Abstract: An electrooptic device for controlling the intensity of a monochromatic light beam comprises a first transparent element such as a triangular prism or hemicylindrical prism having a planar surface. A thin layer of a material such as a metal is in contact with the planar surface of the transparent element and a semiconductor material is adjacent to the metal layer. A voltage source provides a potential difference between the metal layer and the semiconductor material to alter the charge density in the semiconductor material to affect the degree of coupling between the light beam entering the device and surface plasmon waves generated within the device to correspondingly control the intensity of the light beam exiting the device.

Abstract: A wideband switch crosspoint and crosspoint matrix can be provided in which direct current through a multiplex switching means enables additional circuitry and extends attenuation between the "on" and the "off" states of the switching means.

Abstract: United States paper currency can be denomination sensed by a system for scanning a predetermined path along one surface and comparing the resultant scan against a standard for a particular denomination. Subsequently, it is determined whether the scanned currency is of a particular denomination or is questionable. The one surface can be an obverse surface of paper currency, the predetermined path of the obverse surface can be magnetically scanned; the scanning direction occurs along a major axis of the currency; and the scanned currency can be sorted in accordance with the determination. Various denominations can be determined at one time either in seriatim or in parallel.

Abstract: An electrooptic device for controlling the intensity of a monochromatic light beam comprises a transparent element having opposed planar surfaces operable to reflect a collimated light beam alternately from the two surfaces. A plurality of semiconductor structures contact one surface of the device at regions where the collimated light beam reflects from that surface. Each semiconductor structure includes a thin layer of a material such as a metal in contact with the planar surface of the transparent element and a semiconductor material adjacent to the metal layer. A voltage source provides a potential between the metal layer and the semiconductor material of each structure to separately alter the charge density in the semiconductor material of each structure to affect the degree of coupling between the light beam entering the device and surface plasmon waves generated within each structure. The device is operable as a signal mixer or an optical logic switching device.

Abstract: A dichroic beamsplitter includes two glass prisms, each having an isosceles right triangular cross section, with a multilayer dielectric coating sandwiched therebetween. Each layer of the coating is tuned for quarter-wave operation with 45.degree. incidence of light at 0.83 .mu.m. The coating comprises 53 layers of three different materials arranged in a specific order. The materials have refractive indexes of 1.45, 1.625, and 2.25 and can be, for example, silicon dioxide, aluminum oxide, and titanium oxide. An optical fiber transmission system includes an optical fiber and a beamsplitter at opposite ends thereof. One of the beamsplitters is oriented with respect to the fiber at 43.degree. incidence and has a high nonpolarizing reflectance at a wavelength .lambda..sub.2 and a low loss transmission at a wavelength .lambda..sub.1. The other beamsplitter is oriented with respect to the fiber at a 47.degree. incidence and has a high nonpolarizing reflectance at the wavelength .lambda..sub.

Abstract: A high voltage cable/connector assembly of an improved design for substantially minimizing or eliminating damaging corona and voltage arc-over effects. The assembly in accordance with the invention includes a high voltage cable having a cable shield (e.g., a braided shield), a high voltage metal connector secured to and surrounding a portion of the cable and in physical and electrical contact with the cable shield, and a metal horn-shaped corona shield connected in series with the metal connector and defining a cavity through which a portion of the cable, including a center conductor and a surrounding bare plastic dielectric, passes longitudinally. The corona shield serves to eliminate sharp edges or abrupt terminations in the vicinity of the cable shield, metal connector and corona shield so that corona discharge is effectively prevented.

Abstract: A telecentric optical fiber connector, wherein light from an optical fiber is emitted from the connector lens in a comparatively large diameter parallel beam, includes two primary components: an integral optical quality plastic connector body having an annular planar reference surface substantially perpendicular to an optical axis. A convex lens surface is molded, recessed inward from the reference surface. The body is substantially cylindrical, with exterior means thereabout so that it can be engaged with a similar body. The opposite axial end of the body has a central cylindrical cavity therein which extends to a point which is one focal length from the lens surface. A fiber holder, which holds an optical fiber centrally within an axial hole, abuts an end of the fiber against the point one focal length from the lens surface, and can be engaged with index-matching material.

