North American Philips Corporation

Nanocrystals Technology LP

Other

Nanocrystal Imaging Corporation

U.S. Philips Corporation

Philips Electronics N.a. Corporation

Nan Crystal Imaging Corporation

Rameshwar N Bhargava

Vishal Chhabra

Dennis Gallagher

Avner A Shaulov

Nikhil R Taskar

Donald R Dorman

Samuel P Herko

Bharati S Kulkarni

John V Veliadis

Nikhil Taskar

Walter K Zwicker

Jacqueline Racz

Brian J Fitzpatrick

William N Osborne

Aleksey Yekimov

Dagobert M De Leeuw

Paul J Patt

Adosh Mehta

Efim T Goldburt

Pedro Tasaico

Bharail Kulkarni

Alfred E Milch

Neeta Pandit

Haranath Divi

Roger Delano

The present application is directed to the preparation and use of a class of nanoparticles that contain a single Quantum Confined dopant. A QCA nanocrystal comprises of a plurality of host atoms in a nanocrystal of a size of less than 10 nm with a single atom of a dopant (or activator). This single QCA dopant, when confined, becomes polarized and creates a large magnetic-moment in a nanosize host that contains atoms of unpaired spins. The quantum confined atom (QCA) which is now pinned, triggers the alignment of the host atoms resulting in nanosize magnetic domain. Engineering of nanomagnets based on QCA nanoparticles can be used in different applications such as: sensors, drug delivery, bio-tagging, cell/DNA tagging, magnetic memories and others.

Quantum confined atom (QCA) based nanomagnets

The present application is directed to the preparation and use of a class of nanoparticles called Quantum Confined Atoms or QCA's. A QCA is a particle of material comprising a plurality of host atoms in a nanoparticle of a size of less than 10 nm with a single atom of a dopant (or activator) confined within. The QCA's have unique luminescent and optical properties and thus can act as a very efficient nanophosphor which generate polarized light and can operate as a laser and a nanomagnet. An anti-agglomeration coating surrounding the nanoparticles can prevent clumping and loss of the enhanced properties.

Self-aligning QCA based nanomaterials

A photonic structure for &ldquo;white&rdquo; light generation by phosphors under the excitation of a LED. The photonic structure mounts the LED and an optically transparent matrix having dispersed therein phosphors which will emit light under the excitation of the radiation of the LED. The transparent matrix may include nanoparticles for matching the index of refraction of the material of the matrix to that of the light generating phosphors. The matrix material may be readily formed by molding and formed into a variety of shapes including lenses for focusing the emitted light. A large number of the photonic structures may be arranged on a substrate to provide even illumination or other purposes. The phosphors dispersed in the matrix are preferably nanocrystalline.

Nanocrystalline based phosphors and photonic structures for solid state lighting

An X-ray imaging system utilizing a pixelated X-ray source and a X-ray imaging detector operated synchronously. The imaging system may be used in industrial and medical applications. The X-ray source and X-ray detector are synchronized such that a corresponding area of the X-ray detector is activated when the corresponding area of the X-ray source is emitting X-rays. Synchronized and adaptive emission and detection of the X-rays results in scatter rejection, improved image quality, and optimum exposure and dose reduction.

X-ray imaging system incorporating pixelated X-ray source and synchronized detector

A microchannel phosphor screen for converting radiation, such as X-rays, into visible light. The screen includes a planar surface, which can be formed from glass, silicon or metal, which has etched therein a multiplicity of closely spaced microchannels having diameters of the order of 40 microns or less. Deposited within each of the microchannels is a multiplicity of phosphors which emit light when acted upon by radiation. The dimensions of the microchannel and the phosphors and the relationship between the microchannels and the phosphors is optimized so that the light output compares favorably with lower resolution non microchannel based scintillation screens. A photomultiplier can be integrated with the X-ray detector so as to provide an enhanced output for use with low level X-ray of for cine or fluoroscopy applications.

High resolution high output microchannel based radiation sensor

A composite phosphor screen for converting radiation, such as X-rays, into visible light. The screen includes a planar surface, which can be formed from glass, silicon or metal, which has etched therein a multiplicity of closely spaced microchannels having diameters of the order of 10 microns or less. Deposited within each of the microchannels is a multiplicity of phosphors which emit light when acted upon by radiation. A photomultiplier, which may be microchannel based, is integrated with the X-ray detector so as to provide an enhanced output for use with low level X-ray of for cine or fluoroscopy applications. The walls of the microchannels and/or the substrate surfaces include dielectric stack based light reflective coatings.

