Patents by Inventor Soham Pathak

Soham Pathak 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: 20130182996
    Abstract: An apparatus for providing releasable attachment between a fiber connector and an opto-electronic assembly, the opto-electronic assembly utilizing an interposer substrate to support a plurality of opto-electronic components that generates optical output signals and receives optical input signals. An enclosure is used to cover the interposer substrate and includes a transparent region through which the optical output and input signals pass unimpeded. A magnetic connector component is attached to the lid and positioned to surround the transparent region, with a fiber connector for supporting one or more optical fibers magnetically attached to the connector component by virtue of a metallic component contained in the fiber connector. This arrangement provides releasable attachment of the fiber connector to the enclosure in a manner where the optical output and input signals align with the optical fibers in the connector.
    Type: Application
    Filed: January 9, 2013
    Publication date: July 18, 2013
    Inventors: Kalpendu Shastri, Soham Pathak, John Fangman, Vipulkumar Patel, Kishor Desai, Ravinder Kachru
  • Publication number: 20130183008
    Abstract: An apparatus for providing self-aligned optical coupling between an opto-electronic substrate and a fiber array, where the substrate is enclosed by a transparent lid such that the associated optical signals enter and exit the arrangement through the transparent lid. The apparatus takes the form of a two-part connectorized fiber array assembly where the two pieces uniquely mate to form a self-aligned configuration. A first part, in the form of a plate, is attached to the transparent lid in the area where the optical signals pass through. The first plate includes a central opening with inwardly-tapering sidewalls surrounding its periphery. A second plate is also formed to include a central opening and has a lower protrusion with inwardly-tapering sidewalls that mate with the inwardly-tapering sidewalls of the first plate to form the self-aligned connectorized fiber array assembly. The fiber array is then attached to the second plate in a self-aligned fashion.
    Type: Application
    Filed: January 9, 2013
    Publication date: July 18, 2013
    Inventors: Kalpendu Shastri, Soham Pathak, Utpal Chakrabarti, Vipulkumar Patel, Bipin Dama, Ravinder Kachru, Kishor Desai
  • Publication number: 20130101250
    Abstract: An opto-electronic assembly is provided comprising a substrate (generally of silicon or glass) for supporting a plurality of interconnected optical and electrical components. A layer of sealing material is disposed to outline a defined peripheral area of the substrate. A molded glass lid is disposed over and bonded to the substrate, where the molded glass lid is configured to create a footprint that matches the defined peripheral area of the substrate. The bottom surface of the molded glass lid includes a layer of bonding material that contacts the substrate's layer of sealing material upon contact, creating a bonded assembly. In one form, a wafer level assembly process is proposed where multiple opto-electronic assemblies are disposed on a silicon wafer and multiple glass lids are molded in a single sheet of glass that is thereafter bonded to the silicon wafer.
    Type: Application
    Filed: October 19, 2012
    Publication date: April 25, 2013
    Inventors: Kishor Desai, Ravinder Kachru, Vipulkumar Patel, Bipin Dama, Kalpendu Shastri, Soham Pathak
  • Patent number: 8363995
    Abstract: A set of planar, two-dimensional optical devices is able to be created in a sub-micron surface layer of an SOI structure, or within a sub-micron thick combination of an SOI surface layer and an overlying polysilicon layer. Conventional masking/etching techniques may be used to form a variety of passive and optical devices in this SOI platform. Various regions of the devices may be doped to form the active device structures. Additionally, the polysilicon layer may be separately patterned to provide a region of effective mode index change for a propagating optical signal.
