Patents Examined by Yisun Song
  • Patent number: 5613029
    Abstract: A hinge adapter mounts to a fiber optic splice tray, such as the Keptel LL-2400.RTM. splice tray, and provides a hinging capability to these splice trays. The hinge adapters have a U-shaped member mounted at each corner of the splice tray. The U-shaped member has a central portion having a pair of arms depending therefrom, with the distal ends of the arms having an aperture and the ends of the central portion having a protrusion. When stacking the splice trays, the apertures formed in the arms of one hinge adapter receive protrusions in the central portion of another hinge adapter. When the hinge adapters on one side of a desired splice tray are separated from the hinge adapters above that splice tray, an installer or lineman can pivot the upper splice trays away from the desired tray and readily gain access to the desired splice tray. The U-shaped members are mounted to a side of the splice tray by brackets which are inserted into an area of the splice trays.
    Type: Grant
    Filed: May 10, 1995
    Date of Patent: March 18, 1997
    Assignee: Lucent Technologies Inc.
    Inventors: Denis E. Burek, George E. Mock
  • Patent number: 5608750
    Abstract: A semiconductor laser device is provided which is designed to prevent end surface optical damage, thereby permitting an increase in the output of the semiconductor laser. To achieve this, an active layer at the light emitting end surface portion of the semiconductor laser device is recessed inwardly by a distance between 50 nm and 300 nm (depending on the amount of etching) from the end surfaces of the crystal layers lying on both sides of the active layer. The recess serves to improve the heat dissipation of the active layer portion. This results in improving the amount of light output of the semiconductor laser which is possible without causing optical damage. A method for making the device is also provided. This method permits achieving the above-noted advantages simply by adding an etching step to the conventional semiconductor laser fabrication process, without requiring special equipment or technique.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: March 4, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Shinichi Nakatsuka, Kenji Uchida, Misuzu Sagawa, Satoru Kikuchi
  • Patent number: 5608746
    Abstract: A method for avoiding damage to the eyes when using high-power lasers in the eye-transmissible spectral region is provided. By adding a laser or a radiation in the visible spectral region, the intensity of the radiation is increased as a function of time in the shape of a ramp from zero to higher values which lead to a conscious or reflex-type closing of the eyelids This therefore prevents the eyes from being damaged by the subsequent high-power laser beam.
    Type: Grant
    Filed: July 11, 1994
    Date of Patent: March 4, 1997
    Assignee: Deutsche Aerospace AG
    Inventor: Gunthard Born
  • Patent number: 5606570
    Abstract: A semiconductor laser is formed with an array of a small number (two to ten) antiguide elements each containing a portion of the active region of the semiconductor laser. Interelement structures between the antiguide elements are formed to have a relatively high interelement loss coefficient (at least 100 cm.sup.-1), providing excellent discrimination between the resonant in-phase mode and the unwanted nonresonant modes. Lateral reflectors may be utilized at the edge of the array to reflect light back to the array, but are not necessary when the antiguide elements are sufficiently wide and the effective index step between the antiguide elements and interelement structures is sufficiently large. Because only a relatively small number (10 or less) of antiguide elements are utilized, fabrication tolerances are relatively large and practical devices may be produced with satisfactory yields.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: February 25, 1997
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Dan Botez, Charles A. Zmudzinski, Luke J. Mawst
  • Patent number: 5604757
    Abstract: A system for controlling the operation of multiple laser diodes in a noise free and efficient manner. The system includes a control module that generates control signals to control and regulate the multiple laser diodes, and an input/output module that allows control parameters to be selected and set by a user. Each individual laser diode is stabilized and regulated by its own individual laser diode driver module that includes current, power, and temperature regulation systems to ensure the operating parameters of each laser diode are accurately maintained. Each laser diode driver module also measures key operating parameters to allow the control module to monitor system operation and switch malfunctioning diodes off. All analog-to-digital conversions of each diode's operating parameters are performed by digital circuitry within the control module, which is physically separated from the laser diode driver modules to minimize interference that is typically caused by the digital switching.
    Type: Grant
    Filed: May 10, 1994
    Date of Patent: February 18, 1997
    Assignee: E-Tek Dynamics, Inc.
    Inventors: Yungfu F. Liang, Jing J. Pan
  • Patent number: 5604762
    Abstract: A semiconductor optical device includes a n-clad layer, an active layer formed on the n-type clad, a carrier reservoir layer formed on the active layer, and a p-clad layer formed on the carrier reservoir layer. The thickness of the carrier reservoir layer is in a range where the oscillation wavelength shifts in a short wavelength direction with increasing driving current.
    Type: Grant
    Filed: November 23, 1994
    Date of Patent: February 18, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Motoyasu Morinaga, Nobuo Suzuki, Masaki Tohyama
  • Patent number: 5602863
    Abstract: A surface-emitting LD array includes a plurality of surface-emitting LDs respectively including secondary diffraction gratings produced at the same pitch. These LDs are radially arranged on the substrate with a prescribed point on the substrate as the center of the radial arrangement so that the secondary diffraction gratings face to the center point. In this structure, the laser oscillation regions of the adjacent surface-emitting LDs are spaced apart from each other, so that the respective surface-emitting LDs are operated individually with high stability. As the result, when these surface-emitting LDs are oscillated with the same driving current, a high power laser light comprising a plurality of laser lights that are emitted from the respective LDs and have the same phase and the same wavelength is output stably in a prescribed direction.
