Abstract: A support is configured to support and apply a constant or near-constant tension onto a wire or string, such as a musical string of a stringed musical instrument. The wire is attached to a carrier that moves axially. One or more springs operate between the carrier and a point that is fixed relative to the carrier and apply a transverse spring force to the carrier. A spring angle is defined between a line normal to the axis and a line of action of each spring. The transverse spring force can have an axial force component and an axial spring rate that is a function of the spring angle. The carrier can be positioned so that the axial spring rate is zero, negative or positive. A primary spring can apply a primary force directed coaxial with the wire. If the wire changes in length the primary force will correspondingly change, as will the axial force component.

Abstract: A tensioner for a string on a stringed musical instrument is provided. The tensioner can include an elongated body, at least two spring modulation members, a spring modulation support, and at least one spring. Each of the spring modulation members have a first portion pivotably attached to a portion of the elongated body. The spring modulation support is pivotably attached to a second portion of each of the spring modulation members. The spring is interposed between the elongated body and the spring modulation support.

Abstract: A stringed musical instrument employs springs to apply tension to corresponding musical strings. Each spring is chosen and configured for its ability to impart a string tension generally matched to the appropriate tension of the string at perfect tune. Preferably, the spring is selected and arranged so that the tension in the string maintains at or near perfect tune even as the string elongates or contracts over time. In one embodiment, once a string is placed in appropriate tune, a mechanical visual indicator is set. As such, if tune of the string changes due to string elongation or contraction, the change is reflected by misalignment of the mechanical visual indicator even if the change cannot be aurally detected. Perfect tune can be reestablished by realigning the indicator. In another embodiment, a force modulating member is interposed between a spring and its corresponding musical string.

Abstract: A stringed musical instrument employs springs to apply tension to corresponding musical strings. Each spring is chosen and configured for its ability to impart a string tension generally matched to the appropriate tension of the string at perfect tune. Preferably, the spring is selected and arranged so that the tension in the string maintains at or near perfect tune even as the string elongates or contracts over time. In one embodiment, once a string is placed in appropriate tune, a mechanical visual indicator is set. As such, if tune of the string changes due to string elongation or contraction, the change is reflected by misalignment of the mechanical visual indicator even if the change cannot be aurally detected. Perfect tune can be reestablished by realigning the indicator. In another embodiment, a force modulating member is interposed between a spring and its corresponding musical string.

Abstract: A stringed musical instrument employs springs to apply tension to corresponding musical strings. Each spring is chosen and configured for its ability to impart a string tension generally matched to the appropriate tension of the string at perfect tune. Preferably, the spring is selected and arranged so that the tension in the string maintains at or near perfect tune even as the string elongates or contracts over time. In one embodiment, a force modulating member is interposed between a spring and its corresponding musical string. The force modulating member is adapted so that the tension actually applied to the string by the spring is not linearly related to the force exerted by the spring as the spring changes in length.

Abstract: A distributed packet switch to control data packet flows in a network is described. The distributed packet switch includes a means for operating over an asynchronous burst optical closed fiber medium. The distributed packet switch also includes at least one control system provided at a node to control data packet flow characteristics, such that the switch is configured to operate dependent on at least one efficiency parameter.

Abstract: A stringed musical instrument employs springs to apply tension to corresponding musical strings. Each spring is chosen and configured for its ability to impart a string tension generally matched to the appropriate tension of the string at perfect tune. Preferably, the spring is selected and arranged so that the tension in the string maintains at or near perfect tune even as the string elongates or contracts over time. In one embodiment, once a string is placed in appropriate tune, a mechanical visual indicator is set. As such, if tune of the string changes due to string elongation or contraction, the change is reflected by misalignment of the mechanical visual indicator even if the change cannot be aurally detected. Perfect tune can be reestablished by realigning the indicator. In another embodiment, a force modulating member is interposed between a spring and its corresponding musical string.

Abstract: A stringed musical instrument employs springs to apply tension to corresponding musical strings. Each spring is chosen and configured for its ability to impart a string tension generally matched to the appropriate tension of the string at perfect tune. Preferably, the spring is selected and arranged so that the tension in the string maintains at or near perfect tune even as the string elongates or contracts over time. In one embodiment, once a string is placed in appropriate tune, a mechanical visual indicator is set. As such, if tune of the string changes due to string elongation or contraction, the change is reflected by misalignment of the mechanical visual indicator even if the change cannot be aurally detected. Perfect tune can be reestablished by realigning the indicator. In another embodiment, a force modulating member is interposed between a spring and its corresponding musical string.

Abstract: A stringed musical instrument employs string tensioners to support and apply tension to corresponding musical strings. Each musical string is supported by one string tensioner, and each of the string tensioners is linearly movable independent of others of the string tensioners. Further, an adjustment mechanism is provided for selectively linearly moving each string tensioner. In a preferred embodiment, an effective playing length of each string is defined between the associated string tensioner and the nut of the instrument. As such, individual linear adjustment of the string tensioners enables the user to vary the playing length of the associated musical string. In other embodiments, a string tensioner is provided that supports a musical string from a position on a side of the string opposite the associated musical instrument surface.

