Patents by Inventor Nelson Tansu
Nelson Tansu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20230201389Abstract: A system for ultraviolet irradiation of objects and a method of using this system is disclosed. The system includes: an illuminating device positioned in a center section of an octagon shaped a base area and including one or more elongated light sources, each emitting ultraviolet light given by shortwave ultraviolet light (UV-C light) and extending in parallel to a normal on the base area; a set of rotatable mesh grids arranged around the base area such that the mesh grids surround the illuminating device and configured to be equipped with the objects; and a set of reflectors including a set of movable side reflectors, wherein the reflectors are configured to be arranged such, that they form a resonator surrounding the mesh grids surrounding the illuminating device.Type: ApplicationFiled: April 14, 2021Publication date: June 29, 2023Inventors: Nelson Tansu, Axel Y. Tansu, Adela Gozali Yose, Renbo Song, Anthony Jeffers, Grant Reed, Ankhitha Manjunatha, Theodore L. Bowen, Christopher Roscher, Jay W. Johnson, Eric Tesoriero
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Publication number: 20200035790Abstract: A material structure and system for generating a III-Nitride digital alloy.Type: ApplicationFiled: July 8, 2019Publication date: January 30, 2020Inventors: Nelson TANSU, Wei SUN, Chee-Keong TAN
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Publication number: 20190236120Abstract: At present, a vast number of technologies are designed specifically for users that are able to employ the use of sight. Additionally, many products designed to allow the visually impaired to use these technologies are expensive, and often not easy to use. In order to expand the benefits of technology to the visually impaired, we have invented an Electronic Braille Interface that can connect to any device with a USB port (laptops, cell phones, e-readers, etc.) and effectively translate ASCII characters from the device into physical Braille characters. The Braille text will be displayed on the Electronic Braille Interface though moveable pins that, in groups of six, are able to display different Braille characters in the same fashion as normal, stationary Braille text. The user will be able to feel the pins and interpret the Braille characters.Type: ApplicationFiled: January 30, 2018Publication date: August 1, 2019Inventors: Eric Thomas Reid, Katherine Isabella Porfirio, Nelson Tansu
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Patent number: 10347722Abstract: A material structure and system for generating a III-Nitride digital alloy.Type: GrantFiled: March 4, 2016Date of Patent: July 9, 2019Assignee: LEHIGH UNIVERSITYInventors: Nelson Tansu, Wei Sun, Chee-Keong Tan
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Patent number: 10115859Abstract: A symmetrical quantum well active layer provides enhanced internal quantum efficiency. The quantum well active layer includes an inner (central) layer and a pair of outer layers sandwiching the inner layer. The inner and outer layers have different thicknesses and bandgap characteristics. The outer layers are relatively thick and include a relatively low bandgap material, such as InGaN. The inner layer has a relatively lower bandgap material and is sufficiently thin to act as a quantum well delta layer, e.g., comprising approximately 6 ? or less of InN. Such a quantum well structure advantageously extends the emission wavelength into the yellow/red spectral regime, and enhances spontaneous emission. The multi-layer quantum well active layer is sandwiched by barrier layers of high bandgap materials, such as GaN.Type: GrantFiled: December 15, 2010Date of Patent: October 30, 2018Assignee: Lehigh UniversityInventors: Nelson Tansu, Hongping Zhao, Guangyu Liu, Gensheng Huang
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Thermoelectric materials based on single crystal AlInN—GaN grown by metalorganic vapor phase epitaxy
Patent number: 9525117Abstract: The invention is a thermoelectric device fabricated by growing a single crystal AlInN semiconductor material on a substrate, and a method of fabricating same. In a preferred embodiment, the semiconductor material is AlInN grown on and lattice-matched to a GaN template on a sapphire substrate, and the growth is performed using metalorganic vapor phase epitaxy (MOVPE).Type: GrantFiled: December 8, 2010Date of Patent: December 20, 2016Assignee: LEHIGH UNIVERSITYInventors: Nelson Tansu, Hua Tong, Jing Zhang, Guangyu Liu, Gensheng Huang -
