Abstract:
An electroluminescent device emits light at a pump wavelength. A first photoluminescent element covers first and second regions of the electroluminescent device and converts at least some of the pump light from the first region of the electroluminescent device to light at a first wavelength. A second photoluminescent element covers the second region of the electroluminescent device without covering the first region of the electroluminescent device and converts at least some of the light of the pump wavelength to light at a second wavelength different from the first wavelength. In some embodiments the first and second photoluminescent elements convert substantially all of the pump light incident from the first and second regions of the electroluminescent device respectively. An etch-stop layer may separate the first and second photoluminescent elements.
Abstract:
Light emitting devices and methods of fabricating the same are disclosed. The light emitting device includes a light emitting diode (LED) that emits blue or UV light and is attached to a semiconductor construction. The semiconductor construction includes a re-emitting semiconductor construction that includes at least one layer of a II-VI compound and converts at least a portion of the emitted blue or UV light to longer wavelength light. The semiconductor construction further includes an etch-stop construction that includes an AlInAs or a GaInAs compound. The etch-stop is capable of withstanding an etchant that is capable of etching InP.
Abstract:
Optical connectors are provided for connecting sets of optical waveguides, such as optical fiber ribbons to each other, to printed circuit boards, or to backplanes. The provided connectors utilize expanded beam optics with non-contact optical mating resulting in relaxed mechanical precision requirements. The provided connectors can have low optical loss, are easily scalable to high channel count (optical fibers per connector) and can be compatible with low insertion force blind mating.
Abstract:
Solar cells exhibiting improved conversion efficiency are disclosed. Particularly, multi-pn junction solar cells that contain a current spreading layer as well as concentrating photovoltaic modules that include such a solar cell and light concentrating optics are disclosed. The multi-pn junctions in question may generally be made up of III-V semiconductor materials, while the current spreading layer may generally be made up of II-VI semiconductor materials.
Abstract:
We describe stacked photovoltaic modules, and components thereof, in which at least one booster cell is combined with at least one primary cell in a stacked configuration. The booster cell may be in the form of a polycrystalline film disposed on a transparent substrate, such as a glass substrate, and the film may be patterned to form multiple booster cells. The booster cell includes an n-type layer and a p-type layer; the n-type layer may include polycrystalline zinc sulfide (ZnS), and the p-type layer may include polycrystalline zinc telluride (ZnTe). The n-type layer may have a band gap energy of at least 3.5 eV, and the p-type layer may have a band gap energy of at least 2 or at least 2.2 eV, or in a range from 2.2 to 2.3 eV. An intrinsic layer, also comprising polycrystalline ZnTe, may reside between the n-type and p-type layers.
Abstract:
Light emitting system (100), particularly, light emitting systems that utilize semiconductor wavelength converting regions (104), and methods of producing such systems are disclosed. The light emitting systems and methods of producing such systems seek to frustrate recombination of free carriers that are associated with wavelength converting regions.
Abstract:
A projection system and a display that incorporates the projection system are provided. The projection system includes at least one electroluminescent device that emits a first wavelength of light, at least one semiconductor multilayer stack that downconverts the first wavelength of light to a second wavelength of light, and a scanning optical element that transmits the light along a scanned direction. The electroluminescent device can be part of an array of electroluminescent devices, and can be monolithic. The semiconductor multilayer stack can be part of an array of semiconductor multilayer stacks, and can also be monolithic. The scanning optical element can be positioned to scan the electroluminescent device across the semiconductor multilayer stack, or it can be positioned to scan the downconverted light after it has left the semiconductor multilayer stack.
Abstract:
A lighting system provides a system optical output, such as white light, as a function of an applied electrical signal. The system output can be characterized by a color temperature or other measure that represents the color or output spectrum of the output. The system is designed so that the color temperature changes as a function of the applied electrical signal. The changes in color temperature are at least in part a result of a phenomenon known as "current crowding".
Abstract:
Methods of making flexible circuit films include providing a polymer film or other flexible substrate having a plurality of alignment marks and a photosensitive material thereon. The substrate passes around a suitable roller, belt, or other inelastic conveyor such that the substrate and the conveyor move together at least from a first location to a second location. Positions of a first set of the alignment marks on a first portion of the substrate are measured when such portion is at the first location, and the measured positions can be used to calculate a distortion of the substrate. The photosensitive material is then patternwise exposed when the first portion of the substrate has moved to the second location. The patternwise exposing is based on the measured positions of the first set of alignment marks, and may include exposing the web with a distortion-adjusted pattern. Related systems and articles are also disclosed.
Abstract:
Light emitting systems are disclosed. The light emitting system emits an output light that has a first color. The light emitting system includes a first electroluminescent device that emits light at a first wavelength in response to a first signal. The first wavelength is substantially independent of the first signal. The intensity of the emitted first wavelength light is substantially proportional to the first signal. The light emitting system further includes a first luminescent element that includes a second electroluminescent device and a first light converting layer. The second electroluminescent device emits light at a second wavelength in response to a second signal. The first light converting layer includes a semiconductor potential well and converts at least a portion of light at the second wavelength to light at a third wavelength that is longer than the second wavelength. The light emitting system combines light at the first wavelength with light at the third wavelength to form the output light at the first color. When one of the first and second signals changes from about 50% of a maximum rating of the signal to about 100% of the maximum rating, but the ratio of the first signal to the second signal remains substantially unchanged, the first color of the output light remains substantially unchanged.