Abstract:
A light emitting display for generating a selectable character (number, letter or alphanumeric character) comprises a plurality of independently operable light emitting display elements (segments). Each display element comprises: a light guiding medium having a light emitting display face; at least one excitation source (LED) associated with the light guiding medium and independently operable to generate excitation light of a first wavelength range and couple the excitation light into the light guiding medium; and a pattern of at least one phosphor material provided on the light emitting surface and configured to define the light emitting element wherein the phosphor material absorbs at least a part of the excitation light and emits light of a second wavelength range. Each display element can comprise a discrete light guiding medium or display elements can be defined within a single light guiding medium by one or more light reflecting planes.
Abstract:
A method of fabricating a light emitting device having a specific target color, CIE xy, of emitted light is described. The device comprises a light emitting diode that is operable to emit light of a first wavelength range and at least one phosphor material which converts at least a part of the light into light of a second wavelength range wherein light emitted by the device comprises the combined light of the first and second wavelength ranges. The method comprises: depositing a pre-selected quantity of the at least one phosphor material on a light emitting surface of the light emitting diode; operating the light emitting diode; measuring the color of light emitted by the device; comparing the measured color with the specific target color; and depositing and/or removing phosphor material to attain the desired target color.
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:
A color/color temperature tunable light emitting device comprises: an excitation source (LED) operable to generate light of a first wavelength range and a wavelength converting component comprising a phosphor material which is operable to convert at least a part of the light into light of a second wavelength range. Light emitted by the device comprises the combined light of the first and second wavelength ranges. The wavelength converting component has a wavelength converting property (phosphor material concentration per unit area) that varies spatially. The color of light generated by the source is tunable by relative movement of the wavelength converting component and excitation source such that the light of the first wavelength range is incident on a different part of the wavelength converting component and the generated light comprises different relative proportions of light of the first and second wavelength ranges.
Abstract:
A photo-luminescence liquid crystal display 100 comprises: a display panel 104 and a radiation source 102 (blue or UV LED) for generating excitation radiation for operating the display. The display panel 104 comprises transparent front 110 and back 112 plates; a liquid crystal (LC) 114 disposed there between; and a matrix of electrodes 120 (array of thin film transistors) defining red, green and blue pixel areas of the display and operable to selectively induce an electric field across the liquid crystal 114 in the pixel areas for controlling transmission of light through the pixels areas. Red 130 and green 132 phosphor materials are provided on the back plate corresponding to the red and green pixel areas and respectively emit red (R) and green (G) light in response to the excitation radiation. The LCD can further comprise a blue phosphor material 134 on the back plate corresponding to blue pixel areas.
Abstract:
The present invention relates to methods and apparatus for synthesizing combinatorial materials libraries using pyrolysis techniques. In certain embodiments, the methods involve varying the precursors and/or reactant gases in an operating pyrolysis unit to continuously vary the resulting nanoparticle composition and collecting different nanoparticles at different locations on a substrate using a spatially addressable particle collector.
Abstract:
Novel phosphor systems are disclosed having the formula A2SiO4:Eu2+D, where A is at least one of a divalent metal selected from the group consisting of Sr, Ca, Ba, Mg, Zn, and Cd; and D is a dopant selected from the group consisting of F, Cl, Br, I, P, S and N. In one embodiment, the novel phosphor has the formula (Sr1-x-yBaxMy)2 SiO4:Eu2+F (where M is one of Ca, Mg, Zn, or Cd in an amount ranging from 0
Abstract:
This invention provides novel cadmium tungstate scintillator materials that show improved radiation hardness. In particular, it was discovered that doping of cadmium tungstate (CdWO4) with trivalent metal ions or monovalent metal ions is particularly effective in improving radiation hardness of the scintillator material.
Abstract:
A light emitting sign comprising a light emitting display surface including at least one phosphor, and at least one radiation source configured to irradiate the display surface with excitation energy such that the phosphor emits light of a selected color. The sign further comprises a filter which is substantially transparent to light emitted by the display surface, filtering other colors of light. The display surface may be configured into a shape of a character, a symbol, or a device. Alternatively, a mask having at least one window substantially transparent to the emitted light and/or at least one light blocking region may be provided in which the window and/or light blocking region define a character, a symbol, or a device.
Abstract:
Methods and systems for spatially resolved spin resonance detection in a sample of material are disclosed. Also disclosed are methods and systems for spatially resolved impedance measurements in a sample of material. The disclosed methods and samples can be used in screening of plurality of biological, chemical and material samples.