Thales

Sextant Avionique

Thales Avionics S.a.

Thomson-csf Sextant

Thomson-csf Sexant

Laurent Potin

Siegfried Rouzes

Bruno Barbier

Laurent Bignolles

Jo&euml;l Baudou

Jean-Pierre Gerbe

Ludovic Pennetier

The general field of the invention is that of systems for detecting the posture of a moving object. The system may include a fixed electro-optical device of known orientation comprising an emission source, an image sensor and image analysis means, and an optical assembly comprising an optical retroreflector arranged on the moving object. The optical retroreflector of the system is an optical sphere of variable index comprising a transparent hemisphere and a reflecting hemisphere. It comprises a meshing comprising at least three opaque wires, of small thickness and known geometrical arrangement. The image of the retroreflector lit by the source forms a reflection on the image sensor, said reflection comprising at least the two images of the shadow of one of the three wires. The image analysis means detect the orientation of the leak line given by said images, said orientation being representative of one of the parameters of the posture of the moving object.

Posture detection system with retroreflector comprising a wire-meshing

The general field of the invention is that of systems for detecting the posture of a mobile object in space. The system according to the invention comprises an electro-optical device comprising a light source, a photoreceptor and means of analysis, and a retro-reflecting cube corner disposed on the mobile object. The cube corner comprises a mask disposed on its entry face. The source emits a parallel or almost-parallel pencil beam. The electro-optical device comprises means for deviating, about a fixed point, the said pencil beam of light by an angle varying as a function of time. The photoreceptor is configured for receiving the pencil beam of light retro-reflected by the cube corner. The means of analysis are configured in such a manner as to determine, based on the signal coming from the photoreceptor, the position of a number of points representative of the borders of the mask and, using this positional information, the posture of the cube corner in space.

Optical system for posture detection comprising a scanning light source and a cube corner

The general field of the invention is that of systems for detecting the posture of a mobile object. The systems according to the invention comprise a fixed electro-optical device comprising an emission source and a photosensitive sensor. The optical corner cube is arranged on the mobile object. The entry face of the corner cube has a predetermined geometry, the light coming from the source and reflected back by the corner cube forming a luminous contour on the matrix sensor. The fixed electro-optical device comprises an optical element with a known shape and location, which is placed in the vicinity of the said source and is arranged so as to form a dark zone in the central part of the luminous contour. The detection system comprises analysis means determining the position and the orientation of the mobile object from knowledge of the vanishing points of the luminous contour and the position and shape of the dark zone.

Optical system for measurement of orientation and position comprising a point source, central mask, photosensitive matrix sensor and corner cube

The overall field of the invention is that of systems for detecting the posture of a moving object in space. The device according to the invention comprises: a fixed electrooptical device comprising a point emission source, a telecentric lens comprising a projection lens, a reception lens and a semireflective optical element and a photosensitive matrix-type sensor, the point emission source being arranged at the common focal point of the projection lens and of the reception lens by reflection or transmission through the semireflective optical element, and; an assembly comprising at least three corner cube retroreflectors which are arranged on the moving object. The main application of this device is the detection of the orientation of an aircraft pilot helmet.

Optical system for measuring the orientation of a helmet using corner cubes and a telecentric emission lens

The field of the invention is that of optical systems for detecting the posture of a mobile object in space. The system comprises an electro-optical fixed device of known orientation comprising a first point emission source, a telecentric emission/reception optic and a photosensitive matrix sensor. An assembly comprising an optical cubic wedge is disposed on the mobile object. The input face of the cubic wedge comprises a mask in the shape of a parallelogram, each side of the parallelogram comprising a geometric marking making it possible to identify it, the image of the mask projected on the photosensitive matrix sensor, by reflection on the faces of the cubic wedge, being the intersection of the projection of the mask and of the projection of its image inverted with respect to the centeR of the cubic wedge. Analysis of this image makes it possible to determine the orientation of the cubic wedge.

Optical system for measuring orientation with cubic wedge and mask

The general field of the invention is that of systems for the optical detection of the orientation and the position of a mobile object in space. The system comprises a fixed electro-optical device comprising a transmission point source, image analysis means and an optical cube corner disposed on the mobile object. The input surface of the cube corner comprises a polygonal-shaped mask, the sides of which comprise a geometric marking to identify them. The fixed electro-optical device comprises photosensitive means close to the point source and disposed in two different recording planes and recording two luminous shapes in perspective of the mask obtained by reflection on the surfaces of the cube corner. The image analysis means comprise means for determining the vanishing points of the two luminous shapes in the two recording planes, the knowledge of the four vanishing points enabling the determination of the position and orientation of the optical cube corner in relation to the fixed electro-optical device.

Optical system for measuring orientation and position without image formation with point source and mask

The general field of the invention is that of optical position/orientation devices for a helmet and more particularly those whose helmet comprises neither emitters, nor receivers but solely passive optical components, detection of which is ensured by fixed opto-electronic means outside the helmet. The optical component for the optical device for detecting position/orientation of a helmet according to the invention comprises a particular 'optical cube corner'. It comprises a prism in the form of a trirectangular trihedron, each of the three plane surfaces of the trihedron comprising a blade with plane and mutually parallel faces, the first face being coincident with the plane surface on which it rests, the interface between this first face and said surface comprising a semi-reflecting treatment.