Abstract: A forward error correcting apparatus employing the Kasami algorithm for trapping errors in a half-rate Golay codeword. The Golay code is defined as an (n, k, t) or (23, 12, 3) polynomial code in which each codeword is n=23 bits long, contains k=12 data bits and (n-k)=11 redundant check bits, and corrects up to a maximum of t=3 errors.The forward error correcting apparatus includes an input data register circuit arranged to receive, store and shift therealong the data bits of the Golay codeword, and a Golay shift register circuit arranged to receive, store, shift and recirculate therein the data and check bits of the Golay codeword. The codeword shifted and recirculated within the Golay shift register circuit is divided by a generator polynomial g(x) expressed by x.sup.11 +x.sup.10 +x.sup.6 +x.sup.5 +x.sup.4 +x.sup.2 +1 to derive a syndrome word which is examined in a Kasami error trap circuit in accordance with the Kasami algorithm to detect one of three possible error situations.

Abstract: A digital data correlator is provided which detects the presence of a particular sequence, or correlating pattern, of binary data bits in a serial binary data stream, is tolerant of data errors, and is adjustable to accept different numbers of data errors. The correlator includes a shift register of the CMOS type, a plurality of inverters of the CMOS type connected to selected outputs of the register at which bits of a particular logic value are expected for a properly positioned correlating pattern in the register, and a plurality of like-valued resistances coupled to the outputs of the register and to the inverters. Erroneous bits in the register cause an error voltage to be produced at a common node point coupled to the resistances. The value of the error voltage is compared in a comparator against a threshold reference voltage of a value related to an acceptable number of erroneous bits.

Abstract: Switchboard apparatus includes means for supporting a bus bar including an elongated steel member having at least one bolt hole therethrough, the steel member being coated with an insulative material. A pair of formed washers of protective material are adapted to seat within the hole at opposite sides of the steel member. A member bolt fits within the washers and the hole, and a nut is adapted to engage with the bolt with a flat washer fitting between the bolt and one of the formed washers.

Abstract: A comparator circuit of one type, prior to this invention, had a reliability problem due to an undesirable conductive path, and had limited speed due to stray capacitances. Reliability is achieved through separate triodes for coupling an inverted storage pulse to a primary electrode of each of two triodes of a differential amplifier. Speed is achieved through coupling a transistor across the other primary electrodes of the differential amplifier, the transistor's gate electrode receiving a narrow pulse upon termination of the storage pulse.

Abstract: An optical fiber drawing furnace includes a graphite element of generally cylindrical shape with a reduced central cross-sectional configuration having a flange at opposite ends thereof and having an axial hole therethrough including a central internal element chamber for receiving a glass preform, means for water cooling the flanges, and means for applying electric power across the flanges to resistively heat the reduced cross-sectional configuration and, hence, the central internal element chamber so that an optical fiber can be drawn from the preform. The invention relates to prolonging the useful life of the graphite element by suitable methods and apparatus. The water used for cooling the flanges can be regulated to a temperature such as to avoid condensation of atmospheric moisture within the room (in which the furnace is located) upon the furnace. The application of electric power across the flanges can be increased and decreased at a gradual rate so as to avoid thermal shock to the graphite element.

Abstract: An arc chamber channel for providing cooling of an electric arc and quenching thereof for use with a circuit breaker includes an integral, generally U-shaped member which forms a base and opposing side walls. One end of the opposing side walls has extending tabs which are folded outwardly, providing a pair of point contacts for engaging side walls of a circuit breaker housing. An opposite end of the base is formed with an extending tab for engaging a molded feature of a side wall of the circuit breaker housing. Thus, all the extending tabs are adapted to space the channel away from the side walls of the circuit breaker, thereby exposing outer surfaces of the channel when in use in a circuit breaker. The base has an arrangement of venting holes therein. The tabs can be diagonally folded outwardly, and the channel can be formed of steel. An improved circuit breaker housing can include the channel, the housing further including a vent passage within the housing which is exterior to the channel.

Abstract: A furnace for drawing optical fiber includes a graphite element of generally cylindrical shape with a reduced central cross-sectional configuration having a flange at opposite ends thereof and having an axial hole therethrough including a central internal element chamber for receiving a glass preform, means for heating the reduced central cross-sectional configuration, and, hence, the central internal element chamber, so that an optical fiber can be drawn from the preform. The invention relates to providing a relationship between the internal diameter of the central internal element chamber and the inner diameter of the exhaust tubes so as to minimize gas turbulence within the central internal element chamber and thereby control the diameter of an optical fiber being drawn. The relationships can be such that the internal diameter of the central internal element chamber and the inner diameters of an input exhaust tube and an exit exhaust tube are substantially equal.

