1358354 Automatic fault indication VEREINIGTE FLUGTECHNISCHE WERKEFOKKER GmbH 30 May 1972 [29 May 1971] 25318/72 Heading H2K [Also in Divisions F4 and H1] In fault-detecting equipment having pilot lamps which light up and/or flash when a fault occurs, each pilot lamp includes a light-emitting semi-conductor diode arranged behind a light diffusing screen. A switch 10 has a printedcircuit board 14 with three gallium arsenide diodes, a coloured filter 16 and a diffusing plate 17. Alternatively a single diode may be mounted on a printed circuit 141. A fault detecting circuit uses luminous constructions 23 which comprise three lightemitting diodes 15 forming a pilot lamp 20, a transistor 22 whose base is connected to a fixed potentiometer formed by Zener diode 26 and a resistance 27 and resistances 24, 25 which control the intensity of light from the diodes by coupled switches 75, 76. When a fault occurs, relay 28, preferably a reed switch, switches the diodes 15 on in pilot lamp 20 and the fault signal is also fed through resistance 60 and diode 61 to a switching stage 50 and a delay unit 40. After a delay, relay 35 is closed and the multivibrator 30 activated thus flashing the main warning lamp 21. The main warning lamp 21 does not flash if the fault lasts only a short time. When the signal of the main warning lamp 21 has been recognized it may be switched off by closing switch 70 or 71. This activates the thyristor 63 thus blocking the fault signal coming through resistance 60. (For Figures see next page.)

1,088,940. Electrostatic motors. ROSEMOUNT ENGINEERING CO. Nov. 25, 1964 [Nov. 26, 1963], No. 47994/64. Heading H2A. [Also in Division G1] In a transducer, a tube of non-circular crosssection is supported at one or more positions which constitute nodal points when the tube is vibrated at its natural frequency, the tube being adapted to be subjected to a differential pressure. The transducer may be used for the measurement of pressure or temperature, or as a frequency standard. As shown, Fig. 1, a flattened tube 10 with closed ends is vibrated in a transverse mode at its natural frequency by an electrical drive circuit comprising two plates 41, 44, equidistantly disposed between the flat surfaces of the tube near one end thereof, and a feedback amplifier 55. A test pressure is applied to the interior of the tube via a capillary tube at 29; this pressure determines the natural frequency of vibration, and a signal from terminals 36, 58 is fed to a frequencymeasuring device (not shown) to give an indication of the pressure. Tube 10 is supported by the capillary tube and by tensioned wires at nodal points on lines 12, 13 for vibration at the fundamental frequency; if a harmonic of the natural frequency is utilized, corresponding nodal support points are used. Conductive weights may be fixed to each end of tube 10 to add mass thereto. If the tube is mounted vertical, support at a single nodal point will suffice; in Fig. 5 (not shown) an elliptical tube (62) is held vertical by the capillary tube (64) used to admit the test pressure, the driving plates (68, 69) being located near the end of the tube adjacent the support. In a modification (Figs. 6, 7, not shown), a flattened tube (70) is supported vertical at a node by a capillary tube (71) and a tensioned wire (74), the tube being steadied at a lower node by pointed screws (84, 85) in supports (79, 80), which latter also provide mountings for driving plates (41, 44). If the driving-plates are displaced to one side of the longitudinal axis of the tube, the latter will vibrate in a torsional mode, either horizontally (Figs. 13, 14, not shown) or vertically (Figs. 15, 16, not shown); the support for the tube may be located at a point on the transverse axis or at points where the longitudinal axis bisects the ends of the tube (Fig. 28, not shown). By mounting dumb-bell weights to each end of the tube (Figs. 18-20, not shown), the weights being of a different metal from that of the tube, some temperature compensation is achieved. The vibrating tube may be filled with oil or other liquid (Fig. 21, not shown), the test pressure being applied to a diaphragm to compress the oil. An electromagnetic drive may replace the electro-static arrangement. In Figs. 9, 10 and Fig. 11 (not shown), respectively, the transversely vibrated tube comprises a tuning- fork and an inverted U-tube of magnetic material having in each case a driving and pick-up coil between the ends of its tines; in Fig. 22 (not shown) a U-shaped coil-bearing core has polepieces shaped to conform to one side of an elliptical tube of magnetic material to vibrate it torsionally. In a piezo-electric embodiment (Figs. 24-27, not shown) the vibrating tube is made of quartz with four longitudinal metallized strip electrodes, and is connected in a Pierce oscillator to determine the frequency of oscillation thereof. Instead of the test-pressure being admitted to the interior of the tube (in any embodiment), the tube may be sealed and supported within a housing to which the test pressure is admitted (Figs. 8A, 8B, 17, not shown); in Figs. 29-31 (not shown) an openended tube is supported at its nodes (for transverse vibration) by diaphragms, the portion of the tube between the diaphragms being enclosed in a gas-tight container for subjection to exterior pressure therein. Mono-crystalline semi-conductor material, e.g. Ge, Si, InSb, GaSb, SiC, may be used for the vibrating tube in some embodiments.

