Qinetiq Limited

The Secretary of State for Defence in Her Britannic Majesty's Government

The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland

Metrasens Limited

Paul Antony Manning

Tej Paul Kaushal

John Peter Gillham

Gary Stacey

Mark N Keene

Rupert Nicholas Anderton

Rex Watton

Harvey N Rutt

Kevin James Palmer

Peter Georg Laitenberger

David Martin Pooley

Paul P Donohue

Kevin Palmer

An apparatus for detecting a moving ferromagnetic target object in a protected area comprises a first magnetic sensor adapted to measure a magnetic field within a first localised volume of space defined by a first zone of sensitivity of the first magnetic sensor and to produce a corresponding first measurement signal, and a second magnetic sensor adapted to measure a magnetic field within a second localised volume of space defined by a second zone of sensitivity of the second magnetic sensor and to produce a corresponding second measurement signal. The two magnetic sensors are separated spatially by a baseline such that the overlap between the two zones of sensitivity defines both a protected zone and a non-protected zone. A signal processing circuit is arranged in communication with the two magnetic sensors and is configured to process each of the first and second measurements signals to produce a respective first intermediate signal and a second intermediate signal which are each independent of the value of any non-changing background magnetic field that may be present in each zone of sensitivity, the value of the first and second intermediate signals thereby being dependent on the magnetic field associated with a target object moving in each zone of sensitivity. The first and second intermediate signals are proportional to the absolute change in magnetic field generated by the movement of the target object. The signal processing circuit also processes the two intermediate signals to provide an output signal that has a value that is indicative of whether the target object that caused the magnetic field is in the protected zone or in the non-protected zone.

Magnetic apparatus for protecting a protected area

An infrared detector comprising a plurality of bolometer detectors, bias circuitry for applying a bias to the bolometer detectors, and connectors for connecting the bolometer detectors together to form a network, wherein the bolometer detectors are arranged in an environment at substantially atmospheric pressure. A method for increasing the sensitivity of an infrared detector, having a plurality of bolometer detectors arranged in an environment at substantially atmospheric pressure so as to at least partly compensate for a reduction in the sensitivity of the infrared detector due to conduction of thermal energy from the bolometer detectors through the environment, the method comprising at least one of the steps of connecting the bolometer detectors together in at least one of series and parallel, and operating the bolometer detectors at a DC bias current.

Infrared detector

A focal plane detector for imaging objects within a scene and having integral processing means for detecting edges of objects within the scene. The focal plane detector comprises a plurality of detector elements arranged to measure the intensity of the electromagnetic radiation incident thereon and processing means integral to the focal plane detector for combining the intensity measurements so as to indicate the difference in the intensity of the electromagnetic radiation. The focal plane detector is arranged such that the output from the focal plane detector corresponds to edges of objects within the scene. The focal plane detector may be arranged to be sensitive to infrared radiation.

Focal plane detector with integral processor for object edge determination

A method of hermetically packaging an electronic device (), in an enclosure () comprising mutually inter-engageable first and second housing members (), comprising the steps of securing the electronic device () to the first housing member (), engaging the first () and second () housing members such that an hermetic seal is provided there between, wherein the engagement step is performed in a controlled atmosphere. The hermetic seal may be provided by an interference fit between the first () and second () housing members or via sealing means () interposed between the housing members (). The second housing member () may comprise an optical element (), for example a window or lens. The packaging method is particularly applicable to packaging thermal detectors, for example microbolometer arrays.

Hermetic packaging

A detection device that can be used for detecting objects behind clothing etc including a dielectric lens and a receive element sensitive to millimetre wave radiation. Prior art systems produce an image of a scene usually using scanning optics. This can be large and expensive. The present invention instead take spot readings from different parts of a scene without building up an image. The spot readings are processed, and an indication given to a user if certain characteristics of the readings are observed. Typical characteristics used are the differences in absolute received power level, and the power level at different polarisations. Such characteristics are typically present is an object of interest is in the scene. Also disclosed are various methods of altering the received beam to get readings from different areas from the scene, such as changing the beam width, or beam angle.

Millimetre-wave detection device for discriminating between different materials

An Array of detectors can be configured to be read as separate detectors, or to be connected into larger groups, e.g. groups of four (a 2&#xd7;2 array). This allows the formation of a relatively high definition image, and a much faster formation of a lower resolution image. This may be used with in an automobile to control deployment of safety airbags in accordance with a drivers position relative to the airbags. Preferably the array is a 64&#xd7;64 array of thermal detectors.

Reconfigurable detector array of resistance bolometers

An imager is disclosed comprising: one or more detectors, a shutter adapted to open and close periodically to modulate the radiation incident upon the detector element to produce a sequence of alternating open fields and closed fields, said detector being adapted to produce a first pair of output signals V and V comprising an open field and a closed field, and a second pair of output signals V and V comprising an open and a closed field, a reset device adapted to reset the output of the detecting element to a predetermined voltage after the output signals of V , V , V and V have all been obtained, there being no reset of the output of the detecting element between the output signals V , V , V and V , and a processor adapted to process said first and second pairs of output signals to produce a first and a second processed image signal from the detecting element, the first processed image signal corresponding to the first pair of fields and the second processed image signal corresponding to the second pair of fields. The four signals provide sufficient information to produce images,which are free from reset KTC noise whilst removing the effects of ramp voltages produced by current leakage across the detectors.

Image processing with modified ramp signal

A non-mechanical modulating device for use in infrared detection. The device is of particular use in the 8-14 &mgr;m range and has application in thermal imaging cameras and gas sensing systems. The modulator comprises a germanium element and a means of varying the carrier concentration. In particular, the variation of the hole concentration gives rise to the absorption of infrared radiation due to interband transitions between the light and heavy hole bands in the split valence band in germanium. The variation in hole concentration may be initiated in any convenient way, for example, by the irradiation of the germanium with visible or near infrared light, by the electrical injection of free carriers across a germanium diode structure or by electron impact on the germanium surface following acceleration under vacuum. In the case where the variation in carrier concentration is initiated by optical means, the surface of the germanium is treated so as to produce a low surface recombination velocity.

Infrared radiation modulating device

A thermal detector comprises a row of thermal detector elements each connected to a common bus line via the gate of a high impedance input preamplifier and a switch. The line output from the bus line is taken across a load resistance providing a common source follower load for the prepamplifiers. The signal across the load is passed through an anti-aliasing low-pass filter to a sample-and-hold. Signals then pass to a high-pass digital filter arranged to substract successive signals from each detector element corresponding to open and closed positions of a radiation modulator. This attenuates 1/f noise. The filters are located outside the row. Bulky filter components may accordingly be employed giving good noise performance without affecting detector element spacing. The preamplifiers and the switches are preferably MOSFETs. The detector may incorporate many rows of detector elements to provide a two-dimensional array.

Growing community of inventors

Malvern, United Kingdom

Paul Antony Manning