International Business Machines Corporation

Fibera, Inc.

American Cyanamid Company

Cornell Research Foundation Inc.

David W Wang

John C Tsai

Kostas I Papathomas

William J Summa

Konstantinos I Papathomas

Eugene R Skarvinko

Ashit A Mehta

Frederick R Christie

Voya Rista Markovich

Jeffrey Donald Gelorme

Donald J Casey

Stephen Joseph Fuerniss

Patrick Robert Zippetelli

Leonard T Lehmann

Michael J Cibulsky

Ralph S Paonessa

Daniel R Draney

Carl E Diener

Deborah Lynn Dittrich

Robert Maynard Japp

George G Barclay

Mark David Poliks

Christopher Kemper Ober

William John Rudik

Peter K Jarrett

Charles Robert Davis

Jae M Park

Richard W Carpenter

Dalip K Kohli

Leroy N Chellis

Michael M Fisher

Walter Moreland Thomas

Joseph A Methe

Peter J Lueck

Robert J Cox

Lee P Springer

Jeanne L Courter

Pey Schuan Jian

Peiti Su

Edward J Bonafino

A system for tuning the wavelength of a beam from a tunable laser. A tunable etalon assembly includes a Fabry-Perot etalon with paired reflectors to filter the laser beam. The tunable etalon also includes a thermal unit to thermally adjust the separation of the paired responsive to an etalon tuning signal. A photodetector receives the laser beam after filtering the etalon and generates a detected signal based on intensity. A controller generates the etalon tuning signal, and receives the detected signal and generates a laser tuning signal based on it. Optionally, additional Fabry-Perot etalons, photodetectors, and one or more beamsplitters permit extending wavelength range and determining relative wavelength difference with a beam from a second laser.

Tunable wavelength locker, tunable wavelength spectrum monitor, and relative wavelength measurement system

An a thermal fiber Bragg grating assembly. A platform provides two attachment locations and has a first coefficient of thermal expansion. A stick provides two ends and has a second coefficient of thermal expansion. A fiber Bragg grating provides two ends and has effective third coefficient of thermal expansion. One stick end is fixed to one grating end, the other stick end is fixed to one attachment location, and the other grating end is fixed to the other attachment location. The stick has a same cross-section area along its length that is equal to or less than the cross-section area of the grating. And the coefficients and lengths between respective locations and ends are such that the assembly exhibits an effective overall coefficient of thermal expansion approaching zero.

Athermal fiber Bragg grating

A structure analysis and defect detection system in which a laser light source provides light via optical fiber to fiber Bragg gratings that change resonant frequency as stresses change in the structure. Light at the resonant frequencies of the fiber Bragg gratings is reflected and light of other frequencies is passed. The respective reflected light is directed through a Fabry-Perot interference filter or a fiber interferometer and detected by a photodetector. If the Fabry-Perot interference filter is used, the intensity of the reflected light indicates current stress at a fiber Bragg grating. If the fiber interferometer is used, a beat frequency due to heterodyne interference in the light indicates current stress at the respective fiber Bragg grating. Comparison data for the respective characteristic in the detected light over time permits stress analysis, and comparison of such data with pre-determined limit values permits defect or failure detection.

Structure analysis and defect detection system

Multi-dimensional optical gratings () of a background material () having a first refractive index and cells () of at least one different refractive index. The cells () may occupy two-dimensional or three-dimensional grids, defining the optical gratings as planar gratings () or cubical gratings (), and thus providing two or three sets of surface-to-surface separations, or thicknesses, and cell-to-cell separations. The respective sets of surface-to-surface separations and cell-to-cell separations used may particularly be selected according to Bragg's law to selectively scatter respective light wavelengths.

Multidimensional optical gratings

A multiplexing and de-multiplexing system that may both use the same wavelength division multiplexing (WDM) device. For multiplexing, light sources provide a plurality of light beams having different wavelengths and the WDM forms a single light beam. For de-multiplexing, a light source provides a light beam having a plurality of different light wavelengths and the WDM forms a plurality of output light beams each having respective of the wavelengths. The WDM devices may particularly be formed from optically multi-dimensional planar gratings and cubical gratings which may diffract single wavelengths, sets of wavelengths, and ranges of wavelengths each with respect to one optical dimension present. The gratings may be discrete or integrated in the multiplexing or the de-multiplexing devices. Complex embodiments of the multiplexing system, such as an interleaver, and complex embodiments of the de-multiplexing system, such as a de-interleaver, can be formed using blocks of the gratings.