Abstract: The invention provides an optical measurement system and method for monitoring the condition of a sail, the system comprising: an optical interrogation unit that produces and receives an optical signal; and an optical fibre network that interconnects the interrogation unit with a plurality of optical sensors in communication with the sail, wherein the sensors are mounted onto the sail. The optical system measures parameters of the sail, from which shape, integrity and overall conditions of the sail can be calculated in real-time.

Abstract: A stringed musical instrument employs springs and/or one or more hanging masses to apply tension to corresponding musical strings. Each spring and/or mass is chosen and configured for its ability to impart a string tension generally matched to the appropriate tension of the string at perfect tune. Preferably, the spring and/or mass is selected and arranged so that the tension in the string maintains at or near perfect tune even as the string elongates or contracts due to environmental factors or passage of time.

Abstract: This invention relates to a method and system to detect hysteresis/unstable regions of multi-section lasers. The method comprises the steps of obtaining a first set of measurement values for the output of the laser diode by increasing a first current through a range of values in a positive direction, increasing a second control current by a step, obtaining a second set of measurement values for the output of the laser diode by decreasing the first control current through a range of values in a negative direction, and increasing a second control current by a step. The process is repeated until a sufficient range of the second control currents has been used to provide resultant data which can then be processed in order to identify regions of hysteresis of the laser diode.

Abstract: The invention relates to a method and system for providing a set of continuous tuning regions from a discontinuously tuned laser, by providing a wavelength reference having at least first and second resonance peaks, sweeping the laser across a pre-determined wavelength range of the wavelength reference, and defining, within the laser sweep, one or more regions of continuous tuning operation of the laser, each of the regions corresponding to a response of the laser between adjacent resonance peaks of the wavelength reference. The advantage of the invention is that it provides a way for stitching together continuous regions of a multi-section tunable laser in an efficient and accurate manner.

Abstract: The invention provides a method and laser system for switching from a current operating point to a new operating point of the laser, the laser operating at a particular wavelength and includes a source channel and destination channel. The system switches and locks the output wavelength of a laser at ultra fast time scales (<50 ns) and compensate for degradation in the laser, and thermal transients in the device during the switching to ensure that within a certain time the laser has switched its wavelength to another wavelength within a specific accuracy and is not dependent on the previous wavelength of the laser.

Abstract: A system in which the controller (24) of a multi section diode laser such as a SG-DBR (10) is configured so that the laser can be swept rapidly in a pre-determined frequency direction through a series of frequency points by asserting a pre-calibrated series of sets of control input values to the sections of the diode laser, wherein the frequency points are obtained from cavity modes in a plurality of different supermodes, and the sets of control input values are pre-determined to take account of thermal transients that are known to arise from jumps in the output modes that occur when sweeping through the pre-calibrated series of sets of control input values in the pre-determined frequency direction.

Abstract: The invention provides a method to compensate for degradation in a tunable laser and ensure its performance by tracking the degradation and adjusting the control information accordingly. This is accomplished by performing some measurements of the output of the tunable laser at an initial setup or calibration procedure. Then, by effecting a periodic repetition of these measurements and using a comparison between these two measurements the present invention provides for a compensation factor for the operating conditions, primarily in the form of a look up table of operating points of the laser. These measurements show how much the operating points of the laser have drifted over the period since the last set of measurements, which provide control informatIon to compensate for degradation in the laser.

Abstract: A distributed packet switch to control data packet flows in a network is described. The distributed packet switch includes a means for operating over an asynchronous burst optical closed fiber medium. The distributed packet switch also includes at least one control system provided at a node to control data packet flow characteristics, such that the switch is configured to operate dependent on at least one efficiency parameter.

Abstract: A method relating to the calibration of tuneable lasers is described. The method provides for the provision of correct control currents so as to achieve each of desired output frequencies from the laser. The correct currents are determined by forming a matrix of the output characteristics of the laser at specific tuning currents and processing that matrix to determine stable operating points within the matrix.

Abstract: The invention relates to a method and network for providing an optical fibre wavelength routed network comprising a plurality of nodes on a network ring where each node can drop and add a wavelength, control means to control the wavelength to be transmitted on the network ring, and access means for each node to enable a node to transmit wavelength onto the network ring whereby wavelength collisions with transmit wavelength from other nodes are avoided in the network. The invention describes a network and method having a ring system with a plurality of nodes and an interconnection means to allow information to be communicated between the nodes of the network using packets of data on a wavelength in a novel and efficient manner.

Abstract: The invention relates to a method and system for providing a set of continuous tuning regions from a discontinuously tuned laser, by providing a wavelength reference having at least first and second resonance peaks, sweeping the laser across a pre-determined wavelength range of the wavelength reference, and defining, within the laser sweep, one or more regions of continuous tuning operation of the laser, each of the regions corresponding to a response of the laser between adjacent resonance peaks of the wavelength reference. The advantage of the invention is that it provides a way for stitching together continuous regions of a multi-section tunable laser in an efficient and accurate manner.