Showing papers on "Reflector (antenna) published in 1971"

Toward a unified theory of reflector mapping

Abstract: Schemes for seismic mapping of reflectors in the presence of an arbitrary velocity model, dipping and curved reflectors, diffractions, ghosts, surface elevation variations, and multiple reflections are reviewed and reduced to a single formula involving up and downgoing waves. The mapping formula may be implemented without undue complexity by means of difference approximations to the relativistic Schroedinger equation.

Phased array system

Abstract: A phased array antenna utilizing a parasitic reflector in which the area of the array of radiating elements is smaller than the area of the reflector. The reflector has a concave surface which, in one embodiment of the invention, is a hyperbola of revolution for collimating the rays of radiation incident thereupon from the array of radiating elements. The surface of the reflector is particularly adapted to permit the generation of a set of phase shift command signals by means of a novel ray tracing program to provide a collimated beam which may be scanned in response to the phase shift imparted through radiation radiated by the radiating elements. A narrow beam of radiation is obtained by virtue of the relatively large sized reflector even though the dimensions of the array of radiating elements are relatively small.

Simple model of corner reflector phenomena

Abstract: The principle of cube corner reflector operation is simple, and a careful examination of operational details is valuable in promoting an understanding of the potentials and limitations in reflector use. This paper describes an easily visualized model by which these principles may be understood. From this model, simple procedures may be derived for determining the effective aperture area variation of conventional corner reflector configurations. The variation of the effective aperture of some conventional configurations is then computed. The effects of angular errors in the alignment of the reflecting surfaces are also modeled.

Catoptric anastigmatic afocal optical system

Abstract: A CATOPTRIC ANASTIGMATIC AFOCAL OPTICAL SYSTEM IS FORMED BY TWO CONCAVE PARABOLOIDAL REFLECTORS OF DIFFERENT POWERS AND A CONVEX HYPERBOLOIDAL REFLECTOR EACH ADAPTED TO RECEIVE AND FOCUS RADIANT ENERGY. A PARABOLOIDAL REFLECTOR AND THE HYPERBOLOIDAL REFLECTOR HAVE THEIR AXES OPTICALLY COINCIDENT AND ARE POSITIONED WITH THE REAL FOCUS OF THIS PARABOLOIDAL REFLECTOR AT THE VIRTUAL FOCUS OF THE HYPERBOLOIDAL REFLECTOR. THE AXIS OF THE OTHER PARABOLOIDAL REFLECTOR IS OPTICALLY COINCIDENT WITH THE AXIS OF THE HYPERBOLOIDAL REFLECTOR AND ITS REAL FOCUS IS COINCIDENT WITH THE REAL FOCUS OF THE COMBINATION OF THE FIRST PARABOLOIDAL REFLECTOR AND THE HYPERBOLOIDALL REFLECTOR. BY HAVING THE SUM OF THE POWERS OF ALL THE REFLECTOR. BY HAVING THE SUM ORDER ABERRATIONS EXCEPT DISTORTION ARE ZERO, IF THE SUM IS NOT ZERO, THIRD ORDER ABERRATIONS, OTHER THAN FIELD CURVATURE AND DISTORTION, ARE ZERO.

Reflector and cooling means therefor

Abstract: Printing apparatus utilizing lamps generating ultraviolet light to cure solvent-free ink by photopolymerization is provided with lamp reflectors having shutters to permit the lamps to remain energized while the printed work conveyor is stopped or is moving at a slow rate. A plurality of such lamps, each with an individual shutter, are arranged in parallel rows extending transverse to direction of movement of the work. As the shutters are closed, lamp voltage is reduced to a standby point where the lamps remain fired. Air is circulated at the same time behind the lamp reflector for cooling of the latter without appreciably cooling the lamp. Each reflector is a sheet of non-oxidizing metal mounted in the concave portion of a structurally strong housing. End reflectors prevent end scattering of the lampradiated energy and shield the lamp sockets from the heating effects of this energy. The lamp sockets are repositionable with respect to the reflector so that the arc thereof may be positioned generally along the focus line of the reflector for different positions of the focus line with respect to earth.

Automatic door-opening system using an acoustic object detection system

Abstract: An object detection system is disclosed which makes use of an acoustic transducer for generating compressional waves in the air and detecting return pulses from an object lying within the detection zone. A transducer mounting system includes a transducer slug mounted for generating acoustic waves from both ends of the slug. The antenna system includes a reflector housing adapted to accommodate variable surfaces for controlling the energy pattern. Details of the electronic circuitry associated with the transducer mounting system and a door opening system are disclosed.

Covering device for skylights

Abstract: A covering device for a skylight in a flat roof including a frame mounted in the skylight opening and having horizontally disposed reflector panels that are inclined relative to the roof. The frame is rotatable and can be tilted or the panels can be tilted to follow the relative movement of the sun.

Reflector assembly for reflecting the vapors of high temperature volatile materials

Abstract: A vapor reflector assembly disposed in a vapor deposition chamber comprises a thin, fluorinated resin film coated onto a support body and means to heat said film to an elevated temperature.