Wavelength division multiplexing and de-multiplexing system

An interference filter ( ) and a process ( ) by which it may be fabricated. A substrate ( ) is provided and a working region ( ) is defined therein or thereupon. Relative to the horizontal substrate ( ), a plurality of vertical layers having differing refractive index are then constructed by applying material into the working region ( ) or altering material already in the working region ( ). Photo masking and etching processes may be used to selectively remove material in the working region ( ) for applying additional material having a differing refractive index. Photo masking and impurity doping processes may be used to selectively change material to have a differing refractive index.

Interference filter fabrication

An electronic package assembly where a low profile integrated circuit chip package is soldered to an organic (e.g., epoxy resin) substrate, e.g., a printed circuit board or card, the projecting conductive leads of the integrated circuit chip package and the solder which substantially covers these leads (and respective conductors on the substrate) having been substantially covered with ultraviolet photocured encapsulant material (e.g., polymer resin) to provide reinforcement for the solder-lead connections. The encapsulant material is dispensed about the solder and lead joints following solder reflow and solidification so as to substantially surround the solder and any portions of the leads not covered with solder.

Lead protective coating composition, process and structure thereof

A process ( ) to construct single- and multi-dimensional optical gratings ( ) of interlayers ( ) of differing refractive index, either in or atop a non-fiber substrate material ( ). The optical gratings ( ) may particularly be Bragg type gratings, and thus suitable for receiving a laser beam ( ) and forming there from one or more reflected beam portions ( ) having one or more narrow wavelengths and a passed beam portion ( ) of other wavelengths.

Optical grating fabrication

A frequency locker ( ) for working with external light sources or frequency locked light sources ( ) having integrated laser light sources ( ). The locker ( ) provides multi-channel frequency tuning and stabilization with common components, particularly including common beam splitters ( ), an interferometer ( ), and a processing circuit ( ). The locked light source ( ) integrates a light source ( ) and single channel frequency tuning and stabilization capabilities. The locked light source ( ) integrates multiple instances of the locked light source ( ) within a single housing ( ) to provide multi-channel capability. And the locked light source ( ) provides multi-channel frequency tuning and stabilization with common components, particularly including a single beam splitter ( ), an interferometer ( ), and a processing circuit ( ).

Frequency locker

A frequency processing system for detecting, tuning, or stabilizing light frequency or wavelength in a light beam produced by a light source. A grating block receives the light beam and may produce diffracted beams and a passed beam. The diffracted beams are received by respective detectors which produce measurement signals that are communicated to a processor. The processor then produces control signals that are communicated to the light source where they are usable for detecting, tuning, or stabilizing the light frequency or wavelength. The grating blocks particularly employ planar or cubical gratings, or gradient versions of these, to produce the diffracted beams.

Frequency detection, tuning and stabilization system

An electronic package assembly where a low profile integrated circuit chip package is soldered to an organic (e.g., epoxy resin) substrate, e.g., a printed circuit board or card, the projecting conductive leads of the integrated circuit chip package and the solder which substantially covers these leads (and respective conductors on the substrate) having been substantially covered with ultraviolet photocured encapsulant material (e.g., an epoxy resin or a cyanate with a photoinitiator and silica) to provide reinforcement for the solder-lead connections. The encapsulant material is dispensed about the solder and lead joints following solder reflow and solidification so as to substantially surround the solder and any portions of the leads not covered with solder.

Encapsulating a solder joint with a photo cured epoxy resin or cyanate

Solder interconnection encapsulant, encapsulated structure and method for its fabrication and use, whereby the gap created by solder connections between a carrier substrate and a semiconductor device is filled with a composition obtained from curing a preparation containing a cycloaliphatic polyepoxide and/or curable cyanate ester or prepolymer thereof; filler, e.g., an aluminum nitride or aluminum oxide filler, having a maximum particle size of 31 microns.

Solder interconnection structure and process for making

A thermally stable photoimaging composition and a method of using the same, especially on circuit boards as a solder mask is provided. The composition includes a polymerizable resin or resin system, a cationic photoinitiator, a solvent, and an optically transparent ceramic filler. Preferably, the composition has a coefficient of thermal expansion of about 28-40 ppm/.degree.C., which closely matches the coefficient of thermal expansion of the solder used on the circuit board components.

Thermally stable photoimaging composition

A thermally stable photoimaging composition and a method of using the same, especially on circuit boards as a solder mask is provided. The composition includes a polymerizable resin or resin system, a cationic photoinitiator, a solvent, and an optically transparent ceramic filler. Preferably, the composition has a coefficient of thermal expansion of about 28-40 ppm/.degree. C., which closely matches the coefficient of thermal expansion of the solder used on the circuit board components.

Solder interconnection structure

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Vestal, NY, United States of America

David W Wang