Abstract: A device for determining the profile of a surface is disclosed. It comprises a beam arranged in a rotating plane about an axis of rotation, forming on the surface a light spot and scanning a sector of that plane. A detection system whose detection axis is situated in that plane cuts the beam near the surface and a system for measuring the angle formed by the axis of detection and the beam during the scanning when the light spot is situated on the detection axis is utilized.

Abstract: A spectrofluorometer providing wavelength correction by means of an arbitrary function generator driven by a wavelength scanning element of the spectrofluorometer. The arbitrary function generator may be driven by the emission scanning monochromator to derive a wavelength-dependent voltage signal which is combined with the measure photomultiplier output to thereby provide a base-line compensated resultant output signal. Alternatively, the arbitrary function generator may be driven by the excitation scanning monochromator to derive a wavelength-dependent voltage signal which is combined with the output of a reference photomultiplier tube receiving part of the output of the excitation monochromator to derive an excitation-corrected reference signal which is in turn combined with the measure photomultiplier tube output signal to thereby provide an energy-corrected resultant output signal.

Abstract: An electroluminescent semiconductor diode having a homogeneous monocrystalline semiconductor substrate providing a first zone on which an epitaxial layer has been formed providing a second zone. This second zone has a forbidden-band-width which changes steadily with increasing distance from the first zone. This second zone possesses a junction between a sub-zone having the properties of a "direct semiconductor" and a sub-zone having the properties of a so-called "indirect semiconductor" which lies parallel to the boundary between the first zone and the second zone and also parallel to the pn-junction of the diode. The pn-junction of the diode is located in the second zone and particularly in the sub-zone have the properties of an "indirect semiconductor" but at such a short distance from the junction of the two sub-zones that the major part of the charge carriers injected from the pn-junction in the direction towards the sub-zone having the properties of a direct semiconductor pass to this latter sub-zone.

Abstract: An automatic x-ray film loader is provided with film transports for moving the film to or from an exposure station that automatically correct improperly aligned sheets of film. The speed of at least one of the transports is automatically adjusted so that sheets are transferred from one transport to another smoothly and evenly. A simplified system for clamping the sheets of film between two intensifier plates and for moving one of these plates so that sheets of film can be fed to or moved away from the plates is also provided.

Abstract: A photosensitive surface is enclosed behind a wall formed with a vertically open slit which forms with the surface a vertical angle of 80.degree.. This slit is open about 3.degree. and is displaced horizontally past the surface through at least 150.degree. so as to let parallel rays of sunlight fall onto this surface and suppress diffuse nonparallel ground light. The wall can be carried on a support also carrying the photosensitive surface, e.g. a photoresistor, photocell, or photodiode, which is used to control an awning, roller blinds, or the like.

Abstract: An automatic information searching arrangement for searching desired image information from a record web having image information and searching marks placed thereon. The present invention provides scanning device which incorporates therein a light source and an image pickup tube or a flying spot cathode-ray tube and a photoelectric converter to convert it into an electric signal in time series. The blip zone in the record web is projected by the scanning device to convert it into an electric signal in time series whereby a desired information frame may automatically be searched. The information searching device comprises a unit for feeding a record web, a unit for scanning searching marks, a unit for forming one count signal from a plurality of mark signals generated from the scanning unit, and a conrol unit for generating a signal for controlling the feed of the record web. The record web may accurately be positioned by the arrangement of the present invention.

Abstract: An elongated workpiece having unfinished side surfaces inclined laterally downwardly and outwardly from a finished top surface is scanned to produce signals denoting location of the longitudinal edges of the top surface at numerous points along them. A swinging plane mirror defines an elongated scanning zone which extends across the workpiece and is translated all along it. The workpiece is alternately illuminated from opposite sides at a low angle of incidence to its top surface to shadow first one side surface, then the other. Scanning lengthwise along the scanning zone is synchronized with translation of that zone and with lighting alternation. A preferred apparatus is disclosed for establishing a reference line on the workpiece to which scanning data can be related.

Abstract: A method for use in object examination involves the subdivision of a lens field of view into a succession of cells, the encoding of such cell succession and the making of a record of radiant energy reflected into the lens field of view from the object and issuing from the cell succession.

Abstract: Secondary radiation in a non-linear crystal is produced by irradiating the crystal with a coherent primary radiation, to produce a coherent phase-adapted secondary radiation whose frequency is doubled with respect to the frequency of the primary radiation. In a modification of the method, two different sources of primary radiation are used, in such a way that the secondary radiation in the crystal is equal to the sum or the difference of the frequencies of the primary radiation sources. In apparatus for carrying out the method, the crystal to be irradiated is mounted in a swinging or tiltable carrier. The emerging radiation is partially reflected onto a pair of photoelectric detectors, the output of which controls a servomotor to vary the degree of tilt of the crystal. In a second embodiment, there are two crystals tilting in opposite directions. In a third embodiment of the apparatus, two separate sources of primary radiation serve to irradiate a single crystal.

