2838 results about "High index" patented technology

UV reflectors incorporated in UV LED-based light sources reduce the amount of UV radiation emission into the surroundings and increase the efficiency of such light sources. UV reflectors are made of nanometer-sized particles having a mean particle diameter less than about one-tenth of the wavelength of the UV light emitted by the UV LED, dispersed in a molding or casting material surrounding the LED. Other UV reflectors are series of layers of materials having alternating high and low refractive indices; each layer has a physical thickness of one quarter of the wavelength divided by the refractive index of the material. Nanometer-sized textures formed on a surface of the multilayered reflector further reduce the emission of UV radiation into the surroundings. UV LED-based light sources include such a multilayered reflector disposed on an encapsulating structure of a transparent material around a UV LED, particles of a UV-excitable phosphor dispersed in the transparent material. Alternatively, the transparent material also includes nanometer-sized particles of a UV-radiation scattering material.

Blends of oligomeric urethane multi(meth)acrylate; optionally at least one other monomer selected from the group consisting of acrylic monomers, styrenic monomers and ethylenically unsaturated nitrogen heterocycles, preferably a polyol multi(meth)acrylate; and nanoparticles of an ethylenically unsaturated, preferably (meth)acrylic-functionalized, titanium or zirconium compound can be cured by ultraviolet radiation in contact with a photoinitiator to produce optical resinous articles having high refractive indices, haze ratings of at most 5% and other properties which may be tailored according to the desired use.

Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent lens having a refractive index for light emitted by the active region preferably greater than about 1.5, more preferably greater than about 1.8. A method of bonding a transparent lens to a light emitting device having a stack of layers including semiconductor layers comprising an active region includes elevating a temperature of the lens and the stack and applying a pressure to press the lens and the stack together. Bonding a high refractive index lens to a light emitting device improves the light extraction efficiency of the light emitting device by reducing loss due to total internal reflection. Advantageously, this improvement can be achieved without the use of an encapsulant.

The present invention is intended to provide an image pickup device-equipped rear view mirror with improved image pickup performance, glare prevention and appearance (design) in addition to improved performance as a vehicle mirror. A mirror element is formed by forming a reflecting film consisting of high refractive index material films and a low refractive index material film on a back surface of a transparent glass substrate. The integrating sphere reflectance of the mirror element in the visible range is 40% to 60% and the near-infrared transmittance is no less than 70% for the whole or part of the band belonging to the near-infrared range within the entire sensitive wavelength range of the near-infrared camera. A black mask member is attached to an entire back surface of the reflecting film. The near-infrared camera is arranged behind the black mask member. The region corresponding to the area for the image-pickup by the near-infrared camera within the entire region of the black mask member is formed of a visible-light absorption and near-infrared transmission filter. The near-infrared transmittance of the visible-light absorption and near-infrared transmission filter is no less than 70% for the whole or part of the band belonging to the near-infrared range within the entire sensitive wavelength range of the near-infrared camera.

Light efficient packaging configurations for LED lamps using high refractive index encapsulants. The packaging configurations including dome (bullet) shaped LED's, SMD (surface mount device) LED's and a hybrid LED type, including a dome mounted within a SMD package. In another embodiment used with SMD LED devices a relatively small semi-hemispherical “blob” of HRI encapsulant surrounds the LED chip with the remainder of the SMD cavity filled with conventional encapsulant. The packaging configurations increase the LED's light emission efficiency at a reasonable cost and in a commercially viable manner, by maximizing the light efficiency while minimizing the amount of high refractive index encapsulant used.

A structural shape on the surface of an optical substrate is such that the brightness of diffuse light departing from the surface of the optical substrate at certain off axis angles is reduced, at the expense of a small reduction in peak brightness measured near the viewing axis. The net result is an overall increase in useful illumination. A cross section of a prism as the structural shape has a curved sidewall or facet. A material with a relatively high index of refraction combined with a prismatic structure having a modified prism geometry improves brightness.

A projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines has a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective. At least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength.

