Patents by Inventor Atul Mathur

Atul Mathur 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).

  • Publication number: 20040033004
    Abstract: A photonic integrated circuits (PICs), also referred to as opto-electronic integrated circuits (OEICs), and more particularly to a PIC in the form of an optical receiver PIC or RxPIC for use in an optical transport networks. Also, an optical transmitter PIC (TxPIC) is also disclosed in conjunction with an RxPIC in an optical transport network. The chip is cast from an InP wafer and is made from Group III-V elemental materials in the InGaAsP/InP regime with fabrication accomplished through selective metalorganic vapor phase epitaxy (MOVPE) or also known as metalorganic chemical vapor deposition (MOCVD). Integrated on the chip, starting at the input end which is coupled to receive multiplexed optical data signals from an optical transport network is an optical amplifier, an optical demultiplexer, and a plurality of on-chip photodiodes (PDs) each to receive a demultiplexed data signal from the AWG DEMUX for optical-to-electrical signal conversion.
    Type: Application
    Filed: October 8, 2002
    Publication date: February 19, 2004
    Inventors: David F. Welch, Radhakrishnan L. Nagarajan, Fred A. Kish, Mark J. Missey, Vincent G. Dominic, Atul Mathur, Frank H. Peters, Charles H. Joyner, Richard P. Schneider, Ting-Kuang Chiang
  • Publication number: 20030095737
    Abstract: A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated on the same chip.
    Type: Application
    Filed: October 8, 2002
    Publication date: May 22, 2003
    Inventors: David F. Welch, Vincent G. Dominic, Fred A. Kish, Mark J. Missey, Radhakrishnan L. Nagarajan, Atul Mathur, Frank H. Peters, Robert B. Taylor, Matthew L. Mitchell, Alan C. Nilsson, Stephen G. Grubb, Richard P. Schneider, Charles H. Joyner, Jonas Webjorn, Drew D. Perkins
  • Publication number: 20030081878
    Abstract: A monolithic photonic integrated circuit (PIC) chip comprises an array of modulated sources providing a plurality of channel signals of different wavelengths and an optical combiner coupled to receive the channel signals and produce a combined output of the channel signals. The arrays of modulated sources are formed as ridge waveguides to enhance the output power from the respective modulated sources so that the average output power from the sources is approximately 2 to 4 times higher than in the case of comparable arrays of modulated sources formed as buried waveguides.
    Type: Application
    Filed: October 8, 2002
    Publication date: May 1, 2003
    Inventors: Charles H. Joyner, Fred A. Kish, Frank H. Peters, Atul Mathur, David F. Welch, Andrew G. Dentai, Damien Lambert, Richard P. Schneider, Mark J. Missey
  • Publication number: 20020097480
    Abstract: A Raman optical amplifier for amplifying an optical signal propagating in an optical fiber associated with an optical communications system. The amplifier includes a first Raman pump source including a first pump laser coupled to the fiber to provide first order Raman pump light for amplifying the optical signal, and a second Raman pump source including a second pump laser coupled to the fiber to provide second order Raman pump light for amplifying the first order Raman pump light. The first and second order Raman pump light is introduced into the fiber in either a co-propagating or counter-propagating direction relative to the propagation direction of the optical signal in the fiber. The second pump laser may include first and second pump laser elements that generate the second order Raman pump light, where a center wavelength of the light generated by the first laser element is different than the center wavelength of the light generated by the second laser element.
    Type: Application
    Filed: August 9, 2001
    Publication date: July 25, 2002
    Inventors: Vincent G. Dominic, Mehrdad Ziari, Atul Mathur
  • Publication number: 20010053168
    Abstract: A semiconductor laser has a waveguide modifying layer to increase output power. Specifically, the laser includes a p-doped cladding layer adjacent to a first side of an active layer. An n-doped cladding layer is positioned on a second side of the active layer. The waveguide modifying layer is disposed between the n-doped cladding layer and the active layer, where the modifying layer reduces an extent by which an optical mode confined by the active layer extends into the p-doped cladding layer.
    Type: Application
    Filed: May 10, 2001
    Publication date: December 20, 2001
    Inventor: Atul Mathur
  • Patent number: 6080140
    Abstract: A system and method for percutaneous access to a blood vessel is disclosed. The system according to the present invention includes a flexible guide wire for guiding the system to a desired position in a blood vessel; a tubular member having a lumen sized to slidingly receive the guide wire; an introducer having a lumen sized to slidingly receive the tubular member and a distal section including a S-shaped curve for assisting in positioning the system in the blood vessel; and a sheath having a lumen sized to slidingly receive the introducer, wherein the sheath provides access to the blood vessel after the system has been advanced to the desired position in the blood vessel.
    Type: Grant
    Filed: November 4, 1998
    Date of Patent: June 27, 2000
    Assignee: Iowa-India Investments Company, Ltd.
    Inventors: M. J. Swaminathan, Atul Mathur