Showing papers on "Reflector (antenna) published in 1978"

Vehicle having side-rear surveillance radar with antenna reflector assembled with rearview mirror

Abstract: A vehicle comprising a radar system for surveillance of a side and rear area and a rearview mirror unit mounted on the outside of the vehicle body. The antenna reflector of the radar has a light-transmissible structure and is received in the frame of the rearview mirror unit so as to be spaced rearwards from the mirror and to protrude sidewise from the outline of the vehicle body. This antenna arrangement is most appropriate to side-rear lookout and is favorable to the appearance of the vehicle.

Double reflector antenna with feed horn protection

Abstract: A double reflector antenna mounted on a terrestrial mount with Azimuth and elevation shafts in which a primary field radiating and detecting horn is mounted within a housing behind a central opening of the main reflector dish so as to radiate and receive energy from a sub-reflector mounted at the focal point of the main reflector dish and such that the lead supplying energy to and from the horn can be very short and the horn can be substantially shielded from snow and rain.

Ideal light concentrators with reflector gaps

Abstract: A cylindrical or trough-like radiant energy concentration and collection device is provided. The device includes an energy absorber, a glazing enveloping the absorber and a reflective wall. The ideal contour of the reflective wall is determined with reference to a virtual absorber and not the actual absorber cross section.

Ideal flux concentrators with reflector gaps

Abstract: A design for a solar concentrator is presented that provides maximum flux concentration on the physical absorber.(AIP)

A new dielectric facet reflector for semiconductor lasers

Abstract: Described in this letter is a new dielectric reflector designed for injection laser facets which consists of alternating quarter‐wavelength layers of Al2O3 and Si. The reflectivity for six layers can be made ≳0.98 over a wavelength range from ∼0.7 to ≳2 μm. By choosing the appropriate number of quarter‐wavelength layers and the final layer thickness the reflectivity can be varied between 0.01 and 0.98. Finally, both Si and Al2O3 are impervious to the chemical cleaning and wetting agents and solders used during the mounting of (AlGa)As cw injection lasers.

Ellipsoid-conic radiation collector and method

Abstract: Disclosed is a radiation collector apparatus and method primarily for counting and analyzing a flow of dilute particulate material, such as blood cells, sperm cells and the like, through the use of light detection. The radiation collector apparatus comprises a reflector chamber having an ellipsoidal reflector surface with a pair of elipsoidal foci defining a first focus, f 11 , and second focus, f 12 , and a second reflector surface with a primary focus, f 21 , positioned at the same point as focus f 12 , and a secondary focus, f 22 . The second reflector surface has the configuration of one of the conic sections of revolution. In operation the radiation collector apparatus is provided with an intensifed beam of light and a stream of particulate material aligned to intersect the intensifed beam of light at focus f 11 . Detectable light signals, after two reflections, are received in a focused beam by a photosensitive detector.

Solar tracking concentrator

Abstract: A solar tracking point concentrator for a solar energy system comprises a light weight reflector in the shape of a paraboloid dish having a rim angle of approximately 109°, whereby the center of gravity of the reflector mass is coincident with the focal point of the paraboloid. The reflector is supported on a light weight pipe pedestal assembly and controllably driven by a light weight control-drive means so as to be angularly adjustable in both elevation and azimuth to track the sun and efficiently continuously reflect the sun's rays to a heat receiver disposed at the focal point of the paraboloid preferably in a fixed position. The reflector is mounted for controlled movement to effect such angular adjustments about horizontal and vertical axes which intersect at the focal point of the reflector paraboloid. The 109° paraboloid rim angle provides a paraboloid reflector that inherently has its center of gravity essentially coincident with its focal point. This arrangement provides an essentially balanced mounting of the paraboloid reflector without requiring counterbalancing means. Therefore, the paraboloid reflector may be supported by a light weight pipe pedestal assembly and driven by light weight control-drive means, such as linear stepping motors which are controlled by electronic pulses generated by light weight microprocessors.

Reflector for solar collectors

Abstract: Reflector for solar collectors consisting of a mirror glass plate (23). To minimize the absorbed radiation energy through the glass plate, a thin glass plate is provided, the plate strength is below that required for a self-supporting glass plate glass thickness. This glass plate is adhesively bonded with its mirrored side on a supporting body (22), and in particular a honeycomb support body.