    Type: Grant
    Filed: March 8, 2011
    Date of Patent: January 29, 2013
    Inventors: Prakash Gothoskar, Margaret Ghiron, Robert Keith Montgomery, Vipulkumar Patel, Kalpendu Shastri, Soham Pathak, Katherine A. Yanushefski
  • Publication number: 20120280344
    Abstract: A wafer scale implementation of an opto-electronic transceiver assembly process utilizes a silicon wafer as an optical reference plane and platform upon which all necessary optical and electronic components are simultaneously assembled for a plurality of separate transceiver modules. In particular, a silicon wafer is utilized as a “platform” (interposer) upon which all of the components for a multiple number of transceiver modules are mounted or integrated, with the top surface of the silicon interposer used as a reference plane for defining the optical signal path between separate optical components. Indeed, by using a single silicon wafer as the platform for a large number of separate transceiver modules, one is able to use a wafer scale assembly process, as well as optical alignment and testing of these modules.
    Type: Application
    Filed: May 3, 2012
    Publication date: November 8, 2012
    Applicant: LIGHTWIRE LLC
    Inventors: Kalpendu Shastri, Vipulkumar Patel, Mark Webster, Prakash Gothoskar, Ravinder Kachru, Soham Pathak, Rao V. Yelamarty, Thomas Daugherty, Bipin Dama, Kaushik Patel, Kishor Desai
  • Publication number: 20110216997
    Abstract: A set of planar, two-dimensional optical devices is able to be created in a sub-micron surface layer of an SOI structure, or within a sub-micron thick combination of an SOI surface layer and an overlying polysilicon layer. Conventional masking/etching techniques may be used to form a variety of passive and optical devices in this SOI platform. Various regions of the devices may be doped to form the active device structures. Additionally, the polysilicon layer may be separately patterned to provide a region of effective mode index change for a propagating optical signal.
    Type: Application
    Filed: March 8, 2011
    Publication date: September 8, 2011
    Applicant: LIGHTWIRE, INC.
    Inventors: Prakash Gothoskar, Margaret Ghiron, Robert Keith Montgomery, Vipulkumar Patel, Kalpendu Shastri, Soham Pathak, Katherine A. Yanushefski
  • Patent number: 7929814
    Abstract: A set of planar, two-dimensional optical devices is able to be created in a sub-micron surface layer of an SOI structure, or within a sub-micron thick combination of an SOI surface layer and an overlying polysilicon layer. Conventional masking/etching techniques may be used to form a variety of passive and optical devices in this SOI platform. Various regions of the devices may be doped to form the active device structures. Additionally, the polysilicon layer may be separately patterned to provide a region of effective mode index change for a propagating optical signal.
    Type: Grant
    Filed: April 23, 2004
    Date of Patent: April 19, 2011
    Assignee: Lightwire, Inc.
    Inventors: Prakash Gothoskar, Margaret Ghiron, Robert Keith Montgomery, Vipulkumar Patel, Kalpendu Shastri, Soham Pathak, Katherine A. Yanushefski
  • Patent number: 7587106
    Abstract: An arrangement for providing optical crossovers between waveguides formed in an SOI-based structure utilize a patterned geometry in the SOI structure that is selected to reduce the effects of crosstalk in the area where the signals overlap. Preferably, the optical signals are fixed to propagate along orthogonal directions (or are of different wavelengths) to minimize the effects of crosstalk. The geometry of the SOI structure is patterned to include predetermined tapers and/or reflecting surfaces to direct/shape the propagating optical signals. The patterned waveguide regions within the optical crossover region may be formed to include overlying polysilicon segments to further shape the propagating beams and improve the coupling efficiency of the crossover arrangement.
    Type: Grant
    Filed: June 12, 2008
    Date of Patent: September 8, 2009
    Assignee: Lightwire, Inc.
    Inventors: David Piede, Prakash Gothoskar, Margaret Ghiron, Robert Keith Montgomery, Vipulkumar Patel, Soham Pathak, Kalpendu Shastri, Katherine A. Yanushefski
  • Patent number: 7440703
    Abstract: An electro-optic modulator arrangement for achieving switching speeds greater than 1 Gb/s utilizes pre-emphasis pulses to accelerate the change in refractive index of the optical waveguide used to form the electro-optic modulator. In one embodiment, a feedback loop may be added to use a portion of the modulated optical output signal to adjust the magnitude and duration of the pre-emphasis pulses, as well as the various reference levels used for modulated. For free carrier-based electro-optic modulators, including silicon-based electro-optic modulators, the pre-emphasis pulses are used to accelerate the movement of free carriers at the transitions between input signal data values.