    Type: Grant
    Filed: July 19, 1994
    Date of Patent: February 11, 1997
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Takushi Itagaki
  • Patent number: 5602866
    Abstract: In a semiconductor laser, lower layers (an optical waveguide and a carrier blocking layer), which are exposed to air after they have been etched to form diffraction gratings until crystals are regrown, are formed of a five-element AlGaInAsP-based compound semiconductor material. Thus, a semiconductor laser is obtained which has a high yield and the oscillation wavelength range of 740-1000 nm and maintains a high reliability over a long period of time.
    Type: Grant
    Filed: October 19, 1994
    Date of Patent: February 11, 1997
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Toshiaki Fukunaga
  • Patent number: 5600667
    Abstract: A semiconductor laser device having an active layer, a pair of cladding layers interposing the active layer and a multi-quantum barrier provided between one of the pair of cladding layers and the active layer is provided. The multi-quantum barrier includes barrier layers and well layers being alternated with each other. Thickness, energy band gap, or impurity concentration of at least one of the barrier layers and well layers in the multi-quantum barrier changes with the distance from the active layer, thereby providing a stable function of reflecting carriers overflowing from the active layer back to the active layer.
    Type: Grant
    Filed: April 5, 1994
    Date of Patent: February 4, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Isao Kidoguchi, Kiyoshi Ohnaka, Hideto Adachi, Satoshi Kamiyama, Masaya Mannou, Takeshi Uenoyama
  • Patent number: 5592502
    Abstract: A semiconductor laser element includes: a semiconductor laminated structure for emitting a laser light, including an active layer interposed between a first cladding layer of a first-conductivity type and a second cladding layer of a second-conductivity type, the first cladding layer and the semiconductor layer having lower refractive indices than that of the active layer; and a current light confining means including a stripe-shaped semiconductor layer of the second-conductivity type formed on a surface of the second cladding layer on a side opposite to the active layer, for confining a laser driving current and the laser light in a region of the active layer corresponding to the stripe-shaped semiconductor layer, wherein the refractive index of the first cladding layer is larger than that of the second cladding layer in the semiconductor laminated structure, and the semiconductor laminated structure includes at least one semiconductor layer of the first-conductivity type having a lower refractive index than
    Type: Grant
    Filed: October 21, 1994
    Date of Patent: January 7, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Mitsuhiro Matsumoto, Ken Ohbayashi
  • Patent number: 5590141
    Abstract: A laser system uses a broad-area high-power diode laser in cooperation with a nonimaging concentrator, or an unstable resonator semiconductor laser, to end pump a relatively thin, solid-state, highly doped lasant. The laser system generates a very high density of excited ions in the lasant mode volume to produce high peak power pulses having comparable magnitudes over a wide range of pulse repetition frequencies.
    Type: Grant
    Filed: June 20, 1994
    Date of Patent: December 31, 1996
    Assignee: Electro Scientific Industries, Inc.
    Inventors: Brian Baird, Richard DeFreez, Yunlong Sun
  • Patent number: 5590145
    Abstract: A light-emitting apparatus capable of selecting polarization direction of a light outputted therefrom includes a semiconductor laser and an optical amplifying device. The semiconductor laser is capable of selectively changing a direction of polarization plane of the output light to one of two orthogonal directions by controlling an excited state. The optical amplifying device amplifies the output light from the semiconductor laser. The optical amplifying device has amplification factors with respect to polarized light components in two orthogonal directions.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: December 31, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventor: Jun Nitta
  • Patent number: 5588077
    Abstract: An especially compact optical rotary joint for use with fiber optic cables is set forth including three embodiments capable of transferring two data streams each carried on a separate optical fiber. The rotary joint is constructed with a stationary portion and a relatively rotating portion. The two optical fiber channels are arranged in-line along the same rotational axis. Isolation of one channel from the other is achieved through a novel application of gradient index rod lenses of suitable pitch. A pair of lenses is arranged adjacent each other on each side of the rotational interface and a second pair of axially aligned lenses is arranged outboard of the first pair. An optical signal from one of the outboard lenses can be directed to one of the other lenses depending on the pitch selection. Losses due to crosstalk or overlap of the signal paths is within acceptable limits. Both channels are bidirectional, i.e., each can carry signals in either direction.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: December 24, 1996
    Assignee: Focal Technologies, Inc.
    Inventor: Shane H. Woodside
  • Patent number: 5583880
    Abstract: A semiconductor comprising: a current blocking layer made of gallium nitride type compound; an active layer comprising a semiconductor made of gallium nitride type compound; an upper cladding layer and lower cladding layer made of gallium nitride compound wherein the active layer is provided between the upper and lower clad layers; wherein a stripe groove functioning as a current path is formed in said current blocking layer within at least one layer of the upper and lower clad layers.
