| Patent application number | Description | Published |
|---|
| 20080265263 | Polarized Semiconductor Light Emitting Device - A light emitting device includes a light emitting diode (LED), a concentrator element, such as a compound parabolic concentrator, and a wavelength converting material, such as a phosphor. The concentrator element receives light from the LED and emits the light from an exit surface, which is smaller than the entrance surface. The wavelength converting material is, e.g., disposed over the exit surface. The radiance of the light emitting diode is preserved or increased despite the isotropic re-emitted light by the wavelength converting material. In one embodiment, the polarized light from a polarized LED is provided to a polarized optical system, such as a microdisplay. In another embodiment, the orthogonally polarized light from two polarized LEDs is combined, e.g., via a polarizing beamsplitter, and is provided to non-polarized optical system, such as a microdisplay. If desired, a concentrator element may be disposed between the beamsplitter and the microdisplay. | 10-30-2008 |
| 20090173960 | SEMICONDUCTOR LIGHT EMITTING DEVICE WITH PRE-FABRICATED WAVELENGTH CONVERTING ELEMENT - A semiconductor light emitting device is provided with a separately fabricated wavelength converting element. The wavelength converting element, of e.g., phosphor and glass, is produced in a sheet that is separated into individual wavelength converting elements, which are bonded to light emitting devices. The wavelength converting elements may be grouped and stored according to their wavelength converting properties. The wavelength converting elements may be selectively matched with a semiconductor light emitting device, to produce a desired mixture of primary and secondary light. | 07-09-2009 |
| 20090261361 | III-NITRIDE LIGHT EMITTING DEVICE WITH DOUBLE HETEROSTRUCTURE LIGHT EMMITTING REGION - A III-nitride light emitting layer is disposed between an n-type region and a p-type region in a double heterostructure. At least a portion of the III-nitride light emitting layer has a graded composition. | 10-22-2009 |
| 20100148151 | LIGHT EMITTING DEVICES WITH IMPROVED LIGHT EXTRACTION EFFICIENCY - A device includes a light emitting structure and a wavelength conversion member comprising a semiconductor. The light emitting structure is bonded to the wavelength conversion member. In some embodiments, the light emitting structure is bonded to the wavelength conversion member with an inorganic bonding material. In some embodiments, the light emitting structure is bonded to the wavelength conversion member with a bonding material having an index of refraction greater than 1.5. | 06-17-2010 |
| 20100200886 | WAVELENGTH-CONVERTED SEMICONDUCTOR LIGHT EMITTING DEVICE - Embodiments of the invention include a light emitting structure comprising a light emitting layer. A first luminescent material comprising a phosphor is disposed in a path of light emitted by the light emitting layer. A second luminescent material comprising a semiconductor is also disposed in a path of light emitted by the light emitting layer. The second luminescent material is configured to absorb light emitted by the light emitting layer and emit light of a different wavelength. In some embodiments, one of the first and second luminescent materials may be bonded to the semiconductor structure. | 08-12-2010 |
| 20100289044 | WAVELENGTH CONVERSION FOR PRODUCING WHITE LIGHT FROM HIGH POWER BLUE LED - A white light LED is described that uses an LED die that emits visible blue light in a wavelength range of about 450-470 nm. A red phosphor or quantum dot material converts some of the blue light to a visible red light having a peak wavelength between about 605-625 nm with a full-width-half-maximum (FWHM) less than 80 nm. A green phosphor or quantum dot material converts some of the blue light to a green light having a FWHM greater than 40 nm, wherein the combination of the blue light, red light, and green light produces a white light providing a color rendering of R | 11-18-2010 |
| 20110084293 | MULTI-GRAIN LUMINESCENT CERAMICS FOR LIGHT EMITTING DEVICES - A ceramic body is disposed in a path of light emitted by a light source. The light source may include a semiconductor structure comprising a light emitting region disposed between an n-type region and a p-type region. The ceramic body includes a plurality of first grains configured to absorb light emitted by the light source and emit light of a different wavelength, and a plurality of second grains. For example, the first grains may be grains of luminescent material and the second grains may be grains of a luminescent material host matrix without activating dopant. | 04-14-2011 |
| 20110156056 | WAVELENGTH-CONVERTED SEMICONDUCTOR LIGHT EMITTING DEVICE - A material such as a phosphor is optically coupled to a semiconductor structure including a light emitting region disposed between an n-type region and a p-type region, in order to efficiently extract light from the light emitting region into the phosphor. The phosphor may be phosphor grains in direct contact with a surface of the semiconductor structure, or a ceramic phosphor bonded to the semiconductor structure, or to a thin nucleation structure on which the semiconductor structure may be grown. The phosphor is preferably highly absorbent and highly efficient. When the semiconductor structure emits light into such a highly efficient, highly absorbent phosphor, the phosphor may efficiently extract light from the structure, reducing the optical losses present in prior art devices. | 06-30-2011 |
