46results about How to "Absorption loss" patented technology

Electromagnetic radiation sources operating in the Terahertz (THz) region capable of overcoming the Manley-Rowe limits of known optical schemes by achieving phase matching between a THz wave and optical pulse in a nonlinear waveguide, or by achieving both phase and group velocity matching between a THz wave and optical pulse in a nonlinear waveguide to yield even higher efficiencies in converting optical power to the THz region.

An optoelectronic device includes a planar active element, a vertical waveguide surrounding the active element in the vertical direction, and a lateral waveguide comprising at least one active section and at least one filter section following each other in the longitudinal direction. At least part of the active element within the active section generates optical gain in response to above-threshold pumping. The broad lateral waveguide in the active section can localize multiple lateral optical modes. In the filter section, no lateral confinement is provided for the lateral optical modes. The device further comprises means to ensure low absorption loss in the filter section and, therefore, ensure high efficiency. In one embodiment low absorption loss is achieved by pumping of at least part of the active element within the filter section. In another embodiment, the active element has small overlap with the vertical optical modes.

According to the present invention, sufficient light trapping effect can be exhibited and series resistance can be kept small, by sequentially forming a silicon based low refractive index layer and a thin silicon based interface layer on a backside of a photoelectric conversion layer observed from a light incident side, and as a result a silicon based thin film solar cell may be provided efficiently and at low cost.

Semiconductor laser diodes, particularly high power AlGaAs-based ridge-waveguide laser diodes, are often used in opto-electronics as so-called pump lasers for fiber amplifiers in optical communication lines. To provide the desired high power output and stability of such a laser diode and avoid degradation during use, the present invention concerns an improved design of such a device, the improvement in particular significantly minimizing or avoiding (front) end section degradation of such a laser diode and significantly increasing long-term stability. This is achieved by separating the waveguide ridge into an active main ridge section (4) and at least one separate section (12) located at an end of the laser diode, which may be passive. The separation is provided by a trench or gap (10) in the waveguide ridge. The active waveguide section (4) is at least partly covered by the electrode (6) providing the carriers that does not extend to cover the separate ridge section (12), which thus remains essentially free of carriers injected through said electrode (6). There may be a plurality such separate ridge sections, e.g. two separate ridge sections (12, 212), one at each end of the laser diode, dividing the ridge waveguide into three ridge sections, an active main ridge section (4) in the center and a passive separate ridge section (12, 212) at either end. The trenches (10, 110) between the sections and/or the shape and size of the separate ridge section (s) (12, 212) may be adjusted to act as spatial mode filters.

The invention provides ultraviolet (UV) light-emitting diodes (LEDs). The UV LEDs can comprise abase layer including p-type SiC or p-type AlGaN, an active layer, and an n-AlGaN layer, wherein the active layer is disposed between the base layer and the n-AlGaN layer. In some embodiments, the absorption losses in p-SiC can be decreased or prevented by incorporating a conductive AlGaN Distributed Bragg Reflector (DBR) between the p-type SiC layer and the active layer. In some embodiments, the n-AlGaN layer can be textured to increase the extraction efficiency (EE). In some embodiments, the external quantum efficiency of the LEDs can be 20-30% or more.

A Mach-Zehnder interferometer type optical modulator includes first and third optical waveguides; input and output optical couplers; and a phase shifting section disposed between the input and output optical couplers. The phase shifting section includes first and second optical waveguide structures each including an n-type semiconductor section, a core layer and a cladding layer. The cladding layer of the first optical waveguide structure includes a first section disposed on the core layer, and second and third sections disposed on the first section. The second and third sections are juxtaposed to each other in a direction that intersects a waveguiding direction. The first and second sections are composed of a p-type semiconductor, and the third section is composed of an undoped semiconductor.

The invention relates to a daylight illumination apparatus. A daylight collector (3) collects daylight (4), which is guided to an illumination location to be illuminated along an optical path by a light guide (5), wherein the daylight is absorbed by the light guide. A photoluminescent material (6, 8) is arranged within the optical path and emits photoluminescent light that compensates for the absorption of the daylight by the light guide. Absorption losses of the daylight can therefore effectively be compensated, without necessarily needing, for example, an active compensation light source. This allows providing compensated day-light illumination in a technically relatively simple way.

The present invention is drawn to a composition and process for inhibiting hair from becoming frizzy when exposed to high and/or low humidity, the composition containing: (a) at least one fatty monoamine; (b) at least one nonionic surfactant; (c) at least one anionic silicone; (d) at least one water-insoluble material; (e) at least one cationic polymer; and (f) at least one film former, different from (e).

This invention intends to develop a technique for forming an interlayer with excellent optical characteristics and to provide a photoelectric conversion device having high conversion efficiency. To realize this purpose, a series connection through an intermediate layer is formed in the thin-film photoelectric conversion device of the invention, and the interlayer is a transparent oxide layer in its front surface and n pairs of layers stacked therebehind (n is an integer of 1 or more), wherein each of the pair of layers is a carbon layer and a transparent oxide layer stacked in this order. Film thicknesses of each layer are optimized to improve wavelength selectivity and stress resistance while keeping the series resistance.

An embodiment of the photoelectric conversion device is characterized in that; a transparent insulating substrate is located on the light incidence side, and a transparent conductive layer, at least one photoelectric conversion unit, a transparent electrode layer having electrical conductivity as typified by zinc oxide, a hard carbon layer having electrical conductivity as typified by diamond-like carbon, and a high reflecting electrode layer are stacked in this order on an opposite surface from a light incidence side of the transparent insulating substrate.

