Abstract: Method and apparatus for varying the output signal frequency of a controlled oscillator. The oscillator control signal is formed by filtering the output of a random number generator in such a way that the oscillatory output signal has a random frequency walk phase characteristic having predetermined, controlled characteristics.

Abstract: A ring laser gyroscope includes a laser ring having at least three reflective surfaces. At least one of the reflective surfaces is partially reflecting and partially transmissive for removing a portion of the laser light within the ring, and for directing the removed light onto an output detector. Optical elements are provided for displacing the light directed on the output detector in a fashion by which a portion of the light from one of the counter rotating beams only partially overlaps the light from the other beam. A detector is provided for detecting the intensity of each of the counter rotating beams from the nonoverlapping beam portions on the detector and for detecting the fringe motion of the interfacing beams produced by the overlapping portions of the beams on the detector.

Abstract: A device usable as a tunable light filter or as a light valve having an electronically isolated element of a solid, insoluble material capable of reversibly changing state by reaction with soluble reactants. The state-changing element receives the reactants by diffusion through an electrolyte from a generator electrode.

Abstract: An electro-optic sensor for precise, direct and continuous measurement of the angular displacement between two bodies. A linear array of photodetectors is disposed on a planar surface mounted on the first body parallel to the axis about which the displacement is to be measured. The line of the array is perpendicular to this axis. A light source disposed on the planar surface near the photodetector array transmits light through optics to a reflecting reference flat mounted on the second body. The optics collimates the transmitted light and causes the reflected image of the light source to be spread into a line on and perpendicular to the photodetector array. This line image moves along the linear array as angular displacement occurs between the two bodies. No mechanical moving parts are required in the sensor.

Abstract: A new compound consisting essentially of strontium, iron, boron and oxygen is termed strontium ferrite borate or corabelleite. A fluxed melt for the growth of single crystals and a method for growing single crystals of the corabelleite are disclosed.

Abstract: A new compound consisting essentially of strontium, iron, boron and oxygen is termed strontium ferrite borate or corabelleite. A method for preparing polycrystalline ceramic corabelleite is disclosed.

Abstract: A method of producing a color change in a distinct element of solid, insoluble color changing material capable of reversibly changing color by reaction with soluble reactants. Reactants at a point spaced apart from the distinct element are electrochemically generated, diffuse through an electrolyte, and react with the distinct element to cause a reversible color change.

Abstract: A deposit of electrochromic display material such as, for example, lutetium diphthalocyanine chemically treated to have substantially the same color as electrolytically cycled deposits of the same display material.

Abstract: A display device is disclosed having a display matrix composed of electronically isolated display elements of a solid, insoluble display material which is capable of reversibly changing color by reaction with soluble reactants. The display matrix is driven by a drive matrix which electrochemically generates the soluble reactants which consist of oxidizing and reducing agents. A selective separator, which is permeable to electrolyte but impermeable to the generated soluble reactants, divides the interior of the device into two compartments; it confines the electrochemically generated soluble reactants and certain soluble chemical species to the compartment containing the generator electrodes and the display matrix and thereby prevents contamination of the other compartment having counter electrodes therein.

Abstract: A proof mass for an accelerometer is electromagnetically constrained in three orthogonal directions. An array of filaments forms an elastic suspension for the proof mass to constrain it in the remaining degrees of freedom. The resulting instrument has the potential for low cost and high-accuracy operation over a wide temperature range without the use of temperature controls.

Abstract: A proof mass for an accelerometer is electromagnetically constrained in three orthogonal directions. An array of filaments forms an elastic suspension for the proof mass to constrain it in the remaining degrees of freedom. The resulting instrument has the potential for low cost and high-accuracy operation over a wide temperature range without the use of temperature controls. The array of filaments becomes relatively compliant in all six degrees of freedom when loading exceeds a selected design load. This provides overload protection since the proof mass can be brought to a practical mechanical stop for support before excessive stress can fracture a filament.