Abstract: An improved circuit breaker utilizing the combination of a pair of composition sheets and a channel. The sheets reside alongside opposing interior surfaces of a molded insulated housing and are held in place within recesses formed therein. The sheets are formed of material comprising a water-insoluble binder and an arc-suppressing substances selected from the class consisting of the oxides and hydrates of aluminum and magnesium, the binder constituting at least ten percent of the composition. The channel comprises an integral, generally U-shaped member forming a base and opposing side walls. One end of the side walls has extending widths to provide enlarged surfaces for engaging the composition sheets. Both ends of the base are formed with a tab for engaging a molded feature within the circuit breaker housing. The tabs and the composition sheets space the channel away from the interior surfaces of the housing, thereby exposing surfaces of the channel not in contact with the sheets. The base has venting holes.

Abstract: A centering device, for holding an optical fiber along an axis, includes three sections of fiber receiving means, and a receiving member. The receiving member has a cylindrical recess, concentric with the axis, for holding the sections in assembly. The sections are substantially identical, each having a uniform cross-sectional configuration at right angles along a major portion of its length forming a boundary of fixed perimeter. One portion of the boundary of one section contacts another section. Another portion of the boundary contacts a different section. A third portion contiguous to the first two portions is adapted to engage an optical fiber along its length. A fourth portion contiguous to the first two, but not to the third, engages the cylindrical wall defined by the concentric recess of the receiving member. The recess terminates with a planar wall perpendicular to the axis. It can have an axially oriented depression.

Abstract: Fast-response electronic surge arrestors for protecting electrical equipment from the damaging effects of large amplitude, fast rise-time voltage transients. An electronic surge arrestor in accordance with the invention includes first and second transient suppression circuits arranged in parallel and coupled between a flat elongated microwave strip transmission line conductor and ground potential for dissipating transients of first and second polarities appearing on the conductor. Each of the first and second transient suppression circuits includes a fast-response Zener diode and a switching diode arranged in a serial, oppositely-poled fashion and having biased junctions for dissipating transients of the first and second polarity, respectively, while minimizing dissipation of signals in the UHF band which may be received or generated by the electrical equipment and also appear on the microwave strip conductor.

Abstract: A movable contact is adapted to engage with and disengage from a fixed contact within a circuit breaker housing. A contact arm, coupled to the movable contact, is caused to trip when appropriate means are actuated. The invention resides in apparatus for actuating such means including a ferromagnetic material armature latch partially rotatable about a housing axis. The latch has a first retaining means and a first coupling surface. A latch member, partially rotatable about a housing axis, has a second retaining means and a second coupling surface adapted to couple with the first coupling surface. Further, the latch member is adapted to recouple the second coupling surface subsequent to it becoming uncoupled from the first coupling surface. A spring couples the two retaining means.

Abstract: Closed loop fiber optic link means, transferring energy from a radiant source to a receiver, includes serially connected fiber optic links and detectors. Energy cessation causes alarm. Detectors include: (1) A pair of optical transducers oriented whereby light, air transmitted, is received with insignificant loss. In water, light received is so insignificant that energy to the receiver ceases. The first transducer provides a light beam within a constant index of refraction medium to the second transducer spaced and oriented to ordinarily receive the light beam. When light passes through media having different refraction indices at non-normal angles, light is refracted whereby receiver energy ceases. The transducers are oriented in a straight inclined path. (2) Optical fiber, stable to approximately 135.degree. F., which melts above approximately 155.degree. F., provides fire detection. (3) A bimetallic element attached to one of axially aligned optical fiber holders, when heated, mis-align the fibers.

Abstract: A laser medium includes an ordered perovskite crystal of the general formula: A.sub.2 B Cr.sub.y B'.sub.1-y X.sub.6. A and B are alkali metal ions with the ionic radius of A greater than B. B' is an ion selected from the group consisting of Y.sup.3+, La.sup.3+, Gd.sup.3+, Lu.sup.3+, Sc.sup.3+, Al.sup.3+, Ga.sup.3+, and In.sup.3+. X is an ion selected from the group consisting of F.sup.-, Cl.sup.-, and Br.sup.-. A can be an ion selected from the group consisting of K.sup.+, Na.sup.+,Cs.sup.+, and Rb.sup.+. B can be an ion selected from the group consisting of K.sup.+-, Na.sup.+, and Li.sup.+. The chromium can be represented by Cr.sup.+3 ions. The laser media can be ordered perovskite polycrystalline compounds of the formulae: CsNaCr.sub.0.01 Y.sub.0.99 Cl.sub.6 ; KLi Cr.sub.y Sc.sub.1-y F.sub.6 (where y equals 0.01 and 0.10); K.sub.2 NaCr.sub.y Sc.sub.1-y F.sub.6 (where 0.01 .ltoreq.y.ltoreq.0.40).