Abstract: The fingers of a multistrip coupler for surface acoustic waves are weighted in at least one, i.e., input or output, track so as to match a predetermined energy profile for that track. In one embodiment, the weighting is achieved by apodizing the fingers of the multistrip coupler. In another embodiment, each finger is formed in a variable-amplitude zig-zag pattern. The invention is particularly advantageous when used to transversely couple surface acoustic wave resonators.

Abstract: A surface acoustic wave device comprises a piezoelectric substrate which carries input and output transducers for launching and receiving surface acoustic waves on the substrate, one or more reflective arrays for reflecting surface acoustic waves between the two transducers, wherein at least one array comprises numerous spaced reflecting elements of varying lengths arranged in two sets, one set being angled to reflect surface acoustic wave in one direction while the other set is angled to reflect surface acoustic wave in another direction. Varying the lengths of the reflecting elements provides weighting of signals passing through the device. Additionally pulse compression and expansion may be arranged with or without frequency dispersion.

Abstract: An electronic circuit for starting and operating gaseous discharge lamps. A DC input is connected to a time-ratio control (TRC) circuit which includes a regulating transistor, a sensing resistor and a coasting inductor connected in series. A flyback diode is connected to the inductor for providing a discharge path for the inductor. The TRC circuit serves to ballast the gaseous discharge lamp. An inverter is connected to the TRC circuit for driving the lamp with square waves. A starting circuit is provided and is connected to one of the lamp electrodes for starting the lamp. A transient protection circuit is provided for the inverter to shunt transients back to the input. A TRC drive and control circuit is connected to the TRC regulating transistor and sensing resistor for controlling the regulating transistor.

Abstract: A device for use in producing a scanning beam of radiation comprises a rotor member carrying two optical wave guides arranged so as to direct light along the rotary axis of the rotor member, then radially outwardly to pass from one wave guide to the other, then radially inwardly and finally along the said rotary axis again.When the device is adapted for investigating liquid samples, a turntable, carrying a number of vials containing liquid samples at spaced locations around its periphery, is rotated in indexing fashion and, during each dwell period of the turntable, the rotor member is rotated so that the circularly scanning beam of light leaving the first mentioned wave guide scans each of the vials in turn at least once.

Abstract: Fiber optic ribbons are attached to the output facets of laser dice which are positioned in thin slotted anodised aluminum plates between indium coated copper plates. A plurality of such plates provide a stack which is compression bonded with the opposite laser faces extending into the adjoining indium coatings. The sides are lapped and clamped to a heat sink.

Abstract: A light-responsive electric switch is composed on the one hand by an electronic circuit constituted, in the case of direct-current supply, by a voltage divider comprising a fixed resistor and a variable resistor forming the photo-conductive cell, by four transistors which are blocked or rendered conductive according to the illumination of the photo-conductive cell, by a change-over switch transmitting the voltage to another transistor into the collector circuit of which a motor is connected, and on the other hand by an electro-mechanical device constituted by a bistable trigger circuit controlling the motor, by a step-down gearing meshing with a pinion fixed on the shaft of this motor, by cams fast with the shaft of the final pinion of the step-down gearing and by one or more contacts which close or interrupt one or more lighting circuits.

Abstract: A system for determining a transversal position of any defect in a traveling sheet material having a defect detector and at least one scanning detector, in which the transversal position of the defect in the sheet material is determined by the coincidence between a defect signal from the defect detector and an output signal from the scanning detector.

Abstract: A device for viewing microreproductions on a transparent film has a lens and a film supporting means which has a pair of frame members adapted to clamp the film therebetween through magnetic attraction of one of the frame members to the other, either the lens or the film support being slidably movable with respect to the other for focusing purposes.

Abstract: A light beam target for light beam shooting and apparatus employing it are disclosed. The light beam target has a light transparent target plate, stripe-like first and second X- and Y-axis photoelectric conversion elements and a compensating photoelectric conversion element disposed on the back of the target plate. When a light beam is projected onto the target plate, the first and second X- and Y-axis photoelectric conversion elements provide first and second X- and Y-axis electric signals corresponding to the position of the center of the light beam on the target plate. The apparatus using such light beam target has a circuit for producing X- and Y-axis light beam center indicating signals indicative of the position of the center of the light beam on the target plate based on the first and second X- and Y-axis electric signals and a device for displaying on an indicator plate the position of the center of the light beam on the target plate.

Abstract: An electrical signal ratioing circuit for a source delivering an electric analog pulse signal sequence having compensating means for removing the effects of background influences, such as amplifier signal offsets and extraneous illumination, and integrating means eliminating the effect of line voltage variations and changes in optical and electrical system gains on the ratios so produced.