Abstract: This invention relates to intrusion detection devices, and in one embodiment includes an array of infra-red detectors with associated means for selectively increasing the number of scan zones which may be monitored by the same detector array, by providing an optical system with reflectors and/or lenses having a multiplicity of facets set at selected angles to direct primary impulses received from portions of the entire scanned field sequentially to the detector array.

Abstract: An electrochromic display device having transparent front electrodes on a substrate, said front electrodes being coated with electrochromic material having different oxidation states for displaying optical patterns, a back electrode on a parallel substrate also coated with electrochromic material, a thin porous separator between the substrates, a liquid electrolyte contacting the electrochromic layers, said electrolyte being saturated with electrochromic materials in each of the oxidation states to reduce the degradation of the electrochromic layers as they pass through each of the oxidation states. The saturating materials are tungsten trioxide, hydrogen tungsten oxide, and tungsten dioxide in the electrochromic display described.

Abstract: A burner control system has a field device and control logic for providing a control signal to change the state of the field device. A comparator that compares signals from field and the control logic comprises translation circuitry that is arranged to produce an output pulse train signal in response to a corresponding input pulse train signal, and power supply circuitry that has two logic inputs. The power supply circuitry supplies power to the translation circuitry only in response to a proper comparison between a field signal applied to one logic input and the control signal applied to the other logic input.

Abstract: A photodiode detector comprises a substrate on which a plurality of detector sections are formed, in series. Reverse bias is applied to the separate sections, the bias more negative for each section from the input end. The absorption bandwidth for each section can vary and the bandwidth of a section can be variable.

Abstract: The average aperture width in a small area of an apertured member, such as a shadow mask for a cathode ray tube, is determined by passing a beam of substantially monochromatic light through an area of the member to form an interference pattern, detecting the intensities of at least two light fringes of the interference pattern, generating electrical signals which are representative of the detected intensities and then deriving the average width of apertures in the lit area of the members from the generated signals.

Abstract: In a shaft angle encoder, an optical system translates the shaft angular displacement into a difference of two optical path lengths and that difference is measured by interferometry. Light from a monochromatic source is split and both the transmitted and reflected beams are passed along separate paths through an optical component that moves angularly with the shaft and varies the lengths of the separate paths differentially according to the shaft angular displacement. The transmitted and reflected beams are then recombined and the interference fringes in the recombined beam sensed by a detector.

Abstract: In an apparatus, an imaging system, at least one optically effective grating and a photoelectric receiver system are employed for determining the relative position of the plane of maximum amplitude of a spatial frequency component in the image of an object. The imaging system produces from light fluxes emanating from the object and traversing different regions of the entrance pupil of the imaging system an image of the object in a first, a second and a third intermediate image plane. The focussing screen mounted in the first plane is used for subjectively observing and focussing the object as well as for transmitting light fluxes to the optically effective grating which defines a given spatial frequency component and which is mounted at least in the vicinity of the second intermediate image plane for commonly modulating and splitting the light fluxes. The photoelectric receiver system generates therefrom electrical output signals used in devices for indicating and adjusting the sharp focussing of the object.

Abstract: A method and apparatus are provided to continuously monitor and measure the average size of individual foam cells contained in a foam structure, such as polystyrene foam for example, as it is being fabricated. Such an arrangement permits the prompt adjustment of process conditions and/or the concentration of nucleating agents in the extrusion system in the event the foam cell size deviates from a preselected norm. The method comprises illuminating the surface of a foam sheet, receiving and collecting at least a portion of the light which is diffused and reflected from the foam sheet with a detector photocell, electrically measuring the amount of light energy received by the photocell and converting such measurements into a cell size measurement.

Abstract: A controlled system for focussing a read-out light beam onto a moving track carrying information, comprising: a focussing objective lens for forming a periodic motion along its optical axis, under the action of a pilot device; a comparator comparing the pilot signal with the envelope of an electrical read-out signal, the comparator thus producing a focussing error signal, and means for applying said signal to the focussing objective lens for correction purposes.

Abstract: Method and means for determining the particle size distribution in a flow of granular material in the particle size range of 1 .mu.m to several millimeters by introducing into a constant velocity stream of a carrier medium, preferably transversely thereof, a stream of the material to be analyzed, said introduction being effected at a constant velocity within a measuring time period, and the velocities of said two streams being so coordinated as to cause the individual particle size classes to be carried along separate particle paths in a fan-shaped pattern while being subjected to an electromagnetic radiation, and determining the particle quantities corresponding to the individual particle size classes in the fan-shaped stream of material from the extinction or absorption of said electromagnetic radiation.

Abstract: Apparatus for measuring angular displacement of an object in which an alternating potential source is applied to the electrodes of a light source, such as a gaseous discharge light, resulting in alternating illuminations in the medium, e.g., gas, about the respective electrodes, which are detected by photodetector means. The light source and the photodetector means are mounted such that the distances between the photodetector and the respective electrodes vary proportionately with any rotation of the object whose angular displacement is being monitored. The output signals from the photodetector means are separated and compared and, in response thereto, a signal is generated indicative of the angular displacement of the object.