520 results about "Waveguide mode" patented technology

A multiband waveguide reflector antenna feed comprises waveguide feeds in a concentric architecture. A waveguide feed is located in the center and coaxial waveguide feeds are disposed around the center feed. The waveguide feeds may be all-metallic with the center feed operating in a TE11 mode and the coaxial feeds operating in a coaxial TE11 mode. The waveguide feeds may have electromagnetic band gap (EBG) surfaces on waveguide surfaces. The center waveguide feed may have an EBG outer conductor surface and operate in a circular waveguide TEM mode. The coaxial waveguide feeds may have EBG inner and outer conductors and operate in a circular waveguide TEM mode. The coaxial feeds may have EBG inner conductors and near perfect electrical conductor (PEC) outer conductors and operate in a circular waveguide-like TE11 mode or may comprise EBG outer conductors and PEC inner conductors and operate in a quasi-TEM waveguide mode.

A dual polarised wave-guide notch antenna array is disclosed. The device comprises a feed section (1) having at least two input transmission lines, a feed / wave-guide interface (5) providing an aperture for transferring a radio frequency electromagnetic wave between the feed section (1) and a wave-guide mode in a wave-guide section (3) having ridges. The wave-guide section transfers energy between the feed / wave-guide interface and a tapered notch section (7), thereby gradually adjusting a created electromagnetic field towards free space conditions.

An optical waveguide mode transformer has a substrate supporting a high refractive index core layer surrounded by lower refractive index cladding. The core layer includes a wide input waveguide section to accept a multimode, including a fundamental mode, light input. The input waveguide section is coupled to a narrow output waveguide section by a tapered region having a taper length enabling adiabatic transfer of the fundamental mode of the multimode light from the wide input waveguide section to the output waveguide section while suppressing(stripping) other modes of the multimode light input. The narrow output waveguide section supports a single mode light output comprising said fundamental mode. The core layer is contoured to include a localized upstanding ridge intermediate opposite lateral sides of the core layer. The output waveguide section includes a portion having a real index step between the core layer and cladding layers, and advantageously is functional to output a light beam having similar vertical and horizontal divergences.

In an epitaxial structure of a solid state lighting system, electrical current injection into the active layer is used to excite the photon emission. The present invention employs a unique waveguide layer in the epitaxial structure for trapping the light generated by the active layer in the fundamental waveguide mode. Multiple photonic crystal regions with different characteristics located either outside or inside one or more current injection regions extract photons from the waveguide layer(s). The present invention creates solid state lighting with high optical output and high power efficiency.

Methods and systems for determining a geophysical position of an object in an underwater channel are provided. Acoustic signals from at least two sources are received by a receiver of the object. The acoustic signals have a frequency corresponding to at least one waveguide mode associated with the underwater channel, where the acoustic signals are transmitted at predetermined transmission times. An arrival time for the at least one waveguide mode is determined from the received signals, based on the predetermined transmission times. The geophysical position is determined based on the arrival time and a modal group velocity for the at least one waveguide mode.

The UV, deep UV and / or far UV (ultraviolet) filter transmission spectrum of an MPSi spectral filter is optimized by introducing at least one layer of substantially transparent dielectric material on the pore walls. Such a layer will modify strongly the spectral dependences of the leaky waveguide loss coefficients through constructive and / or destructive interference of the leaky waveguide mode inside the layer. Increased blocking of unwanted wavelengths is obtained by applying a metal layer to one or both of the principal surfaces of the filter normal to the pore directions. The resulting filters are stable, do not degrade over time and exposure to UV irradiation, and offer superior transmittance for use as bandpass filters. Such filters are useful for a wide variety of applications including but not limited to spectroscopy and biomedical analysis systems.

Analyzing interactions between vias in multilayered electronic packages that include at least two spaced-apart conducting planes, and multiple vias that connect signal traces on different layers. Voltages at active via ports are represented as magnetic ring current sources, which generate electromagnetic modes inside the plane structure. Substantial electromagnetic coupling between vias occurs. A full-wave solution of multiple scattering among cylindrical vias in planar waveguides is derived using Foldy-Lax equations. By using the equivalence principle, the coupling is decomposed into interior and exterior problems. For the interior problem, the dyadic Green's function is expressed in terms of vector cylindrical waves and waveguide modes. The Foldy-Lax equations for multiple scattering among the cylindrical vias are applied, and waveguide modes are decoupled in the Foldy-Lax equations. The scattering matrix of coupling among vias is then calculated for use in determining signal reflection, transmission, and / or coupling in the electronics package.

The new single mode circuit (SMC) architecture is invented for photonic integrated circuits (PIC). This architecture allows using multimode waveguides or structures to construct a single mode operated PIC. The multimode sections used in such SMC based PIC possess strong lateral confinement so that the PIC can have high circuit density and high optical performance at the same time. A parallel mode converter structure is also invented here. Based on this parallel mode converter, a low loss optical splitter can be constructed for high index contrast waveguide system.

