Patents by Inventor David K. Smith
David K. Smith 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: 20020094182Abstract: Disclosed is a single mode optical waveguide fiber designed for use in high performance telecommunication systems. The novel core profile design improves bending performance to provide enhanced resistance to adverse environments. Total dispersion over an extended wavelength window is maintained low by placing the zero dispersion wavelength above the upper limit of the operating window. In addition, cut off wavelength is increased to just below the operating window. Ease of manufacture is retained as is very low waveguide attenuation.Type: ApplicationFiled: January 22, 2002Publication date: July 18, 2002Inventor: David K. Smith
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Patent number: 6404965Abstract: Disclosed is a single mode optical waveguide fiber having a core refractive index profile in which the profile parameters are selected to provide an attenuation minimum. A set of profiles having the same general shape and dimensions is shown to have a group of profiles contained in a sub-set which exhibit a minimum of attenuation as compared to the remaining members of the set. The members of the sub-set have been found to have the lowest effective group index, ngeff, and the lowest change in &bgr;2 under waveguide fiber bending.Type: GrantFiled: July 3, 2001Date of Patent: June 11, 2002Assignee: Corning IncorporatedInventors: Peter C. Jones, Daiping Ma, David K. Smith
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Patent number: 6389208Abstract: Disclosed is a single mode optical waveguide fiber designed for use in high performance telecommunication systems. The novel core profile design improves bending performance to provide enhanced resistance to adverse environments. Total dispersion over an extended wavelength window is maintained low by placing the zero dispersion wavelength above the upper limit of the operating window. In addition, cut off wavelength is increased to just below the operating window. Ease of manufacture is retained as is very low waveguide attenuation.Type: GrantFiled: June 4, 1998Date of Patent: May 14, 2002Assignee: Corning IncorporatedInventor: David K. Smith
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Publication number: 20010046359Abstract: Disclosed is a single mode optical waveguide fiber having a core refractive index profile in which the profile parameters are selected to provide an attenuation minimum. A set of profiles having the same general shape and dimensions is shown to have a group of profiles contained in a sub-set which exhibit a minimum of attenuation as compared to the remaining members of the set. The members of the sub-set have been found to have the lowest effective group index, ngeff, and the lowest change in &bgr;2 under waveguide fiber bending.Type: ApplicationFiled: July 3, 2001Publication date: November 29, 2001Inventors: Peter C. Jones, Daiping Ma, David K. Smith
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Patent number: 6324327Abstract: Disclosed is a segmented core optical waveguide fiber having low total dispersion slope and negative total dispersion over an extended wavelength window. A wavelength window of particular interest is that in the range of about 1500 nm to 1600 nm. The waveguide fibers in accordance with the invention also have cabled cut off wavelength below about 1480 nm and attenuation at 1550 nm of less than 0.22 dB/km. Mode field diameter is maintained essentially at the nominal value for dispersion shifted waveguide fiber, i.e., 7.7 &mgr;m to 8.7 &mgr;m. Embodiments having a center segment and a first and a second annular segment are discussed in detail.Type: GrantFiled: October 24, 2000Date of Patent: November 27, 2001Assignee: Corning IncorporatedInventors: James B. Herring, David K. Smith
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Patent number: 6317551Abstract: The invention is directed to a single mode optical waveguide fiber profile that provides relatively large effective area while limiting macrobend loss. The large effective area results from configuring the core of the waveguide fiber to shift propagated light power away from the waveguide center. Macrobend loss, as measured by pin array or 20 mm mandrel testing, is maintained low by means of a power-limiting index depression surrounding the central core region of the waveguide. In addition, low attenuation is achieved and cut off wavelength is controlled to provide a telecommunications operating window in the wavelength range of about 1250 nm to 1700 nm.Type: GrantFiled: June 27, 2000Date of Patent: November 13, 2001Assignee: Corning IncorporatedInventors: Brian E. Mitchell, David K. Smith
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Patent number: 6282354Abstract: Disclosed is a single mode optical waveguide fiber having a core refractive index profile in which the profile parameters are selected to provide an attenuation minimum. A set of profiles having the same general shape and dimensions is shown to have a group of profiles contained in a sub-set which exhibit a minimum of attenuation as compared to the remaining members of the set. The members of the sub-set have been found to have the lowest effective group index, ngeff, and the lowest change in &bgr;2 under waveguide fiber bending.Type: GrantFiled: August 17, 2000Date of Patent: August 28, 2001Assignee: Corning IncorporatedInventors: Peter C. Jones, Daiping Ma, David K. Smith
