Patents Examined by Stephen W. Barns
  • Patent number: 5016960
    Abstract: A hybrid optical Y-junction device includes a 1.times.N optical fiber coupler connected to N waveguide structures fabricated on a single substrate. When the waveguide structure is a semiconductor optical amplifier, the hybrid Y-junction device is operable as either a modulator or lossless power divider. A nonblocking optical switch is constructed by coupling M.times.1 optical fiber couplers to the outputs of the waveguide structures in the hybrid Y-junction. The switch is also effective as a wavelength division multiplexer when periodic gratings are integrated into the waveguide amplifiers.
    Type: Grant
    Filed: December 22, 1989
    Date of Patent: May 21, 1991
    Assignee: GTE Laboratories Incorporated
    Inventors: Elliot Eichen, Paul Melman
  • Patent number: 5015053
    Abstract: An electro-optical modulating system has a light source for producing a carrier wave. The carrier wave is polarized by a polarizer so as to adjust the power of the carrier wave in transverse electric (TE) polarization mode and in transverse magnetic (TM) polarization mode. In addition to a polarizer the electro optical modulating includes at least one set of electrodes for adjusting phase biases of the TE and TM polarization mode components of the carrier wave. The electrodes allow independent control of the phase biases of the respective TE polarization mode components and TM polarization mode components. Multiple sets of electrodes for adjusting the phase biases may be used. A modulating means is also included for modulating the carrier wave so as to encode information. The modulating system preferably also includes an interferometric modulator comprised of at least two branches. The modulation and phase bias adjustment take place on both of the respect branches.
    Type: Grant
    Filed: September 8, 1989
    Date of Patent: May 14, 1991
    Assignee: Massachusetts Institute of Technology
    Inventor: Leonard M. Johnson
  • Patent number: 5015064
    Abstract: An electronic printer employing a bundle of optical fibers organizes the fiber ends in first and second faces of the bundle in a linear array and in an annulus or ring array respectively. A spinning prism is operative to image a linear array of light sources onto a segment of the annulus and move the image through a succession of positions to cover the entire area of the annulus in one revolution providing the pixels for a linear segment of a photosensitive medium optically coupled to the first face of the bundle.
    Type: Grant
    Filed: April 5, 1990
    Date of Patent: May 14, 1991
    Assignee: Photon Imaging Corp.
    Inventors: Robert H. Detig, Michael Sidey, Li-Shin Wang
  • Patent number: 5013110
    Abstract: The core (4), of plastically deformable material, is supported and fastened in the hollow cylindrical outer part (2), of relatively hard material, on a supporting shoulder (6). Moreover, especially good results can be aimed for if the core (4) is slightly mushroom shaped and exhibits a disc (7) with a shank (8). The disc (7) can accommodate temperature determined dilatations especially well.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: May 7, 1991
    Assignee: Diamond S.A.
    Inventor: Silvio Marazzi
  • Patent number: 5013117
    Abstract: This invention is the method for manufacturing the fiber type coupler by extending at least two optical fibers having coatings thereof removed, along an optical axis while fusing the optical fibers to form a coupler member, is characterized by a step of adding a tension to the coupler member along the optical axis before the coupler member is fixed to a protective member.
    Type: Grant
    Filed: October 13, 1989
    Date of Patent: May 7, 1991
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Masumi Fukuma
  • Patent number: 5005937
    Abstract: In optical branching equipment which is supplied with an optical signal of a first wavelength band from a trunk line terminal equipment via a trunk line cable and is inserted in the trunk line, the optical signal is normally provided to the trunk line cable after being bypassed from a branching circuit to branch line terminal equipment connected to a branch line cable, and when trouble develops in the branch line, the optical signal is delivered to the trunk line cable via a short circuit. In the short circuit there is inserted an optical limiter amplifier which is capable of amplifying light of the first and second wavelength bands. Normally the optical limiter amplifier is saturated by control light of the second wavelength supplied from the branch line terminal equipment via the branch line cable, and consequently, the optical signal of the first wavelength band is suppressed.
    Type: Grant
    Filed: April 10, 1990
    Date of Patent: April 9, 1991
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kazuo Aida, Shigendo Nishi, Kiyoshi Nakagawa
  • Patent number: 5002353
    Abstract: Non-linear distortion of a modulated light carrier wave arising from optical modulator nonlinearity of significantly reduced by offsetting a dominant cubic term of intermodulation distortion in transverse electric (TE) mode with a dominant cubic term of intermodulation distortion in transverse magnetic (TM) mode. The offset is achieved by adjusting the magnitude of the components of light in TE mode and TM mode to compensate for the differing response of components of the light wave in TM mode versus components in TE mode to a given voltage level applied to the carrier wave during modulation. The adjustments to the relative magnitude can be performed by a polarizer or polarization-preserving fiber. This method may be used in a modulating system and an electro-optical communication system.
