Other

USA as Represented by Secretary of the Navy

University of California

Rockwell International Corporation

Amoco Corporation

Sang K Sheem

William K Burns

Henry F Taylor

Thomas G Giallorenzi

Shyh Wang

Bruce A Vojak

Susan K Sheem

The size and cost of fabricating fiber optic pressure sensors is reduced by fabricating the membrane of the sensor in a non-planar shape. The design of the sensors may be made in such a way that the non-planar membrane becomes a part of an air-tight cavity, so as to make the membrane resilient due to the air-cushion effect of the air-tight cavity. Such non-planar membranes are easier to make and attach.

Low-cost fiber optic pressure sensor

A novel means for interconnecting two optical components is disclosed, in which there are two connecting surfaces with matching surface features, and one optical component is located at a predetermined location on the first surface, and the other optical component is located at a matching location on the second surface. When the two surfaces are mated in a face-to-face fashion, they are locked into a stable position through the matched surface features. The first and the second optical components are aligned properly as they are located at a same spot with respect to the face-locking surface features. The unique surface features and the locations of the optical components may be registered by a lithographic method that has a sub-micron accuracy. Modular approach is feasible in which a combination of face-lock embodiments are stacked together to align a number of optical components. When the surface features has periodic patterns, more than one stable locking positions can be achieved, realizing optical switching capability.

Face-lock interconnection means for optical fibers and other optical

Novel embodiments and manufacturing methods for optical fiber connector plugs and sleeves are disclosed, in which precision holes are fabricated through a thin slab, preferably using preferential etching technique on a semiconductor wafer, such as silicon or gallium arsenide. The angle of the slope is specific in the preferentially etched through-holes. Optical fibers are inserted into the V-shaped through-holes, with the orientation perpendicular to the surface of the slab. The edges of the slab may be sloped at the same slope angle of the through-holes. The same technique can be used to fabricate a sleeve with a twin V-square recess with the same slope angle on the both ends. Since the slope angles are all same and specific, precisely-fitting through-holes, plugs, and sleeves may be fabricated for single-fiber connection and array connection.

Micromachined holes for optical fiber connection

An optical fiber interconnecting structure for connecting an optical fiber to an optical channel waveguide, in which a channel waveguide is extended collinearly by a hollow channel with sectional area and shape substantially identical to those for the channel waveguide. An optical fiber is laid collinearly with the channel, and a core-extension is formed at the end facet of the optical fiber to form a gradual and smooth optical transition to the channel waveguide. The channel waveguide may be tapered out to have a substantially larger sectional area at the far end so as to ease the optical interconnection.

Optical fiber interconnections using self-aligned core-extensions

The basic embodiment of the present invention comprises an optical fiber having cores and a claddings, and core-extensions, wherein the individual core-extensions are built onto the core end facets in a shape of the diverging horn-like structure, with the sectional area increasing gradually as the individual core-extensions extend farther away from the core end facets to merge together and form a common core-extension for light mixing and coupling. The core-extension may be made of a photo-reactive material to be shaped after the diverging radiation pattern of light emitted from the core end facets.

Optical fiber coupler with overlapping core-extensions, and

A laser which contains a substantially planar waveguide wherein the waveguide along the direction of light propagation is comprised of varying combinations of high-gain and low-gain regions so that the cumulative gain from one end of the optical cavity to the other varies as a function of position along a line within the plane of said waveguide which is perpendicular to the direction of light propagation.

Laser having a substantially planar waveguide

A dart game toy that is suitable for simulating the popular ball games comprises a dart, a group of offensive target pieces to be used by offensive team, and a group of defensive target pieces to be used by defensive team, wherein one game play consists of a set of sequential dart throwings being thrown alternately by offensive team and defensive team. The objective of the offensive team is to have the dart landed on the offensive target pieces, and the objective of the defensive team is to have the dart landed on the defensive target pieces that are recognized as defensive countermeasures against the offensive target pieces on which the dart have landed. Game rules are made in such a way that the outcome of the sequential dart throwings are interrelated and interlocked, making the result of the set of dart throwings determinable after and only after all the dart throwings belonging to the play have been completed. In the game, the ratio in sizes between each offensive target piece and the corresponding defensive target as well as the ratio among the targets of different play options reflect the level of difficulty of each play option.