Installation for utilizing solar energy with wavelength selective reflector

Abstract: By means of a plurality of reflectors, solar rays are focused on at least one operative region in which there is disposed a solar-radiation absorbent body which is thereby heated and which transmits the absorbed heat to a liquid or vaporous heat carrier. By fabricating the reflectors of a material permeable to the short-wave portion of the solar radiation and reflective of the long-wave portion of the solar radiation, the ground area shaded by the reflectors can be utilized for other purposes, especially for growing plants.

Front loading projection unit

Abstract: An improved projection unit which permits removal of the unit's lamp from the front, concave portion of the unit's reflector. A first retention member is used to maintain the lamp in pre-established alignment within the reflector and a second retention member, e.g. resilient clamp, is movably oriented on the reflector's neck portion to secure the first retention member in a first position and release it in a second.

Automated warehouse vehicle position determining system

Abstract: A system for determining the position of vehicles in an automated warehouse of the type utilizing transfer vehicles and robot vehicles is disclosed. The position determining system includes a photo-electric sensor flexibly coupled to a robot vehicle, which sensor is responsive to its alignment with a pallet stored in the warehouse. The system further includes a photo-electric reflector retaining bracket mounted adjacent to an aisle in the warehouse, the bracket supporting a number of reflectors arranged in a pattern containing information identifying the aisle. A photo-electric transceiver supported by a mounting bracket is connected to a transfer vehicle and is arranged to provide an output signal related to the pattern of the reflectors when the transceiver is in alignment with the reflectors whereby the transfer vehicle is apprised of its location in the warehouse. The system also includes an activation reflector having a smaller reflective expanse than the pattern forming reflectors, the activation reflector being used to activate the pattern responsive portion of the transceiver. The system further includes a pair of fine alignment photo-electric transceivers which serve to finely align the transfer vehicle by requiring the vehicle to search for a position in which the two fine alignment transceivers are simultaneously aligned with a reflector supported by the retaining bracket. This abstract is not to be taken either as a complete exposition or as a limitation of the present invention, however, the full nature and extent of the invention being discernible only by reference to and from the entire disclosure.

Dielectric reflector for selective wavelength reflection

Abstract: There is disclosed a dielectric reflector for selective wavelength reflection which comprises an alternately deposited series of thin films of silicon and silicon dioxide layers respectively arranged in an alternating sequence of at least one layer of each type of material. This reflector is suitable for use on the reflecting electrode of a liquid crystal video display panel fabricated on a semiconductor substrate. The use of the dielectric reflector in place of other types of reflectors increases the available reflectivity and permits a preselected color or wavelength to be preferentially reflected. The polysilicon layer of the dielectric reflector is doped with p-type or n-type impurities such as boron or phosphorus to make this layer electrically conductive.

Optical performance of absorber-reflector combinations for photothermal solar energy conversion

Abstract: For a number of absorber-reflector combinations the reflectance spectrum as well as the figure of merit a/e has been computed numerically in order to find an optimum set of parameters. Values of a/e in excess of 20 result for an absorber consisting of 0.5 μm Ge on a silver reflector, overlaid by 2.0 μm Si carrying a four-layer antirereflection sequence in which the refractive index varies from 2.79 to 1.43. To maximize the optical acceptance angle the antireflection coatings must vary the refractive index in a graded profile from the value of index of silicon to the one of air.

Dual frequency band directional antenna system

Abstract: A dual frequency band directional antenna or system in the form of a cavity reflector antenna mechanically combined and radiation-coupled with a loop of approximately the same shape and periphery as the rim edge of the cavity reflector, which loop is arranged outside and in front of, and in close proximity and parallel to the cavity rim edge, and, when properly energized, acts for the lower frequency band as a loop radiator with preselected field polarization, whereby the entire cavity structure serves two purposes by acting simultaneously as reflector for the higher frequency band cavity reflector antenna and for the lower frequency band, electrically separate loop radiator, with the radiation patterns of both sources being unidirectional over both frequency bands and with their radiation maxima directed into the center axis normal to the bottom plate of the cavity reflector structure.

Acoustic levitation and methods for manipulating levitated objects

Abstract: Objects are levitated in a sound system substantially free of reverberation and reflection by positioning a small reflector in the path of sound waves. Interference between the primary waves and reflected waves creates a localized zone of minimized energy closely adjacent to the reflector in which an object may be stably levitated. The energy well thus produced is not dependent upon distance from the sound source, and the levitated object may be moved in any direction by moving the reflector. A plurality of reflectors may be employed to manipulate and combine levitated materials, and improvements in the processing of levitated objects are also achieved.

