Abstract: An apparatus is disclosed for monitoring usage of multiple electrical devices. The apparatus comprises multiple non-invasive current sensors for sensing current in respective conductors associated with the electrical devices. Such conductors may for example be the electrical power supply leads to the devices. The apparatus further includes multiple analogue to digital conversion functions for digitizing the output from the respective current sensors. A microprocessor is arranged to receive the digitized current sensor and is programmed to create usage data relating to the respective electrical devices. Such usage data may include cumulative elapsed running time. The microprocessor has an associated memory in which the usage data is stored in association with corresponding data identifying the electrical devices. The system further includes an interface through which the usage and identifier data are extractable, to provide usage information for the respective electrical devices.

Abstract: A method and control circuit are disclosed for controlling light emitting diodes (“LEDs”). Based upon the LED's current versus intensity characteristic and temperature versus intensity characteristic, the rate of change of LED output intensity with respect to current is calculated. Adjusting LED current to provide zero rate of change ensures that LED output is maximised.

Abstract: The invention concerns a light source utilizing an array (20, 50) of light emitting elements (22). The elements may be light emitting diodes. A fresnel prism (32, 56) is disposed in front of the array to receive light from it. The prism serves to divert light from the array along a direction (28, 54) oblique to the array, the diverted light forming an output beam. The array has a depth. The output beam from the prism has a depth which, measured in the same plane as the array depth but perpendicular to the beam direction, is smaller than the depth of the array. Hence a deep array provides a shallower output light beam in a manner which is convenient with regard to packaging requirements.

Abstract: A monolithic capacitor array (18) is disclosed which may be suitable for incorporation into a multi-way electrical connector and comprises a dielectric body (20)with a set of through-going cavities (22) for receiving respective connector pins. The cavities are associated with respective capacitors (30, 32) each formed by a first and a second set of capacitor plates (38, 40, 44, 46) interleaved within the dielectric body. The first set of capacitor plates is connectable to ground through a contact (42) at the body's exterior. The second set of capacitor plates is interconnected by metallization of the interior of a connection cavity (62) formed in the dielectric body, the connection-cavity being separately formed form its associated pin-receiving cavity and the metallization therein being contactable from the body's exterior to enable connection of a pin received in the pin-receiving cavity to the second capacitor plates of the associated capacitor.

Abstract: An LED drive circuit is disclosed, comprising an electronic controller which is arranged to monitor LED current as a first input. The controller also receives a second input from a sensor associated with the LED. The controller serves to monitor, based on its inputs, at least one further operating parameter of the LED which is either LED junction temperature or LED luminous intensity. The further operating parameter may be directly sensed by the sensor or may be calculated from the inputs to the controller. The controller is adapted to implement a closed loop control on LED current and to thereby limit current as necessary to maintain both the LED current and the further operating parameter below predetermined maximum values.

Abstract: A data indicator is disclosed which comprises a non-volatile memory (26), control circuitry (24) by which data can be read from and written to the memory, a timer (28) and/or an event detector (30), means such as a terminal (20) for connection to an electrical supply of a host apparatus and an interface (32) through which data can be exchanged with the memory (26). In use, the event detector (30) detects when the host apparatus is switched on and in dependence on the detector output the control circuitry (24) maintains a cumulative history of host apparatus activation which is stored on the memory (26). The data indicator can store other data relating to the host apparatus, e.g. a service interval, and can supply this in conjunction with the actuation history, making it conveniently possible e.g. to establish whether the host apparatus requires servicing. (FIG. 4).

Abstract: An LED package having a generally tubular electrically conductive body, a circuit board which is mounted across the body at or adjacent one end thereof and which has an outer face on which an LED is mounted, an end contact exposed at the end of the body remote from the circuit board and located relative to the body by means of an insulating cap mounted across the body. An electrical conductor extends from the end contact through the cap, through the interior of the body and through the circuit board to connect the end contact to one of the anode and the cathode of the LED. An electrically conductive path is formed on the circuit board to connect the other of the anode and the cathode of the LED to the body such that the body serves as a second contact enabling current to be supplied to the LED.

Abstract: A light is disclosed which may be an aircraft light, comprising a base 2 for mounting the light, a chassis 8 upstanding from the base, a circuit board 10 mounted upon an outer face of the chassis and at least one solid state emitter—and more preferably an aray of LEDs 24, 26—mounted upon the circuit board. The invention provides a light which is constructionally convenient but can provide a clean beam pattern.