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Patent number: 6134367Abstract: Disclosed is a single mode optical waveguide fiber having a core refractive index profile in which the profile parameters are selected to provide an attenuation minimum. A set of profiles having the same general shape and dimensions is shown to have a group of profiles contained in a sub-set which exhibit a minimum of attenuation as compared to the remaining members of the set. The members of the sub-set have been found to have the lowest effective group index, n.sub.geff, and the lowest change in .beta..sup.2 under waveguide fiber bending.Type: GrantFiled: September 2, 1998Date of Patent: October 17, 2000Assignee: Corning IncorporatedInventors: Peter C. Jones, Daiping Ma, David K. Smith
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Patent number: 6031956Abstract: Disclosed is a single mode optical waveguide fiber having a segmented core design. In particular, the core comprises three segments, each having characteristic dimensions and refractive index profile. By proper choice of index profile in each segment, a waveguide fiber is made which has a mode field diameter of about 9.5, low, positive total dispersion over the operating window 1530 nm to 1565 nm as well as effective area greater than 60 .mu.m.sup.2.Type: GrantFiled: October 14, 1998Date of Patent: February 29, 2000Assignee: Corning IncorporatedInventors: Ming-Jun Li, Yanming Liu, Daiping Ma, David K. Smith
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Patent number: 5748824Abstract: A single mode optical waveguide fiber having a positive total dispersion is disclosed. The novel waveguide fiber has a core region comprising three distinct segments. Studies of this novel waveguide, wherein properties are calculated as various ones of the core region parameters are changed, show that the waveguide satisfies the requirements of a fiber in a high bit rate, long regenerator spacing system. The novel waveguide design is relatively simple to manufacture and maintains its functional properties at tight tolerances when the core region parameters are varied over a prescribed range. This high performance waveguide limits self phase modulation and four wave mixing, facilitates wavelength division multiplexing, and is compatible with optical amplifiers.Type: GrantFiled: November 17, 1995Date of Patent: May 5, 1998Assignee: Corning IncorporatedInventor: David K. Smith
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Patent number: 5740793Abstract: A dry powder inhalation device comprising a housing defining a chamber in communication with a patient port in the form of a mouthpiece or nasal adaptor, and an elongate carrier bearing a powdered medicament, the device being constructed and arranged such that areas of predetermined size of the elongate carrier may sequentially be exposed within the chamber, the device comprising one or more air inlets such that when a patient inhales through the patient port an air flow is established from the air inlet(s) to the patient port through the chamber such that particles of the powdered medicament of respirable size from said exposed area of the elongate carrier are entrained within the air flow.Type: GrantFiled: June 6, 1995Date of Patent: April 21, 1998Assignee: Astra AktiebolagInventors: Peter D. Hodson, David K. Smith, David J. Velasquez, Anthony C.L. Wass, Clyde D. Calhoun
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Patent number: 5619984Abstract: A dry powder inhalation device comprising a housing defining a chamber in communication with a patient port in the form of a mouthpiece or nasal adaptor, and an elongate carrier bearing a powdered medicament, the device being constructed and arranged such that areas of predetermined size of the elongate carrier may sequentially be exposed within the chamber, the device comprising one or more air inlets such that when a patient inhales through the patient port an air flow is established from the air inlet(s) to the patient port through the chamber such that particles of the powdered medicament of respirable size from said exposed area of the elongate carrier are entrained within the air flow.Type: GrantFiled: May 8, 1995Date of Patent: April 15, 1997Assignee: Astra AktiebolagInventors: Peter D. Hodson, David K. Smith, David J. Velasquez, Anthony C. L. Wass
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Patent number: 5553185Abstract: A single mode optical waveguide fiber having low, non-zero dispersion over a pre-selected wavelength range is disclosed. The refractive index profile of the core is characterized in that the core includes a plurality of distinct regions, each having an index profile, and a radius or width. By adjusting the index profile sizes and shapes of the plurality of core regions, a waveguide fiber may be made having a set of properties tailored for a high performance telecommunication system. In particular, dispersion slope can be maintained less than 0.05 ps/nm.sup.2 -km and absolute magnitude of total dispersion maintained in the range of 0.5 to 3.5 ps/nm-km over a pre-selected wavelength range. The zero dispersion wavelength is outside the pre-selected wavelength range and the cut off wavelength and mode field diameter are controlled to target values.Type: GrantFiled: December 27, 1994Date of Patent: September 3, 1996Assignee: Corning IncorporatedInventors: A. Joseph Antos, Evelyn M. DeLiso, Yanming Liu, Mark A. Newhouse, David K. Smith, Carlton M. Truesdale
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Patent number: 5482032Abstract: The present invention relates to a device for dislodging powder carried on the surface of a flexible sheet material. The device incorporates a resettable impactor including a head for striking the sheet material, wherein the head comprises an elongate striking surface which is curved in both planes orthoganol to the plan of the sheet material.Type: GrantFiled: July 12, 1994Date of Patent: January 9, 1996Assignee: Astra AktiebolagInventors: David K. Smith, Peter D. Hodson, Anthony C. L. Wass