658,961. Cathode-ray tubes. RADIO COR- .PORATION OF AMERICA. Sept. 29, 1947, No. 26288. Convention date, Sept. 27, 1946. [Class 39 (i)] The target electrode of a cathode-ray storage tube comprises a conducting element, a first layer of insulating material and a second layer of insulation material joining the first layer to the conducting layer, electrons with a sufficient velocity impinging on and passing through the first layer to produce a trapped charge image which can be sensed by electrons impinging on said target with less than the said sufficient velocity. The target comprises a metal plate 1 having thereon a peaked layer 21 of high dielectric material of several times the thickness which stops electrons of less than 5000 volts e.g. a barium and strontium titanate mixture applied by settling from a suspension. A thin film of collodion is applied by immersing in water and applying a drop or so of collodion which spreads over the tops 5 of the titanate crystals. A silicon dioxide film 4 is formed by evaporation, and on subsequent heating the silicon dioxide layer settles on to the crystal peaks 5 and the collodion is evaporated. The target T is mounted in a tube 7 with two electron guns 8, 9 with corresponding electromagnetic or electrostatic scanning units 10, 11. Gun 8 produces an electron beam B1 having velocities greater than 5000 v., and gun 9 a beam B2 with velocities below 5000 v. The unit 10 of the put-on beam B1 scans radially from saw-tooth generators G1, rotation of the deflection yoke changing the radial direction and the unit 11 is connected to saw-tooth generators G2. Signals are applied to the put-on beam B1 in which the electrons are fast enough to penetrate the silica layer 4 and build up a charge image on the back of the silicate layer by secondary emission from the titanate layer 2, the secondary electrons being too weak to pass through silica layer. The take-off beam B2 liberates secondary electrons from the silica layer (which it does not penetrate) and requires a large number of scansions to remove the charge laid down by B1. Signals taken from the collector anode 12 or from the signal plate 1 are fed to a kinescope and built up to a bright image. The target may be photosensitive so that a map or printed information may be projected thereon, e.g..in a radar system.

PURPOSE:To increase the fetch angle and collecting stereoscopic angle of an X-ray in the state for horizontally holding a specimen in a scanning electron microscope by forming annular non-dispersion type detector and disposing it in the vicinity of an electron beam/route so that electron beam passes inside the detector. CONSTITUTION:Non-dispersion type X-ray detector 19 is formed annularly and disposed in the vicinity of electron beam route so that the beam passes inside the detector 19. A detector retaining plate 14 thermally integrally formed with an external cooling tank 15 is disposed, for example, between a specimen 12 in a specimen chamber 10 under an objective lens 6 and a magnetic pole 8 under the lens, and an annular semiconductor X-ray detecting element 19 of Si or the like deposited with Be thin film on the detecting surface thereof is buried on the back surface of the edge in a hole 18 for passing the electron beam as formed at the plate 14. Thus, the X-ray can be detected at an X-ray fetch angle near 90 deg. in narrow space without necessity of inclining the specimen 12, and X-ray collecting stereoscopic angle is increased to enhance the detecting sensitivity of an electron microscope.

