Reflector (antenna)

About: Reflector (antenna) is a research topic. Over the lifetime, 28730 publications have been published within this topic receiving 212618 citations.

Semiconductor light emitting device

Abstract: PURPOSE:To improve the conversion factor and reduce the size of a semiconductor light emitting device by a method wherein a distributed black reflector which reflects a laser beam to a laser beam emitting part side is provided on a semiconductor substrate common with the laser beam emitting part and in the region where an optical waveguide is formed CONSTITUTION:An optical waveguide 36 which is made of nonlinear optical material and guides a laser beam and converts a part of the laser beam into a 2nd harmonic beam is provided and integarated on a common substrate 20 and on the side of the end surface of the semiconductor laser 22 of a double- hetero structure 24 through which the laser beam enters and comes out A distributed black reflector 38 which reflects the laser beam to the double-hetero structure 24 side is provided in the region where the optical waveguide 36 is formed so as to constitute a resonator of a semiconductor light emitting device for the emitted laser beam and to transmit the 2nd harmonic beam With this constitution, a single mode oscillation can be realized and the conversion factor can be improved and, moreover, the size of the semiconductor light emitting device can be reduced

Code sensor with multi-faceted reflector for sensing plural image distances

Abstract: A bar code scanner having a lens, a reflector, a sensor, and a detection unit. The lens is arranged to focus an image of a bar code to be scanned along an image path. The reflector is angled obliquely to the image path so as to reflect images at an angle to the image path. The reflector has reflector surface shaped so as to provide a plurality of reflected images of the scanned bar code, with one of the reflected image being an in-focus image and a remainder of the reflected images being out-of-focus images. The sensor is in the image path and simultaneously senses the plurality of reflected images and provides a sensor output signal corresponding to the sensed images. The detection unit is coupled to the sensor and decodes the sensor output signal and provides a bar code output signal that corresponds to the scanned bar code.

Design of Engineered Reflectors for Radar Cross Section Modification

Abstract: A technique is proposed for the design of engineered reflectors consisting of doubly periodic arrays printed on thin grounded dielectric substrates that reflect an incoming wave from a given incoming direction to a predetermined outgoing direction. The proposed technique is based on a combination of Floquet theory for propagation in periodic structures and reflect-array principles. A flat surface designed to reflect a TE polarized wave incident at 45° back in the direction of the impinging signal at 14.7 GHz is employed as an example. By means of full-wave simulations, it is demonstrated that the monostatic RCS of a finite reflector is comparable with the specular RCS of a metallic mirror of the same dimensions. It is further shown that comparably high monostatic RCS values are obtained for angles of incidence in the 30°-60° range, which are frequency dependent and thus open opportunities for target localization. A prototype array is fabricated and experimentally tested for validation. The proposed solution can be used to modify the radar cross section of a target. Other potential applications are also discussed.

Design of an optical element forming an axial line segment for efficient LED lighting systems

Abstract: An LED optical element is proposed as an alternative to cold-cathode fluorescent lamps. The optical element generates two symmetric uniformly illuminated line segments on the diffuse reflector. The illuminated segments then act as secondary linear light sources. The calculation of the optical element is reduced to the integration of the system of two explicit ordinary differential equations. The results of the simulation of an illumination system module consisting of a set of optical elements generating a set of line segments on the surface of the diffuse reflector are presented. The elements are located directly on the surface of the reflector. The simulation results demonstrate the uniform illumination of a rectangular area at a distance of 30–40 mm from the light source plane. The lighting efficiency of the designed system exceeds 83%.

Automotive radar using a metamaterial lens

Abstract: An example apparatus comprises an electromagnetic source, such as an antenna, a metamaterial lens, and a reflector The antenna is located proximate the metamaterial lens, for example supported by the metamaterial lens, and the antenna is operable to generate radiation when the antenna is energized The reflector is positioned so as to reflect the radiation through the metamaterial lens The reflector may have a generally concave reflective surface, for example having a parabolic or spherical cross-section The metamaterial lens may have an area similar to that of the aperture of the reflector In some examples, the antenna is located proximate a focal point of the reflector, so that a generally parallel beam is obtained after reflection from the reflector