Abstract:
A photoluminescence color display comprises a display panel that displays red, green and blue pixel areas, an excitation source operable to generate excitation radiation for operating the display, and a photoluminescence color-element plate. The color-element plate comprises at least one photoluminescence material, such as a phosphor material or quantum dots, that is operable to emit light corresponding to red, green and blue pixel areas of the display in response to said excitation radiation. Additionally, the photo-luminescence color display comprises a wavelength selective filter that is provided between the color-element plate and the excitation source. The filter has a transmission characteristic that allows the passage of excitation radiation from the excitation source to excite the at least one photoluminescence material whilst preventing the passage of photoluminescence light back to the excitation source thereby prevent cross contamination of light among the different pixel areas of the display.
Abstract:
Embodiments of the present invention are directed to nitride-based, red-emitting phosphors in red, green, and blue (RGB) lighting systems, which in turn may be used in backlighting displays and warm white-light applications. In particular embodiments, the red-emitting phosphor is based on CaAlSiN3 type compounds activated with divalent europium. In one embodiment, the nitride-based, red emitting compound contains a solid solution of calcium and strontium compounds (Ca,Sr)AlSiN3:Eu2+, wherein the impurity oxygen content is less than about 2 percent by weight. In another embodiment, the (Ca,Sr)AlSiN3:Eu2+ compounds further contains a halogen in an amount ranging from about zero to about 2 atomic percent, where the halogen may be fluorine (F), chlorine (Cl), or any combination thereof. In one embodiment at least half of the halogen is distributed on 2-fold coordinated nitrogen (N2) sites relative to 3-fold coordinated nitrogen (N3) sites.
Abstract:
A method of manufacturing an LED lighting arrangement, comprises: receiving an optical component having a diffusing material that is light diffusive and at least one photoluminescent material that is excitable by light of a first wavelength range and which emits light of a second wavelength range; receiving an LED assembly that is operable to generate the light of the first wavelength range and mounting the optical component to the LED assembly to form the LED lighting arrangement. The optical component having the diffusing and photoluminescent materials is mass produced separately from the LED assembly and can be selected such that light generated by the optical component combined with the light generated by the LED assembly corresponds to light of a selected color. Also disclosed are LED lighting arrangements, components for LED lighting arrangements and methods of fabricating an optical component.
Abstract:
An optical component for an LED lighting arrangement comprises a transparent material having a surface and one or more photoluminescent (phosphor) materials deposited as a layer on the surface of the transparent material. The phosphor material layer can be deposited using a deposition approach including spraying, dropping, printing, painting, spin coating or tape casting. The phosphor material layer has a thickness in a range of 20 to 500 μm. The component can further comprising a light diffusing material which can be provided in a separate layer from the phosphor material layer or provided in the phosphor material layer. The light diffusing material can be deposited using a deposition approach including spraying, dropping, printing, painting, spin coating or tape casting.
Abstract:
A photoluminescent composition (“phosphor ink”) comprises a suspension of particles of at least one blue light (380 nm to 480 nm) excitable phosphor material in a light transmissive liquid binder in which the weight loading of at least one phosphor material to binder material is in a range 40% to 75%. The binder can be U.V. curable, thermally curable, solvent based or a combination thereof and comprise a polymer resin; a monomer resin, an acrylic, a silicone or a fluorinated polymer. The composition can further comprise particles of a light reflective material suspended in the liquid binder. Photoluminescence wavelength conversion components; solid-state light emitting devices; light emitting signage surfaces and light emitting signage utilizing the composition are disclosed.
Abstract:
The present invention provides a cost effective process of generating LixMyZO4/carbon composite material. Further, this novel method of preparation can be modified by adding a dopant and the calcinations can be carried out using microwave heating to reduce the synthesis time and cost. The LixMyZO4/carbon composite material can be used as a cathode for a secondary electrochemical cell. Selection of one or more metals in the cathode material can be used change the voltage, the capacity, and the energy density of the electrochemical cell.
Abstract:
A lighting system comprises at least one excitation source (5), preferably an LED, operable to generate and radiate excitation radiation of a first wavelength (λ1); a shade (4) configured to at least in part surround the at least one source (5) and remotely located thereto; and at least one phosphor (16) provided in or on at least a part of the shade (4), wherein the phosphor (16) emits radiation of a different wavelength in response to incident excitation radiation. The phosphor can be provided on a part of an outer or inner surface of the shade. Alternatively, or in addition, the phosphor is incorporated within the shade. The lighting system finds particular application as a hanging, a desk, a floor standing, a wall mountable, a spot, an outdoor or an accent lighting fixture.
Abstract:
A solid-state lamp comprises a body having a first chamber with inlet apertures and a second chamber with outlet apertures. The chambers are interconnected in fluid communication by one or more passages. The lamp further comprises a thermally conductive substrate having a heat radiating surface located within at least one chamber and one or more solid-state light emitters, typically LEDs, mounted in thermal communication with the thermally conductive substrate. The lamp is configured such that in operation heat generated by the LEDs is radiated by the substrate into one or both chambers causing a difference in air pressure between the chambers that results in surrounding air being drawn into the inlet apertures, flowing through the chambers via the interconnecting passages in the substrate and exiting through the outlet apertures thereby cooling the substrate and LEDs.
Abstract:
A light emitting device comprises an excitation source (20), one or more light emitting diode(s) operable to generate excitation light of a first wavelength range (λ1) and a light emitting surface (14) having a phosphor material (26) which absorbs at least a part of the excitation light and emits light of a second wavelength range (λ2), wherein light (32) emitted by the device comprises combined light of the first and second wavelength ranges emitted by the light emitting surface. The device is characterized by the light emitting surface having one or more window areas (28) which does not include a phosphor material and which are substantially transparent to light of the first and second wavelengths. The light emitting surface can comprise a transparent substrate (14) having a pattern of phosphor material on a surface thereof with the one or more window areas evenly distributed over the light emitting surface.
Abstract:
An electrode material for a rechargeable electrochemical cell comprises a metal phosphate of general composition M1M2PO4 having an olivine structure in which alkali metal cations (MI=Li+, Na+, K+) occupy M1 sites and transition metal cations (MV=Fe, Mn, Co) having both divalent and trivalent oxidation states occupy M2 sites. The material further comprises trivalent and/or tetravalent metal cations (MIII=Al3+, Ga3+, In3+, Tl3+, Y3+, La3+, V3+, Cr3+, Mn3+, Fe3+, Co3+, Ti4+, MIV=Zr4+, Mo4, W4+) doped into an M2 site and additional alkali metal cations doped into an M2 site to thereby attain an overall charge balance of the material.