Publication number: 20160260804Abstract: A material structure and system for generating a III-Nitride digital alloy.Type: ApplicationFiled: March 4, 2016Publication date: September 8, 2016Inventors: Nelson TANSU, Wei SUN, Chee-Keong TAN
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Patent number: 9349910Abstract: A light emitting device comprising a staggered composition quantum well (QW) has a step-function-like profile in the QW, which provides higher radiative efficiency and optical gain by providing improved electron-hole wavefunction overlap. The staggered QW includes adjacent layers having distinctly different compositions. The staggered QW has adjacent layers Xn, wherein X is a quantum well component and in one quantum well layer n is a material composition selected for emission at a first target light regime, and in at least one other quantum well layer n is a distinctly different composition for emission at a different target light regime. X may be an In-content layer and the multiple Xn-containing layers provide a step function In-content profile.Type: GrantFiled: January 30, 2014Date of Patent: May 24, 2016Assignee: Lehigh UniversityInventors: Nelson Tansu, Ronald A. Arif, Yik Khoon Ee, Hongping Zhao
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Patent number: 8907321Abstract: A III-nitride based device provides improved current injection efficiency by reducing thermionic carrier escape at high current density. The device includes a quantum well active layer and a pair of multi-layer barrier layers arranged symmetrically about the active layer. Each multi-layer barrier layer includes an inner layer abutting the active layer; and an outer layer abutting the inner layer. The inner barrier layer has a bandgap greater than that of the outer barrier layer. Both the inner and the outer barrier layer have bandgaps greater than that of the active layer. InGaN may be employed in the active layer, AlInN, AlInGaN or AlGaN may be employed in the inner barrier layer, and GaN may be employed in the outer barrier layer. Preferably, the inner layer is thin relative to the other layers. In one embodiment the inner barrier and active layers are 15 ? and 24 ? thick, respectively.Type: GrantFiled: December 14, 2010Date of Patent: December 9, 2014Assignee: Lehigh UniveristyInventors: Nelson Tansu, Hongping Zhao, Guangyu Liu, Ronald Arif
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Publication number: 20140191189Abstract: A light emitting device comprising a staggered composition quantum well (QW) has a step-function-like profile in the QW, which provides higher radiative efficiency and optical gain by providing improved electron-hole wavefunction overlap. The staggered QW includes adjacent layers having distinctly different compositions. The staggered QW has adjacent layers Xn, wherein X is a quantum well component and in one quantum well layer n is a material composition selected for emission at a first target light regime, and in at least one other quantum well layer n is a distinctly different composition for emission at a different target light regime. X may be an In-content layer and the multiple Xn-containing layers provide a step function In-content profile.Type: ApplicationFiled: January 30, 2014Publication date: July 10, 2014Applicant: LEHIGH UNIVERSITYInventors: Nelson TANSU, Ronald A. ARIF, Yik Khoon EE, Hongping ZHAO
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Patent number: 8685767Abstract: A double-metallic deposition process is used whereby adjacent layers of different metals are deposited on a substrate. The surface plasmon frequency of a base layer of a first metal is tuned by the surface plasmon frequency of a second layer of a second metal formed thereon. The amount of tuning is dependent upon the thickness of the metallic layers, and thus tuning can be achieved by varying the thicknesses of one or both of the metallic layers. In a preferred embodiment directed to enhanced LED technology in the green spectrum regime, a double-metallic Au/Ag layer comprising a base layer of gold (Au) followed by a second layer of silver (Ag) formed thereon is deposited on top of InGaN/GaN quantum wells (QWs) on a sapphire/GaN substrate.Type: GrantFiled: December 8, 2010Date of Patent: April 1, 2014Assignee: Lehigh UniversityInventors: Nelson Tansu, Hongping Zhao, Jing Zhang, Guangyu Liu
