Patents by Inventor John I. Thackara
John I. Thackara 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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Patent number: 6546163Abstract: A planar waveguide integrated optic switch suitable for use in optical cross-connect applications. A narrow trench in the planar waveguide core layer is filled with a liquid crystal material possessing positive birefringence. When held at a temperature a few degrees above the clearing point, the liquids crystal's isotropic refractive index is matched to that of the core layer allowing nearly complete optical transmission through the switch. When held at a temperature a few degrees below the clearing point, the liquid crystal's ordinary refractive index is lower than that of the core layer and both polarizations of the incident optical radiation are totally reflected from the trench. When coupled with planar waveguide beam expanding and refocusing elements, arrays of the switches can be used to form an optical cross-connect capable of fully interconnecting linear arrays of single- or multi-mode optical fibers with very low optical loss.Type: GrantFiled: May 24, 2001Date of Patent: April 8, 2003Inventor: John I. Thackara
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Publication number: 20020041726Abstract: A planar waveguide integrated optic switch suitable for use in optical cross-connect applications. A narrow trench in the planar waveguide core layer is filled with a liquid crystal material possessing positive birefringence. When held at a temperature a few degrees above the clearing point, the liquids crystal's isotropic refractive index is matched to that of the core layer allowing nearly complete optical transmission through the switch. When held at a temperature a few degrees below the clearing point, the liquid crystal's ordinary refractive index is lower than that of the core layer and both polarizations of the incident optical radiation are totally reflected from the trench. When coupled with planar waveguide beam expanding and refocusing elements, arrays of the switches can be used to form an optical cross-connect capable of fully interconnecting linear arrays of single- or multi-mode optical fibers with very low optical loss.Type: ApplicationFiled: May 24, 2001Publication date: April 11, 2002Inventor: John I. Thackara
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Patent number: 5640372Abstract: A rotationally symmetric timepiece wherein time information is displayed along an axis that is marked in 13 locations with axially symmetric markers. The 13 markers divide the axis into 12 sections of preferably equal length as well as mark the ends of the axis. Time information is displayed by one or more indicators which move along the axis at controlled rates. To display hour information, an indicator, which encircles the axis, is moved along the axis at a speed such that it travels the full length of the axis in a 12-hour period. At the end of this period, the indicator is preferably reset back to the first indicator. To display minute and second information, two additional indicators are used. The minute indicator is made to travel the length of the axis every hour before being reset, while the second indicator travels the length of the axis over a period of one minute before it is reset. The indicators are of different diameters so they do not interfere with each other as they travel along the axis.Type: GrantFiled: April 19, 1996Date of Patent: June 17, 1997Inventor: John I. Thackara
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Patent number: 5155617Abstract: Method and apparatus for electro-optically modulating the intensity of an incident light beam including a coupling prism with a high reflective index, a semiconductor substrate in optical contact with the coupling prism and having a conductive area formed therein, an organic electro-optic film formed on the substrate and covering at least a portion of the conductive area, and a transmission line disposed above the electro-optic film and cooperating with the conductive area to form electrodes for use in applying an electric field across the electro-optic film. Light directed through the substrate by the coupling prism couples with surface plasmons at the film-to-metal interface and is selectively reflected or absorbed depending upon whether or not an electric field is applied.Type: GrantFiled: June 13, 1991Date of Patent: October 13, 1992Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Olav Solgaard, John I. Thackara
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Patent number: 5071231Abstract: Digital data processing unit includes two SLMs assembled back-to-back with a common photoreceptor, to form a bidirectional spatial light modulator (BSLM) which facilitates the flow of data in the forward and reverse directions. An image can be written from the left side of the BSLM and read from the left or right side of the unit. An image can also be written from the right side and read from the right or left or both sides of the unit. The photoreceptor sums the light image intensities when data is concurrently written from both sides into the photoreceptor.Type: GrantFiled: May 24, 1990Date of Patent: December 10, 1991Assignee: The United States of America as Represented by the Secretary of the Air ForceInventors: David Armitage, John I. Thackara
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Patent number: 5007696Abstract: A three-dimensional electro-optic waveguide is formed as a channel in a structure made of an organic non-linear optical polymer. A poling electric field is maintained in a portion of the polymer structure defining the channel, and the polymer structure is heated above the glass-transition temperature to enable dipolar moieties of the polymer to become aligned by the poling field. Heating continues until the dipolar moieties are sufficiently aligned to produce a higher index of refraction in the channel portion than in adjacent cladding portions of the polymer structure for at least one polarization of optical radiation propagating through the channel. The poling field is maintained as the polymer structure is then cooled below glass-transition temperature, thereby preserving alignment of the dipolar moieties (and hence preserving the differential index of refraction) in the channel portion of the polymer structure. Guided modes of optical radiation of at least one polarization can be supported in the channel.Type: GrantFiled: January 8, 1990Date of Patent: April 16, 1991Assignee: Lockheed Missiles & Space Company, Inc.Inventors: John I. Thackara, George F. Lipscomb, Hyun-Nam Yoon, Ronald N. De Martino
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Patent number: 5006285Abstract: A three-dimensional electro-optic waveguide is formed as a channel in a structure made of an organic non-linear optical polymer. A poling electric field is maintained in a portion of the polymer structure defining the channel, and the polymer structure is heated above the glass-transition temperature to enable dipolar moieties of the polymer to become aligned by the poling field. Heating continues until the dipolar moieties are sufficiently aligned to produce a higher index of refraction in the channel portion than in adjacent cladding portions of the polymer structure for at least one polarization of optical radiation propagating through the channel. The poling field is maintained as the polymer structure is then cooled below glass-transition temperature, thereby preserving alignment of the dipolar moieties (and hence preserving the differential index of refraction) in the channel portion of the polymer structure. Guided modes of optical radiation of at least one polarization can be supported in the channel.Type: GrantFiled: July 28, 1988Date of Patent: April 9, 1991Assignee: Lockheed Missiles & Space Company, Inc.Inventors: John I. Thackara, George F. Lipscomb, Hyun-Nam Yoon, Ronald N. De Martino
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Patent number: 4826553Abstract: A method for transferring a dielectric mirror prepared on an optical flat replication substrate to a utilization device having a nonflat surface. In order to separate the replication substrate from the mirror after the mirror has been cemented to the device at room temperature and the cement allowed to cure over an extended time period, the composite assembly is inserted into a fixture which provides a buckling force to the center of the replication substrate to cause the replication substrate to be peeled from the mirror.Type: GrantFiled: June 18, 1987Date of Patent: May 2, 1989Assignee: The United States of America as represented by the Secretary of the Air ForceInventors: David Armitage, John I. Thackara
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Patent number: H1001Abstract: An optical quality film is transferred from a master optical surface to a condary substrate by means of a replication technique using a master optical surface as a mold.Type: GrantFiled: September 21, 1989Date of Patent: December 3, 1991Assignee: The United States of Amercia as represented by the Secretary of the ArmyInventor: John I. Thackara