Abstract:
The present invention relates to a method and apparatus for stabilizing a tremolo system in a string instrument, the tremolo system having a block and a number of tensioners in extension from the block. One aspect of the invention includes an apparatus, mountable to the string instrument, and having a first retainer to engage a first one of the tensioners and a second retainer to engage a second one of the tensioners, wherein the first retainer is closer to the block than is the second retainer when the apparatus is mounted to the string instrument.
Abstract:
An optical apparatus includes an optical fiber (13). A plurality of individual optical fiber deformation structures, comprising e.g. acoustic wave propagation members (18) and acoustic wave generators (24), are positioned adjacent along a length of the optical fiber. Each of an individual optical fiber deformation structure introduces a mechanical or index deformation of a portion of the optical fiber (36) (e.g. by a flexural acoustic wave) to create perturbations in the optical modes in the fiber and provide a coherent coupling between two modes in the optical fiber. This apparatus provides a wavelength tunable bandpass filter (e.g. acousto-optic tunable filter, AOTF) and can be used to recover the gain flatness of erbiumdoped fiber amplifiers (EDFA) or as add/drop filter.
Abstract:
An optical add/drop multiplexer includes a mode converter. A first mode coupler is coupled to an input of the mode converter. A second mode coupler is coupled to an output of the mode converter. The mode converter includes an optical fiber with multiple cladding modes and a single core mode guided along a core. An acoustic wave propagation member is coupled to the optical fiber. The acoustic wave propagation member propagates an acoustic wave from its proximal to its distal end. At least one acoustic wave generator is coupled to the proximal end of the acoustic wave propagation member.
Abstract:
A single helix chiral fiber grating of a predetermined grating strength is provided that is operable to control light transmission in a predetermined wavelength range. The novel fiber grating comprises a first optical fiber with a first interface portion at a first end, a second interface portion at a second end, and a middle portion therebetween. The first optica! fiber is configured with at least one fiber core, surrounded by a corresponding at least one cladding, with a first longitudinal section disposed within the first interface portion, a second longitudinal section disposed within the second interface portion, and also includes a longitudinal helical section, disposed therebetween within the middle portion, that comprises a longitudinal helix structure of a single predetermined handedness, having a predetermined pitch profile, and having a predetermined helix diameter profile selected and configured to produce the predetermined grating strength. The helical section of the novel fiber grating is preferably produced by placing the first optical fiber, proximal to and parallel with a second fiber (or equivalent elongated member), and longitudinally twisting them together to form a double helix structure. Advantageously, the diameter of the second fiber (or a diameter profile thereof) may be selected to achieve the predetermined helix diameter profile in the helical section of the first fiber. The second fiber may be left proximal to the first fiber after fabrication or removed.
Abstract:
The invention concerns a dynamically tunable optical filter comprising an index network (5) inscribed in a wave guide portion (1) comprising a core enclosed in an optical sheath. The invention is characterized in that the guide portion comprising the network (5) has at least one phase jump (8) dynamically inserted transversely.
Abstract:
An optical communication assembly includes a demultiplexer coupled to an input fiber, a multiplexer coupled to an output fiber and a plurality of optical fibers. Each optical fiber is coupled to one or both of the demultiplexer and multiplexer. A plurality of attenuators are each coupled to an optical fiber in the plurality of optical fibers.
Abstract:
An acousto-optic filter includes an optical fiber with a longitudinal axis, a core and a cladding in a surrounding relationship to the core. The optical fiber has multiple cladding modes. At least one acoustic wave generator is included and made of a sufficiently high frequency piezoelectric material to produce a longitudinal acoustic wave. An acoustic wave propagation member has proximal and distal ends. The distal end is coupled to the optical fiber and the proximal end is coupled to the acoustic wave generator. The acoustic wave propagation member propagates the longitudinal acoustic wave from the proximal to the distal ends and excites the longitudinal acoustic wave in the optical fiber.
Abstract:
An acousto-optic filter includes an optical fiber with a first region and a second region. A first acoustic wave generator is coupled to optical fiber. The first acoustic wave generator produces a first acoustic wave that travels in a first direction in the first region. A backward-propagating wave is generated in response to propagation of the first acoustic wave along the optical fiber. The backward-propagating wave travels in an opposite direction relative to the first acoustic wave. A first acoustic wave propagation member is coupled to the optical fiber. A second acoustic wave generator is coupled to the optical fiber at the second region. The second acoustic wave generator produces a second acoustic wave that combines with the backward propagating acoustic wave.
Abstract:
This invention relates to optical devices such as a fiber-optic frequency shifter and an optical interferometer. This invention also relates to a method of generating optical interference signals to obtain reliable sensor signals independent of polarization fluctuations of the optical waves in the fiber. Fiber-optic interferometers have many advantages such as high sensitivity and convenient way of using even in poor surrounding environments. These interferometer, however, exhibit polarization dependent signal degradation since the polarization of a light wave passing through an optical fiber irregularly changes depending on the birefringence of the fiber. This invention is characterized in that the frequencies of two orthogonal eigen polarizations of a light wave are shifted to different frequency values at one optical path of the interferometer. They produce two beat interference signals after interfering with the light wave passed through the other optical paht of the interferometer. The two beat interference signals have amplitudes varying complementarily. Selecting the larger one from the two beat signals can prevent polarization dependent signal degradation. Moreover, the beat signals from the optical interferometer according to the invention requires simpler signal processing compared to the output of conventional fiber-optic interferometer.
Abstract:
Procédé de fabrication d'un dispositif lumineux 100 comprenant les étapes de: a/ tissage d'un tissu 1 comprenant: des fils de chaîne4 et de trame 3 constituant l'âme du tissu 1; des fibres optiques 5 tissées en trame ou en chaîneau sein dudit tissu 1; lesdites fibres optiques 5 étant formées par un cœur et une gaine enveloppant ledit cœur; des fils de liage 2 formant partie des fils de chaîne4ou de trame, assurant le maintien desdites fibres optiques 5 au sein du tissu 1; b/traitement de surface du tissu 1 comportant les fils de liage 2 pour former des modifications de surface8 à la surface desdites fibres 5; c/retrait totaldesdites fibres optiques 5 du textile 1 traité; d/insertion d'une partie desdites fibres 5 rassemblées en un faisceau dans une enveloppe translucide 9.