Abstract: A light source (10) coupled to a first fiber optic waveguide (14) which is coupled by a first directional coupler (22) and a second directional coupler (24) to a second waveguide (20). The first waveguide (14) has a phase modulator (60), a delay loop (62) and a polarization controller (68) therein to cause a differential delay time T on counterpropagating coherent light waves phase modulated at a frequency 1.sub.M. The first directional coupler (22) has one part connected to a photodector (28) and the second directional coupler (24) has a probe (20D) coupled to the first fiber (14) and the second fiber (20). The probe directs light toward a surface (18) whereupon the counterpropagating waves are shifted in phase by an amount proportional to the amplitude of displacement of the surface 18.

Abstract: A fiber optic tapped delay line is disclosed which has a number of taps simultaneously fabricated in a single length of optical fiber. The light output from each tap is detected by either an electronic photodetector or by an output segment of optical fiber having a lapped surface, the latter technique also being utilizable in the mass production of optical couplers. The device may be used as a transversal filter by summing the outputs from the taps, and the frequency passband may be custom-tailored by selectively weighting the outputs from individual taps.

Abstract: A fiber optic data distributor utilizes a one-by-n single mode optical fiber directional coupler to distribute data from a single fiber to a plurality of separate fibers. The separate fibers may supply data from a central processing unit to peripheral units, which may also input data to the separate fibers for transmission to the central processing unit.

Abstract: The invention relates to a continuous method of removing tin from lead. The method comprises maintaining a pool of molten lead at a temperature of from 510.degree. C. to 570.degree. C., introducing molten lead into the pool, injecting chlorine and oxygen into the molten lead in an amount to react with tin present as an impurity in the lead to form a tin-containing dross and then separating the lead from the dross.Separation may either be performed in the reaction vessel itself or in a separate settlement vessel.

Abstract: A fiber optic recirculating memory is disclosed which utilizes dual couplers to form a splice-free recirculating memory device from a length of single mode optical fiber forming a loop which acts as a delay line and a second length of single mode optical fiber which provides an input end and an output end for the device. A single signal supplied as an input to the device will result in a series of output signals identical to the input signal, although at smaller, decreasing amplitudes; the invention prevents the first output signal from being substantially larger than the rest of the output signals, thus eliminating the need for protective circuitry on the output end or the rejection of the first output signal.

Abstract: An analog adaptive filter for deconvolving distorted signals. A clipped vion of the least mean square algorithm is implemented in a first embodiment by placing an acoustic surface wave storage correlator in a feedback loop and performing an iterative two step process to adjust the weight function of the correlator to make the output of the filter converge to a desired signal. In the first step, the distorted signal is applied to the top plate port of the storage correlator and the filter output from the acoustic port is delayed and subtracted from a training signal to produce an error signal. In the second step, the error signal is applied to the top plate port and the distorted signal is applied to the acoustic port which results in the correlation of the acoustic signal and the plate signal being added to the weight function stored in the storage correlator. The two step process is repeated until the filter output from the plate port converges to an approximation of the training signal.

Abstract: A continuous method and apparatus for removing copper from lead comprises introducing molten lead and sulphur to the upper end of a vertical stirred reaction vessel, maintaining a dispersion of sulphur in the lead without substantial back-mixing and thereafter recovering the dispersion and allowing the formed copper sulphide to float to the surface. The process is suitable for continuous operation on a small scale, e.g. 3 tons per hour, is environmentally acceptable and requires a lead inventory only about one third of that required by conventional batch processes.

Abstract: Hg.sub.1-x Cd.sub.x Te is an important semiconductor for use in photovoltaic and photoconductive infrared photon detectors. Hg.sub.1-x Cd.sub.x Te can be grown by liquid phase epitaxy at atmospheric pressure from a Te-rich solution in which case the Hg vapor pressure is below 0.1 atm at 500.degree. C. This low vapor pressure makes possible the use of open-tube, slider growth techniques. The present invention describes a covered graphite slider system which provides an additional source of Hg, minimizes loss of Hg from the source wafer and virtually prevents loss of Hg from the (Hg.sub.1-x Cd.sub.x).sub.1-y Te.sub.y growth solution.

Abstract: Hg.sub.1-x Cd.sub.x Te is an important semiconductor for use in photovoltaic and photoconductive infrared photon detectors. Hg.sub.1-x Cd.sub.x Te can be grown by liquid phase epitaxy at atmospheric pressure from a Te-rich solution in which case the Hg vapor pressure is below 0.1 atm at 500.degree. C. This low vapor pressure makes possible the use of open-tube, slider growth techniques. The present invention describes a covered graphite slider system which provides an additional source of Hg, minimizes loss of Hg from the source wafer and virtually prevents loss of Hg from the (Hg.sub.1-x Cd.sub.x).sub.1-y Te.sub.y growth solution.

Abstract: A mold for continuously casting molten metal, which mold has a friction-reducing material disposed so that the surfaces of the copper liner and the steel backing plate of the mold bear against this material instead of directly against each other. Specifically, the friction-reducing material must possess a coefficient of friction significantly less than the coefficient of friction which results when copper bears against steel. Consequently, the restraint against thermal expansion is minimized, resulting in less distortion of the liner.