    Type: Grant
    Filed: February 22, 2006
    Date of Patent: October 21, 2008
    Assignee: SiOptical, Inc.
    Inventors: Kalpendu Shastri, Prakash Gothoskar, Margaret Ghiron, Vipulkumar Patel, Robert Keith Montgomery, Soham Pathak, Katherine A. Yanushefski
  • Publication number: 20080253713
    Abstract: An arrangement for providing optical crossovers between waveguides formed in an SOI-based structure utilize a patterned geometry in the SOI structure that is selected to reduce the effects of crosstalk in the area where the signals overlap. Preferably, the optical signals are fixed to propagate along orthogonal directions (or are of different wavelengths) to minimize the effects of crosstalk. The geometry of the SOI structure is patterned to include predetermined tapers and/or reflecting surfaces to direct/shape the propagating optical signals. The patterned waveguide regions within the optical crossover region may be formed to include overlying polysilicon segments to further shape the propagating beams and improve the coupling efficiency of the crossover arrangement.
    Type: Application
    Filed: June 12, 2008
    Publication date: October 16, 2008
    Inventors: David Piede, Prakash Gothoskar, Margaret Ghiron, Robert Keith Montgomery, Vipulkumar Patel, Soham Pathak, Kalpendu Shastri, Katherine A. Yanushefski
  • Patent number: 7358585
    Abstract: A silicon-based IR photodetector is formed within a silicon-on-insulator (SOI) structure by placing a metallic strip (preferably, a silicide) over a portion of an optical waveguide formed within a planar silicon surface layer (i.e., “planar SOI layer”) of the SOI structure, the planar SOI layer comprising a thickness of less than one micron. Room temperature operation of the photodetector is accomplished as a result of the relatively low dark current associated with the SOI-based structure and the ability to use a relatively small surface area silicide strip to collect the photocurrent. The planar SOI layer may be doped, and the geometry of the silicide strip may be modified, as desired, to achieve improved results over prior art silicon-based photodetectors.
    Type: Grant
    Filed: November 17, 2004
    Date of Patent: April 15, 2008
    Assignee: SiOptical, Inc.
    Inventors: Vipulkumar Patel, Margaret Ghiron, Prakash Gothoskar, Robert Keith Montgomery, Soham Pathak, David Piede, Kalpendu Shastri, Katherine A. Yanushefski
  • Patent number: 7298949
    Abstract: An SOI-based photonic bandgap (PBG) electro-optic device utilizes a patterned PBG structure to define a two-dimensional waveguide within an active waveguiding region of the SOI electro-optic device. The inclusion of the PBG columnar arrays within the SOI structure results in providing extremely tight lateral confinement of the optical mode within the waveguiding structure, thus significantly reducing the optical loss. By virtue of including the PBG structure, the associated electrical contacts may be placed in closer proximity to the active region without affecting the optical performance, thus increasing the switching speed of the electro-optic device. The overall device size, capacitance and resistance are also reduced as a consequence of using PBGs for lateral mode confinement.
    Type: Grant
    Filed: January 24, 2005
    Date of Patent: November 20, 2007
    Assignee: SiOptical, Inc.