Optical reflector having semi-reflective blades for a position detection device for a helmet, and helmet comprising such a device

An optical device for a system presenting collimated images through an off-axis spherical concave mirror. An image can be presented to a user with correction of eccentric distortion caused by the off-axis spherical concave mirror without altering the quality of the image. A diffractive mirror is set in the neighborhood of an intermediate image, and preferably a second intermediate image. The extent of the neighborhood is limited by image resolution and, in the neighborhood, the correction by the diffractive mirror does not alter the resolution. The diffractive mirror may include a hologram which may be digital or made of a photosensitive material. A hologram substrate is preferably not planar to operate partly upon the correction, the residual correction being carried out by the hologram. Such a device may find application to an aircraft pilot's visor.

Optical device for helmet visor comprising a diffractive mirror

Visors for helmets are generally of spherical shape and of constant thickness, and articulated to the side walls of a helmet at the level of the forehead, about an axis of articulation passing through the center of their sphere. Thus shaped and mounted, they are seen off axis by a helmet wearer leading to optical distortions for him caused by diffraction effects on their internal and external faces. Visors with shapes modified to minimize the optical distortions perceived by a helmet wearer are proposed here. A first type of modification consists of a relative pivoting, in the vertical plane, of one of the faces of the visor with respect to the other and of a slight reduction in the ratio of the radius of curvature of the outer face of the visor to that of the inner face of the visor compared to the usual concentric bispherical visor. A second type of modification consists of adopting one or two aspherical surfaces of particular shape. A third type of modification consists of using a holographic diffraction mask fixed to one of the faces of the visor.

Visor for a helmet

The invention relates to an optical device for a system for presenting collimated images including an off-axis spherical mirror. The device has an additional aspherical mirror whose surface forms, in the plane of symmetry of the unfolded optical system, a curve whose radius of curvature is variable. The surface provides for correction of the image of a pupil of an eye given by the spherical mirror and the pupil image is rectified on the optical axis. The surface may be a paraboloid, an ellipsoid and it may exhibit symmetry of revolution.

Optical device for helmet visor comprising aspheric mirror

An optronic device fitted with a focusing mirror for projection on a visor. A plane mirror is placed between the last active component of the optronic device and the visor. The mirror is attached to a reinforcement of the device by an elastomeric seal that presses the mirror against screws screwed into the reinforcement. The ends of each pair of screws form axes about which it is possible to pivot the mirror. An identical action on each of the screws makes it possible to move the mirror in translation. Adjusting the mirror makes it possible to alter the position of the visor seen by an optical module of the optronic device, and therefore to focus the image on the visor so that it is as sharp as possible. This corrects placement errors of the visor and its curvature defects.

Optronic device equipped with a focusing mirror for visor display

An optical device for a system presenting collimated images using a spherical mirror. The optical device makes it possible to present the user with an image corrected of off-centring distortion of a second kind due to an off-axis spherical mirror. In order to do this the optical device includes a tubular mirror whose optical characteristics ensure a high-quality image and correction of the off-centering distortion. The tubular mirror has a surface generated by the translation of a plane curve (a circular arc) along another plane curve (also a circular arc). The optical device is especially applicable to helmet sights for an aircraft pilot.

Optical device for pilot's visor comprising a tubular mirror

A helmet with night vision system. The system includes an image generator, an optical mixing system for mixing the light rays output by the night vision system and the light rays output by the image generator and a fixed optical system downstream of the optical mixing system. All of the night vision system and the optical mixing system can be removed and a substitute optical system can be inserted for daytime vision. The substitute optical system has the same optical characteristics as the optical mixing system, but has a transmission coefficient higher than that of the optical mixing system. The substitute system is optimized for day vision while the mixing system is optimized for night vision. The helmet may be used for pilots of combat helicopters or airplanes.

Helmet with night vision system and optic capable of being substituted for day vision

A display device for a helmet-mounted visual system including an intensified image-taking device and a visor to combine the intensified images and an ambient scene before the pilot's eyes. The display device also includes an optical prism whose optical aberrations (image distortions, astigmatism) are capable of compensating for the aberrations created by the visor of the helmet, on the images given to the pilot.

Display device for helmet-mounted display

An optical device for a system for the presentation of collimated images by a non-plane mirror, which makes it possible to present a user with an image corrected of distortion due to a non-plane mirror and exhibiting good resolution. To do this, the device includes a Mangin type mirror whose optical characteristics ensure good image quality of correction of off-centering distortion and good image sharpness. The Mangin type mirror has a reflecting surface and a layer of refracting material defining a refracting surface. One surface may be spherical, and the other aspherical. The surfaces may also be aspherical. One aspherical surface may be a paraboloid, an ellipsoid, or a torus. The refracting material can exhibit an optical index varying according to the position on the surface of the mirror. The device may be applied in particular to a system for the presentation of collimated images by a spherical mirror inclined with respect to the direction from which it is observed. The Mangin type mirror then corrects the off-centering distortion of the second kind due to this off-axis spherical mirror. The device may be applied in particular to helmet viewfinders for an aircraft pilot.

Growing community of inventors

Bordeaux, France

Laurent Potin