Abstract: Electromagnetic radiation is modulated in response to an electrical signal which produces a variable electric field in a semiconductor .delta.-doped structure. A resulting device has a desirably broad wavelength range in which light intensity can be modulated, large contrast ratio between transparent and opaque states, small operating voltage, and high-speed capability as desirable in optical communications applications.
July 21, 1988
Date of Patent:
May 29, 1990
American Telephone and Telegraph Company
Abstract: This invention relates to a device for electrooptic modulation of an optical beam. The device is a laminate comprising a coherent film of a conjugated polymer having semi-conducting properties as the active component laminated with two or more layers of electrically conducting, insulating or semi-conducting materials. At least the active component in the laminate is capable of interacting with the optical beam when under the influence of an electric signal and thereby result in a modulated beam. Means are provided for (i) establishing electrical contact with one or more layers of the laminate so as to enable an electrical signal to be applied across the active component and (ii) detection of the extent of modulation of the modulated beam emerging from the active component layer.
May 20, 1988
Date of Patent:
May 8, 1990
The British Petroleum Company p.l.c.
Philip C. Allen, Jeremy H. Burroughes, Richard H. Friend, Alan J. Harrison
Abstract: For charging an electrochromic layered package with hydrogen and for applying a backing to a layered package comprising a transparent substrate plate disposed on the front, at least two electrodes, where, of these two electrodes, the first electrode after this substrate plate (first electrode) is a transparent electrode, at least one electrochromic layer, a hydrogen-storing layer, a hydrogen ion-conducting layer and a backing which seals the layered package and directly follows the second of the two electrodes, an electrochromic layered system is initially, before application of the backing and after application of the second electrode, which is to be followed by the backing, electrolytically charged, in a first step, with hydrogen from a hydrogen ion-containing electrolyte solution and, in a second step, a metal layer is deposited reductively, preferably electrolytically, as a backing which provides sealing against H.sub.2 loss and H.sub.
Abstract: In an automotive mirror using an electrochromic element, the electrochromic element comprises a first electrode made of a transparent conductive layer laminated on a substantially rectangular glass substrate, two EC (electrochromic) layers disposed opposing each other with a solid electrolyte layer placed between them, a second electrode made of a reflective metal film and an insulative/protective layer disposed outside the second electrode. There are formed on the first electrode longitudinally and laterally in positions off the adjoining EC layer, strip-shaped metal films considerably superior in conductivity to the first electrode.
Abstract: Apparatus and method is disclosed for forming an elliptical surface in a mirror 10. The mirror blank is rotated about a given axis and the cutting tool tip 24 is pivoted about an axis C which is generally perpendicular to and spaced from the workpiece axis 16. As the cutting tip 24 moves in an arcuate path about point C the instantaneous radius R between the cutting tip and the C axis is adjusted by way of a linkage 34 which translates movement generated by a cam surface 36 and follower arm 32 into horizontal movement of the tool cutting tip 24.
Abstract: A device is provided forming a strictly ring interferometer having a ring formed by a monomode fiber, a source, separation and recombination means, and a monomode fiber segment forming mode filter. According to the invention, this monomode fiber segment is provided with a shutter generating directional losses intercepted by an optoelectronic detection member.
Abstract: A photometric measuring apparatus having a measuring chamber which can be cut off from extraneous light when a sample vessel is inserted and removed from the open end of the measurement chamber. A plunger, having a light-tight seal, movable vertically and horizontally on a pivotable arm driven by a drive mechanism for sealing the measuring chamber after a sample vessel is inserted in the measuring chamber. A guide means comprising a cylindrical guide tube having a guide groove on its surface which acts as cam means for controlling the vertical and horizontal movement of the plunger. The drive mechanism includes a drive motor and photocells for controlling the drive of the motor and vertical movement of the plunger and drive of the motor until the sample vessel upon which measurements have been completed are removed. The drive motor is spring mounted and actuates a microswitch to interrupt the motor drive when the drive is obstructed by the operator.
Abstract: The positive and negative outputs of an operational amplifier are employed to drive two oppositely phased current mirror circuits, which in turn drive oppositely phased power amplifier stages which drive the load directly without the use of an output transformer. Negative feedback is provided from the output to the operational amplifier to enhance flat response over the frequency range of interest. The oppositely phased power output stages are supplied by a power source which provides positive and negative supply voltages with reference to reference "ground". A plurality of capacitors are selectively connected as need be between the positive and negative voltage busses and ground to bypass spurious high frequency oscillations. A relatively high voltage output is achieved from the amplifier without exceeding the breakdown voltages of the transistors by employing a plurality of cascaded "Darlington" type circuits in the power amplifier.