Thomson-csf

Cecile Joubert

Brigitte Loiseaux

Jean-Pierre Huignard

Jean-Claude Lehureau

Christophe Nicolas

Anne Delboulbe

Claude Puech

Erich Spitz

Pascal Joffre

Display device and flat television screen using this device

An illumination device comprises a light source coupled to a waveguide. the waveguide comprises a diffracting element capable of diffracting emergent light rays coming from the source, in a direction substantially perpendicular to the surface of the waveguide. A device of this kind is particularly well-suited to transmissive display screens of the liquid crystal display screen type. It can generate a highly collimated, polarized light.

Illumination device and application thereof to the illumination of a

Optical filtering device and application to a liquid crystal projector

The color display device includes at least a light source which emits at least two primary wavelengths and an array of holographic lenses (HL). Also included is a spatial light modulator (LCD) which includes one picture element (pixel) for each holographic lens with each pixel including one subpixel for each wavelength to be displayed. Each of the holographic lenses disperses the various wavelength and focuses each of them into one of the subpixels. The structure allows for a single lens structure for the various wavelengths.

Color display device for monovalve projectors

Color display device in which the area of a spherical lens equals the

A back projection device comprises an image generator (GI), an onward reflection mirror (MR) and at least one optical component (OM) capable of reflecting certain types of light beams almost entirely and reflecting certain other types of light beams almost entirely, said component being located in the proximity of a screen (E). The selection of optical behavior of the component (OM) may be done as a function of the polarization of the light beam, or else also as a function of its orientation with respect to said component (OM). Application: displays.

Compact back projection device having either a diffractive optical

This invention concerns chromatic light separators, and is particularly intended to reduce their dimensions. A chromatic separator in accordance with the invention contains at least two selective wave length mirrors. According to one characteristic of the invention, the two selective mirrors are nested holographic mirrors. The invention is particularly suitable for three-color rear-projection type picture projectors using liquid crystal screens.

Chromatic light separator and picture projector using a chromatic light

Video image projector with improve luminous efficiency

A color display device comprises a source of light simultaneously emitting several ranges of chromatic components and a spatial light modulator comprising several dots, each dot comprising at least one sub-pixel per range of chromatic component to be displayed. Between the light source and the spatial light modulator there are provided at least one chromatic separator angularly separating the light of the different chromatic range along different directions, a lens focusing the light of the different chromatic ranges at distinct points or along distinct lines contained in a determined plane, at least one spatial filter located along this determined plane and selectively filtering the light of the different chromatic ranges, and an array of lenses, each enabling the focusing of the light of each chromatic range substantially on a sub-pixel.

Color display device with intervening lens and spatial filter or with

Disclosed is a separator of polarizations comprising a Bragg grating gripped between two plates comprising input and output faces in the form of steps. The advantages of the device are that it is light and compact.

Growing community of inventors

Paris, France

Cecile Joubert