Abstract: A compact offset Cassegrainian antenna having a paraboloidal main reflector and a convex subreflector brings microwave beams to a focus. A small flat reflector placed in one of the beams at the focus deflects it for interception by a concave reflector and horn. Another beam passing by the flat reflector is intercepted by a second concave reflector and horn. The flat reflector is smaller than a focally located horn, allowing more closely-spaced beams to be accommodated. The flat reflector may be replaced by a curved reflector, a prism, or a microwave lens. Another flat reflector is added for each additional beam. Polarized beams are accommodated by adding a polarization screen.

Abstract: This invention relates to a system for automatic focus adjustment of an optical system particularly adapted for use in a photographic camera which utilizes non-linear resistance versus illumination response characteristics which are prominent in photoconductive cells such as cadmium sulfide and cadmium selenide cells. In one embodiment, a pair of photoconductive cells, one of which has a photoconductive surface having elongated side portions which contact the electrodes along the length of the elongated side portions and another cell which has an elongated photoconductive surface and shortened end portions and which contact the electrodes only at the shortened end portions, are arranged so that portions of an image-forming light beam entering through an objective of the camera are directed to the photoconductive surfaces on which similar real images of an object are formed.

Abstract: A light emitting diode is driven by an input signal and electromagnetically coupled to a photodiode. The photodiode is connected to a high impedance load across which is obtained a signal linearly related to but electrically isolated from the input signal.

Abstract: An optical modulation system and frequency doubler utilizes an organo-substituted carborane cell sandwiched between a pair of crossed polarizers. Light passing through the cell is rotated an amount determined by an electrical control signal applied across the cell. Hence the amount of light passing through the system is modulated by the control signal. When the cell is modulated by an AC control signal, light modulation occurs at twice the AC control signal frequency since the cell has two possible orientations which permit maximum light transfer. The modulated light is directed upon an electro-optical transducer which produces an electrical output proportional to the intensity of the light impinging thereupon.

Abstract: A smoke detector device for detecting the density of smoke in a smoke passage, comprised of a light source, a photocell, a means for focusing a beam of light emitted from the light source across the smoke passage onto the photocell, and a circuit means coupled to the photocell and arranged to produce a signal when the smoke density in the smoke passage is above a specific smoke density level. The means for focusing the beam of light is comprised of a first lens and a second lens; the first lens is in optical communication with the light emitted from the light source and is constructed and positioned so as to focus the light across the smoke passage onto the second lens; the second lens is constructed and positioned so as to focus the light coming from the first lens onto the photocell. The smoke detector device may further have a first and second lens which are removable and a means for testing the signal.

Abstract: A light filtering system for improving the spectral output from fluorescent lamps. A filter placed within the lamp envelope between the phosphor coating and the arc discharge path between the lamp electrodes, absorbs mercury arc radiation in the visible range while passing arc radiation in the ultraviolet range to excite the phoshor coating and produce visible light emitted through the outer envelope.

Abstract: A digital transducer comprises a container having two disparate materials therein defining an interface, the interface being movable through the container responsive to a force, or forces, applied to one, or both, of the materials. A plurality of sensors are spaced along the container for sensing the interface, each of which is responsive to the presence of one of the materials. Means are included for suppressing the outputs of all of the sensing means responsive to the one material except that one sensing means which is responsive to the one material and nearest the interface.

Abstract: The method consists in causing objects to pass in front of a background having a distinctly different brightness, in aligning a collimator by means of a sighting telescope in a direction of observation such that the path of the objects intersects a line defining the direction of observation of the collimator, in eliminating light from all directions other than the direction of observation, in detecting the variation of light intensity corresponding to the passage of the object by means of an electrical signal which is delivered by a photoreceiver and is a function of the luminous flux picked up by the photo-receiver and in differentiating the signal with respect to time by means of an electronic circuit so as to obtain an output signal which is a function of the variations of luminous flux on the photoreceiver.

Abstract: The embodiment of the invention disclosed herein is directed to a magnifying lens structure adapted to receive a light from within a housing and transmit the light toward an object point of the lens to illuminate the area thereabout. The lens structure has two parallel strips of refractive surfaces on opposite sides of a magnifying lens. The light is transmitted into the transparent lens material and therethrough to the strips of refractive surfaces whereupon the light is directed to the area which surrounds the object point for better viewing of the area.

Abstract: In the measurement of angular position the phenomena of moire or watered configurations produced by a grating on a disc is used.