Abstract: An electrooptical cell has electrical connection means between electrodes and a control unit which comprise a contact block of a synthetic adhesive material having conducting particles applied on the edge of each plate in contact zones which are provided flush with said edge, the contact block constituting both the electrical connection and the mechanical bond with at least one other element of said connection.

Abstract: A cathodic sputtering operation using a target of a material containing titanium, aluminium, oxygen and nitrogen in an argon atmosphere is disclosed.This sputtering operation gives rise to a layer containing the same elements as the target. The resulting layer is opague, has an attractive, deep and brilliant black color, adheres well to the substrate and is resistant to wear and corrosion. The physical structure of the layer is characterized by a transparent and insulating amorphous phase in which are dispersed a plurality of inclusions having a size on the order of nanometers.

Abstract: A cathodic sputtering operation using a target of a material containing titanium, aluminum, oxygen and nitrogen in an argon atmosphere is disclosed.This sputtering operation gives rise to a layer containing the same elements as the target. The resulting layer is opaque, has an attractive, deep and brilliant black color, adheres well to the substrate and is resistant to wear and corrosion.

Abstract: An optically pumped laser comprising a securing arrangement (14) for the bar assuring, on one hand, the rigid interconnection of the bar (4) and the framework (12a, 12b, 12c, 12d) by gripping the former and in bearing on the latter and, on the other hand the thermal insulation of the lateral faces of the bar. The securing arrangement (14) is obtained from an elastically deformable fitting of plastics material.

Abstract: The invention discloses an optically pumped laser comprising suspension means (7) for the bar (2) having inherent elasticity for assuring elastic gripping of the latter. The suspension means (7) comprise at least two suspension elements (17a, 17b) having a generally planar form extending parallel to the pumping faces of the bar. Each suspension element exhibits at least one peripheral securing zone (19a, 19b), a central clamping zone (20a, 20b) and an elastically deformable intermediate zone (21a, 21b) coupling these latter.

Abstract: A device for displaying the value of a quantity represented by input data comprises a mobile indicator member (24) driven by a stepping motor (20), a control circuit (18) for this motor for delivering drive pulses to the motor in response to the input data to move the indicator member to a position corresponding to the value of the quantity, and a dial (26) for showing an indexing system, for example a scale, which cooperates with the indicator member to indicate the value at least approximately. The dial comprises a liquid crystal, electrochromic or electroluminescent electrooptical display device (26) which displays the indexing system in response to signals from another control circuit (28) when the latter receives an activation signal. The device enables values of a single quantity situated in different ranges or values of distinct quantities to be indicated, by making the cell selectively display corresponding indexing systems. A specific application of the device is for automobile dashboards.

Abstract: An echo tracker clamps a time window for detecting an echo at the position of an echo produced by a mobile wall receiving an ultrasonic pulse signal at a repetition rate F.sub.r. It includes a depth counter (28) which counts in order to define the beginning of the time window in relation to a pulse of the pulse signal and which when it reaches a given value, supplies an enabling signal to activate authorization means (30) and a position detector (32).Enabling means (30) provide an enabling signal for a given time which defines the detecting time window. During this time, the position detector counts until the echo is detected. The value reached at that instant is used to clamp again the time window and to modify the initial value of the depth indicator.The invention is useful in the medical field for measuring the changes of the position of an interface between two tissues.

Abstract: The invention concerns a device for measuring a physical quantity, for example a force (A), and providing an output signal (Vs) whose amplitude represents the measured value. The device comprises a first oscillator (1) including a resonator (3) to which the force (A) is applied, this oscillator delivering a first alternating signal (S1) whose frequency depends on the magnitude of the force (A), a second oscillator (2) supplying a second alternating signal (S2) whose frequency is determined by the amplitude of the output signal (Vs), an EXCLUSIVE OR gate (20) receiving the first and second signals, and a low-pass filter (21) delivering the output signal (Vs) in response to a signal supplied by the gate (20). The amplitude of this output signal depends on the phase difference of the first and second signals, and constitutes a measurement of the magnitude of the applied force (A). The device is advantageously used when the measurement is to be displayed in analog form.

Abstract: The described cell comprises a mixture of liquid crystals (26), polarizers (28, 30) and alignment layers (22,24). The liquid crystals mixture includes a chiralic compound which induces a helical structure having a pitch greater than or equal to the thickness of the liquid crystal layer. One alignment layer (24) induces a planar alignment, the other (22) induces a hemeotropic alignment. This cell, of low cost, requires low control voltage and provides a very good contrast and a high multiplexing rate. It may be used to advantage in the manufacture of dots matrix display watches.

Abstract: In a reflector-diffuser type liquid crystal display cell, the control electrodes, which are transparent, electronic components and tracks connecting the components to the cell terminals are disposed between the cell front plate and the liquid crystal layer. The counter electrode is disposed on the other side of the liquid crystal layer and has a frosted rough light reflecting and diffusing face over its entire surface situated in the display area and thus itself functions as the cell reflector-diffuser.