Behavior of Gunn diode oscillator with a moving reflector as a self-excited mixer and a load variation detector

Abstract: Analyses are carried out by using a simplified model of the dynamic current-voltage characteristic of the Gunn diode oscillator. Experiments have been also carried out. For the self-excited mixers, an external signal was injected into the oscillator instead of the signal reflected by the reflector. For the effects of the moving reflector upon the oscillation frequency and dc current were investigated in the static condition.

Underwater guidance method and apparatus

Abstract: Equipment, such as a drill string, is guided from an ocean platform to a submarine wellhead by an acoustical energy system including a corner reflector at the wellhead, a pulse transmitter and associated transponder near the lower end of the drill string, and a receiver at the platform. The transmitter, operating at a first frequency, transmits pulses to the reflector, which reflects the pulses to the transponder. Energy is sent by the transponder to the platform receiver at a second frequency. When the transmitter and the receiver are in line with the wellhead reflector, energy at the first frequency is reflected directly to the receiver to produce a "go" signal.

Lamp and reflector assembly

Abstract: A high-intensity arc lamp having anode and cathode stems extending in opposite directions from the bulb, is positioned in a reflector. The anode stem extends within a tapered hollow collar at the rear of the reflector, and the lamp is attached to the reflector by means of cement at the remote ends of the anode stem and hollow collar, whereby the hollow collar provides a heat-confining space around the anode stem for controlling the temperature and reducing the likelihood of thermal-stress cracking of the anode stem. A specially shaped connector within the reflector provides electrical connection to the cathode lead.

Device for toasting and/or grilling

Abstract: A device for heat-treating, such as toasting and/or grilling, foodstuff, has a housing, a foodstuff supporting grid, a heating element, and a metal foil reflector that is supported in an easily exchangeable manner with relation to a reflector support.

Reflector arrangement for attenuating selected components of spectral radiation

Abstract: A REFLECTOR ARRANGEMENT FOR GASEOUS DISCHARGE LAMPS IS DESCRIBED, HAVING REFLECTING SURFACES REPRESENTING RESONATE OPTICAL CAVITIES AT SELECTED WAVELENGTH FOR ATTENUATING EXCESSIVE PEAKS OF SPECTRAL COMPONENTS CHARACTERISTIC OF THE PRIMARY RADIATION SOURCE.

Rotating reflector level rod

Abstract: The present invention provides an apparatus and a related method of carrying out leveling survey operations (differential and trigonometric), and is distinguished more particularly by the application of a Rotating Reflector Level Rod which in conjunction with a laser distance measuring instrumentation combines the means of obtaining the required distance measurements to establish the elevations of remote ground points.

Network for pulling a microwave generator to the frequency of its resonant load

Abstract: A resonant microwave load, such as a microwave linear accelerator section, is coupled to a magnetron oscillator via the intermediary of a circulator. Power reflected from the resonant load is reflected to the circulator and thence to a wave absorptive load. A composite wave reflector and variable phase shifter is provided between the absorptive load and the circulator for reflecting a portion of the power reflected from the resonant load to the magnetron oscillator for pulling the frequency of the oscillator to the frequency of the resonant load. The composite wave reflector and variable phase shifter includes a wave reflective member carried from a support rod passing through the wall of a rectangular waveguide. Rotation of the support rod causes the wave reflective member to move in a generally axial direction within the waveguide for adjusting the phase of the reflected wave such as to pull the frequency of the magnetron to the frequency of the resonant load.

Apparatus for automatically directing and maintaining a beam of electromagnetic radiation relative to earth horizontal

Abstract: Apparatus for maintaining the direction of a beam of electromagnetic radiation relative to earth horizontal comprising an optical reflector, a pendulum connected to the reflector and a mounting frame supporting said reflector and said pendulum by independent gimbal suspension whereby said reflector moves responsive to pendulum motion through one-half the rotational angle of said pendulum, correcting an optical path in accordance with changes in the position of the pendulum relative to the mounting frame. Apparatus units utilizing coherent light beams are a specific embodiment.

Isochrons For A Three-dimensional Seismic System

Abstract: The three-dimensional seismic system discussed by Walton (1970-1971) explores seismically a column of earth extending from the surface to deep reflectors. Interpretation of data from the system is done directly from displays on a grid of the detected signals. In this paper we derive expressions for the patterns expected on three-dimensional system displays when energy returning to the detectors consists of reflections from planes, diffractions from faults or point scatterers, reflections from reflectors of arbitrary shape, refractions and reflected-refractions from planes, or direct or surface waves. Examples of typical patterns are shown. Our derivations are limited to ray geometry and shed no light on amplitude variations. Also, an average velocity from the surface to a reflector, refractor, or diffractor is assumed.

Singly-curved reflector for use in high-gain antennas

Abstract: A furlable antenna particularly suited for use aboard spacecraft. The antenna is characterized by an improved reflector plate conforming to a frusto-conical configuration combined with a point-source feed and a secondary reflector having a reflective surface conforming to a figure of revolution generated by rotating a segment of a parabola about an axis parallel the ray path of the intermediate rays, whereby the antenna can be stowed in a furled configuration without substantially reducing its efficiency.

