Abstract: A plasma-addressed electro-optic display device having a layer of electro-optic material, data electrodes coupled to the electro-optic layer and adapted to receive data voltages for activating portions of the electro-optic layer, and a plurality of plasma channels extending generally transverse to the data electrodes for selectively switching on the electro-optic portions. The plasma channels each contain spaced elongated cathode and anode plasma electrodes and an ionizable gas filling. The cathode and anode electrodes are arranged in groups to reduce the connections required. Reference voltages are applied to the grouped cathode and anode electrodes such that the data voltages required to operate the panel are reduced decreasing vertical crosstalk. Various driving voltage waveforms can be used for further crosstalk reduction, to reduce the number of voltage levels required, and cause the cathode and anode electrodes to exchange roles during operation to extend lifetime.

Abstract: A flat display device, preferably of the PALC type, in which the plasma channels are formed by etching laterally-spaced slots in a spacer plate, attaching a thin dielectric sheet over the etched spacer plate, and bonding the etched spacer plate to a transparent substrate such that each channel is formed by the portion of the substrate between flanking walls formed by the etched slots in the spacer plate, adjacent flanking walls in the spacer plate, and the overlying portion of the thin dielectric sheet. By positioning the flanking walls between channel electrode pairs, thus providing glass-to-glass interfaces, anodic bonding can be employed to assemble the three channel elements. Etching can be simplified by pre-attaching the unetched channel plate to the substrate or thin dielectric cover sheet with an intervening etch stop, and etching in situ using the etch stop to prevent etching of the substrate or thin dielectric cover sheet.

Abstract: A flat display device, preferably of the PALC type, in which the plasma channels are formed by etching in a substrate laterally-spaced channels and bonding a thin dielectric sheet over the etched substrate. Adjoining each of the channels are shallow ledges, also formed by etching, which serve as recessed areas to receive enlarged ends serving as contact pads for each of the electrodes. Holes are formed in the thin dielectric sheet and contact material deposited on the bonded thin dielectric sheet such that the deposited material makes electrical contact with the underlying electrode contact pads and seals off the holes, which allows a plasma-forming atmosphere to be provided in the channels. This arrangement results in a glass-to-glass interface between the substrate and the thin dielectric sheet, which allows anodic bonding to be employed to assemble the two elements and thus eliminates the frit glass sealing process required in other constructions.

Abstract: A plasma-addressed electro-optic display device having a layer of electro-optic material, data electrodes coupled to the electro-optic layer and adapted to receive data voltages for activating portions of the electro-optic layer, and a plurality of plasma channels extending generally transverse to the data electrodes for selectively switching on the electro-optic portions. The plasma channels each contain spaced elongated cathode and anode plasma electrodes and an ionizable gas filling. To improve performance, reliability and lifetime of the device, at least the cathode electrodes have surface portions of a negative electron affinity material. Preferably, the negative electron affinity material is a film of conductive or semiconductive diamond, diamond-like carbon, or aluminum nitride.

Abstract: A plasma-addressed electro-optic display device comprising a layer of electro-optic material, data electrodes coupled to the electro-optic layer and adapted to receive data voltages for activating portions of the electro-optic layer, and a plurality of plasma channels extending generally transverse to the data electrodes for selectively switching on said electro-optic portions. The plasma channels each comprise spaced elongated cathode and anode plasma electrodes and an ionizable gas filling. To improve performance and increase the effective aperture and provide a stable discharge, the channels are configured with a substantially flat bottom surface portion and curved side wall surface portions on which the electrodes are deposited such that the spacing between the electrodes is increased and the electrode surfaces form an angle of the order of 90.degree..

Abstract: A magnetic reading head having a magneto-resistive element of the type in which the measuring current is forced to flow through the element at an angle with the easy axis of magnetization. For suppressing thermal noise (resistance variations under the influence of temperature fluctuations as a result of the contact of the element with a moving record carrier), the element is subjected to an auxiliary field parallel to the easy axis of magnetization, the direction of which is reversed at a frequency f.sub.s. The measuring current alternates at the same frequency in phase with the reversals of the auxiliary field. The output signal of the element is applied through a low-pass filter which cuts off signals of a frequency f.sub.s to a detection device.

Abstract: Transmission system for signal transmission by means of compressed delta modulation provided with leaking integrators in the delta modulator and demodulator, the leaking integrator in the modulator being connected in series with the capacitor of large capacitance between the terminals of a signal source having controlled current sources for reducing the noise and distortion produced by the modulator.

Abstract: System for the vocoder transmission of speech signal with reduced bandwidth. The speech signal is split into a low-frequency part and a high-frequency part. The high-frequency part is subdivided into a number of sub-bands and for each sub-band a control signal with reduced bandwidth is transmitted. A control signal is representative for the ratio between the energy in the sub-band of the speech signal and the energy in the corresponding sub-band of a reference signal with high-frequency components, which is produced from the low-frequency part of the speech signal.

Abstract: A magnetic head for detecting information-representing magnetic fields on a magnetic recording medium and comprising an elongate magneto-resistive element of a magnetically anisotropic material which at its ends has contacts for connection to a current or voltage source. In order to linearize the playback characteristic of the element, the easy axis of magnetization coincides with the longitudinal direction of the element and means are present which force the current to travel at an angle of minimum 15.degree. and maximum 75.degree. with the longitudinal direction. These means consist in particular of equipotential strips provided on the element.

Abstract: Resistance read amplifier in which a resistor the resistance of which is to be determined is connected by an electronic selection switch to a constant-current source which at the same time switches an associated output amplifier into circuit.