1,070,878. Semi-conductor circuits. TEKTRONIX Inc. Jan. 7, 1966 [Jan. 19, 1965], No. 893/66. Heading H3T. In a pulse delaying circuit, particularly for use in a sampling oscilloscope, a ramp waveform 60 is generated by charging a capacitor 36 which is normally clamped by a gating transistor 18 having an anti-saturation circuit. Trigger pulses are derived at 48 from the Y deflection waveform at 46 and are differentiated at 50 before being used to trigger two tunnel diode bi-stable circuits 54, 26. The output from tunnel diode 26 turns off gating transistor 18 and allows capacitor 36 to charge via a constant current transistor 10 so as to provide a ramp waveform 60. When the ramp voltage 60 exceeds that of a staircase waveform from 64, comparator diode 62 becomes conductive, triggering a further bi-stable tunnel diode 68 the output from which is differentiated at 72 to provide a pulse at 82 which may trigger an avalanche transistor sampling circuit. The constant current via transistor 10 is arranged to arm the tunnel diode 68 so as to improve its triggering stability. The response of the gating transistor 18 is improved by an anti-saturation circuit 40, 28. The circuit is reset after a time, adjustable by switches 38, 86, by a monostable multivibrator 84. The comparison of waveforms 60 and 64 enables different portions of the vertical input signal waveform to be sampled at successive times. The sampled signals are stored and displayed as a lower frequency waveform on a cathode-ray oscilloscope.

952,985. Semi-conductor devices. TELEFUNKEN A.G. April 8, 1960 [April 8, 1959], No. 12491/60. Heading H1K. In a transistor, the base zone includes particles (e.g. copper atoms) in a concentration such that the rate of recombination of charge carriers is a maximum adjacent either the emitter or the collector zone and reduces to a minimum adjacent the other of said zones. The Figure shows a device comprising base zone 1, emitter zone 2 and collector zone 3. A recombination layer 4 is provided adjacent the emitter which has the effect of reducing the grounded emitter current amplification factor # to improve the operating cut-off frequency. Alternatively the recombination layer could be adjacent the collector to prevent overloading and prevent storage effects. The recombination layer may be provided by diffusion of copper or nickel atoms.