    Inventors: Prakash Gothoskar, Margaret Ghiron, Robert Keith Montgomery, Vipulkumar Patel, Soham Pathak, David Piede, Kalpendu Shastri, Katherine A. Yanushefski
  • Patent number: 7269809
    Abstract: Computer-aided design (CAD) tools are used to perform the integrated design, verification and layout of electrical and optical components in a monolithic, silicon-based electro-optic chip. Separate top-level behavioral logic designs are prepared for the three different types of elements included within the final, silicon-based monolithic structure: (1) digital electronic integrated circuit elements; (2) analog/mixed signal electronic integrated circuit elements; and (3) opto-electronic elements (including passive and active optical elements). Once the behavioral logic design is completed, the results are combined and co-simulated. A physical layout design is developed and verified for each different type of element in the circuit. The separate physical layouts are then co-verified, to assess the properties of the overall physical design.
    Type: Grant
    Filed: June 22, 2005
    Date of Patent: September 11, 2007
    Assignee: SiOptical, Inc.
    Inventors: Kalpendu Shastri, Soham Pathak, Prakash Gothoskar, Paulius Mosinskis, Bipin Dama
  • Patent number: 7187837
    Abstract: An arrangement for actively controlling, in two dimensions, the manipulation of light within an SOI-based optical structure utilizes doped regions formed within the SOI layer and a polysilicon layer of a silicon-insulator-silicon capacitive (SISCAP) structure. The regions are oppositely doped so as to form an active device, where the application of a voltage potential between the oppositely doped regions functions to modify the refractive index in the affected area and alter the properties of an optical signal propagating through the region. The doped regions may be advantageously formed to exhibit any desired “shaped” (such as, for example, lenses, prisms, Bragg gratings, etc.), so as to manipulate the propagating beam as a function of the known properties of these devices. One or more active devices of the present invention may be included within a SISCAP formed, SOI-based optical element (such as, for example, a Mach-Zehnder interferometer, ring resonator, optical switch, etc.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: March 6, 2007
    Assignee: SiOptical, Inc.
    Inventors: Prakash Gothoskar, Margaret Ghiron, Robert Keith Montgomery, Vipulkumar Patel, Kalpendu Shastri, Soham Pathak, Katherine A. Yanushefski
  • Patent number: 7113676
    Abstract: A planar optical isolator is formed within the silicon surface layer of an SOI structure. A forward-directed signal is applied to an input waveguiding section of the isolator and thereafter propagates through a non-reciprocal waveguide coupling region into an output waveguide section. A rearward-directed signal enters via the output waveguide section and is thereafter coupled into the non-reciprocal waveguide structure, where the geometry of the structure functions to couple only a small amount of the reflected signal into the input waveguide section. In one embodiment, the non-reciprocal structure comprises an N-way directional coupler (with one output waveguide, one input waveguide and N?1 isolating waveguides).
    Type: Grant
    Filed: December 6, 2004
    Date of Patent: September 26, 2006
    Inventors: David Piede, Margaret Ghiron, Prakash Gothoskar, Robert Keith Montgomery, Vipulkumar Patel, Kalpendu Shastri, Soham Pathak, Katherine A. Yanushefski, Harvey Wagner
  • Patent number: 7109739
    Abstract: A wafer-level testing arrangement for opto-electronic devices formed in a silicon-on-insulator (SOI) wafer structure utilizes a single opto-electronic testing element to perform both optical and electrical testing. Beam steering optics may be formed on the testing element and used to facilitate the coupling between optical probe signals and optical coupling elements (e.g., prism couplers, gratings) formed on the top surface of the SOI structure. The optical test signals are thereafter directed into optical waveguides formed in the top layer of the SOI structure. The opto-electronic testing element also comprises a plurality of electrical test pins that are positioned to contact a plurality of bondpad test sites on the opto-electronic device and perform electrical testing operations. The optical test signal results may be converted into electrical representations within the SOI structure and thus returned to the testing element as electrical signals.
    Type: Grant
    Filed: March 8, 2005
    Date of Patent: September 19, 2006
    Assignee: SiOptical, Inc.
