Abstract: A space integrating optical ambiguity processor in which two one-dimensional modulators provide two-dimensional processing capability. Signals to be processed drive orthogonal Bragg cells oriented 40.degree. to the axes of the output detector. The resulting product is transformed in one dimension and imaged in the other, thereby creating a light intensity distribution representative of the cross ambiguity between the input signals.

Abstract: An apparatus for controllable propagation of magnetic domains, or bubbles, through an arrangement of closely spaced magnetic propagating elements arranged in an input stage, a strip-former stage, and a decoder stage. Binary logic circuitry results from selective control of bubble movement through alternate paths of elements, with at least one of said paths producing a domain strip extending the full height of the strip-former stage. The decoder stage includes a propagating element spaced apart from the strip-former stage a distance sufficient to prevent propagation of all domains in the strip-former stage except for the full-height strip.

Abstract: An apparatus for simultaneously generating identical cipher key at two remote terminals in a manner which prohibits interception of the key by unauthorized persons. A circuit comprising three separate wire lines is connected between the two terminals over geographically separated routes. The circuit is randomly completed and broken by a switch at each terminal, the switch position being determined at each terminal by an independent key generator. Cipher key is communicated by comparing the key generator output and the circuit condition.

Abstract: An optical fiber having a parabolic-index profile is etched to a taper below the cladding layer. A prism contacts the taper along its length within the etched portion of the fiber, and coherent light is transmitted through the prism into the fiber. Selective control of the light beam entry angle, entry position along the taper, and control of the etching depth allows excitation of specific modes within the fiber and maximization of coupling efficiency.

Abstract: An improved method and apparatus for laser recording of information onto a metal film by dynamically heating the film immediately prior to recording. A single track of information is recorded by directing two laser beams onto the film. An unmodulated preheat beam supplies energy to raise the temperature of the metal film to just below that required for recording. A modulated write beam then provides sufficient additional energy to selectively raise the temperature of the film to a necessary level for recording of data.

Abstract: A precision linear tuning circuit having particular utility to applications employing superconductors in a supercooled environment. Two capacitors, one fixed and one variable, are connected in parallel by an arrangement of shared, concentric electrodes. The variable capacitor includes one electrode and a movable facing dielectric which are tapered such that displacement of the dielectric results in a linear variation in tuning frequency.

Abstract: An apparatus for altering frequencies such that any one of a plurality of input frequencies automatically becomes another specified frequency. The value of the output frequency will remain constant regardless of which input frequency chosen, as long as the input frequencies have the relationship a, 2a, 4a, 8a . . . An input signal is received by a descending cascade of units composed of multipliers and filters. The multiplier portion of each unit must be in series with and receive the input stimuli before the filter portion of each unit. Each multiplier portion of the unit must also have a control input of a predetermined value. A phase lock loop inside of a feedback loop compensates for instantaneous variations of frequency in the input signal. This feedback loop is connected from the multiplier-filter unit to the control input for each multiplier portion.

Abstract: A method of position fixing an active transmitter source. At least two passive receivers are utilized to position fix at least one active transmitter source by obtaining the difference of the doppler frequencies received at the passive receivers, the receivers being tuned to the transmitter frequency. This differential doppler frequency is processed together with navigational information relative to the passive receiver positions at selected measurement intervals along a given measurement path of receiver movement, in order to fix the unknown position of the active transmitter source.

Abstract: A digital bridge for a telephone conferencing circuit which provides multiple conferencing capability. Microprocessor signals to a buffered memory control switching of parallel communications data into a time division multiplexed serial stream for transmission, with the position of data within each frame of the stream being a function of the intended destination. High speed switching capability results from the buffered memory circuit which is simultaneously filled with new data as current data is utilized.

Abstract: An coherent light optical system is described wherein a high frequency electrical signal modulates an optical signal. An electronic lens, whose optical properties may be easily controlled, results from control of the modulating signal. The principles of feedback are utilized for optical aberration detection and correction of the lens.