An optical device is disclosed which includes a single-mode waveguide (700) which supports a first optical mode in a first region and a second optical mode in a second region. The waveguide includes a guiding layer (703) having at least one wing (750) extended outwardly from the guiding layer (703). The guiding layer (703) may desirably have a rib waveguide (706, 707) cross sectional shape at the wings. The wings (750) decrease in width along the length of the guiding layer to convert a rib waveguide mode at the wings to a channel waveguide mode.

In an epitaxial structure of a solid state lighting system, electrical current injection into the active layer is used to excite the photon emission. The present invention employs a unique waveguide layer in the epitaxial structure for trapping the light generated by the active layer in the fundamental waveguide mode. Multiple photonic crystal regions located either outside or inside one or more current injection regions extract photons from the waveguide layer(s). This novel design optimizes the interplay of electrical pumping, radiation and optical extraction to increase the optical output to several times that of conventional LEDs. A transparent and conductive ITO layer is added to the surface of an epitaxial structure to reduce the interface reflection in addition to functioning as a current spreading layer. The present invention creates solid state lighting with high optical output and high power efficiency.

The optical sensor of the present invention detects both the existence and concentration of substances by changing from light leakage mode to wave guide mode when the sensor is exposed to the substances to be detected. The changes in the mode results in a large change in optical output. This change is measured and the substance is identified and / or measured with high sensitivity.The change in light leakage mode to wave guide mode of the sensor is possible by having a clad material around the core material, with the clad material decreasing in the index of refraction when exposed to the substance to be detected. When the index of refraction of the clad becomes less than that of the core material, the sensor changes from the light leakage mode and operates in the wave guide mode. Changes in light intensity output from the sensor is measured over time, and correlated to the substance to be detected.

A method and system for waveguide mode filters are disclosed and may include processing optical signals of a fundamental mode and higher-order modes by filtering the higher-order modes in rib waveguides in a photonic chip. The higher-order modes may be filtered utilizing doped regions and / or patterns in one or more slab sections in the rib waveguides. The patterns may be periodic or aperiodic along the rib waveguides. The higher-order modes may be filtered utilizing varying widths of slab sections, or doped, patterned, and / or salicided ridges on the slab sections in the rib waveguides. The higher-order modes may be attenuated by scattering and / or absorbing the modes. The chip may comprise a CMOS photonic chip.

A system for coupling teraherz (THz) radiation to a coaxial waveguide comprises an antenna that generates THz radiation having a mode that matches the mode of the waveguide. The antenna may comprise a pair of concentric electrodes, at least one of which may be affixed to or formed by one end of the waveguide. The radiation may have wavelengths between approximately 30 μm and 3 mm. The waveguide may comprise an inner core and an outer wall defining an annular region. A terahertz sensor system may comprise a terahertz antenna comprising first and second concentric electrodes, means for generating a field across the trodes and means for triggering the emission of terahertz radiation, a first waveguide having first and second ends, said first end being coupled to said antenna so as to receive at least a portion of said terahertz radiation, and a sensor for detecting said terahertz radiation.

The invention relates to a small and low-voltage operable dielectric waveguide device. First and second electrode are embedded in a dielectric part and are formed to be thinner than a skin depth for a frequency of electromagnetic wave propagating along a first dielectric part included in the dielectric part. Thereby, even if the first and second electrodes are arranged to be in contact with the first dielectric part, the propagating electromagnetic wave can transmit the first and second electrodes, and therefore the electromagnetic wave can propagate without being cut off and there is no influence on waveguide modes of the electromagnetic wave. Further, in a state where a transmission loss due to the embedded of the electrode is suppressed, an electric field with large electric field strength can be applied to the first dielectric part by the first and second electrodes, and a small and low-voltage operable dielectric waveguide device can be achieved.

A waveguide-mode (WM) coupler having a plurality of single-mode fibers, each optically coupled to a different respective waveguide mode of a multimode fiber. The coupling optics employed by the WM coupler are scalable and include reflective fiber-tip coatings, polarization beam splitters, phase masks, and quarter-wave plates configured to overlap and / or separate the optical beams corresponding to different waveguide modes of the multimode fiber in a manner that does not cause a significant increase in the optical insertion losses with an increase in the number of optical channels in the WM coupler.

A radar level gauge (RLG) is provided for determining a filling level of a filling material contained in a container by transmitting and receiving elliptically or circularly polarized waves. The RLG comprises: a feeding circuitry for feeding and receiving two essentially orthogonal elliptically polarized waveguide modes, one of the modes for transmission and another mode for reception; an antenna for transmitting the waveguide modes towards the filling material and for receiving reflected signals; and a waveguide to provide signals between said feeding circuitry and the antenna. Further, the feeding circuitry comprises: a microwave generating unit (TX); a microwave receiving unit (RX); at least three feeding probes being at least partly exposed to the interior of the waveguide; and a coupling circuitry for transferring and feeding signals between each feeding probe and the microwave generating unit and / or the microwave receiving unit. At least the coupling circuitry and the feeding probes are implemented on a common printed circuit board (PCB), and the printed circuit board is arranged transversely over the waveguide.

