Reflector (antenna)

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

Reflector providing particularly high reflectance in an intended viewing angle and reflection type liquid crystal display device using the same

Abstract: The present invention provides a reflector having a light-diffusing property which suppresses inter-object reflection over a wide angle, and giving particularly high reflectance in an intended range of viewing angle; and to provide a reflection type liquid crystal display device using the same. The reflector includes a plurality of light-reflective concave portions. Each of the concave portions is formed so that an inclination angle (an angle between a plane tangential to a point on a concave surface and the surface of the base material) is maximum on a side portion of the curved surface, and so that the direction of the side portion having the maximum inclination angle is on a far side from a view point of an observer. Moreover, the reflector includes many concave portions formed on a reflector surface, an inner surface of each of the concave portions including a peripheral curved surface and a bottom curved surface that are continuously connected to each other, the peripheral curved surface being a part of a first sphere having a first radius, the bottom curved surface being a part of a second sphere having a second radius different from the first radius, and the bottom curved surface being located within the peripheral curved surface, wherein the first radius is smaller than the second radius, and a normal line extending from a center of the first sphere to the reflector surface and a normal line extending from a center of the second sphere to the reflector surface are not collinear. Further, the reflection type liquid crystal display device is provided with the reflector.

Self-monitoring semiconductor laser device

Abstract: The present invention is a semiconductor laser having an integral photodiode and/or modulator. The integrated structure comprises a quantum well active region sandwiched between a pair of distributed Bragg reflector stacks for emitting laser light transverse to the planes of growth. An intrinsic layer and a doped semiconductor layer are disposed on one of the reflector stacks for forming, in combination with the outer layer of the stack, a photodiode in the path of emitted light. The diode can be used either to monitor the laser power or to modulate the laser output. The device is particularly suited for fabrication and testing in large arrays and, in addition, has the advantages of a circular, low divergence optical output, inherently single mode operation, and a high two-dimensional packing density.

Compact micro-concentrator for photovoltaic cells

Abstract: A reflector array comprises a plurality of partial parabolic reflectors arranged in rows and columns with each reflector directing radiation to a receiver or from a transmitter located at the focus of the reflector. In a compact photovoltaic cell arrangement, each cell is shielded from direct radiation by the adjacent reflector. The reflectors can be formed as one unit with reflective material or with the reflecting surfaces coated with aluminum, silver, or other suitable reflecting material. A secondary reflector can be positioned at the focus of a reflector for directing radiation to a receiver or from a transmitter located at a more accessible location in the array.

Imaging and suppressing near-receiver scattered surface waves

Abstract: When traveling through a complex overburden, upcoming seismic body waves can be disturbed by scattering from local heterogeneities. Currently, surface-consistent static and amplitude corrections correct for rapid variations in arrival times and amplitudes of a reflector, but these methods impose strong assumptions on the near-surface model. Observations on synthetic and laboratory experiments of near-surface scattering with densely sampled data suggest that removing noise from near-receiver scattering requires multichannel approaches rather than single-channel, near-surface corrections. In this paper we develop a wavefield-based imaging method to suppress surface waves scattered directly beneath the receivers. Using an integral-equation formulation, we account for near-surface heterogeneities by a surface impedance function. This impedance function is used to model scattered surface waves, excited by upcoming wavefronts. The final step in our algorithm is to subtract the scattered surface waves. We succes...

Head-up display device

Abstract: A head-up display device having an excellent appearance, which has a simple structure and an excellent design upon both nonuse and use, is provided A cover having a shape equivalent to that of an aperture formed on an upper surface of a housing is attached on an upper surface of a retractable reflector The cover slides on the upper surface of the reflector cooperating with a retractable motion of the reflector, thereby performing the opening and closing action of the aperture When the reflector takes its falling-down posture, the reflector and its rotation shaft can be shielded from an eye range and the number of the parting lines can be reduced