All plastic headlamp

Abstract: A practical all plastic headlamp is disclosed comprising, for the lens and reflector, an engineering plastic having a heat distortion temperature in excess of 130° C.

Portable luminaire with fluorescent lantern

Abstract: A portable electric lamp structure having a housing, a substantially parabolic reflector mounted on the housing, an incandescent lamp positioned substantially at the focal part of said parabolic reflector, a self-contained direct-current electric power source positioned within the housing, and manual switch means for electrically connecting the power source to the incandescent lamp for energizing same. A curved reflector is disposed adjacent the outer free edge of the parabolic reflector and extends radially outwardly therefrom. A ringlike fluorescent lamp is positioned in front of the curved reflector in concentric relationship with the parabolic reflector, and an inverter is electrically connected to the fluorescent lamp for converting direct current to alternating current. The switch means is electrically connected between the power source and the inverter.

Ellipsoid radiation collector apparatus and method

Abstract: Disclosed is a radiation collector apparatus and method primarily for counting and analyzing a flow of dilute particulate material, such as blood cells, sperm cells and the like, through the use of radiation detection. The radiation collector apparatus comprises a reflector chamber having an ellipsoidal reflector surface with a pair of ellipsoidal foci defining a primary focus and secondary focus. A window is formed in the ellipsoidal reflector surface and is centered on a symmetry axis defined by the primary and secondary foci. In operation the radiation collector apparatus is provided with an intensified beam of radiation and a stream of particulate material aligned to intersect the intensified beam of radiation at one of the ellipsoidal foci. Detectable radiation, either directly or after one or more reflections, proceeds through the window in an organized beam for detection.

Solar refrigeration system

Abstract: A solar reflector defining a concave parabola of revolution having flared ends and a central saddle region collects solar energy which is reflected onto an arcuate reflector which in turn reflects the received energy to a solar energy absorbing device which converts the solar energy in thermal energy to operate a gas absorption refrigeration unit. The apparatus is maintained at all times perpendicular to the solar energy through the use of a thermally expandable fluid actuating system to compensate for the sun's seasonal declination.

Primary reflector for solar energy collection systems

Abstract: A fixed, linear, ground-based primary reflector having an extended curved sawtooth-contoured surface covered with a metalized polymeric reflecting material, reflects solar energy to a movably supported collector that is kept at the concentrated line focus of the reflector primary. The primary reflector may be constructed by a process utilizing well-known freeway paving machinery.

Ultrasonic sector scanner

Abstract: An ultrasonic sector scanner for producing a sector scan in an object to be examined in which one or more ultrasonic transducers are positioned to direct ultrasonic waves toward the surface of one or more movable reflectors. The movable reflectors traverse an arcuate path with respect to a stationary reflector which is positioned to receive the ultrasonic waves scanning the surface of the stationary reflector from each of the movable reflectors and converge such waves at a point in front of the stationary reflector.

Ultrasonic focusing system

Abstract: A system for dynamically focusing ultrasonic waves consisting of a housing filled with a liquid media, an ultrasonic transducer, a reflector, and a control device. The ultrasonic transducer, located within the housing, emits ultrasonic waves and detects echoes of the ultrasonic waves as they return from the object being scanned. The reflector is also located within the housing and is positioned so as to intercept and redirect the ultrasonic waves and the resulting echoes. The reflector consists of a flexible reflective membrane which is stretched across an air filled enclosure. The control device is located adjacent the housing and consists of a member adapted to variably compress the liquid media contained in the housing so as to provide pressure variations to the reflective membrane. These pressure variations periodically deform the reflective membrane so that the ultrasonic waves from the transducer are reflected to converge at a point a preselected distance beyond the reflector and the echoes returning from a preselected range within the scanned object are in focus approximately at the ultrasonic transducer surface.

Statistical analysis of Bragg reflectors

Abstract: The effects on reflectivity of a statistical variation in the thickness of layers in a multilayered Bragg reflector are studied. Analytic expressions are obtained for 〈ρ〉 and 〈ρρ*〉, the expected value of the reflection and reflectivity coefficients as a function of σ, the standard deviation in layer thickness. These expressions are then compared with values obtained using a computer routine which "builds" a reflector with the desired parameters and σ value, and then calculates the reflection. The results of the computer experiment are presented in the form of p(ρρ*), the probability distribution function of a statistical Bragg reflector. Finally, simple phenomenological expressions are presented for the reflectivity probability distribution.