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Patent number: 8659005Abstract: A light emitting device comprising a staggered composition quantum well (QW) has a step-function-like profile in the QW, which provides higher radiative efficiency and optical gain by providing improved electron-hole wavefunction overlap. The staggered QW includes adjacent layers having distinctly different compositions. The staggered QW has adjacent layers Xn wherein X is a quantum well component and in one quantum well layer n is a material composition selected for emission at a first target light regime, and in at least one other quantum well layer n is a distinctly different composition for emission at a different target light regime. X may be an In-content layer and the multiple Xn-containing a step function In-content profile.Type: GrantFiled: December 24, 2007Date of Patent: February 25, 2014Assignee: Lehigh UniversityInventors: Nelson Tansu, Ronald A. Arif, Yik Khoon Ee, Hongping Zhao
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Patent number: 8586963Abstract: A conventional semiconductor LED is modified to include a microlens layer over its light-emitting surface. The LED may have an active layer including at least one quantum well layer of InGaN and GaN. The microlens layer includes a plurality of concave microstructures that cause light rays emanating from the LED to diffuse outwardly, leading to an increase in the light extraction efficiency of the LED. The concave microstructures may be arranged in a substantially uniform array, such as a close-packed hexagonal array. The microlens layer is preferably constructed of curable material, such as polydimethylsiloxane (PDMS), and is formed by soft-lithography imprinting by contacting fluid material of the microlens layer with a template bearing a monolayer of homogeneous microsphere crystals, to cause concave impressions, and then curing the material to fix the concave microstructures in the microlens layer and provide relatively uniform surface roughness.Type: GrantFiled: December 8, 2010Date of Patent: November 19, 2013Assignee: Lehigh UniversityInventors: Nelson Tansu, James F. Gilchrist, Yik-Khoon Ee, Pisist Kumnorkaew
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Patent number: 8569737Abstract: A III-Nitride semiconductor LED provides broadband light emission, across all or most of the visible light wavelength spectrum, and a method for producing same. The LED includes a polarization field management template that has a three-dimensional patterned surface. The surface may be patterned with an array of hemispherical cavities, which may be formed by growing the template around a temporary template layer of spherical or other crystals. The method involves growing a quantum well layer on the patterned surface. The topographical variations in the patterned surface of the template cause corresponding topographical variations in the quantum well layer. These variations in spatial orientation of portions of the quantum well layer cause the polarization field of the quantum well layer to vary across the surface of the LED, which leads to energy transition shifting that provides “white” light emission across a broad wavelength spectrum.Type: GrantFiled: December 8, 2011Date of Patent: October 29, 2013Assignee: Lehigh UniversityInventors: Nelson Tansu, Xiaohang Li, Hongping Zhao, Guangyu Liu, James Foster Gilchrist, Pisist Kumnorkaew
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Patent number: 8541252Abstract: The use of an abbreviated GaN growth mode on nano-patterned AGOG sapphire substrates, which utilizes a process of using 15 nm low temperature GaN buffer and bypassing etch-back and recovery processes during epitaxy, enables the growth of high-quality GaN template on nano-patterned AGOG sapphire. The GaN template grown on nano-patterned AGOG sapphire by employing abbreviated growth mode has two orders of magnitude lower threading dislocation density than that of conventional GaN template grown on planar sapphire. The use of abbreviated growth mode also leads to significant reduction in cost of the epitaxy. The growths and characteristics of InGaN quantum wells (QWs) light emitting diodes (LEDs) on both templates were compared. The InGaN QWs LEDs grown on the nano-patterned AGOG sapphire demonstrated at least a 24% enhancement of output power enhancement over that of LEDs grown on conventional GaN templates.Type: GrantFiled: December 17, 2010Date of Patent: September 24, 2013Assignee: Lehigh UniversityInventors: Nelson Tansu, Helen M. Chan, Richard P. Vinci, Yik-Khoon Ee, Jeffrey Biser