1,119,708. Transistor amplifying and oscillating circuits; remote control of radio receivers. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 15 Oct., 1965 [15 Oct., 1964; 13 Feb., 1965], No. 43799/65. Headings H3Q and H3T. An R.C. coupled transistor circuit which can be adjusted to act as either a high Q circuit or alternatively as an oscillator comprises a first transistor T 1 with its collector connected to the base of a second transistor T 2 . A phase-shifting feedback loop is provided between a further electrode of the second transistor and one of the first transistor, e.g. the network C, R 1 , R 2 connected between the emitters; the arrangement is characterized in that the collector circuit of the first transistor T 1 includes at least two semi-conductor diodes D 1 , D 2 connected in series and arranged in the same direction of conduction as transistor T 1 . The collector circuit also comprises phase-shifting elements, e.g. capacitor C 5 such as to cause a phase-shift equal to but of opposite sign to that of the feedback network at the resonance frequency of the circuit, which is also arranged so that at that frequency the loop gain is substantially equal to unity. The Specification gives mathematical expressions for the necessary conditions, which comprise the inclusion in the collector circuit of transistor T 1 of series resistor R 5 of value double the emitter input resistance of transistor T 2 : each of the diodes D 1 , D 2 should have the same value of differential resistance as the emitter input resistance of transistor T 1 , and this can be varied so as to change the resonance frequency of the circuit by adjustment of the emitter-collector current, by means of resistor R 1 . The value of capacitor C 5 determines the effective Q of the circuit; it is approximately half C, lesser values making Q negative, i.e. causing sustained oscillations to occur. The Specification describes numerous modifications to the circuit, including means for maintaining the resonance frequency constant despite temperature variations (Figs. 3-5, not shown) and the use of transistors to replace resistors R 1 , R 2 (Figs. 6 et seq., not shown); transistor T 2 may also be replaced by a Darling- ton pair (Fig. 6, not shown) and resistor R 5 by diodes (Fig. 7, not shown). Two such resonant circuits may be tuned simultaneously by means of a single variable resistor (Fig. 8, not shown) and may be adjusted so that their resonant frequencies differ by a constant frequency, thus providing gang-tuned input and oscillator circuits for a superheterodyne receiver. In alternative circuits the feedback loop is located between the collector of the second transistor and the base of the first (Figs. 9-13, not shown) and in these the phase-shift may be shared between two stages (Fig. 11, not shown). Transistors of different conductivity type may be employed (Fig. 13, not shown). The Specification also discloses the manner in which two such resonant circuits may be coupled together (Figs. 14, 15, not shown) and the use of a shunt diode in the coupling network to act as a variable impedance for the purpose of gain control (Fig. 17, not shown). The arrangement may be modified by the inclusion of resistance in series with the capacitance C 5 to compensate at high frequencies for the effect of the capacitance between emitter and base (Fig. 16, not shown). When the arrangement is used as local oscillator in a superheterodyne receiver, the frequency may be automatically controlled by a voltage depending on the detected signal; again, the resistor R 1 may be of light-dependent type and controlled, e.g., from a remote light source. In another, e.g. remote control circuit, a single variable resistor may be used to tune over a number of separate desired wavebands, intervening frequencies being excluded by providing gaps in the resistor track which are closed by means of fixed resistors (Fig. 18, not shown). The arrangement may also be used as an amplifier of the modulation type; e.g. a capacitance pick-up may be connected in shunt with capacitor C 5 to vary the circuit Q, i.e. provide amplitude modulation, or resistor R 1 may be varied as a function of the signal, to provide oscillations modulated in frequency and amplitude. In an alternative embodiment, a small part of the current flowing through resistor R 1 is diverted from transistor T 1 , through a signalcontrolled transistor T 5 (Fig. 19, not shown) and flows direct into the diodes D 1 , D 2 . The Specification also discloses modifications of the circuit in which the resistance R 5 is considerably increased in value, to reduce the effect of non- linearity in diodes D 1 , D 2 with appreciable signal amplitudes, resistance being connected in series with capacitor C in compensation (Figs. 20-22, not shown). In an arrangement for providing a high Q circuit of improved stability, a second similar circuit, adjusted just to oscillate, is also provided its output being detected and supplied as a Q control to both circuits.

Equipment for measuring distribution of void or particle size capable of measuring the size of a void or a particle in a short time with high accuracy. When the size of a void Y existing in a porous insulator film (3) or the size of a particle in a thin film is measured, a sample (5) having the insulator film (3) formed on the surface of a substrate (4) is irradiated, from the surface side thereof, with X-rays R at a specified incident angle thetai larger than the total reflection critical angle of the insulator film (3) but not exceeding 1.3 times the total reflection critical angle of the substrate (4). X-rays beamed into the insulator film (3) and reflected off the surface of the substrate (4) and not entering the void Y but exiting the insulator film (3) are a scattering component and such a scattering component as having a larger exit angle as compared with that when the reflecting component does not enter the void Y but exits the insulator film (3) is detected. La présente invention concerne un équipement pour mesurer la distribution de la taille des vides ou des particules, capable de mesurer la taille d'un vide ou d'une particule en un temps très court, avec une haute précision. Pour mesurer la taille d'un vide (Y) existant dans un film isolant poreux (3) ou la taille d'une particule dans un film mince, on prend un échantillon (5) constitué d'un substrat (4) à la surface duquel se trouve le film isolant (3), et on le soumet depuis sa surface à un rayonnement aux rayons X (r) selon un angle d'incidence theta i supérieur à l'angle critique de réflexion totale du film isolant (3) sans toutefois dépasser de 1,3 fois l'angle critique de réflexion totale du substrat (4). Les rayons X envoyés sur le film isolant (3) et renvoyés par la surface du substrat (4) sans entrer dans le vide (Y) mais ressortant du film isolant (3) sont une composante de dispersion. En l'occurrence, la détection porte sur une telle composante de dispersion dont l'angle de sortie est supérieur à ce qui se produit lorsque la composante se réfléchissant ne pénètre pas dans le vide (Y) mais sort du film isolant (3).