Reflector with air pressure means

Abstract: This invention relates to large reflectors in particular those used for antennas, solar mirrors and the like having a concave reflector surface The reflector comprises a membrane having a reflective surface, which membrane in its initial planar state is capable of being deformed in all directions in its plane The reflector is mounted in a gas-tight chamber as one wall thereof and a differential pressure is exerted across the membrane either by way of increased or reduced pressure applied to the chamber When deformed to concave shape, such deformation may be sufficient to cause permanent deformation of the membrane to its concave shape when it has been stretched beyond its elastic limit and plastic deformation has occurred The reflector may then be used removed from the gas-tight chamber and when so used is preferably backed with a rigid foam backing Alternatively, the differential pressure applied to the membrane may be insufficient to permanently deform the membrane to its concave shape and a rigid foam backing or the like applied thereto while it is in its deformed concave shape In this circumstance the rigid foam maintains the reflector in its deformed concave shape Still further, the differential pressure across the membrane whether sufficient to cause permanent deformation or not may be maintained during use of the reflector In this circumstance the gas-tight chamber becomes a supporting structure for the concave membrane and the differential pressure maintains the shape A rigid ring serves as the circumferential edge of the chamber and the deformed membrane is maintained in tension by the differential pressure

Multimode dual frequency antenna feed horn

Abstract: A prime focus multimode feed horn is used to illuminate a parabolic reflector such that the reflector-horn combination produces improved performance in the E-plane and H-plane of a principal aperture. A feed assembly which includes the multimode horn also has a hub assembly that is incorporated into the reflector with support structure, a boom, supporting interconnecting waveguides and the multimode dual frequency horn. Directly coupling the horn to the feed assembly is an orthomode generator connected to a receive waveguide and a transmit waveguide. The orthomode generator is assembled to a horn body waveguide that supports a horn aperture having a circular configured principal aperture surrounded by radially displaced circular rings forming concentric channels for modification of the E-plane receive pattern. Assembled into the horn aperture is an insert having opposed shoulders in the H-plane and opposed steps in the E-plane such that for an incoming plane wave the first zeros of the focal plane Bessel Function Distribution are coincident with the effective horn aperture. Also extending into the principal aperture in the H-plane are opposed matching buttons.

Surface roughness measuring apparatus

Abstract: A doppler radar of the type normally used to measure relative speed between a transmitter and a reflector is mounted so that its antenna is directed toward the surface to be measured. The radar is coupled to a means for de-emphasizing the doppler shift frequencies of the return signal associated with the speed of the vehicle and emphasizing the lower frequency components of the back scattered signal. The energy contained in these components provides an indication of the roughness of the surface which is in relative motion to the radar.

Yagi-type antennas and method

Abstract: This disclosure is concerned with compensating for unsymmetrical antenna receiving or transmitting patterns caused by unbalanced driven element feed, by compensatory unsymmetrical interaction with parasitic director and/or reflector elements.

Headlamp, particularly for motor vehicles

Abstract: This specification discloses a headlamp for motor vehicles and the like which includes a spacer or distance part between the front glass and the reflector. The distance part is formed as a mounting member carrying fasteners for mounting the headlamp unit in a body opening. The distance part is connected to the reflector by a pivotally movable ring assembly and the distance part carries adjustment means acting on the reflector. This headlamp design avoids gaps at the junction of the front glass and the body opening and offers the advantages of headlamps of the semi sealed beam type and headlamps with front glasses fixed to the body.

Three-dimensionally curved, knit wire electromagnetic wave reflector

Abstract: An electrically conducting, electromagnetic wave reflector comprises a knit wire reflecting surface consisting of two superimposed knitted wire meshes. The wire mesh reflector is impregnated with a transparent thermo-setting resin so that the metallic structure is no more than 3 mils from the outer surface of the reflector. The knitted wire mesh permits the fabric to be smoothly stretched over a three-dimensional surface of predetermined shape. The two wire meshes are staggered with respect to each other to reduce the effective size of the openings between the loops of the mesh. A reinforcing structure preferably consisting of two layers of glass cloth impregnated with a thermo-setting resin is utilized to provide a lightweight reflector substantially impervious to environmental corrosion. The resulting structure may be used as an antenna or reflector and is suitable for the microwave region such as the K band.