Abstract: A barrel spring winding device comprises a solar cell (3) arranged to receive ambient light, a capacitor (4) connected to the terminals of the cell, a stepping motor (6) and a control circuit (5). The input of the circuit is connected to the terminals of the capacitor and its output to the terminals of the motor. The rotor of the motor is operatively connected to wind a barrel spring, for example of a watch. The cell (3) charges the capacitor (4) and when the voltage thereof, measured by a differential amplifier (23), reaches a reference voltage (V.sub.r), the capacitor is connected to the terminals of the motor by a switching transistor (27). Discharge of the capacitor supplies to the motor a drive pulse whose duration is determined by a one-shot flip-flop (25). After the pulse, the capacitor is once again charged by the cell. To prevent the motor from receiving a drive pulse before it has stopped, i.e.

Abstract: A laser includes a discharge tube formed from one piece and penetrating, with play, into an anode chamber on one side and into a cathode chamber on the other side, the anode and cathode chambers having a thermal expansion coefficient different from that of the discharge tube. Bellows are hermetically welded by their first ends to the anode and sealed by a glass bead to the discharge tube at their second ends.

Abstract: A composite material comprising an open pore rigid foam of ceramic, metal, carbon or a plastics material and a solid filler material disposed in the cavities of the foam. The solid filler material forms areas on the surface of the composite material defined by the walls of the cavities in the foam. Depending on the material of the foam, the material filling its cavities may be a metal or a plastics material. The composite material, the production of which is also described, has aesthetic qualities which render it particularly suitable for the production of decorative articles.

Abstract: The method of this invention includes measuring the quantity Eme of electrical energy converted into mechanical energy by the motor during a driving pulse, determining the time required for said quantity of energy to attain a reference value E.sub.ref and interrupting the driving pulse as a function of such time.The arrangement includes means for measuring said quantity Eme of energy, means for determining the time required for such quantity of energy to attain such reference value E.sub.ref and means for effecting interruption of the driving pulse as a function of such time.

Abstract: The gas laser of this invention includes a discharge tube formed from a plurality of metallic bodies arranged in end to end alignment. The tube is terminated by a cathode chamber at one end and an anode chamber at the other end. Each of the metallic bodies and the cathode and anode chambers is provided at least with one tubular element said elements being joined together by means of a glass welding bead. The material forming said tubular elements has the same coefficient of thermal expansion as glass. The invention finds particular application to completely sealed lasers.

Abstract: The article is provided with a coating resisting wear and corrosion, such coating being for the most part made of a precious metal or alloy of a precious metal, for example gold or an alloy containing gold.The coating is made up of a first layer of such precious metal or alloy thereof comprising discrete inclusions of a metallic compound such as titanium nitride. These inclusions are deposited along with the precious metal in vapor phase and distributed in a substantially homogeneous manner through the entire thickness of the layer, said thickness being equal to or greater than 0.4 .mu.m. A second layer of precious metal or alloy thereof is located between the article and said first layer.The article may be a watch case, a bracelet link or a piece of jewelry.

Abstract: A force sensor comprising a resonator (10) having a frequency that varies with the force being measured. The resonator includes an oscillatory bar (101, 102) and a pair of anchor members (12, 103, 104) that are connected each to a corresponding end portion of the bar and which are adapted to apply the force having to be measured to the bar. The sensor further comprises a tube (16) that surrounds the resonator and which is rigidly secured by its end portions to the anchor members (12).

Abstract: In a gas laser including a discharge tube forming a resonant cavity, a mirror disposed at each end of the cavity, a pump, a gas source and a manometer, a first valve is connected between one end of the tube and a first of the mirrors and a second valve is connected between the other end of the tube and a second of the mirrors. Within the body of each valve is a moving element which may assume a first working position, a second position permitting mirror access and a third position for changing gas. This arrangement permits changing mirrors and/or replacing gas without exposing the cavity to atmospheric pressure and without loss of time.

Abstract: The method according to the invention is applicable to motors comprising a magnetized rotor having two diametrically opposed poles, a stator making up a magnetic circuit having saturable constricted portions and a coil coupled magnetically to the stator. The method consists in applying to the coil an electric pulse, in measuring a control current (I'.sub.01, I'.sub.02) generated within the coil by the electric pulse at the end of a control time interval (t'.sub.o -t.sub.i) and in comparing the control current with a reference current (I.sub.r), the sign of this comparison being representative of the position of the rotor. In order to take into account the variations in the characteristics of the motor with time, the control time interval (t'.sub.o -t'.sub.i) is readjusted periodically by means of first and second electric pulses of a learning signal applied to the coil. The first pulse of this signal generates within the coil a first current (I.sub.1) which reaches the reference current (I.sub.

Abstract: A pager is described for use in an electronic watch. The pager comprises a frame (1) for picking up a magnetic signal and a piezoelectric transducer (11) having a static capacitance on its terminals, for producing a sound. 11To improve sensitivity of reception, a switching circuit (15) connects the transducer (11) in parallel with the frame (1) to tune it by means of the static capacitance to the frequency of the magnetic signal carrier wave. To increase the performance of the transducer (11 ) when it operates as a sound transmitter, the switching circuit (15) connects the frame (1) in series with the transducer (11).