Abstract: A proof mass for an accelerometer is electromagnetically constrained in three orthogonal directions. An array of filaments forms an elastic suspension for the proof mass to constrain it in the remaining degrees of freedom. The resulting instrument has the potential for low cost and high-accuracy operation over a wide temperature range without the use of temperature controls. In a preferred embodiment, forcing along the longitudinal axis of the proof mass is provided by a single helical coil disposed in a magnetic field directed radially relative the proof mass longitudinal axis. The polarity of the magnetic field is fixed around the periphery of the helical coil.

Abstract: A proof mass for an accelerometer is electromagnetically constrained in three orthogonal directions. An array of filaments forms an elastic suspension for the proof mass to constrain it in the remaining degrees of freedom. The resulting instrument has the potential for low cost and high-accuracy operation over a wide temperature range without the use of temperature controls. An improved transition device provides a relatively simple, controllable and inexpensive means for temperature stabilizing the elastic suspension.

Abstract: A proof mass for an accelerometer is electromagnetically constrained in three orthogonal directions. An array of filaments forms an elastic suspension for the proof mass to constrain it in the remaining degrees of freedom. The resulting instrument has the potential for low cost and high-accuracy operation over a wide temperature range without the use of temperature controls. Means are provided in the accelerometer for dynamically nulling the bias.

Abstract: An acoustic wave device wherein each electrode element of an interdigital transducer is buried or embedded between a pair of layers of piezoelectric material. The use of a multi-layer stack of layers of piezoelectric material enables each electrode element of the transducer to be sandwiched between a distinct pair of layers and thus to be insulated from the other electrode element or elements. Because of the insulation thus provided, the spacing between the fingers of each electrode element may be selected without fear of causing short circuits between electrode elements.

Abstract: A dithered ring laser gyro in which the effects of mode locking, or frequency locking, at low rotation rates are reduced by producing an oscillatory flow of the ionized gas in the gain section of the laser. The envelope in which the laser is sealed includes a pair of closed-end bellows. The bellows are extended and retracted in push-pull to pump the gas. There is thus created a dynamically varying pressure differential and oscillatory gas flow along the bore of the gain section of the laser which induces a corresponding oscillatory bias in the gyro output.

Abstract: Deposition of ordered polycrystalline films of zinc oxide and other materials having a strongly preferred crystal growth direction and a high degree of symmetry about the preferred direction is achieved consistently by disposing a charged electrode in a sputtering chamber to limit bombardment of the film and underlying substrate by charged particles.

Abstract: Single crystal magnetoplumbite is grown at temperatures under 1000.degree. C. from a fluxed melt having a selected concentration ratio of boron oxide to lead oxide and a selected concentration of iron oxide sufficient to cause magnetoplumbite to crystallize yet not so much iron oxide as will cause the melt's crystallization temperature to exceed 1000.degree. C.

Abstract: Single crystal 2PbO.Fe.sub.2 O.sub.3 is grown from a fluxed melt having a selected concentration ratio of boron oxide to lead oxide and a selected concentration of iron oxide sufficient to cause 2PbO.Fe.sub.2 O.sub.3 to crystallize yet not so much iron oxide as will cause other phases to crystallize.

Abstract: A two degree-of-freedom, free-rotor, gas-bearing gyroscope having greatly reduced sensitivity to acceleration-induced and other disturbances. An electromagnetic forcer acts on the rotor to keep the axial component of bearing deflection negligible. Closed-loop control circuitry for energizing the axial forcer responds to a linear displacement signal. The circuitry also provides an output signal proportional to the component of acceleration along the spin axis. This signal may be used to replace an accelerometer output signal in navigation equipment. In addition to be being functional during normal operation, the control functions during start-up and shut-down to center the rotor over the support ball. The functions of forcer and torquer are combined in a single structure. A dual motor arrangement and a dual forcer-torquer arrangement provide cancellation of bias variations due to housing, shaft, and bearing deflections.