The present invention provides an electromagnetic wave resonator that is capable of showing surface wave resonance typically as outstanding plasmon resonance and can be manufactured industrially with excellent reproducibility and efficiency by combining currently available microprocessing technologies. The electromagnetic wave resonator of the present invention includes a first negative dielectric surface, a second negative dielectric surface and a positive dielectric thin film disposed between the first and the second negative dielectric surfaces. The positive dielectric thin film has an end face having an electromagnetic wave introduced therefrom. Intensity of the electromagnetic wave having a predetermined wavelength and being introduced from the end face is enhanced in the electromagnetic wave resonator due to resonance of a surface wave having an electric field component in a direction of film thickness of the positive dielectric thin film and without having a cut-off frequency.

A single mode optical waveguide which is lithographically formed and employs polymeric materials having low propagation loss. The optical waveguide has a substrate, a polymeric, buffer layer having an index of refraction nb disposed on a surface of the substrate, a patterned, light-transmissive core layer having an index of refraction nc disposed directly on a surface of the cladding layer, and an overcladding layer having an index of refraction no on a top surface of the core, side walls of the core, and exposed portions of the buffer layer, with nb<no<nc and DELTAn=nc-no.

In an X-ray imaging system, first and second grids are disposed between an X-ray source and an X-ray image detector, and produce fringe images. From the fringe images, phase change information of X-rays is obtained. The phase change information provides contrast for an X-ray image. The first and second grids have similar configuration. Each grid is constituted of a grid layer and a support member. The grid layer includes X-ray absorbing portions and X-ray transparent portions arranged alternately in one direction. Each X-ray transparent portion contains hollow space having air trapped therein, for the purpose of reducing an X-ray absorption loss.

An electrically pumped lateral emission electroluminescent device may include a slotted waveguide including a top silicon layer having a thickness between 150 nm and 300 nm and a refraction index associated therewith, and a bottom silicon layer having a thickness between 150 nm and 300 nm and a refraction index associated therewith. A core layer may include silicon oxide between the top and bottom layers and a thickness less than 70 nm. A core layer refraction index may be greater than each of the top and bottom layer refraction indices. A core layer portion may be in a direction of light propagation and may be doped with erbium, and may include silicon nanocrystals. A portion of each of the top and bottom layers may coincide with the core layer portion and may be doped so that the top and bottom layer portions are electrically conductive to define top and bottom plates.

The invention relates to a method and a device for analyzing a biological tissue, whereby a luminescence light of a luminescence substance is detected. The aim of the invention is to increase the precision and reliability of the analysis. To this end, a permutation symmetry imbalance is generated in the tissue by a magnetic field, the permutation symmetry imbalance is modified at a pre-determined location by a magnetic alternating field, and the luminescence light is detected according to the pre-determined location.

A rotary seal capable of joining a stationary member with a rotating member is provided, wherein the rotary seal comprises a body having a central hole therethrough, wherein said central hole has stepwise reducing diameter so as to form two part central hole, wherein front part of said central hole has higher inner diameter and rear part of said central hole has lower inner diameter, wherein said front part forms a seat with said rear part of said central hole, wherein said front part of said central hole is capable of accommodating at least one sealing member, and said sealing member is made to sit onto said seat by a screwing member, which when fixed onto body fits into front part of said central hole, and said rear part of said central hole is capable of accommodating connecting member of said stationary member. An apparatus comprising the rotary seal is also provided.

An apparatus for analyzing a measuring substance which is dissolved in a solvent, comprising a conduit (4) for transporting the dissolved measuring substance from a feed means (3) to a measuring location (12), wherein the feed means (3) is designed to optionally feed a solvent or dissolved measuring substance into the conduit (4), is characterized in that the conduit (4) is designed, at least partially, as a polycapillary area (9) which has N parallel connected capillaries (21a, 21b, 21c; 62a, 62b), such that the individual capillaries (21a, 21b, 21c; 62a, 62b) have identical flow times from the feed means (3) to the measuring location (12) and wherein N≧2. The apparatus improves the signal-to-noise ratio of the analysis.

The present invention relates to a laser device being formed of at least one VCSEL (15) with intracavity contacts. The VCSEL comprises a layer structure (18) with an active region (6) between a first DBR (4) and a second DBR (10), a first current-injection layer (5) of a first conductivity type between the first DBR (4) and the active region (6), and a second current-injection layer (8) of a second conductivity type between the second DBR (10) and the active region (6). The first and second current-injection layers (5, 8) are in contact with a first and a second metallic contact (11, 12), respectively. The first and/or second DBR (4, 10) are formed of alternating Aluminum oxide and Al(x)Ga(1−x)As containing layers. The proposed design of this VCSEL allows an increased efficiency and lower production costs of such a laser since the top and bottom DBRs may be formed of a considerable reduced thickness.

A method for manufacturing a semiconductor optical modulator includes forming a p-type semiconductor layer on a main surface of a p-type semiconductor substrate; forming a pair of stripe-shaped masks on the p-type semiconductor layer, the stripe-shaped masks extending in a first direction along the main surface of the p-type semiconductor substrate and being spaced apart from each other; simultaneously forming a hole and a pair of stripe structures extending in the first direction by etching the p-type semiconductor layer through the stripe-shaped masks, the pair of stripe structures defining the hole; after removing the stripe-shaped masks, forming a buried layer in the hole; forming a core layer on the buried layer and the stripe structures; and forming an upper cladding layer on the core layer. The buried layer is made of a semiconductor material with a lower optical absorption loss than that of the p-type semiconductor layer.