Abstract: An imaging arrangement combines a thermal imager with a laser imager to enable several correlated pictures to be produced which show different properties of the same field of view. A common scanning device is used to scan each pixel in the field of view in a raster-like pattern, and for each pixel data can be derived representing thermal content, range, optical reflectivity and velocity. The last three properties are obtained by coupling an optical interferometer to the scanning device which generates the picture representing the thermal content.

Abstract: A two-colour radiation detector (2) comprises a mesa-type multi-layered mercury-cadmium-telluride detector structure monolithically integrated on a substrate (6). The detector (2) is responsive to two discrete wavelength ranges separated by a wavelength range to which the detector (2) is not responsive.

Abstract: An aperture arrangement is disclosed, such as an aperture arrangement suitable for use with a dual wavelength infrared detector. A detector is disclosed which includes a casing; an aperture defined in one end of the casing; and a filter having an inner region and an outer region substantially (e.g., greater than 50%) covering the aperture; wherein the outer region of the filter transmits radiation within a first range of wavelengths and reflects radiation within a second range of wavelengths.

Abstract: The present invention relates to an optical parametric oscillator. In particular, the present invention relates to a more optimal rotating image optical parametric oscillator. More specifically, there is described an optical parametric oscillator comprising six mirrored surfaces; wherein two of the mirrored surfaces are provided by a penta prism and the sequence of mirrors is operable to provide a predetermined rotation of a beam passing therethrough.

Abstract: This invention relates to a radiating element 20 for use in array antennas. The radiating element 20 is of simplified design and comprises a front region 26 and a rearward region 28 that are preferably substantially rectangular, which permit higher frequency limits than more conventional Vivaldi elements while maintaining the lower frequency limit. Additionally, by deployment of an array of a plurality of such elements 20 such that no gaps are formed between adjacent elements 20 along the array antenna, very wide bandwidth can be obtained using the array.

Abstract: Described herein is a multi-color radiation detector that comprises a mesa-type multi-layered mercury-cadmium-telluride detector structure monolithically integrated on a substrate. The detector is responsive to three or more discrete wavelength ranges and means is provided whereby each of the wavelength ranges can be detected independently or in combination with others of the ranges.

Abstract: A specialist tow cable termination for sustaining the tensile load when an object is towed at high speeds at the end of an cable behind an aircraft, the termination comprises a closed eye bolt attached to the cable and a U-bolt looped through the eye bolt attached to the object. The arrangement allows significant pivoting bending stresses to the tow cable.

Abstract: A transmitter (106, 120, 118, 122 and 110) of a platform (100) is arranged to generate a transmission pulse which is transmitted to a receiver (212, 224 and 208) of another platform (200) and is also arranged to couple its transmission pulse to a digital receiver (104) associated with its platform (100) via attenuater (126) and coupler (124). The other platform (200) performs a similar task. Each digital receiver (108, 208) determines the time separation between its transmission pulse and received pulse from the other platform (100 or 200). The determined time separation information is shared with the other platform (100, 200) and each digital receiver (108, 208) then determines a time offset (?t) between the time at its platform (100) and the other platform (200).

Abstract: Described herein is a towed body (10) having a deployment mechanism (18, 20, 22, 28) for deploying a drag cone carried thereby. The towed body (10) comprises a body portion (12), a nose portion (14) and a tail portion (16). The deployment mechanism comprises a slider (20) mounted on the body portion (12) to which are pivotally mounted a plurality of forward opening blades (24). The slider (20) has a clip (22) mounted within it for locking the blades (24) in the fully deployed position. The slider (20) abuts a hub (18) for providing a surface on which the fluid acts as the towed body (10) is being towed therethrough. From a stowed position, fluid acting on the hub (18) forces the slider (20) and the blades (24) to move towards the tail portion (16). The blades (24) move up and over a bumper (28) located adjacent the tail portion (16) to deploy from the stowed position. When the blades (24) are fully deployed, the clip (22) engages with the body portion (12) to lock the blades (24) in position.

Abstract: A microwave, power splitter/combiner (20) is formed as part of a multilayer laminate (27, 28, 29, 33, 34) such that two ports (22, 23) are connected by plated vias (31, 32) to conductive pads (29, 30) connected across an isolation resistor (27). Furthermore, a microwave circuit is provided in the form of a multi-layer laminate including a substrate carrying a resistive layer which has been etched to define at least one resistor, a dielectric membrane covering the resistor, a conductive layer defining at least part of an electrical circuit, and said at least one resistor is electrically connected to the conductive layer by vias extending through the dielectric membrane.

