of the tool image on the viewer.

Abstract: The invention relates to a generator of the harmonic of laser light destined in particular for application in the equipment for spectrometric measurements carried out with the laser technique. The substance of the invention is to shorten many times the optic route in the generator of the harmonic of laser light by the replacement of the system of elements of a zero dispersion by at least one dispersive element of a great dispersion, in particular by a rutile prism, combined with the system reversing the polarization surface by 90.degree., in partricular with a 90.degree. polarization rotator or a half-wave plate.

Abstract: A method and apparatus for rotating through a selected angle the polarization vector of a substantially linearly polarized electromagnetic beam by using three or four reflections with the output electromagnetic beam being substantially free of ellipticity. By selecting the second and third angles of incidence such that the ellipticity introduced by the second reflection is cancelled by the third reflection and the first and fourth angles of incidence which introduce substantially no ellipticity, the polarization vector of the incident electromagnetic beam need not be restricted to being parallel or perpendicular to the incident plane.

Abstract: For measuring the speed of movement of one phase in another, and particularly the rate of sedimentation of corpuscles in blood plasma, a container is filled with a blood sample, a light beam is directed through the container and an image of a vertical plane in the container traversed by the beam is formed in a measuring plane, the light intensity at two vertically spaced regions of the measuring plane is measured, the container is moved until a certain light intensity relationship exists between the two regions, indicating that the image of the boundary of the one phase in the other phase is located between the regions, and after a selected time interval the container is raised until the same light intensity relationship is established between the two regions and the distance through which the container has been raised is indicated.

Abstract: A building being erected is aligned with the vertical by projecting a main laser beam horizontally and splitting it into a vertically reflected test beam that is received on the building and used to ascertain proper alignment thereof with the vertical and a horizontally reflected adjustment beam that is received at a detector having an array of receptors around a central receptor. So long as the adjustment beam is received at the central receptor, the proper vertical positioning of the test beam is insured. If the adjustment beam moves off the center receptor, however, a positioning motor connected to the projector is actuated to reposition the main beam and the splitter to as to realign the adjustment beam with the central receptor and simultaneously realign the test beam with the vertical.

Abstract: The system of the present invention provides means for quick and accurate measurement of various wheel alignment parameters of motor vehicles by the use of reflected light beams. A laser source mounted near the front end of the vehicle provides a pair of light beams directed 180 degrees apart across the front end of the vehicle. Each of the beams is reflected along the side of the vehicle by a roof mirror set mounted near each front corner of the vehicle. The mirror sets each deflect a beam through a constant net angle of 90 degrees for a wide range of angles of incident light so that the laser source can be rotated to quickly provide parallel beams which are aligned substantially parallel to the sides of the vehicle. These mirror sets also provide stable beams and present small movements thereof from affecting the accuracy of the measurements being made.

Abstract: The disclosure is of a device for connecting togetheer two optical devices, and is primarily intended for quick connection and disconnection of two optical devices such as an endoscope and a viewing tube or two lenses.

Abstract: An electronic ferroelectric length measuring transducer and system for obtaining information and read-in of that information visually to determine the length of an image as well as means to determine if a target is moving. These actions are done very quickly and accurately by changing the polarization of a ferroelectric substrate. In addition, the information, once obtained, can be stored indefinitely without recourse to any external stimuli circuitry, until readout.

Abstract: In this disclosure is described apparatus for automatic pattern or object recognition in which objects or goods with optically recognizable patterns are optically scanned for the pattern by passing the objects in front of optical sensor means where the light reflected from the object is received by the sensor means. In this disclosure there is described in detail apparatus for identifying and sorting various types of returnable bottles such as soft drink bottles by scanning across the bottles, the light reflected from the bottle graphics providing a coded signal or signature representing the bottle type. The identification is accomplished by considering such signature features as number of peaks, largest gap, area under curve, summation of difference between consecutive data points and the ratio of the area to the difference summation. The values obtained for the features are then matched with known feature bounds to provide the identification.

Abstract: An instrument for measuring a dimension of an object is disclosed including a rotatable disc defining at least one translucent involute slit proceeding from a base circle centered at the center of rotation of the disc and a diaphragm mounted adjacent the disc and defining a linear slit arranged on a line tangent to the base circle. The intersection of the involute slit and the diaphragm slit forms a translucent overlap zone, and an image of the object is projected onto the disc or the diaphragm in the region of the diaphragm slit oriented such that the dimension to be measured is parallel to the diaphragm slit.

