Abstract: An illuminating device is described comprising an optical source emitting an unpolarized light beam, a polarizing beam splitter comprising a grid polarizer situated between the faces of two prisms. The light beam penetrates into the first prism through a face and reaches the polarizing beam splitter that transmits the light having a first polarization direction to the face that reflects it toward an exit face. In addition, the splitter reflects the light having a second polarization direction to the face that reflects it toward an exit face.

Abstract: Device comprising: a rear panel comprising a network of backlighting elements, a front panel comprising a network of optical valves which are each capable of modulating the brightness of a single primary colour. By the modulation of chrominance which is added to the modulation of luminance for the backlighting elements of the rear panel, the device according to the invention makes it possible to display the images with even more contrast and better quality. A specific control mode makes it possible to avoid the colour “interferences”.

Abstract: A method for optimizing operation which is applicable to a multiprocessor integrated circuit chip. Each processor runs with a variable parameter, for example its clock frequency, and the optimization includes determination, in real time, of a characteristic data value associated with the processor (temperature, consumption, latency), transfer of the characteristic data to the other processors, calculation by each processor of various values of an optimization function depending on the characteristic data value of the block, on the characteristic data values of the other blocks, and on the variable parameter, the function being calculated for the current value of this parameter and for other possible values, selection, from among the various parameter values, of that which yields the best value for the optimization function, and application of this variable parameter to the processor for the remainder of the execution of the task.

Abstract: A Fresnel lens comprises at least one first prism and one second prism. Each prism has a first side and a second side which forms with a main axis an angle greater than that formed by the first side and the main axis. Conventionally, the second side of the first prism collimates the light received from a light source in line with the main axis. In order to improve the optical effectiveness, the second side of the second prism transmits the light received from the source in a first direction slightly different from the main axis.

Abstract: The invention relates to informative eyeglasses (500) comprising:—an optical guide (514) forming an eyeglass lens (500) and exhibiting an injection section (504) and an extraction section (508),—a catadioptric collimator (150) comprising:—a refractive entrance surface (202), a first reflecting surface (204), a second reflecting surface (206) and a refractive exit surface (208), each surface (202, 204, 206, 208) constituting a surface of revolution with the same axis of revolution, said axis of revolution constituting the optical axis (102) of the collimator (150),—an illumination source (104) generating an incident light beam (108) illuminating the refractive entrance surface (202), and the axis of which is shifted with respect to said optical axis (102) and which is substantially in the focal plane of said catadioptric collimator (150).

Abstract: A projection module intended to project an image on a screen defining a specified projection plane is disclosed. The module includes an objective, for emitting an imaging beam; a curved mirror; and at least two deflection surfaces for deflecting the imaging beam, the deflection surfaces being placed in the path of the imaging beam between the objective and the curved mirror.

Abstract: Optical system for a projector, comprising: at least a first polarizing beam splitter for splitting a source illumination beam into a first illumination beam linearly polarized along a first direction and a second illumination beam polarized perpendicular to the first direction; at least one color wheel intersecting the polarized illumination beams in two different regions and producing a first color beam linearly polarized along the first direction and a perpendicularly polarized second color beam; and two imagers illuminated by the first and second polarized color beams respectively.

Abstract: A Fresnel lens comprises at least one first prism and one second prism. Each prism has a first side and a second side which forms with a main axis an angle greater than that formed by the first side and the main axis. Conventionally, the second side of the first prism collimates the light received from a light source in line with the main axis. In order to improve the optical effectiveness, the second side of the second prism transmits the light received from the source in a first direction slightly different from the main axis.

Abstract: An optical plate, in particular in a screen for projection display device, comprises, on a first side, optical elements designed to bend rays received from a light source into a beam of rays in a first direction in a plane containing a main axis. The second side is produced in such a way as to bend the beam in a second direction that is different from the first direction, preferably in line with the main axis.

Abstract: The invention relates to an illumination system for combining two light beams. A prism bounded by two entrance faces that form a dihedron. An integrator is coupled to an exit face (20.3) of the prism. Each beam penetrates the prism via one of the entrance faces and is reflected by internal reflection on the other entrance face toward the exit face. These beams are substantially focused onto the entrance face of the integrator in such a way that the latter delivers an almost uniform exit beam. Applications: Projection and backprojection apparatus.