Game toy

An optical fiber transmission path for interconnecting a transmitter and receiver for single mode operation at a predetermined wavelength. Most of the path is formed by a transmission cable made up of several optical fibers, spliced end-to-end, that are single mode at a wavelength longer than the predetermined wavelength, but possibly not single mode at the predetermined wavelength. The splice between the fibers is fabricated so as to exhibit minimized splice loss, as measured for only the fundamental mode at the predetermined wavelength. The transmission path of the invention also includes an optical fiber which is very short relative to the transmission cable and is in the path between the transmitter and the cable. The short fiber is selected to be single mode at the predetermined wavelength. A mode stripper is in the path, near the end of the transmission cable that is nearest the receiver. The mode stripper transmits only the fundamental mode at the predetermined wavelength.

Single mode operation with non-single mode optical fiber transmission

An optical fiber attenuator is fabricated using an adhesive liquid including submicron light absorbing particles. A portion at the end of a first optical fiber is coated with the liquid. The liquid is spread about the surface of the end of the fiber, as by ultrasonic vibration, to provide a uniform and very thin coat on the fiber. Then the first fiber is spliced at the coated end to an end of a second optical fiber.

Optical fiber attenuator and method of fabrication

A fiber optic interferometric physical sensor. A fiber optical Mach-Zehnder interferometer includes a sensor arm and a reference arm having different optical path lengths. A transducer coupled to the sensor arm modulates the phase of light signals passing therethrough in response to a physical quantity. The interferometer is supplied with an input optical signal which includes light components at two different wavelengths. The detected intensity of the output of the interferometer includes two components, each of which vary in relation to the physical quantity. Each output component is related to one of the two optical input wavelengths. The two output components differ in phase by an amount proportional to the path length difference between the sensor and reference arms and proportional to the wavelength difference between the light components of the input optical signal. The phase difference is adjusted such that the sensitivities of the two output components to the physical quantity are never simultaneously at a minimum. In an alternative embodiment, a single laser having a continuously variable wavelength is used with the interferometer having differing sensor and reference path lengths to achieve maximum sensitivity.

Fiber optic interferometer using two wavelengths or variable wavelength

A transmitter for fiber optics communication having a solid state light source device biased to emit light and a solid state optical amplifier device positioned adjacent the source device to receive the emitted light and amplify it. A modulation current is provided to one of the devices so as to cause a corresponding modulation of the output light from the optical amplifier, for transmission of the information contained in the modulation. The invention is advantageous for multiple state digital encoding. In addition, it can generate a multiplexed output, which facilitates demultiplexing of the information transmitted.

Optical transmitter with light source and optical amplifier combination

A multiwavelength multiplexer-demultiplexer constructed from units each cble of multiplexing or demultiplexing two wavelengths. As many such units as required can be interconnected to form multiplexer-demultiplexers of any number of wavelengths. Each two-wavelength multiplexer-demultiplexer unit includes a four-port power divider, a four-port phase shifter having two ports connected to two ports of the power divider, and another four-port power divider having two ports connected to two ports of the phase shifter. The power divider may be a single-mode optical fiber directional coupler, or a half-silvered mirror beam splitter. The phase shifter may include a pair of single mode optical fibers or a pair of oppositely disposed mirrors.

Wavelength multiplexer-demultiplexer

A Sagnac rotation-sensing interferometer with a fiber-optic loop for providing a closed optical path in which counter-propagating light beams are phase shifted due to the Sagnac effect and with an otical coupler for splitting an input beam into the counter-propagating light beams in the fiber-optic loop and for providing for interference between the output beams of the fiber-optic loop. The optical coupler includes a (3.times.3) coupler with two first output waveguides symmetrically disposed about an input waveguide for splitting the input beam into equal components and a (2.times.2) coupler with two second output waveguides adjacently disposed for providing interference between the output beams. The second output waveguides of the (2.times.2) coupler couple the first otput waveguides of the (3.times.3) coupler to the end of the fiber-optic loop.

Optical rotation-sensing interferometer with (3.times.3)-(2.times.2)

A Sagnac rotation sensing interferometer disposed on a rotating platform for use as a gyrsocope comprising a closed optical light path and a beam splitter for splitting an input light beam into two beams directed to transverse the closed optical path in opposite directions wherein the beam splitter is composed of a directional coupler with three input ports and three output ports. The first of the three input ports receives optical input and the second and third of the input ports are disposed symmetrically with respect to the first input port. Optical output from two output ports corresponding to the second and third input ports are directed to both ends of the closed optical fiber light path. A gyroscope according to this arrangement provides light output from the beam splitter which operates automatically near quadrature without a nonreciprocal .pi./2 phase bias applied in the fiber loop as required in conventional optical fiber gyroscopes.

Growing community of inventors

Richardson, TX, United States of America

Sang K Sheem