Abstract: Preprocessor for the detection of point sources in an infrared (IR) "scenario" or field, essentially consisting of an input interface; a transversal filter; an adaptable threshold device, consisting in turn of a two-port internal memory and of an arithmetic processing unit; a resource assembly and an output interface. The system can be used in surveillance in the IR band, more particularly, in the field of detection of signal emission on ships, planes, helicopters, transportation means, armored cars, airports and anywhere it is necessary to detect artificial or natural heat sources from as far away as possible. In comparison with the prior art, the preprocessor differs from the point of view of the filtering system, adjusting the filter itself to the real form of the IR signal which is punctiform and depends on the electro-optic characteristics of the sensor.

Abstract: A damper, especially for a structural element of an aircraft and especially a propeller driven aircraft in which the propeller generates vibration in the structural element with a fundamental frequency and a frequency which is a harmonic of the fundamental frequency. The damper has a cantilever bar which can be flexed and a cup-shaped pendulum element affixed to the bar and tunable so that the mass of the pendulum defines a first eigenfrequency of vibration of the damper corresponding to the fundamental and the moment of inertia about an axis perpendicular to the axis of the bar is tuned to a second eigenfrequency corresponding to the fundamental.

Abstract: A manufacturing process for high performance single mode channel optical guides of the LiNbO.sub.3 using five successive steps: photo-etched optical path definition, deposition of the dielectric layer, lift-off definition of the channels, proton exchange and thermal cycling. The method can be used to produce multi-function devices to be interfaced with optical fibers to obtain sensors, telecommunications devices and devices for processing wide-band microwave signals the proton exchange is affected in benzoic acid diluted with lithium benzoate and eliminates the time instability of the electro-optical structure due to the presence of an insulating layer above the optical guide.

Abstract: Detector of suspended cables specially suited for avionic applications formed mainly by a scanning system (S) provided with a noise generator (1) and scan concentrator (3); by a Lidar system (L) and an extractor system (E). The latter is composed of a background filter (7) and a chain extractor (8). This detector, if included in the on board instrumentation of light aircrafts and helicopters, is in condition of supplying the pilot with a warning signal if suspended cables are detected in the flight path during low altitude flights. The instrument gives the cable position and allows the selection of the right corrective move.The invention finds its most convenient application in the flight safety field while that of the avionic optical radars is the specific technical field of this device.