A solar concentrator is provided that comprises two stages. The first stage comprises either a trough-shaped concentrator cusp unit having two major opposed sides joined by two ends. The inner surfaces of the first stage concentrator are mirrored. Further, the ends have two flat, angled surfaces, while the two sides have a Bezier-generated cylindrical shape that approximate parabolic surfaces followed by a straight section. The second stage comprises a bi-axial gradient refractive index (GRIN) element, in which two gradient refractive index materials, each having a high index surface and a low index surface, are joined together along their high index surfaces. The two ends of the bi-axial element are flat, while the two sides also have a Bezier-generated cylindrical shape that approximate parabolic surfaces followed by a straight section. The top surface of the bi-axial element is provided with a cylindrical surface, while the bottom, or exit, surface is ground flat. The high index boundary is parallel to the side surfaces of the first stage unit. A solar cell is bonded to the flat exit surface of the second stage of the concentrator of the present invention. An array of such concentrators and solar cells, in which the solar cells are electrically interconnected, may then be deployed for converting solar energy into useful electrical energy. The 2-D/3-D concentrator evidences much lower mass than prior art concentrators. Further, as the array, or panel, of solar cells wobbles in space, the concentrator will continue to operate, even at lower efficiencies, due to the larger acceptance angle. Concentration ratios on the order of 50x are realized with the present concentrator. However, design studies allow concentration ratios in excess of 300x when used with 3-D versions of the same concept. The second stage can comprise mirrored surfaces. Or, the first stage can comprise a conical section and the second stage a radial GRIN element.

The invention provides an organic/inorganic hybrid material with a high refractive index at telecommunications wavelengths. Energy curable compositions of the present invention include condensed metal oxide nanoparticles, a high refractive index organometallic coupling agent, an energy curable organometallic coupling agent, and a high refractive index monomer or oligomer. Polymeric materials of the present invention include condensed metal oxide nanoparticles having a mixture of organometallic coupling agents covalently bound to the exterior surface of the nanoparticles and a high refractive index solid polymer matrix, wherein the mixture of organometallic coupling agents includes a high refractive index coupling agent, and a coupling agent covalently bound to the polymer matrix. The materials of the present invention are useful in making optical devices for telecommunications applications.

In certain embodiments of this invention, an improved multilayer anti-reflection (AR) coating is provided on the exterior surface of the front glass substrate of a photovoltaic device. This AR coating functions to reduce reflection of desirable wavelengths from the front glass substrate, thereby allowing more light within the desirable solar spectrum to pass through the incident glass substrate and reach the photovoltaic semiconductor film so that the photovoltaic device can operate more efficiently. Also, the AR coating can reduce the amount of undesirable light (e.g., at least some IR and/or UV radiation) which reaches the semiconductor film of the device. In certain example embodiments, the multilayer AR coating includes a plurality of pairs of alternating high refractive index and low refractive index layers.

Certain example embodiments of this invention relate to an electrode (e.g., front electrode) for use in a photovoltaic device or the like. In certain example embodiments, a transparent conductive oxide (TCO) of the front electrode for use in a photovoltaic device is of or includes titanium oxide doped with one or more of Nb, Zn and/or Al. Additional layers may also be provided in the front electrode in certain example embodiments. It has been found that the use of transparent conductive TiO_x(:Nb) or TiZnO_x(:Al and/or Nb), in a front electrode of a photovoltaic device, is advantageous in that such materials have a high refractive index (n) and have a higher transparency than conventional titanium suboxide (TiO_x). Thus, the use of such materials in the context of a front electrode of a photovoltaic device reduces light reflection due to the high refractive index, and increases transmission into the active semiconductor film due to the higher transmission characteristics thereof, thereby improving the efficiency of the device.