Microchannel high resolution x-ray sensor having an integrated photomultiplier

A composite phosphor screen for converting radiation, such as X-rays, into visible light. The screen includes a planar surface, which can be formed from glass, silicon or metal, which has etched therein a multiplicity of closely spaced microchannels having diameters of the order of 10 microns or less. Deposited within each of the microchannels is a multiplicity of phosphors which emit light when acted upon by radiation. The walls of the microchannels and/or the substrate surfaces include light reflective coatings so as to reflect the light emitted by the phosphors to the light collecting devices, such as film or an electronic detector. The coatings can be either radiation transparent or filtering/attenuating depending on the particular application.

Composite nanophosphor screen for detecting radiation having optically reflective coatings

Doped semiconductor nanoparticles of a size (<100 &angst;) which exhibit quantum effects. The nanoparticles are grown and doped within a polymer matrix.

Method of manufacturing quantum sized doped semiconductor particles

Doped encapsulated semiconductor nanoparticles of a size (&lt;100 .ANG.) which exhibit quantum effects. The nanoparticles are precipitated and coated with a surfactant by precipitation in an organometallic reaction. The luminescence of the particles may be increased by a further UV curing step.

Encapsulated quantum sized doped semiconductor particles and method of

A process for the production of metal oxide nanocrystals activated with a rare earth element, which are useful as phosphors. The nanocrystal oxides are produced by a micellar microemulsion process. In the process an aqueous solutions of the host and activator is prepared and added to a mixture of oil and a micelle forming surfactant and cosurfactant to form a first water in oil microemulsion. An aqueous solution of a hydroxide containing compound is added to a second mixture of oil and a micelle forming surfactant and cosurfactant to form a second water in oil microemulsion. The two microemulsions are added together which cause the micelle units to coalesce and decoalesce and to form a nanocrystalline hydroxide compound of the host and activator. The solution is washed and treated so as to remove byproducts. Thereafter the hydroxide compound is converted to an nanocrystalline activated oxide.

Microemulsion method for producing activated metal oxide nanocrystals

A composite phosphor screen for converting radiation, such as X-rays, into visible light. The screen includes a planar surface, which can be formed from glass, silicon or metal, which has etched therein a multiplicity of closely spaced nanochannels having diameters of the order of 5 microns or less. Deposited within each of the nanochannels is a multiplicity of nanocrystalline phosphors, having diameters of less than 100 nanometers and preferably less than 10 nanometers, which emit light when acted upon by radiation. The walls of the nanochannels are arranged to reflect the light emitted by the nanophoshors down the nanochannels to suitable light collecting device such as film or an electronic device. This minimizes light scattering and increases light collection efficiency.

Composite nanophosphor screen for detecting radiation

A process for the production of metal oxide nanocrystalline phosphors activated with a rare earth, line emitting, element. The nanocrystal oxides are produced by a sol-gel like process. The process begins with an n-butoxide solution of the host and activator which is first subject to acetolysis which will cause the pH of the solution to change from basic to acidic. This is followed by the addition of water in a hydrolysis step which forms a host/activator hydroxide solution. To the host/activator hydroxide solution, sodium hydroxide, which is very basic, is added, which will cause the precipitation of host oxide nanocrystals activated with the activator. The host/activator n-butoxide precursors may be synthesized by azeotropic distillation.

Method for producing rare earth activited metal oxide nanocrystals

Method of manufacturing encapsulated doped particles

Electronic displays including CRTs and projection TV (PTV), field emission displays (FED), plasma and electroluminescent (EL) displays, all of whom involve the use of luminescent materials (active displays) for the transfer of information to an audience. The phosphor material used in these displays comprises doped nanocrystals; tiny, separated particles of the order of 100 angstroms or less and thus exhibiting quantum-confined properties. These quantum-confined particles of certain luminescent materials when doped with an activator yield ultra-fast and efficient phosphors. The resultant displays will possess high brightness and high resolution. In addition, certain of the displays will exhibit digital control and increased gray scale.

Displays comprising doped nanocrystal phosphors

An efficient and ultrafast sensor for X-ray and UV radiation based on doped nanocrystals. These doped nanocrystals consist preferably of impurity-activator doped wide band gap II-VI semiconductors. They yield high efficiency and short recombination time radiation-sensitive phosphors which in response to radiation emit visible light easily detected by conventional sensors such as Si sensors. The combination of pulsed UV/X-ray sources with efficient and ultrafast sensors will yield sensors with increased signal to noise ratio. In a preferred embodiment, thin films of doped nanocrystals are used for generating visible radiation, which can be imaged with a conventional Si-based camera. Other applications also include the use of doped nanocrystals of piezoelectric materials to sense pressure, of pyroelectric materials to sense heat, and of ferroelectric materials to sense electric fields.

Growing community of inventors

Ossining, NY, United States of America

Rameshwar N Bhargava