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Publication number: 20120217472Abstract: A III-Nitride semiconductor LED provides broadband light emission, across all or most of the visible light wavelength spectrum, and a method for producing same. The LED includes a polarization field management template that has a three-dimensional patterned surface. The surface may be patterned with an array of hemispherical cavities, which may be formed by growing the template around a temporary template layer of spherical or other crystals. The method involves growing a quantum well layer on the patterned surface. The topographical variations in the patterned surface of the template cause corresponding topographical variations in the quantum well layer. These variations in spatial orientation of portions of the quantum well layer cause the polarization field of the quantum well layer to vary across the surface of the LED, which leads to energy transition shifting that provides “white” light emission across a broad wavelength spectrum.Type: ApplicationFiled: December 8, 2011Publication date: August 30, 2012Applicant: Lehigh UniversityInventors: Nelson Tansu, Xiaohang Li, Hongping Zhao, Guangyu Liu, James Foster Gilchrist, Pisist Kumnorkaew
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Patent number: 8076667Abstract: A tight emitting device comprises at least one p-type layer and at least one n-type layer and a microlens array surface. A method for improving light efficiency of a light emitting device, comprises depositing polystyrene microspheres by rapid convection deposition on surface of light emitting device; depositing a monolayer of close-packed SIO2 microspheres onto the polystyrene microspheres; and heal treating to convert the polystyrene microspheres into a planar microlayer film to provide a surface comprising substantially two-dimensional (2D) hexagonal close-packed SIO2 colloidal microsphere crystals partially imposed into a polystyrene monolayer film.Type: GrantFiled: December 24, 2007Date of Patent: December 13, 2011Assignee: Lehigh UniversityInventors: Nelson Tansu, Yik Khoon Ee, James F. Gilchrist, Pisit Kumnorkaew, Ronald A. Arif
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THERMOELECTRIC MATERIALS BASED ON SINGLE CRYSTAL AlInN-GaN GROWN BY METALORGANIC VAPOR PHASE EPITAXY
Publication number: 20110240082Abstract: The invention is a thermoelectric device fabricated by growing a single crystal AlInN semiconductor material on a substrate, and a method of fabricating same. In a preferred embodiment, the semiconductor material is AlInN grown on and lattice-matched to a GaN template on a sapphire substrate, and the growth is performed using metalorganic vapor phase epitaxy (MOVPE).Type: ApplicationFiled: December 8, 2010Publication date: October 6, 2011Applicant: Lehigh UniversityInventors: Nelson Tansu, Hua Tong, Jing Zhang, Guangyu Liu, Gensheng Huang -
Patent number: 8030641Abstract: A gallium nitride-based device has ? first GaN layer and ? type II quantum well active region over the GaN layer. The type II quantum well active region comprises at least one InGaN layer and at least one GaNAs layer, wherein the InGaN comprises ? graded molar In concentration.Type: GrantFiled: December 19, 2007Date of Patent: October 4, 2011Assignee: Lehigh UniversityInventors: Nelson Tansu, Ronald A. Arif, Yik Khoon Ee
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Publication number: 20110204328Abstract: A symmetrical quantum well active layer provides enhanced internal quantum efficiency. The quantum well active layer includes an inner (central) layer and a pair of outer layers sandwiching the inner layer. The inner and outer layers have different thicknesses and bandgap characteristics. The outer layers are relatively thick and include a relatively low bandgap material, such as InGaN. The inner layer has a relatively lower bandgap material and is sufficiently thin to act as a quantum well delta layer, e.g., comprising approximately 6 ? or less of InN. Such a quantum well structure advantageously extends the emission wavelength into the yellow/red spectral regime, and enhances spontaneous emission. The multi-layer quantum well active layer is sandwiched by barrier layers of high bandgap materials, such as GaN.Type: ApplicationFiled: December 15, 2010Publication date: August 25, 2011Applicant: Lehigh UniversityInventors: Nelson Tansu, Hongping Zhao, Guangyu Liu, Gensheng Huang