A light emitting device (LED) employs one or more conductive multilayer reflector (CMR) structures. Each CMR is located between the light emitting region and a metal electrical contact region, thereby acting as low-loss, high-reflectivity region that masks the lossy metal contact regions away from the trapped waveguide modes. Improved optical light extraction via an upper surface is thereby achieved and a vertical conduction path is provided for current spreading in the device. In an example vertical, flip-chip type device, a CMR is employed between the metal bottom contact and the p-GaN flip chip layer. A complete light emitting module comprises the LED and encapsulant layers with a phosphor. Also provided is a method of manufacture of the LED and the module.

The present invention relates to a radar level gauge (1) comprising an antenna (2), a tank sealing (3), an electronics unit (4) and a waveguide feed (5) between the electronics unit (4) and the antenna (2). The waveguide (5) is essentially straight and has a 90°-symmetric cross section and is further arranged to accommodate two essentially orthogonal waveguide modes. The waveguide (5) further has a length (l) below two times the range resolution of said radar level gauge (1). The present invention further relates to a method for improved radar level gauging using a radar level gauge (1) as above.

In an optical substrate (1), a concave-convex structure (12) including a plurality of independent convex portions (131 to 134) and concave portions (14) provided between the convex portions (131 to 134) is provided in a surface. The average interval Pave between the adjacent convex portions (131 to 134) in the concave-convex structure (12) satisfies 50 nm≦Pave≦1500 nm, and the convex portion (133) having a convex portion height hn satisfying 0.6 h≧hn≧0 h for the average convex portion height Have is present with a probability Z satisfying 1 / 10000≦Z≦1 / 5. When the optical substrate (1) is used in a semiconductor light-emitting element, dislocations in a semiconductor layer are dispersed to reduce the dislocation density, and thus internal quantum efficiency IQE is improved, and a waveguide mode is removed by light scattering and thus the light the extraction efficiency LEE is increased, with the result that the efficiency of light emission of the semiconductor light-emitting element is enhanced.

A feed horn and systems and methods of making and using the feed horn are presented. Exemplary feed horns include a first portion comprising a dual mode geometry and a second portion comprising an axial corrugation geometry. The feed horn may operate simultaneously in a plurality of separate frequency bands (e.g., from about 18.3 GHz to about 20.2 GHz and from about 29.1 GHz to about 30.0 GHz) and a plurality of separate waveguide modes (e.g., TE11, TM11 or HE11 modes); simultaneously operating over two bandwidth segments of at least 1900 MHz that are separated by at least 5000 MHz. The feed horn may have a short axial length (e.g. less than 4 wavelengths at 18.3 GHz), and it may be configured to operate in a prime fed offset reflector antenna system. In addition, the feed horn may be formed as a single piece via a single casting pull.

A gas detection system includes a light detector, a pump laser with spectral emission between UV and IR wavelengths and structured to generate a laser beam, a hollow waveguide structured to receive a sample gas, the hollow waveguide having a bandwidth sufficient to transmit the laser beam and Stokes Raman photons scattered by the sample gas, and an optical system. The optical system is structured to: (i) direct the laser beam into the hollow waveguide such that it propagates in the hollow waveguide in one or more low-order low-loss waveguide modes, and (ii) direct Raman signals generated within the hollow waveguide in response to the laser beam interacting with the sample gas toward the light detector, the Raman signal including the Stokes Raman photons.

An optical device is disclosed which includes a single-mode waveguide (700) which supports a first optical mode in a first region and a second optical mode in a second region. The waveguide includes a guiding layer (703) having at least one wing (750) extended outwardly from the guiding layer (703). The guiding layer (703) may desirably have a rib waveguide (706, 707) cross sectional shape at the wings. The wings (750) decrease in width along the length of the guiding layer to convert a rib waveguide mode at the wings to a channel waveguide mode.

Proposed is a light-emitting apparatus 200,300,400, comprising a semiconductor light emitting device 220,320,420 and a transparent ceramic body 230,330,430 comprising a wavelength converting material positioned in light receiving relationship to the semiconductor device. The light-emitting apparatus is characterized in that the side surfaces 233,333,433 of the ceramic body 230,330,430 are at an oblique angle 234,334,434 relative its bottom surface 231,331,431. This is especially advantageous to unlock the wave-guide modes inside the body 230,330,430. Consequently the total flux emitted from the light-emitting apparatus 200,300,400 can be enhanced considerably. Alternatively, the brightness of the top surface 232,332,432 of the ceramic body 230,330,430 can be enhanced considerably.