Palo Alto Research Center Inc.

Xerox Corporation

Thomas Wunderer

Noble Marshall Johnson

Christopher L Chua

John E Northrup

Zhihong Yang

Brent Shawhan Krusor

Mark Teepe

Bowen Cheng

David Kalman Biegelsen

Michael A Kneissl

Jengping Lu

Joerg Martini

Robert Anthony Street

Palghat Srinivas Ramesh

David Mathew Johnson

Jeng Ping Lu

Anne Plochowietz

Kathryn F Murphy

Clifford F Knollenberg

Max Batres

Suk Choi

Jorg Jeschke

Ali Eshaghian Dorche

Farsane Tabataba-Vakili

A mask material is deposited on a substrate or growth template. The substrate or growth template is compatible with crystalline growth of a crystalline optical material. Patterned portions of the mask material are removed to expose one or more regions of the substrate or growth template. The one or more regions have target shapes of one or more optical components. The crystalline optical material is selectively grown in the one or more regions to form the one or more optical components.

Forming optical components using selective area epitaxy

Ink-based digital printing systems useful for ink printing include a rotatable charge-retentive reimageable surface layer configured to receive a layer of fountain solution. The fountain solution is carried to the charge retentive surface by a fog or mist including fountain solution aerosol particles, dispersed gas particles, and charge directors that impart charge to the fountain solution aerosol particles. The charge-retentive reimageable surface may be charged to a uniform potential, and selectively discharged using an ROS according to image data to form an electrostatic latent image. The charged fountain solution adheres to portions of the charge-retentive reimageable surface according to the electrostatic latent image to form a fountain solution image thereon. The fountain solution image can be partially transferred to an imaging blanket, where the fountain solution image is inked. The resulting ink image may be transferred to a print substrate.

Charged particle generation, filtration, and delivery for digital offset printing applications

A transistor includes a first layer comprising a group III-nitride semiconductor. A second layer comprising a group III-nitride semiconductor is disposed over the first layer. A third layer comprising a group III-nitride semiconductor is disposed over the second layer. An interface between the second layer and the third layer form a polarization heterojunction. A fourth layer comprising a group III-nitride semiconductor is disposed over the third layer. An interface between the third layer and the fourth layer forms a pn junction. A first electrical contact pad is disposed on the fourth layer. A second electrical contact pad is disposed on the third layer. A third electrical contact pad is electronically coupled to bias the polarization heterojunction.

Polarization controlled transistor

Based on evaporation of fountain solution from a rotating blanket cylinder to create an image that may be inked and printed, a digitally addressable heater array at or just below the blanket surface evaporates deposited fountain solution and forms a fountain solution latent image on the surface. The heater array has controllable heating elements (e.g., field effect transistors, thin film transistors) that provide a transient heat pattern on the surface to evaporate the fountain solution. Heat is generated by current flow in the heating elements, and power developed by the heating circuit is the product of source-drain voltage and current in the channel. Current may be supplied along data lines by an external voltage controlled by digital electronics to provide the desired heat at heating elements addressed by a specific gate line. The heater array may include a current return line that may be a 2-dimensional mesh.

Matrix-addressed heat image forming device

An optical device has a first optical layer with a first dispersion response as a first function of wavelength. A second optical layer has a second dispersion response as a function of wavelength that is different than the first function. A separating layer is located between the first and second optical layers and has a lower refractive index than the first layer and the second layer. A thickness of the separating layer is selected such that the first and second dispersion responses combine to create an anomalous dispersion about a target wavelength. The anomalous dispersion results in the optical device emitting a wideband coherent optical output about the target wavelength in response to an optical input at the target wavelength.

Multi-layer optical device exhibiting anomalous dispersion

A laser includes an active region surrounded by first and second waveguide layers. Two or more mask openings are formed within a dielectric layer on a surface parallel to the active region. A refractive grating is formed on the dielectric mask openings and includes three-dimensional grating features spaced apart in the light-propagation direction of the laser. The refractive grating provides modulation of a real part of the effective refractive index of the laser and modulation of the imaginary part is provided by modulation of the current flow through the mask openings.

Index and gain coupled distributed feedback laser

An ultraviolet (UV) radiation emitting device includes an epitaxial heterostructure comprising an AlGaInN active region. The AlGaInN active region includes one or more quantum well structures with Al content greater than about 50% and having a non-c-plane crystallographic growth orientation. The AlGaInN active region is configured to generate UV radiation in response to excitation by an electron beam generated by an electron beam pump source.

Electron beam pumped non-c-plane UV emitters

An edge emitting structure includes an active region configured to generate radiation in response to excitation by a pumping beam incident on the structure. A front facet of the edge emitting structure is configured to emit the radiation generated by the active region. A metallic reflective coating disposed on at least one of the front and rear facets of the edge emitting structure. The metallic reflective coating is configured to reflect the radiation generated by the active region.

Pumped edge emitters with metallic coatings

A method of thinning a bulk aluminum nitride substrate includes providing a bulk aluminum nitride (AlN) substrate with at least one epitaxially grown group-III-nitride layer on a first side of the substrate, applying a slurry having a high pH to a second side of the substrate opposite the first side, chemical mechanically polishing the second side of the substrate using the slurry to remove at least a portion of the substrate, resulting in a thinned layer with a thickness less than 50 microns, and bonding the epitaxial layer to a non-native substrate. A device has at least one active zone in a layer of epitaxial Group-III-nitride material, the epitaxial Group-III-nitride layer having a defect density of less than or equal to 10/cm.

Thin film and substrate-removed group III-nitride based devices and method

A light emitting device includes a p-side heterostructure having a short period superlattice (SPSL) formed of alternating layers of AlGaN doped with a p-type dopant and AlGaN doped with the p-type dopant, where x&#x2264;x&#x2264;0.9. Each layer of the SPSL has a thickness of less than or equal to about six bi-layers of AlGaN.

P-side layers for short wavelength light emitters

A vertical external cavity surface emitting laser (VECSEL) structure includes a heterostructure and first and second reflectors. The heterostructure comprises an active region having one or more quantum well structures configured to emit radiation at a wavelength, &#x3bb;, in response to pumping by an electron beam. One or more layers of the heterostructure may be doped. The active region is disposed between the first reflector and the second reflector and is spaced apart from the first reflector by an external cavity. An electron beam source is configured to generate the electron beam directed toward the active region. At least one electrical contact is electrically coupled to the heterostructure and is configured to provide a current path between the heterostructure and ground.

Electron beam pumped vertical cavity surface emitting laser

Light emitting devices having an enhanced degree of polarization, P, and methods for fabricating such devices are described. A light emitting device may include a light emitting region that is configured to emit light having a central wavelength, &#x3bb;, and a degree of polarization, P, where P&#x3e;0.006&#x3bb;&#x2212;b for 200 nm&#x2264;&#x3bb;&#x2264;400 nm, wherein b&#x2264;1.5.

Ultraviolet light emitting devices having compressively strained light emitting layer for enhanced light extraction

A device includes one or more reflector components. Each reflector component comprises layer pairs of epitaxially grown reflective layers and layers of a non-epitaxial material, such as air. Vias extend through at least some of the layers of the reflector components. The device may include a light emitting layer.

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Palo Alto, CA, United States of America

Thomas Wunderer