Abstract: An equipment label comprising an identity plate bearing information markings and an electronic tag having electrical contacts. The identity plate is provided with means for attachment to an item of equipment and is adapted to mount the electronic tag such that in use the label can be attached to the item of equipment with the identity plate's markings exposed to be read and the electrical contacts accessible for communication with the tag.

Abstract: An electrical connector comprising an at least substantially helical winding shaped to provide a first portion, having a diameter suitable to receive and embrace an electrical contact when inserted therein, and a second portion of larger diameter than the first for contacting an electrical terminal when disposed around or adjacent the contact, to thereby form an electrical connection from the contact to the terminal.

Abstract: An identification device comprising an IR LED contained within a housing which is adapted to be carried externally by a person or object who or which is to be identifiable in dark conditions. In cases where the device is to be used as a personnel identification beacon (PIB) the housing can carry means to enable it to have a "stick-on" capability whereby the housing can be easily attached or detached to/from the external clothing of a wearer. The IR LED can be adapted to flash and this can be in a coded sequence to enable the particular wearer to be identified.

Abstract: A multilayer discoidal capacitor having a plurality of laterally spaced, planar electrodes disposed within a dielectric body and configured such that the capacitance characteristic of the capacitor is determined at least in part by the concentrated charge distribution in the "stray" electric fields arising between the edges of the electrodes and at least one cylindrical electrode extending perpendicularly to the planar electrodes.

Abstract: A ceramic package component has a base portion and an upstanding enclosing wall on the base portion, the upper surface of the wall being provided with an electrically conductive coating in order to receive a lid sealingly thereon. The electrically conductive coating on the upper surface of the wall is electrically connected to a further conductive coating on the undersurface of the base portion by means of a high density array of conductive vias extending through the wall. The inter via spacing between adjacent vias is preferably less than one quarter of the wavelength of the frequency at which the component is to operate.

Abstract: A sealed LED lamp housing includes a single unit made of a semi-transparent polymer of neutral optical density having a first portion forming a lens, through which light can pass from an LED contained therein, and a second portion, of greater thickness than the first portion, that provides a contrast annulus surrounding the lens.

Abstract: A multiway connector assembly comprising a tubular metal outer casing, a plurality of electrical lead-through terminations which extend through the outer casing, the terminations being coupled to respective pi-section filters, each of which is formed by two annular discoidal capacitors separated by a tubular inductive element. The outer electrodes of the capacitors of the pi-section filters are connected to metal earth planes which are held in the outer casing by a first releasable retention clip such as to be in electrical connection with the casing. The inner electrodes of the capacitors are connected to associated ones of the terminations by way of respective contact clips which enable relative displacement of the capacitors and terminations for purposes of assembly and disassembly.

Abstract: A sub-sea fiber-optic cable location indication apparatus wherein a small portion of a light signal carried by a main optical fiber cable is tapped off and is used to trigger or control a parameter of an electromagnetic, or acoustic signal radiated by a transponder carried by the main cable.

Abstract: A multi-way connector assembly comprising a tubular metal outer casing and a plurality of electrical lead-through terminations which extend through the outer casing, the terminations carrying respective annular discoidal filter capacitors whose outer electrodes are connected electrically to a ground plane in the form of a metal plate which is itself connected electrically to the outer metal casing. The inner electrodes of the capacitor are electrically coupled to the associated lead-through terminations by respective contact clips which enable relative displacement of the capacitors and terminations for purposes of assembly and disassembly, the metal plate forming the ground plane being held in electrical connection with the outer casing by means of a removable locking means.

Abstract: A metallizing paste capable of being used for screen printing applications which comprises tungsten powder and an organic vehicle system. The organic vehicle system can comprise a polymeric material, such as ethyl cellulose, and a solvent, such as terpineol and the paste preferably includes frit material, of alumina, cerium fluoride, bismuth oxide and silica and may also include manganese and/or nickel.There is also disclosed a semi-conductor package made using the metallization paste. The package includes conductive attachment area, conductive feed-through paths, conductive vias and a conductive external underside, all of which are formed using the metallization paste in various formulations.

Abstract: An indicator lamp comprising a tubular housing which is closed at one end and has a light source disposed within it at a position remote from its open end. A diffusing screen is disposed within the tubular housing in front of the light source and again remote from the open end of the housing. The internal surfaces of the tubular housing between the location of the light source and the open end of the housing are blackened. A transparent lens is disposed adjacent the open end of the tubular housing and carries on its side closest to the light source an infra-red suppressing filter, and, on its side remote from the light source, an anti-reflection coating.