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: An object of the present invention is to provide a light-emitting device with a high output and a high efficiency by improving the efficiency for utilizing light emitted from a semiconductor light-emitting element. The inventive semiconductor light-emitting device comprises a package substrate, a sub-mount provided on the package substrate, a semiconductor light-emitting element provided on the sub-mount, and a reflector surrounding the sub-mount and the semiconductor light-emitting element, wherein the positions and sizes of the sub-mount, light-emitting element and reflector satisfy the following relationship (A) on a cross section perpendicular to the package substrate that passes through the center of the semiconductor light-emitting element, r - ls ≤ (hs - d) x (ls - lc) /hc --- (A) wherein r, ls and lc are distances from the drooping portion of the reflector, form the outer circumference of the sub-mount and from the outer circumference of the semiconductor light-emitting element to the center of the semiconductor light-emitting element, respectively, hs and d are heights of the sub-mount and of the drooping portion of the reflector, respectively, and hc is a height of the upper surface of the semiconductor light-emitting element from the upper surface of the sub-mount.

Transmissive optical imaging device with micromirror array

Abstract: We propose a new imaging optics called the Transmissive Mirror Device (TMD). It consists of numerous micromirrors placed perpendicular to the surface of a flat, thin metal plate. The micro-mirror array is implemented by the inner walls of minute square holes, which are densely pitted on the device. The basic mode of operation is based on two reflections by a pair of adjacent mutually perpendicular mirrors, i.e., a dihedral corner reflector. Although the principal of operation is based on reflection by mirrors, the device is also transmissive and deflects light. Since this imaging system forms a real image at a plane symmetric point, the depth of the 3D image is inverted. Its optical defects are low optical transmittance and stray light caused by non-reflected light and that reflected once. We manufactured the device experimentally with nano-precision machining technology and also evaluated it.

Glare-shielding type reflector

Abstract: This invention discloses a glare-shielding reflector which controls light reflectance electrically. The present invention provides a glare-shielding type reflector having a photosensor block which can detect an incident angle of a luminous flux to the reflector and a glare-shielding layer which is divided into plural units and driven individually. A glare-shielding layer formed on a front surface of a mirror is divided into plural units and only the specified glare-shielding units are automatically put into a glare-shielding state, according to the incident angle of the luminous flux to the mirror.

Encapsulated packaging for thin-film resonators and thin-film resonator-based filters having a piezoelectric resonator between two acoustic reflectors

Abstract: An acoustic reflector ( 48 ) is applied over a thin-film piezoelectric resonator ( 41, 61 ) which is supported on a semiconductor or semiconductor-compatible substrate ( 42, 62 ) of a microelectronic device ( 40, 60 ), enabling an encapsulant ( 49 ) to be applied over the reflector-covered resonator without acoustically damping the resonator. In one embodiment, alternating high and low acoustic impedance layers ( 51, 53 . . . 55 ) of one-quarter wavelength thicknesses constructively reflect the resonating wavelength to make an encapsulant in the form of an inexpensive plastic molding compound appear as a “clamping” surface to a resonator ( 41 ) peripherally supported over an opening ( 43 ) on a silicon substrate ( 42 ). In another embodiment, an encapsulant- and reflector-covered resonator ( 61 ) is mechanically supported above a second reflector ( 68 ) which eliminates the need for peripheral support, making substrate ( 68 ) also appear as a clamping surface. The invention enables low cost plastic packaging of resonators and associated circuitry on a single monolithic structure. A radio frequency transceiver front-end application is given as an exemplary implementation.