Abstract: Various vacuum ultraviolet monochromators embodying a rotatable diffraction grating and fixed entrance and exit slits, and working at a predetermined magnification are disclosed which provide improved optical performances by a correction of the odd terms of the wavefront aberration. In one group of instruments the fixed angle 2.theta. between the entrance and the exit beams is 90.degree. and the magnification 1. In another group, grazing incidence instruments are considered, 2.theta. being equal to 166.degree..

Abstract: A process and apparatus for the alignment of the image plane of an imaging system with the interception plane of the image utilizing a measuring mark reproduced by at least two partial pupils of the imaging system. The two imaging beams associated with the partial pupils are distinguishable from one another and at least one partial pupil is moved over the full pupil of the imaging system. A minimum movement of the image of the measuring mark corresponds to alignment of the image and interception planes.

Abstract: The temperature compensated positioning device consists of a stationary member, a movable member, a compensating material, and support material between each member. Each member is attached to two surfaces which must be held in a precise dimensional relationship with respect to each other automatically over a wide temperature range.

Abstract: A portable microfilm viewer for viewing a microfilm contained in a cassette. The viewer includes a housing with a lens system mounted therein. The cassette is removably received on a film transport mechanism which both supports and drives the film. A source of rotary motion is fixedly mounted on the housing and a bidirectional engaging device couples the rotary output to the film transport means for selectively transporting the film of the cassette in either of two directions across the lens system. The source of rotary motion can be a manual wheel or a motor device. A counter can be included for determining the film frame being viewed and for setting a desired film frame to be viewed, whereby the device will automatically stop when the desired film frame is in view. In an embodiment of the invention the microfilm viewer can also accommodate microfiche cards which can be viewed through the same lens system.

Abstract: An apparatus for automatic diagnosis of cells comprises a microscope, a scanning stage on the microscope, a sample carrier used to feed a sample to the scanning stage automatically, an automatic focussing mechanism, a detector assembly for detecting the light absorbance of the sample, and computation means. The computation means controls the operation of the components mentioned and automatically performs the processing of data obtained from the detector assembly, whereby the overall operation from the supply of cells to the diagnostic determination thereof is fully automated.

Abstract: An improved objective for a microscope, particularly clinical specular microscopes for the observation of cornea endothelium cells, comprises a housing having first and second tubular lens holders slidably disposed therein. The second tubular lens holder is slidably and telescopically disposed within the first tubular lens holder. The lens holders are spring loaded which allows them to recede under tension into the housing when the object being viewed presses against the exterior of the first lens holder. This helps to protect the subject when viewing the cornea endothelium in vivo. The holders return to their original position upon removal of the object. A focusing mechanism is provided which incrementally moves the second tubular lens holder, thereby focusing the objective lenses contained therein, no matter what the position of the first lens holder is, thereby facilitating examination of the cornea.

Abstract: An electro-optical switching apparatus which comprises at least an input photo-emitter circuit which lights up a switching matrix comprising a plurality of switching elements selected with two pluralities of crossed connections. Under the control of switching signals one of these elements turns on and allows the light to pass through. An image of this switching matrix is formed by a lens onto a matrix of photo-receiver circuits and the light transmitted through the turned on switching element induces in one of said photo-receiver circuits a transmitted switched signal.

Abstract: A display system using the dispersive Faraday coefficient of a magnetic screen to obtain a color display from white light is disclosed. A beam of energy is directed upon a magnetic screen while concurrently an intensity modulated magnetic field is directed normal to the surface of the magnetic screen. The combination of the heating effect of the energy beam and the magnetic orienting effect of the intensity modulated magnetic field established localized areas of differing magnetic characteristics over the planar surface of the magnetic screen. Subsequently, a polarized beam of white light that floods the magnetic screen is, for each of several wave lengths, differently rotated upon passing through each of the areas of differing magnetic characteristics in the magnetic screen. The beamlets that are formed by the so-differently rotated areas of the polarized white light beam are then passed through an uncrossed analyzer, which beamlets appear as a multicolored projection upon the magnetic screen.

Abstract: To determine a dimension of an object, two emitted beams whose axes define a known angle are directed by means of a deflector onto points of the object related to the dimension to be determined so that when one beam falls on the first of two points defining the dimension the other beam falls on the second point. Light rays reflected by the two points are received as two beams by means of a receiver. The angle of incidence of the emitted beam is measured with respect to a direction. The angles made respectively by the axes of the two received beams with the axes of the emitted beams are measured. The dimension is calculated from the angles.