New Techniques for Implementing Microwave Biological-Exposure Systems

Abstract: In investigating the biological effects of microwave radiation, one of the most vexing problems is that of generating an essentially uniform plane wave with sufficient power density for illuminating biological samples. This paper describes three illumination systems: a focused prolate spheroid, an absorber-lined horn, and a compact range. The focused prolate spheroid has two foci: a waveguide feed is located at one, and the biological sample is located at the other. Large power densities can be obtained over an area of about one square wavelength. The absorber-limed horn acts as a small source within an anechoic chamber; such an illumination system reduces errors due to interaction with the biological sample. The compact range employs a reflector and feed system to generate a plane wave across a large aperture; such a range is an attractive device for illuminating large volumes. All three systems can be implemented in a limited space without an anechoic chamber. Experimental data obtained from model systems are presented.

Apparatus for the control of traveling constructional implements

Abstract: An apparatus for controlling travelling constructional implement using guide planes, comprising a transmitter and receiver device, having at least one transmitter and one receiver connected with the implement, and a reflector fixed to the ground, the reflector having the properties of a plane mirror adapted to reflect radiation between the transmitter and the receiver means.

Shrouded offset parabolic reflector antenna

Abstract: A reflector antenna has a reflector with an offset feed. The reflector is partially encompassed by a shroud which may be reflecting, absorbing, or both, to energy radiated by the feed. The shroud is effective to block energy radiated by the feed that would otherwise spill over the edge of the reflector, only along a portion of the edge less than its entirety.

Gregorian antenna with ring focus

Abstract: A Gregorian antenna system has the usual main reflector, subreflector, a first feed for illuminating the main reflector from the virtual focus via the subreflector, and a second feed for directly illuminating the main reflector from a prime focus. The second feed is shaped, and is positioned relative to the subreflector, to create a ring focus for energy reflected from the subreflector to the main reflector, and the main reflector is shaped to have the ring focus as its prime focus.

Square lite projector using prismatic lens

Abstract: A reflector and lens projecting assembly is adapted to project a rectangular or square pattern of light from a conventional circular reflector. A prismatic lens having four 90 DEG segments is positioned in front of the reflector and directs the light from the reflector into four mutually over-lapping segments in which radii of the unmodified pattern from the reflector form the boundaries of the square or rectangular pattern as modified by the lens. Embodiments are shown using light modifying prisms in which the thick portions of the prism are at the periphery of the lens and in which the thick portions of the prism are at the center of the lens.

Combined scan and track antennas

Abstract: Combined scan and track antennas are disclosed, each comprising a reflector and a feed thereto in which the track reflector and its feed and the feed to the scan reflector are all fixed with respect to each other and the scan reflector rolls in such a manner that a line through the center of the spherical feed antenna and the fixed feed point therefor always is perpendicular to a point on the surface of the spherical reflector through which it extends.

Projection light source and optical system

Abstract: Disclosed is a lamp and reflector system designed to produce maximum energy through an aperture at a pre-determined intensity distribution across an aperture, particularly the film gate aperture of a movie projection system. The invention involves a gaseous discharge lamp having an arc or light source region of varying radiance with the radiance at one electrode substantially higher than the other and a modified eliptical reflector generally axially aligned with respect to the discharge lamp and with the primary focus of the reflector along the axis of the lamp but with the secondary focus at the plane of the aperture on a line forming an angle Delta with the axis of the lamp. Also disclosed is means for determining the optimum mirror or reflector length S in order to produce the maximum energy at a given intensity distribution across the film gate aperture of a projector system. The arc length, radiance distribution, the angle Delta , the mirror or reflector length S and the aperture dimensions are correlated for a reasonable projection f/number in a manner that the image of the brightest portion of the arc is superimposed upon the extremities of the aperture from all points on segment S and the images of the arc at the aperture from various points on the ellipse segment form a family of images with the average size equal to approximately 3/4 of the diagonal dimension. In achieving this type of image, the highest radiance portion of the arc is placed at the first focus of the mirror.

Reflector for marking driveways and the like

Abstract: The reflector for marking driveways and the like is adapted to be resiliently clamped to a rod which can be inserted into the ground. One or more reflectors can be supported on the rod at various angles and reflect the lights of passing cars to mark, for example, the entrance to a driveway. Each reflector is constructed of a circular molded plastic frame to hold the reflecting plastic and has internal resilient members projecting inwardly from the frame which cooperate to securely clamp the reflector to the supporting rod which passes through aligned holes in the frame and a passage between the springlike internal members. Each reflector at one end has an octagonally shaped embossment on the frame around one of the holes in the frame, and a second embossment around the aligned hole at the opposite side of the frame which has an octagonally shaped inset. Thus, the embossment of one reflector can be seated in the inset embossment of an adjacent reflector to locate a respective reflector at four different angular positions on the supporting rod relative to an adjacent reflector.