Abstract: A variable integrated optical logic element, formed on a substrate of electro-optic material, capable of being controlled to perform the six basic logic operations AND, OR, EXCLUSIVE OR, NAND, NOR and EXCLUSIVE NOR. The optical logic element comprises a plurality of single-mode optical waveguides which form a group of parallel and series equal-arm interferometers. The optical logic element operates on the principle of constructive and destructive interference between light beams. Voltage means are provided for varying the index of refraction of certain of the optical waveguides, to produce relative phase differences in the light energy propagating therein. By inducing phase shifts in the light energy propagating in appropriate waveguides, each of the six basic logic operations can be performed. Also disclosed is an electrically passive, phase-sensitive optical coupler, which is used for switching light energy between waveguides.

Abstract: Disclosed are acousto-optical information processors employing a two-dimensional, time-integrating architecture. These three-product type processors are multi-purpose processors which can perform a variety of complex signal processing operations in two-dimensions, without requiring two-dimensional spatial light modulators. Typical of these processing operations are two-dimensional correlation, spectrum analysis, and cross ambiquity function processing. Some of the two-dimensional processing operations are made possible by the incorporation into a two-dimensional correlator of a distributed local oscillator, which may be implemented with mechanical-optical or electro-optical techniques. The acousto-optical processors may be easily implemented with readily available optical and acousto-optical components.

Abstract: A process for the production of a phase hologram of tanned gelatin in a gtin matrix from silver halide photographic material is disclosed in which the silver halide photographic material is exposed, developed with a non-tanning developer, bleached with a tanning bleach which removes the metallic silver of the metallic silver image areas while tanning the gelatin in the metallic silver image areas, and is fixed with a non-tanning fixing agent to remove the silver halide from the photographic material.

Abstract: An automatic astroposition determination apparatus for performing measurets with improved precision and accuracy. A rectangular photosensor array is mounted in the focal plane of a theodolite and as the image of a star moves across the sensor array, a display of the image position and the time elapsed since the commencement of tracking is provided. Circuitry is provided to ensure that the leading edge of the star image on the array is tracked irrespective of how many photosensor elements the image overlies and irrespective of the direction of image transit on the array.

Abstract: A gasket structure for the door frame of an electromagnetically shielded enclosure having a flexible inflatable tube with a sleeve or coating of conducting material which upon inflation with the door closed provides intimate electrical contact between the door and the door frame.

Abstract: An improved apparatus is disclosed for adjustably mounting an aerial photaphy camera externally of an aircraft, including a support adapted for attachment to the outside of an aircraft, an aerial photography camera, a control rod connected at one end with the camera, and a bearing device connecting the control rod with the support, said bearing device affording both rotation of the control rod about its longitudinal axis, and pivotal movement of the control rod about a generally horizontal pivot axis, whereby when the support is connected with the airplane, the camera may be adjusted to an orientation in which its optical axis extends vertically.

Abstract: A work holder used for guiding a workpiece moved from one position to another during placement of the same and particularly sheet piling. The holder has an elongate rigid arm with an abutment at one end thereof for bearing against a rigid structure and a friction reducing unit at the other end of the arm for bearing against the workpiece during movement of the same. Between the abutment and the friction reducing unit there is a device for applying pressure to the arm to press the friction reducing unit against the workpiece. The pressure applying device has a first unit adapted to be detachably anchored to the rigid structure and a second unit, variable in length, connecting the first unit to the arm.

Abstract: A bracket is disclosed for attaching an oxidation test fixture or the like to a pair of parallel boiler tubes. The bracket includes a support bar, a pair of jaws the remote faces of which each has a configuration which conforms generally with the adjacent portion of the outer periphery of the associated boiler tube, and shaft means with oppositely threaded ends connecting the pair of jaws. The bracket is placed between the boiler tubes and the threaded shaft is turned to simultaneously displace the jaws apart into tight engagement with the tubes. A test rack designed to hold various metal samples is then attached to the support bar.

Abstract: Apparatus for direct current to alternating current power conversion by means of progressive variation of magnetic flux in associated magnetic paths. A direct current input is subdivided into power pulses in two permeance controlled transformers. The pulses are modified, stabilized and recombined in phase opposition to produce a single alternating current output.