    Type: Grant
    Filed: September 20, 1995
    Date of Patent: December 10, 1996
    Assignee: Rohm Co., Ltd.
    Inventor: Yukio Shakuda
  • Patent number: 5581572
    Abstract: A wavelength-tunably distributed Bragg reflector laser having selectively activated virtual diffraction gratings including a semiconductor guide layer (4) between two other semiconductor confinement layers (6,8) of opposite dopings. A passive part of the laser has sections (SC1, SC2, SC3), each of which include a periodic arrangement (A) spatially modulating the distribution of the carriers or the electric field in the guide layer when a current is injected into the p-n junction formed by the two other layers or where the junction is reverse biased to create a diffraction grating. Each section has an effective optical index cooperating with the corresponding diffraction grating in order to give a predetermined Bragg wavelength for the section.
    Type: Grant
    Filed: February 2, 1995
    Date of Patent: December 3, 1996
    Assignee: France Telecom
    Inventors: Franck Delorme, Christophe Kazmierski
  • Patent number: 5579332
    Abstract: A light source including a gaseous medium which is excited to a light-emitting state by means of a microwave electromagnetic field, wherein the electromagnetic field is generated by circularly polarised microwave radiation. A preferred form of the invention is a laser.
    Type: Grant
    Filed: October 24, 1994
    Date of Patent: November 26, 1996
    Assignee: United Kingdom Atomic Energy Authority
    Inventors: Michael R. Osborne, Keith H. Bayliss
  • Patent number: 5579424
    Abstract: An arrangement for optically coupling a planar optical waveguide and an optical fiber comprises forming a planar optical waveguide on a surface of the substrate, forming a trench-like depression in the surface of the substrate leading from an end face of the planar waveguide to an edge of the substrate, forming a second holder part having a fiber secured between two planar surfaces lying in a common plane, assembling the separate holder part on a pair of planar surfaces lying on each side of the depression of said substrate so that the fiber is placed in the depression with play and the fiber will be arranged with the axis of the fiber being aligned with the axis of the planar waveguide.
    Type: Grant
    Filed: November 21, 1995
    Date of Patent: November 26, 1996
    Assignee: Siemens Aktiengesellschaft
    Inventor: Hartmut Schneider
  • Patent number: 5577061
    Abstract: A mid-IR laser is provided having novel AlAs/Al.sub.x Ga.sub.1-x Sb or InAs/Al.sub.x Ga.sub.1-x Sb superlattice cladding regions. The arsenide layers of the n-type cladding region are doped n-type, utilizing silicon, and may be used with conventional active region materials, such as InAs.sub.z Sb.sub.1-z and In.sub.w Ga.sub.1-w As.sub.y Sb.sub.1-y. The novel cladding regions can be deposited without the use of Group VI elements, such as Te, which are not preferred source materials for MBE growth. Furthermore, the need for quaternary layers, such as Al.sub.x Ga.sub.1-x As.sub.y Sb.sub.1-y, used in the prior art devices, is eliminated; consequently, the need for precise control of two Group V fluxes (As and Sb) is eliminated.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: November 19, 1996
    Assignee: Hughes Aircraft Company
    Inventors: Thomas C. Hasenberg, David H. Chow
  • Patent number: 5577062
    Abstract: A semiconductor laser diode apparatus has a substrate of a first conduction type, a first clad layer of the first conduction type which is formed on the substrate, a current block layer which is formed on the first clad layer, a V groove stripe which is formed in a vertical direction so that a tip of the V groove can arrive at the first clad layer in depth, an active layer which is formed on the first clad layer and the current block layer along the V groove stripe without a low resistrance layer, a second clad layer of a second conduction type which is formed on the active layer, a contact layer of the second conduction type which is formed on the second clad layer, a first electrode which is formed on a surface of the substrate which is reverse side of a surface on which the first clad layer is formed and a second electrode which is formed on a surface of the contact layer. Therefore a low threshold current level can be achieved.
    Type: Grant
    Filed: December 21, 1994
    Date of Patent: November 19, 1996
    Assignee: Ricoh Company, Ltd.
    Inventor: Takashi Takahashi
  • Patent number: 5577144
    Abstract: A tubular body for use with an optical fiber connector, and the connector using such a tubular body. The optical fiber connector includes a coupling nut with an aperture formed therein, a spring and a retainer which are axially arranged on the tubular body. The coupling nut and the spring are retained externally on the tubular body by the retainer with the coupling nut being movable along the outside surface of the body and axially displaced by the spring. The body includes a retainer attachment portion on the outside surface thereof. The retainer attachment portion includes an annular groove and an annular ridge which are formed on the outside surface thereof. The annular groove is sized and dimensioned for receiving a radially applied retainer. The outside diameter of the attachment portion on the outside surface of the body is sized and dimensioned for receiving an axially attached retainer.
    Type: Grant
    Filed: May 30, 1995
    Date of Patent: November 19, 1996
    Assignee: The Whitaker Corporation
    Inventors: Michael D. Rossana, David D. Erdman