Light emitting devices with improved light extraction efficiency are provided. The light emitting devices have a stack of layers including semiconductor layers comprising an active region. The stack is bonded to a transparent optical element having a refractive index for light emitted by the active region preferably greater than about 1.5, more preferably greater than about 1.8. A method of bonding a transparent optical element (e.g., a lens or an optical concentrator) to a light emitting device comprising an active region includes elevating a temperature of the optical element and the stack and applying a pressure to press the optical element and the light emitting device together. A block of optical element material may be bonded to the light emitting device and then shaped into an optical element. Bonding a high refractive index optical element to a light emitting device improves the light extraction efficiency of the light emitting device by reducing loss due to total internal reflection. Advantageously, this improvement can be achieved without the use of an encapsulant.

A color filterless display device performing color display for expressing one pixel by three RGB sub-pixels includes: a light source; a diffraction grating for separating a light irradiated from this light source into lights of a plurality of wavelength regions; a cylindrical lens array for receiving the separated light and condensing the light while corresponding to each of the sub-pixels; and a liquid crystal cell including a structure portion for correcting an angle of the condensed light for all sub-pixels, wherein, in the structure portion of this liquid crystal cell, a side onto which a light from the cylindrical lens array is made incident is made of a high refractive index layer, an emitting side from which the light is emitted is made of a low refractive index layer, and a Fresnel-type microprism structure is formed by the high refractive index layer and the low refractive index layer.

An organic EL device (1) comprises: a light-transmissive substrate (2); a transparent electrode (4); an organic emitting layer (5); and an opposing electrode (6). A light-extraction layer (3) provided by layering a high refractive index layer (31) adjoining the transparent electrode (4) and a low refractive index layer (32) adjoining the light-transmissive substrate (2) includes recess-protrusion units (31A) each provided by a protrusion (311) and a recess (312) at an interface between the high refractive index layer (31) and the low refractive index layer (32). In at least one of the recess-protrusion units (31A), a distance d₁ from the interface between the high refractive index layer (31) and the low refractive index layer (32) to an interface between the transparent electrode (4) and the high refractive index layer (31) is equal to or more than an optical coherence length and a height d₂ of the protrusion (311), a width d₃ of the protrusion (311) and a gap d4 between the protrusion (311) and another protrusion (311) adjoining the protrusion across the recess (312) is 1 μm or more.

There is disclosed an anti-reflection film comprising 5-65% by volume of inorganic fine particles having an average particle size of 1-200 nm and having a core/shell structure, and 35-95% by volume of a polymer, wherein a high-refractive-index layer having a refractive index of 1.65-2.40 and a low-refractive-index layer having a refractive index of 1.30-1.55 are laminated. There is also disclosed a polarizing plate and image display device utilizing the anti-reflection film. The anti-reflection film is suitable for mass production.

Light guide devices comprising an intermediate layer of low refractive index between higher refractive index elements are described. The light guide devices are suitable for use in backlights.

A light emitting diode (LED) includes a p-type layer of material, an n-type layer of material and an active layer between the p-type layer and the n-type layer. A roughened layer of transparent material is adjacent one of the p-type layer of material and the n-type layer of material. The roughened layer of transparent material has a refractive index close to or substantially the same as the refractive index of the material adjacent the layer of transparent material, and may be a transparent oxide material or a transparent conducting material. An additional layer of conductive material may be between the roughened layer and the n-type or p-type layer.

Systems and methods for modulating light with light in high index contrast waveguides clad with graphene. Graphene exhibits a large nonlinear electro-optic constant χ³. Waveguides fabricated on SOI wafers and clad with graphene are described. Systems and methods for modulating light with light are discussed. Optical logic gates are described. Waveguides having closed loop structures such as rings and ovals, Mach-Zehnder interferometer, grating, and Fabry-Perot configurations, are described. Optical signal processing methods, including optical modulation at Terahertz frequencies, are disclosed. Optical detectors are described. Microelectromechanical and nanoelectromechanical systems using graphene on silicon substrates are described.

An (Al, Ga, In)N and ZnO direct wafer bonded light emitting diode (LED) combined with a shaped optical element in which the directional light from the ZnO cone or any high refractive index material in contact with the LED surface entering the shaped optical element is extracted to air.