    Type: Grant
    Filed: April 25, 1989
    Date of Patent: March 26, 1991
    Assignee: Massachusetts Institute of Technology
    Inventor: Leonard M. Johnson
  • Patent number: 5002361
    Abstract: This invention provides polymeric thin film optical waveguide media which exhibit nonlinear optical response, and which have utility as an optical waveguide component in all-optical and electrooptical light switch and light modulator devices.
    Type: Grant
    Filed: January 23, 1990
    Date of Patent: March 26, 1991
    Assignee: Hoechst Celanese Corp.
    Inventors: Ronald N. DeMartino, Hyun-Nam Yoon, James B. Stamatoff
  • Patent number: 4997255
    Abstract: An optical fiber splice retainer comprises a base member having a groove extending along a reference surface of the base member, resilient biasing means carried by the base member, and three gripping members which are urged by the resilient biasing means into a gripping position against the reference surface to span the groove at respective gripping locations along the groove. The gripping members are movable against the urging of the resilient biasing means away from the reference surface to permit insertion of optical fibers into the grooves. The gripping members are permitted to close on the inserted optical fibers to clamp the optical fibers in the groove with the fibers in axial alignment. A jig is provided for holding the splice retainer and for urging the gripping members away from the reference surface as required during insertion and alignment of the optical fibers.
    Type: Grant
    Filed: December 7, 1989
    Date of Patent: March 5, 1991
    Assignee: Northern Telecom Limited
    Inventors: Helmut H. Lukas, Grant K. Pacey, Steve J. Lischynsky
  • Patent number: 4997246
    Abstract: An optical modulator [30] includes a waveguide region having, for radiation of a predetermined wavelength such as 1.3 microns, a variable optical transmittance characteristic. The optical transmittance characteristic is a function of a difference between an index of refraction of a first region [36] comprised of silicon having a first type of electrical conductivity and an index of refraction of a second adjacent region [34] comprised of an insulator such as a silicon dioxide. The modulator further includes a third region [38], also comprised of silicon, disposed adjacent to the first region. The third region has a second type of electrical conductivity for forming a p-n junction with the first region. Charge carriers are injected into the first region for varying the index of refraction thereof such that the optical transmittance characteristic of the waveguide region is varied.
    Type: Grant
    Filed: December 21, 1989
    Date of Patent: March 5, 1991
    Assignee: International Business Machines Corporation
    Inventors: Paul G. May, Subramanian S. Iyer
  • Patent number: 4995728
    Abstract: A compact configuration of a large number of splicing modules that enables each splicing module to be freely accessible is made by connecting each splicing module to a carrier with a pivotal connection so that the pivoting axis extends through the interior of the splicing module, parallel to the direction in which the light waveguide bundle is introduced into the splicing module. The pivoting axes of several splicing modules extend parallel to one another. Each splicing module has a hollow cylinder that is mounted to the carrier with U-sections. Light waveguides are led through the hollow cylinders to each splicing module. No excess length of the light waveguides is necessary since the hollow cylinders remain stationary during pivoting of a splicing module. The pivotal connection of the splicing modules enables them to be "leafed through" like a book. Each splicing module can be accessed in this manner so that the light waveguide splices located on it can be renewed or repaired.
    Type: Grant
    Filed: December 6, 1989
    Date of Patent: February 26, 1991
    Assignee: Siemens Aktiengesellschaft
    Inventor: Lothar Finzel
  • Patent number: 4983010
    Abstract: A system for connecting light waveguide buses and coaxial cable buses operating according to the token passing principle. The coaxial cable buses are connected with electrical terminal access devices. An opto-electrical converter is disposed between a terminal access device and a light waveguide bus.
    Type: Grant
    Filed: October 25, 1989
    Date of Patent: January 8, 1991
    Assignee: Licentia Patent-Verwaltungs-GmbH
    Inventor: Wolfgang Popp
  • Patent number: 4981338
    Abstract: The index of refraction of a liquid is measured using an optical fiber refractometer having a light transmitting optical fiber by immersing a portion of the optical fiber in the liquid and launching light into one end of the optical fiber at a selected non-zero launch angle with respect to the fiber axis. Light transmitted through the optical fiber is detected at the other end of the optical fiber and a determination is made of the index of refraction of the liquid in accordance with the detected light and the selected non-zero launch angle. By varying the launching angles of the light the range of the refractometer is increased. The light transmitting optical fiber is provided with a region having at least one tapered portion for further increasing the range of the refractometer. The tapered portion of the optical fiber is disposed between a refractive end of the optical fiber and the light source for providing single-ended operation.
    Type: Grant
    Filed: July 16, 1990
    Date of Patent: January 1, 1991
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Lloyd C. Bobb, Howard D. Krumboltz