Abstract: A target tracking device incorporating a Position Sensitive Detector (PSD) 1 is described. A target is illuminated by a laser of a suitable wavelength. The target reflects the laser radiation and the reflected radiation is incident on a flying vehicle carrying a target tracking device. The PSD in the device outputs a signal representative of the position of the incident laser spot. The output signal is input into control electronics, the control electronics incorporating a resistive transimpedance amplifier. A higher than usual bias voltage is applied to the PSD yielding improved pulse response of the target tracking device. Therefore, the tracking device is particularly suited for use with a target marking laser having a short pulse duration.

Abstract: The present invention provides a kinematic mounting apparatus comprising: a plurality of spherical mount means; and a plurality of grooved mount means; wherein said mount means are operable to support a platform. The present invention relates to adjustable mounts. In particular, the present invention relates to mounting arrangements for optical devices requiring linear and tilt adjustment whereby a platform, which is usually either a mirror or a support for a mirror, should remain in a stress free condition at all times.

Abstract: The present invention relates to a mirror mount. In particular, the present invention relates to a two-axis mirror flexure mount with increased stiffness in all but the desired degrees of freedom. The present invention recites an integrally formed support for a mirror comprising; a rigid portion; a plurality of base portions suitable for mounting the mirror thereto; and a plurality of substantially linear flexure elements provided substantially perpendicular to one another and disposed between the mount portion and the base portion to connect the mount portion and the base portion together; wherein the flexure elements each define an axis of rotation and are operable to allow the mount portion to rotate relative to the base portion along either said axis of rotation.

Abstract: The present invention relates to an actuator. In particular, the present invention relates to an actuator having improved acceleration for payloads at an optimum volume and mass of actuator. Specifically, the present invention relates to an actuator comprising a field structure assembly comprising an arrangement of permanent magnets and magnetically soft components, and a moving coil assembly, wherein the arrangement of permanent magnets comprises a conical magnet and a plurality of segmented ring magnets.

Abstract: A cationic oligomer of a saccharide, wherein the saccharide is functionalized by a cationic group, for example an ammonium, phosphonium, imidazolium, or pyridinium group. In a preferred embodiment, the cationic oligomer of a saccharide is a cationic cyclodextrin. There is also provided a use of the cationic oligomer of a saccharide as a chiral agent for resolving enantiomers by a chromatographic method or an asymmetric synthesis.

Abstract: A continuous wave ranging system, comprising a modulator 2 for modulating an r.f. carrier wave in accordance with a pseudo random code, a transmitting antenna 5 for radiating the modulated signal towards a target, a receiving antenna 6 and receiver 7 for detecting the signal reflected back from the target, a correlator 8 for correlating the reflected signal with the transmitted code with a selected phase shift corresponding to the current range gate to be tested, whereby the range of the target from the system may be determined, a store 12 containing a plurality of different pseudo random codes, and selector means 13 arranged to supply to the modulator 2 and to the correlator 8 a code from the store 12 which code does not produce a breakthrough sidelobe in at least the next range gate or gates to be tested.

Abstract: A reference surface for calibrating cooled infra red detectors includes a plurality of corner cube units which reflect radiation incident directly on them. The surface of each corner cube unit is partially reflective and partially emissive such that, when imaged by a cryogenically cooled detector, the reference surface appears as a black body source at a lower temperature than the actual temperature thereof.

Abstract: This invention relates to reducing the complexity and cost of antenna arrays and is more specifically concerned with reducing the complexity of an antenna apparatus (10). It provides an antenna array (62) made up of a vertical stack of horizontal linear structures (74) each having several groups of neighbouring array antenna elements (78), the groups (74) having variable numbers of the antenna elements (78) each connected to a transmit/receive module (66). The advantage of this configuration is that less communication modules (66), such as transmit/receive modules, are required to operate the antenna array (62), reducing the weight, power consumption and cost of an antenna apparatus (10) incorporating such an antenna array (62) without significantly limiting the capability and/or performance of a system compared to a conventional solution.

Abstract: A quadrant detector includes a holographic optical element and a plurality of detector elements. The holographic optical element is designated to have four quadrants, each of which directs radiation incident thereon to an associated detector element. Signals from the detector elements are processed individually to optimise the performance of each detector element.

Abstract: Described herein is a latch circuit (110) which has an improved maximum toggle rate or frequency. The latch circuit (110) includes a first portion (116) and a second portion (62) in which input clock signals (52,54) are applied to respective input transistors (118,78). The input transistor (118) for the first portion (116) has an emitter area which is double that of the input transistor (78) for the second portion (62). This ‘imbalance’ between the two input transistors (118,78) provides an increase in the ‘hold period/follow period’ ratio such that it is greater than 1, the self-resonance of the latch circuit (110) and also maximum toggle rate or frequency.