    Inventors: Prakash Gothoskar, Margaret Ghiron, Robert Keith Montgomery, Vipulkumar Patel, Kalpendu Shastri, Soham Pathak, David Piede, Katherine A. Yanushefski
  • Publication number: 20060140645
    Abstract: An electro-optic modulator arrangement for achieving switching speeds greater than 1 Gb/s utilizes pre-emphasis pulses to accelerate the change in refractive index of the optical waveguide used to form the electro-optic modulator. In one embodiment, a feedback loop may be added to use a portion of the modulated optical output signal to adjust the magnitude and duration of the pre-emphasis pulses, as well as the various reference levels used for modulated. For free carrier-based electro-optic modulators, including silicon-based electro-optic modulators, the pre-emphasis pulses are used to accelerate the movement of free carriers at the transitions between input signal data values.
    Type: Application
    Filed: February 22, 2006
    Publication date: June 29, 2006
    Inventors: Kalpendu Shastri, Prakash Gothoskar, Margaret Ghiron, Vipulkumar Patel, Robert Montgomery, Soham Pathak, Katherine Yanushefski
  • Patent number: 7065301
    Abstract: An electro-optic modulator arrangement for achieving switching speeds greater than 1 Gb/s utilizes pre-emphasis pulses to accelerate the change in refractive index of the optical waveguide used to form the electro-optic modulator. In one embodiment, a feedback loop may be added to use a portion of the modulated optical output signal to adjust the magnitude and duration of the pre-emphasis pulses, as well as the various reference levels used for modulated. For free carrier-based electro-optic modulators, including silicon-based electro-optic modulators, the pre-emphasis pulses are used to accelerate the movement of free carriers at the transitions between input signal data values.
    Type: Grant
    Filed: May 10, 2004
    Date of Patent: June 20, 2006
    Assignee: SiOptical, Inc.
    Inventors: Kalpendu Shastri, Prakash Gothoskar, Margaret Ghiron, Vipulkumar Patel, Robert Keith Montgomery, Soham Pathak, Katherine A. Yanushefski
  • Patent number: 7058261
    Abstract: An arrangement for achieving and maintaining high efficiency coupling of light between a multi-wavelength optical signal and a relatively thin (e.g., sub-micron) silicon optical waveguide uses a prism coupler in association with an evanescent coupling layer. A grating structure having a period less than the wavelengths of transmission is formed in the coupling region (either formed in the silicon waveguide, evanescent coupling layer, prism coupler, or any combination thereof) so as to increase the effective refractive index “seen” by the multi-wavelength optical signal in the area where the beam exiting/entering the prism coupler intercepts the waveguide surface (referred to as the “prism coupling surface”).
    Type: Grant
    Filed: September 7, 2004
    Date of Patent: June 6, 2006
    Assignee: SiOptical, Inc.
    Inventors: Margaret Ghiron, Prakash Gothoskar, Robert Keith Montgomery, Vipulkumar Patel, Soham Pathak, Kalpendu Shastri, Katherine A. Yanushefski
  • Patent number: 7020364
    Abstract: A trapezoidal shaped single-crystal silicon prism is formed and permanently attached to an SOI wafer, or any structure including a silicon optical waveguide. In order to provide efficient optical coupling, the dopant species and concentration within the silicon waveguide is chosen such that the refractive index of the silicon waveguide is slightly less than that of the prism coupler (refractive index of silicon?3.5). An intermediate evanescent coupling layer, disposed between the waveguide and the prism coupler, comprises a refractive index less than both the prism and the waveguide. In one embodiment, the evanescent coupling layer comprises a constant thickness. In an alternative embodiment, the evanescent coupling layer may be tapered to improve coupling efficiency between the prism and the waveguide. Methods of making the coupling arrangement are also disclosed.
    Type: Grant
    Filed: September 23, 2003
    Date of Patent: March 28, 2006
    Assignee: SiOptical Inc.
    Inventors: Margaret Ghiron, Prakash Gothoskar, Robert Keith Montgomery, Vipulkumar Patel, Soham Pathak, Kalpendu Shastri, Katherine A. Yanushefski