Abstract: The invention relates to a projection objective comprising at least one lens and intended to transmit a divergent light beam onto a flat screen. A hyperbolically shaped mirror is oriented so as to receive, on its convex face, the light emanating from the lens. The invention also relates to a corresponding projection apparatus.

Abstract: The invention relates to a projection system comprising an image source and an objective lens for producing an imaging beam and producing a first image there behind, wherein the first image is off-axis with respect to the imaging beam optical axis. The inventive system comprises a concave mirror which is arranged after the first image on the imaging beam path and produces a second image on a projection plane from the first image.

Abstract: Optical system for a projector, comprising: at least a first polarizing beam splitter for splitting a source illumination beam into a first illumination beam linearly polarized along a first direction and a second illumination beam polarized perpendicular to the first direction; at least one colour wheel intersecting the polarized illumination beams in two different regions and producing a first colour beam linearly polarized along the first direction and a perpendicularly polarized second colour beam; and two imagers illuminated by the first and second polarized colour beams respectively.

Abstract: The invention relates to a Fresnel lens. Each refractive structure of the lens is bounded by two surfaces, the second surface making a second angle with the normal to the plane of incidence. At least two zones of refractive structures are provided in which the second angle is equal to the entrance angle of a beam. Each first surface refracts the light along a direction parallel or not parallel to the axis of the lens depending on the zone. The invention also relates to a system comprising a folding mirror and a Fresnel lens, in which system the second angle is equal to the entrance angle of a parasitic ray obtained by reflection on the Fresnel lens and then on the mirror. The invention also relates to a corresponding back projection screen and a corresponding back projection unit.

Abstract: An image-display panel is described. The panel includes a one-dimensional or two-dimensional matrix of organic electroluminescent cells deposited on a substrate and grouped together in rows or columns. Light extraction elements are deposited on each row or column of cells to form an extraction layer.

Abstract: The invention relates to an illumination system intended to illuminate an imager, which comprises a plurality of illumination sources generating source beams having two separate polarizations. To optimize the effectiveness of the source beams, the source beams illuminate a grid polarizer, one polarization passes through the polarizing surface of the polarizer, before being reflected by a mirror and passing again through the polarizing surface; the second polarization is reflected by the polarizing surface, the two polarizations thus being spatially separate; next, half-wavelength phase shift means phase-shift only one of the two polarizations. The invention also relates to a projector comprising the illumination system, the imager and a projection objective.

Abstract: The invention concerns a display apparatus with an imager illuminated by an illumination system and with an imaging system projecting an image on a viewing screen, wherein the brightness of the image on the imager has a variation over a given direction, and wherein the illumination system has light controlling elements for controlling the light distribution over the given direction.

Abstract: The invention relates to a projection module intended to project an image on a screen defining a specified projection plane. The module comprises: an objective, which itself comprises means for emitting an imaging beam; a curved mirror; and at least two deflection surfaces for deflecting the imaging beam, these surfaces being placed in the path of the imaging beam between the objective and the curved mirror. The invention also relates to an optical motor and to a corresponding projection system.

Abstract: The invention relates to a projection objective comprising at least one lens and intended to transmit a divergent light beam onto a flat screen. A hyperbolically shaped mirror is oriented so as to receive, on its convex face, the light emanating from the lens. The invention also relates to a corresponding projection apparatus.

Abstract: The invention relates to a Fresnel lens. Each refractive structure of the lens is bounded by two surfaces, the second surface making a second angle with the normal to the plane of incidence. At least two zones of refractive structures are provided in which the second angle is equal to the entrance angle of a beam. Each first surface refracts the light along a direction parallel or not parallel to the axis of the lens depending on the zone. The invention also relates to a system comprising a folding mirror and a Fresnel lens, in which system the second angle is equal to the entrance angle of a parasitic ray obtained by reflection on the Fresnel lens and then on the mirror. The invention also relates to a corresponding back projection screen and a corresponding back projection unit.