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Patent number: 5483612Abstract: An compound core optical waveguide fiber designed for high data rate or single channel or WDM systems which may include optical amplifiers. The waveguide is characterized by a core having two or three regions wherein the refractive index can be varied. The relative size of the regions may also be varied. By adjusting these variables, the desired mode field diameter, zero dispersion wavelength, dispersion slope and cut off wavelength were obtained. The optical properties are chosen to limit non-linear effects while maintaining low attenuation and acceptable bend performance. In addition, the residual stress within the waveguide is maintained at a low level to limit stress induced birefringence. The low residual stress in the uncoated waveguide, together with a dual coating system having selected moduli and glass transition temperatures results in low polarization mode dispersion.Type: GrantFiled: October 17, 1994Date of Patent: January 9, 1996Assignee: Corning IncorporatedInventors: Daniel Gallagher, Daniel A. Nolan, David K. Smith, J. Richard Toler, Grant P. Watkins
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Patent number: 5361319Abstract: Disclosed is a family of dispersion compensating optical fibers that are adapted for use with conventional single-mode transmission fibers that are optimized for zero dispersion operation at a wavelength in the range from 1290 nm to 1330 nm to form a transmission link suitable for low dispersion operation in the 1520-1565 nm wavelength window. The dispersion compensating fibers are capable of providing a dispersion more negative than -20 ps/nm-km and attenuation less than 1 dB/km at wavelengths in the 1520-1565 nm region. Certain of the dispersion compensating fibers also exhibit a dispersion versus wavelength relationship having a negative slope in the 1520-1565 nm region, to compensate for the dispersion versus wavelength slope of the transmission fiber. The dispersion compensating fiber can be advantageously combined with a fiber amplifier to form a compensator that is adapted to overcome attenuation introduced into the system by the dispersion compensating fiber.Type: GrantFiled: February 4, 1992Date of Patent: November 1, 1994Assignee: Corning IncorporatedInventors: A. Joseph Antos, Michael G. Blankenship, Douglas W. Hall, Edward F. Murphy, David K. Smith
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Patent number: 5347998Abstract: An inhalation device for use with a pressurized aerosol canister. The device involves an electromechanical mechanism for applying a priming force to the aerosol canister prior to or at the start of inhalation. The device also involves a blocking mechanism. The electromechanical mechanism electromechanically applies to the aerosol canister a priming force sufficient to actuate the aerosol canister, and the blocking mechanism prevents the priming force from actuating the aerosol canister until inhalation is detected.Type: GrantFiled: December 23, 1992Date of Patent: September 20, 1994Assignee: Minnesota Mining and Manufacturing CompanyInventors: Peter D. Hodson, Eric A. Baum, David K. Smith, Anton Kuepper, Matthew J. Wilby
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Patent number: 5278931Abstract: An optical waveguide fiber with improved bend loss performance while maintaining cutoff wavelength, .lambda..sub.c, and zero dispersion wavelength, .lambda..sub.0, in practical operating ranges. The fiber includes an inner core region with a refractive index delta higher than the rest of the core and a reduced diffusion tail at the core/cladding interface. Optionally, a ring at the outer portion of the core is provided to compensate for increased .lambda..sub.0 which results from the higher inner core refractive index delta. This ring also contributes to the reduced diffusion tail at the core/cladding interface.Type: GrantFiled: December 31, 1992Date of Patent: January 11, 1994Assignee: Corning IncorporatedInventors: A. Joseph Antos, David K. Smith
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Patent number: 5069204Abstract: An inhalation device comprising:(i) a breath-actuated inhaler comprising a medicament reservoir mounted within a housing which comprises a mouthpiece and breath-actuation means which prevents dispensing from the reservoir until a patient inhales through the mouthpiece, and,(ii) a protective casing surrounding the breath actuated inhaler, the casing comprising a body portion and a movable cover which may be displaced to allow a patient access to the mouthpiece to use the breath-actuated inhaler while it is within the casing, the breath-actuated inhaler being removable from the protective casing and operable outside the casing.Type: GrantFiled: August 17, 1990Date of Patent: December 3, 1991Assignee: Riker Laboratories, Inc.Inventors: David K. Smith, Anthony C. L. Wass
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Patent number: 4361080Abstract: Disclosed is a real floor for a lauter tun comprising a plurality of elongated linear troughs, each trough extending unobstructed across the bottom of the vessel and each forming a relatively shallow upward opening V-shape. The elements making up the floor are shaped to provide the lauter tun floor with a circular profile.Type: GrantFiled: July 18, 1980Date of Patent: November 30, 1982Assignee: Henry Balfour & Company Ltd.Inventors: David K. Smith, Nigel Harlow, Samuel W. Maxfield